SU675624A1

SU675624A1 - Image brightness control

Info

Publication number: SU675624A1
Application number: SU2566830A
Authority: SU
Inventors: Владимир Иванович Коротеев; Александр Васильевич Михалев
Original assignee: Сибирский Институт Земного Магнетизма; Сибирский институт земного магнетизма, ионосферы и распространения радиоволн СО АН СССР; Ионосферы И Распространения Радиоволн Со Ан Ссср
Priority date: 1978-01-05
Filing date: 1978-01-05
Publication date: 1979-07-25

Description

(54) УСТРОЙСТВО ДЛЯ РЕГУЛИРОВАНИЯ ЯРКОСТИ ИЗОБРАЖЕНИЯ(54) DEVICE TO ADJUST BRIGHTNESS IMAGE

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Изобретение относитс к радиотехнике и может использоватьс дл регулировани изображени на выходе электронно-оптического преобразовател (ЭОП), примен емого при наблюдении объектов переменной ркости.The invention relates to radio engineering and can be used to adjust the image at the output of an electron-optical converter (EOT) used in the observation of objects of variable brightness.

Известно устройство дл регулировани ркости изображени , содер ащее интегратор , выход которого подключен к первому входу блока сравнени , к второму входу которого подключен выход источника опорного сигнала, при этом выход блока сравнени подсоединен к электронно-оптическому преобразователю через коммутатор, к второму и третьему входам которого подключены соответственно выход блока временной выдержки и источник питани 1.A device for adjusting the image luminance, containing an integrator, the output of which is connected to the first input of the comparison unit, to the second input of which the output of the reference signal source is connected, and the output of the comparison unit connected to the electron-optical converter through the switch, is known to the second and third inputs of which the output of the time-delay unit and the power source 1 are connected respectively.

Цель изобретени - повышение точности регулировани .The purpose of the invention is to improve the accuracy of regulation.

Дл этого в устройство дл регулировани ркости изображени , содержащее интегратор , выход которого подключен к первому входу блока сравнени , ко второму входу которого подключен выход источника.For this purpose, an image brightness control device containing an integrator, the output of which is connected to the first input of the comparator unit, to the second input of which the source output is connected.

2опорного сигнала, при этом выход блока сравнени подсоединен к электронно-оптическому преобразователю через коммутатор , ко второму и третьему входам которого подключены соответственно выход блока временной выдержки и источник питани , второй выход блока сравнени подключен к управл ющему входу интегратора.The reference signal, while the output of the comparator unit is connected to the electro-optical converter through a switch, to the second and third inputs of which the output of the temporary holding unit and the power source are connected, the second output of the comparator unit is connected to the integrator control input.

На чертеже приведена структурна электрическа схема предложенного устройства.The drawing shows a structural electrical circuit of the proposed device.

Устройство дл регулировани ркости изображени содержит интегратор 1, блок 2 сравнени , источник 3 опорного сигнала, блок 4 временной выдержки, коммутатор 5, источник 6 питани и электронно-оптический преобразователь (ЭОП)7.The device for adjusting the brightness of the image contains an integrator 1, a comparison unit 2, a reference signal source 3, a time-delay block 4, a switch 5, a power supply 6 and an electron-optical converter (EOC) 7.

Устройство работает следующим образом.The device works as follows.

Сигналом с блока 4 запускаетс коммутатор 5, который подключает источник 6 питани к электронно-оптическому преобразователю 7.The signal from block 4 starts the switch 5, which connects the power source 6 to the electron-optical converter 7.

Claims

The signal from integrator 1 corresponding to the total luminous flux emitted from the screen of the electro-optical converter 7 during the integration time is compared with the signal of the source 3 of the reference signal in comparison unit 2, which switches off switch 5 and resets previously accumulated on integrator 1 signal. The next pulse from block 4 starts switch 5 and the whole cycle repeats. The sum of the luminous flux emitted by the screen of the electron-optical converter 7 during the time between the pulses of the comparison unit 2 is proportional to the magnitude of the signal of the source 3 reference signal, and this is achieved by adjusting the brightness of the image at the output of the electron-optical converter 7 within the specified interval and for a long time intervals of time. The afterglow of the phosphor of the screen at the end of one working cycle is recorded in the next cycle, as a result of which a full light sum is emitted, which is emitted by the screen of the electron-optical converter 7 over the entire observation period, and this is what turns the image brightness control accuracy. The absolute error in controlling the total light sum emitted by the screen of the electron-optical converter 7 for any period of time in the proposed device does not exceed the value of the light sum recorded in one working cycle and does not depend on the duration of the observation, while the absolute error in controlling the light sums in the device the prototype is equal to the sum of the luminous fluxes of the afterglow of the phosphor of the screen of each working cycle for the entire observation period, and in the general case varies in proportion to the duration this gap. This means that the error in adjusting the image brightness, equal to the absolute control of the total light sum emitted during the observation period divided by the value of this period, tends to zero in the proposed device, while the prototype device regulates the average image brightness with a known error. Thus, the accuracy of adjusting the brightness of the image in the proposed device in comparison with the prototype increases in an incommensurate number of times. In addition, an increase in the frequency of adjustment cycles (pulse frequency of the time-exposure block) leads to an increase in the error in adjusting the image brightness in the prototype due to an increase in the number of overshadows in any given time interval, while in the proposed device the error in adjusting the image brightness remains unchanged. . . Thus, the proposed device allows almost completely to get rid of the error of adjusting the image brightness and to maintain the achieved accuracy when changing the operating modes of the converter. For example, during a thousand cycles of adjusting the brightness of the image in the proposed device, the regulation error will not exceed 1/1000 of the recorded light sum, while in the prototype this Organizer depends entirely on the amount of overexposure in each adjustment cycle and can reach from 1/5 to 1 The magnitude of the detected light sum, which is more than 100 times greater than the error in adjusting the brightness of the image in the proposed device. Claims An image brightness control device comprising an integrator, the output of which is connected to the first input of the comparison unit, the second input of which is connected to the output of the reference signal source, while the output of the comparison unit is connected to the electron-optical converter through a switch, to the second and third the inputs of which are connected, respectively, to the output of the time-delay block and the source of the gshtan, characterized by those that, in order to increase the control accuracy, the second output of the comparator unit is connected to the integrator control input. Sources of information taken into account during the examination 1. Author's testimony of the USSR No. 554642, cl. H 04 N 5/58, 1977.