| 摘要 |
PURPOSE:To make a titled modulator applicable to a wide range of frequency and to reduce the size thereof by constituting the modulator in such a manner that the coherent light projected to a mirror oscillated with a piezo-electric ceramic element and oscillation diaphragm is reflected by the mirror and is phase-modulated. CONSTITUTION:The thin piezo-electric ceramic element 24 made into a rectangular strip shape is affixed longitudinally to the side face of the oscillation diaphragm 22 and the mirror 25 is fixed to the upper part at the top end of the diaphragm 22. The mirror 25 is oscillated with the element 24 and the diaphragm 22 at the oscillation frequency of the diaphragm 22 when the voltage of a desired frequency is impressed to the electrode of the element 24 of such optical phase modulator 20. the reflected wave is modulated to an optical phase- modulated wave 27 and is thus reflected as the optical path length fluctuates periodically when the coherent light 26 is projected to the mirror 25. The element 24 oscillates according to the frequency of the impressed voltage and is therefore applicable to a wide range of frequencies. Since the shape and size of the diaphragm plate 22 are small, the reduction in the size over the entire part is made possible. |
