Abstract: A method and apparatus for producing preferential polarization of the output light beam from a laser of the kind having a three surface retroreflector comprises mounting the three reflecting surfaces of the retroreflector so that the surfaces are orthogonal in the retroreflector. The preferential polarization is obtained by controlling the combined effects of the orientation of the retroreflector assembly, with respect to the axis of the beam, and the selection of the coatings on the three reflecting surfaces.

Abstract: A fast axial flow folded laser includes a vessel which houses heat exchangers and a pump which imparts the pumping action throughout the laser. Only one housing is necessary and this housing can also be used as an optical bench for the resonator. In one embodiment a positive displacement rotary pump is utilized and a retroreflector included to mount three fold mirrors. In the folded configuration the retroreflector provides angular stability in any two orthogonal planes parallel to the laser beam.

Abstract: A sealed rotary compressor is provided which includes separate pump and gear chambers. Disposed within the pump chamber is a set of rotors operatively associated with a set of gears rotatably mounted within the gear chamber. A substantially pressure differential exists between the two chambers. Rotational power is applied directly to the rotors through a static seal rather than through the gears which are utilized primarily to transmit the dynamic load. The pump chamber is defined by two end plates with a surrounding thin-walled housing. Within the pump chamber are interior thin wall members with the rotary members disposed therebetween and defining inlet and outlet pockets operatively associated with a pump housing inlet and outlet means.