ILLUMINATION OPTICAL SYSTEM, PATTERN DEFECT INSPECTION DEVICE USING IT AND OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To provide an illumination optical system capable of reducing illumination irregularities caused by coherence of laser light, without requiring a movable mechanism, without damaging utilization efficiency of an illumination light flux and without requiring enlargement of a device.;SOLUTION: This illumination optical system is equipped with an incident side lens array 9 for generating a plurality of pseudo light sources by converging illumination light from a laser light source part 1, an outgoing side lens array 10 facing to each element of an integrator 12, an optical fiber array body 11 formed by aligning a plurality of optical fibers 13 each of which has an incident face 13a facing to each lens element of the incident side lens array 9 and an outgoing face 10b facing to each lens element of the outgoing side lens array 10, and has a piezoelectric material coating 14 formed on the circumferential part 13c to thereby change its refractive index, and a control circuit 15 for controlling the piezoelectric material coating 14 of each optical fiber 13.;COPYRIGHT: (C)2005,JPO&NCIPI