Embodiment
[first embodiment]
Below with reference to Fig. 1, Fig. 2, Fig. 3 and Fig. 4 the first embodiment of the present invention is described.
This embodiment is the embodiment of glasses display (corresponding to the image-display units in the claim).
The structure of this glasses display at first, is described.
As shown in Figure 1, this glasses display comprises image displayoptical system 1,image input block 2,cable 3 etc.This image displayoptical unit 1 andimage input block 2 are supported by thesupport member 4 that is similar to frame, and are worn on observer's head last (thissupport member 4 comprisestemple 4a,support ring 4b, bridgeware 4c etc.).
This image displayoptical system 1 has the outward appearance and its periphery that are similar to eyeglass to be supported by thissupport ring 4b.
Thisimage input block 2 is supported by temple 4a.Image input block 2 is supplied with picture signal and power supply viacable 3 from external device (ED).
When glasses display was put on, image displayoptical system 1 was arranged on the front (below, suppose right eye and be referred to as " observation eyes ") of observer's eyes.Below will be according to the observation the glasses display put on of the location expression observed person of person and these observation eyes.
As shown in Figure 2, thisimage input block 2 has: based on the liquid crystal display cells 21 (corresponding to the image-displaying member in the claim) of the picture signal display image of supplying with viacable 3; With near theobject lens 22 of its focus this liquidcrystal display cells 21.
Thisimage input block 2 emission images transmission luminous flux L1 (visible light), this luminous flux shine the right end portion on surface of observer's one side of this image displayoptical system 1 fromobject lens 22.
This image displayoptical system 1 comprisesplanar substrates 13,planar substrates 11 andplanar substrates 12, and its order from observer's one side is overlapping in the mode of tight contact.
Planar substrates 13,planar substrates 11 andplanar substrates 12, each is by having the material of visible light transmissive character (for example optical glass) manufacturing at least.
Wherein, thisplanar substrates 11 is the plane-parallel plates that cause the internal reflection of image transmission luminous flux L1 repeatedly, and this luminous flux enters on the outer surface 11-1 and the surperficial 11-2 (corresponding to the planar substrates the claim) of observer's one side fromimage input block 2.
Thisplanar substrates 12 is arranged on the outside ofplanar substrates 11, works the diopter corrective action of observing eyes.Thisplanar substrates 12 is that its outer surface 12-1 is that plane surface two observer's side surface 12-2 are lens of curved surface.
Thisplanar substrates 13 that is arranged on observer's side of thisplanar substrates 11 also works the diopter corrective action of observing eyes.Thisplanar substrates 13 is that its outer surface 13-1 is plane and the surperficial 13-2 of observer's one side is the lens of curved surface.
In addition, at surperficial 13-2, the zone that this image transmission luminous flux L1 at first passes through is the plane, does not have the optical power that is used for image transmission luminous flux L1.
And in theseplanar substrates 11 inboards, image transmission luminous flux L1 is incident zone thereon at first, is formed with guidingcatoptron 11a, and its angle with this image transmission luminous flux L1 changes over the angle that it can be reflected by inside surface in thisplanar substrates 11.
And, in thisplanar substrates 11, be provided with half-reflectingmirror 11b (corresponding to the compositor in the claim), this image transmission luminous flux that it has been reflected by inside surface along direction reflection of this pupil in zone towards the pupil of these observation eyes.
Without this half-reflectingmirror 11b, also can be with having along the HOE (it represents holographic optical elements (HOE)) of the character of the light of the predetermined diffraction conditions of predetermined direction polarized matching.And this compositor can have optical function.
Here, betweenplanar substrates 12 andplanar substrates 11,substitute film 12a and be arranged to that both closely contact with this.And, betweenplanar substrates 13 andplanar substrates 11, substitute film 13a and be arranged to that both closely contact with this (thisalternative film 12a, 13a are corresponding to the optical function unit in the claim).
Substitute film 12a, 13a, each has reflection with about 60 ° of incident angle incidents visible light thereon, and transmission is with the character of about 0 ° incident angle incident visible light thereon.
Below, the situation that is provided with in detail of the respective surfaces of this image displayoptical system 1 will be described according to the situation of this image transmission luminous flux L1.
As shown in Figure 2, because enter thisplanar substrates 13 viaobject lens 22 with about 0 ° incident angle from the image transmission luminous flux L1 (the image transmission luminous flux of observing central angle only is shown) of the display screen emission of the liquidcrystal display cells 21 of thisimage input block 2, this image transmission luminous flux L1 is incident on theplanar substrates 11 by substituting film 13a.
The image transmission luminous flux L1 that entersplanar substrates 11 is incident on guidingcatoptron 11a with predetermined incident angle and by its reflection.The image transmission luminous flux L1 that is reflected is incident on this alternative film 13a with about 60 ° of incident angle θ, therefore is reflected on alternative film 13a to guide towards alternative film 12a.This also is incident on incident angle θ by image transmission luminous flux L1 and substitutes on thefilm 12a, therefore also is reflected on thisalternative film 12a.
Therefore, image transmission luminous flux L1 propagates towards the place away from thisimage input block 2 more along the direction in observer left side, simultaneously interreflection alternately onalternative film 12a, 13a.
Thereafter, this image transmission luminous flux L1 is incident on half-reflectingmirror 11b upward with the direction reflection along the pupil of observing eyes.
The image that is reflected transmission luminous flux L1 with about 0 ° incident angle be incident on substitute that film 13a goes up and therefore by this alternative film 13a to incide viaplanar substrates 13 on the pupil of observing eyes.
Exterior light flux L2 from outside visual field (far point) is incident on thealternative film 12a with about 0 ° incident angle viaplanar substrates 12, and therefore substitutes on the film 13a to be incident on about 0 ° incident angle viaplanar substrates 11 by this alternative film 12a.This exterior light flux L2 by this alternative film 13a to be incident on viaplanar substrates 13 on the pupil of observing eyes.
Here, the shape of the surperficial 13-2 of observer's one side of the shape of the outer surface 12-1 ofplanar substrates 12 andplanar substrates 13 is arranged to proofread and correct so that observe the diopter of eyes.
In addition, the combination of proofreading and correct the shape of shape by the surperficial 12-1 in the light path that is arranged on exterior light flux L2 and surperficial 13-2 for the diopter of the observation eyes of outside visual field realizes.The shape of proofreading and correct by the surperficial 13-2 in the light path that is arranged on image transmission luminous flux L1 for the diopter of image observation eyes realizes.In order to realize proofreading and correct, regulate simultaneously along the position of optical axisdirection object lens 22 with along the position of optical axis direction liquidcrystal display cells 21 for the diopter of image observation eyes.
In the above in the glasses display of Miao Shuing, be arranged on element the light path from liquidcrystal display cells 21 to pupil corresponding to the combiner optical systems in the claim.
Below, will describe in detail andsubstitute film 12a, 13a.
(1) about the inner full-reflection in theplanar substrates 11
Generally speaking, surpass critical angle θ when incident angle by expression (1) expressionCThe time, inner full-reflection takes place in theplanar substrates 11 in being arranged at medium,
θC=arc sin[nm/ ng] ... (1) wherein
nmBe the refractive index of medium, and ngIt is the refractive index of planar substrates 11.This expression formula (1) shows, in order to be applicable to θCExistence, must make nm<ng
Therefore, directly will make the refractive index of medium too high by the lip-deepplanar substrates 12,13 atplanar substrates 11, it does not allow θCExistence, make that the internal reflection function is destroyed.
On the other hand, if the gap is arranged on the surface ofplanar substrates 11, the low-refraction (n of medium (air)m=1.0) making it can realize the internal reflection function, is general optical glass BK7 (n because work as the material ofplanar substrates 11g=1.56) time, expression formula (1) provides about 40 ° critical angle θC
In addition, when utilizing the clearance, the incident angle characteristic of the reflectance ofplanar substrates 11 is shown in Fig. 3.
(2) about the insulativity optical multilayer film
In the theory of insulativity optical multilayer film, find following relation.
The membrane structure (being described below) of the symmetrical film of being made by the insulativity optical multilayer film will be discussed below, and this insulativity optical multilayer film is clipped between two planar substrates being made by optical glass.Here, symmetrical film is meant such membrane structure, and various layers are that the center overlaps symmetrically in this structure.Layer group as a unit is placed in the bracket, and its structure is shown in this bracket (this layer group be applied to describe below).
Planar substrates/(0.125L0.25H0.125L)k/ planar substrates, or
Planar substrates/(0.125H0.25L0.125H)k/ planar substrates
In each layer group, H represents high refractive index layer, L represents low-index layer, the upper right mark k of each layer group represents the lamination number in each layer group, the thickness of the optical layers of the centre wavelength of the light of the numeral of writing before each layer group on being used to be incident on every layer on every layer (it is applied to describe below).
Knew already, the film of symmetry can be treated to the single film (equivalent film) of the equivalence with virtual refractive index, and the theory of the equivalent refractive index of symmetrical film and this film (equivalent refractive index) is described in detail in " the Thin-Film opticalFilters 3 that people such as HA.Macleod writesRd" in the literary composition, so its detailed description here is removed Edition.
In this membrane structure, if being used for the equivalent refractive index of the equivalent film of vertical incident light is arranged to identical with the refractive index ofplanar substrates 11, this equivalence film does not cause the boundary reflection of vertical incident light, therefore for 100% transmittance that has of this light, but cause boundary reflection, therefore increase this reflection of light with the incident light of big incident angle.Its reason is because dielectric apparent refractive index N changes according to the propagation angle θ of the light in the dielectric usually.
N=ncos θ (s-polarized light)
N=n/cos θ (p-polarized light)
Notice that n is this dielectric refractive index.In addition, according to the increase of incident angle, for the s-polarized light, the recruitment of reflectance is obvious especially.
(3) about substitutingfilm 12a, the structure of 13a
The see-through property (equaling external visibility) that does not damage the internal reflection of the planar substrates of mentioning 11 andplanar substrates 11 in (1) is foralternative film 12a, and 13a is essential.That is to say that they need have the character of reflected image transmission luminous flux L1 and the character of transmission exterior light flux L2.
Therefore,substitute film 12a, 13a is configured to so that have with high reflectance (preferred total reflection) reflection with critical angle or with the character greater than the angle incident light thereon of critical angle, this critical angle is determined by the difference of the refractive index between thisplanar substrates 11 and the air.
In this embodiment,substitute film 12a, 13a character be arranged to " reflection with about 60 ° of incident angle incidents thereon visible light and transmission with the character of about 0 ° of incident angle incident visible light thereon ".This character can obtain by the insulativity optical multilayer film of describing in (2).
Therefore, in this embodiment, the insulativity optical multilayer film is used asalternative film 12a, 13a.
The method that structure substitutesfilm 12a, 13a is as follows.
The structure (structure of elementary layer group, overlapping number, every layer thickness, every layer refractive index, every layer material etc.) ofalternative film 12a, 13a is optimized according to the incident angle that presents highly reflective (being 60 ° here) of light.Optimize the refractive index ofplanar substrates 11 simultaneously.The basic structure that substitutesfilm 12a, 13a is the symmetrical film of describing in (2).
Yet promptly the theory described in (2) of box lunch is simplified application, and the refractive index of separating and being present in membraneous material that obtains is coupling mutually also, therefore, and measure all or part of below the employing in structure.
First measure is to insert several layers (matching layer) onplanar substrates 11 1 sides, its objective is the coupling that realizes withplanar substrates 11
Second measure be in the absorbing material index distribution and when optimizing the spectral characteristic/angular characteristics to the reflection/transmission of this material finely tune.
The 3rd measure is to destroy symmetry (allowing asymmetric) as required.
The 4th measure is the automatic Synthesis of utilizing optimizing structure of bed thickness and membrane structure by computing machine.
The 5th measure is the structure film so that only have desirable characteristic for s-polarized light (because the insulativity optical multilayer film has the character that increases the amount of its reflectance according to the increase of incident angle, this character is obvious especially for the s-polarized light).
The 6th measure is this film of structure so that only have desirable characteristic for predetermined wavelength.
In addition, the 5th measure is effective when the light source of liquid crystal display cells shown in Figure 2 21 is the s-polarized light source.If its polarization direction rotates by phase-plate etc., the 5th measure also can make it effective under p-polarized light source situation.The restriction polarization direction is favourable, because therefore the degree of freedom of structure strengthens.
When the light emitted of liquid crystal display cells shown in Figure 2 21 has light time of certain wavelength, the 6th measure is effective.Wavelength-limited is favourable, because therefore the degree of freedom of structure strengthens.
The effect of glasses display will be described below.
In this glasses display,substitute film 12a, 13a and be formed on the outside and observer's one side ofplanar substrates 11.
The character that substitutesfilm 12a, 13a be arranged in case their reflections with about 60 ° incident angle incident thereon visible light and transmission with about 0 ° incident angle incident visible light thereon.
Theplanar substrates 11 that is clipped in the middle by thesealternative film 12a, 13a can cause image transmission luminous flux L1 internal reflection and can transmission from the exterior light flux L2 of outside visual field (far point).
Therefore, even if paste theplanar substrates 12,13 that has same refractive index withplanar substrates 11, do not damage the internal reflection function and the see-through property ofplanar substrates 11 yet.
As a result, utilize the straightforward procedure of only pasting thissubstrate 12,13, this glasses display can have diopter and proofread and correct.
In addition, the light absorbing material that is used forplanar substrates 12,13 can make glasses display have the function of sunglasses.Be essential and do not need under the situation of diopter correction that in the function of having only sunglasses thisplanar substrates 12,13 can be the planar row flat board of light absorption.
(other)
In this embodiment, image transmission luminous flux L1 is a visible light, and the character ofplanar substrates 11 andalternative film 12a, 13a is arranged to the character of inside surface reflect visible light, but it should be noted that, when the light source of liquidcrystal display cells 21 had emission spectrum, this character can be arranged to, and it had the light of peak wavelength at least so that inside surface reflects.
And, in the glasses display of this embodiment, diopter is proofreaied and correct by two planar substrates (planar substrates 11,12) and two alternative films (substitutingfilm 12a, 13a) and is realized, but diopter is proofreaied and correct and can be realized by a planar substrates and an alternative film.
Also have, in this embodiment, the insulativity optical multilayer film still can be used HOE as substitutingfilm 12a, 13a.Utilizealternative film 12a, the 13a of insulativity optical multilayer film, the example that will be described later of the details of structure in describe,, the method for making HOE will be described below here.
Fig. 4 illustrates the optical system that is used to make HOE.This optical system manufacturing is with the HOE of high reflectance reflection with incident angle θ incident image transmission luminous flux L1 thereon.
Be divided into two light beams from the laser beam with wavelength X ofLASER Light Source 31 emissions by minute beam tube 32.The laser beam of these two separation is expanded respectively by twooptical beam expanders 33, and is incident on theholographic photochromics 35 via twoauxiliary prisms 34 respectively thereafter.Therefore photochromics 35 is exposed.Here, the incident angle of laser beam on holographic material is set to θ.Thisphotochromics 35 is developed out to finish HOE.
This HOE that finishes has such character: cause the diffraction/reflection of the luminous flux with predetermined wavelength lambda thereon of θ incident at a predetermined angle, and complete transmission is with about 0 ° incident angle incident light thereon.
In addition, substituting the incident angle thatfilm 12a, 13a show the pairing light of reflectivity properties is different with wavelength, and therefore when the angle θ of laser beam and wavelength changed as required, thisphotochromics 35 was by multiexposure, multiple exposure.
And, utilize resin-based materials (resin sheet) can low-costly make and have large-area HOE as photochromics 35.And, be resin sheet as this HOE really, by pasting this HOE this HOE is closely contacted with theplanar substrates 11 of this glasses display, have very high practical value according to reducing cost and producing this HOE in batches.
Perhaps, the multilayer optical film of being made by metallic film, semiconductive thin film etc. can be as thealternative film 12a of this embodiment, each of 13a.But the insulativity optical multilayer film is more preferably, because it absorbs less light than this multilayer optical film.
Preferably, above-described optical function unit (insulativity optical multilayer film, HOE and other multilayer optical films) optionally is used asalternative film 12a, 13a according to specification and the cost that glasses show.
First example
Thealternative film 12a that is made by the insulativity optical multilayer film, first example of 13a will be described below.
When the light source of liquidcrystal display cells 21 was polarized light source, this example was an effective example.The basic structure of this example is as follows, for example
Planar substrates/(0.125L0.25H0.125L)k/ planar substrates
The refractive index of this planar substrates is 1.74, and the rate that is provided with of high refractive index layer H is 2.20, and the refractive index of low-index layer L is 1.48.
The N-LAF35 that is made by SCHOTT is used as planar substrates, TiO2, Ta2O5And Nb2O5One of them is used for forming high refractive index layer H under the film deposition conditions of regulating, and SiO2Be used to form low-index layer L.
In addition, the insulativity optical multilayer film with this basic structure is called " short wavelength's transmitting filter " usually.It has the characteristic that shows high transmittance for the short light of its wavelength ratio predetermined wavelength, and it shows high reflectance for the long light of its wavelength ratio predetermined wavelength.
The another kind of characteristic of general insulativity optical multilayer film is, when light obliquely incident thereon the time its spectral characteristic move to short wavelength's one side according to incident angle.
By making up this two specific character.Vertically the transmission wave band of incident light becomes in advance with whole visible spectrum (400~700 nanometer) and is complementary, and basic structure is optimized to the critical angle θ that convenient incident angle reachesplanar substrates 11CIn the time of on every side, the long wavelength side reflected waveband mates whole visible spectrum (400~700 nanometer).
Planar substrates/(0.125L0.28H0.15L) (0.125L0.25H0.125L)4(0.15L0.28H0.125L)/planar substrates
The refractive index of this planar substrates is 1.56, and the refractive index of high refractive index layer H is 2.30, and the refractive index of low-index layer L is 1.48, and central wavelength lambda is 850 nanometers.
The N-BAK4 that is made by SCHOTT is used as planar substrates, and high refractive index layer H is by TiO2, Ta2O5And Nb2O5One of them forms under the film deposition conditions of regulating.
In this example, Fig. 5, Fig. 6 and Fig. 7 illustrate respectively for the angular characteristics of vertical reflection of incident light ratio, the wavelength characteristic of reflectance, and for the wavelength characteristic of 60 ° of reflection of incident light ratios.In the accompanying drawing that is described below, Rs is the characteristic of s-polarized light, and Rp is the characteristic of p-polarized light, and Ra is the average characteristics of s-polarized light and p-polarized light.
As shown in Figure 5, when limiting the characteristic of s-polarized light, the angular characteristics of the reflectance of this example is the angular characteristics of the reflectance of matched glass substrate (see figure 3) well.And as shown in Figure 6, this example has high transmittance for the visible light of vertical incident.Also have, as shown in Figure 7, this example of incident light for 60 ° in whole visible light basically has 100% reflectance basically.
In this example, for example, matching layer is used for reducing the fluctuation of transmission wave band (wavelength coverage that reflectance is low).
Second example
Thealternative film 12a that is made by the insulativity optical multilayer film, second example of 13a will be described below.
When the light source of liquidcrystal display cells 21 was polarized light source, this example was an effective example.The basic structure of this example is as follows, for example
Planar substrates/(0.125H0.25L0.125H)k/ planar substrates
In addition, this structure is called " long-wave band transmitting filter " usually.It has the characteristic of high transmittance of its wavelength being longer than the light of predetermined wavelength, and shows as the characteristic of high reflectance for the light that its wavelength is shorter than this predetermined wavelength.
As the result who optimizes, this example has following structure.
Planar substrates (0.3H0.27L0.14H) (0.1547H0.2684L0.1547H)3(0.14H0.27L0.3H)/planar substrates
The refractive index of this planar substrates is 1.56, and the refractive index of high refractive index layer H is 2.00, and the refractive index of low-index layer L is 1.48, and centre frequency λ is 750 nanometers.
ZrO2, HfO2, Sc2O3, Pr2O6, and Y2O3One of them is used for forming high refractive index layer H under the film deposition conditions of regulating.Be used for planar substrates and low-index layer L with identical materials in the previously described example.
In this example, Fig. 8, Fig. 9 and Figure 10 illustrate for the angular characteristics of vertical reflection of incident light ratio and the wavelength characteristic of reflectance, and for the wavelength characteristic of 60 ° of reflection of incident light ratios.
As Fig. 8, Fig. 9 and shown in Figure 10, provide good characteristic for this example of s-polarized light, the characteristic of itself and first example is same basically.
In this example, the long-wave band transmitting filter is as basic structure.But according to the theory described in first embodiment (2), the short-wave band transmitting filter is suitable, but according to the research that is present in the refractive index in the membraneous material, this this basic structure of long-wave band transmitting filter of utilizing often provides design proposal.
The 3rd example
Thealternative film 12a that is made by the insulativity optical multilayer film, the 3rd example of 13a are described below.
This example is not effective example when the light source of liquidcrystal display cells 21 is not polarized light source.As the result who optimizes, this example has following structure
Planar substrates/(0.25H0.125L) (0.125L0.25H0.125L)4(0.125L0.25H)/planar substrates
The refractive index of this planar substrates is 1.75, and the refractive index of high refractive index layer H is 2.30, and the refractive index of low-index layer L is 1.48, and centre frequency λ is 1150 nanometers.
The N-LAF4 that SCHOTT makes is as planar substrates.High refractive index layer H TiO2, Ta2O5, and Nb2O5One of them forms under the film deposition conditions of regulating, and SiO2Be deposited to form low-index layer L.
Figure 11, Figure 12 and Figure 13 illustrate the angular characteristics for vertical reflection of incident light ratio, the wavelength characteristic of reflectance, and for the wavelength characteristic of 60 ° of reflection of incident light ratios.
As Figure 11, Figure 12 and shown in Figure 13, can obtain superperformance for p-polarized light and s-polarized light according to this embodiment.
The structure of this example is molded as following symmetrical structure.
Planar substrates/(matching layer group I)K1(symmetrical layers group)K2(matching layer group II)K3/ planar substrates
Each layer group made with overlapping repeatedly low-index layer L high refractive index layer H (LHL or HLH), and is arranged to have the reflectance of increase for 60 ° of incident lights.This central core group helps to reflect vertical incident light, and therefore, in order to reduce this reflection, every layer bed thickness is regulated by optimization in matching layer group I, II.
In structure, lamination number k1, the k2 of each of this model layer group, k3 increase/minimizing, and every layer bed thickness is regulated according to the refractive index of the incident angle of light and this planar substrates in matching layer group I, II.
With the relation of a planar substrates and the situation different with the relation of another planar substrates under (for example at two planar substrates under refractive index difference or adhered layer are arranged on situation between one of this example and planar substrates), the lamination number of matching layer group I, II and every layer bed thickness can be regulated separately.
And current, the method for the structure by the computer optimization bed thickness and the automatic Synthesis of membrane structure also is widely used.When utilizing this method, the scheme that relates to of acquisition departs from above-mentioned basic structure sometimes a little.But.This can be considered to have the basic structure (basic structure of modification) of its adjusted component.
The 4th example
Thealternative film 12a that is made by the insulativity optical multilayer film, the 4th example of 13a are described below.
This example is effective example when the light source of liquidcrystal display cells 21 is polarized light source.And this example is the example that the method with this membrane structure of computing machine automatic Synthesis is applied thereon.The basic structure of this example is shown in Figure 14.
As shown in figure 14, total number of plies is 19, and the refractive index of planar substrates is 1.56, and the refractive index of high refractive index layer H is 2.20, and the refractive index of low-index layer L is 1.46, and central wavelength lambda is 510 nanometers.
The N-BAK4 that SCHOTT makes is used to do planar substrates, and utilizes and the same high refractive index layer H of first example.SiO2Be used under the film deposition conditions of regulating, forming low-index layer L.
Figure 15, Figure 16 and Figure 17 are illustrated in this example the angular characteristics for vertical reflection of incident light ratio, the wavelength characteristic of reflectance, and for the wavelength characteristic of 60 ° of reflection of incident light ratios.
As Figure 15, Figure 16 and shown in Figure 17,, can obtain good characteristic according to this example.Particularly, as shown in figure 16, improve transmittance widely for vertical incident light.
The 5th example
Thealternative film 12a that is made by the insulativity optical multilayer film, the 5th example of 13a are described below.
This example is not effective example when the light source of liquidcrystal display cells 21 is not polarized light source.And this example is the example that the method with this membrane structure of computing machine automatic Synthesis is applied thereon.The basic structure of this example is shown in Figure 18.
As shown in figure 18, total number of plies is 40, and the refractive index of planar substrates is 1.56, and the refractive index of high refractive index layer H is 2.20, and the refractive index of low-index layer L is 1.3845, and central wavelength lambda is 510 nanometers.
The N-BAK4 that SCHOTT makes is used to do planar substrates, and utilizes and the same high refractive index layer H of first example, and MgF2And AlF2One of them is used for forming low-index layer L.
Figure 19, Figure 20 and Figure 21 are illustrated in this example the angular characteristics for vertical reflection of incident light ratio respectively, the wavelength characteristic of reflectance, and for the wavelength characteristic of 60 ° of reflection of incident light ratios.
As Figure 19, Figure 20 and shown in Figure 21,, can obtain good characteristic according to this example.Particularly, as Figure 20 and shown in Figure 21, transmittance and 60 ° of reflection of incident light ratios have been improved for vertical incident light.
[second embodiment]
Below with reference to Figure 22 and Figure 23 the second embodiment of the present invention is described.This embodiment is the embodiment of glasses display.Here, with the difference of mainly describing with first embodiment.
Figure 22 be glasses display opticator along observer's surface level intercept schematic sectional view.As shown in figure 22, the opticator of this glasses display comprisesimage input block 2 and planar substrates 11 (thisimage input block 2 has liquidcrystal display cells 21 and theobject lens 22 that are installed in wherein, and thisplanar substrates 11 has guidingcatoptron 11 and the half-reflectingmirror 11b that is installed in wherein).
In this glasses display, thereflective film 22a of reinforcement is separately positioned on the surface of observer's one side of thisplanar substrates 11 and on the outer surface, closely to contact with corresponding surface.
The function that thereflective film 22a of each enhancing has at least andalternative film 12a, 13a are same (function same) with air-gap.Specifically, thereflective film 22a of this enhancing will be to showing reflectivity properties (here by the figure transmission luminous flux L1 of inside surface reflection inplanar substrates 11, visible light with about 60 ° of incident angle incidents), and image transmission luminous flux L1 that will be by thisplanar substrates 11 and exterior light flux the L2 visible light of about 0 ° of incident angle incident (, with) are shown transmission property here.
But the ranges of incidence angles that the ranges of incidence angles of the visible light that thereflective film 22a of enhancing can reflect can reflect visible light thanalternative film 12a, 13a is wide, and specifically, the lower limit of incident angle is arranged to the critical angle θ less than this planar substrates 11C(40 ° of ≈) for example is arranged to 35 ° etc.Incident angle θgThe upper limit, be similar to eachalternative film 12a, 13a and, be about 90 ° as the aerialplanar substrates 11 of discrete component.
The ranges of incidence angles θ that has the image transmission luminous flux L1 that theplanar substrates 11 that strengthensreflective film 22a can the inside surface reflection on itgRanges of incidence angles when being present in the air as single element greater than this planar substrates 11.The ranges of incidence angles θ of this increasegObtain can be observed the image viewing angle of the increase observed of eyes.
If the lower limit of the ranges of incidence angles of the visible light that thereflective film 22a that strengthens can reflect is provided with too lowly, following problems will appear.Just, possible portion of external luminous flux L2 can not be by thereflective film 22a of this enhancing, cause very poor external visibility, perhaps can not be transmitted into outside (emergent pupil) fromplanar substrates 11, cause decay by the image of half-reflectingmirror 11b polarization transmission luminous flux L1.Therefore, the incident angle when considering the viewing angle of image transmission luminous flux L1 and its internal reflection can must be arranged on about 0 °~θ by the lower limit of the ranges of incidence angles of the visible light of thereflective film 22a of this enhancing reflectionCBetween.
And the enhancingreflective film 22a with this specific character is by insulativity optical multilayer film, HOE manufacturings such as (holographic optical elements (HOE)s).To describe the structure of the enhancingreflective film 22a that utilizes the insulativity optical multilayer film in the example that wherein is described below in detail.Make the method for HOE and the basic identical (see figure 4) of in first embodiment, describing of manufacture method.
But, in this manufacture method, as shown in figure 23, only insert auxiliary prism 32 (this is because one of two media that contacts with thereflective film 22a that strengthens is an air in this embodiment) in one of laser beam on being incident on photochromics.
And thereflective film 22a that the value of angle θ in the optical system of Figure 23 (being incident on the incident angle of the laser beam on this holography photochromics 35) is arranged to drop on this enhancing shows in the ranges of incidence angles of light of reflectivity properties it.
Here, the incident angle that thereflective film 22a of this enhancing shows the pairing light of reflectivity properties is different with wavelength, and therefore, thisphotochromics 35 is by multiexposure, multiple exposure when the angle θ of this laser beam and wavelength variations.
And, utilize resin-based materials (resin sheet) can low-costly make and have large-area HOE as holographic photochromics 35.Also have,, only this HOE is closely contacted with theplanar substrates 11 of this glasses display, have very high practical value according to reducing cost and producing it in batches by pasting HOE if HOE is a resin sheet.
And, as thereflective film 22a of the enhancing of this embodiment, can use by metallic film, semiconductive thin film etc. and make multilayer optical film.But compare with such multilayer optical film, the insulativity optical multilayer film absorbs less light, is preferred therefore.
It is desirable for above-described optical function unit (insulativity optical multilayer film, HOE and other multilayer optical films) according to the specification of glasses display, cost etc. optionally as thereflective film 22a that strengthens.
The 6th example
The 6th example will be described below.This this example is the example of insulativity optical multilayer film, and this insulativity optical multilayer film is suitable for thereflective film 22a as the enhancing of the glasses display of second embodiment.
In this example, suppose that the light source of the liquidcrystal display cells 21 of glasses display has emission spectrum (having redness, green and blue peak respectively), and the light source of this liquid crystal display cells is a polarized light source.And, in this example, use method with computing machine automatic Synthesis membrane structure.
The membrane structure of the insulativity optical multilayer film of this example is shown in Figure 24.
As shown in figure 24, the sum of layer is 51, and the refractive index ofplanar substrates 11 is 1.60, and the refractive index of high refractive index layer H is 2.3, and the refractive index of index layer L be 1.46.
The N-SK14 that SCHOTT makes is as planar substrates, TiO2, Ta2O5Or Nb2O5Be used under the film deposition conditions of regulating, forming high refractive index layer H, SiO2Be used under the film deposition conditions of regulating, forming low-index layer L.
The insulativity optical multilayer film that Figure 25 illustrates this example is to the wavelength characteristic with the reflection of light ratio of small incident (0 °~20 ° of incident angles) incident.In Figure 25, Ra (0 °), Ra (5 °), Ra (10 °), Ra (15 °) and Ra (20 °) are the reflection of incident light ratios with 0 °, 5 °, 10 °, 15 ° and 20 ° (each is the mean value to the reflectance of the p-polarization part of the reflectance of the s-polarization part of incident light and incident light) incident angles.
Be clear that from Figure 25, if the incident angle of incident light 0 °-20 ° in scope, the insulativity optical multilayer film of this example shows 80% or above transmission property to the incident light in the whole visible spectrum.
The insulativity optical multilayer film that Figure 26 illustrates this example is to the wavelength characteristic of reflection of light ratio with big incident angle (35 ° of incident angles, 40 °).In Figure 26, Rs (35 °) and Rs (40 °) are that reflection of light with the incident angle incident of 35 ° and 40 ° is than (each is the reflectance to the s-polarization part of incident light).
As what be clear that from Figure 26, if the incident angle of incident light is 40 °, the insulativity optical multilayer film of this example shows 100% reflectivity properties basically to the s-polarized light in the whole visible spectrum.And for the s-polarized light with 35 ° of incident angles, it shows 80% or above reflectivity properties to appropriate section red in the visible spectrum, green and blue (460,520,633 nanometer).
The insulativity optical multilayer film that Figure 27 illustrates this example is to the angular characteristics of reflection of light ratio with respective wavelength.In Figure 27, Rs (633 nanometer) and Rs (520 nanometer) and Rs (460 nanometer) are respectively that reflection of light to the light with 633 nanometers, 520 nanometers and 460 nanometers (red, green and blue) is than (each is the reflectance to the s-polarization part of this incident light).
As shown in figure 27, if their incident angle be 35 ° or more than, the insulativity optical multilayer film of this example shows 80% or above reflectivity properties to the light of the redness in the visible spectrum, green and blue appropriate section.
As mentioned above, 35 ° is that the insulativity optical multilayer film of this example shows the lower limit of ranges of incidence angles of the visible light (, being red, green and blue s-polarized light) of reflectivity properties here to it.This angle is less than the critical angle θ of thisplanar substrates 11 of supposing in this exampleC, θC=38.7 °.
Therefore, in the glasses display of the insulativity optical multilayer film that utilizes this example as thereflective film 22a that strengthens, the image transmission luminous flux L1 ranges of incidence angles θ of inside surface reflection in thisplanar substrates 11gLower limit less than this critical angle θC, θC=38.7 °, than 35 ° big 3.7 °.
As a result, this glasses display can transmission with ranges of incidence angles θgThe image transmission luminous flux L1 of interior incident angle incident, θg=35 °-36 °, that is to say that image transmission luminous flux L1 has 30 ° of viewing angles.
And, as shown in figure 25, the insulativity optical multilayer film of this example has high transmittance for the visible light with little incident angle (0 °~20 °) incident, so that can guarantee the external visibility of glasses display, and the image transmission luminous flux L1 that is incident on the emergent pupil fromplanar substrates 11 does not decay.
[the 3rd embodiment]
Below with reference to Figure 28 the third embodiment of the present invention is described.This embodiment is the embodiment of glasses display.Here, the difference of the main description and first embodiment.
Figure 28 is the schematic sectional view of the opticator of glasses display along observer's surface level intercepting.As shown in figure 28, glasses display is configured such that in the glasses display (see figure 2) of first embodiment, and thereflective film 22a of enhancing is set, rather thanalternative film 12a, 13a.
Thereflective film 22a of each enhancing has the function same with second embodiment.That is to say, thereflective film 22a of this enhancing to the lower limit of the ranges of incidence angles of the visible light of its performance reflectance less than the critical angle θ ofplanar substrates 11C
Therefore, this glasses display is similar to the effect that first embodiment can provide diopter to proofread and correct, and in addition, is similar to second embodiment, and the effect that strengthens viewing angle can be provided.
Under the situation that the reflective film that strengthens is made with HOE, the manufacture method (see figure 4) of describing among its manufacture method and first embodiment is identical.
But thereflective film 22a that the value of angle θ in the optical system of Fig. 4 (being incident on the incident angle of the laser beam on the holographic photochromics) is arranged in this enhancing shows in the scope of incident angle of light of reflectivity properties it.
Here, the incident angle that thereflective film 22a of this enhancing shows the pairing light of reflectivity properties is different with wavelength, and therefore, when this laser beam angle θ and wavelength changed as required, this photochromics carried out multiexposure, multiple exposure.
The 7th example
Below the 7th example will be described.This example is the example of insulativity optical multilayer film, and this insulativity optical multilayer film is suitable for thereflective film 22a as the enhancing of the glasses display of the 3rd embodiment.
In this example, suppose that the light source of the liquidcrystal display cells 21 of this glasses display is a polarized light source.And, in this example, use method with this membrane structure of computing machine automatic Synthesis.
The membrane structure of the insulativity optical multilayer film of this example is shown in Figure 29.
As shown in figure 29, the sum of layer is 44, and the refractive index ofplanar substrates 11 is 1.56, and the refractive index of high refractive index layer H is 2.3, and the refractive index of index layer L be 1.46.
This planar substrates is the same with low-index layer with the 4th example, and TiO2, Ta2O5Or Nb2O5Be used under the film deposition conditions of regulating, forming high refractive index layer H.
The insulativity optical multilayer film that Figure 30 illustrates this example is to the wavelength characteristic with the reflection of light ratio of little incident angle (0 °~20 ° of incident angles) incident.In Figure 30, Ra (0 °), Ra (10 °) and Ra (20 °) are the reflection of light ratios with 0 °, 10 ° and 20 ° (each is the mean value to the reflectance of the p-polarization part of the reflectance of the s-polarization part of this incident light and this incident light) incident angle incidents.
As what be clear that from Figure 30, if the incident angle of incident light in 0 °~20 ° scope, the insulativity optical multilayer film of this example shows 70% or above transmission property to the incident light in the whole visible spectrum.
The insulativity optical multilayer film that Figure 31 illustrates this example is to the wavelength characteristic of reflection of light ratio with big incident angle (35 °~50 ° of incident angles).In Figure 31, Rs (35 °), Rs (40 °) and Rs (50 °) are that reflection of incident light with the incident angle incident of 35 °, 40 ° and 50 ° is than (each is the reflectance to the s-polarization part of this incident light).
As shown in figure 31, if incident angle is the insulativity optical multilayer film of 35 °~50 ° of these examples the light of whole visible spectrum is basically shown 65% or above reflectivity properties.
The insulativity optical multilayer film that Figure 32 illustrates this example is to the angular characteristics of reflection of light ratio with respective wavelength.Rs in Figure 32 (633 nanometer) and Rs (520 nanometer) and Rs (460 nanometer) are respectively than (each is the reflectance to the s-polarization part of incident light) to reflection of light with 633 nanometers, 520 nanometers and 460 nanometers (red, green and blue).
Shown in figure 32, if its incident angle is 35 ° or bigger, the insulativity optical multilayer film of this example shows 65% or above reflectivity properties to the light of the redness in the visible spectrum, green and blue each several part.
Just, 35 ° is that the insulativity optical multilayer film of this example shows the lower limit (having the s-polarized light that wavelength is 663 nanometers, 520 nanometers and 460 nanometers here) of ranges of incidence angles of the visible light of reflectivity properties to it.This angle is less than the critical angle θ of the planar substrates of supposing in this example 11 (refractive index 1.56)C, θC=39.9 °.
Therefore, in the glasses display of the insulativity optical multilayer film that utilizes this example as thereflective film 22a that strengthens, the incident angle range Theta of the image transmission luminous flux L1 of inside surface reflection in thisplanar substrates 11gLower limit less than 39.9 ° critical angle θC, be 35 °, than this critical angle θCLittle 4.9 °.
And, as shown in figure 30, the insulativity optical multilayer film of this example has high transmittance for the visible light with little incident angle (0 °~20 °) incident, so that can guarantee the external visibility of glasses display, and the image transmission luminous flux L1 that is incident on the emergent pupil fromplanar substrates 11 does not decay.
[the 4th embodiment]
Below with reference to Figure 33 the fourth embodiment of the present invention is described.This embodiment is the embodiment of glasses display.In this embodiment, the reflective film of aforementioned enhancing is applied to have the glasses demonstration of big emergent pupil.
Figure 33 is the schematic sectional view of the opticator of this glasses display along observer's surface level intercepting.As shown in figure 33, this glasses display has a plurality of half-reflectingmirror 11b that are parallel to each other, and these a plurality of half-reflecting mirrors are arranged in theplanar substrates 11 that image transmission luminous flux L1 reflects by inside surface therein.Each of these a plurality of half-reflectingmirror 11b reflects the light in this image transmission luminous flux of the incident angle incident in the scope at a predetermined angle, by by surface reflection, and each half-reflectingmirror 11b is formed on the outer emergent pupil of thisplanar substrates 11 to this luminous flux in this planar substrates 11.Therefore, the size of this emergent pupil is increased by these a plurality of half-reflectingmirror 11b are provided.According to the degree of freedom of the position that strengthens the pupil of observing eyes, this big emergent pupil is favourable.
In this glasses display, thereflective film 22a of enhancing is respectively formed on the surface of observer's one side of thisplanar substrates 11 and on the outer surface, so as with its tight contact.As in the above-described embodiments, thereflective film 22a of this enhancing increases the scope of incident angle, makes that image transmission luminous flux can inside surface reflection in this planar substrates 11.Therefore, the viewing angle of this glasses display is increased.
[the 5th embodiment]
Below with reference to Figure 34 the fifth embodiment of the present invention is described.In this embodiment, the reflective film of aforementioned enhancing is applied to have the glasses demonstration of big emergent pupil.
Figure 34 is the schematic sectional view of the opticator of this glasses display along observer's surface level intercepting.As shown in figure 34, in this glasses display, a plurality of half-reflectingmirror 11b that are used to form big emergent pupil are arranged on the outside of planar substrates 11.These a plurality of half-reflecting mirrors are arranged in theplanar substrates 12, and thisplanar substrates 12 is arranged on (outside among Fig. 4) on the outside or observer's one side.And these a plurality of half-reflecting mirrors are formed by two kinds, promptly be parallel to each other a plurality of half-reflectingmirror 11bLBe parallel to each other and on attitude, be different from this a plurality of half-reflectingmirror 11bLA plurality of half-reflectingmirror 11bR
Inplanar substrates 11 inboards, directingmirror 11a is set and returnsmirror 11C, thislead catoptron 11a be used for will be incident on image transmission luminous flux L1 polarization on thisplanar substrates 11 to allowing this image to transmit the angle that luminous flux L1 is reflected by inside surface; This returnsmirror 11CReturn the image transmission luminous flux L1 that inplanar substrates 11, has been reflected by inside surface.
In a plurality of half-reflecting mirrors, half-reflectingmirror 11bLAttitude be arranged so that at the transmission of path epigraph forward luminous flux L1 and shaken, and other half-reflectingmirror 11b towards observer's one lateral deviationRAttitude be arranged so that at return path epigraph transmission luminous flux L1 and shake towards observer's one lateral deviation.Therefore, half-reflectingmirror 11bL, 11bRTotal be the half-reflecting mirror of roof shape, be arranged to mutual closure.
In this glasses display, the reflective film of enhancing is arranged betweenplanar substrates 12 and theplanar substrates 11, and on the surface of observer's one side of thisplanar substrates 11, with its tight contact.
Wherein, the film of thefilm 22a of the reflection of the enhancing on observer's one side of thisplanar substrates 11 and the reflection of above-described enhancing is the same, and the image transmission luminous flux L1 that is reflected by inside surface in thisplanar substrates 11 is shown reflectivity properties.
On the other hand, thereflective film 22a ' of the enhancing on the outside of thisplanar substrates 11 is slightly different with the film of above-described enhancing reflection, and the image transmission luminous flux L1 that is reflected by inside surface in thisplanar substrates 11 is shown half transmitting character.
Specifically, thefilm 22a ' that strengthens reflection to 11 image transmission luminous flux L1 by this planar substrates and exterior light flux L2 (here, visible light with about 0 ° of incident angle incident) shows transmission property (all transmissions), and the image that reflected by the inside surface transmission luminous flux L1 visible light of about 60 ° of incident angle incidents (, with) is shown half transmitting character here in this planar substrates 11.Its lower limit that shows the ranges of incidence angles of half transmitting character light is set to critical angle θ less than thisplanar substrates 11CValue.
Because the half transmitting character of thereflective film 22a ' that strengthens, a certain proportion of image transmission luminous flux L1 reciprocal inplanar substrates 11 propagates towardsplanar substrates 12 1 sides.The image transmission luminous flux L1 of this propagation is by a plurality of half-reflectingmirror 11b in theplanar substrates 12L, 11bRShake towards observer's one lateral deviation.Then by a plurality of half-reflectingmirror 11bL, 11bRThe image transmission luminous flux L1 of polarization is byreflective film 22a ', theplanar substrates 11 of this enhancing and thereflective film 22a that strengthens, to form big emergent pupil.
And, be similar to the foregoing description, thereflective film 22a of above-mentioned enhancing, the scope of 22a ' increase incident angle makes this image transmission luminous flux L1 be similar to the image transmission luminous flux L1 of the foregoing description, can be reflected by inside surface.Therefore, the viewing angle of this glasses display also is increased.
In this glasses display, be provided with and returncatoptron 11CWith two kinds of half-reflecting mirrors, still should be noted that and returncatoptron 11CWith half-reflectingmirror 11bRCan save.But, provide these catoptrons to make the light intensity in the emergent pupil even, therefore be more preferably.
[the 6th embodiment]
Below with reference to Figure 35 the sixth embodiment of the present invention is described.In this embodiment, the reflective film of aforementioned enhancing is applied to still have the glasses demonstration of big emergent pupil.
Figure 35 is the exploded view of opticator of the glasses display of this embodiment.As shown in figure 35, the principle same with the glasses display of the 5th embodiment is applied to this glasses display, and when when the observer observes, emergent pupil is expanded at vertical and horizontal both direction.And this glasses display also has the diopter calibration function.
In Figure 35, from the image transmission luminous flux L1 fromimage input block 2 emission at first be incident on planar substrates 11 ' on.This planar substrates 11 ' transmit luminous flux L1 with this image of planar substrates 12 ' guiding, and when the diameter of when the observer sees, vertically expanding this image transmission luminous flux L1.Image transmission luminous flux L1 is incident on the planar substrates 11.Thisplanar substrates 11 andplanar substrates 12 together navigational figure transmission luminous flux L1 to expand the diameter that this image transmits luminous flux L1 when along continuous straight runs when the observer sees.
And,planar substrates 13 is arranged on the observer's of thisplanar substrates 11 a side, and the realization of the optical function of the optical function of observation eyes one side surface of thisplanar substrates 13 and theseplanar substrates 12 outer surfaces is used for the diopter correction of the observation eyes of outside visual field.
With the same principle of theplanar substrates 11,12 of first embodiment be used to comprise planar substrates 11 ', 12 ' first optical system and comprise second optical system ofplanar substrates 11,12.And the direction that is provided with of the optical surface of first optical system is provided with the direction half-twist from the optical surface of second optical system
Specifically, planar substrates 11 ' in, Reference numeral 11a ' expression guiding catoptron, its will be incident on this planar substrates 11 ' on image transmission luminous flux L1 polarization to making this image transmit the angle that luminous flux L1 is reflected by inside surface, catoptron is returned in Reference numeral 11c ' expression, its return planar substrates 11 ' in the image transmission luminous flux L1 that reflected by inside surface.Planar substrates 12 ' in, the half-reflecting mirror (its details reference Figure 34) of mutually closed a plurality of roof shapes is arranged in Reference numeral 12a ' expression.
Inplanar substrates 11, Reference numeral 11a represents the catoptron that leads, its image that will be incident on thisplanar substrates 11 transmits luminous flux L1 polarization to the angle that this image transmission luminous flux L1 is reflected by inside surface, Reference numeral 11c represents to return catoptron, and it returns the image transmission luminous flux L1 that has been reflected by inside surface in planar substrates 11.Inplanar substrates 12, Reference numeral 12a represents to be arranged to the half-reflecting mirror (its details reference Figure 34) of closed mutually a plurality of roof shapes.
In above-mentioned glasses display, the reflective film of this enhancing be arranged on planar substrates 11 ' and planar substrates 12 ' between, planar substrates 11 ' and planar substrates 13 ' between, betweenplanar substrates 11 and theplanar substrates 12, betweenplanar substrates 11 and theplanar substrates 13.
But, be arranged on planar substrates 11 ' and planar substrates 12 ' between the reflective film of this enhancing need have make planar substrates 11 ' in a certain proportion of image transmission luminous flux L1 of being reflected by inside surface propagate by this planar substrates 11 ' to planar substrates 12 ' characteristic.This specific character is identical with the characteristic of thereflective film 22a ' of the enhancing of the 5th embodiment.
The reflective film that is arranged on the enhancing betweenplanar substrates 11 and theplanar substrates 12 also needs to have propagates by the characteristic of thisplanar substrates 11 toplanar substrates 12 a certain proportion of image transmission luminous flux L1 that is reflected by inside surface in planar substrates 11.This specific character is identical with the characteristic of thereflective film 22a ' of the enhancing of the 5th embodiment.
The reflective film of above-mentioned enhancing increases the scope of incident angle, makes the image transmission luminous flux L1 can be at planar substrates 11 ' reflected by inside surface, and the scope that increases incident angle can be reflected image transmission luminous flux L1 atplanar substrates 11 by inside surface.And, increase planar substrates 11 ' direction and increase direction atplanar substrates 11, the direction difference that makes both is 90 °.
Therefore, in this glasses display, the viewing angle vertically and the viewing angle of along continuous straight runs all are increased.
[the 7th embodiment]
Below with reference to Figure 36 the seventh embodiment of the present invention is described.In this embodiment, the reflective film of aforementioned enhancing is applied to the glasses demonstration that wherein many surfaces are used for internal reflection.
Figure 36 (a) is the perspective illustration of the opticator of glasses display.Figure 36 (b) is the schematic sectional view of this opticator along surface level (being observer's ZX plane among Figure 36 (a)) intercepting.Figure 36 (c) is the schematic sectional view of this opticator along plane (the YX plane of Figure 36 (a)) intercepting of observer front.Figure 36 d is the view that is used to illustrate the viewing angle of this glasses display.
As Figure 36 (a) and (b) with (c), in this glasses display, position and attitude be set by what regulate guidingcatoptron 11a and a plurality of half-reflectingmirror 11b, 4 surfaces altogether ofplanar substrates 11 are used to internal reflection.The surface that these four surfaces are observer's one sides, outer surface and by these two clip surfaces two surfaces therein.In addition, these four surfaces all are plane surfaces.
Figure 36 (d) illustrate when when the observer observes along the viewing angle θ b of the both direction of the image of this glasses display-air, θ a-air
Outside these, viewing angle θ b-airrBe by the angle θ b that image transmission luminous flux L1 can be reflected by inside surface on two surfaces-gDetermine that the surface and the outer surface of observer's one side that these two surfaces areplanar substrates 11 are shown in Figure 36 (b).
Viewing angle θ a-airBy the angle θ a that image transmission luminous flux L1 can be reflected by inside surface on two surfaces ofplanar substrates 11-gDetermine, shown in Figure 36 (c).
They are represented with following expression formula
θa-air=sin-1[ng?sin?θa-g]
θb-air=sin-1[ng?sin?θb-g]
That is to say, when image transmission luminous flux L1 can inside surface reflection inplanar substrates 11 angular range, theta a-g, θ b-gWhen becoming big, viewing angle θ a-air, θ b-airAlso become big.
In this glasses display, the reflective film of enhancing is arranged on four surfaces of thisplanar substrates 11, is used for internal reflection.In Figure 36 b, c,Reference numeral 22a represents the reflective film that strengthens.The characteristic of the characteristic of thereflective film 22a of this enhancing and thereflective film 22a of the enhancing in the foregoing description is same, and thereflective film 22a of this enhancing is lower than the critical angle θ of thisplanar substrates 11 to its lower limit of ranges of incidence angles that shows the visible light of reflectivity propertiesC
Therefore, make the angular range, theta a that image transmission luminous flux L1 can inside surface reflection inplanar substrates 11-g, θ b-g(Figure 36 b, c) is increased.As a result, the viewing angle θ a of this glasses display-air, θ b-air(Figure 36 d) also is increased.
In addition, thereflective film 22a of two enhancings that is shown in Figure 36 (c) does not therefore need transmission exterior light flux not towards observing eyes.Therefore, preferably, be used for each of reflective film of these two enhancings by the metallic film of manufacturings such as silver, aluminium, rather than said insulativity optical multilayer film in front or HOE.The use of metallic film can make viewing angle θ a-airGreater than viewing angle θ b-air
Therefore, if the aspect ratio of liquidcrystal display cells 21 is not 1: 1, it is to grow the viewing angle of a side corresponding to viewing angle θ a that this liquidcrystal display cells 21 preferably is arranged to-air
In addition, theplanar substrates 11 of this glasses display is the substrate with cylindricality of square-section, but, also can use cylindricality substrate with difformity cross section, the cylindricality substrate that for example has the triangular-section, cylindricality substrate with parallelogram section has the cylindricality substrate of pentagonal section.
[the 8th embodiment]
Ginseng is described the eighth embodiment of the present invention according to Figure 37, Figure 38, Figure 39, Figure 40, Figure 41 and Figure 42 below.This embodiment is the embodiment of glasses display.Here the difference of the main description and first embodiment.
Figure 37 is the outside drawing of this glasses display.Coordinate system among Figure 37 is the XYZ cartesian corrdinate system of the right-hand rule, and wherein, if the observer who wears glasses from the beginning sees that directions X points to down, the Y direction is pointed to right.In the following description, the direction represented of XYZ coordinate system or by see from the observer by about up and down the direction of expression will use as required.
As shown in figure 37, the image displayoptical system 1 of glasses display have minimizing from outside visual field the minimizing function to the exterior light flux of observing eyes (observer's right eye) guiding.
And, for balance from outside visual field to the light intensity of the exterior light flux of observing the eyes guiding and from outside visual field to the light intensity of the exterior light flux of non-observation eyes (observer's left eye) guiding, and left and right outward appearance for the balance glasses display, the front of non-observation eyes one side also has the light that is similar to image displayoptical system 1 and reduces function, and has the front that is attached to non-observation eyes with theplanar substrates 5 of image displayoptical system 1 same outward appearance.This shall not be applied to the situation that does not need the outside luminous flux of balance and do not need the balance outward appearance.
Figure 38 be glasses display optical system detail drawing and along the branch schematic sectional view of the optical system portion of this glasses display of the planar interception that is parallel to the YZ plane.
In Figure 38, Reference numeral 20a represents to comprise the lamp optical system of led light source, catoptron etc., and this lamp optical system does not illustrate in first embodiment.
As shown in figure 38, image displayoptical system 1 comprises theplanar substrates 11 that visible light is at least had transmission property.In the precalculated position ofplanar substrates 11, the guidingcatoptron 11a and the half-reflectingmirror 11b that are similar to first embodiment are arranged to predetermined attitude.As in first embodiment, the possible another kind of scheme of half-reflectingmirror 11b is a polarization optical film, and for example transmission comprises the polarization beam splitter or the holographic optics film of the exterior light flux of visible light.
On theouter surface 1b ofplanar substrates 11, form thedim light film 20 that reduces exterior light flux L2 with predetermined minimizing ratio.The function of thisdim light film 20 is to reduce the brightness of external image with predetermined ratio.
The object lesson ofdim light film 20 will be described below.
As the material of general dim light film, used is hardware, for example aluminium (Al), chromium (Cr), tungsten (W) or rhodium (Ro), or inconel etc.
But these materials have optical absorption property (absorbance), and therefore, if do not consider to providedim light film 20 onplanar substrates 11, a certain amount of image transmission luminous flux L1 of the reflection of the inside surface inplanar substrates 11 will be absorbed by thisdim light film 20 so.Just, the light intensity of the light path of image transmission luminous flux L1 will be subjected to very big loss.
Therefore, in order to prevent the decay of light intensity, by the double-layer films that overlaps of silver (Ag) film and thin dielectric film as thedim light film 20 among this embodiment.The basic structure of dim light film is as follows:
Planar substrates/Ag/0.25L/ air, wherein
Ag: silver (silver layer),
L: low-refraction dielectric (L layer), and
The digital value in L layer left side: the bed thickness of L layer (centre wavelength of used wavelength coverage).
In this basic structure, the L layer is used for protecting the silver layer surface that is subjected to the air erosion and improves the reflection of light ratio with big incident angle incident.
The details of dim light film 20 (specification) is as follows:
Transmittance is set: 30% (for 0 degree incident angle),
Central wavelength lambdaC: 500 nanometers,
The refractive index of planar substrates: 1.56,
The bed thickness of silver layer: 30 nanometers, and
The refractive index of L layer: 1.46.
In addition, as single element, the optical constant of silver layer is shown in Figure 39 and Figure 40.Figure 39 illustrates the wavelength characteristic as the refractive index of the silver layer of single element, and Figure 40 illustrates the wavelength characteristic as the extinction coefficient of the silver layer of single element.
The reflectance ofplanar substrates 11 1 sides ofdim light film 20 and the wavelength characteristic of transmittance (0 ° of incident angle, 45 °) are shown in Figure 41.And the reflectance ofplanar substrates 11 1 sides ofdim light film 20 and the angular characteristics of transmittance (wavelength 550 nanometers) are shown in Figure 42.
In Figure 41 and Figure 42, " R " represents reflectance, and " T " expression transmittance.The subscript of reflectance or transmittance " p " expression is to the characteristic of p-polarization part, and the subscript of reflectance or transmittance " s " expression is to the characteristic (this also is applicable to other accompanying drawings) of s-polarization part.
As from Figure 41 and Figure 42 finding clearly, thisdim light film 20 shows 100% reflectance basically for the visible light with the s-polarization part of 40 ° or bigger incident angle incident.And thisdim light film 20 shows about 30% transmittance for the visible light with 0 ° of incident angle incident.
Therefore,dim light film 20 reduce images transmission luminous flux L1 light path light intensity decay and only reduce exterior light flux L2 in the visible spectrum with about 70% minimizing ratio.
At this moment, keep the brightness of the image (display image) of observation eyes observation, and the brightness of external image reduces about 30%.Therefore, when outside visual field is when becoming clear, the observability of display image is enhanced certainly.Therefore select the film of suitable type to make it possible to obtain desirable effect according to the reflectance-transmittance characteristic ofdim light film 20 according to incident angle with the structure of minimum.
Though the basic structure of thedim light film 20 of this embodiment is double-layer structures of silver layer and dielectric layer, also can replace silver layer with other metal levels, perhaps also can adopt two dielectric layers to clip the three-decker of a metal level.But the double-layer structure of silver layer and dielectric layer can be than the characteristic that is easier to provide good (only reduce exterior light flux L2 and do not increase the characteristic of the decay of image transmission luminous flux LI).
[first of the 8th embodiment revises example]
Describe first of the 8th embodiment according to Figure 43 and Figure 44 below and revise example.
This revises example is the modification example ofdim light film 20.
This dimlight film 20 of revising example is only made by dielectric.In thisdim light film 20, every layer thickness is arranged to so that the catoptrical phase place on the interface of each layer has the relation of being wanted, and according to catoptrical phase relation, various characteristics can be set.Therefore, it is bigger than thedim light film 20 of the 8th embodiment the degree of freedom of transmittance to be set.This dimlight film 20 has following three kinds of basic structures:
Planar substrates/(0.25H0.25L)P/ air
Planar substrates/(0.125H0.25L0.125H)P/ air and
Planar substrates/(0.125L0.25H0.125L)P/ air, wherein
H: high index of refraction dielectric (H layer)
L: low-refraction dielectric (L layer)
The numerical value in every layer of left side: the thickness of every layer optical layers (centre wavelength of used wavelength coverage), and
P: the lamination number of the layer group of having been drawn together by bracket.
According to these basic structure, can reduce to certain optical transmission than and improve certain reflection of light ratio.
But in order to ensure the brightness that reduces external image, essential structuredim light film 20 is to be provided with the different multiple circulation layer group of centre wavelength, so that increase the light wavelength scope that can reduce its transmittance, up to whole visible spectrum.
And, in order to reduce the variation of the transmittance that depends on color, must be optimized by the bed thickness of computing machine to all layers.
The details (specification) of the dim light film after optimizing is as follows:
Transmittance is set: 5%
Central wavelength lambdaC: 480 nanometers
The refractive index of planar substrates: 1.583
The refractive index of H layer: 2.3
The refractive index of L layer: 1.46, and
The sum of layer: 22.
The structure of thisdim light film 20 is shown in Figure 43.
The N-BAF3 that planar substrates is made with SCHOTT, H layer and L layer H layer identical and L layer with the 6th embodiment.
The wavelength characteristic of the transmittance of thisdim light film 20 is shown in Figure 44.
As shown in figure 44,20 pairs of visible lights of this dim light film show about 5% transmittance.Therefore, according to this modification example, the brightness of external image reduces to about 5%.
[second of the 8th embodiment revises example]
Followingly describe second of the 8th embodiment according to Figure 45 and Figure 46 and revise example.
This revises example is the modification example ofdim light film 20.
This transmittance that is provided with of revising thedim light film 20 of example is 15%.This dimlight film 20 is also only by the dielectric manufacturing, and the basic structure of its basic structure and the first modification example is identical.
The details of this dim light film 20 (specification) is as follows:
Transmittance is set: 15%
Central wavelength lambdaC: 480 nanometers
The refractive index of planar substrates: 1.583
The refractive index of H layer: 2.3
The refractive index of L layer: 1.46, and
The sum of layer: 18.
The structure of thisdim light film 20 is shown in Figure 45.And, use with first of this embodiment and revise the example identical materials.
The wavelength characteristic of the transmittance of thisdim light film 20 is shown in Figure 46.
As from what Figure 46 was clear that, 20 pairs of visible lights of this dimlight film show 15% transmittance.Therefore, revise example according to this, the brightness of external image reduces to about 15%.
[revising replenishing of example]
Internal reflection condition in view ofplanar substrates 11, under this condition, discuss first and revise thedim light film 20 that example and second is revised example, guarantee the brightness of display image, that is to say, under this condition, realize about 100% reflection for the image transmission luminous flux L1 that in this planar substrates, is reflected by inside surface.
At first, suppose the state that dimlight film 20 is not set onplanar substrates 11, shown in Figure 47 (a).
According to the Snell law following expression, wherein n are proposed0Be theseplanar substrates 11 existence and air wherein refractive index as the air of medium, ngBe refractive index as the glass of planar substrates material, and θ0, θgBe the incident angle of light on thisplanar substrates 11 and this medium.
n0?sin?θ0=ng?sin?θg
Therefore, the critical angle θ of thisplanar substrates 11 in this stateC(minimum value of the incident angle of the light of permission inside surface reflection) represented by following expression formula:
θc=arc?sin(n0/ng)
Below, suppose the state that the dim light film of being made by the multilayerthin dielectric film 20 is set onplanar substrates 11, shown in Figure 47 (b).If every layer of these multilayer film does not have absorbability (zero absorbability), proposes following expression formula, wherein n according to the Snell law1, n2NkBe the refractive index of this each layer of multilayer film, and θ1, θ2θkBe the incident angle of light on each layer.
n0?sinθ0=n1sinθ1
=n2sinθ2
……
=nksinθk
=ngsinθg
Therefore, if every layer of these multilayer film does not have absorbability, the critical angle θ ofplanar substrates 11 socSame expression formula by the state that dimlight film 20 is not provided is represented.
Therefore, no absorbability dielectric is as thedim light film 20 of first example and second example.
In addition, the angular characteristics of the reflectance ofplanar substrates 11 1 sides of the dim light film (reflectance of the internal reflection of planar substrates 11) of the dielectric first modification example of the no absorbability of utilization and the second modification example is shown in Figure 48.
As shown in figure 48,20 pairs of this dim light films show about 100% reflectance with the light of 45 ° or bigger incident angle incident.
[the 3rd of the 8th embodiment revises example]
Following the 3rd modification example of describing the 8th embodiment according to Figure 49, Figure 50, Figure 51, Figure 52 and Figure 53.
This revises example is the modification example ofdim light film 20.
This dimlight film 20 of revising example has anti-ultraviolet and infrared function.
This dim light film is also only used the dielectric manufacturing, and the structure of its basic structure and the first modification example and the second modification example is identical.
Revise in the example at this, for ultraviolet and infrared protection function are provided, absorbefacient dielectric is really as the H layer.Utilize titania (TiO2) as the absorbability dielectric.
Titania (TiO2) optical constant be shown in Figure 49 and Figure 50.Figure 49 illustrates titania (TiO2) the wavelength characteristic of refractive index, and Figure 50 illustrates titania (TiO2) extinction coefficient wavelength characteristic.
The details of this dim light film 20 (specification) is as follows:
Transmittance is set: 30%
Central wavelength lambdaC: 800 nanometers
The refractive index of planar substrates: 1.583
The refractive index of L layer: 1.46, and
The sum of layer: 48.
The structure of thisdim light film 20 is shown in Figure 51.And, revise the example identical materials with first of this embodiment and be used for this planar substrates and L layer.
The wavelength characteristic of the transmittance of thisdim light film 20 is shown in Figure 52.The reflectance characteristic (reflectance of the internal reflection of this planar substrates 11) ofplanar substrates 11 1 sides of thedim light film 20 of this modification example is shown in Figure 53.
Shown in Figure 53, the curve indention of the wavelength characteristic of reflectance (valley of reflectance).
On the other hand, the emission wavelength characteristics curve of the liquidcrystal display cells 21 of this glasses display has peak value usually in red, green and blue respective wavelength.
Therefore, finely tune the structure that this revises thedim light film 20 of example, so that the valley of the curve of the wavelength characteristic of reflectance departs from the peak value of this emission wavelength characteristics curve.
As a result, each the wavelength part that is included among this image transmission luminous flux L2 reflects with the high reflectance inside surface in thisplanar substrates 11 undoubtedly.Therefore guarantee the brightness of display image.
In addition, seen in Figure 53, the form that the curve valley of the curve of s-polarization part and p-polarization part takes place is different.Specifically, the valley that takes place in the curve of p-polarization part is smaller.
Therefore, be applied under the situation of glasses display, be limited in p-polarization part, can guarantee that the valley with the wavelength characteristic curve of reflectance departs from the peak value of emission wavelength characteristics curve by image being transmitted luminous flux at thisdim light film 20.
In addition, because the principle of liquid crystal display cells, this image transmission luminous flux L1 is polarized, therefore, by optimizing the position relation of this liquidcrystal display cells 21 andplanar substrates 11, so that its polarization direction becomes the p-polarization direction with respect to this dim light film, perhaps go up and insert phase-plate by following stages (stage) at this liquidcrystal display cells 21, can only image be transmitted luminous flux L1 and be constrained to p-polarization part.
[the 9th embodiment]
Below with reference to Figure 54, Figure 55, Figure 56 and Figure 57 the ninth embodiment of the present invention is described.
This embodiment is the embodiment of glasses display.Here, difference with the 8th embodiment is only described.
Figure 54 is the outside drawing of this glasses display.Coordinate system is a right-hand rule XYZ Cartesian coordinates in Figure 54, if wherein from the observer, directions X points to down, and the Y direction is pointed to right.In the following description, see with the direction of representing up and down and will use as required with the direction of XYZ coordinate system description or from the observer.
Shown in Figure 54, the difference of the glasses display of this glasses display and the 8th embodiment is that the light minimizing ratio of the central area of close half-reflectingmirror 11b is arranged to reduce ratio greater than the light of the neighboring area outside the central area of this image displayoptical system 1 in image displayoptical system 1.
And, for balance from outside visual field to the light intensity of the exterior light flux of observing eyes (observer's right eye) guiding and from outside visual field to the light intensity of the exterior light flux of non-observation eyes (observer's left eye) guiding, in addition, left and right sides outward appearance for the balance glasses display, the front of non-observation eyes one side has the image of the being similar to display optical 1 dim light function of uniting, withplanar substrates 5, thisplanar substrates 5 has the outward appearance same with this image displayoptical system 1.
Figure 55 is the details of the opticator of this glasses display, and is the schematic sectional view of the opticator of this glasses display along the planar interception that is parallel to the YZ plane.
Shown in Figure 55, image transmission luminous flux L1 in this glasses display and the state of exterior light flux L2 are the same with the 8th embodiment (seeing Figure 38).
On the outer surface of theplanar substrates 1b of composing images displayoptical system 1, be provided with the 8th embodiment or its and revise the samedim light film 20 of example.
But the dim light film of being made by multiple layer metal film orthin dielectric film 40 overlaps the center on thesedim light film 20 surfaces.
Therefore, the light in the center of image displayoptical system 1 reduces ratio and reduces ratio greater than the light of the surrounding zone of this image displayoptical system 1.
In addition, the position of the half-reflectingmirror 11b that sees from position, central area that the observer sees with from the observer is essentially identical.And, from the size of this central area that the observer sees slightly greater than the size of the half-reflectingmirror 11b that sees from the observer.
In aforesaid this glasses display, the brightness of the external image of the background parts that image shows is reduced especially significantly, so that further strengthen the observability of this display image.
Below, the object lesson ofdim light film 20,40 will be described.
The multilayer thin dielectric film manufacturing that thesedim light film 20 usefulness are same with the modification example of the 8th embodiment.Dim light film 40 is also used the multilayer thin dielectric film manufacturing same with the modification example of the 8th embodiment.Also use the planar substrates same with the modification example of the 8th embodiment.
The details of this dim light film 20 (specification) is as follows:
Dim light film 20 transmittance is set: 50%
Dim light film 40 transmittance is set: 50%
Central wavelength lambdaC: 800 nanometers
The refractive index of planar substrates: 1.583
The refractive index of H layer: 2.3
The refractive index of L layer: 1.46
Total number of plies of dim light film 20: 11
Total number of plies of dim light film 40: 16
The structure ofdim light film 20,40 is shown in Figure 56.
The wavelength characteristic of the transmittance of the wavelength characteristic of the transmittance of the center ofdim light film 20,40 and the surrounding zone ofdim light film 20 is shown in Figure 57.
As Figure 57 clearly shown in, the transmittance of visible light center is about 25%, the transmittance of the surrounding zone of visible light is about 50%.
Therefore, according to this glasses display, it is about 50% that the brightness of whole external image image reduces to, and the external image of the background parts of this display image reduces to about 25%.
In this embodiment,dim light film 20 anddim light film 40 are overlapped, and be overlapped but they do not need.In this case, thedim light film 20 that has opening in the center is arranged on theplanar substrates 11, and dim light ratiodim light film 20 high dimlight films 40 are arranged in this opening.But, in this case, during formingdim light film 20 and formingdim light film 40, need mask, therefore,, wish that moredim light film 20 anddim light film 40 are overlapped in order to reduce manufacturing cost.
[first of the 9th embodiment revises example]
Describe first of the 9th embodiment according to Figure 58 and Figure 59 below and revise example.
This revises example is the modification example ofdim light film 20 anddim light film 40.
Thedim light film 40 of this modification example is made by metallic film.
This structure of revising thedim light film 20 of example is the same with structure shown in Figure 45.Have and same characteristic shown in Figure 46 as thisdim light film 20 of discrete component.
As for the structure ofdim light film 40, it comprises chromium (Cr) layer that 5mm is thick.Simultaneously, the wavelength characteristic of the center of thisdim light film 20,40 with the transmittance shown in Figure 58.
And the angular characteristics (characteristic of center) of the reflectance onplanar substrates 11 1 sides of this dim light film 20 (the internal reflection ratio of this planar substrates 11) is shown in Figure 59.
Shown in Figure 59, has high numerical value for s-polarization partial reflection ratio with the above-mentioned light of 40 ° or bigger incident angle incident.But, very low for the p-polarization reflectance partly of this light.Therefore be applied under the situation of glasses display at thisdim light film 20,40 of revising example, image transmission luminous flux L1 is limited in s-polarization part.
In addition, because the principle of liquidcrystal display cells 21, image transmission luminous flux L1 is polarized, therefore by optimizing the position relation of this liquidcrystal display cells 21 and thisplanar substrates 11, make its polarization direction become the s-polarization direction, perhaps, can only image be transmitted luminous flux L1 and be constrained to s-polarization part by on the following stages of this liquidcrystal display cells 21, inserting phase-plate.
[second of the 9th embodiment revises example]
Describe second of the 9th embodiment according to Figure 60 and Figure 61 below and revise example.
This revises example is the modification example of dim light film 20.This revises thedim light film 20 holographic optics thin film fabrication of example.
When making this holographic optics film, double expose.
Exposure is to be used to make this holographic optics film to have the exposure of transmission with the light characteristic of the incident of about 0 ° of incident angle for the first time, has predetermined transmittance.Current exposure for example occurs in the optical system shown in Figure 60.
Specifically, two luminous fluxes vertically are incident on the holographic photochromics 56.Optical attenuator inserts in one of them luminous flux.Transmission ratio can be by the damping capacity setting of optical attenuator 52.In Figure 60,51 expression LASER Light Source (can radiation wavelength be red, green and blue laser beam).BS represents the branch beam tube, and M represents catoptron, 53 expression optical beam expanders, and 55 expressions divide beam tube.
Exposure for the second time is the exposure that is used for guaranteeing the image in the reflection ofplanar substrates 11 inside surfaces is transmitted the reflectance of luminous flux L1.Current exposure for example occurs in the optical system shown in Figure 61.
Specifically, two luminous fluxes are incident on theholographic photochromics 56 with the identical angle of angle that the image with the reflection of inside surface inplanar substrates 11 transmits luminous flux L1.In Figure 61,51 expression LASER Light Source (can radiation wavelength be red, green and blue laser beam).BS represents the branch beam tube, and M represents catoptron, 53 expression optical beam expanders, and 57 expressions divide beam tube.
After the double exposure,holographic photochromics 56 is developed, and is the breath optical thin film so that finish.
Finish the holographic optics film like this and have the function that dimlight film 20 need have.
Though this revises the modification example that example is thedim light film 20 made by the holographic optics film, thisdim light film 20 anddim light film 40 can be made of a kind of holographic optics film.
In the manufacturing of this holographic optics film, exposure is for the first time carried out with two steps of separating.
In step of exposure, the central area of holographic optics film is exposed (neighboring area crested) therein, in another step of exposure, this neighboring area be exposed (this central area crested).
In these two step of exposure, the damping capacity of optical attenuator 52 is set to different value.Therefore, the transmittance of the transmittance of the center of this holographic optics film and neighboring area is set to different value.
[the tenth embodiment]
According to Figure 62, Figure 63, Figure 64, Figure 65 and Figure 66 the tenth embodiment of the present invention is described below.
This embodiment is the embodiment of glasses display.Here, the difference of a description and the 8th embodiment.
Figure 62 is the outside drawing of this glasses display.The coordinate system of Figure 62 is the XYZ cartesian corrdinate system of the right-hand rule, and wherein, if from the observer, directions X points to down, and the Y direction is pointed to right.In the following description, the direction of representing by the XYZ coordinate system or will use as required by the direction of seeing from the observer of expression up and down.
Shown in Figure 62, the outward appearance (seeing Figure 37) of the outward appearance of this glasses display and the 8th embodiment is basic identical.
Figure 63 is the detail drawing of this glasses display, and is the schematic sectional view of the opticator of this glasses display along the planar interception that is parallel to the YZ plane.
Shown in Figure 63, image transmission luminous flux L1 in this glasses display and the state of exterior light flux L2 and the state (seeing Figure 38) of the 8th embodiment are same.
First opticalthin film 60 is arranged on theouter surface 1b of planar substrates 11.Secondplanar substrates 70 by the optical glass manufacturing is arranged on the surface of this first optical thin film 60.Second opticalthin film 80 also sticks on this surface of twoplanar substrates 70.
This first opticalthin film 60 is to act on thisplanar substrates 11 with the same mode of air-gap.Specifically, the side interface of theplanar substrates 11 of this first opticalthin film 60 is with 100% reflectance reflected image transmission luminous flux L1 basically.And, first optical thin film, 60 transmission exterior light flux L2.In addition, first optical thin film can have function and anti-ultraviolet or the infrared function that reduces visible light.
This secondplanar substrates 70 and second opticalthin film 80 have the function that reduces exterior light flux L2.In addition, this secondplanar substrates 70 and second opticalthin film 80 can have function and anti-ultraviolet or the infrared function that reduces visible light.
In this glasses display, the function of first opticalthin film 60 is guaranteed the reflectance to the image transmission luminous flux L1 of the reflection of inside surface inplanar substrates 11, and it is optional to the reflectance of this image transmission luminous flux L1 that therefore secondplanar substrates 70 and second opticalthin film 80 have enhancing.
Therefore, it is very big to construct the degree of freedom of this secondplanar substrates 70 and second optical thin film 80.For example the emergent light optical light filter glass of any kind can be applied to this secondplanar substrates 70.
Therefore, secondplanar substrates 70 and second opticalthin film 80 can have higher dim light function.
High dim light function is meant, for example, the variation of getting in the dim light ratio of incident angle of determining is very little, depends on that the variation of dim light ratio of wavelength is very little etc.
The object lesson of first optical thin film will be described below.The situation that image transmission luminous flux is limited in s-polarization part here will be described.
The structure of first opticalthin film 60 is as follows:
Planar substrates/(0.125L0.28H0.15L) (0.125L0.25H0.125L)4(0.15L0.28H0.125L)/second planar substrates, wherein
H: high index of refraction dielectric (H layer)
L: low-refraction dielectric (L layer)
Digital value on every layer of left side: every layer bed thickness (centre wavelength of used wavelength coverage) and
Subscript numeral: the overlapping number of layer group in the bracket.
The details of first optical thin film 60 (specification) is as follows:
0169 central wavelength lambdaC: 850 nanometers,
The refractive index of planar substrates: 1.56,
The refractive index of H layer: 2.30
The refractive index of L layer: 1.46
The refractive index of second planar substrates: 1.507,
The extinction coefficient of second planar substrates=0.01.
In addition, the extinction coefficient of secondplanar substrates 70 is arranged to big value, for example 0.01, its objective is by utilize refractive index as secondplanar substrates 70 be 1.50 and thickness for various types of optical lightscreening glass of 1mm, secondplanar substrates 70 with various dim light characteristics and wavelength break-in facility is provided.
Figure 64 illustrate refractive index be 1.50 and thickness be the extinction coefficient k of calculating of glass substrate of 1mm and the correction between the transmittance.
Can see that from Figure 64 the maximal value of actual extinction coefficient k is 0.01.
Therefore, the extinction coefficient of secondplanar substrates 70 is set to 0.01 makes whichever optical filter glass as secondplanar substrates 70, can both construct effective first opticalthin film 60.
The wavelength characteristic of the reflectance ofplanar substrates 11 1 sides of first optical thin film (0 ° of incident angle, 60 °) is shown in Figure 65.
And the angular characteristics of the reflectance of second planar substrates, 70 1 sides of first opticalthin film 60 is shown in Figure 66.
Shown in Figure 65 and Figure 66 clearly shown in, 60 pairs of s-polarizations with the visible light of 0 ° of incident angle incident of this first optical thin film partly show 10% or lower reflectance, and to the s-polarization with the visible light of 60 ° of incident angle incidents is partly shown 100% reflectance basically.
And as previously mentioned, any light filter glass can be used as second planar substrates 70.That is to say, any light filter glass of selling on the market, for example ultraviolet protection device, infrared protector, color filter and neutral light intensity light filter (to the light filter of dim light equably of all wavelengths in the visible spectrum) can both be applied to secondplanar substrates 70.
And, as second opticalthin film 80, can be with any film on the surface that is suitable for protecting this secondplanar substrates 70, for example, antireflective film etc.Preferably, when with 70 combinations of second planar substrates, realize that the film of desirable performance is applied to this second opticalthin film 80.
For example, neutral light intensity light filter can be used as secondplanar substrates 70, and infrared protective film can be used as second optical thin film 80.And ultraviolet protection glass can be used as secondplanar substrates 70, and dim light film and ultraviolet protection film can be used as second opticalthin film 80.
In brief, the combination of secondplanar substrates 70 and second opticalthin film 80 performance that can have according to the glasses display needs, the manufacturing cost of glasses display etc. are suitably selected.
In addition, such as the kind and detailed being described in the list of references of function of the various multilayer film of various light filters, for example Macleod writes " Thin-Filmoptical Filters 3Rd" in the literary composition, so its detailed description here is removed Edition.
In the said structure of first opticalthin film 60, be the refractive index mismatch of regulating between first opticalthin film 60 and the planar substrates 11 (mismatch) why in the reason that single cycle layer group is set on the both sides of many circulation layers group, and regulate refractive index mismatch (that is, each single cycle layer group is a matching layer) between first opticalthin film 60 and second planar substrates 70.This matching layer is used for finely tuning the characteristic of first optical thin film, and the fluctuation of the pairing wavelength coverage of transmittance that for example will reduce reduces.
[the modification example of the tenth embodiment]
The structure of first opticalthin film 60 can be different with said structure.No matter use the sort of structure, all comprise suitable circulation layer group.And, no matter use the sort of structure, wish to be optimized with computing machine.
And, when second opticalthin film 80 and the combination of secondplanar substrates 70, also can use the combination of the little optical glass substrate of chromium (Cr) metallic film etc. and extinction coefficient.
And, as second opticalthin film 80, also can use various function optical thin films, electrochomeric films (EC film) for example, photochromic film (PC film) etc.
Electrochomeric films (EC film) makes the user according to can be selected essential dim light or dim light not by the user mode of user's the glasses display that making operation determined.For example, the user can carry out following selection, for example, be used under the outdoor situation at glasses display by day, when external image is bright especially, reduce light, and be used under the indoor situation at glasses display, when external image when not being very bright, dim light not.
By this operation,, can keep the observability of external image and the observability of display image regardless of the user mode of glasses display.
And, if the use photochromic film, when having only light intensity as exterior light flux L2 very high, this exterior light flux L2 can reduce automatically, make it possible to keep automatically the observability of external image and the observability of display image, and irrelevant with the user mode of glasses display.
Utilize the above-mentioned functions film to improve the function of glasses display significantly.
And in this glasses display, as the 9th embodiment, the dim light ratio of the central area of this image displayoptical system 1 can be easy to be arranged to be higher than the dim light ratio of the neighboring area of image displayoptical system 1.
For example, secondplanar substrates 70 is made by neutral intensity filter, and second opticalthin film 80 is by the dim light thin film fabrication, and the formation district of second optical thin film only limits to the center.
In this glasses display, first opticalthin film 60 can be used the holographic optics thin film fabrication.Optical system shown in Figure 61 is used to make the holographic optics film.But,, be arranged in the light path of two luminous fluxes of Figure 61 with the identical shaped auxiliary prism of these planar substrates because first opticalthin film 60 is clipped between theplanar substrates 11 and secondplanar substrates 70 when using.
And in this glasses display, second opticalthin film 80 can be used the holographic optics thin film fabrication.
[other embodiment]
The dim light function of above-mentioned the 8th embodiment to the ten embodiment (comprising its modification example) can be arranged in any glasses display of first embodiment to the, seven embodiment.