VIBRATION TRANSDUCER USING AN OPTICAL CAVITY COMPRISING BIREFRINGENT MIRRORS

We have developed an optical-cavity system comprising birefringent mir rors for a vibration transducer. To obtain a dispersive-shape signal n ecessary for reading out the information of mirror vibration, ne measu re the polarization change of the cavity transmission light caused by the natural birefringence appearing on interferential mirrors; this ef fect is enhanced by the cavity resonance. Since there are no additiona l polarization-changing elements inside the cavity, we can achieve the high finesse that is indispensable for a highly sensitive vibration m easurement. The principle and an experimental demonstration of the sys tem are reported here. (C) 1998 Optical Society of America.