Driver for optical deflector using two asyncronous saw-tooth drive voltages and method for setting the same

摘要

An optical deflector includes a mirror, a movable frame for supporting the mirror, a support body surrounding the movable frame, and a first group of piezoelectric actuators and a second group of piezoelectric actuators alternating with the first group of piezoelectric actuators. A driver applies a first drive voltage having first saw-tooth waves to the first group of piezoelectric actuators, and applies a second drive voltage having second saw-tooth waves opposite in phase with the first saw-tooth waves to the second group of piezoelectric actuators. A difference in phase between the first and second saw-tooth waves is a predetermined value to suppress resonation of harmonic frequency components of the first and second drive voltages with a natural frequency of a mechanically-vibrating system of the mirror with respect to the axis thereof depending upon the piezoelectric actuators.

主权项

1. A driver for driving an optical deflector which comprises:
a mirror; a movable frame for supporting said mirror; a support body surrounding said movable frame; and a first group of piezoelectric actuators serving as cantilevers and a second group of piezoelectric actuators serving as cantilevers alternating with said first group of piezoelectric actuators, wherein said piezoelectric actuators are folded at every actuator and connected from said support body to said movable frame, each of said piezoelectric actuators being in parallel with one axis of said mirror, wherein said driver generates a first drive voltage having first saw-tooth waves and applies said first drive voltage to said first group of piezoelectric actuators, wherein said driver generates a second drive voltage having second saw-tooth waves opposite in phase with said first saw-tooth waves, and applies said second drive voltage to said second group of piezoelectric actuators, and wherein a difference in phase between said first and second saw-tooth waves is a predetermined value to suppress resonation of harmonic frequency components of said first and second drive voltages with a natural frequency of a mechanically-vibrating system of said mirror with respect to said axis thereof depending upon said piezoelectric actuators.