The diffraction structure

 

(57) Abstract:

The diffraction structure includes a substrate, first and second rows of faces that are at an angle to the substrate plane. On each face formed of a diffraction grating with a period of not more than 500 nm. The length of the bases of the faces is in the range from 1 to 100 μm, and the depression of the diffraction grating is in the range from 0.1 μm to half the size of the face. The period of the diffraction grating is less than the wavelength corresponding to perceive color, and the opposite face is arranged to capture light with a shorter wavelength. The diffraction structure is obtained by formation of the machining lines on the surface of the faces, or by applying electron or ion beam on the protective layer located on a form obtained by anisotropic etching of the silicon substrate. Provides the color in a wide range of angles and lighting. 3 S. and 8 C.p. f-crystals, 11 ill.

The present invention relates to diffractive structure.

To apply in many cases it is desirable to have a diffraction structure reflecting properties which do not depend on a specific, limited lighting and angles when creating C obtained by thermoforming, with reflective aluminum foil, placed on a layer obtained by thermoforming. The hologram is formed by the surface topography. The absence of absorption in the structure and sensitivity of the holographic image to the angle of view leads to the fact that when diffused light (such as dim fluorescent light or light in the room, lit by many lamps), a hologram cannot be seen or can be seen only within a very narrow range of angles.

An additional example is that the diffraction pigments, such as described in JP-A-63/172779, helps the application of diffraction patterns, and they will not look "washed out" and colorless under normal review outdoors. In JP-A-63/172779 described pigment, which consists of many particles, each of which has on its surface grooves, which form a diffraction grating. Because of the lattice on the particles experience strong dependence on the angle of view and have no internal absorption, color effect of diffraction will be visible only when a strong, intense directional light, such as direct sunlight or illumination light. When scattered light (for example, on a cloudy day) pigment, is based on a lot located on the periodic intervals of step structures, each of which is placed deeply in the environment.

The present invention is the task of education diffraction patterns that will create color in a wide range of angles and lighting.

In accordance with the first aspect of the present invention provides a diffractive structure, and the structure contains: essentially flat substrate; and the number of faces formed in or on the substrate, the plane or planes in which lie the faces that are at an angle other than zero to the substrate plane, and the faces of the formed diffraction grating having a period of 500 nm or less.

In accordance with the second aspect of the present invention provides a method of manufacturing the diffraction patterns, as described above, and the method comprises the stage of: (A) produce the shape by mechanical processing of the substrate by repeated passes of the cutting tool, and the tool cuts the substrate more deeply with each pass of the tool, so as to create a cutting surface, on which there are lines of mechanical processing; (B) repeat stage (A) in order to receive the additional cutting powerheat to create the groove, on each of the opposite surfaces of which are mechanical finishing; (C) produce a template from the specified form; and (D) produce a diffraction structure from the specified template, and each face is formed of a diffraction grating corresponding to the machining lines on the grooves of the form.

In accordance with a third aspect of the present invention provides a method of manufacturing the diffraction patterns, as described above, and the method comprises the following stages: (A) produce a form by anisotropic etching of the silicon substrate for the production of many faces in the form; (B) cover the form of the acid-resistant layer; (C) cause the fine structure of the diffraction grating directly on the acid-resistant layer by an electron beam or ion beam; (D) produce a template from the specified form; and (E) produce a diffraction structure from the specified template.

Preferred features of the present invention set forth in the following claims.

So, in the example of the invention, the structure with a prismatic surface, consisting of a number of essentially planar faces formed in the polymer layer. These faces are usually . the again with the grooves, the number of correct quadrilaterals, pyramids, the bases of which are square or angular cubic structures (in which all the faces are squares) are examples of such prismatic structure. The diffraction structure is formed on the surface of each face. This smaller structure can be a (not restrictive) the number of grooves, crossed bars, or 2-dimensional series of troughs and peaks, such as the well-known structure "compound eyes". A smaller structure usually has a size in the range of half the size of faces to 0.1 microns. This structure should preferably be covered with metal, so that it absorbs light at certain angles of incidence, but has strong diffraction at different angles.

The invention provides a diffraction structure, which creates a color in a wide range of angles and lighting. The diffraction structure can be manufactured by a simple method using a conventional film-forming plastics.

The structural design of the present invention will be described by means of examples with reference to the accompanying drawings, on which:

Fig. 1 depicts schematics perspectivny view of another example of the diffraction structure in accordance with the present invention;

Fig. 3 is a schematic perspective view of an additional example of the diffraction structure in accordance with the present invention;

Fig. 4 is a schematic perspective slit diffraction patterns, filled polymer;

Fig. 5 is a diagram representing the fall of the light beam on the diffraction structure;

Fig. 6 - decomposition of a ray of light falling on the surface of a polymer layer diffraction patterns;

Fig. 7 - decomposition of a ray of light incident on the polymer layer diffraction patterns;

Fig. 8 - decomposition of a ray of light incident on the diffraction grating structure;

Fig. 9 - decomposition of light rays deviated by the diffraction grating structure;

Fig. 10 - decomposition of the rays of light leaving the diffraction structure; and

Fig. 11 - map of colors on the CIE (international Commission on illumination), showing how changes in the perceived color change angle of view.

In Fig. 1 shows the diffraction structure 100 formed by the substrate 1, having a number of faces 2. Face 2 in this example is formed of triangular faces 2 rows of 3 pyramids, the bases of which are squares. Pyramid 3 formed in or on the substrate 1, and their Foundation in the form of Quadra is on each side of the base square 4 3 pyramids can be in the range from 1 μm to 100 μm. On each face 2 of the 3 pyramids has a diffraction structure of the correct type diffraction grating 5 is formed by grooves or lines 6, between which there are regular intervals. Diffraction grating 5 in this example has a period of 300 nm (i.e., the interval between successive lines 6 300 nm) height (i.e., depth of lines 6) of about 100 nm.

Instead of the 3 pyramids, the bases of which are squares that can be formed two-dimensional faces 2 as the faces of the pyramids, the bases of which are right triangles tetrahedra (see Fig. 2), the angular cubic structures (in which all or substantially all of the faces are squares), or any other polyhedra or structures, which form a series of identical or essentially identical faces that protrude from the plane of the substrate 1 at an angle from 0 to 90oto the plane of the substrate 1.

Instead of a diffraction grating, which is applied to the line, as described above, can be used as the diffraction grating 5 2-dimensional series of depressions and protrusions, such as the known structure "compound eyes", shown in Fig. 3.

Generally speaking, the length of the bases of the sides 2 may be in the range from 1 siteline half the size of the faces, provided that the maximum is 0.5 μm.

Since the diffraction grating structure 5 is at an angle to the normal to the substrate 1, can be used diffraction gratings less than the wavelength that provides the minimum variance (i.e. such minimal color change with angle changes as soon as possible) and excludes some colors that cannot be reflected because the length of their waves too big.

Moreover, the opposite face 2 can pick up the color with a shorter wavelength, because they are deflected at a large angle with respect to faces than color with a shorter wavelength.

Thus, in a preferred design, there are two mechanisms for color separation. Dazzling color effects can be obtained even with diffused lighting and without the use of pigments or dyes.

Two-dimensional patterns of faces, as described, such as the faces of the rows of pyramids or tetrahedra, lower the sensitivity of the diffraction patterns 100 to rotate the structure 100 as in its own plane, and from its plane, which is observed in the structures with the same faces. Thus, as will be paysandisia lighting conditions and angles.

The use of the structure with a V-shaped groove (i.e. one-dimensional) faces of 2 means that the color effect will depend on the angle of rotation of the substrate in its plane, although the relative immunity of the structure to the rotation of its plane is still in place.

An example of a process of manufacturing the diffractive structure 100 of the present invention will be described below.

First, non-ferrous metal, such as brass or copper, is treated mechanically by using a very sharp diamond cutter (not shown) to form a shape that is essentially identical to the diffraction structure 100, which must be received at the end. Diamond tip cutter may have an angle at the top of the 30o. The cutter is used to cut the groove on the first depth, to create a cutting surface having a length equal to the step formed by the diffraction grating. Then the cutter is used to cut the groove to the second depth and penetrate the surface to a length which is twice as many steps of the diffraction grating. This process is repeated as long as the groove is not cut to a predetermined depth, and the cutter is moved deeper into the material form of narisetti, with each successive pass of the cutter. As a result of these successive deeper passes machining cutter, the structure of the diffraction grating, consisting of lines, is formed of the usual signs of mechanical processing, obtained during successive passes of the cutter. Groove cut thus forms the first row of faces in the material. The opposite number of faces 2' and other numbers of faces, both parallel and perpendicular to the first row of faces produced by additional machining grooves in a similar way, with additional grooves parallel and perpendicular to the first groove. The angle at the top between the opposite faces may be, for example, 90oalthough this will depend on the geometry and height of the 3 pyramids, tetrahedra or other polyhedra that form faces 2.

To increase the speed of manufacture can be used a number of similar cutting tools for cutting parallel rows of grooves education faces a coupled way. Perpendicular rows can be cut by moving the same or different set of cutting tools perpendicular to the first row Gras is evidence which are squares, pyramids, the bases of which are triangles, regular tetrahedra, corner cube structures or other polyhedra or structures, is produced by anisotropic etching of silicon. It provides a very flat surface faces 2. The form is then covered with acid-resistant layer. Fine structure, which forms a diffraction grating 5, and then directly applied on the acid-resistant layer by an electron beam or ion beam.

Whichever way the form was not established, the form is then processed by electroplating for the formation of the hard template, which is a negative form, and, consequently, also the negative formed by the diffractive structure 100. The material of the template must be rigid enough to be able to squeeze relief from plastic material or other material from which is formed a diffractive structure 100. The template can be, for example, of Nickel or copper.

The template is then subjected to thermoforming to obtain a negative duplicate of the template from the polymer, in the same way as a normal commercial hologram. Appropriate polymers include polymethyl methacrylate or poly, to obtain diffraction patterns 100, shown in Fig. 1. The metal layer may have a thickness of from 10 to 50 nm and preferably is intermittent, covering small-scale relief, which forms a diffraction grating 5, so that the diffraction grating 5 is a partially absorptive or transmissive and has only a weak mirror.

The structure 100 is preferably then fill with a layer of material 7. Material layer 7 is transparent and may be a dry solution or chemically cured polymer, so that the structure 100 is essentially flat and parallel outer surfaces and the inner relief structure filled with polymer 7 as shown in Fig. 2. The polymer layer 7 typically can be an adhesive that is used for fixation of the diffraction structure 100 to the substrate on which it is mounted.

The light that enters the polymer layer 7 is subjected to diffraction, is absorbed or reflected by the faces 2. Not affected by the diffraction of the light is absorbed by the diffraction grating 5 or mirrored. If it is mirrored, it passes on the adjacent face 2, where he again either absorbed or mirrored. If diffractio 1% can come back after two such reflections. If diffraction is absent, the entire structure 100 is therefore essentially non-reflective and it seems the black audience. Diffraction grating 5 can be designed to reduce the amount of light that is mirrored, which provides that the grating spacing was less than the wavelength of light incident on the grating, and the depth of the grating 5 was such that the reverse reflection was extinguished as a result of interference. If the surface of the grating is covered, as above, dim metal (i.e., a metal with low reflectivity, such as copper, Nickel or aluminum) or metal is discontinuous in a direction across the lines 6 grating 5, the incident light rather absorbed than reflected.

Diffraction occurs when the wavelength of the incident light, the angle of incidence of light and the period of the diffraction grating are connected in the following ratio:

/ = dsin()+dsin(),

where is the wavelength of light, the refractive index of the polymer 7, the filling of the diffraction structure, and the angles of incidence and diffraction, respectively, relative to the normal 8 to the face 2, and d is the period of the diffraction grating 5, as shown in Fig. 5.

The perceived color from the structure 100 can be calculated by buil is but how does the distribution of rays as the first rays refracted on the surface of the polymer when they are included in the polymer, and then subjected to diffraction on the edge and again refracted when the rays emerge from the polymer.

In Fig. 6 shows a polar diagram of the intensity falling on a surface with diffused lighting, and surface in this case is the outer surface of a polymer layer 7. The intensity decreases depending on the cosine of the angle of incidence. This dependence is known as the lighting on Lambert.

Due to refraction at the boundary of air and polymer 9 the range of angles at which light rays are distributed inside the polymer layer 7 is reduced, as shown in the polar diagram in Fig. 7.

As shown in Fig. 8, the rays then strike the diffraction grating 5 on the surfaces of the sides 2 in a certain range of angles and rays undergoes diffraction. To simplify this description, it is assumed that (i) when the diffraction potential, all the light undergoes diffraction, and (ii) if the diffraction impossible, the light is absorbed or passed diffraction grating 5 as described above. You must understand, however, that in practice the effectiveness of d through the diffraction grating 5 on specific faces 2, shielded by the adjacent face 2 and does not leave the diffractive structure 100. Polar diagram of Fig. 9 shows the distribution of affected diffraction rays from one side of 2 x-ray diffraction system 100 for three different wavelengths. These wavelengths correspond to the peaks of the sensitivity of the visible colors. The solid line represents blue, dotted line denotes a green color and a dashed line denotes a red color.

As the rays leave the polymer layer 7, it is again refracted at the boundary of air and polymer 9. In Fig. 10 shows the distribution of the rays leaving the diffractive structure 100, which was subjected to diffraction by one face 2.

The light rays leaving one face 2 can be added to the rays from the adjacent edges 2 in order to form a graph on a standard map colors CIE (International Commission on illumination), which shows the change in the perceived color change angle of view. The map shown in Fig. 11. When the range of the angle of view exceeds 80o(40oto the normal to the surface of a polymer layer 9), deviations from the perceived color is very small. In this case, the diffractive structure 100 generates a yellow color when Russian the fractional grating 5 can be created in various colors.

Thus, the present invention generates a color diffractive structure 100 that supports intense color when observed in scattered light in a wide range of angles.

The structure 100 may be fabricated using conventional prevailing technology on a large surface and can be formed in a continuous polymer film through a one-stage process of extrusion of relief, similar to that used in the production of holograms.

The color in the first place depends on the angle of the faces and pitch of the diffraction grating, and neither the one nor the other does not change significantly during wear. Diffractive structure 100 is therefore ideal for the production of large amounts of material. Diffractive structure 100 is specifically applied in safety films on, for example, credit or debit cards that require a lot of essentially identical diffraction structures 100.

Embodiment of the present invention has been described with specific references to examples. However, it is necessary to take into account that in the described examples may be made variations and modifications within the range of infusion of the faces, formed in or on the substrate, the plane or planes in which lie the faces are at an angle other than zero to the substrate plane; a second row of faces, which lie essentially in a second plane or planes which are at an angle to the first row of facets and the plane of the substrate, so that the faces of the first and second series being located opposite each other, and on each face formed of a diffraction grating, wherein the diffraction grating has a period of not more than 500 nm, and the length of the bases of the faces is in the range from 1 to 100 μm, trench grating is in the range from 0.1 μm to half the size of the faces, provided that the maximum is 0.5 μm, using a diffraction grating with a period less than a wavelength corresponding to perceive color, and the opposite face is arranged to capture light with a shorter wavelength.

2. A method of manufacturing the diffraction patterns, which are made form by processing the substrate, which receives the first surface and opposite her additional surface forming the groove, make sablo the Ani, located at an angle to the surface of the substrate, and each of these faces is formed of a diffraction grating, characterized in that in the manufacture of forms in the first stage (A) process the substrate through mechanical processing by repeated passes of the cutting tool, and the tool cuts the substrate more deeply with each pass of the tool, forming a first cutting surface, on which there are lines of mechanical processing, in the second stage (B) repeat stage (A), forming an additional surface on which there are lines of mechanical processing, and formed on the sides of the diffraction grating corresponds to the machining lines on the surfaces forming the groove.

3. The method according to p. 2, characterized in that the additional cut grooves located in a line parallel to the first grooves located in a line that cut through repetitive steps (a) and (B).

4. The method according to p. 2 or 3, characterized in that the additional grooves located in a line perpendicular to the first groove located in a line, cut through repetitive steps (a) and (B).

5. The method according to p. 2, characterized in that cut simultaneously with the first groove, located in a line through a series of paired cutting tools.

6. The method according to p. 2 or 5, characterized in that the additional grooves located in a line perpendicular to the first groove located in the line simultaneously cut through a series of paired cutting tools.

7. A method of manufacturing the diffraction patterns, which produce a form that contains many facets, produce a template using the specified form, using the specified template to produce a diffraction structure, characterized in that in the manufacture of forms containing faces, carry out anisotropic etching of the silicon substrate, cover form a protective layer and cause the fine structure of the diffraction grating directly on the protective layer by an electron beam or ion beam.

8. The method according to any of paragraphs.2 to 7, characterized in that the template is manufactured by processing forms electroformed.

9. The method according to any of paragraphs.2 to 8, characterized in that the diffraction structure is manufactured by thermoforming template.

10. The method according to p. 9, characterized in that the faces of the diffraction patterns is covered with a layer of metal.

11. The method according to

 

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Multicolor applique // 2055498

FIELD: manufacture of multi-layered films with optical effects, and also decorative products, covered in multi-layered film.

SUBSTANCE: multi-layered film for manufacture of decorated product, which contains a base decorated by multi-layered film with curved sections of surface, represents IMD-film or film, usable for deep stretching, which is made with possible deformation during manufacture of decorated product to match the curvature of base of decorated product. The IMD-film or deep stretching-compatible film contains a transparent structural layer with spatial structure which creates a visually perceptible effect and a deflecting layer, positioned in direction of viewing under the structural layer. The decorated product, in particular, Handy-cover or Handy-window, contains a base with curved sections of surface and at least one decorative element, positioned in the area of one or several curvatures of base surface. The decorative element is composed of multi-layered film, which during manufacture of the base is deformed to match one or several curvatures.

EFFECT: possible creation of stable image without distortions, on sections, where the base has curvatures of surface.

3 cl, 8 dwg

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