Relief microstructures of surface with optical effects and method of making said microstructures

FIELD: physics.

SUBSTANCE: relief microstructure of the surface has protrusions and depressions, where in the first cross direction of an area of the surface there is an average of at least one transition from a protrusion to a depression or vice versa in every 20 mcm, and in the second cross direction of a pattern which is perpendicular to the first direction, there is an average of at least one transition from a first zone to a second zone or vice versa in every 200 mcm. The microstructure is characterised by that in the first direction the lateral arrangement of transitions is non-periodic and that protrusions mainly lie in the same top relief plateau and the depressions mainly lie in the same bottom relief plateau. Due to scattering effects, the surface relief microstructures are suitable for displaying images with a sharp transition between negative and positive images.

EFFECT: well distinguished and saturated image colours and absence of rainbow colours.

18 cl, 39 dwg

 

The technical field to which the invention relates.

The invention relates to optical devices that create a distinctive color impressions and which can be used, for example, to protect documents and various products from counterfeiting and forgery.

In particular, the invention relates to elements that have at least one portion of the surface to create the optical effect of relief microstructure surface, and to methods of making such elements.

The level of technology

Currently, the use of optical devices to protect against counterfeit and forgery, unauthorized manipulation and protection products in General is a well-developed field.

Because cases of fraud and scams are becoming more frequent, then there is a constant need for new tools to combat counterfeit products. For a long time the preferred technology in this area were associated with the use of holograms. I must say that this technology for over 30 years, and because it is well known and widespread. Film holograms can be found now in almost every gift shop and Souvenirs. The situation may be dangerous, because many people have access to technology holograms. The availability of digital is holegraficheskih printers further simplifies the possibility of using technical means of production of the master matrix holograms. These printers provide the ability to manufacture various types of holograms, and requires only minimal knowledge in the field of printers and technology of holography. Such equipment can be obtained a master matrix, which can then be used to manufacture metal working matrix for replication of holograms in large quantities on thin films.

Thus, there is an urgent need to develop new technical means of protection, the principle of action which would not be associated with a holographic device. Examples of such new devices are devices with varying optical properties. Such devices are characterized in that their appearance changes when you change the angle or lighting. One variation of this type of devices are devices with a color shift. Device with a color shift change color when you change the angle or lighting. Most known devices with color shift are cholesteric or interference films, including optical devices, based on the records of such films. They show a pronounced color shift when their turns and bends. Resulting effect has nothing to do with the effect of iridescent play of colors, typical of standard Golo is raficheskih device mass production.

Using the effects of the color shift due to the interference of light in thin optical films has a long tradition in the technique of modern thin-film components (see, e.g., the publication of “thin-film optical protective device” release “means of Optical document security”, edited by RLAN-Renesse, ed. “Artechouse, Boston, mA, 1998). There are a variety of compositions multilayer thin film systems. For example, when light is incident at a right angle occurs the characteristic spectrum of the reflected light. The spectra of the reflected or captured light are shifted into the region of shorter wavelengths with increasing angle of incidence. Multilayer thin-film system, which are often combinations of layers of metallization and dielectric materials can also contain only the dielectrics. In this case it is necessary to use thin films with different refractive indices.

Today in the market there are protective devices based on thin interference films or plates of such films. Examples of such devices can be found in patents US 5084351 and US 6686042 owned by the company Flex Products, Inc.

Another direction represent dispersal device. The use of the effects of dispersion, having isotropic or anisotropic in nature, in the device color shift can with the public to improve the optical attractiveness of such devices. The use of anisotropic light scattering is particularly attractive to create devices that are sensitive to the angle of observation. On Fig and 1.2 illustrates the isotropic and anisotropic light scattering, respectively.

The reflection on the surface with isotropic structure, such as newsprint or the surfaces of the items used in the household, approximately equally in all azimuthal directions. As you can see in Fig parallel to the beam 1 of the light incident on the scattering surface 2, is reflected from it in 3 directions with a characteristic symmetrical distribution relative to the axial axis and a characteristic angle 4 differences.

As for surfaces with anisotropic structure, they reflect light primarily in some areas and suppress it in other directions. On Fig parallel beam 1 light incident on the anisotropic diffusing surface 5, is reflected from it in the directions 6 with a characteristic distribution 7 light, which depends on the azimuthal angle 8, 8'.

For information reproduction can be carried out a certain arrangement of the individual surface elements with anisotropic scattering, and with different directions of anisotropic scattering. Thus, the appropriate device which may contain a surface with a certain scheme of anisotropic scattering, which can reproduce an image, such as text, image, or other types of images. Because the light is reflected or suppressed in a certain direction depending on the specific orientation of surface elements (pixels)you will see the image of light and dark elements. In addition, such devices will detect a distinct transition from a positive image to a negative when turning or tilting the device. Such devices with a specific layout of elements on the surface can be produced, for example, as follows. First get the desired raster halftone images, i.e. the image is divided into dark and light areas with a specific resolution. Then dark areas (pixels) are assigned to zones with anisotropic scattering in the first direction, and light areas are assigned to zones with anisotropic scattering in a different direction, for example perpendicular to the first direction. Figure 2 shows a view of the square containing the 2×2 pixels with defined orientations. The pixels 10 and 10' are oriented in the same direction, and the pixels 11 and 11' are oriented in the transverse direction. The device with such arrangement of the pixels will be visible as a positive image at a first viewing angle and will be seen as a negative image when turning parts, all specifications is the device by 90°.

A known method of manufacturing the anisotropic scattering film with a specific location of areas with different anisotropy is described in international publication WO 01/29148 company Rolic AG, as well as, for example, in the publication “Optical thin polymer films with isotropic and anisotropic corrugated nanorelief surface, Ibn-elhaj and others, Nature, 2001, vol 410, str-799. For the fabrication of surface structures was used so-called technology roughening of the monomers. It is based on phase separation of special mixtures, deposited on a substrate, which is induced by crosslinking, for example by irradiation with UV radiation. Subsequent removal unstitched components leads to the formation of a structure with a specific surface topography. Can be obtained anisotropic relief by focusing underlying orientation layer, and through the use of orienting layer with ordered structure, you can create a structured surface topography with anisotropic scattering.

As mentioned above, interesting and desirable feature for many applications, in particular for use in protective devices are special colors and effects of color shift. In international publication WO 2006/007742 in a single example (Example 5), in which technology is used rifle what I monomers, it is shown that in principle it is possible to reach such depths of modulation, which is sufficient to obtain the pastel colors of the visible surface. However, although the average modulation depth of the surface and the average value of its periodicity, when riffling monomers can be adjusted using several tools, it is impossible to ensure the independence of the two parameters. Therefore, and due to the characteristic shape of the recesses of the surface obtained by the techniques of embossing monomers, color saturation, created the obtained scattering surfaces is limited. More saturated colors cannot be obtained with the use of appropriate devices and it is essential for many applications.

In this regard, please refer to the publication US 2003/0072412 A1. This document describes the optical surface structure containing a substrate with a multilayer structure containing groove passing between the exposed areas. It should be noted that the structure disclosed in US 2003/0072412 A1, in principle, is periodic, since it is specifically indicated that within each repeating field are random, but within the repetitive plots use the same random combination. Thus, there is a random distribution within a single paragraph is taraudage plot which is however identical image is repeated on each subsequent plot. Thus, the structure is periodic. Similar structures are described in the document DE 102004003984 A1, as well as in the publication US 2005/0094277 A1.

Similar periodic surface structure described in the publication US 2005/0219353 A1 in connection with antireflection coatings. Although the text indicates the random placement of the speakers of optical elements, however, there is no example of such a non-periodic placement. On the other hand, describes how to get the antireflection structured coatings obviously do not allow to obtain structures with exposed optical elements, as shown in the examples, i.e. with a constant modulation depth.

In the publication US 2003/0011870 A1 discloses a substrate with a reflective film, in which a height of the convex portions or the depths of the concave portions formed in the base material is basically the same. Indicates that a two-dimensional shape of the convex or concave parts are not related to each other in circles and/or polygons. In addition, the convex or concave parts are positioned in a particular direction in the plane in a random order. The substrate is formed using a mask (template)in which transparent and opaque parts formed the groups of points, the number of which is less than the number of zones points. Points are unordered in each group, and used many such groups.

In the document JP 2005-215642 described photomask for manufacturing a diffusing reflector with high intensity of scattered light and a method of manufacturing a diffusing reflector using such a photomask. In the photomask has a structured area, and a separate structured area is placed in the matrix. Structured area has a rectangular svetopropusknuyu part numbers placed in the matrix, a small ring svetopropusknuyu part in the great room, placed a regular or random manner to surround each svetopropusknuyu part, and their surrounding shielding part. Next, svetopropusknaya part surrounded by a band in which there is no small svetopropusknaya part, and the band width is in the range of 1-5 mm

Disclosure of inventions

The present invention is the task of creating surface structures, which themselves, without requiring the use of additional elements or layers, provide (a) the effects of dispersion, which is suitable for displaying images, and fast transitions from positive to negative image without iridescent play of colors, and (who) are clearly visible and vibrant colors.

Another objective of the present invention is to develop methods of obtaining such surface structures.

Thus, one object of the invention is an element having at least one portion of the surface to create the optical effect of relief microstructure surface, which (microstructure) is a modulation of the surface, consisting of transitions from elevations to the hollows and recesses of the dais, and in one (first) transverse direction of surface area for every 20 μm has (on average) at least one transition from exaltation to deepen or Vice versa, and preferably in the second transverse direction of the surface perpendicular to the first direction, for every 200 microns has on average at least one the transition from exaltation to deepen or Vice versa, characterized in that (first) direction transverse transitions is non-periodic, and exaltation are mostly on the same level as the upper plateau terrain, and all the cavities are mostly on the same level as the lower plateau of relief, so that the modulation depth is the same and the same all over the surface.

For a more complete understanding of the above terms and further consideration is necessary to give some definitions.

As this is all right known in the art, a periodic function is a function whose values are repeated after a certain period, added to its independent variable. Unlike periodic functions for non-periodic functions can be specified certain period of time after which the function values are repeated. The frequency can be determined using various methods, one of which is the correlation function in one or more dimensions.

The specialist is well known that the plateau is part of the scope in which the function has a constant value. Therefore, in the context of the present invention the upper plateau topography and the bottom plateau of the relief is the zone in which the function that determines the surface has an essentially constant value in the direction perpendicular to the substrate plane (along the Z-direction). It should be noted that these areas are not necessarily smooth or quasiplane transitions, such as transitions, having a sinusoidal shape, between the elevations and recesses of the surface structure are a distinctive feature.

The height difference between the levels of these two plateaus remains constant or essentially constant throughout the surface area, and it changes the height difference between the two plateaus on the entire surface in the Z-direction usually is anise 20%, preferably less than 10% and more preferably less than 5%. The presence of such plateau and the fact that the height difference between the levels of these two plateaus of equal or essentially equal over the entire area, can also be expressed quantitatively using quality function, discussed below.

The axis of anisotropy is the direction along which the surface topography varies less likely, and, as a rule, it is the direction of the grooves or grooved structures of the surface relief.

The fill factor of the relief is defined as the ratio of the total area of the elevations to the total area of all of the elevations and recesses.

We can assume that sign (a) is one of the main reasons for the lack rainbow overflow colors, while the sign of (b) is the main determinant of high color saturation.

For additional features proposed in the present invention the element is inserted averaged one-dimensional autocorrelation function AC(x) embossed microstructure surface at least in one direction, which for anisotropic surface relief perpendicular to the anisotropy axis. For the autocorrelation function is entered, the length of the autocorrelation, namely that the shift value of the variable x, for which the envelope of the autocorrelation function decays to 10% meant is I AC at x=0. In the context of the present invention, the term “is non-periodic” is commonly used for conditions when the autocorrelation length of less than three times the average transverse distance between adjacent transitions between the elevations and recesses.

In accordance with a preferred embodiment of the invention the transverse location of the transitions is non-periodic in the second direction perpendicular to the first direction.

In accordance with another preferred embodiment of the invention the element is an ordered set of plots with creating an optical effect relief microstructures surface. Structure locations may represent an image, such as text or image, or may be part of an image, such as text or image. The image may also contain areas without creating optical effects relief microstructures surface. Accordingly, such areas will not be visible in rich colours, characteristic for areas with relief microstructures of the surface.

Another object of the invention is a protective device that contains such elements.

Another object of the invention is a method of manufacturing an element having at least one portion of the surface to create the optical effect rela is enoy microstructure surface. In accordance with this method you get a template that has the microstructure of the first and second zones of different transparency, and in one (first) transverse direction of the template for every 20 μm has (on average) at least one transition from the first zone to the second zone, or Vice versa, and preferably in the second transverse direction of the template, which is perpendicular to the first direction, for every 200 microns has on average at least one transition from the first zone to the second zone, or Vice versa, and in one (first) direction transverse transitions is non-periodic. Then, using the obtained pattern, get relief microstructure on the surface of the resin or photoresist with elevations corresponding to the first areas of the template, and recesses corresponding to the second areas of the template. Thus, any rise will be mainly at the level of the upper plateau terrain, and all the cavities will be mainly at the level of the lower plateau of relief, so that the modulation depth is basically the same all over the surface.

So, the essence of the method is that used by the microstructure of the first and second zones of different transparency, and in one (first) transverse direction of the template for every 20 μm has (on average) for men is our least one transition from the first zone to the second zone, or Vice versa, and preferably also in the second transverse direction of the template, which is perpendicular to the first direction, for every 200 microns has on average at least one transition from the first zone to the second zone, or Vice versa, and in the first direction transverse transitions is non-periodic, as, for example, can be easily obtained by means of the above-mentioned technologies roughening of the monomers. The disadvantages and limitations of such technologies roughening monomers can be overcome in principle by use of such a microstructure of two-dimensional anisotropic topological schemes and the use of such two-dimensional topological schema as a “template” to obtain a much more clear and distinct profile in the third direction, i.e. in the direction perpendicular to the plane of the microstructure. Such a clear and distinct profile means that the elevation obtained at the end of the structure being located on the upper plateau of relief, and deepening essentially located on the lower plateau of relief.

In the extreme case this means that a two-dimensional anisotropic topological scheme, which in principle represents a slot in the microstructure, as it may be, for example, obtained with the use of technology roughening of the monomers, is projected in the third dimension, so to have the upper plateau with the same two-dimensional that is alogia and lower plateau, representing a negative image of this two-dimensional topology, with vertical transitions between them. Other cases that are within the scope of the present invention may be characterized, for example, certain bimodal distribution in the third dimension, characterized by the function M quality, discussed below.

In accordance with the preferred embodiment proposed in the invention method, the microstructure that contains first and second areas of the template with different transparency, obtained as follows. First material layer pattern is applied film with a topologically structured corrugated surface. Then the film thickness is reduced until it is deleted material film in the lower zones of the corrugated surface will not be part of the underlying material of the template. Then remove the emerged part of the template.

The invention also relates to preferred applications of the above elements. Preferably, such elements are used as protective elements in protective devices. The protective device can be placed on the protected documents or entered into their composition.

Protected documents can be, for example, banknotes, passports, driving licences, stocks, bonds, coupons, checks, credit cards, light is eTelestia, tickets, etc. of the Protective device can also be applied to or incorporated in the mark or device protection products or in packaging tools, such as wrapping paper, packaging boxes, envelopes, etc. Preferably, the protective device can have, for example, the shape of the label, protective strips, labels, fibers, strands, layered structures or pads.

An important aspect of the present invention is the fact that create optical effects relief microstructure surface can be reproduced by appropriate technical means of reproduction, because the corresponding optical effect is determined by the transitions between the elevations and recesses of relief microstructures surface. So you can use standard technical means of mass production to mass production of such devices, and after fabrication of the master matrix, the replication cost will be quite adequate. Today there are two most common and economical technology replication is embossed using UV and hot stamping (see, for example, the publication McHale: “Technologies of replication of diffractive optical elements”, “Microelectronic Engineering, volume 34, str, 1997).

In accordance with a preferred embodiment of izaberete the Oia creates the optical effect of relief microstructure of the surface is obtained from a single material, however, for rich color of reflected light relief microstructure surface in accordance with the invention is generally covered with reflective material, such as, for example, aluminum, gold, chromium, copper.

In particular, for use in protective devices relief microstructure surfaces should be sealed to protect the device from mechanical damage, contamination, and to prevent the possibility of unauthorized and illicit manufacture exact copies of such devices. As a suitable protective and passivating films are films of transparent dielectric materials or materials with specific properties absorption, which can further improve the product's appearance in color.

Proposed in the invention, the elements can also contain high-resolution images, graphic elements, microtext, and other similar signs. Color images are typically depends on the angle, and the picture may become colorless at large angles. You can change the characteristics of dispersion of pixels in the image, so that the dispersion occurred mainly in certain directions. If the pixels with these characteristics made and posted accordingly, it is clearly expressed is i.i.d. quick switch positive/negative if you bend or bends devices.

In addition, there may be obtained a wide range of colors, for example by increasing the depth of modulation can be obtained in the following colors: yellow, orange, pink, purple, blue and green. For structures with more depth can receive the color of higher orders.

Brief description of drawings

Hereinafter the invention is described with reference to the accompanying drawings. It should be noted that the various constituent elements are not necessarily shown to scale. In the drawings shown:

on Fig is an illustration of the reflection of light on the surface with isotropic structure;

on Fig - illustration, similar pig, but it represents the distribution of the reflected light after reflection on the surface with an anisotropic structure;

figure 2 - schematic view of pixels with different directions of anisotropy;

figure 3 is a perspective view of a relief microstructures surface in accordance with the invention (photo taken with an atomic force microscope (AFM));

on Fig, 4.2 and 4.3 - schematic views of possible options anisotropic relief microstructures surface;

on Fig - AFM-image of a known holographic microstructure surface;

on Fig - type two-dimensional autocorrelation function of the AFM image Fig;

on Fig - view averaged one is measuring the autocorrelation function of the AFM image Fig (horizontally perpendicular to the anisotropy axis);

on Fig - AFM-image of the anisotropic relief microstructure surface in accordance with the invention;

on Fig - type two-dimensional autocorrelation function of the AFM image Fig;

on Fig - view averaged one-dimensional autocorrelation function of the AFM image Fig (horizontally perpendicular to the axis of anisotropy);

7 - AFM image of the microstructure shown in figure 3;

on Fig - histogram of the height of the microstructure shown in figure 3 and Fig;

on Fig-8.2 - illustrations receipt template, which is suitable for the proposed in the invention, a method of manufacturing elements with a relief surface microstructures;

on Fig-9.3 - illustrate the use of the photomask shown in Fig, in the process of contact photolithography for the manufacture proposed in the invention of item that has the surface area to create the optical effect of the relief surface microstructures;

on Fig-10.4 - illustration of another process of photolithography for the manufacture proposed in the invention of item;

on Fig and 11.2 illustration of another manufacturing process proposed in the invention of item using etching directly through the metal pattern;

on Fig-12.4 diagram of a method of manufacturing element with two from what astami surface, containing various relief microstructure surface;

on Fig and 13.2 - illustrations of examples of relief microstructures surface in accordance with the invention, which are reflective or partially reflective;

on Fig and 14.2 - types of spectra mirrored and non-mirrored reflection proposed in the invention of the reflecting element with microstructures in the range of green color.

on Fig and 15.2 - types of spectra mirrored and non-mirrored reflection proposed in the invention of the reflecting element with microstructures in the range of orange.

Embodiments of the inventions

The example proposed in the invention relief microstructure 12 surface is shown in figure 3, where you can see the perspective view image dimensions of 12×12 μm, obtained by atomic force microscope (AFM). The microstructure was fabricated in accordance with the method, the description of which is given below.

Modulation of the surface creates transitions from elevations 13 to the recesses 14. The width of the elevations 13 and recesses 14, and hence the plateau, generally is in the range of from about 200 nm to 20 μm. You can do so, and for many applications it is a requirement that the relief microstructure surface was anisotropic. Such anisotropic microstructure showing the a, for example, in figure 3. The microstructure is characterized by recesses having the shape of the grooves, which run approximately along the Y-axis, so the axis of anisotropy of relief parallel to the axis Y. For anisotropic reliefs transverse dimensions of the elevations and recesses of relief microstructures surface in accordance with the invention can be determined based on the fact that between deepening and elevation or Vice versa there is on average at least one transition for every 20 μm in the first transverse direction, and in the second transverse direction of the surface section, which is perpendicular to the first direction, between elevation and deepening or Vice versa there is on average at least one transition for every 200 microns.

Figure 3 the first direction corresponds to a direction perpendicular to the grooves, and the second direction corresponds to the direction along the grooves. Thus, in this second direction, the transitions between the grooves may be at much greater distances, or even such transitions generally may not be available throughout the microstructure.

Relief microstructure surface may form a reflecting surface. The reflective surface can be performed, for example, from a thin film of metal, such as aluminum or chromium, covering the microstructure. In an alternate embodiment, the reflection can be obtained on the transition to a material with a different refractive index. The surface microstructure can be in contact with air or may be covered with a dielectric material. The coating may also be absorbing for certain colors to improve the appearance of the device in color.

In preferred embodiments of relief microstructures surface in accordance with the invention, the average lateral distance between adjacent transitions from exaltation to deepen or Vice versa in the first transverse direction surface area is in the range from 0.5 to 10 μm. Preferably the average transverse distance is in the range from 0.5 to 5 μm. In the second transverse direction, perpendicular to the first transverse direction, the average distance between transitions from exaltation to deepen preferably not larger than 100 μm and more preferably not more than 50 μm.

The optical depth of modulation is preferably in the range from 100 to 1000 nm and more preferably in the range of from 100 to 500 nm. In the context of the present invention the depth of the optical modulation surface is equal to the product of the mechanical modulation depth of the relief on the refractive index of the material filling the modulation of the surface.

Relief microstructure surface in accordance with the invention are characterized by a very specific modulations of the surface the surface.

First, the location in the transverse direction of the transitions from elevations to the hollows and recesses of the dais is of a nonrecurring nature. This is the special difference of microstructures, for example, from optical gratings and holographic surface structures.

Secondly, all elevations are mostly on the same level as the upper plateau terrain, and all the cavities are mostly on the same level as the lower plateau of relief, so that the modulation depth of the relief is almost the same over the entire area of the surface. The levels of the upper and lower plateau elevation shown on the front of figure 3 by the dotted lines 15 and 16. In the above example, the modulation depth of relief (or the distance between the upper and lower plateau) is equal to about 290 nm. This second characteristic, which can be called “binary” relief, in particular distinguishes the proposed invention microstructure of microstructures based roughening of the monomers mentioned in the beginning of the description.

Specialists are well aware that there are a variety of natural and artificial surfaces with different characteristics of isotropic and anisotropic scattering. Well known examples of isotropic scattering surfaces are frosted glass, used, for example, in lighting systems. T is the cue scattering glass pass or reflect light evenly in all azimuthal directions of dispersion.

Optical device, the action of which is based on the anisotropic structures of the surface topography, diffuse or deflect light mainly for some specific azimuthal directions. One-dimensional scattering lenses belong to this class of optical devices. The topography z(x, y) of the surface depends only on one of the transverse coordinates, for example the coordinates of X. Thus, the axis of anisotropy in a surface parallel to the other transverse coordinate, for example the coordinate Y. the Light propagating in the plane Z-X, will be dissipated in this plane. Other examples of optical devices with anisotropic dispersion described in the above mentioned documents WO 01/29148 and WO 2006/007742. On the surface of such devices with anisotropic scattering has grooves or other relief elements, which are anisotropic and scatter light primarily perpendicular to the long thin grooves or axis other landscape elements.

A large part of the isotropic and anisotropic scatterer is intended for use in lighting systems to ensure a high degree of achromatism. They differ from those proposed in the present invention creates optical effects devices that are visible in color and is based on the scattering and interference on two levels rasayani the terrain.

The anisotropy of the surface topography allows you to increase the brightness of the device and create a striking visual effects, such as, for example, abrupt transitions, negative/positive, or moving graphic elements, depending on the angle or lighting.

Examples of possible schemes for anisotropic surface reliefs, which are schematic illustrations of microstructures reliefs in accordance with the invention, shown in Fig, 4.2 and 4.3. In each of these figures shows two anisotropic pixel of the surface topography 20/20', 21/21' and 22/22', respectively, of the anisotropy axis are rotated 90° relative to each other. The axis of anisotropy is directed vertically to the left of the pixel and horizontally to the right pixel. The elements of the anisotropic topography, shown in Fig, are elongated rectangular groove 23. The elements of the anisotropic topography, shown in Fig, are rectangular elevation 24 with rounded corners. The elements of the anisotropic topography, shown in Fig, are elongated linear grooves 25. Visually perceived light scatters or rejected mainly on thin grooves or elevations. Other schemes anisotropic surface reliefs in accordance with the invention can be found in the examples below.

For [daln] the further description of structures of this type in the present description is entered the value “aspect ratio of the surface topography (HARP), which is determined as the average ratio of length to width of the elements of the anisotropic surface relief. HARP largely determines the nature of light scattering in different azimuthal directions on the microstructure of the surface topography. For HOB=1, which corresponds to elements of the surface topography, the average size of which is equal to at least two transverse directions, the characteristics of the scattering of the incident light almost does not depend on the azimuth angle of light incidence. Therefore, the intensity of light reflected relief microstructures surface with HOB=1, almost does not change when you rotate the element containing such a relief microstructure surface, around an axis perpendicular to the surface of the element.

For anisotropic structures of the relief, i.e. HARP>1, the intensity of the reflected light depends on the azimuthal angle of the incident light. In order to capture the visual differences for different azimuthal angles of incidence of light, HARP exceed 1,1. To increase the visible contrast of the images obtained on the elements of the structures of the surface topography with different axes of anisotropy are preferred values HARP greater than 2. More preferred are values HARP greater than 5.

For very large values HARP range azimuth from the crystals, in which dissipates a substantial portion of the light becomes smaller, which makes it harder to perceive the light reflected from the image produced on the terrain surface. Therefore, the aim of the present invention is the provision of a parameter that can be used to develop structures of the surface topography so as to optimize characteristics of the light reflected from their surface, in terms of contrast and range of azimuthal angles of visibility. Therefore, in the preferred embodiment of the invention the value of HARP than 50, and more preferably the value of HARP does not exceed 20.

Moreover, it was found that the preferred options for relief microstructures surface in accordance with the invention can be characterized geometrically by using the selected appropriately characteristics depth and lateral dimensions of the surface topography. These characteristics will be described below. They can be defined for any real surface, preferably on the basis of the AFM images.

One such characteristic is associated with the fact that the surface topography is largely uncorrelated and, thus, is characterized by low length of the autocorrelation function.

Useful pairs is slow to characterize non-periodic and non-deterministic profile of the surface is the autocorrelation function and the corresponding length of the autocorrelation function. A one-dimensional or two-dimensional autocorrelation function of the surface profile can be understood as a measure of the predictability of the surface profile for two points spaced apart in the plane at distance X.

The autocorrelation function AC(x) the function P(x), such as the relief profile of the microstructure of the surface, is defined as follows:

You can read more about the autocorrelation function and the corresponding programming problems, for example, in the publication “Numerical methods in C: techniques of scientific computing, William X. Press, Saul A. Teukolsky, William T. Vetterling, Brian P. Flannery; Cambridge, new York: ed. Cambridge University Press, 1992. The use of the autocorrelation function for pattern recognition in image processing is considered, for example, in the publication “Digital image processing”, by William K. Pratt, new York, ed. “Wiley”, 2001.

For non-periodic or non-deterministic profile of the surface autocorrelation function quickly fades out with increasing x. On the other hand, for deterministic surface profiles, such as a diffraction grating, the autocorrelation function does not fade out. However, in the case of the diffraction grating autocorrelation function modulated by a periodic function. For almost a regular diffraction grating of ogiba is based on its autocorrelation function decays with increasing X.

Using one-dimensional autocorrelation function can be defined by a single characteristic number, the length L of autocorrelation. This is a shift for which the envelope of the autocorrelation function decays to a certain threshold. It was found that, for the purposes of the present invention is suitable threshold value equal to 10% of AC(x=0).

In order to set the autocorrelation length L, is determined by another parameter: the average distance P between the grooves. The length of the autocorrelation for microstructures in accordance with the present invention should be less than some value in units of R.

Thus, preferred options of relief microstructures surface in accordance with the invention are characterized by the fact that the terrain surface at least in one direction, which for anisotropic modulation of the surface is perpendicular to the anisotropy axis, has averaged autocorrelation function AC(x) with envelope, which decays to the level of 10% from the values of AC for x=0, within a certain length of autocorrelation, which is less than three times the average distance in transverse direction between adjacent transitions between the elevations and recesses.

More preferred are embossed microstructure of the surface, for which the autocorrelation length of men is above twice the average distance in transverse direction between adjacent transitions between the elevations and recesses. Even more preferred are embossed microstructure of the surface, for which the autocorrelation length of less than the average distance in transverse direction between adjacent transitions between the elevations and recesses.

In another preferred variant of the invention, the length L of the autocorrelation exceeds one hundredth of the value of the average distance in transverse direction between adjacent transitions between the elevations and recesses.

For microstructures anisotropic scattering surface topography in accordance with the invention, the axis of anisotropy can be determined, for example, on the basis of the corresponding AFM image or obtained on the basis of the autocorrelation function. Then you must calculate the one-dimensional autocorrelation function along lines perpendicular to the anisotropy axis, and then to produce averaged to obtain the averaged one-dimensional autocorrelation function. For this averaged one-dimensional autocorrelation function is determined by its envelope and the length L of autocorrelation.

The above definition of the geometric characteristics of embossed microstructures of the surface is illustrated in the following two examples. The first example relates to the microstructure of the surface topography to the surface of the hologram, well known in the art; with testwuide AFM image and the autocorrelation function is shown in Fig, 5.2 and 5.3. The second example relates to the microstructure of the surface relief in accordance with the invention; its corresponding AFM image and the autocorrelation function is shown in Fig, 6.2 and 6.3.

On Fig shows AFM image of the embossed microstructure surface to the surface of the hologram (the size of the surface area of 15 × 15 µm). On Fig see the two-dimensional autocorrelation function for AFM image Fig. It is obvious that the visible pattern of the diffraction grating violations of the AFM image is correlated to the entire image area and in all directions. The axis of anisotropy can be determined by AFM-image or two-dimensional autocorrelation function.

Averaged one-dimensional autocorrelation function (horizontal direction), calculated on lines perpendicular to the anisotropy axis, shown in Fig. The envelope of the autocorrelation function 30 marked on Fig dashed line 31. It is seen that for seven distances in the transverse direction between the grooves (the peaks of the autocorrelation function, shown in Fig, the envelope does not fall below 10% of the value of the autocorrelation function for the zero shift. Thus, the autocorrelation length, determined by the decay envelope to the level of 10%, for the surface of the hologram shown in Fig, C is acetelyne exceeds seven distances in the transverse direction between the grooves.

On Fig shows AFM image of the embossed microstructure of the surface in accordance with the invention (the size of the surface area of 15 × 15 μm), and Fig see the corresponding two-dimensional autocorrelation function. Fast decay of the autocorrelation function in the center Fig allows to conclude that the correlation of microstructure in accordance with the invention is very low.

On the AFM image shown in Fig, it is clear that the deepening of relief microstructure in accordance with the invention have the form of grooves, which run in the vertical direction. Thus, the axis of anisotropy vertical.

On Fig curve 34 represents the averaged one-dimensional autocorrelation function (in horizontal direction) relief microstructure surface Fig calculated on lines perpendicular to the anisotropy axis. In contrast to the microstructure described in the previous example, the one-dimensional autocorrelation function in this case falls sharply, and its envelope coincides with the function. Thus, the envelope quickly falls below 10%, and the corresponding autocorrelation length L does not exceed one transverse distance between the grooves.

Another feature of relief microstructures surface in accordance with the invention is the presence of two clearly what Araunah levels plateau topography. Their quality can be expressed in a quantitative form for the preferred embodiments of the invention based on the histogram of the heights (or depths) of the surface relief.

Ideally, proposed in the present invention, the element must be a system strictly with two levels of elevation, which consists of a flat elevations and recesses located at a certain distance from each other. Light scattered by such optical element will consist of two types of bundles of rays of scattered light: the light scattered on the hills, and the light scattered by the grooves. Between the two bundles of light rays will be interference, colour effects.

In reality, however, due to manufacturing processes arise desired and undesired irregularity and, thus, elevations and depressions, and also the distances between them are broken. Therefore, the histogram of the heights of the relief on the microstructure of the surface can be a good statistical tool for characterizing the surface topography and exhibiting the required plateau. The histogram can be obtained, for example, from the corresponding AFM images. Many modern software tools designed to perform mathematical calculations and image processing, contain the necessary m theme function.

Because relief microstructure surface in accordance with the invention retain two distinct plateau terrain, then the histogram should appear two distinct peaks. This is illustrated in Fig and 7.2.

On Fig shows the AFM image of the microstructure in accordance with the invention, already shown in figure 3, and Fig shows the corresponding histogram. It's clearly seen two distinct peak.

For quantitative evaluation of other characteristics of relief microstructures surface is introduced, the fill factor of the terrain. In the context of the present invention, the fill factor of the relief is defined as the ratio of the total area of the elevations to the total area of all of the elevations and recesses. To get good and excellent optical characteristics, it is preferable that the elevation and depressions have the same General area. In other words, elevation and deepening should balance each other, which means that the fill factor should be close to 0.5. This corresponds to a histogram with two peaks of equal size. For the microstructure shown in Fig, there is a small asymmetry of the histogram shown in Fig; the total area of the recesses is slightly less of the total area of the dais.

In General, the fill factor of the relief is La embossed microstructures surface in accordance with the invention may reside in a fairly wide range. Preferably, the fill factor of the relief is between 0.05 and 0.95 and more preferably between 0.2 and 0.8.

Most preferably, the fill factor of the terrain lies between 0.3 and 0.7, or between 0.4 and 0.6.

Next, to characterize distinct plateau surface topography can be a useful feature quality calculated based on the histogram of heights. Possible functions M quality has the following form: d

In the function M quality used dependence of the width of the peaks and the depth of modulation of the relief. The range of deviation of the elevations and recesses from their plateau lies in a given part of the modulation depth of the relief. Δx1and Δx2- the width of the two peaks of the histogram, measured at the level of 1/e from the full height of the peaks, where e is the base of natural logarithms (e≈2,72), and d is the distance between the two peaks, corresponding to the average distance in height between the plateau elevations and recesses or the depth of the relief. Δx1and Δx2and d shown in Fig.

Usually for the evaluation of such histogram of the heights of the selected width of the sample in the third dimension which is less than the value of d at least 50 times, preferably at least 100 times.

For the preferred options of relief microstructures surface in accordance with the invention, the function M quality Bo is the more 2. More preferably, the function M over 3.5.

For example, the microstructure Fig and 7.2 has the function M quality, equal to about 4.0.

In addition, the present invention relates to a method of manufacturing elements with the above-described relief microstructures of the surface.

In General, the method consists of two main stages. In the first stage receive a template with microstructure having the first and second zones of different transparency, and at least one transverse direction of the template for every 20 microns with at least one transition from the first zone to the second zone, or Vice versa, and the transverse location of the transitions is non-periodic.

In the second stage using the template on the surface of the resin or photoresist get microstructure, in which the elevation correspond to the first areas of the template and deepening correspond to the second areas of the template, and exaltation are mainly at the level of the upper plateau terrain, and deepening are mostly on the lower plateau of relief, so that the modulation depth of the relief was almost the same over the entire area of the surface.

As a rule, as a template using a metal template that can be used in exposure patterns, such as, for example, the process of photolithography or etching.

Usually, is in the type of the first and second zones of the template is fully transparent, for example the hole in the template, and the other type is opaque, for example, made of an opaque metal material pattern. However, experts know that depending on the specific exposure can also use the template with zones of different transparency (for example, halftone pattern).

The location is more transparent and less transparent areas of the photomask will be isotropic in the case of manufacturing microstructures isotropic surface topography and anisotropic in the case of manufacturing microstructures anisotropic surface relief.

In a preferred embodiment of the method of manufacturing a template in the first stage describes how to use the microstructure of the first and second zones of different transparency is obtained using technologies that are known in the art manufacturing topologically ordered corrugated surface structures.

One such technology is based on the separation of the phases and the stitching of the mixture stitched and massively materials. Topologically ordered corrugated surface structure can be obtained by preparing a mixture of at least two materials, of which at least one material is stitched, as at least one other material - massively, applying the mixture on a substrate, crosslinking at least the one part of the stitched material and removing at least a substantial part massivemocha material. For microstructures, which must be anisotropic, the stitching, the material can be maintained in the fusion process is in a certain condition, for example, using the underlying orientation layer or orienting the substrate surface.

More specifically, topologically ordered corrugated surface structure, suitable for the manufacture of a suitable template can be obtained as follows. In the first stage, a suitable substrate is applied a thin futureenergy film. Using linearly polarized UV radiation, for example, using one or more masks and repeated exposure (or one exposure with masks or polarization patterns, providing a structured irradiation at a single stage, or laser scanning and other), the hidden structure or image is recorded on this thin photoorientation film. A more detailed description of this technology photoorientation can be found, for example, in patent US 5389698. Exposed photopolymer has the ability to Orient a mixture of liquid crystals and stitched LCD prepolymers. In the second stage orienting the structured layer is covered with a mixture of stitched and massivemocha liquid crystal materials. Then this mixture liquid m the materials sewn, preferably by exposure of photochemically active radiation (UV radiation). When this occurs, the separation of the phases and the crosslinking liquid crystal prepolymer. Then massively material is removed, for example, using a suitable solvent, resulting in a gain of corrugated film with anisotropic surface structure. The basic principles of fabrication and optical properties of thin films with microallergen are described, for example, in international publications WO 01/29148 and WO 2004/027500. The content of these documents WO 01/29148 and WO 2004/027500 explicitly included in the description in the production of such corrugated thin films with anisotropic surface structure.

Films with topologically ordered grooved surface structures obtained, for example, using the described method, can be used for the manufacture of a microstructure of the template containing the first and second zones of different transparency. For this kind of film is applied to the material layer pattern, for example chromium. Then the film thickness is reduced, for example, using plasma etching, until removed material film in the lower zones of the corrugated surface will not be part of the underlying material of the template. After appearing pattern is removed, for example, by using wet etching.

Also magalismontanum and other technologies for the manufacture of the template, used in the proposed invention the method for manufacturing elements with relief microstructures of the surface.

In alternative embodiments, the above method of manufacturing a thin film microfilarial can be used, and other known technologies for micro - and nanostructures. For example, technology may be self-organizing in the copolymers or wypadanie.

You can also use a recording device with an electron beam. The beam diameter of such devices allows to obtain a very narrow area of exposure of the photoresist, and the positioning can be performed with precision of nanometers.

In addition, the electrolytic etching of metals or semiconductors, such as aluminum or silicon, also allows to obtain a porous micro - and nanostructure surfaces.

Below are some examples additionally illustrate the invention.

All of the examples using a metal template with microstructure, consisting of the first and second zones having different transparency. This template will receive the technology of photolithography or dry etching.

Example 1

On Fig-8.2 - illustrates the process of obtaining a template with microstructure containing first and second zones having different transparency, which is suitable for the proposed in ISO is reenie method of manufacturing elements with relief microstructures of the surface.

As the substrate using a glass or plastic plate 41, covered with a layer of metallization 42. For a metallization layer are preferably used metals such as aluminum, chromium or a similar metal, with a thickness of 10-50 nm.

On the layer 42 of the metallization layer is applied 43 with topologically ordered grooved surface structures (Fig). Film 43 receive in accordance with the method described above and disclosed in the documents WO 01/29148 and WO 2004/027500. The microstructure can be isotropic or anisotropic in different zones of the film. Using an ordered orientation of the structure, it is possible to record images, image composition, micro and similar objects on the corrugated surface of the film.

Then, the film 43 is subjected to plasma etching for the manifestation of part of the underlying film metallization (Fig). This operation may be performed using conventional oxygen plasma. In the result, the thickness of the film 43 is reduced to until the layer of metallization 42 is covered only partly by the material of the upper zones 43' of the original film 43.

At the next stage, partially manifested layer metallization 42 is subjected to wet etching using an appropriate etching solution (Fig). As a result, the layer 42 metallization appear structured ICRI the holes 44, corresponding to the lower areas of the corrugated surface of the film 43. Consequently, there is a template that can be used in the proposed invention the method of manufacturing elements with the above-described relief microstructures surface. If necessary, the remaining material 43' film 43 on the top of the remaining portion of a metallization layer may be removed, for example, using an oxygen plasma (Fig).

Example 2

On Fig-9.3 illustrates the use of the template with the microstructures obtained in Example 1 for the manufacture proposed in the invention of item, provided with a surface which creates the optical effect of relief microstructure surface.

Glass or plastic substrate 48 is covered with a layer 49 of positive photoresist (Fig). For this purpose very suitable, for example, photoresists series S1800 Shipley company. The thickness of the applied layer 49 photoresist defines the color that will eventually be obtained on the microstructure of the surface topography. Typical thickness of the layer of photoresist is in the range between 100 nm and 500 nm, but can be used and thicker layers. Depending on the type of photoresist may require thermal processing, such as holding for one minute on a hot plate at 110°C.

Then the prepared metal is ical pattern 42 with the generated microstructures on the plate 41 is pressed to the layer 49 of photoresist and exposed to a source 50 of UV radiation (Fig). As a light source can be used, the apparatus Bluepoint 2” development Dr. Henle (Honle) from Germany.

The exposure time is adjusted so that after processing, manifested a clear binary surface profile, i.e. a profile with two distinct plateau 51 and 52 of the relief (Fig).

It should be noted that instead of the positive photoresist in a similar process can also be used and a negative photoresist.

Using this technology were received proposed in the invention relief microstructure of the surface of good quality, and provides a high performance, since the metal pattern can be used repeatedly, and the photolithographic process, including the manifestation takes only a few minutes. The microstructure can be used as optical elements, but preferably they are used as a working matrix hardware replication.

To perform a qualitative comparison of topologically ordered the corrugated surface structure produced in accordance with known technology described, for example, in documents WO 01/29148 and WO 2004/027500, with the structure obtained in accordance with Example 2, was carried out the comparison of the optical properties of the above-described film 43, which is adequate topologically ordered corrugated surface structure, obtained in accordance with known technology, with the final product obtained in Example 2 (see Table).

Table
DescriptionFilm 43 (in accordance with the known method)Example 2 (in accordance with the invention)
Color saturationUsually colorless; for special structures possible weak pastel colorDeep rich color
Adjustability colorLimitedRegulated simply and efficiently
Color change in different zonesVery difficultMay
Image resolutionGoodGood

Example 3

Alternatively, the method described in Example 2, was tested and other possible technologies. Good results can be obtained by directly applying a layer of photoresist on the metal pattern on the walking film thickness.

On Fig again see the metal pattern 42 with microstructures on the plate 41, which is at this time covered with a layer 55 of the photoresist, as you can see in Fig. Exposure to UV radiation is performed through the rear wall of the substrate, on which the top there is a metal template with microstructures.

At the next stage, perform the manifestation of the photoresist, so it appears the microstructure. In this case, also when performing photolithographic process can be used in a positive or negative photoresist. On Fig shows the resulting layer 55 photoresist with microstructures on the positive photoresist, and Fig - on the negative photoresist.

Example 4

Below with reference to Fig and 11.2 describes another method of manufacturing proposed in the invention of item having a surface area to create the optical effect of relief microstructure surface.

Glass plate 59 that is used as a substrate, coated with a layer 60 of a material that can be etched, for example stitched prepolymer. Alternatively, you may use the substrate from a polymer, such as, for example, plexiglass, without additional coverage.

Then at the top of the substrate receive the metal pattern 61 microstructures in accordance with the method described in P is the iMER 1 (see Fig).

At the next stage, perform dry etching, so that the ions of the plasma was performed by etching through the openings in the metal pattern. This process is suitable oxygen plasma. The selectivity of the etching of the polymer and the metal is very high. Therefore, zone, covered with a very thin layer of metal, even of the order of several nanometers, will not be affected by oxygen plasma, and the result can be obtained micro - or nanographene. The duration of the etching process, the plasma determines the depth of the recesses and, accordingly, the color appearance of the resulting product. If the substrate is glass, it can also be used as the material, stopping the etching.

Finally, a metal pattern is removed by wet etching using a suitable solution for wet etching.

Example 5

As already mentioned, the proposed invention the elements that are parts of the surface to create the optical effect of the relief surface microstructures can be used as a working matrix for duplicating items. For example, this can be used by elements made in accordance with the methods described in Examples 1-4. After preparation item can be briefly immersed in a bath of wet etching for the Alenia remaining areas of the metal on the surface of the matrix.

The working matrix microstructures ready for manufacturing metal copies. This is accomplished by deposition of a thin layer of source metal, for example gold, silver or similar metal, and subsequent galvanic deposition of Nickel. After that, the Nickel working copy is used for the manufacture of duplicated copies by hot stamping a thin film of a suitable polymer or by photochemical crosslinking by UV radiation suitable material.

Further, the replicated copy of the microstructures can be covered with a layer of metallization (e.g., aluminum) to produce a well-reflecting surface. This is especially necessary in the case when such a replicated copy is used as a protective device.

Finally, the device may be protected by a dielectric passivating film or directly coated with an adhesive material suitable for the application of the product. In this case, the surface topography is filled with a dielectric material.

Reflecting device manufactured using the methods mentioned above, mainly characterized by monochrome reflection. Depending on the preparation of the tilt of the sample can sometimes be observed color changes. However, the property of such devices is the lack of R is durnyh of colours, that is a significant difference from the standard holograms.

Example 6

Of course, one element it is possible to combine two or more areas with different embossed microstructures surface. The elements of such a more complex type allows, for example, to create a multicolor image, and due to their complexity can also provide enhanced security.

On Fig-12.4 illustrates a variant of the method of manufacturing the element with the two sites have different relief microstructure surface.

On Fig presents a view of a glass or plastic substrate 65 with a layer of material that can be etched with foil 67 metallization with microstructures formed in accordance with the above-described method. Again, as in the previous examples, can be used glass or plastic plate with a suitable polymer coating or plate made of polymeric material, such as, for example, plexiglass.

After that, the prepared surface of the substrate subjected to the first plasma etching. The depth of etching defines a first visible color obtained on the finished product (Fig).

Then thus formed relief microstructure of the surface is covered with a layer 68 of positive photoresist and irradiated with UV specific area 69. Thereafter, the exposed photoresist is washed on site 69 in the development process (Fig).

Now, microstructure, already existing on the plot 68, may be additionally protrain on the second stage etching (Fig). Additional etching provides increased depth and determines the color of the microstructure on the section 68. Thus, the element is provided by two sections 69 and 70, which are creating various optical effects relief microstructure surface.

If necessary, described under cover of some sections and etching areas that remain uncoated, may be repeated to provide three or more sections with different microstructures.

Used templates can be made with pixels high resolution, the size of which can be much less than 10 microns. Thus, a suitable choice of colors and the arrangement of the pixels also gives your images on the basis of mixing complementary colors.

Example 7

Relief microstructure surface in accordance with the invention can also be made reflective or partially reflective. Appropriate samples are illustrated on Fig and 13.2.

To ensure reflection in a saturated color microstructure, usually covered with a thin layer 71 reflective material, t is whom, for example, aluminum, gold, chromium, etc. the Thickness of this film 71 determines the degree of reflection and transmission, which can be obtained devices with highly reflective or partially reflective.

Instead of partially reflecting metallic film layer 71 may also be coated with a high or low refractive index. Examples of materials with high refractive index are ZnS, ZnSe, ITO or TiO2. For this purpose, are also suitable composite materials containing nanoparticles of materials with high refractive index.

In alternative embodiments of the device with a partial reflection can also be obtained by only partially covering the microstructure of a material with a high refractive index, for example by applying the first coating to the entire surface of the microstructure, and then partially removing the coating, so that only part of the microstructures will be covered with reflective material. This is shown in Fig, where the layer 71 reflective material on some parts 72 missing.

Also on Fig and 13.2 shows protective and pestiviruses film 73, which can be used, for example, a transparent dielectric materials or materials with special characteristics absorption to further improve the appearance of the device in color.

the example 8

To demonstrate the optical properties of a relief microstructures surface in accordance with the invention Fig and 14.2 shows the reflectance spectra of one of the elements. The item was manufactured in accordance with the method described in Example 4 (etching through the metal template with microstructures), including coating with a thin aluminium film thickness of about 20 nm, and the measurement was carried out through the transparent piscivorous film with a refractive index of approximately 1.5.

Optical properties are best characterized by the color of the element in the scattering reflection, which in this case was green.

The characteristics of the different instances of the elements was evaluated by measuring the spectrum of the reflected light at different angles of incidence and observation (sensor position measuring device). For measurements were used photospectrometer Perkin Elmer Lambda 900 with an additional device Pela 1030, providing measurement of the spectrum of reflected light when adjusting the angular position of the sample and the angular position sensor. Typical spectra of reflected light was measured for the wavelength range 300-800 nm. When measuring any special polarizing device was not used. Exceptional lighting conditions are for the conditions under consideration mirror neg the supply, when the angle of reflection equals the angle of incidence or angle of the sensor is equal to twice the angle of the sample.

Spectra of light reflected from an element of the sample on Fig. The angle of incidence or angle of the sample (SA) is equal to 30°. Angle SA is the variance of the surface of the substrate from the plane perpendicular to the rays of the incident light, as shown in Fig in the sidebar on the left at the top. The angle sensor (DA) is the angle between the direction of incidence of light rays and the direction of the sensor, as also shown in the sidebar on the left at the top.

The spectra of the reflected light shows a distinct maximum at a wavelength of 525 nm, another maximum at a wavelength of 350 nm and a minimum at a wavelength of 400 nm. These distinct maxima and minima define good color saturation of the reflected light. Maximum reflectivity is achieved for angle detector equal to 40°, 20° less than the angle of specular reflection. For angles of the detector in the range from 30° to 50° noticeable decrease in the intensity of reflected light, and the shift of the wavelength, in this case, small.

A mirror reflection of light is different from the non-mirrored reflection. Specular reflection is manifested in the form of saturated purple color. The corresponding spectra of the reflected light shown in Fig. In the case of measurements for conditions of specular reflection angle DA sensor twice SA sample. Again on the chart you can see a distinct modulation, which almost corresponds to the complementary spectra of the diffuse reflection shown in Fig. This can be understood if we take into account that a large part of what is happening dispersion is shown in Fig. If there are no channels that are sensitive to scattering or absorption of the base color, then additional spectra can be left to mirror. Background approximately 4%corresponds to the achromatic reflection on protective pestiviruses layer of the device, which in this case consists of glass. As you can see in Fig, color spectra for conditions of specular reflection is also practically independent of the angle of inclination of the device.

Example 9

On Fig and Fig shows the spectra of the reflected light other pattern proposed in the invention of item. The item was manufactured in accordance with the method described in Example 4. The color of the scattered light orange.

On Fig the light angle or angle SA of the sample is equal to 30°. The spectra of the reflected light shows a distinct maximum at a wavelength of 583 nm, another maximum at a wavelength of 380 nm and a minimum at a wavelength of 453 nm. These maxima and minima determine the light orange color of the reflected light. Maximum reflectivity is achieved for DA corner detector, ravnos is 40°, that is 20° less than the angle of specular reflection. For sensor angle of 50°, a decrease in intensity of the reflected light, and a corresponding shift of the wavelength is approximately 30 nm.

The measurement results to mirror for the same sample cell shown in Fig. Again on the chart you can see a distinct modulation, which almost corresponds to the complement of the spectrum of the diffuse reflection shown in Fig. However, at least at a wavelength of 586 nm is not as pronounced, which means that the saturation of the reflected light is not very high. The color of the device is perceived visually as unsaturated blue.

1. A method of manufacturing an element having at least one portion of the surface to create the optical effect of relief microstructure surface, including:
- creation of a template having an anisotropic microstructure, containing the first and second areas of different transparency, and in the first transverse direction template for every 20 microns available, preferably on average at least one transition from the first zone to the second zone, or Vice versa, and in the second transverse direction of the pattern perpendicular to the first transverse direction, for every 200 microns has on average at least one transition from the first zone to the second zone, or Vice versa, and at first the m transverse direction transverse transitions is non-periodic;
- getting through the template relief microstructure in the surface of the resin or photoresist (49; 55; 60; 66) with the formation of prominences (13)corresponding to the first areas of the template, and recesses (14)corresponding to the second areas of the template, and exaltation (13) are at the level of the upper plateau (15; 51) relief, and the recesses (14) are at the level of the lower plateau (16; 52) of the relief, so that the modulation depth of the relief, essentially the same throughout the surface area.

2. The method according to claim 1, in which the microstructure of the first and second zones of different transparency template create by
- application layer (42) of the material of the template foil (43) with topologically ordered corrugated surface structure;
- reduction of the film thickness (43)until it is completely removed material film in the lower zones of the corrugated surface and will not open portion (44) of the underlying material of the template;
- remove the opened portions (44) of the template.

3. The method according to claim 2, in which topologically ordered corrugated surface structure is produced by preparing a mixture of at least two materials, of which at least one material is stitched, as at least one other material - massively, applying the mixture on the material layer pattern by stitching at least a significant part of the stitched material, udalenie least significant part massivemocha material.

4. The method according to any one of claims 1 to 3, intended for the manufacture of the element according to any one of claims 7 to 15.

5. The element obtained by the method according to any one of claims 1 to 3.

6. The element according to claim 5, characterized in that the relief structure surface is coated with the layer of metal.

7. Element having at least one portion of the surface to create the optical effect of relief microstructure (12) surface, and the relief microstructure has a modulation of the surface, consisting of transitions from elevations (13) to the recesses (14) and recesses (14) to the elevations (13), characterized in that in the first transverse direction of surface area for every 20 microns with at least one transition from exaltation (13) to the recess (14), or Vice versa, and in the second transverse direction of the surface perpendicular to the first transverse direction, for every 200 μm has on average at least one transition from exaltation to deepen or Vice versa, and:
at least in the first transverse direction transverse transitions is non-periodic,
- elevation (13) are at the level of the upper plateau (15; 51) relief, and the recesses (14) are at the level of the lower plateau (16; 52) of the relief, so that the modulation depth of the relief, essentially, the same surface area; and
- relief microst is ucture (12) the surface is anisotropic.

8. The element according to claim 7, characterized in that it has an aspect ratio of a surface topography that is greater than 1.1 and less than 50.

9. The element according to claim 7, characterized in that the embossed microstructure surface at least in a direction perpendicular to the anisotropy axis, has averaged one-dimensional autocorrelation function AC(x) with envelope (31), which decays to the level of 10% of the value of the AC at x=0, within a certain length (L) of the autocorrelation, and the length (L) of the autocorrelation is less than twice the average distance in transverse direction between adjacent transitions between elevations (13) and recesses (14).

10. The element according to claim 7, characterized in that it has a fill factor of the surface topography, which is in the range from 0.2 to 0.8.

11. The element according to claim 7, characterized in that the histogram of the heights on the relief microstructure surface has distinct first and second peaks, which can be determined by the quality function, with

where Δx1- the width of the first peak and Δx2- the width of the second peak, measured at the level of 1/e full height of the peak, and d is the distance between the two peaks, and the function M quality more than two.

12. The element according to claim 7, characterized in that it has a pattern of multiple areas of the surface to create the optical effect of relief m is crostructure surface.

13. Item by item 12, wherein the pattern includes at least two types of surface areas with anisotropic relief microstructures of the surface, which have different orientation directions of anisotropy.

14. Item by item 12, wherein the pattern includes at least two types of surface areas with relief microstructures of the surfaces that have different optical depth modulation.

15. Element according to any one of claims 7 to 14, characterized in that the relief structure surface is coated with the layer of metal.

16. A method of making copies relief microstructure surface using element according to any one of pp.5-15 as the master matrix.

17. Element having a relief microstructure of the surface obtained by the method according to item 16.

18. Protective device containing an element having at least one portion of the surface to create the optical effect of relief microstructure surface, and executed on any of pp.5-15 or 17.



 

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4 cl, 2 dwg

FIELD: optical engineering.

SUBSTANCE: method is based upon exposure of parts of light-sensitive medium by speckle pattern and subsequent processing of the medium. Exposed parts of light-sensitive medium have central and surrounding peripheral areas; the parts overlap each other with their peripheral areas. Exposure in central area is equal to preset value and exposure in peripheral area decreases linearly from preset value at its boundary with central area till zero at the boundary of exposed part. Shape, sizes and mutual disposition of exposed parts are chosen to provide constant exposition on whole surface of light-sensitive medium is constant and equals to preset value after process of exposure is finished. Indicatrix of diffusion is provided to be constant along the whole surface of speckle-diffuser at big sizes of speckle-diffuser.

EFFECT: improved efficiency.

3 cl, 6 dwg

Reflective coating // 2063056
The invention relates to the field of lighting and can be used to create reflective surfaces, lights lasers, where high reflectivity as UV radiation and IR radiation, the radiation resistance and mechanical strength of the coating

FIELD: optical engineering.

SUBSTANCE: method is based upon exposure of parts of light-sensitive medium by speckle pattern and subsequent processing of the medium. Exposed parts of light-sensitive medium have central and surrounding peripheral areas; the parts overlap each other with their peripheral areas. Exposure in central area is equal to preset value and exposure in peripheral area decreases linearly from preset value at its boundary with central area till zero at the boundary of exposed part. Shape, sizes and mutual disposition of exposed parts are chosen to provide constant exposition on whole surface of light-sensitive medium is constant and equals to preset value after process of exposure is finished. Indicatrix of diffusion is provided to be constant along the whole surface of speckle-diffuser at big sizes of speckle-diffuser.

EFFECT: improved efficiency.

3 cl, 6 dwg

FIELD: radiation shielding and masking systems, those producing illumination effects (advertisement, decorative lights), data display systems.

SUBSTANCE: proposed device that can be used for dissipating electromagnetic radiation, such as light, radio waves, X-rays, as well as for dissipating particle streams is, essentially, multilayer screen some of whose layers are deformable ones. Electric field is built up between two electricity conducting layers due to voltage applied to these layers. In the process conducting layers are split into segments and separate electrodes are brought to respective layers. Voltage applied to separate segments permanently varies with the result that electric field produced is nonuniform and deformable layers are embossed due to nonuniformity of attractive forces between electrodes, this embossed pattern permanently changing its configuration. Radiation (light of different ranges, radio and electromagnetic waves, particle streams) passed through screen or reflected therefrom dissipate due to optical nonuniformity. Kind of dissipation continuously varies due to changes in embossed pattern. Segments of conducting layers can be energized obeying different laws including pseudorandom one.

EFFECT: reduced specific surface power of incident radiation.

4 cl, 2 dwg

FIELD: optics.

SUBSTANCE: micro-lens array includes micro-lens array of Fresnel lenses, provided with grooves, divided on reflecting and deflecting parts. Reflecting surface is engineering so that angle of light fall onto it exceeds angle of full inner reflection, and limit angle is computed from formula , and functional dependence between input and output beams and micro-lens parameters is described by formula , where α - input angle; β - output angle; γ - angle of inclination of reflecting surface; δ - maximal falling angle of light; ε - angle of inclination of deflecting surface; n1 - air deflection coefficient; n2 - lens material deflection coefficient. Output beam is formed in such a way, that central groove forms wide-angle zone, and next grooves from center to edge form a zone from edge to center.

EFFECT: increased beam divergence angle after micro-structured optics up to 170-180° (depending on source used) with efficiency of 80-90% and with fully controlled shape of output beam.

14 dwg

FIELD: physics.

SUBSTANCE: optical substrate contains three-dimensional surface preset by the first function of surface pattern, modulated second function of surface pattern. The first function of surface pattern can be described by length, width and vertex angle with optical characteristics for formation of, at least, one output mirror component. The second function of surface pattern can be described by geometry with, at least, pseudorandom characteristic for modulation of the first function of surface pattern, at least, by phase along length of the first function of surface pattern. At that the phase presents horizontal position of peak along width. The surface of optical substrate creates mirror and scattered light from input light beam. The three-dimensional surface can have value of correlation function which is less than approximately 37 percent of initial throughout the length of correlation about 1 cm or less.

EFFECT: brightness increase is provided.

46 cl, 41 dwg

FIELD: physics.

SUBSTANCE: relief microstructure of the surface has protrusions and depressions, where in the first cross direction of an area of the surface there is an average of at least one transition from a protrusion to a depression or vice versa in every 20 mcm, and in the second cross direction of a pattern which is perpendicular to the first direction, there is an average of at least one transition from a first zone to a second zone or vice versa in every 200 mcm. The microstructure is characterised by that in the first direction the lateral arrangement of transitions is non-periodic and that protrusions mainly lie in the same top relief plateau and the depressions mainly lie in the same bottom relief plateau. Due to scattering effects, the surface relief microstructures are suitable for displaying images with a sharp transition between negative and positive images.

EFFECT: well distinguished and saturated image colours and absence of rainbow colours.

18 cl, 39 dwg

FIELD: physics.

SUBSTANCE: liquid reservoir has a transparent wall and a microrelief layer, having a microrelief structure and lying on the outer surface of the wall, and a protective layer covering the microrelief structure, arranged in order from the wall. The protective layer has refraction index which is essentially equal to that of the liquid to be stored in the reservoir.

EFFECT: reduced reflection from the surface of the reservoir and longevity.

22 cl, 19 dwg

Optical element // 2451311

FIELD: physics.

SUBSTANCE: optical element has a base and primary and secondary structures lying on the surface of the base and representing a protrusion or depression. The primary structures are arranged in form of a plurality of rows of tracks on the surface of the base with spacing equal to or less than the wavelength of visible light. The secondary structures are smaller than the primary structures. Other versions of the optical element are possible. The secondary structures can be made between the primary structures and on adjacent areas, and the primary structures are connected to each other by the secondary structures. The spatial frequency of the secondary structures is higher than the frequency obtained based on the period of arrangement of the primary structures. The primary structures are made periodically in the configuration a hexagonal or quasi-hexagonal array or a tetragonal or quasi-tetragonal array and lie along the orientation of the corresponding symmetry. The secondary structures can be arranged on surfaces of the primary structures. The lower parts of adjacent structures can overlap each other.

EFFECT: improved antireflection characteristic and high technological effectiveness.

21 cl, 56 dwg, 1 tbl

FIELD: electricity.

SUBSTANCE: method for manufacture of the element produced by way of micro-treatment includes the following stages: generation of a resist layer on the stamping mould, exposure and development of the layer generated on the stamping mould for formation of a structure within the resist layer, placement of the stamping mould with a structure created in the resist layer onto an electrode and the stamp mould etching for an uneven shape formation on the stamping mould surface to obtain an element produced by way of micro-treatment. An uneven shape is formed on the electrode surface so that at the etching stage anisotropic etching is performed in a direction slanted relative to the stamping mould surface. The etching device contains a reservoir for the etching reaction and the first and the second electrodes positioned on opposite sides in the reservoir. The first electrode has an accommodation surface for accommodation of the substrate having an uneven surface shape so that anisotropic etching is performed in a direction slanted relative to the substrate surface.

EFFECT: provision for manufacture of an element having uneven structures slanted relative to the normal and the substrate surface at least in two different directions or having multiple areas wherein the structures slanting direction may be varied.

9 cl, 59 dwg

FIELD: physics.

SUBSTANCE: optical film has a base with convex structural components which are two-dimensionally and orderly formed directly on its surface, and a solid coating layer on the surface of the base, having said structural components. The surface of the solid coating layer has a continuous wavelike shape which matches the shape of structural components of the surface of the base. The maximum amplitude (A) and minimum wavelength (λ) of the continuous wavelike surface are essentially constant, and the ratio (A/λ) of the maximum amplitude (A) to the minimum wavelength (λ) is greater than 0.002 but not greater than 0.011. The film has full light transmission factor of 92% or higher, dullness of 1.5% or less, internal dullness of 0.5% or less and opacity of 0.7% or less.

EFFECT: improved anti-glare properties and contrast.

18 cl, 22 dwg

FIELD: physics.

SUBSTANCE: optical element has a base and a large number of structures lying on the surface of the base. The structures are protrusions or depressions and lie with spacing which is less than or equal to the wavelength of light under conditions of use. The effective refraction index in the direction of the depth of the structures gradually increases towards the base, and the curve of the effective refraction index has two more points of inflexion. The structures can be arranged in form of a hexagonal array, a quasi-hexagonal array, a quadrilateral array or a quasi-quadrilateral array. The structures have two or more steps between the peak and the bottom part of the structures and have a peak and/or a bottom part; or the structures have a curvilinear surface and become wider from the peak to the bottom part; or change in the effective refraction index in the direction of the depth of the structures on the upper side of the structures is greater than the average value of the effective refraction index on the slope of the structure; or change in effective refraction index in the direction of the depth of the structures on the side of the base of the structures is greater than the average value of the effective refraction index on the slop of the structure.

EFFECT: improved antireflection properties of optical elements.

30 cl, 93 dwg

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