CS201940B1 - Method of creating the line figures on the light-sensitive materials - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a method for producing line patterns on light-sensitive materials by light wave interference.

In many cases, it is necessary to create a line pattern with a certain geometry and prescribed spatial frequency scaling on the photographic material or other radiation-sensitive material. This problem often occurs when measuring and evaluating the ability of photographic materials, optical instruments, etc. to reproduce fine structures, especially when measuring the resolution and modulation transfer function.

For this, a method that uses interference of plane and spherical light waves according to MS. Certificate No. 189.882. A certain disadvantage of this method, however, is the need to realize a plane (light wave). For this purpose, an arrangement is used in which the coherent optical radiation beam is concentrated at one point and the spherical wave thus formed becomes plane.

This disadvantage is overcome by the method of forming line patterns on the photosensitive materials of the invention. Its essence is the creation of line patterns by interference of two spherical light waves on a light-sensitive layer, which is inserted into the interference field.

The light-sensitive layer is preferably deposited on the surface of a rotating hyperboloid, the focal points of which lie in the intersection of the light rays incident on the light-sensitive layer from the individual light waves.

The light-sensitive layer can also advantageously be deposited on the surface of a perpendicular hyperbolic cylinder, wherein the foci of the hyperboles lie on lines passing through the intersections of the light rays striking the light-sensitive layer from the individual light waves.

The light-sensitive layer also preferably forms a tangent plane to the rotary hyperboloid, or is deposited on the surface of a circular cylindrical surface approximating the surface of the hyperbolic cylinder, or forms a tangent plane to the hyperbolic cylinder.

In the method according to the invention, there is no need to transform the already formed spherical wave into a plane wave.

Another advantage is that, in this case, there is another possibility to influence the configuration of the shapes compared to the old way. The distribution of the extremes of the interference field at a given wavelength of radiation is dependent on the distance of the sensitive layer from the spherical wave source in the case of plane and spherical wave interference, and when the two spherical waves interfere with each other.

Thus, the two-wave interference method simplifies the apparatus while extending its capabilities.

The geometry of the pattern recorded on the irradiated material depends on how the sensitive layer is deposited in the interference field.

It is often necessary that the exposed radiation reach the surface of the sensitive layer perpendicularly. This can be achieved by having the sensitive layer in the form of a rotating hyperboloid whose foci lie in the centers of the spherical waves.

When implementing a light-wave interference device, it is usually necessary for the light beam between the radiation sources and the sensitive layer to be deflected by mirrors, etc. The way the sensitive layer is deposited spherical light waves, not the position of real spherical wave sources.

Said mounting method cannot be used for sensitive layers deposited on substrates which cannot follow the shape of the undevelopable area, i.e. for the vast majority of photographic materials. In such a case, favorable results can be obtained by placing the layer on the surface of a hyperbolic cylinder whose hyperboles have foci on lines passing through the centers of the spherical waves, then the radiation impinges on the sensitive layer exactly perpendicular to the curve and approximately perpendicular to the band around it.

This implies some limitations on the width of the usable record, but this is not a malfunction for the resolvometric measurement.

It is usually sufficient to deposit a sensitive layer on the surface of a circular cylinder which approximates said hyperbolic cylinder; a circular cylinder is easier to manufacture than hyperbolic.

Car patterns with low spatial frequencies can be recorded with good results even when the sensitive layer is positioned in a plane perpendicular to the line of both radiation sources.

Sensitive layers deposited on a rigid item, such as photographic plates or metallic or semiconductor materials coated with light-sensitive photoresist varnishes, should be positioned so that the layer touches the surface of the intended rotational surface when exposed. perboloid at a location in the field of spatial frequencies that are most relevant to the application. Records of a wide range of pros-

Claims (6)

SUBJECT A method for producing line patterns on photosensitive materials, characterized in that the patterns are formed by the interference of two spherical light waves on a photosensitive layer embedded in an interference field. 2. Method according to claim 1, characterized in that the photosensitive layer is deposited on the surface of a rotating hyperboloid, the foci of which lie in the intersection of the light rays striking the photosensitive layer from the individual light waves. 3. The method of claim 1, wherein the photosensitive layer is deposited on the surface of a perpendicular hyperbolic cylinder, wherein foci of torque frequencies are then formed by successively exposing the necessary number of samples at different positions. One example of a method of creating line patterns according to the invention is shown in Fig. 1. The light rays emerging from the laser 1 are separated by a semipermeable first mirror 2 and two beams. One of the beams passes through the semipermeable first mirror 2 and concentrates with the first lens 6 at the first point 8. The second beam is reflected on the semipermeable first mirror 2, and after reflection on the second mirror 3 is centered by the second lens 7 at the second point 9. 9, the actual sources of spherical light waves lie. The wave coming from the second point 9 impinges on the irradiated sensitive layer deposited on the surface 10 of the passage through the semipermeable third mirror 5; the second wave impinges on the sensitive layer after reflection on the fourth mirror 4 and the semipermeable mirror 5. In this case, the foci of the surface 10 lie in the real radiation source formed by the second point 9 and the virtual source 11. The method of depositing the sensitive layer according to the invention can be realized, for example, by depositing a sensitive material - a photographic film - in the body of the camera with a slit lens with the lens removed in the interference field generated in the space behind the semipermeable third mirror 5. The film path without modification allows to expose the film stored on the plane, other mechanisms of the device are used to feed and measure the film. To expose the film deposited on the surface of the circular or hyperbolic cylinder, the film path is completed with a film guide insert over the appropriate area. The film extends between two cylindrical surfaces, the front one, i.e. the surface facing the interfering beams is provided with a cut-out for the passage of radiation. The undevelopable hyperboloid is particularly useful when it is possible to apply the test layer in a liquid state on the surface of a body of said shape. After the layer has dried, the sensitive layer body is stored in an exposure device and the interference patterns are recorded. BACKGROUND OF THE INVENTION The hyperbole lies on lines passing through the intersection of light rays, impinging on the light-sensitive layer of individual light waves. 4. Method according to points. 1 and 2, characterized in that the photosensitive layer forms a tangent plane to the rotational hyperboloid. 5. A method according to claim 1, wherein the photosensitive layer is deposited on the surface of a circular cylindrical surface approximating the surface of the hyperbolic cylinder. 6. The method of claims 1 and 3, wherein the photosensitive layer forms a tangent plane to the hyperbolic cylinder.