Granularity of Dental X-ray Film

Fundamental Investigation of Wiener Spectrum Measurement

Abstract

We developed a 16 k dots × 100 lines Wiener spectrum measurement system using a microscope-television camera system. Heretofore, the granularity of film was evaluated from Wiener spectrum using Wiener spectral value in the spatial-frequency independent region, but this factor is determined by the measurement system and the film emulsion density and there were problems in the evaluation of granularity. We established a new method for evaluating the granularity from Wiener spectral values in the spatial-frequency independent region through Wiener spectrum measurement system that utilized a microscope-television camera system as the input device.