OPTICAL SCANNER AND ITS MANUFACTURING METHOD, OPTICAL WRITING DEVICE, IMAGE FORMING APPARATUS, VIBRATORY MIRROR CHIP AND ITS MANUFACTURING METHOD, AND OPTICAL SCANNING MODULE

摘要

PROBLEM TO BE SOLVED: To enable an optical scanner, which vibrates a mirror substrate reciprocally on a beam as an axis of torsional rotation, to make an optical scan with a stable beam shape. SOLUTION: On the reverse surface of the mirror substrate 101 where a mirror surface 115 is not formed, a rib 121 for reinforcement is formed which extends at right angles to at least beams 102 and 103, and the remaining area is a thin etched area. The rib 21 for reinforcement is provided to effectively suppress deformation of the mirror substrate 101 in vibration and then the flatness of the mirror surface 115 is maintained, so the optical scan with the stable beam shape can be made. Various styles of the rib for reinforcement like a rib provided surrounding the external edge of the mirror substrate are disclosed. Further, such a style that the mirror substrate is composed of a thin film and a frame body is also disclosed. COPYRIGHT: (C)2003,JPO