The article deals with the problem of using the method of optical spatial filtration, applied at present in radiodiagnosis for solving a number of problems connected with image processing in order to reduce the influence of disturbances, to compensate the transfer functions, etc. The process of the formation of roentgen shadow projection is described by integral equations. In this way the possibility for correcting a posteriori the transfer characteristics of the processes of the formation and fixation of roentgenograms has been revealed, and the maximum dimensions of objects capable of being successfully processed by spatial filtration, as well as the necessary filtering functions of the correction filter, have been determined. The problem of measuring the transfer characteristics of radiodiagnostic systems is discussed, and the method of measuring the complex transfer function, suitable for the spatial variant system, is proposed. On the basis of a short review of publications on this problem, and taking into consideration the above analysis, the trends of using the methods of optical filtration are determined. The authors believe that these methods used within the determined trends may improve the quality of roentgen images and, in the end, the diagnostic value of roentgenograms.
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Sensors (Basel)
January 2025
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