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This paper describes a numerical development of image converters and intensifiers which incorporate an inverting electron optical system (EOS) and a microchannel plate (MCP) as an amplifier. The numerical design of the system includes calculation of the electrostatic field in the device, trajectories of electrons emitted from a photocathode, and determination of the modulation-transfer-function (MTF) which gives the objective estimation for the image quality.Results of the numerical experiments are shown, and the EOS with optimized characteristics is developed. It provides the nearly flat image surface, determines the position of the surface of the best focus, minimizes the image distortion and reduces a noise factor of the MCP.

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Abstract-Image converters and intensifiers give access to a larger spectral domain of electromagnetic radiation than the human eye. They amplify low light images and increase the eye sensitivity. The visual acuity, and therefore, the range of vision of any image detector, is limited by optical properties of the detector, such as a modulation-transfer-function (MTF) and the value of noise, produced by the device. This paper presents the methods and computational algorithms for calculating MTF and the noise factor of image converters and intensifiers which incorporate an inverting electron optical system and a microchannel plate as an amplifier. The approach, presented here, enables one to improve the visual acuity of the device.

Electron-optical devices with microchannel amplification have many advantages, except poor noise characteristics. In order to increase gain and reduce a noise factor a layer with increased secondary emission is deposited on the top of a contact conducting layer at the entrance of channels. Effects, arising in the channel amplifier with the high-efficiency emitter, are investigated in this work using the computational method, developed by the author. A computational method for simulation of stochastic processes of an electron multiplication is based on 3D Monte Carlo simulations and the theorems of serial and parallel amplification stages proposed by the author. The method provides a high calculation accuracy with minimal cost of computations. The computational model is used to investigate the effect on the noise factor of the incidence angle of the input electron beam, nonuniformity of the emitter surface, the depth and secondary emission yield of the high-efficiency emitter.Keywords Microchannel electron amplifier · Monte Carlo simulations · Nonuniformity of an emitter surface · High-efficiency emitter · Noise factor