| 摘要 |
PURPOSE:To adjust the back focus of an image-pickup element by image-picking up a picture in the prescribed relation to the pixel pitch of an solid-state image- pickup element by the repeating pitch, and detecting the beat component based upon the difference between the repeating pitch and the pixel pitch. CONSTITUTION:The image-pickup light of the test pattern by a test chart 10 for measuring the registration is irradiated through a color separating prism 30 to CCD image sensors 31r, 31g and 31b. For the image-pickup output by the sensors 31r, 31g and 31b, the central pattern only of the test pattern is taken out through gate circuits 42r, 42g and 42b. The amplitude of the beat component included in the picture output of the central part is changed depending upon a image-pickup optical type back focus. Then, while the beat component is observed in waveform by the oscilloscope 44, position adjusting jigs 40r, 40g and 40b are operated. Then, the position of the sensors 31r, 31g and 31b can be adjusted to the position of the just focus. |
