Persons

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The secondary-emission multiplier of spatial-distributed flows of electrons - microchannel membrane - determines along with the photocathode, luminescent screen, electron-optical system determines the amplifying characteristics of the electron-optical transformers, photoelectronic multipliers. This, in its turn, determines the application areas and the operating range of the items. The actual task is an improvement of the microchannel membrane parameters and the search for new approaches to manufacture on alternative materials of the secondary-emission multipliers. In the paper the use of self-organizing high-ordered porous anode structures of aluminum oxide as the secondary-electronic emitters have been considered. The theoretical and practical approaches to development and the implementation of the computer models of processes of multiplying electrons in the channel of the based on aluminum oxide, have been offered. Based on the results of the calculations, performed using this model, the amplifying ability of such channels has been determined, their optimal caliber is 25, and the supply voltage is 300 V. A comparative analysis of these characteristics of secondary electron multipliers with corresponding parameters of microchannel plates based on lead silicate glass has been performed. It has been determined that that porous anodized alumina may be suitable for the manufacture of secondary electron multipliers. Its secondary emission ability is comparable to lead silicate glass.

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An important unit of an electron microscope is the system controlling the electron beam, responsible for raster forming on the specimen and the electron probe focusing, which provides an achievement of minimum of aberrations and the maximum of resolving capacity of formed electron image. During using electron microscope the image quality gradually deteriorates, manifesting the resolving capacity reduction and the astigmatism appearance. An attachment developed for the raster electron microscope, permitting to perform the highly effective diagnostics of the configuration of the scanning electron beam, controlled by a precision magneto-optical system, has been offered. It has been shown that the direct visual observing the scanning electron probe, in particular the evaluation of the ellipticity of its cross-section using the WEB camera matrix, combined with the sample plane, as a result, provides more efficient tuning and repair of the scanning electron microscope.

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The problem of increasing the conversion coefficient of two-chamber electro-optical converters used in the night vision technique has been considered. The results of the study on the influence of the vacuum processing technology for both chambers of the given products on their amplifying ability have been given. The methods have been proposed for increasing the level of conversion by changing the temperature-time mode of processing the photocathode of the first chamber of the device, as well as optimizing the sputtering of chromium on the mica substrate of the cathode of the second chamber. During the research, instrumental, expert and statistical analysis the non-destructive and destructive technological control have been used. As a result, an increase of the yield of products in terms of the conversion rate has become 35 %, an increase of the average value of η has become 65 %.

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