| 摘要 |
PURPOSE:To contrive the improvement of machining accuracy and heat resistance by making a coated conductive film on the surface of a knife edge of one side extended externally from a supporter made of a metal plate and one of diamond, sapphire or ruby. CONSTITUTION:A supporter 10 made of a metal plate is a half of circular disk, a recession 11 is provided at the center and a knife edge from 20 made of 100mum thick diamond is attached on the upper surface of the center of the recession 11 of the supporter 10. The form 20 has two surfaces 22, 23 to form a knife edge 21 which are polished to a mirror surface of lambda/10 or less and the surface of the form 20 is coated with a high melting point metal such as tungsten or molybdenum. The form 20 is attached on the upper surface of the supporter 10 brazed at an oblique area 30. Since the knife edge 21 which constitutes each side of an aperture 50 is made of diamond, machining accuracy can be made extremely high and exposure accuracy can be improved since the area irradiated by a beam is highly heat-resistant diamond. |
