SU959015A1 - Image converter - Google Patents

Description

The invention relates to optoelectronics and can be used in optical coherent information processing systems, for transforming and amplifying images, for projecting television images onto a large screen.

A device for image conversion is known, which contains a multilayer metal-photoconductive-liquid crystal (LC) structure — a metal, a power source, and an optical readout system. When an image is projected onto a semiconductor layer, the voltage is redistributed between the semiconductor layer and the liquid crystal layer. In the layer (LC), a potential relief is formed, corresponding to the distribution of light in the input image. Under the action of voltage, the LC changes its optical properties and modulates the readout radiation that forms the output image 1.

Such a device has low photosensitivity, low contrast of the transformed image and does not have long-term memory.

The closest to the present invention is an image converter, a multi-layered structure.

consisting of a successively located transparent electrode, a dielectric layer, a semiconductor layer, a dielectric layer, an electro-optical material layer, a transparent electrode, and a supply voltage generator connected to the electrodes and the source of read light. Optical recording is performed from the semiconductor side, optical reading from the liquid crystal sides.

. Under the action of the applied voltage, a high-resistance region is formed in the semiconductor layer. In the absence of light, the entire applied voltage falls on the layer of a perlucodusor. When the semiconductor is illuminated, voltage is transferred to

20 layer LCD. Under the action of the applied voltage, the LCD changes its optical properties and modulates the readout radiation forming the output image 2.

25

Such a device has low photosensitivity, low contrast of the transformed image and does not have long-term memory.

The purpose of the present invention

Claims (2)

30 is an increase in the sensitivity of the device and the contrast of the transformed image, as well as the creation of a long-term memory. . This is achieved due to the fact that the image converter contains a multilayer structure consisting of successively located transparent electrode of the dielectric layer, semiconductor layer, dielectric layer, layer of electro-optical material, transparent electrode, as well as alternating voltage generator connected with electrodes, and a source of reading light, the dielectric layer between the electrode and the semiconductor layer is made of a light-emitting material. The drawing shows the structures to the image converter circuit and its power up circuit. The device consists of a successively arranged electrode 1, a light-emitting layer 2, a semiconductor layer 3, a dielectric field 4, a layer of electro-optical material 5, a transparent electrode b, and an alternating voltage generator 7 and a reading light source 8. An image is projected onto the structure polarized effects, polarizers 10 are inserted into the readout path. The operation of the device is as follows. When a voltage pulse is applied to the electrodes 1 and 6, a depleted high-resistance layer is formed in the semiconductor and all the voltage applied to the structure drops on the semiconductor. When a semiconductor is illuminated (image projection 9), its resistance drops and the voltage is transferred from the semiconductor layer to the light-emitting layer and the layer of electro-optical material. In these layers, potential reliefs are formed, corresponding to the intensity distribution in the input image. The layer of electro-optic material under stress changes its optical properties and opens the readout path. At the same time, under the action of voltage, photons are generated in the light emitting layer. This leads to an increase in the photoconductivity of the semiconductor. A reverse positive connection occurs between the semiconductor layer and the light emitting layer. An increase in the photoconductivity of the semiconductor leads to an even greater increase in voltage on the layer of electro-optical material and an even greater opening of the optical readout path. This is not observed in the darkened areas of the device, so such a positive feedback allows the contrast of the image generated by the device to be increased. The presence of feedback leads to an ohm that is sufficiently weak in intensity from an external light pulse, so that the radiation of the light-emitting radiation brought the system to a state with maximum modulation by a layer of electro-optical material of the reading radiation. Those. such a system has long-term memory, and is in the on state until the voltage is applied to it. At the same time, the external light pulse power is significantly less in this device than in the known for the same modulation of the read beam in both devices, therefore, photosensitive. This device is higher. An experimental test was carried out on high-resistance silicon structures ILC-654, using a phosphor as a light-emitting layer. As a result of the experiments, an increase in photosensitivity by a factor of 2 was detected, and the image contrast was increased by a factor of 1–3. The device provides a memory of the transformed image during the operation of the supply voltage. Thus, this device allows you to convert weak optical signals, while providing higher photosensitivity and contrast of the image generated by the device, as well as long-term memory. An image converter comprising a multilayer structure consisting of consecutively arranged transparent electrode, dielectric layer, semiconductor layer, dielectric layer, layer of electro-optical material, transparent electrode, as well as a voltage supply generator, coe fi ned with electrodes, and a source of read light, characterized in that, in order to increase the sensitivity of the device and the contrast of the transformed image, as well as create a long-term memory, dielectric nonstoichiometric layer between the electrode and the semiconductor layer is made of a light-emitting material. Sources of information taken into account in the examination 1. US patent number 4018509, cl. 350-160, 1977. 2.Snharulidze D.G. and others. Liquid-crystal converter of non-coherent image into coherent one based on semiconductor-dielectric type structure. - Quantum Electronics., 1979, tb, pp. 1271-1277. f 2 -s