OPTICAL SCANNER AND IMAGE FORMING APPARATUS FURNISHED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To control the resonance frequency of an oscillation body while avoiding an additional power consumption supplied from a power source in an optical scanner which scans with reflected light from a reflection face by swinging the oscillation body by swinging by oscillating around a swinging axis line on which a reflection face is formed on which the light is made incident. SOLUTION: The optical scanner includes: the oscillation body 124 having the reflection face 120; piezoelectric bodies 150 and 154 mounted on the oscillation body; a driving circuit 180 which drives the oscillation body at a driving frequency which is substantially the same as the resonance frequency of the oscillation body by supplying an electric charge to the piezoelectric bodies and thus torsionally oscillates the oscillation body around the swinging axis line. The optical scanner further includes: piezoelectric bodies 152 and 156 mounted on the oscillation body; and a resonance frequency control circuit 230 which controls the rigidity of the piezoelectric bodies by controlling the discharge quantity of the electric charge from the piezoelectric bodies, thus controls the resonance frequency of the oscillation body. COPYRIGHT: (C)2005,JPO&NCIPI