SU573088A1

SU573088A1 - Photoelectronic instrument

Info

Publication number: SU573088A1
Application number: SU752178193A
Authority: SU
Inventors: А.Г. Берковский; А.Б. Костин
Original assignee: Предприятие П/Я А-3904
Priority date: 1975-10-03
Filing date: 1975-10-03
Publication date: 1981-03-30

Description

Изобретение относится к области ¹электронной техники, в частности к фотоэлектронным приборам с логарифмической амплитудной характеристикой, предназначенным для использования как в составе широкодиапазонных детекторов ионизирующих излучений, так и непосредственно для регистрации световых потоков, амплитуда которых меняется в широком диапазоне.The invention relates to field ^{1 of} electronic equipment, in particular to photoelectronic devices with a logarithmic amplitude characteristic, intended for use both as a part of wide-range detectors of ionizing radiation, and directly for recording light fluxes, the amplitude of which varies over a wide range.

Известен фотоэлемент с логарифмической амплитудной характеристикой, в котором для получения логарифмической характеристики перед входным окном помещены нейтральные светофильтры с различными коэффициентами пропускания [11 .A known photocell with a logarithmic amplitude characteristic, in which, to obtain a logarithmic characteristic, neutral filters with different transmittance are placed in front of the input window [11.

Недостатком такого фотоэлемента являются малая величина выходного тока и поглощение светофильтрами боль-20 шой части светового потока.The disadvantage of this photocell is the small value of the output current and the absorption by filters of most of the luminous flux.

Известен фотоэлектронный прибор, с логарифмической амплитудной характеристикой, содержащий анод, входное окно, рифленый электрод с впадинами 25 параболической формы, на поверхность которого нанесен фотоэмиссионный слой, а во впадинах помещены плоские э?-раны, перпендикулярные плоскости элек.тродз [21 . 30A known photoelectronic device with a logarithmic amplitude characteristic, containing an anode, an input window, a corrugated electrode with depressions 25 of a parabolic shape, on the surface of which a photoemissive layer is deposited, and flat e? -Ranes perpendicular to the plane of electrodes [21. thirty

Однако такой прибор имеет малый логарифмически й диапазон а м п л и т у д ь: о й характеристики - не более 13^. Прибор при чувствительности катода 30 мкА/лм работает в диапазоне интен сивностей светового излучения (10°10®) лм.However, such a device has a small logarithmic range of amplitude: its characteristics are no more than 13 ^. With a cathode sensitivity of 30 μA / lm, the device operates in the range of light emission intensities (10 ° 10®) lm.

Для расширения динамического диапазона в сторону'малых световых по’0 токов б предлагаемом фотоэлектронном приборе в плоскостях экранов, между ними и входным окном расположены пластины, причем на обе стороны этих пластин нанесен фотоэмиссионный 1 5 слой.To expand the dynamic range in the direction of "small light fluxes" 0 of the proposed photoelectronic device in the planes of the screens, plates are located between them and the input window, with a photoemissive 1-5 layer applied to both sides of these plates.

На чертеже схематично изображена часть конструкции фотоэлектронного прибора, представляющая собой отдельную ячейку, заключенную между двумя соседними экранами.The drawing schematically shows a part of the construction of the photoelectronic device, which is a separate cell, enclosed between two adjacent screens.

Указанная часть конструкции состоит из электрода 1 (рифленого электрода) со впадинами, с нанесенным на подложку эмиссионным слоем, пластин анода 2, пластин экранов 3 и входного окна 4. Электроны с фотокатода 5 бомбардируют эмиссионный слой на рифленом электроде 1 и выбирают электроны, которые оседают на аноде 2. Благодаря неоднородному ускоряю-Μζ / 77 30 88 * . »ι * .* щему градиенту у эмиссионной ‘поверхности фотокатода и рифленого электрода ограничение тока собственным пространственным зарядом происходит при различньтх плотностях эмиссионных токов. За счет введения каскада_#умножения динамический диапазон предлагаемого фотоэлектронного прибора увеличивается по сравнению с прототипом в сторону малых световых потоков примерно в число раз, равное коэффициенту вторичной эмиссии эмиссионного слоя на рифленом электроде.The indicated part of the construction consists of an electrode 1 (corrugated electrode) with depressions, with an emission layer deposited on the substrate, anode plates 2, screen plates 3 and an input window 4. Electrons from the photocathode 5 bombard the emission layer on the corrugated electrode 1 and electrons are deposited on the anode 2. Due to the inhomogeneous accelerating, Μζ / 77 30 88 *. To the gradient at the emission surface of the photocathode and corrugated electrode, current limitation by its own spatial charge occurs at different densities of emission currents. Due to the introduction of the multiplication cascade _# , the dynamic range of the proposed photoelectronic device is increased compared to the prototype in the direction of small light fluxes by approximately a factor equal to the secondary emission coefficient of the emission layer on the corrugated electrode.

Прибор при чувствительности катода приблизительно 30 мкА/лм и коэффициенте вторичной эмиссии эмиссионного слоя на_ш рифленом электроде приблизительно 10 работает в диапазоне интенсивностей светового излучения (10⁵-10^е) лм. Максимальный выходной ток более 10 А.Device sensitivity at the cathode of about 30 uA / lm and the emission coefficient of secondary emission layer on _w corrugated electrode 10 runs approximately in the range of light radiation intensities (10 ⁵ -10 ^e) lm. The maximum output current is more than 10 A.

Claims

The invention relates to the field of electronics, in particular to photoelectric instruments with a logarithmic amplitude characteristic, intended for use both as part of wide-range ionizing radiation detectors, and directly for recording light fluxes, whose amplitude varies over a wide range. A photocell with a logarithmic amplitude characteristic is known, in which to obtain a logarithmic characteristic, neutral filters with different transmittances l are placed in front of the input window. The disadvantage of such a photocell is the small size of the output current and the absorption by the light filters of the greater part of the light flux. A photoelectronic device with a logarithmic amplitude characteristic is known, which contains an anode, an input window, a corrugated electrode with troughs of a parabolic shape, on the surface of which a photoelectric layer is applied. Flat etrines are placed in the cavities, perpendicular to the plane of the electrodes 23. However, such a device has a small logarithmic range of amplitude response - no more than 10, The device with a cathode sensitivity of 30 μA / lm works in the d; -1 range of light intensities; Zluche and-: () lm. In order to broaden the dynamic range in the side light fluxes B, the proposed photoelectric device in the screen planes, plates are placed at the entrance window, and a photoemission layer is deposited on both sides of these plates. The drawing shows schematically a part of the design of a photoelectronic device, which is a separate cell enclosed by the two adjacent screens. This part of the structure consists of an electrode 1 (corrugated electrode) with hollows with an emission layer deposited on the basement, anode plates 2, screen plates 3 and an input window 4. Electrons from the photocathode 5 bombard the emission layer on the corrugated electrode 1 and electrons are chosen which are deposited on the anode 2. Due to the inhomogeneous accelerating gradient at the emission surface of the photocathode and the corrugated electrode, current limiting by its own space charge occurs at different densities of emission currents. Due to the introduction of a cascade of multiplication, the dynamic range of the proposed photoelectronic device increases compared to the prototype in the direction of small light fluxes by about a factor equal to the coefficient of secondary emission of the emission layer on the corrugated electrode. The device with a cathode sensitivity of approximately 30 µA / lm and a secondary emission coefficient of the emission layer on a corrugated electrode of approximately 10 operates in the range of light emission intensities () lm. Maximum output current is more than 10 A. Formula of the invention A photoelectronic device with a logarithmic amplitude characteristic containing an anode, an input window, an electrode with troughs of a parabolic shape, on the surface of which a photoemission layer is deposited, and flat screens perpendicular to the common electrode plane are placed on the cavities characterized in that, in order to expand the dynamic range in the direction of small sretovyh flows, plates are located in the planes of the screens between them and the entrance window, and on the side of these Lastin applied photoemissive layer. Sources of information taken into account when ek (lerting 1. US patent No. 2193687, CL H 01 J 39/16, published 1965.

2. USSR author's certificate 433899, cl. H 01 J, 1974.

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