SU1720058A1 - Method of manufacturing lens raster - Google Patents

Abstract

The invention allows to simplify the process. Additional lens elements are formed on the initial lens-raster surface by applying a liquid optically transparent curing composition. The refractive index of the composition ... in the hardened state is different from the refractive index of the original lens-lens surface. 2 hp ff.

Description

The invention relates to optical instrumentation and can be used, in particular, in the printing industry for the production of stereo images.

The purpose of the invention is the possibility of producing a set of lens rasters with a wide range of focal lengths.

The method is carried out as follows.

A liquid curing, optically transparent composition is applied to the lens-raster surface with a known refractive index, and then it is cured. Moreover, the refractive index of the applied composition in a hardened state is different from the refractive index of the lens-raster surface.

To increase the focal length, a liquid-curing, optically transparent composition with a refractive index less than the refractive index of the lens material is applied to the lens-raster surface, and to obtain a raster with a negative focal distance, the liquid cured optically transparent surface is applied to the lens-raster surface. composition with a refractive index greater than the refractive index of the lens-raster surface ...

To obtain a lenticular screen with a given focal distance, the refractive index of the applied, liquid, optically transparent curing composition is determined by a calculation method ..

It is known that the optical power of the contacting lenses is equal to the sum of the optical forces of the components

1-1 + 1 f f 1 f2

(one)

where f is the focal distance of a system of two lenses;

fi is the focal distance of the 1st lens: h is the focal distance of the 2nd lens. The focal length of a thin lens is determined by the formula

one

f -p

(N-1) (1 / Ri -1 / R2)

(2)

cl

with

VI th o ate

00

where N is the relative index of refraction, equal u / P2 (ni is the index of refraction of the lens, is the index of refraction of air);

Ri is the radius of curvature of the first lens surface;

R2 is the radius of the second surface.

In this case, the focal lengths of the adjoining individual lenses will be equal to:

(P 1 / P2 - 1) (1 / R1 -1 / R2)

(3)

f2

(P2 / P2 1) (1 / R3 1 / R4)

(four)

The manufacturing conditions of the lenticular screen are such that

Ri;

Rz Rz - R,

then the expressions for the focal lengths of the individual lenses take the form:

 one . / .i.-iv h / d)

s

Gsh / p2 -IH-1 / Yu

one

(6)

(PZ / G12 1) 1 / R Substitute (5) in (6) into equation (1) and solve the equation with respect to the refractive index of the applied composition (p1). The result is

R-IT2

u pzf

where p z is the coefficient of refraction of the material of the lens elements of the original raster;

P2 - the refractive index of air; -

R is the radius of curvature of the lens elements;

f is the specified focal distance of the raster being produced.

 PRI m e r 1. The original lens raster has the following characteristics: 0.3 mm pitch; focal length 0.6 mm; the refractive index of the material of the lens elements is 1.56.

A melt of polymethyl methacrylate with a refractive index of 1.49 is applied onto the existing lens-raster surface by the method of irrigation, and a glass plate treated with an anti-agent, dimethyldichlorosilane, is pressed on top. cooled, then the glass plate is separated from the resulting raster. By measuring on a microscope, the focal length of the resulting raster is determined, which is 7.1 mm.

Example 2. The original point lens raster. made on a layer of chromed gelatin, which was duplicated

under the influence of light through a mask and manifested by hot water, has the following characteristics: step 0.2 mm; focal distance 0.5 mm; the refractive index of the material of the lens elements is 1.48.

A layer of epoxy adhesive of the composition, parts by weight, is applied onto the initial lens-raster surface, parts:

Epoxy resin ED-20100

10 Hardener - diethylamine 10

The glue is applied in such a way that it completely covers the lens elements, the glass plate treated with the antiadhesive - dimethyl - 15 dichlorosilane is pressed on top. the adhesive is cured in a drying oven at 40 ° C for 1-1.5 hours and the glass plate is removed. The refractive index of the cured epoxy adhesive is 1.56. The focal 20 distance of the resulting raster is 2.5 mm.

Claims (3)

1. A method of manufacturing a lens raster, comprising forming on 25 lens-raster surface with a specified refractive index of additional lens elements, which is so that, in order to simplify the technological process, additional elements 30 is formed by applying a liquid optically transparent curable composition to the lens-raster surface, and then curing it, and the refractive index of the applied composition in a different state is different from the refractive index of the lens-raster surface. 2. The method according to claim 1. of tl and h and y. u and i. that. In order to increase the focal length, additional lens elements are formed by applying to the lens-raster surface a liquid optically transparent curing com- position, the refractive index 45 which in the cured state is less than the refractive index of the lens-raster surface. 3. The method according to claim 1, characterized in that, for the purpose of making rasters c, 50 negative focal length on the lens-raster surface is applied liquid optically transparent curing composition, the refractive index of which in the cured state 55 more than the refractive index of the lens-raster surface.