SU410484A1 - - Google Patents

Description

one

The invention relates to electrovacuum technology, in particular, to methods for controlling the quality of electrovacuum devices.

There is a method of controlling an electron-optical converter by uniform illumination of the photocathode and recording the unevenness of the output signal. However, this method of control of the image intensifier does not provide information about defects in the form of dark and bright spots associated with the presence of technological contaminants on the photocathode, screen or in the amplifying tract, which are normalized depending on their location and size. Therefore, at present, the purity of the field of image intensifiers is assessed visually. Using a microscope, measure the size and calculate the area and the number of visible points on the screen.

In order to increase the accuracy of monitoring the purity of the field of view, a light beam illuminating the photocathode is proposed to be divided into two parts and the surface of the photocathode to be scanned with one part of the light beam. The light signal received on the screen of an image converter is converted into an electrical one and compared by amplitude and duration with another part of the light beam converted into an electrical signal and by the difference of these signals the purity of the field of view of the converter is evaluated.

The light beam, for example, from the screen of the electron beam tube, is separated by a beam-splitting mirror and one of the light beam is scanned by the working field of the photocathode.

Eopa. The luminous flux obtained on the screen of the converter, modulated by defects on the screen, photocathode and amplifying path of the image tube, is converted, for example, by a photoconverter into an electric one and sent to the input of the comparison unit. Another part of the light beam from the CRT screen after the dividing mirror is directed to the level setting unit, then also converted to an electrical signal and fed to the input of the reference signal of the comparison unit. By comparing the amplitudes and durations of the monitored and reference signals, the image intensifier is rejected by the contrast of points and spots on the working field of the photocathode. In the computing device, the size of the area is determined in accordance with the duration of the rejection signal and the resulting resultant signal on the location of defects in the visual field is directed to the indicator CRT and the actuator of the image intensifier.

25

Subject invention

The method of control of electron-optical

converter (EOC) by lighting

30 photocathodes with a light beam and detecting 3 unevenness of the output signal, differing from the fact that, in order to increase the accuracy of monitoring the purity of the field of view, the light beam is divided into two parts and the surface of the photocathode is scanned with one part of the light beam The EOC light signal is converted into an electrical signal and compared in amplitude and duration with the other part of the light beam converted into an electrical signal and the difference in these signals is estimated by the field of view of the converter.