| 摘要 |
PURPOSE:To obtain an optimum conduction for laser beam machining by bringing an inter-lens distance of a beam expander to variable control. CONSTITUTION:In a laser beam machine having a laser oscillator 1, a beam expander 4 and a condensing system, a distance between two pieces of incident side lens 41 and emitting side lens 42 for constituting the beam expander 4 is made variable, and an incident beam is emitted as an enlarged or reduced laser beam 2, curved vertically by a turn-back mirror 5, passes through a condensing lens 6 and forms a focal point 9 on a working object 7 on an working table 8. In such a way, by one set of laser beam machine, materials extending from a thin one to a thick one can be worked as an optimum beam spot diameter corresponding to its thickness. |
