A self-excited chopper made by quartz micromachining and its application to an optical sensor

We report the successful self-excited operation of the monolithic optical chopper made of quartz. The chopper is oscillated through piezoelectric strain induced by electric field between meandering electrodes on the flexible suspensions. The piezoelectric signal from the deformed suspension is detected to control the amplitude of oscillation at constant magnitude. We also employed this chopper in an optical sensor as a mechanical component to regulate the incident laser-beam, and demonstrated chopper-amplification and demodulation.