ABSTRACT
The laser shutter is an optical and mechanical physical apparatus mounted at or near the output of a laser. It allows a beam to pass through unobstructed when commanded to open and safely terminates the specular beam with minimal backscatter when commanded to close. Closure takes place at the end of an operation or if the system experiences a safety breach. Well-engineered units provide a fail-safe closure on power loss or control signal loss. The beam is terminated by optical absorption inside the enclosure. A lightweight moving mirror system is used to steer the beam to the absorber, or beam dump, when in the closed position. The mirror and absorber optical properties must be rated for the demands of the laser irradiance. This separates a laser shutter from imaging-type shutters in cameras and vision systems and from rotary choppers. High reflectivity, high damage threshold mirrors, and high-absorption, ultra-low outgassing beam dumps are required in most laser shutters.
