| 摘要 |
PURPOSE: To measure a transmission function related to the resolution of a video camera and to determine also a frequency response to a phase by photographing a sufficiently narrow bar pattern, selecting a narrow electric pulse and executing discrete Fourier transformation. CONSTITUTION: Even when a sufficiently thin bar pattern is photographed when the video camera has ideal transformation characteristics, i.e., when ideal transmission characteristics is obtained on an output terminal, an extremely narrow electric square wave corresponding to the pattern is outputted as a video signal. Thereby a sufficiently narrow bar pattern capable of neglecting the amplitude of an electric pulse obtained from a video camera 1 to be measured by the scanning of the bar pattern by the camera 1 and the influence of bar width to a phase response is photographed, a sufficiently narrow width electric pulse is selected as an electric pulse to be obtained on the output terminal of the camera 1 and the obtained electric pulse is processed by discrete Fourier transformation. Consequently a phase response and group delay characteristics are determined in addition to an amplitude response. |
