SU1187136A1 - Device for producing volume colour image - Google Patents

Description

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Stencil. Polarizer Paul ryzapch}. To u / cheprempl. Wednesday

Photoshop

Prism

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The invention relates to a technique of raster optics and is intended for capturing and reproducing color volumetric images of objects in incoherent light.

The purpose of the invention is to obtain a volumetric color image of an object.

FIG. 1 shows the proposed device j in FIG. 2 shows the operation of the device in the modes of capturing and reproducing the image J in FIG. 3 obtaining a discrete spectrum when light passes through a system of two polarizers and a birefringent medium; in fig. 4 - graphs of image contrast versus Kg and g.

The device consists of sequentially between stencils, a first polarizer, a birefringent medium and a second polarizer, and a prism is inserted between the second stencil and the photoplate. In the image capturing mode (Fig. 2), the luminous flux from the object 1, illuminated by the incoherent light source 2, is divided by a system of two stencils 3 and 7 into a finite set of rays, the spectrum of which as a result of passing through the first polarizer 4, birefringent medium 5 and the second polarizer 6 becomes discrete. The light rays that have passed through the second stencil pass through a prism 8, in the code of which each beam is split in space into a discrete set of spectral components, which are fixed on a photographic plate 9. The photographic plate is reversed and a positive image is obtained. As a result, the spectral components of different light rays from the object, which have passed through both stencils from different angles, are fixed in the form of a set of transparent points on the photographic plate.

In the image playback mode, the device is illuminated with an incoherent source 11 from the side of the photographic plate 9 with diffused light, for example through a matte glass tO, and a pseudoscopic image of the object is observed from the side of the first stencil 3.,

Obtaining a discrete spectrum of white light in the mode of image fixation and operation of the device in the mode

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Image playback is as follows.

A bunch of white light will pass some hole of the first stencil and. the first polarizer acquires a linear (e.g., vertical) polarization in all spectral components. The birefringent medium, which can be used as an Iceland spar plate, cellophane film, etc., is oriented in such a way that the luminous flux with linear polarization on it splits into two equal orthogonal polarized components, one of them, passing through this medium is delayed relative to another for some time interval t. Since, depending on the wavelength (D i), this time delay leads to different phase differences between the indicated orthogonal components for different spectral components of white light, then at the output of the birefringent medium the white light spectral components acquire different polarizations (FIG. Figure 2 shows the polarizations of the white light spectrum at the output of a birefringent medium.

in the case of about 6 A

where a p

f

 0.38 μm - the wavelength of the dark-violet line of the spectrum).

After the passage of white light with such a polarized structure ordered through the spectrum through the second polarizer, oriented so as to suppress horizontal polarization, at its output we obtain a vertically polarized light that has no spectral components that are absent or significantly weakened (Fig. .Zb) In this case, the larger, the more closely located to each other are the intensity maxima on the graph, and the number of these maxima is orI

Approximate equal to N -7u-g

so large that each spectral region (red, green, blue) has several maxima, then such light retains sufficiently complete information about the color of the original light beam, if it was not white, but colored. After passing the beam of light from the output of the second stencil through a prism, the spectral components

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spatially separated and fixed on the photographic plate as separate points corresponding to the maxima of the graph of Fig. 36. At the same time, by choosing the exposure time and the photo plate development mode, the required j values (Fig. 3b) and the corresponding diameters of the indicated points can be provided.

The playback mode is as follows.

A photographic plate with a multitude of transparent points corresponding to the fixed spectral components of the various light rays from the object is illuminated by diffused white light through a frosted glass 10 (Fig. 2). At the same time, there will always be such directions of light rays that have passed through the transparent points of the photographic plate, that they will fall on the prism at the same angles at which they left

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in the image recording mode, the corresponding spectral components, therefore, the same spectral components after passing through the prism (now in the opposite direction) will gather into rays of light and then pass through both stencils, creating for the observer before the first stencil, a pseudoscopic image of the object in as a set of bright points, the color of which corresponds to the spectral composition of the light rays recorded earlier on the photo cantilever.

Thus, the device allows recording and reproducing a color image of an object as a set of colored bright points distributed in space using a source of white incoherent light and a black and white photographic plate.

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Claims (1)

DEVICE FOR PRODUCING VOLUME COLOR IMAGE, containing two stencils made in the form of plates with a large number of holes, and a photographic plate for black-and-white printing, characterized in that, in order to obtain a color image, the first polarizer located in series between the stencils is inserted, a plate of birefringent material and a second polarizer, and a prism is introduced between the second screen and the photographic plate. <g 345 mreTT’Tis Stencil Polarizer \ Stencil Polarizer. Muluchereloplop. Wednesday Figure 1