| 摘要 |
PURPOSE:To omit the use of two piezoelectric elements having the same voltage displacing characteristics and to attain the precise correction of plane turning by applying resiliency due to permanent magnets so that tensile force is not applied to a piezoelectric element at the contraction of the piezoelectric element. CONSTITUTION:A semiconductor laser light source 1 is fitted to a supporting body 2, the piezoelectric element 3 and a permanent magnet 4 are fitted to one end of the supporting body 2 and the other end respectively and a permanent magnet 4' is fitted to a fixing part so as to be opposed to the permanent magnet 4, so that resiliency due to the permanent magnets 4,4' is applied to the piezoelectric element 3 through the supporting body 2 and the supporting body 2 is displaced in a direction A-A' parallel with the rotary shaft 11 of a rotary polyhedral mirror 6. As the permanent magnets 4,4', an SmCo magnet having high coercive force, a ferrite magnet, or the like is used. The piezoelectric element 3 is displaced in accordance with the impressed control voltage to displace the semiconductor laser light 1 through the supporting body 2. Since a parallel light beam made incident on the mirror surface 6' of the rotary polyhedral mirror 6 is vertically displaced, face turning can be corrected. |
