| 摘要 |
PURPOSE:To make it possible to perform highly accurate measurement, by refracting a light path from a sample surface through a lens system by mirrors, forming the images on individual light receiving parts, and selectively setting the position of the sample surface by the movements of the mirrors. CONSTITUTION:A light path 3 from a sample surface 1, which is formed by a lens system 2, is divided into a first light path 5 and a second light path 6. At the intermediate parts of the first light path 5, a first mirror 7 and a second mirror 8 are positioned, and an image is formed on a first light receiving part 9. At the intermediate part of the second light path, a third mirror 10, a fourth mirror 11, and a fifth mirror 12 are positioned, and the second light path is refracted. The image is formed on a second light receiving part 13. With the first mirror 7 and the mirror 8 being arranged in parallel, one or both mirrors are moved along the second light path 6. By selectively setting the position of the sample surface, highly accurate measurement can be performed. |
