Mechanical characterization of planar springs for compact radiation pressure power meters

摘要

Counter to conventional methods of measuring laser optical power, radiation pressure-based power meters operate by reflection rather than absorption. This provides an opportunity for in situ, non-destructive total beam power measurement. Compact radiation pressure power meters designed to operate between a few tens and a few thousands of watts consist of a planar millimeter-scale spring-electrode-mirror component that deflects under radiation pressure from an incident beam. Spring constant, resonant frequency, and quality factor of microfabricated springs as well as coating-induced straining of the spring are the focus of this manuscript. We compare finite element models of the mechanical component with various measurements to inform future designs.