| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain an alignment, completed before vacuum drawing, even after it by dynamically separating an optical system placed directly on an optical datum plane by an optical bench support and a vacuum container held on the optical datum plane by a vacuum container column support from each other. SOLUTION: An optical support base 4 is mounted directly on an optical datum base 3 with an optical datum plane by an optical support base column 5. A vacuum container 1 is supported by a vacuum container column support 2, a rigidity. Bellows 6 have the function of isolating the dynamic distortion between the structures of the vacuum container 1 and the optical support base 4, which are dynamically independent of each other. Even if the vacuum container 1 is thin and easy to be deformed during vacuum drawing, the optical support base 4 and an optical system housed inside the vacuum container 1 and supported by the optical support base 1 is free from the distortion and minute variation involved in the deformation of the vacuum container 1. Since the optical system housed inside the vacuum container 1 can hardly be deformed both before and after the evacuation of the air, therefore, the alignment of the optical system completed before it can be maintained.</p> |
