CN101767511B - Optical anti-counterfeiting component and product with anti-counterfeiting component - Google Patents

Abstract

The invention provides an optical anti-counterfeiting component, which comprises a substrate, a harmonic diffractive micro lens array and a micro graphics-context array. The substrate is provided with a first surface and a second surface; the harmonic diffractive micro lens array is arranged on the first surface of the substrate; and the micro graphics-context array is arranged on the second surface of the substrate. The substrate is transparent at least locally, and is set to be thick enough to make the micro graphics-context array being arranged near the focal plane of the harmonic diffractive micro lens array. The pattern with dynamic effects such as focusing depth changes or position changes can be formed due to the Moore amplification of the micro graphics-context array through the harmonic diffractive micro lens array. The invention can guarantee the security of banknotes, credit cards, passports, negotiable securities, other high-security products and other products with high added values, and the products can be applied in such forms as security lines, anti-counterfeiting marks, wide bars, transparent windows and the like.

Description

Optical anti-counterfeiting element and have the product of this Security element

Technical field

The application relates to the optical anti-counterfeiting technology, more specifically, relates to optical anti-counterfeiting element that adopts microlens array and the product that has this Security element.

Background technology

The optical anti-counterfeiting element is widely used in the products such as banknote, credit card, passport and securities.At present, in the optical anti-counterfeiting element that adopts microlens array, use refraction at spherical surface type lenticule and fresnel diffraction type lenticule usually.In this microlens array optical anti-counterfeiting element, little picture and text array layer places near focal plane or its of microlens array, More's amplification of little picture and text array is realized the pattern that has certain depth of field and present peculiar dynamic effect through microlens array.

In the application of securities such as for example banknote,, therefore lenticular focal length had restriction because the thickness of Security element is had restriction.For example, when the thickness of Security element is restricted to when being less than or equal to 50 μ m, lenticular focal length is restricted to equally and is less than or equal to 50 μ m.Yet; In order to obtain corresponding little focal length, no matter be refraction at spherical surface type lenticule or fresnel diffraction type lenticule, (for example all need the diameter of lenticule unit be reduced in the certain limit; Be less than or equal to 50 μ m), the arrangement cycle of array also reduces accordingly.Because this Security element equals the ratio of the arrangement periodic inequality between cycle and lens arra and the little literal array to little picture and text enlargement factor; The subtle change of arranging periodic inequality can cause the variation of very big enlargement ratio; Therefore; Cause that accuracy requirement significantly improves in master processing and the follow-up batch duplicating of microlens array the little arrangement cycle, increased manufacture difficulty.

Therefore, expectation provides a kind of microlens array optical anti-counterfeiting element, can make lenticule when keeping little focal length, have bigger diameter and arrangement cycle, thereby under satisfying the situation of thickness limits, reduce the accuracy requirement in the manufacturing process.

Summary of the invention

Optical anti-counterfeiting element according to an embodiment of the application comprises: basic unit has the first surface and the second surface that are parallel to each other; Humorous diffraction microlens array is positioned at the said first surface of said basic unit; And little picture and text array, be positioned at the said second surface of said basic unit.Wherein, said basic unit is local at least transparent, and its thickness is provided so that said little picture and text array is positioned near the focal plane of said humorous diffraction microlens array.

Optical anti-counterfeiting element according to another embodiment of the application comprises basic unit, comprises the first and the second portion of space certain distance; Be arranged at the humorous diffraction microlens array of said first; And the little picture and text array that is arranged at said second portion; Wherein, The said first of said basic unit and said second portion are local at least transparent; And the thickness of said basic unit is set to when through folding when said first is overlapped with said second portion, and said little picture and text array is positioned near the focal plane of said humorous diffraction microlens array.

In addition, the application also provides the product that comprises above-mentioned optical anti-counterfeiting element.

Description of drawings

Fig. 1 a is the schematic cross-section that uses the optical anti-counterfeiting element of the humorous diffraction microlens array of continuous type according to the application's a embodiment;

Fig. 1 b, Fig. 1 c show a kind of arrangement mode according to humorous diffraction microlens array and little picture and text array in the application's the optical anti-counterfeiting element;

Fig. 1 d, Fig. 1 e show the another kind of arrangement mode according to humorous diffraction microlens array and little picture and text array in the application's the optical anti-counterfeiting element;

Fig. 1 f shows the embodiment of not at the same level time humorous diffraction microlens;

Fig. 2 is the schematic cross-section that uses the optical anti-counterfeiting element of the humorous diffraction microlens array of notch cuttype according to the application's a embodiment;

Fig. 3 is the schematic cross-section that uses the optical anti-counterfeiting element of the humorous diffraction microlens array of reflection-type according to the application's a embodiment;

Fig. 4 is for comprising the schematic cross-section of the optical anti-counterfeiting element of protective clear layer according to the application's a embodiment;

Fig. 5 is for comprising the schematic cross-section of the optical anti-counterfeiting element of liquid crystal layer according to the application's a embodiment;

Fig. 6 a is the synoptic diagram according to the optical anti-counterfeiting element of the humorous diffraction microlens array of the apart of the application's an embodiment employing and little picture and text array; And

Fig. 6 b be shown in Fig. 6 a according to the synoptic diagram when the humorous diffraction microlens array of apart and little picture and text array overlap in the application's the embodiment.

Embodiment

According to the application's embodiment, adopt humorous diffraction microlens array to realize optical anti-counterfeiting.

Humorous diffraction microlens is the optical device according to humorous diffraction optics (being also referred to as the high order diffraction optics) design.Its principle is that the senior inferior of 2 π of getting phase place designs diffraction element, makes a plurality of wavelength in the whole wave band have identical focal power.In humorous diffraction microlens, the optical path difference between endless belt is p a times of design wavelength, and wherein, p is greater than 1.As a kind of special case, when the order of diffraction time p equals 1, be the diffractive designs of routine.

The illustrative embodiments of DETAILED DESCRIPTION The present application below with reference to accompanying drawings.

Fig. 1 a shows the schematic cross-section according to the opticalanti-counterfeiting element 1 of the application's a illustrative embodiments.Shown in Fig. 1 a, opticalanti-counterfeiting element 1 comprises the humorousdiffraction microlens array 3 and little picture andtext array 4 ofbasic unit 2 and two opposed surface that lay respectively at basic unit 2.The thickness ofbasic unit 2 is provided so that little picture andtext array 4 is positioned near the focal plane of humorousdiffraction microlens array 3.

Basic unit 2 is local at least transparent colourless or coloured media layers.It can be the single transparent dielectric film of one deck, and for example PET film, PVC film etc. also can be the transparent dielectric films that the surface has functional coating (such as embossed layer), can also be the multilayer film through being composited.

Humorousdiffraction microlens array 3 is made up of a plurality of humorous diffraction microlens of periodic arrangement, and can for example be formed at a surface ofbasic unit 2 through the UV mould pressing process.Its working depth for example can be preferably 0.5 μ m to 8 μ m less than 15 μ m.

Little picture andtext array 4 is made up of a plurality of little picture and text unit of periodic arrangement.The little picture and text unit in little picture andtext array 4 and the position of the humorous diffraction lens in the humorousdiffraction microlens array 3 are complementary.Little picture andtext array 4 can be formed at another surface of basic unit through contour forging, printing, ink-jet, impression, laser ablation, dyeing, photochromic, partially metallised or UV mode such as duplicate.Little picture andtext array 4 and background thereof also can be made up of the micro-nano structure of different structure.Different micro-nano structures can produce different optical effects, becomes effect etc. such as antireflection, color selection, light.Little picture andtext array 4 and background thereof can be monochromatic, polychrome or colored.

Although show two opposed surface that humorousdiffraction microlens array 3 and little picture andtext array 4 lay respectively atbasic unit 2 at Fig. 1 a; But; Humorousdiffraction microlens array 3 also can be respectively formed on two different films with little picture andtext array 4, and then through combination process as known in the art the two is combined with each other.The two membranes compound tense; The film that has a humorousdiffraction microlens array 3 of continuous type can be back-to-back compound with the film that has little picture andtext array 4, and promptly the distance between the humorousdiffraction microlens array 3 of continuous type and the little picture andtext array 4 is the thickness that the thickness of two membranes adds compound adhesive; Also can be that the film that has a humorousdiffraction microlens array 3 of continuous type is compound to same direction with the pellicular front that has little picture andtext array 4, promptly the distance between the humorousdiffraction microlens array 3 of continuous type and the little picture andtext array 4 adds the thickness of compound adhesive for the thickness of a skim wherein.

In addition, humorousdiffraction microlens array 3 also can form with any suitable arrangement with little picture andtext array 4 as required.Although the application is example with the periodic arrangement the application's embodiment is described; But should be appreciated that; Arrangement non-periodic, symmetric offset spread, asymmetric geometry, random alignment etc. other arbitrarily arrangement mode all be fine, as long as the arrangement mode of microlens array and the arrangement mode of little picture and text array are complementary.For example; Fig. 1 b and Fig. 1 c show a kind of arrangement mode of the humorousdiffraction microlens array 3 of continuous type and corresponding with it little picture andtext array 4, and Fig. 1 d and Fig. 1 e show the another kind of arrangement mode of the humorousdiffraction microlens array 3 of continuous type and corresponding with it little picture andtext array 4.

Should be appreciated that; Although the humorousdiffraction microlens array 3 of the continuous type that is made up of the humorous diffraction microlens of continuous type has been shown in the embodiment shown in Fig. 1 a-1e; But the microlens array that in other embodiments, also can adopt the humorous diffraction microlens by other type to constitute.For example, in embodiment shown in Figure 2, adopted the notchcuttype microlens array 5 that constitutes by the humorous diffraction microlens of notch cuttype.

The focal length of the humorousdiffraction microlens array 3 that uses according to the application's opticalanti-counterfeiting element 1 is 5 μ m to 100 μ m, and is preferably 10 μ m to 30 μ m.The arrangement cycle of humorous diffraction microlens is 20 μ m to 200 μ m in the humorousdiffraction microlens array 3, and is preferably 50 μ m to 100 μ m.In little picture andtext array 4 in the arrangement cycle of little picture and text unit and the humorousdiffraction microlens array 3 the arrangement cycle of humorous diffraction microlens be complementary.According to reproducing effect of requirement, the arrangement cycle of little picture and text unit can equal, is slightly larger than or is slightly less than the arrangement cycle of humorous diffraction microlens.When seeing through the humorousdiffraction microlens array 3 shown in Fig. 1 a and observe, can see amplification, certain depth of field is arranged and presents the picture and text of peculiar dynamic effect.Relation between the parameter of reproduction effect andmicrolens array 3 and little picture andtext array 4 can be consulted the detailed argumentation among one Chinese patent application 200480040733.2 and the open US2009/0034082 of United States Patent (USP).

Fig. 1 f shows the example of not at the same level time humorous diffraction microlens.Inferior for level is the humorous diffraction microlens of p, and its center thickness is that p λ/(n-1), wherein, n is the refractive index of lens, and λ is a vacuum wavelength.It is thus clear that the center thickness of humorous diffraction microlens is directly proportional with level time p.

For example, be the conventional diffraction lens of 25 μ m, design wavelength 550nm for focal length, center thickness can be 1.1 μ m, and the diameter of lens can be 22 μ m; And be similarly the humorous diffraction lens of the level time p=3 of 25 μ m for focal length, and under same horizontal machining precision (endless belt that is ragged edge has identical size), center thickness is 3.3 μ m, lens diameter is 36 μ m.The blaze wavelength of this humorous diffraction lens is 550nm, is the highstrung yellow-green light of human eye.Therefore, when using this humorous diffraction lens, need the color of little picture and text correspondingly be designed to yellow green.Similarly, for the humorous diffraction lens of p=5, under same horizontal machining precision, center thickness is 5.5 μ m, and lens diameter is 52 μ m.The blaze wavelength of this humorous diffraction lens is 458,550,687nm, corresponding to bluish violet, yellowish green and red light.In this case, need the color of little picture and text correspondingly be designed to bluish violet, yellowish green and/or red.

Because humorous diffraction microlens array only glitters to specific one or several wavelength, differ and other wavelength produced, therefore, be chosen as correspondingly through color with lenticular blaze wavelength with little picture and text, can reach false proof requirement.Visible from above explanation, keeping under the constant situation of focal length, the humorous diffraction microlens that can select to have larger diameter replaces conventional diffraction lens, thereby has reduced the dimension precision requirement in the manufacture process and reduced manufacture difficulty.

According to the application's embodiment, for humorous diffraction microlens, can have the material of appropriate index and suitable level time p according to concrete application choice, thereby optimize the diameter and the center thickness of lens, keep the focal length of lens constant simultaneously.According to the application's embodiment, can the level of humorous diffraction microlens time be chosen as 1 to 15, preferably, be 3 to 7.

The order of diffraction that the working depth of humorous diffraction microlens array designs except receiving time influences, also with to form lenticular material refractive index relevant.For example, humorous diffraction microlens array can adopt the high refractive index polymer nano composite material to process, thereby reduces lenticule thickness.According to the application's embodiment, can the thickness of humorous diffraction microlens be chosen as at 0.3 μ m in the scope of 15 μ m, preferably, at 0.5 μ m in the scope of 8 μ m.

Fig. 2 shows the schematic cross-section that uses the opticalanti-counterfeiting element 1 of the humorousdiffraction microlens array 5 of notch cuttype according to the application, wherein, has replaced the humorousdiffraction microlens array 3 of continuous type among Fig. 1 a with the humorousdiffraction microlens array 5 of notch cuttype.The humorous diffraction microlens that modern mask-making technology is made notch cuttype is more prone to than the humorous diffraction microlens of making continuous type, and the production reproduction process is identical, i.e. mold pressing production technology.The exponent number of ladder is high more, and the humorousdiffraction microlens array 5 of notch cuttype is approaching more with the performance of the humorousdiffraction microlens array 3 of continuous type, can require to confirm the exponent number of ladder according to reality.

In above-described embodiment, the humorous diffraction microlens of employing all is the humorous diffraction lens of transmission-type.Yet, can also adopt the humorous diffraction microlens of the reflection-type that has the reflection horizon according to the application's optical anti-counterfeiting element.

Fig. 3 shows the schematic cross-section that uses the opticalanti-counterfeiting element 1 of the humorousdiffraction microlens array 6 of reflection-type according to the application.In embodiment shown in Figure 3, scribble or be coated with one or morelayers reflection horizon 7 on the surface of humorous diffraction microlens array 6.Reflection horizon 7 can be metallic reflector, dieletric reflection layer or its combination.Metallic reflector for example can adopt aluminium, gold, silver, chromium, zinc or be alloy.Dielectric film for example can adopt MgF₂, LiF, SiO₂, Al₂O₃, TiO₂, ZnS, Si₃N₄Bragg catoptron Deng material formation.The humorous diffraction microlens that uses in the humorousdiffraction microlens array 6 of reflection-type can be that continuous type also can be step-like.

When observing, the plane at humorousdiffraction microlens array 6 places is positioned at the position away from human eye, and the plane at little picture andtext array 4 places is between the harmoniousdiffraction microlens array 6 of human eye.Because identical humorous diffraction microlens is applying the reflection horizon when using as the reflection-type lens, the focal length when its focal length is significantly less than as the transmission-type lens, therefore, the humorous diffraction microlens of use reflection-type can reduce the center thickness of lens significantly.

According to the application's embodiment, opticalanti-counterfeiting element 1 can also have one or more functional layers, for example, and protective seam, liquid crystal layer and/or tack coat etc.For example, microlens array layer upper surface, microlens array layer lower surface, film, little picture and text upper surface, little picture and text layer and little picture and text lower surface all can add the functional layer of not amplified by microlens array.

Fig. 4 shows the opticalanti-counterfeiting element 1 according to an embodiment of the application, and it further comprises the protectiveclear layer 8 that is positioned on the humorous diffraction microlens array 3.In this embodiment, in order to protect humorous diffraction microlens array and the serviceable life that increasesSecurity element 1, at one or two surface coated, one or more layers protectiveclear layer 8 of landfill formation of Security element 1.When protectiveclear layer 8 directly contacted with humorousdiffraction microlens array 3, the refractive index of protectiveclear layer 8 was less than the refractive index of microlens array, and refractive index difference is not less than 0.3.

Fig. 5 shows the opticalanti-counterfeiting element 1 according to an embodiment of the application, and it comprises that further the liquid crystal light that is positioned on the humorousdiffraction microlens array 3 becomes layer 9.Liquid crystal light becomeslayer 9 can be used in any one Security element in the corresponding scheme of Fig. 1 to Fig. 4,, can liquid crystal light be become one or two surface that material is coated on above-mentioned any Security element that is.In addition, can also liquid crystal light be become material and be coated betweenbasic unit 2 and the transmission-type lenticule 3, perhaps betweenbasic unit 2 and the reflection-type lenticule 7.Liquid crystal layer 9 can cover the part or all of of its coating surface.

In addition, also can on one or two surface ofSecurity element 1, be coated with tack coat, so that can bond together with protected object.Particularly, can adhesive glue be coated one or two surface of above-mentioned any Security element.Tack coat covers the part or all of of its coating surface.When tack coat directly contacted with humorous diffraction microlens, the refractive index of tack coat was less than the refractive index of microlens array, and refractive index difference is not less than 0.3.

In above-mentioned all embodiments, can further have diffraction light change characteristic, interference light change characteristic, micro-nano structure characteristic, print characteristics, partially metallised characteristic, fluorescent characteristics between the surface ofSecurity element 1 and each intermediate interface or the interface and be used for machine-readable magnetic characteristic etc.

The application is particularly suitable for being made into safety line.The thickness of safety line is not more than 50 μ m, can be used for the false proof of all kinds of high safety products such as banknote, passport, securities.

The application also can be used as label, sign, wide, transparent window etc., can stick on the various article through various bonding mechanisms, for example transfers on high safety products such as banknote, credit card and the high value added product.

Have the product of the application's optical anti-counterfeiting element, include but not limited to all kinds of high safety products and high value added products such as banknote, credit card, passport, securities, and each wrapping paper, packing box etc.

As a special embodiment, humorous diffraction microlens array and little picture and text array can be separately positioned in the first and second portion of basic unit.First and second portion are local at least transparent, and the thickness of basic unit is provided so that when said first overlaps with said second portion said little picture and text array is positioned near the focal plane of said humorous diffraction microlens array.Fig. 6 a and 6b show according to the humorous diffraction microlens of the apart of the employing of this embodiment and the synoptic diagram of little picture and text.Shown in Fig. 6 a, humorousdiffraction microlens array 11 and little picture andtext array 12 are positioned at the diverse location ofSecurity element 10, present little picture and text of amplification after the two overlaps, shown in Fig. 6 b.In this case, the focal length of humorous diffraction microlens at 5 μ m in the scope of 200 μ m, preferably, at 30 μ m in the scope of 120 μ m.

The application also provides the product that has optical anti-counterfeiting element mentioned above, and said product includes but not limited to all kinds of high safety products and high value added products such as banknote, credit card, passport, securities, and each wrapping paper, packing box etc.

Some preferred embodiment of the application has below exemplarily been described.And will be understood by those skilled in the art that under the prerequisite that does not depart from the application's design and spirit and can make various equivalents or modification to it.And the technical scheme that so obtains also should belong to the application's scope.

Claims (36)

1. optical anti-counterfeiting element comprises:

Basic unit has first surface and second surface;

Humorous diffraction microlens array is positioned at the said first surface of said basic unit; And

Little picture and text array is positioned at the said second surface of said basic unit;

Wherein, said basic unit is local at least transparent, and its thickness is provided so that said little picture and text array is positioned near the focal plane of said humorous diffraction microlens array,

Wherein, said humorous diffraction microlens array comprises a plurality of humorous diffraction microlens, and said little picture and text array comprises a plurality of little picture and text unit, and the position of said a plurality of humorous diffraction microlens and said a plurality of little picture and text unit is complementary,

The color of said little picture and text unit and the blaze wavelength of said humorous diffraction microlens coupling.

2. optical anti-counterfeiting element as claimed in claim 1, wherein, said humorous diffraction microlens is the humorous diffraction microlens of transmission-type.

3. optical anti-counterfeiting element as claimed in claim 1, wherein, said humorous diffraction microlens is the humorous diffraction microlens of reflection-type that has the reflection horizon.

4. optical anti-counterfeiting element as claimed in claim 1, wherein, the level of said humorous diffraction microlens is inferior to be 1 to 15.

5. optical anti-counterfeiting element as claimed in claim 4, wherein, the level of said humorous diffraction microlens is inferior to be 3 to 7.

6. optical anti-counterfeiting element as claimed in claim 1, wherein, said humorous diffraction microlens and said little picture and text unit are periodic arrangement.

7. optical anti-counterfeiting element as claimed in claim 6, wherein, the arrangement cycle of said humorous diffraction microlens at 20 μ m in the scope of 200 μ m.

8. optical anti-counterfeiting element as claimed in claim 7, wherein, the arrangement cycle of said humorous diffraction microlens at 50 μ m in the scope of 100 μ m.

9. optical anti-counterfeiting element as claimed in claim 1, wherein, said humorous diffraction microlens and said little picture and text unit are no periodic array.

10. optical anti-counterfeiting element as claimed in claim 1, wherein, the thickness of said humorous diffraction microlens at 0.3 μ m in the scope of 15 μ m.

11. optical anti-counterfeiting element as claimed in claim 10, wherein, the thickness of said humorous diffraction microlens at 0.5 μ m in the scope of 8 μ m.

12. optical anti-counterfeiting element as claimed in claim 1, wherein, the focal length of said humorous diffraction microlens at 5 μ m in the scope of 100 μ m.

13. optical anti-counterfeiting element as claimed in claim 12, wherein, the focal length of said humorous diffraction microlens at 10 μ m in the scope of 30 μ m.

14. optical anti-counterfeiting element as claimed in claim 1, wherein, said little picture and text array by holography, printing, ink-jet, impression, laser ablation, dyeing, photochromic, partially metallised, UV duplicates or one of micro-nano structure pattern or its constitute.

15. optical anti-counterfeiting element as claimed in claim 1 further comprises one or more functional layers, said functional layer comprises protective seam, tack coat and/or its combination.

16. optical anti-counterfeiting element as claimed in claim 1; Comprise that further the liquid crystal light that is not amplified by microlens array becomes characteristic, diffraction light change characteristic, interference light change characteristic, micro-nano structure characteristic, print characteristics, partially metallised characteristic, fluorescent characteristics, and be used for machine-readable magnetic characteristic.

17. optical anti-counterfeiting element as claimed in claim 1, its thickness are less than or equal to 50 μ m.

18. the optical anti-counterfeiting element comprises:

Basic unit comprises the first and the second portion of space certain distance;

Be arranged at the humorous diffraction microlens array of said first; And

Be arranged at little picture and text array of said second portion,

Wherein, The said first of said basic unit and said second portion are local at least transparent; And the thickness of said basic unit is set to when through folding when said first is overlapped with said second portion, and said little picture and text array is positioned near the focal plane of said humorous diffraction microlens array.

19. optical anti-counterfeiting element as claimed in claim 18; Wherein, Said humorous diffraction microlens array comprises a plurality of humorous diffraction microlens, and said little picture and text array comprises that a plurality of little picture and text unit constitutes, and the position of wherein said a plurality of humorous diffraction microlens and said a plurality of little picture and text unit is complementary.

20. optical anti-counterfeiting element as claimed in claim 19, wherein, said humorous diffraction microlens is the humorous diffraction microlens of transmission-type.

21. optical anti-counterfeiting element as claimed in claim 19, wherein, said humorous diffraction microlens is the humorous diffraction microlens of reflection-type that has the reflection horizon.

22. optical anti-counterfeiting element as claimed in claim 19, wherein, the level of said humorous diffraction microlens is inferior to be 1 to 15.

23. optical anti-counterfeiting element as claimed in claim 22, wherein, the level of said humorous diffraction microlens is inferior to be 3 to 7.

24. optical anti-counterfeiting element as claimed in claim 19, wherein, said humorous diffraction microlens and said little picture and text unit are periodic arrangement.

25. optical anti-counterfeiting element as claimed in claim 24, wherein, the arrangement cycle of said humorous diffraction microlens at 20 μ m in the scope of 200 μ m.

26. optical anti-counterfeiting element as claimed in claim 25, wherein, the arrangement cycle of said humorous diffraction microlens at 50 μ m in the scope of 100 μ m.

27. optical anti-counterfeiting element as claimed in claim 19, wherein, said humorous diffraction microlens and said little picture and text unit are no periodic array.

28. optical anti-counterfeiting element as claimed in claim 19, wherein, the thickness of said humorous diffraction microlens at 0.3 μ m in the scope of 15 μ m.

29. optical anti-counterfeiting element as claimed in claim 28, wherein, the thickness of said humorous diffraction microlens at 0.5 μ m in the scope of 8 μ m.

30. optical anti-counterfeiting element as claimed in claim 19, wherein, the focal length of said humorous diffraction microlens at 5 μ m in the scope of 200 μ m.

31. optical anti-counterfeiting element as claimed in claim 30, wherein, the focal length of said humorous diffraction microlens at 30 μ m in the scope of 120 μ m.

32. optical anti-counterfeiting element as claimed in claim 19, wherein, the color of said little picture and text unit and the blaze wavelength of said humorous diffraction microlens coupling.

33. optical anti-counterfeiting element as claimed in claim 18, wherein, said little picture and text array by holography, printing, ink-jet, impression, laser ablation, dyeing, photochromic, partially metallised, UV duplicates or one of micro-nano structure pattern or its constitute.

34. optical anti-counterfeiting element as claimed in claim 18 further comprises one or more functional layers, said functional layer comprises protective seam, tack coat and/or its combination.

35. optical anti-counterfeiting element as claimed in claim 18; Comprise that further the liquid crystal light that is not amplified by microlens array becomes characteristic, diffraction light change characteristic, interference light change characteristic, micro-nano structure characteristic, print characteristics, partially metallised characteristic, fluorescent characteristics, and be used for machine-readable magnetic characteristic.

36. comprise product like each described optical anti-counterfeiting element among the claim 1-35.

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