| 摘要 |
PURPOSE:To prevent adhesion of foregin matter, and also to easily remove foreign matter which has adhered, by vapor-depositing a conductive film on at least one of the main surfaces of a quartz double refraction plate to whch mirror polishing has been performed. CONSTITUTION:A conductive film 3 such as In2O3, etc. is vapor-deposited on main surfaces 2, 2' of a quartz double refraction plate 1 to which mirror polishing has been performed. In this way, foreign matter becomes hard to adhere, and foreign matter which has adhered is also removed easily with a blower, etc. |
