摘要 |
In the present invention, a curvature variable reflector made from a material capable of elastically deforming in response to a fluid pressure is formed to a curved-face mirror by making use of a pressure by a fluid such as air so that a diameter of a laser beam coming into a converging optical member can be changed at a high speed step by step or smoothly. And by controlling the fluid pressure step by step or steplessly according to a type or thickness of a work, machining can always be performed with an appropriate laser beam diameter. |