SU890486A1 - Photoresistor - Google Patents

Description

(54) PHOTORESISTOR

one

The invention relates to electronic engineering and can be used to make photoresistors.

A photoresistor is known, which contains an isolating substrate, on which a photoconductive layer and electrodes 1 are located.

The disadvantage of this photoresistor is low radiation resistance.

The closest technical solution to the invention is a photoresistor containing a photosensitive element in the form of an insulating substrate, on which a photoconductive layer and two collecting electrodes are placed, and a control electrode, located in housing 2.

A disadvantage of a known photoresistor is low radiation resistance .15

The purpose of the invention is to increase the radiation resistance.

The goal is achieved by the fact that in a photoresistor containing a photosensitive element in the form of an insulating substrate on which the photoconductive is placed. the layer and 20 two collecting electrodes, and the control electrode located in the housing, the control electrode is made in the form of a dielectric plate located opposite the insulating substrate, with a layer of tin oxide deposited on it from the side of the photoconductive layer and two additional collecting electrodes that are placed symmetrically to the collecting electrodes of the photosensitive element and electrically connected to them.

The drawing shows schematically a photoresistor, a general view, a slit.

Claims (2)

The photoresistor contains a photosensitive element fixed in the housing 1, made in the form of an insulating substrate 2 made of quartz, sapphire or glass, on which is placed a photoconductive layer 3 made of lead sulfide and two low-resistance collecting electrodes 4, and a control electrode made in the form of a dielectric plate 5 from quartz, sapphire or glass located opposite the insulating substrate 2, with a layer of tin oxide 6 deposited on it from the side of the photoconductive layer 3 and two additional collecting electrodes 7, which are placed with immetrically collecting electrodes 4 of the photosensitive element and electrically connected with them by leads 8. Case 1 is equipped with insulators 9, inside which current leads 10 are located. In case I, a window 11 is made to transmit the radiation flux. The operation of the photoresistor is carried out as follows. The flow of the detected radiation, indicated by an arrow in the drawing, passes into the window 11 in the housing 1, enters through the dielectric plate 5 and the tin oxide layer 6 (transparent in the IR region of the spectrum of the photosensitive element), and after connecting the current leads 10 to the electrical circuit through the photoconductive a layer 3 and a layer of tin oxide b flow an electric current creating a potential gradient on each of layers 3 and 6. Since each of the pairs of collecting electrodes 4 and 7 electrically interconnected is under one their potential, and the distances between the collecting electrodes 4 of the photosensitive element and the collecting electrodes 7 of the control electrode are equal, the potential gradient on the photoconductive layer 3 and the tin oxide layer 6 are the same; As a result, the electric field in the gap between the photoconductive layer 3 and the tin oxide layer b is compensated and equal to zero; therefore, the gas molecules ionized by radiation in this gap are no longer separated, and they only recombine mainly into diffusion processes and the surface of the photoconductive layer 3 is not affected, and the photoresistor operates in the field of ionizing radiation without significant changes in the photoelectric parameters. The simplicity of the photoresistor device and its high radiation resistance expand the field of application of photoresistors in devices exposed to ionizing radiation. The invention includes a photoresistor containing a photosensitive element in the form of an insulating substrate, on which a photoconductive layer and two collecting electrodes are placed, and a control electrode located in a housing, characterized in that, in order to increase radiation resistance, the control electrode is made in the form of a dielectric a plate located opposite the insulating substrate, with a layer of tin oxide deposited on it from the side of the photoconductive layer and two additional collecting electrodes that are placed en- collecting electrodes of the photosensitive member and electrically connected with them. Sources of information taken into account during the examination 1. USSR author's certificate No. 451130, cl. H 01 L 31/08, 1972. 2.Patent Poland number 77502, cl. H 01 L 31/08, 1973 (prototype).