Laser autocollimator using optical parasitic interference

Abstract

A laser autocollimator assembly that provides an objective, unambiguous, and simple means to achieve precise (for example, arc second or sub arc-second) alignment between the laser autocollimator assembly and a reference surface. The laser autocollimator assembly relies on optical parasitic interference between a reflected beam from the reference surface and the laser beam in the laser cavity that, when alignment is achieved, results in a disruption of the action of the laser, resulting in a reduction in the output power level of the laser beam. By monitoring the power level of the laser beam, for example monitoring the power level of the reflected beam, it can be determined that alignment has been achieved when the power level of the laser beam has been reduced to a minimum level. The power level can be automatically monitored, thereby eliminating the need for user interpretation.

Dependencies are inferred from the claim text.