| 摘要 |
PURPOSE:To perform pattern comparison with high accuracy by generating a second pattern based on addition mean by selecting a first pattern fetched sequentially, comparing the second pattern with the first pattern fetched newly, and detecting pattern difference between them. CONSTITUTION:A laser beam with which the surface of a material 12 to be inspected is irradiated from a laser source 11 is scattered in two dimensional fashion, and is fetched in an input device 20, and also, is projected on liquid crystal displays 16a, 16b. The pattern of scattered light fetched in the input device 20 is converted to a pattern signal, and is supplied to an addition mean calculator 21 at an appropriate timing, and a mean pattern signal in which averaging processing is performed on gradation is supplied to a liquid crystal driving device 23 directly or via an inverter 22. A reference pattern that is the second pattern is generated by performing the addition mean of a fetched first pattern, and the pattern difference between the reference pattern and the first pattern is detected. In such a way, the second pattern is changed at high speed following the fluctuation of the first pattern, thereby, the pattern comparison with high accuracy can be performed. |
