| 摘要 |
PURPOSE:To enable the accuracy in the alignment of an optical system to be secured by supporting the resting table of the optical system by a part whose displacement is small within a specified range even when a vacuum container is deformed due to the change in atmospheric pressure. CONSTITUTION:A metallic target 1, a capacitor lens 2, an objective lens 3 and a reflection mirror 4 are provided on stages 7 through 10 over a plate 6 respectively in an vacuum container 5. And a soft X-ray detector 11 and a reflection mirror 12 are also provided on stages 15 and 16 over a plate 14 in a vacuum container 13. Each plate 6 and 14 is supported at three points, that is, at end sections 5a through 5c, and 13a through 13c of the bottom plates of the vacuum containers 5 and 13 respectively. And the movement of the stages 7 through 10, 15 and 16 is driven through universal joints. By this constitution, when the vacuum is drawn, each plate 6 and 14 is supported by means of three point suspension in opposition to the deformation of the vacuum containers 5 and 13, and even when each stage is driven, no transmission of unnecessary force is made because of the aforesaid constitution, optical alignment therefore will never be out of order. |
