| 摘要 |
PURPOSE:To obtain the specified detection accuracy regardless of varied light quantity without accompaniment of binary level, by projecting a light ray onto a specimen uniformly in the longitudinal direction, however, in the traversal direction in such a way that the light quantity decreases progressively from one end to the other and by picking up its regular reflected image. CONSTITUTION:A light ray from a line light-source 1 is projected slantedly from above on to a specimen 2 and its regular reflected image is picked up by a TV- camera 3 laid out in the opposite position of the light source 1. After amplifying an image signal from the TV-camera 3 by an amplifying circuit 4, A/D conversion is made by an A/D convertor 5 and the converted data is written in a memory 6. In this case, a light quantity measuring circuit 7 measures light quantity of the regular reflected image from an output of the amplifying circuit 4, controls offset and gain of the amplifying circuit 4 automatically and the A/D conversion is executed between maximum and minimum values of portions of signals of the specimen and further, performs software processing of image data of the specimen 2 written in the frame-memory by a computer 8. |
