Disclosure of Invention
An object of the present invention is to provide a near-eye display light machine, a near-eye display device and a near-eye display method thereof, which can improve the light energy utilization rate of the image light of the near-eye display light machine.
Another object of the present invention is to provide a near-eye display optical engine, a near-eye display device and a method thereof, which are beneficial to adapt to the current trend of light, thin and miniaturized near-eye display devices.
Another object of the present invention is to provide a near-eye display light machine, a method thereof and a near-eye display device, wherein in an embodiment of the present invention, an included angle between a polarization beam splitting component of the near-eye display light machine and an optical viewing axis ranges from 50 ° to 70 °, which is helpful for improving the overall compactness of the near-eye display light machine.
Another objective of the present invention is to provide a near-eye display light machine, a method thereof and a near-eye display device, wherein in an embodiment of the present invention, the near-eye display light machine uses the characteristics of polarized light to reduce the light energy loss of the image light through reasonable optical design, so as to improve the light energy utilization rate of the image light.
Another object of the present invention is to provide a near-eye display optical engine, a method thereof and a near-eye display device, wherein in an embodiment of the present invention, the near-eye display optical engine can reduce the escape amount of image light, reduce the leakage of the displayed image, and not only facilitate further improvement of the light energy utilization rate of the image light, but also help to protect the privacy of the user.
Another objective of the present invention is to provide a near-eye display light machine, a method thereof and a near-eye display device, wherein in an embodiment of the present invention, an interference prevention unit of the near-eye display light machine adopts a linear polarizer to eliminate an artifact interference caused by an ambient light below, which is helpful to improve a comfortable experience of a user.
Another object of the present invention is to provide a near-eye display optical engine, a method thereof and a near-eye display device, wherein in an embodiment of the present invention, an anti-interference unit of the near-eye display optical engine has a simple structure, low cost and good artifact eliminating effect.
Another object of the present invention is to provide a near-eye display light machine, a method thereof and a near-eye display device, wherein expensive materials or complex structures are not required in the present invention in order to achieve the above-mentioned objects. Accordingly, the present invention successfully and effectively provides a solution that not only provides a near-eye display light engine and method thereof and a near-eye display device, but also increases the practicality and reliability of the near-eye display light engine and method thereof and the near-eye display device.
To achieve at least one of the above or other objects and advantages, the present invention provides a near-eye display optical machine, comprising:
An image source unit for emitting image light along an emission path;
a lens group unit disposed in the emission path of the image source unit for modulating the image light emitted via the image source;
a polarization beam splitting unit, wherein the polarization beam splitting unit is disposed on the emission path of the image source unit, and the lens group unit is disposed between the image source unit and the polarization beam splitting unit, wherein an angle between the polarization beam splitting unit and an optical viewing axis of the near-eye display light machine is greater than 45 °, for reflecting a first polarized image light ray of the image light rays modulated via the lens group unit, and transmitting a second polarized image light ray of the image light rays modulated via the lens group unit;
a perspective reflection unit, wherein the perspective reflection unit is disposed on a reflection side of the polarization beam splitting unit, and the perspective reflection unit corresponds to the optical viewing axis of the near-eye display light machine, and is used for reflecting part or all of the first polarized image light reflected by the polarization beam splitting unit back to the polarization beam splitting unit and allowing part of ambient light to pass through; and
The polarization conversion unit is arranged between the polarization light splitting unit and the perspective reflection unit and is used for converting the first polarized image light into the second polarized image light after passing through the polarization light splitting unit twice so as to be incident into human eyes.
In an embodiment of the invention, an angle between the polarizing beam splitting unit and the optical viewing axis of the near-eye display optical machine is between 50 ° and 70 °.
In one embodiment of the present invention, the polarization splitting unit includes a light transmitting substrate and a polarization splitting film, wherein the polarization splitting film is disposed on a first optical surface of the light transmitting substrate, and the polarization splitting film is disposed between the light transmitting substrate and the image source unit.
In an embodiment of the present invention, a surface shape of the first optical surface of the light-transmitting substrate is a free-form surface.
In an embodiment of the present invention, the perspective reflection unit includes a curved substrate and a portion of the reflection film, wherein the portion of the reflection film is disposed on the second optical surface of the curved substrate, and the portion of the reflection film is located between the curved substrate and the polarization beam splitting unit.
In an embodiment of the present invention, a surface shape of the second optical surface of the curved substrate is a free-form surface.
In an embodiment of the invention, the near-eye display optical engine further includes an anti-interference unit, where the anti-interference unit is located on a side of the polarization beam splitting unit 12 away from the image source unit, and is used for preventing interference light from below from generating visual interference.
In an embodiment of the invention, the anti-interference unit includes a polarization filter element, where the polarization filter element is disposed on a side of the polarization beam splitting unit away from the image source unit, and is configured to absorb a first polarized light and transmit a second polarized light, where a polarization state of the first polarized light and a polarization state of the first polarized image light remain consistent, and a polarization state of the second polarized light and a polarization state of the second polarized image light remain consistent.
In an embodiment of the invention, the polarizing filter element is a linear polarizer.
In an embodiment of the invention, the anti-interference unit further includes a protection substrate and an anti-reflection film, wherein the protection substrate is located at an outer side of the polarized light filter element, so that the polarized light filter element is located between the protection substrate and the polarized light splitting unit, and the anti-reflection film is disposed at an outer surface of the protection substrate.
In an embodiment of the invention, the polarization conversion unit is a 1/4 wave plate.
In an embodiment of the present invention, the lens group unit includes at least one lens, wherein a surface shape of each lens is one of a standard spherical surface, an aspherical surface, a free-form surface, and a diffraction surface.
In an embodiment of the present invention, the image source unit is one of an LCD type, an OLED type, a DLP type, and an LCOS type micro display device.
According to another aspect of the present invention, there is also provided a near-eye display device including:
an apparatus main body; and
at least one of the above near-eye display light machine, wherein the near-eye display light machine is disposed on the device main body to assemble a compact near-eye display device.
According to another aspect of the present invention, the present invention further provides a method for manufacturing a near-eye display optical engine, including the steps of:
setting a lens group unit between an image source unit and a polarization beam splitting unit, wherein the lens group unit and the polarization beam splitting unit are both positioned on an emission path of the image source unit, the lens group unit is used for modulating the image light rays emitted by the image source, and the polarization beam splitting unit is used for reflecting first polarized image light rays in the modulated image light rays and transmitting second polarized image light rays in the modulated image light rays;
Setting a perspective reflection unit on the reflection side of the polarization beam splitting unit to define an optical viewing axis through the perspective reflection unit and the polarization beam splitting unit, wherein an included angle between the polarization beam splitting unit and the optical viewing axis is larger than 45 degrees, and the perspective reflection unit is used for reflecting part or all of the first polarized image light reflected by the polarization beam splitting unit back to the polarization beam splitting unit and allowing part of ambient light to pass through; and
and a polarization conversion unit is arranged between the polarization splitting unit and the perspective reflection unit and is used for converting the first polarized image light into the second polarized image light after passing through the polarization conversion unit twice, so that the second polarized image light is incident into human eyes along the optical viewing axis.
In an embodiment of the invention, the method for manufacturing a near-eye display optical engine further includes the steps of:
an anti-interference unit is arranged on one side, far away from the image source unit, of the polarization light splitting unit, wherein the anti-interference unit comprises a polarization filter element, is used for absorbing first polarized light and transmitting second polarized light, and the polarization state of the first polarized light is kept consistent with that of the first polarized image light; and the polarization state of the second polarized light is consistent with the polarization state of the second polarized image light.
Further objects and advantages of the present invention will become fully apparent from the following description and the accompanying drawings.
These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the appended claims.
Detailed Description
The following description is presented to enable one of ordinary skill in the art to make and use the invention. The preferred embodiments in the following description are by way of example only and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
It will be appreciated by those skilled in the art that in the present disclosure, the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc. refer to an orientation or positional relationship based on that shown in the drawings, which is merely for convenience of description and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore the above terms should not be construed as limiting the present invention.
In the present invention, the terms "a" and "an" in the claims and specification should be understood as "one or more", i.e. in one embodiment the number of one element may be one, while in another embodiment the number of the element may be plural. The terms "a" and "an" are not to be construed as unique or singular, and the term "the" and "the" are not to be construed as limiting the amount of the element unless the amount of the element is specifically indicated as being only one in the disclosure of the present invention.
In the description of the present invention, it should be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, unless explicitly stated or limited otherwise, the terms "connected," "connected," and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through a medium. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.
In recent years, with the rapid development of the augmented reality technology, near-eye display devices capable of realizing augmented reality are increasingly popular and used by people. But is limited by the self-structure of the display light machine in the existing near-eye display device, the light energy utilization rate of the existing display light machine to the image light is extremely low (usually about 12.5%), and the size of the existing display light machine is bigger, so that the quality of the image displayed by the existing display light machine is poor, and the existing display light machine is not in line with the development trend of miniaturization and light thinning of the existing head-mounted display device.
In order to solve the above-mentioned problems, referring to fig. 2 and 3, a first embodiment of the present invention provides a new near-eye display optical engine, which not only can greatly improve the light energy utilization rate of the image light, but also can help to make the structure of the near-eye display optical engine compact. Specifically, as shown in fig. 2, the near-eye display optical machine 10 includes an image source unit 11, a polarization splitting unit 12, a perspective reflection unit 13, a polarization conversion unit 14, and a lens group unit 15.
The image source unit 11 has an emission path 110 for emitting image light 1100 along the emission path 110. The lens group unit 15 is disposed at the emission path 110 of the image source unit 11 for modulating the image light 1100 emitted via the image source unit 11.
The polarization beam splitting unit 12 is arranged in the emission path 110 of the image source 11 for reflecting the first polarized image light 1101 and transmitting the second polarized image light 1102. The polarization splitting unit 12 and the image source unit 11 are located on both sides of the lens group unit 15, respectively (i.e., the lens group unit 15 is located between the polarization splitting unit 12 and the image source unit 11), and an angle θ between the polarization splitting unit 12 and the optical viewing axis 100 of the near-eye display light machine 10 is greater than 45 °, so that the polarization splitting unit 12 is configured to reflect the first polarized image light ray 1101 in the image light ray 1100 modulated via the lens group unit 15, and transmit the second polarized image light ray 1102 in the image light ray 1100 modulated via the lens group unit 15.
The perspective reflection unit 13 is disposed at a reflection side of the polarization beam splitting unit 12, and the perspective reflection unit 13 corresponds to the optical viewing axis 100 of the near-eye display light machine 10, for reflecting a part or all of the first polarized image light 1101 reflected via the polarization beam splitting unit 12 back to the polarization beam splitting unit 12, and allowing a part of ambient light to pass through to propagate to the polarization beam splitting unit 12. The polarization conversion unit 14 is disposed between the polarization beam splitting unit 12 and the perspective reflection unit 13, and is configured to convert the first polarized image light ray 1101 into the second polarized image light ray 1102 after passing through the polarization conversion unit 14 twice.
In this way, the second deflected image light 1102 converted by the polarization conversion unit 14 and the ambient light transmitted through the perspective reflection unit 13 will first transmit through the polarization beam splitting unit 12 and then enter the human eye to be viewed, so that the user can simultaneously see the virtual image corresponding to the image light 1100 and the real image corresponding to the ambient light by means of the near-eye display light machine 10, to realize an augmented reality experience. It can be appreciated that the optical viewing axis 100 of the near-eye display optical engine 10 may be a main viewing axis defined by the polarization splitting unit 12 and the perspective reflecting unit 13, so that a user can see both the image light emitted by the image source unit 11 and the external ambient light along the optical viewing axis 100, so as to obtain an augmented reality experience of virtual-real fusion. It will be appreciated that the perspective reflecting unit 13 may be adjusted for optimal position according to the specific system design.
In other words, the second deflected image light 1102 converted by the polarization conversion unit 14 can pass through the polarization beam splitting unit 12, and is not lost due to the reflection of the polarization beam splitting unit 12, so that the light energy utilization rate of the image light by the near-eye display light engine 10 is improved. For example, when the perspective reflection unit 13 of the near-eye display light machine 10 is a partial mirror (i.e. reflects 50% of the light and transmits 50% of the light), the image light is only half lost when reaching the polarization splitting unit 12 for the first time and passing through the perspective reflection unit 13, i.e. the light energy utilization rate of the near-eye display light machine 10 for the image light reaches 25%, which is doubled compared with the light energy utilization rate of the existing display light machine 10P for the image light. Meanwhile, since the included angle θ between the polarization beam splitting unit 12 and the optical viewing axis 100 of the near-eye display optical engine 10 is greater than 45 °, the eye-release (i.e. the eye point distance, such as the distance from the lens to the forehead) of the near-eye display optical engine 10 is increased, so that the adapter is added for a near-sighted or far-sighted user, and the experience and comfort of wearing by the user are improved. In addition, this configuration also facilitates the design adjustment of the whole system, so that the near-eye display optical engine 10 is more compact than the existing optical engine, and is suitable for meeting the current trend of miniaturization and light and thin.
Preferably, as shown in FIG. 3, the angle θ between the polarization beam splitting unit 12 and the optical viewing axis 100 of the near-eye display light engine 10 is between 50 ° and 70 °, i.e., 50+.θ+.ltoreq.70°.
It is noted that in the present invention, the first polarized image light ray 1101 may be implemented as polarized light having a first polarization state, and the second polarized image light ray 1102 may be implemented as polarized light having a second polarization state, wherein the polarization direction of the first polarized image light ray 1101 is preferably perpendicular to the polarization direction of the second polarized image light ray 1102. For example, the first polarized image light 1101 may be implemented as, but not limited to, S polarized light or P polarized light, and the second polarized image light 1102 may be implemented as, but not limited to, P polarized light or S polarized light, respectively.
Furthermore, in this first embodiment of the present invention, as shown in fig. 2 and 3, the polarization conversion unit 14 may be implemented as, but is not limited to, a first 1/4 wave plate 141 for converting the first or second polarized image light ray 1101, 1102 passing twice through the 1/4 wave plate 141 into the second or first polarized image light ray 1102, 1101. That is, the first 1/4 wave plate 141 is disposed between the polarization beam splitting unit 12 and the perspective reflection unit 13, so that the first polarized image light 1101 reflected by the polarization beam splitting unit 12 passes through the first 1/4 wave plate 141 for the first time to be converted into a first circular polarized light, passes through the first 1/4 wave plate 141 for the second time to be converted into the second polarized image light 1102 after being reflected by the perspective reflection unit 13 for the second circular polarized light, and the first polarized image light 1101 passes through the 1/4 wave plate 141 for the second time to be converted into the second polarized image light 1102, so that a majority of the reflected image light can pass through the polarization beam splitting unit 12 to be incident to human eyes, which helps to improve the light energy utilization rate of the near-eye display light machine 10 on the image light.
It should be noted that, as shown in fig. 3, the polarization splitting unit 12 of the near-eye display light engine 10 of the first embodiment of the present invention may include a light-transmitting substrate 121 and a polarization splitting film 122, where the light-transmitting substrate 121 has a first optical surface 120, and the first optical surface 120 of the light-transmitting substrate 121 faces the image source unit 11 (i.e., the first optical surface 120 is an upper surface of the light-transmitting substrate 121), and the polarization splitting film 122 is disposed on the first optical surface 120 of the light-transmitting substrate 121, so that the polarization splitting film 122 is located between the light-transmitting substrate 121 and the image source unit 11 and is used for reflecting the first polarized image light 1101 in the image light 1100.
In particular, the polarization splitting film 122 may be, but is not limited to, attached to or plated on the first optical surface 120 of the light transmissive substrate 121. It is understood that the light-transmitting substrate 121 may be, but is not limited to, made of a light-transmitting material such as optical plastic or optical glass, etc., to ensure that light can pass through the light-transmitting substrate 121.
Preferably, the surface shape of the first optical surface 120 of the light-transmitting substrate 121 of the polarizing beam-splitting unit 12 may be, but is not limited to, implemented as a free-form surface, so that image light or ambient light can be shaped when reflected or transmitted at the polarizing beam-splitting unit 12, which helps to improve the imaging quality of the near-eye display light machine 10.
Also, as shown in fig. 3, the perspective reflection unit 13 of the near-eye display light engine 10 according to the first embodiment of the present invention may include a curved substrate 131 and a part of reflection film 132, wherein the curved substrate 131 has a second optical surface 130, and the second optical surface 130 of the curved substrate 131 faces the polarization splitting unit 12 (i.e., the second optical surface 130 is an inner surface of the curved substrate 131), and the part of reflection film 132 is disposed on the second optical surface 130 of the curved substrate 131, such that the part of reflection film 132 is located between the polarization splitting unit 12 and the curved substrate 131, for reflecting the first polarized image light 1101 such that the first polarized image light 1101 passes through the first 1/4 wave plate 141 twice to be converted into the second polarized image light 1102.
In particular, the partially reflective film 132 may be, but is not limited to, attached to or plated on the second optical surface 130 of the curved substrate 131. It will be appreciated that the curved substrate 131 may be made of a light-transmitting material such as optical plastic or optical glass, etc. to ensure that ambient light can pass through the see-through reflecting unit 13.
Preferably, the surface shape of the second optical surface 130 of the curved substrate 131 of the perspective reflection unit 13 may be implemented as a free curved surface, so that image light and ambient light can be shaped when reflected or transmitted at the second optical surface 130 of the perspective reflection unit 13.
It should be noted that, in other examples of the present invention, the first optical surface 130 of the curved substrate 131 may also face the opposite direction of the polarizing beam splitting unit 12 (i.e., the second optical surface 130 is the outer surface of the curved substrate 131), so that the curved substrate 131 is located between the partially reflective film 132 and the polarizing beam splitting unit 12, and thus the image light will first pass through the curved substrate 131 and then be emitted by the partially reflective film 132 to pass through the curved substrate 131 again to reach the polarizing beam splitting unit 12.
According to the above-described first embodiment of the present invention, as shown in fig. 2 and 3, the lens group unit 15 of the near-eye display light engine 10 may include, but is not limited to, at least one lens 151, wherein the surface shape of each lens 151 may be implemented, but is not limited to, such as a standard spherical surface, an aspherical surface, a free-form surface, or a diffraction surface, for modulation shaping of the image light 1100 from the image source unit 11. In other words, the surface shape of the at least one lens 151 may be, but is not limited to, one or more selected from the group consisting of a standard spherical surface, an aspherical surface, a free-form surface, and a diffraction surface. It is to be understood that the freeform surface referred to in the present invention may be implemented as, but is not limited to, an XY polynomial freeform surface, a Zernike polynomial freeform surface, or a toric surface, among others.
It should be noted that, in the above-described first embodiment of the present invention, the image source unit 11 may be, but is not limited to, implemented as one of LCD, OLED, DLP, LCOS type micro display devices for providing the image light 1100. In particular, when the image source unit 11 is implemented as an LCOS-type micro display device, the LCOS-type micro display device can emit image light having a specific polarization state so as to cooperate with the polarization splitting unit 12, so that the image light emitted by the image source unit 11 does not generate loss at the polarization splitting unit 12, which is helpful for further improving the light energy utilization rate of the near-eye display light machine 10 for the image light.
It can be appreciated that the image source unit 11 of the near-eye display light machine 10 is implemented as an LCOS micro display device, and is configured to emit the first polarized image light beam 1101 along the emission path 110, so that a substantial portion of the first polarized image light beam 1101 emitted by the LCOS micro display device is reflected by the polarizing beam splitter unit 12 to the perspective reflection unit 13, and is not lost due to the light passing through the polarizing beam splitter unit 12, so that the light energy utilization rate of the near-eye display light machine 10 on the image light beam is greatly improved. In other words, the image light is only lost due to transmission at the perspective reflection unit 13, and is not lost due to reflection or transmission at the polarization beam splitting unit 12, so that the light energy utilization rate of the image light by the near-eye display light machine 10 is close to 50%.
However, since the image light is transmitted at the perspective reflection unit 13, that is, the image light escapes from the front of the near-eye display optical engine 10, this not only causes a light energy loss of the image light, but also makes the light energy utilization rate of the image light by the near-eye display optical engine 10 lower, and cannot provide a high quality image; but also to enable others to see the image being viewed by the user from outside the near-eye display engine 10, without protecting the privacy of the user.
Therefore, in order to solve these problems, some embodiments of the present application provide a near-eye display light machine, in which the image source unit of the near-eye display light machine is configured to emit image light having a predetermined spectrum, and the perspective reflection unit of the near-eye display light machine includes a reflection film system configured to reflect the predetermined spectrum, so that escape of image light from a front portion of the near-eye display light machine can be greatly reduced, so that an image displayed by the near-eye display light machine cannot be seen by the outside, thereby achieving the purposes of improving light energy utilization and protecting privacy.
It should be noted that, in these embodiments of the present application, the detailed description and various modifications of the perspective reflection unit of the near-eye display optical machine may refer to the chinese patent application No. 201811523682.9, entitled "a display optical machine and its manufacturing method, and a near-eye display device" filed by the inventor, and the disclosure of the present application is omitted herein.
It should be noted that, limited to the self-structure of the near-eye display light machine 10 according to the first embodiment of the present invention, the ambient light (hereinafter referred to as the disturbing light) under the near-eye display light machine 10 will be inevitably reflected into the human eye by the polarization beam splitting unit 12, so that the user can view the scene in front of the near-eye display light machine 10 and also view the virtual image of the object under the near-eye display light machine 10, thereby causing visual disturbance (i.e. artifact disturbance). Therefore, in order to solve the above-mentioned problems, as shown in fig. 4 and 5, a second embodiment of the present invention provides a near-to-eye display optical machine 10A, which can effectively prevent the interference light below from being reflected into the eyes of the user, so as to prevent the occurrence of visual interference. Specifically, as shown in fig. 4, compared to the above-described first embodiment of the present invention, the near-eye display light machine 10A according to the second embodiment of the present invention is different in that: the near-eye display light machine 10A further includes an anti-interference unit 16A, wherein the anti-interference unit 16A is located on a side of the polarization beam splitting unit 12 away from the image source unit 11, for preventing the interference light 100A from the lower side of the near-eye display light machine 10A from generating visual interference.
More specifically, as shown in fig. 4 and 5, the interference preventing unit 16A includes a polarization filter 161A, wherein the polarization filter 161A is disposed on the side of the polarization beam splitting unit 12 away from the image source unit 11, for absorbing the first polarized light 101A and transmitting the second polarized light 102A, wherein the first polarized light 101A is implemented as polarized light having the first polarization state, and the second polarized light 102A is implemented as polarized light having the second polarization state. In other words, in the present invention, the polarization state of the first polarized light 101A is kept identical to the polarization state of the first polarized image light 1101; and the polarization state of the second polarized light 102A is consistent with the polarization state of the second polarized image light 1102 (e.g., the first polarized light 101A and the first polarized image light 1101 have the same polarization state, and the second polarized light 102A and the second polarized image light 1102 have the same polarization state). For example, in an example of the present invention, the first polarized light 101A and the first polarized image light 1101 are each implemented as polarized light having an S polarization state (S polarized light for short); the second polarized light 102A and the second polarized image light 1102 are both implemented as polarized light having a P-polarization state (P-polarized light for short).
Therefore, when the disturbance light from below the near-eye display light machine 10A passes through the polarization filter element 161A of the disturbance prevention unit 16A, first, a first polarized light 101A in the disturbance light 100A is absorbed by the polarization filter element 161A and a second polarized light 102A in the disturbance light 100A is transmitted, so that the disturbance light 100A is filtered from unpolarized light into the second polarized light 102A; next, the second polarized light 102A transmitted through the polarizing filter 161A propagates upward to the polarizing beam splitter 12, so as to escape through the polarizing beam splitter 12 without being reflected into the human eye, thereby achieving the purpose of preventing the interference light 100A from being visually interfered under the near-eye display light machine 10A.
It will be appreciated that since the polarization beam splitter unit 12 is configured to reflect polarized light having a first polarization state and transmit polarized light having a second polarization state, the second polarized light 102A transmitted through the polarization filter element 161A is transmitted through the polarization beam splitter unit 12 only and is not reflected by the polarization beam splitter unit 12. In addition, since the polarizing filter element 161A allows the second polarized light 102A to pass through, that is, allows the polarized light with the second polarization state to pass through, the image light and the ambient light propagating along the optical viewing axis must pass through the polarizing filter element 161A to propagate into the human eye after passing through the polarizing beam splitting unit 12, so that the anti-interference unit 16A does not affect the original effects (such as image contrast, light energy utilization rate, etc.) of the near-eye display optical machine 10A while playing an artifact eliminating role, and is helpful for greatly improving the comfort experience of the user.
Illustratively, in this embodiment of the invention, the polarizing filter element 161A may be implemented as, but is not limited to, a linear polarizer for allowing only light of the second polarization to pass therethrough and absorbing light of the first polarization. Preferably, the polarization filter element 161A is implemented as a P-polarizing plate for allowing only P-polarized light to pass therethrough and absorbing S-polarized light so as to match the polarizing beam-splitting film (e.g., PBS film, reflecting S-polarized light, and transmitting P-polarized light) in the polarizing beam-splitting unit 12.
Further, as shown in fig. 5, the interference prevention unit 16A may further include a protection substrate 162A, wherein the protection substrate 162A is positioned outside the polarization filter element 161A such that the polarization filter element 161A is positioned between the protection substrate 162A and the polarization splitting unit 12 to protect and support the polarization filter element 161A by the protection substrate 162A. It is understood that the protective substrate 162A may be, but is not limited to, made of a light-transmitting material such as glass, transparent plastic, etc., to allow light to pass through the protective substrate 162A.
Preferably, as shown in fig. 5, the anti-interference unit 16A may further include an anti-reflection film 163A, where the anti-reflection film 163A is disposed on the outer surface of the protection substrate 162A, so as to reduce the reflection of the interference light 100A on the outer surface of the protection substrate 162A, and help to avoid causing visual interference. It is understood that the anti-reflection film 163A may be, but is not limited to being, plated on the outer surface of the protective substrate 162A. For example, in other examples of the present invention, the anti-reflection film 163A may be directly attached to the outer surface of the protective substrate 162A.
It should be noted that, in the second embodiment of the present invention, other structures of the near-eye display light engine 10A are the same as those of the near-eye display light engine 10 according to the first embodiment of the present invention except for the above-mentioned structures, and the near-eye display light engine 10A also has various modification embodiments similar to or the same as those of the near-eye display light engine 10 according to the first embodiment, which will not be repeated herein.
According to another aspect of the invention, the invention further provides a near-eye display device configured with a near-eye display light engine. As shown in fig. 6, the near-eye display device 1 may include at least one near-eye display optical machine 10 (10A) and a device main body 20, where the near-eye display optical machine 10 (10A) is disposed on the device main body 20 to assemble the near-eye display device 1 with a compact structure, so that the near-eye display device is small in size and light in weight, and is helpful for meeting the current development trend of miniaturization and light-weight.
It is noted that the device body 20 may be implemented as, but is not limited to, an eye glass body, so that the near-eye display device 1 is implemented as AR glasses, which helps to enhance the user's use experience. It will be appreciated that in other examples of the invention, the near-eye display device 1 may also be implemented as other types of AR devices, such as AR helmets and the like.
According to another aspect of the present invention, the present invention further provides a method for manufacturing a near-eye display light machine. Specifically, as shown in fig. 7, the method for manufacturing the near-eye display optical engine 10 includes the steps of:
s310: disposing a lens group unit 15 between an image source unit 11 and a polarization splitting unit 12, and the lens group unit 15 and the polarization splitting unit 12 being located in an emission path of the image source unit 11, wherein the lens group unit 15 is configured to modulate the image light 1100 emitted via the image source 11, and wherein the polarization splitting unit 12 is configured to reflect a first polarized image light 1101 in the modulated image light 1100 and transmit a second polarized image light 1102 in the modulated image light 1100;
s320: providing a perspective reflection unit 13 on a reflection side of the polarization beam splitting unit 12 to define an optical viewing axis 100 through the perspective reflection unit 13 and the polarization beam splitting unit 12, wherein an angle between the polarization beam splitting unit 12 and the optical viewing axis 100 is greater than 45 °, wherein the perspective reflection unit 13 is configured to reflect a part or all of the first polarized image light 1101 reflected by the polarization beam splitting unit 12 back to the polarization beam splitting unit 12, and allow a part of ambient light to transmit through to propagate to the polarization beam splitting unit 12; and
S330: a polarization conversion unit 14 is disposed between the polarization splitting unit 12 and the perspective reflecting unit 13, so that the first polarized image light 1101 is converted into the second polarized image light 1102 after passing through the polarization conversion unit 14 twice, and then is incident into the human eye along the optical viewing axis 100 to be viewed.
It can be understood that the order among the step S310, the step S320, and the step S330 is not sequential in the manufacturing method of the near-eye display optical engine 10 of the present invention.
It is noted that, in an example of the present invention, the polarization splitting unit 12 includes a light transmissive substrate 121 and a polarization splitting film 122, wherein the polarization splitting film 122 is disposed on the first optical surface 120 of the light transmissive substrate 121, and the polarization splitting film 122 is located between the light transmissive substrate 121 and the image source unit 11.
In an example of the present invention, a surface shape of the first optical surface of the light-transmitting substrate is a free-form surface.
In an example of the present invention, the perspective reflection unit 13 includes a curved substrate 131 and a part of reflection film 132, wherein the part of reflection film 132 is disposed on the second optical surface 130 of the curved substrate 131, and is used for reflecting the first polarized image light 1101 so that the first polarized image light 1101 passes through the first 1/4 wave plate 141 twice and is converted into the second polarized image light 1102.
In one example of the present invention, the second optical surface of the curved substrate has a surface shape of a free-form surface.
It should be noted that, as shown in fig. 7, the method for manufacturing the near-eye display optical engine 10 may further include the steps of:
s340: disposing an anti-interference unit 16A on a side of the polarization beam splitter unit 12 away from the image source unit 11, wherein the anti-interference unit 16A includes a polarization filter 161A for absorbing the first polarized light 101A and transmitting the second polarized light 102A, and the polarization state of the first polarized light 101A is consistent with the polarization state of the first polarized image light 1101; and the polarization state of the second polarized light 102A remains consistent with the polarization state of the second polarized image light 1102.
It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are by way of example only and are not limiting. The objects of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been shown and described in the examples and embodiments of the invention may be modified or practiced without departing from the principles described.