Abstract: A system having a multiple-mirror ring-down cavity with one mirror where light may be input into the cavity and light from the cavity may be detected. A valve may permit light to enter or not to enter the cavity. An amplifier may be connected to a detector for detecting light from the cavity. The amplifier may be off or set at a low gain when light is entering the cavity and be on at a medium or high gain at a time when light is not entering the cavity.

Abstract: A system having a multiple-mirror ring-down cavity with one mirror where light may be input into the cavity and light from the cavity may be detected. A valve may permit light to enter or not to enter the cavity. An amplifier may be connected to a detector for detecting light from the cavity. The amplifier may be off or set at a low gain when light is entering the cavity and be on at a medium or high gain at a time when light is not entering the cavity.

Abstract: Ring laser gyroscope that includes a gyroscope block, a radio frequency transmitting device, and a radio frequency energy source. The gyroscope block has at least one discharge bore containing a gain medium, and the radio frequency transmitting device is located within the gyroscope block in proximity to at least one discharge bore and located so as to encompass the discharge bore. The radio frequency energy source is configured to apply a pulsed radio frequency signal to the transmitting device.

Abstract: A sensitive fluid sensor for detecting fluids and particularly trace fluids. The sensor may be adjustable for detecting fluids of various absorption lines. To effect such adjustment, a tunable laser may be used. The laser may non-tunable with a cavity having moveable mirror(s) for tuning. The laser may be an edge emitting diode, a VCSEL or other tunable on on-tunable source. The detection apparatus of the sensor may incorporate a sample cell through which a laser light may go through. The sample cell may include a tunable ring cavity block. There may be a photo detector or detectors proximate to the ring cavity. The lasers and detectors may be to electronics and/or a processor.

Abstract: A ring laser gyroscope is described which includes a gyroscope block, a radio frequency transmitting device, and a radio frequency energy source. The a gyroscope block has at least one discharge bore containing a gain medium, and the radio frequency transmitting device is located within the gyroscope block in proximity to at least one discharge bore and located so as to encompass the discharge bore. The radio frequency energy source is configured to apply a pulsed radio frequency signal to the transmitting device.

Abstract: A ring laser gyroscope is described which includes a laser cavity configured to provide an optical laser path for a pair of counter-propagating laser beams, an optical sensor configured to receive a portion of the energy from the counter-propagating laser beams, and a unit configured to receive outputs from the optical sensor. The unit is configured to utilize the output to generate at least a residual path length control signal, a laser intensity monitor signal, and readout signals.