| 摘要 |
A two-dimensional laser beam scanning device having a support base and a piezoelectric bimorph structure comprising four consecutively bonded piezoelectric layers disposed in the support base. The two outer layers of the bimorph structure have a shorter length than the two inner layers, and the inner two layers extend lengthwise in one direction past the ends of the outer two layers to form a two-layer bimorph portion having a free end. The four-layer portion is affixed along a first lengthwise edge thereof to the support base. The other lengthwise edge defines a free edge. The free end of the two-layer portion is bent ninety-degrees. The two-layer portion has a different resonant frequency than the four-layer portion. The scanning device further comprises a mirror attached to the free end of the two-layer bimorph portion and electrode means for applying an electrical signal to the bimorph structure to cause the free edge of the four-layer portion and the free end of the two-layer portion to vibrate in orthogonal directions whereby light incident upon the mirror is simultaneously scanned in two orthogonal directions. The applied electrical signal has a first frequency component substantially equal to the resonant frequency of the four-layer portion and a second frequency component substantially equal to the frequency of the two-layer portion. Alternatively, the two dimensional scanning device comprises a piezoelectric bimorph having first and second free end regions disposed in orthogonal planes. First and second mirrors are attached to the first and second free end regions, respectively.
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