Abstract

Laser beams are usually unstable in terms of their pointing direction because of fluctuations of the resonant cavity. This angular fluctuation of laser beams can be somewhat reduced with a servomechanism.¹,² My approach uses an optical system capable of self-compensating the angular fluctuation of the laser. Because no servomechanism is required, the beam stabilizer reacts instantaneously. The stabilizer essentially uses the self-compensation principle. The input beam is first divided into two perpendicularly polarized beams, that then combine to form the output beam. Because the angular fluctuation of the input beam causes the two perpendicularly polarized component beams to deviate in exactly opposite directions, the angular error of the combined beam is automatically cancelled. This system works well for Gaussian beams, either cw or pulsed. The design and analysis of the proposed beam stabilizer are provided. Experimental demonstrations are also given.

© 1990 Optical Society of America