SU725512A1 - Method for recording holograms - Google Patents

Abstract

THE METHOD OF HOLOGRAM REGISTRATION by means of integral illumination of an object, converting an integral image into a coherent one, and recording an interference pattern formed by subject and reference beams, characterized in that, in order to increase sensitivity and resolution, as well as register holograms in real time, the conversion of an integral image into a coherent one • is performed by modulating the image of an object registered on a photothermoplastic carrier jiHTeproduction thief reduction kogerentnm light registered pattern, and uses the first order of diffraction as the object beam during recording gologramm.i (/}

Description

t, 7 The invention relates to the field of optoelectronics, in particular, the registration of a go. tomogram of an object when it is illuminated with a non-coherent beam of light and can be used to record holograms of non-stationary objects, as well as in pattern recognition systems. There is a known method of registering an intensity hologram with its incoherent illumination, which is based on the hologram property to successively accumulate interference patterns from several objects in a series of consecutive exposures of each individual object. In order to get an interference pattern from each object (or each element of the object) 5, the light wave scattered by each element is triggered by means of a diffraction grating into two spatially coherent waves, which are m create a contrasting interference pattern. . . (... - -. The disadvantage of the described method is the need to illuminate the object with monochromatic light, as well as the reduction of contrast interference bands in the hologram as the configuration of the object becomes more complex. The closest technological solution is the method of recording holograms by illuminating the object with tegral light, converting the integral image into a coherent one and recording the interference pattern of the radiation formed by the object and reference beams. In this method, the image of the object illuminated by the integral The incoherent light projected onto the photo-conducting film of selenium in the presence of an electric field is accumulated as a potential relief that induces the Pokkals effect in an electro-crystal that is used as a modulating medium. dielectric mirroring that optically separates the write and read functions. The scaling is effected by laser light. A coherent light beam is directed at the crystal. The beam mirror-tuned from the crystal is modulated by polarization in accordance with the image projected onto the photo-semiconductor. The polarization beam splitter converts the modulation of a beam from polarization to modulation by intensity. This beam of light, together with the reference beam from the same, | The laser forms a hologram that is recorded on a photographic plate. ..... The disadvantage of this method is its low resolution (20 mm), relatively low uro). Sensitivity is also used to record the image and hologram of two different recording media. The aim of the invention is to increase the sensitivity and resolution, as well as real-time recording of holograms. The goal is achieved by converting the integral image into a coherent one by modulating the image of the object recorded on the photothermoplastic carrier by an interference pattern, restoring the recorded pattern to the light coherent light, and using the first diffraction order as the Object beam. P ROME An image of an object illuminated by daylight is projected onto the FTP using an optical system. At the same time, two beams from the LG-78 laser are projected on the photothermoplastic carrier (FTPN). These rays are formed by another optical system. In this way, an interferential raster is recorded on the FTPN along with the image of the object. The angle between the interfering beams is chosen so that the spatial frequency of the obtained raster corresponds to the resonant frequency of the thermoplastic layer (for example, for plastic with a thickness of 0.5 µm, this frequency is about 800 and the angle is). The temperature of the PFED and the potential of the corona are maintained optimal (for the plastic used, they constitute, respectively, 8 kV). The image and the interference raster are projected at the same time as the corona on the ftpn;

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based fotopoltupropodnika ASj S 3 and the thermoplastic copolymers of styrene with butilfetakrilatom based on a transparent electrode of chromium, in the process of forming da FTS j Update distribution image in transmitted light in the first diffraction peaks can observe the reconstructed beams create an interference raster image object to a coherent fO light One of the diffraction peaks is projected on the cell dp of the recording, in which the FTP is also located. At the same time, another nySoK 15 from the same laser, which serves as the same, is sent to this FTPN; reference when recording a hologram. Since it is proposed to use the same FTP for recording the image and the hologram, the recording conditions and angles between the beams are the same here. The finished hologram is obtained in about 1 second,

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Thus, the method, due to the high resolution of the applied FTPN (up to 2000 i, allows to register a hologram of an object).

It is illuminated with an integral light with a resolution limited by optics that can exceed 500 mm. The high sensitivity of the recording medium (more than 10), its wide spectral range makes it possible to use low-power and widely accessible helium-neon lasers for recording holograms. The proposed method allows the recording of holograms of non-stationary objects, such as a portrait of a person, to obtain their spatial filters, simplifying the requirements for non-coherent radiation used for recording.

This method makes it possible to unify the equipment used (l records, by using for recording images and a hologram of one type of recording medium (FTP),

At the same time, this makes it possible to obtain holograms of non-stationary objects both in real time and memorize the image, and then to record it at the Right time. hologram.

Claims (1)

HOLOGRAM RECORDING METHOD by illuminating an object with integral light, converting an integrated image to a coherent image and recording an interference pattern formed by subject and reference beams, characterized in that, in order to increase sensitivity and resolution, as well as recording holograms in real time, converting the integrated image coherently produced by modulating the image of an object recorded on a photothermoplastic carrier by interference races thief recovery coherent light zaregistriro- g bathroom pattern, and using the first diffraction order as the object beam from the recording of holograms. SU p „725512