| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform auto-focusing, regardless of the reflecting state of a processing surface of a workpiece, without the switching of a measuring system of a displacement sensor or replacement of the displacement sensor. <P>SOLUTION: A focusing unit including an error amplifier 213 and a motor driver 214 adjusts the focal position of an objective lens 217, when a probe light is regularly reflected by the processing surface of the workpiece 102, based on a measurement result measured by the displacement sensor 211 using a reflected light of the regularly-reflected probe light which is diffusely reflected by a diffusive reflecting plate 212 and then reflected by the processing surface. The focusing unit adjusts the focal position of the objective lens 217, when the probe light is regularly reflected by the processing surface, based on a measurement result measured by the displacement sensor 211 using the diffusely-reflected light. The invention can be applied to a laser processing unit. <P>COPYRIGHT: (C)2013,JPO&INPIT |
