CN1854944A - Patterned structures with optically variable effects - Google Patents

Abstract

An optical structure is disclosed that includes a light transmissive substrate having a surface relief pattern, such as a hologram, applied thereon. One or more layers may be patterned corresponding to the material acting as an absorber or reflector on a Fabry-Perot type optical structure. These materials are applied over portions of the surface relief pattern to form alphanumeric characters, bar codes, or graphic or pictorial designs. Additional layers may be applied to the patterned layer of reflective or absorbing material and to the exposed portions of the surface relief pattern in order to provide the desired optical effect to the exposed portions of the surface relief pattern. In some embodiments, the optically active coating is a photochromic film, or comprises a photochromic plate based on a Fabry-Perot design. Optionally, the refractive index of the optically active coating material is matched or mismatched to the light transmissive substrate in order to optically clear or enhance the effect of the surface relief pattern in portions of the surface relief pattern not covered by reflective or absorbing material.

Description

Patterned structures with optically variable effects

technical field

[01] The present invention generally relates to surface relief pattern structures. More specifically, the present invention relates to patterns associated with patterned structures thereon, such as holograms or diffraction gratings.

Background technique

[02] Diffractive patterns and reliefs, and related art holograms, have a wide range of practical applications due to their aesthetic and practical visual effects. Typically, a diffraction grating is essentially a repeating structure of lines or grooves in the material to form a peak and groove structure. When a diffraction grating has grooves spaced from one another in the range of hundreds to thousands of lines per millimeter on the reflective surface, the desired optical effect can be produced in the visible spectrum. One decorative effect is the iridescent visual effect produced by diffractive gratings.

[03] Diffraction grating technology has been applied to the formation of two-dimensional holographic patterns that produce the illusion of a three-dimensional image to the observer. Also, using a vertically intersecting laser beam including a reference beam and an object beam, three-dimensional holograms have been developed based on differences in refractive index in polymers. Such holograms are called volume holograms or 3D holograms. In addition, the technology of using holographic images on various objects to deter counterfeiting has been widely used.

[04] Several applications currently exist for embossed surfaces with holographic patterns ranging from decorative packaging such as those made with ribbons to security documents such as banknotes and credit cards. Two-dimensional holograms generally utilize diffractive patterns that have been formed on a plastic surface. In some cases, holographic images embossed on such surfaces can be seen without further processing; however, to achieve maximum optical effect, a reflective layer, typically a thin layer of metal such as aluminum, must usually be provided on the embossed surface . The reflective layer substantially increases the visibility of the diffractive pattern relief.

[05] Every type of first-order diffractive structure, including conventional holograms and grating images, has major disadvantages, even when encapsulated in rigid plastic.

[06] When a diffuse light source is used to illuminate a holographic image, the diffraction orders expand and overlap so that the diffracted color is lost and less visible information contained in the hologram is displayed. Typically only silvery reflections from the relief surface are seen, and all such patterns appear silvery or pastel at best under such viewing conditions. Thus, holographic images typically require direct one-way illumination to be seen. This means that for best viewing results, the direction of the illuminating light must lie in the same plane as the viewing direction. Although in practice, many point light sources are available through indoor lighting to make the hologram easily visible.

[07] As security holograms have become widely used, counterfeiters are tempted to reproduce the holograms often used in credit cards, banknotes, etc. Therefore, the security hologram must overcome the difficulty that the hologram is easy to be forged, so as to realize real security. One-step and two-step optical replication, direct mechanical replication, and even re-creation have been widely discussed on the Internet. A variety of boycotts have been developed, but no single boycott has been found to be an effective deterrent when used alone.

[08] A further problem with security holograms is that it is difficult for most people to recognize and recall the individual images produced by these holograms for authentication purposes. The average person's ability to verify security holograms is ultimately compromised by the complexity of their features and confusion of decorative diffractive packaging. Thus, most people tend to verify the existence of such security patterns rather than verifying the authenticity of the image. This opens up opportunities for the use of inferior knockoffs or generic hologram substitutes for genuine security holograms.

[09] In other efforts to thwart counterfeiters, the hologram industry has resorted to more complex images such as generating multiple images as the security pattern is rotated. These improved images provide a high level of "sparkle" or aesthetic appeal to the viewer. Unfortunately, this added complexity does not come with increased safety because this complex imaging is difficult to visualize and difficult even if one might remember it.

[10] In a further effort to provide a security pattern, US Patent 6,903,850 attempts to provide a security pattern having a substrate formed thereon in a surface relief defining an optically variable effect generating structure having at least two A different reflection-enhancing material is provided on the substrate so that the optically variable effect can be observed against a background defined by the reflection-enhancing material. Nevertheless, the optically variable effect is only a diffractive effect provided by the surface relief structure, and the contrast between diffractive regions of two different colors does not provide a very significant optical effect.

[11] The US patent application 20050063067 published in the name of Phillips et al. on March 24, 2005 is a significant improvement on the above US patent. Phillips et al. disclose two optical structures in which a substrate with a surface relief hologram is coated in selected areas with a reflective coating. The reflective coating is then applied with one or more color changing coatings. When one looks at the structure from the viewing side, the area adjacent to the reflective area is notably coated with a color changing coating, in the form of a layer comprising a Fabry-Perot filter, or alternatively Alternatively have a single layer of color shifting ink. Although these two structures have significant advantages over the prior art, they suffer from different limitations. For example, the embodiment described above with a Fabry-Perot filter coated over a relief reflectively coated hologram provides relatively high chromaticity in the color shifting region, and high reflectivity in the reflectively coated region and diffraction, however the deposition of four or more layers is required to achieve this result. Alternatively, providing a reflective area coated over the hologram, followed by coating the reflective coating and non-coated areas of the substrate with a color shifting ink, achieves a low chroma and color shifting effect with only two layers, while having a relatively strong diffraction effect. However, it is desirable to achieve a strong color shifting effect of the highest quality with a deposition of only three layers, while having a relatively strong diffractive effect, or having a weaker diffractive effect as desired.

[12] Furthermore, it is advantageous to manufacture a Fabry-Perot (FP) filter by depositing layers, and to have regions adjacent thereto devoid of layers in the Fabry-Perot filter, whereby, A non-FP filter adjacent to an FP filter can be fabricated simply by excluding or removing some material from at least one FP filter layer.

[13] The term "non-FP filter" here means an optical filter with a multilayer configuration in which the layers do not form the absorbing, dielectric and reflective film stacks that form Fabry-Perot filters, more specifically filters that have or share reflective, dielectric or absorbing layers with an adjacent FP filter, however, are present in an adjacent FP filter At least one layer of is absent in non-FP filters.

[14] This patent application provides several embodiments, the preferred embodiment of which requires three layers to realize the Fabry-Perot structure, and wherein when one observes the Fabry-Perot structure, adjacent regions have At least one thinner layer to provide the desired strong or weak diffractive effect. Of course, combinations of other effects may also be provided, however the present invention provides a structure in which the Fabry-Perot filter and the Fabry-Perot filter are adjacent to each other so as to provide contrasting visible features, And wherein the Fabry-Perot filter has fewer layers than its adjacent Fabry-Perot filter. Conveniently, the layers of the Fabry-Perot structure are shared with the layers of the Fabry-Perot filter, however the two filters are visually distinguishable, providing different optical effects.

[15] Therefore, it would be highly advantageous to develop improved security products that provide enhanced viewing quality under a variety of lighting conditions, as well as make counterfeiting more difficult in a variety of security applications.

Contents of the invention

[16] The present invention provides an optical structure capable of displaying the effect of surface relief patterns, such as holograms or diffraction gratings, and patterns such as alphanumeric characters, bar codes, or graphic or pictorial designs, and surrounding Additional optical effects in areas of these patterns. This optical structure is very useful as an anti-counterfeiting pattern.

[17] More specifically, an optical structure according to the present invention comprises a light transmissive substrate having a surface relief pattern applied thereon to provide a hologram or other relief based surface structure. In a preferred embodiment, a patterned Fabry-Perot structure with a color shifting effect is applied to part of the surface relief pattern in order to form a pattern or structure, such as an alphanumeric character, a barcode, or a pictorial or graphic pattern. The patterned layer provides a discolored region where other regions adjacent to the discolored region lack one or more layers, thereby forming a pattern.

[18] According to the present invention, an optical structure is provided, comprising:

a substrate with a first surface having a relief structure at least in predetermined areas;

side-by-side alternating Fabry-Perot type and Fabry-Perot type filter arrays having a first layer deposited on the first surface, the alternating filters being mutually Arranged adjacently, wherein the Fabry-Perot filter has a three-layer structure including an absorbing layer, a dielectric layer and a reflective layer, and wherein the Fabry-Perot filter lacks At least one of the three layers in the Fabry-Perot filter, wherein at least one of the three layers covers the Fabry-Perot type filter and the Fabry-Perot type filter optical device.

[19] According to the present invention, an anti-counterfeiting pattern is provided, comprising:

A substrate formed with a surface relief defining an optically variable effect generating structure; and a three-layer color shifting coating, wherein at least one of said layers is different on the same side of the substrate as the surface relief. Successively, each of the three layers has a surface relief profile, wherein diffractive and color shifting effects are visible as a function of viewing angle, and wherein at least two distinct regions are visible.

[20] These and other features of the present invention will become more apparent from the following description and appended claims, or may be learned by practice of the invention as hereinafter described.

Description of drawings

[21] In order to further clarify the above and other advantages and features of the invention, a more particular description of the invention will be described by reference to specific embodiments which are illustrated in the accompanying drawings. It is understood that the drawings depict only typical embodiments of the invention and therefore should not be considered as limiting its scope. The invention will be described and explained with additional features and details by means of the accompanying drawings, in which:

[22] Figure 1 is a schematic depiction of an optical structure according to an embodiment of the invention, wherein thin films and diffractive interference effects are visible in one region of the structure when viewed from the top, and weak Diffraction interference effect.

[23] FIG. 2 is a schematic depiction of an optical structure according to another embodiment of the present invention, wherein combined thin film interference and diffractive interference effects are visible from the top left, and wherein the diffractive interference effect is visible from the top right.

[24] Figure 3 is a schematic depiction of an optical structure where combined thin film and diffractive interference effects are visible when viewed from the top right, and where thin film interference and weak diffractive interference effects are visible when viewed from the top left of the pattern .

[25] Figure 4 is a schematic depiction of an optical structure in which the combined thin film and diffractive interference effects are visible when viewed from the top right, and in which the interference effect is not visible when viewed from the top left of the pattern because of the use of The dielectric layer is a low refractive index material and its refractive index is close to that of the relief resin and adhesive layer.

[26] Figure 5 is a schematic depiction of an optical structure where the combined film and diffractive interference effects are visible when viewed from the top right, and where weak diffractive interference effects are visible when viewed from the top left of the pattern, which is Due to the high refractive index material is used as a dielectric layer.

[27] FIG. 6 is a schematic diagram of an optical pattern in which thin film interference effects can be observed from the top left of the pattern, and in which diffraction interference effects can be observed from the top right of the pattern.

[28] FIG. 7 is a schematic illustration of an embodiment of the invention where combined thin film interference and diffractive interference effects are visible from the top right surface, and where the diffractive interference effect is visible from the top left surface.

[29] Fig. 8 is a schematic diagram depicting an optical structure in which combined thin-film and diffraction interference effects are evident when viewed from the right side of the top, and in which thin-film interference and weak Diffraction interference effect.

[30] Figure 9 shows an embodiment of the invention where the combined thin film and diffractive interference effects are evident when viewed from the right side of the top, and where due to the high refractive index dielectric layer when viewed from the left side of the top However, there are thin film interference and weak diffraction interference effects.

Detailed ways

[31] The present invention relates to an optical structure comprising a surface relief pattern providing optical effects such as a hologram and a diffraction grating; a patterned reflective structure underlying the surface relief pattern; and an optically active coating, the optically active coating The coating layer underlies the patterned layer and those portions of the surface relief pattern not covered by the patterned layer. The resulting optical structure exhibits unique optical effects.

[32] The drawings illustrate various aspects of the invention in schematic form, in which like structures are designated with like reference numerals.

[33] FIG. 1 depicts an optical structure 20 comprising a light transmissive layer 22 having a surface relief pattern 24 on its inner or lower surface.

[34] The Cr layer 26 is coated on the surface relief pattern so as to underlie the surface relief pattern. The Cr layer may be applied directly to the surface relief pattern, as shown, or there may optionally be one or more transmissive layers between the surface relief pattern and layer 26 . A _MgF2 layer 28 is also deposited on the Cr layer in the form of a surface relief pattern. A patterned reflective layer 29 of Al or other highly reflective material is applied over layer 28 .

[35] By use of the term "patterned" layer, it is meant that a patterned layer is applied to the surface, the patterned layer being deposited on the surface in such a way as to form a desired "pattern" or design. By way of non-limiting example, patterned reflective layer 29 may be formed in the shape of letters, numbers, barcodes, and/or pictorial or graphic designs.

[36] The light-transmitting layer 22 is preferably composed of a material capable of receiving a relief structure directly on its surface. Suitable materials for use as layer 22 include plastic materials such as polyvinyl chloride, polycarbonate, polyacrylate and PETG (PET type G).

[37] The surface relief pattern 24 can take a variety of forms, including diffraction gratings, holographic patterns such as two-dimensional and three-dimensional holographic images, corner prism reflectors, zero-order diffraction patterns, moiré patterns, or other optical interference patterns, including Patterns based on microstructures with dimensions in the range of about 0.1 μm to about 10 μm, preferably about 0.1 μm to about 1 μm, and various combinations including the above such as holographic/grating images, or other interference patterns. For example, a Kinegram(R) pattern has a two-dimensional, computer-generated image (commercially available from OVD Kinegram, Switzerland) in which individual pixels are filled with light diffractive microstructures. These microstructures are very fine surface modulation structures with typical dimensions of less than about 1 μm. In addition to conventional holograms, the invention is applicable to any relief structure that can be embossed in a resin layer. This includes diffractive surfaces, "moth-eye" type structures, holograms with multiple viewing angles, where each viewing angle has a different holographic feature or image, or can include high-resolution reliefs from a nickel master, where the original is passed through the Produced by high-resolution laser etching.

[38] A method of forming the surface relief pattern 24 is known to those skilled in the art. For example, the surface of layer 22 may be embossed by known methods, such as by contacting the layer with a heated nickel relief plate under pressure at elevated temperature. Other methods include photolithography and molding plastic substrates with patterned surfaces.

[39] In one approach, the optical structure 20 can be fabricated from a thermoplastic film that is embossed by heat softening the surface of the film and then passing the film through embossing rolls that transfer a diffractive grating or holographic image to the That softens the surface. In this way, effectively infinite length flakes with diffraction gratings or holographic images thereon can be formed. Alternatively, the optical structure 20 can be obtained by passing a roll of plastic film coated with an ultraviolet (UV) curable polymer, such as PMMA, through a set of UV transparent rolls, whereby the rolls set the pattern in the UV curable polymer, and then The polymer is cured by UV light passing through a UV transparent roller.

[40] Once the light transmissive layer and associated surface relief structures are prepared, and after layers 26 and 28 are deposited, a reflective material is deposited in the desired pattern to form patterned reflective layer 29 . Although other reflective or even partially reflective/partially transmissive materials may also be used, the presently preferred materials for the patterned reflective layer are metals such as aluminum, silver, nickel, silver palladium alloys, silver copper alloys, copper, gold, and the like. Although it should be understood that the layer may be partially transmissive in order to obtain the desired effect, it is preferred that the layer is substantially opaque in order to enhance the optical properties of the associated surface relief pattern. In cases where the reflective layer is substantially opaque, the metal layer is typically formed to a thickness between about 50 and about 100 nm.

[41] It is presently preferred to apply the patterned reflective layer in the desired pattern/design using one of two methods. In one approach, standard photolithographic techniques are used in which the pattern is developed by UV curing through a mask in a photoresist layer formed on the metal layer, and then in an alkaline solution such as sodium hydroxide (NaOH) solution Processing is performed to remove the photoresist layer. In another method, the pattern of the metal layer is embedded (in-line) in a roll-to-roll vacuum coater by gravure printing the pattern on the relief surface with non-wetting oil, thereby, generating the patterned surface during the deposition process. metal layer. The pattern is created by the evaporation of the oil as the metal is deposited on the relief-coated surface. In those areas where oil is absent, metal will deposit and adhere to the resin layer or substrate surface. In those areas where oil is present on the surface, the oil evaporates due to the heat of condensation of the deposited metal, and a relief structure such as a hologram has no metal layer on those areas, resulting in a non-metallized relief structure. The third method involves printing of an insoluble organic resin pattern, followed by chemical etching to remove portions not protected by the insoluble organic pattern, followed by removal of the insoluble resin by a solvent capable of removing the insoluble resin. For example, if aluminum is patterned by this method, a technician can print an organic water-insoluble pattern, then use a caustic solution to etch away the pattern in the aluminum layer that is not protected by the organic printed pattern, and then use an organic solvent to wash away the remaining pattern. The organic patterns that exist.

[42] While these three methods of forming the patterned reflective layer are presently preferred, it should be understood that alternative methods of forming the patterned reflective layer may be found by those skilled in the art who understand the desired structures disclosed herein.

[43] In Fig. 1, regions with Cr, _MgF2 and Al form a Fabry-Perot thin-film interference filter, which can be seen when viewing the structure from the top. Furthermore, the combined diffractive effect is visible with the optically variable properties provided by the FP filter. When the image is viewed from the upper left, only a weak diffractive effect is seen, since the filter is not an FP filter, no reflective layer 29 is present in the contrasting areas of the pattern. Conveniently, by providing three layers of FP filters in some areas, and having one of the three layers absent, these two different optical effects can be seen. Essentially the Cr and MgF ₂ layers are shared by FP and non-FP filters; and in this example the Al layer is only present in the FP filter. The absence of a layer provides a completely different optical effect and contrast between the two areas.

[44] FIG. 2 depicts a structure similar to FIG. 1 , but showing a patterned layer 36 of Cr beneath the light transmissive layer 22 . On top of the partially patterned Cr layer and the uncoated adjacent complementary portion lacking Cr is a full _MgF2 layer 38 on which is coated a full Al layer 39 . Thus in this embodiment the inner surface 32 of the light transmissive layer has a surface relief pattern 34 on which Cr is formed. When viewing the structure from the top left, combined diffraction and thin film interference effects can be seen due to the presence of a Fabry-Perot filter under the substrate on the left. When viewing the structure from the top right, only diffractive interference effects are seen due to the absence of Fabry-Perot filters in this region.

[45] It is presently preferred to use moldable thermoformable materials to form light transmissive substrate 32, which include, for example, plastics such as polyester, polyethylene terephthalate (PET) such as PET Type G, polycarbonate, acrylic resins such as Polyacrylates including polymethyl methacrylate (PMMA), polyvinyl chloride, polyvinylidene chloride, polystyrene, cellulose diacetate and cellulose triacetate, mixtures or copolymers thereof, and the like. In a preferred embodiment, the light transmissive substrate 32 consists essentially of a transparent material such as polycarbonate. The shaped substrate 32 has a suitable thickness of about 3 μm to about 100 μm, and preferably a thickness of about 12 μm to about 25 μm. Although substrate 32 is described as being formed from a single layer, it may be formed from multiple layers of substrate material.

[46] Referring now to FIG. 3, there is shown an optical structure in which a relief PET layer 126 has a Cr layer 122 and a _MgF2 layer 123 deposited thereon, followed by a portion of an Al layer 124 for providing a deposited Al layer 124 Windowless regions of and windowed regions lacking Al along the same layer. Underneath the Al layer 124 is an ink layer 127 comprising an optically variable membrane sheet, which is supported by the base layer 120 . Although the substrate support layer is referred to as a substrate, the PET relief layer 126 may also be considered a substrate in this specification. In operation, the pattern provides a combined thin film and weak diffractive interference effect when viewed from the top left, and a combined strong thin film and diffractive interference effect when viewed from the top right.

[47] An alternative embodiment of the present invention is depicted in FIG. 4 . In this embodiment, separate influence effects to the right and left of the dotted line are shown when viewed from the top. On the right, the observer will notice the combined thin film and diffractive interference effects. There are no interference effects on the left. The PET substrate 136 with an embossed diffraction grating on one side is coated with a multilayer optical coating consisting of a partially absorbing/partially transmitting layer, an optical dielectric layer and a reflective layer, the partially absorbing/partially transmitting layer Hereafter referred to as the "absorbent" layer. The three layers form a Fabry-Perot structure. According to teachings in patents such as US 5,135,812, the entire contents of which are incorporated herein by reference, these layers will add a color changing feature to the optical structure, meaning that the color will change depending on the viewing angle. The color-changing coating in this embodiment includes part of the Cr layer 132 . Another part of the Al layer 134 is deposited on part of the layer 132, wherein the layers 132 and 134 have a relief pattern of the grating formed therein. Sandwiched between layers 132 and 134 is a complete _MgF2 layer 133 which coats the Cr layer 132 and the exposed portions of the surface relief pattern on the PET substrate. The structure is secured to the substrate 130 via an adhesive layer 138 .

[48] Figure 5 is very similar to Figure 4, however instead of coating the substrate with a _MgF2 layer 133 as shown in Figure 4, a high dielectric layer 142 composed of ZnS is used. In this case the performance is similar in most respects, however in Figure 5 the film discoloration effect is significantly reduced and when viewed from the top on the left side of the pattern it can be observed that the weak diffraction effect.

[49] Referring now to FIG. 6, an optically variable photochromic film stack is shown deposited on a PET substrate with a demetallized aluminum hologram on the upper surface of the substrate. The PET substrate 156 has a holographic surface relief pattern deposited in its upper surface. The protective paint layer 159 undulates along the waves of the relief pattern. Part of the Al layer 154 covers the relief pattern area on the PET substrate 156 and is sandwiched between the layer 159 and the PET substrate 156 . Optically variable layer film stack 152 is disposed between PET substrate 156 and substrate 150 .

[50] FIG. 7 is a structure very similar to FIG. 6, however instead of having an Al layer only partially covering the PET substrate, a complete Al layer 174 is provided and a partial layer 176 is provided. MgF ₂ layers span the entire structure. In this example, the combined diffractive and thin film interference effects are visible from the top right, and the diffractive interference effects are visible from the top left.

[51] Figure 8 shows an embodiment of the present invention, a combined thin film interference and diffraction interference effect can be seen when viewing the structure from the top right, and a thin film interference and weak diffraction effect can be seen from the top left of the pattern. The structure is formed by providing a substrate 180 on which is deposited an optically variable ink layer 181 with a thick PET layer or substrate 186 having a grating formed therein on its top surface. The aluminum layer 184 partially covers the PET grating and takes the form of a grating. A _MgF2 layer 185 covers the Al layer 184 and the non-aluminized PET grating. The Cr layer 186 covers the MgF ₂ layer 185 . A protective paint layer 187 covers the Cr layer 186 . Alternatively, in other embodiments an optically variable foil may be used in place of the pigment layer 181 .

[52] The embodiment in FIG. 9 is very similar to FIG. 8 , however with a ZnS layer 195 in place of the MgF ₂ layer 185 and a portion of the Cr layer 196 in place of the Cr layer 186 . It should be noted that in the preceding description, partial layers were described as partially deposited, but could also be "demetallized" using in-situ oil printing/ablation methods, or chemically etched using photolithographic means, or by printing insoluble patterns, This is followed by chemical etching followed by selective solvent etching to remove the insoluble pattern, thereby removing the deposited portion so as to create partial layers, resulting in windowed and windowless areas.

[53] The present invention may be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention. The described examples are to be considered in all respects as illustrative only and not restrictive. Accordingly, the scope of the invention is indicated by the appended claims rather than the foregoing description. All changes within the meaning and range of equivalents of the claims are embraced in their scope.

[54] In summary, the present invention provides structures that only require the deposition of three layers of material on a light transmissive substrate, on which a hologram or grating or the like is present. Conveniently, by omitting one or more of the three layers in a predetermined area, a different optical effect can be seen, thereby producing at least two distinguishable areas. The most prominently visible effect is the thin film interference effect, which has or is close to a diffractive effect.

Claims (17)

1. An optical structure having a first side and a second side, wherein at least one of the first side and the second side is a viewing side from which a pattern can be seen, the optical structure comprising : a substrate with a first surface having a relief structure at least in a predetermined area of said first surface; side-by-side Fabry-Perot type and Fabry-Perot type filters, the filter being visible from the viewing side, each of the side-by-side filters having a layer deposited on the The first layer on the first surface, wherein the Fabry-Perot type filter is a color changing filter for providing a visible color change as the angle or viewing angle of the incident light changes, and Each of the Fabry-Perot type filters has the same three ordered layers, the three layers including an absorbing layer, a dielectric layer and a reflective layer, and the Fabry-Perot filter The filter lacks at least one of the three layers present in the Fabry-Perot filter, and the Fabry-Perot filter and the Fabry-Perot filter The visible optical effects are clearly distinguishable. 2. Optical structure according to claim 1, characterized in that said side-by-side Fabry-Perot type and Fabry-Perot filter arrangements form a filter array. 3. The optical structure of claim 2, wherein the filter array forms a visible repeating periodic pattern. 4. The optical structure of claim 1, wherein each of said Fabry-Perot filters consists of only three layers. 5. Optical structure according to claim 4, characterized in that the maximum number of optically active layers deposited on the relief structure is three. 6. The optical structure according to claim 1, wherein the Fabry-Perot filter has no color changing effect. 7. Optical structure according to claim 6, characterized in that the Fabry-Perot filter exhibits visible diffractive effects. 8. Optical structure according to claim 1, characterized in that the Fabry-Perot filter exhibits visible diffraction effects as well as color changing effects. 9. The optical structure of claim 1, wherein an alternating color change and diffractive effect is visible when the filter is viewed from the viewing side. 10. The optical structure of claim 1, wherein the relief structure runs through the surface of the substrate. 11. The optical structure according to claim 1, wherein the relief structure exists only in the region where the Fabry-Perot filter exists, or In alternate regions corresponding to the region where the optical device exists. 12. The optical structure of claim 1, wherein the absorbing layer is Cr, and the dielectric and reflective layers are _MgF2 and Al, respectively. 13. The optical structure of claim 1, wherein the dielectric layer is a high refractive index material having a refractive index of 1.65 or greater. 14. The optical structure of claim 1, wherein only a single highly reflective layer is present. 15. The optical structure of claim 6, wherein the absorbing layer is aluminum and the dielectric and reflective layers are _MgF2 and Al, respectively. 16. The optical structure of claim 1, wherein said juxtaposed Fabry-Perot and Fabry-Perot filters together form a visible logo, sign or lettering because Fabry-Perot and Fabry-Perot filters are distinguishable by differences in their optical properties. 17. The optical structure of claim 1, wherein said side-by-side Fabry-Perot and Fabry-Perot filters share at least one of said three layers.

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