Abstract: A system is provided, the system including at least one integrated optical circuit (IOC) formed from at least one material, and a support-structure configured to support the at least one IOC to couple light between other components. A performance of the at least one IOC is improved by treatment with at least one selected gas.

Abstract: A system is provided, the system including at least one integrated optical circuit (IOC) formed from at least one material, and a support-structure configured to support the at least one IOC to couple light between other components. A performance of the at least one IOC is improved by treatment with at least one selected gas.

Abstract: Systems and methods for thermal gradient compensation for ring laser gyroscopes are provided. In one embodiment, a method for producing bias compensated angular rate measurements from a ring laser gyroscope comprises: sampling an angle measurement output from a laser block sensor to obtain an angular rate measurement; obtaining an laser block temperature measurement (Tblock) for the laser block sensor; obtaining a temperature gradient measurement (Tdiff) for at least one gradient line across a portion of the laser block sensor; calculating a rate bias error by applying parameters produced from the temperature measurement (Tblock) and the temperature gradient measurement (Tdiff) to a thermal gradient compensation model, wherein the thermal gradient compensation model includes at least one coefficient corresponding to the temperature gradient measurement (Tdiff); and calculating a difference between the angle rate measurement and the rate bias error to produce a bias compensated angular rate measurement.

Abstract: Systems and methods for thermal gradient compensation for ring laser gyroscopes are provided. In one embodiment, a method for producing bias compensated angular rate measurements from a ring laser gyroscope comprises: sampling an angle measurement output from a laser block sensor to obtain an angular rate measurement; obtaining an laser block temperature measurement (Tblock) for the laser block sensor; obtaining a temperature gradient measurement (Tdiff) for at least one gradient line across a portion of the laser block sensor; calculating a rate bias error by applying parameters produced from the temperature measurement (Tblock) and the temperature gradient measurement (Tdiff) to a thermal gradient compensation model, wherein the thermal gradient compensation model includes at least one coefficient corresponding to the temperature gradient measurement (Tdiff); and calculating a difference between the angle rate measurement and the rate bias error to produce a bias compensated angular rate measurement.

Abstract: Systems and methods for improved ring laser gyroscope devices through mix ratio optimization are provided. In one embodiment, a ring laser gyroscope device comprises: a laser block assembly having a cavity therein that defines a ring shaped laser beam path around the laser block assembly, the cavity containing a fill gas mixture comprising Helium and Neon, wherein the laser block assembly is characterized as having a Neon depletion life limiter; and a readout assembly optically coupled to the laser block assembly. The readout assembly outputs a laser intensity monitor (LIM) voltage that represents optical energy within the cavity. The fill gas mixture has a Helium to Neon ratio richer in Neon than a ratio that would produce a peak LIM voltage from the readout assembly.

Abstract: A method for maintaining measurement accuracy of a ring laser gyroscope is disclosed. The method involves periodically measuring a path length control voltage in the ring laser gyroscope over a prescribed temperature range. When a first path length controlled by the path length control voltage deviates at least one wavelength from a nominal path length, the method detects the change in the path length as a mode shift. For each mode shift, the method applies a path length correction to maintain the first path length at a target path length over the prescribed temperature range. The method can apply a correction to a measurement signal output of the ring laser gyroscope by adjusting a calibrated scale factor depending on an actual integer number of wavelengths achieved during a mode shift.

Abstract: A method for maintaining measurement accuracy of a ring laser gyroscope is disclosed. The method involves periodically measuring a path length control voltage in the ring laser gyroscope over a prescribed temperature range. When a first path length controlled by the path length control voltage deviates at least one wavelength from a nominal path length, the method detects the change in the path length as a mode shift. For each mode shift, the method applies a path length correction to maintain the first path length at a target path length over the prescribed temperature range. The method can apply a correction to a measurement signal output of the ring laser gyroscope by adjusting a calibrated scale factor depending on an actual integer number of wavelengths achieved during a mode shift.

Abstract: A gas discharge tube such as a ring laser gyroscope includes a block. A cathode has an inwardly extending foot that engages the block. Additionally, or alternatively, an insulator is arranged to inhibit shorting between plasma in the block and a flange of the cathode.

Abstract: Current control biasing of a ring laser gyroscope is employed to protect electrode seals. A frame of a ring laser gyroscope has more than one electrode attached to it. An electric field is created between the electrodes during the operation of the gyroscope, which causes ions in the frame to migrate towards a lowest electrical potential. Electrode seals are located between the electrodes and the frame. By providing a positive power supply voltage and connecting the current control to the non-ground side of the power supply, the mounting structure may be at the lowest electrical potential. The ions will then migrate towards the mounting structure, which significantly reduces migration to the electrodes.

Abstract: A ring laser gyro having a high temperature seal. The ring laser gyro includes a laser block of known construction having a closed loop passage formed within the block in the shape of a polygon. Mirrors positioned at the intersection of each side of the polygon-shaped closed loop passage create an optical closed loop path through passage. A lasing gas is sealed within the closed loop passage, and electrodes mounted to the block and in fluid communication with the passage create at least one laser that traverses the optical closed loop path in the passage. The electrodes are mounted on the laser block with a high temperature seal comprising a washer having a low coefficient of thermal expansion and an optical bond between the washer and the laser block In a preferred embodiment, the laser block and the washer are formed from the same material to ensure that these structures expand at substantially the same rate when the ring laser gyro is used in a high temperature application.

Abstract: A ring laser gyro having a high temperature seal. The ring laser gyro includes a laser block of known construction having a closed loop passage formed within the block in the shape of a polygon. Mirrors positioned at the intersection of each side of the polygon-shaped closed loop passage create an optical closed loop path through passage. A lasing gas is sealed within the closed loop passage, and electrodes mounted to the block and in fluid communication with the passage create at least one laser that traverses the optical closed loop path in the passage. The electrodes are mounted on the laser block with a high temperature seal comprising a washer having a low coefficient of thermal expansion and an optical bond between the washer and the laser block. In a preferred embodiment, the laser block and the washer are formed from the same material to ensure that these structures expand at substantially the same rate when the ring laser gyro is used in a high temperature application.

Abstract: Current control biasing of a ring laser gyroscope is employed to protect electrode seals. A frame of a ring laser gyroscope has more than one electrode attached to it. An electric field is created between the electrodes during the operation of the gyroscope, which causes ions in the frame to migrate towards a lowest electrical potential. Electrode seals are located between the electrodes and the frame. By providing a positive power supply voltage and connecting the current control to the non-ground side of the power supply, the mounting structure may be at the lowest electrical potential. The ions will then migrate towards the mounting structure, which significantly reduces migration to the electrodes.

Abstract: A gas discharge tube such as a ring laser gyroscope includes a block. A cathode has an inwardly extending foot that engages the block. Additionally, or alternatively, an insulator is arranged to inhibit shorting between plasma in the block and a flange of the cathode.

Abstract: Plasma is placed in ring laser gyro blocks to create laser beams for the operation of the ring laser gyro. The plasma is doped with a small portion of material that allows the ring laser gyro to operate for a long period of time.

Abstract: A circuit for controlling the run current in a ring laser gyro includes circuitry for sensing temperature, supplying a current to the ring laser gyro and controlling the current supplied to the ring laser gyro and the current varies depending on the temperature. The current changes at predetermined temperature points.

Abstract: In an ring laser gyro, a path length modulation signal is applied to an amplifier with two gain levels and the amplifier's output is added to a path length transducer drive signal that changes the gyro's path length. When a path length reset signal is produced, the higher gain signal is selected and maintained for a short interval after the reset signal.

Abstract: A output mirror with a substrate that is doped with a radiation stabilizing material is used to reduce the adverse effects of long periods of exposure to radiation. The output mirror is capable of maintaining its transmissive characteristics when exposed to radiation and is used in radiation environments.

Abstract: A method performed during the processing of a ring laser gyro (RLG) will produce a long life in the RLG. The method includes filling the RLG with a gas mixture. A current is discharged within the RLG which will create certain reactions to condition the RLG for a long life.

Abstract: Mirrors are tested separately at different distances to plasma in separate ring laser gyros. Testing mirrors a predetermined distance away from plasma in the gyros allows accelerated testing of the environment of the mirrors in gyros. The test results are graphed to also allow prediction of ring laser gyro life.

Abstract: An integrator in a ring laser gyro that produces an output for changing the path length is reset synchronously with a gyro dither signal to reduce gyro errors from the dithering operation during the reset.