Abstract: An optical element for homogenizing and, possibly, concentrating the output from high-power two-dimensional semiconductor laser arrays, which has the basic shape of a convex-flat cylindrical lens with a facet cut into the convex surface for each individual semiconductor laser bar.

Abstract: An open loop liquid spray phase-change cooling system for a laser comprised of an expendable supply of a compressed liquid refrigerant, a laser heat sink, an on/off valve, and a means for controlling the on/off valve in response to the measured heat sink temperature.

Abstract: An HBr laser is pumped by a slave laser power oscillator which excites the (2,0) absorption band of the HBr laser, to cause it to lase around four microns. A tunable master oscillator, which is frequency locked to an HBr reference cell, seeds the slave oscillator and maintains lock-on to an absorption line in the (2,0) band of HBr.

Abstract: This improved rotary-type, super-abrasive grinding tool is designed to cope with a longstanding problem heretofore encountered when subjecting such tools to periodic dressing operations. The improved tool comprises an annular hub having a periphery or rim with a generally U-shaped slot therein, and a generally annularly-configured super-abrasive matrix supported in said slot and having an outer peripheral, configured working surface. The axially opposed walls of the slot buttress and support the sides of the super-abrasive matrix. Each of the walls have a plurality of peripherally-exposed, radially-disposed recesses therein containing a super-abrasive medium, preferably having the same composition and integral with the super-abrasive matrix. The exposed periphery of the super-abrasive medium protects peripherally-aligned portions of the rim from excessive wear when improperly contacted with the dressing medium.