Abstract: A modular unstable ring resonator utilizing several independent gain modules is used to obtain output of a multiple set of mutually coherent beams. Additionally, rigorous mutual coherence is maintained even when the system operates on more than one longitudinal mode or/and on more than one gain transition; specific frequency-control elements are eliminated; satisfactory operation is possible with one or more gain-medium modules disabled. Each segment of the ring resonator's optical path may contain a laser gain medium, an output mirror, and a beam expander for continuously circulating a portion of the system flux while also coupling out a portion of the flux from each output mirror. The plural outputs may be used individually or collectively.

Abstract: The mixing of high solids loaded propellants is accomplished under reduced viscosity conditions by employing near critical liquid (NCL) carbon dioxide as the processing fluid in a volume amount from about 10 to about 20 percent of the volume of the propellant ingredients.A typical propellant composition contains about 88 percent solids portion by weight comprised of ammonium perchlorate, aluminum powder, ballistic modifiers, and bonding agent and about 12 percent liquid portion by weight comprised of liquid polymers, plasticizers, and curatives.NCL carbon dioxide facilitates low viscosity mixing of propellant ingredients in a completely inert processing fluid. The method allows the entire mixing procedure to be conducted under reduced temperature conditions (e.g., 90.degree. F. vs 140.degree. F.), and thereby, provides for extended propellant pot life. Pressure mixing in a range of 760 psig to 1000 psig enables carbon dioxide to be maintained as a NCL to assist propellant mixing.

Abstract: A device for determining the direction of a neutral particle beam relative o a reference direction is provided. The technique of laser resonant fluorescence is used. Measurements are made near the doppler free angle and a direct view prism means is used for automatically compensating for small drifts in the laser frequency is used to insure that the most accurate alignment results are obtained even with laser frequency changes.

Abstract: A system for enhancing targets by rotating a polarized filter in front of a V tracker system to enable an operator to pick out and track targets more effectively from a cluttered background including trees, vegetation, and general landscape.

Abstract: A method of locating an electrostatic discharge event in a predetermined ucture by sensing electromagnetically that an electrostatic discharge event has occurred and producing a trigger signal from the electromagnetic sensing to control a recording device for the starting of time, utilizing a plurality of acoustic detectors about the structure for sensing the acoustic of the electrostatic discharge event, determining the time elapsed between the starting of time by the electromagnetic sensing and the signals sensed by the acoustic detectors and utilizing the information gained from the times sensed and the predetermined locations of the sensors to determine the location of the electrostatic discharge event in the predetermined structure.