A High-Performance, Low-Cost Laser Shutter using a Piezoelectric Cantilever Actuator

Abstract

We report the design and characterization of an optical shutter based on a piezoelectric cantilever. Compared to conventional electro-magnetic shutters, the device is intrinsically low power and acoustically quiet. The cantilever position is controlled by a high-voltage op-amp circuit for easy tuning of the range of travel, and mechanical slew rate, which enables a factor of 30 reduction in mechanical noise compared to a rapidly switched device. We achieve shuttering rise and fall times of 11 $\mu$s, corresponding to mechanical slew rates of 1.3 $\textrm{ ms}^{-1}$, with an timing jitter of less than 1 $\mu$s. When used to create optical pulses, we achieve minimum pulse durations of 250 $\mu$s. The reliability of the shutter was investigated by operating continuously for one week at 10 Hz switching rate. After this period, neither the shutter delay or actuation speed had changed by a notable amount. We also show that the high-voltage electronics can be easily configured as a versatile low-noise, high-bandwidth piezo driver, well-suited to applications in laser frequency control.