| 摘要 |
PURPOSE:To improve the sticking strength of a piezoelectric element and attain size reduction by sticking the piezoelectric element on the light incidence or projection surface of dielectric ceramics, and straining the element through piezoelectric effect and causing birefringence effect. CONSTITUTION:The piezoelectric element 2 is fixed on the light projection surface of the dielectric ceramics 1, and when a specific electric field is applied to the piezoelectric element 2 by an electric power source 5, the piezoelectric element has lateral piezoelectric effect to the electric field and the ceramics 1 where the piezoelectric element 2 is fixed is strained in its facial direction. Consequently, the polarization of the ceramics which is in random directions is arrayed in the straining direction to obtain optical anisotropy. Namely, light incidents to the ceramics surface is reflected double. The extent of the birefringence effect depends upon the extent of the polarization, so the voltage of the variable power source 5 is controlled to control the birefringence. |
