LIGHT TRANSMISSIVE MEMBER FOR COVER OF OPTICAL DEFLECTOR, OPTICAL DEFLECTOR, OPTICAL LENS AND OPTICAL MIRROR

摘要

PROBLEM TO BE SOLVED: To provide a light transmissive member for cover of an optical deflector, which reduces speckle of laser light without increasing the number of optical elements arranged on an optical path.SOLUTION: An optical deflector 1 scans the reflection direction of laser light made incident to a mirror part 11 by oscillating the mirror part 11. A light transmissive member 5 for cover is mounted to the optical deflector 1. In the light transmissive member 5 for cover, on the surface of a portion making incident light and reflection light to the mirror part 11 penetrate, a speckle elimination pattern 17 is formed so that a sub-wavelength structure area, which has grooves arrayed repeatedly at a cycle shorter than the wavelength of used light and has structural birefringent, is arranged so as to have a portion where optical axis directions to be the array directions of the grooves are different from each other.SELECTED DRAWING: Figure 1