| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To machine a workpiece with high and consistent dimensional accuracy by preventing variance in the machining line width and the energy density due to deformation of irradiation spot of laser beam. <P>SOLUTION: Adjustment is made so that a spherical center 43 of a concave sphere 41a in a plano-concave lens 41 as a workpiece 8 placed on a machining stage 9 is coincident with an oscillating center 21 of the machining stage 9, and a machining shape 42a is machined by applying ultra-short pulsed laser beam 13 at an optional machining position 42 of a concave spherical surface 41a while oscillating the machining stage 9 in a state where the optical axis of the ultra-short pulsed laser beam 13 passes through the spherical center 43 (the oscillating center 21). In such a state, the optical axis of the ultra-short pulsed laser beam 13 is constantly matched with the normal at the machining position 42, the circular shape of the irradiation spot of the ultra-short pulsed laser beam 13 at the machining position 42 is not changed even by the oscillating scanning, the energy density is consistent, and any machining error of the machining shape 42a due to the change of the shape of the irradiation spot or the like can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
