Abstract: A partially-insulated cathode for exciting plasma in a plasma chamber is provided. The partially-insulated cathode includes a conductive structure enclosing a cavity having a cavity surface and an insulating material contiguously covering a portion of the cavity surface from the cavity opening up to an insulation height that is less than a cavity height. Cross-sections of the cavity in X-Y planes have at least one respective cavity-width. A cavity opening has a diameter less than a minimum cavity-width of the at least one cavity-width.

Abstract: A partially-insulated cathode for exciting plasma in a plasma chamber is provided. The partially-insulated cathode includes a conductive structure enclosing a cavity having a cavity surface and an insulating material contiguously covering a portion of the cavity surface from the cavity opening up to an insulation height that is less than a cavity height. Cross-sections of the cavity in X-Y planes have at least one respective cavity-width. A cavity opening has a diameter less than a minimum cavity-width of the at least one cavity-width.

Abstract: A ring laser gyroscope comprises a laser block that defines an optical closed loop pathway configured to contain a lasing gas. A plurality of mirror structures are respectively mounted on the laser block, with each of the mirror structures having a respective reflective surface that is in optical communication with the optical closed loop pathway. A plurality of electrodes are coupled to the laser block, with the electrodes configured to generate a pair of counter-propagating laser beams from the lasing gas in the optical closed loop pathway. At least one optical sensor is coupled to one of the mirror structures, with the optical sensor in optical communication with the closed loop pathway. A polarizer is in optical communication with the optical sensor. The polarizer is configured to pass laser light having substantially one polarization mode to the optical sensor.

Abstract: A partially-insulated cathode for exciting plasma in a plasma chamber is provided. The partially-insulated cathode includes a conductive structure enclosing a cavity having a cavity surface and an insulating material contiguously covering a portion of the cavity surface from the cavity opening up to an insulation height that is less than a cavity height. Cross-sections of the cavity in X-Y planes have at least one respective cavity-width. A cavity opening has a diameter less than a minimum cavity-width of the at least one cavity-width.

Abstract: Systems and methods for fabricating capacitive discharge electrodes for a ring laser gyroscope are disclosed. In one example, a laser block for generating a laser in a closed loop path comprises a laser block, wherein an optically closed loop path is formed within the laser block. Additionally, at least two electrodes are formed on the laser block, wherein the at least two electrodes are used in conjunction with a radio frequency power supply to create an electric potential in the laser block which generates at least one laser beam in the closed loop path. The at least two electrodes are manufactured by placing a paste composition on the laser block and securing the paste composition to the laser block. The paste composition also includes a conductive material.

Abstract: A ring laser gyroscope comprising: a ring laser gyroscope block comprising an optical cavity filled with a gain medium, the optical cavity having at least three legs that form an optical path; a radio frequency coupler positioned along the optical path, wherein the radio frequency coupler is configured to transmit radio frequency energy which causes two counter-propagating laser beams to form from the gain medium, the laser beams propagating around the optical cavity through the optical path formed by the at least three legs of the optical cavity; a gas flow bypass configured to connect at least one of the at least three legs to at least one other leg of the at least three legs.

Abstract: A ring laser gyroscope comprises a laser block that defines an optical closed loop pathway configured to contain a lasing gas. A plurality of mirror structures are respectively mounted on the laser block, with each of the mirror structures having a respective reflective surface that is in optical communication with the optical closed loop pathway. A plurality of electrodes are coupled to the laser block, with the electrodes configured to generate a pair of counter-propagating laser beams from the lasing gas in the optical closed loop pathway. At least one optical sensor is coupled to one of the mirror structures, with the optical sensor in optical communication with the closed loop pathway. A polarizer is in optical communication with the optical sensor. The polarizer is configured to pass laser light having substantially one polarization mode to the optical sensor.

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: A retaining clip for a getter is provided. The retaining clip for a getter includes a curved structure including a first surface, a second surface opposing the first surface, a first-edge surface, and a second-edge surface opposing the first-edge surface, the curved structure curved in a major curve having a major radius-of-curvature and a major axis perpendicular to the major radius-of-curvature; and at least one tab seamlessly extending from at least one of the first-edge surface and the second-edge surface. The curved structure is configured to be operably retained in a getter cavity with the getter that is attached to the at least one tab.

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: A method of protecting a surface of a device from residual polishing compound comprises applying a thin barrier layer of coating material to the surface of the device; polishing the surface with a polishing compound; rinsing the polishing compound from the device; and removing the thin barrier layer from the surface of the device to remove the residual polishing compound.

Abstract: An improved resonator fiber-optic gyro (RFOG). An example RFOG includes a closed-coil resonator where counter-propagating laser beams are done by fiber couplers. Signals are extracted from the ring resonator using other fiber couplers. The fiber couplers may be fiber spliced couplers, free-space fiber-to-fiber coupling elements or comparable coupling devices. A silicon structure may be used to align components of the gyro or just the coupling elements. The resonator includes a hollow-core fiber.

Abstract: A gas discharge tube, such as a ring laser gyroscope, includes a block, a cathode, and an anode. At least a portion of the block is maintained at a reference potential. The cathode may be biased at a higher potential than the reference potential, and the anode may be biased at a higher potential than the cathode. Alternatively, the cathode may be biased at a lower potential than the reference potential, and the anode may be biased at a higher potential than the reference potential. These biases enhance the flow of negative oxygen ions and impede the flow of positive alkali ions to increase sputter life of the gas discharge tube. Additionally or alternatively, a biasing electrode may be applied to the block to overlie the plasma supporting passage between the cathode and the anode. The biasing electrode has a bias to attract positive alkali ions.

Abstract: Described are methods for processing optical materials, by use of cleaning materials that include acid and oxidizer.

Abstract: A getter is a porous sintered metallic alloy used to absorb non-inert gases. The getter is placed in a getter well of a ring laser gyroscope system or other gas discharge system. The getter well is any enclosure in which a getter resides. The getter absorbs oxygen, which may be needed by some gyroscope components to operate. By restricting the gas flow into the getter well or by placing a diffusion barrier on the getter material, the getter may absorb non-inert gas at a slower rate.

Abstract: A getter is a porous sintered metallic alloy used to absorb non-inert gases. The getter is placed in a getter well of a ring laser gyroscope system or other gas discharge system. The getter well is any enclosure in which a getter resides. The getter absorbs oxygen, which may be needed by some gyroscope components to operate. By restricting the gas flow into the getter well or by placing a diffusion barrier on the getter material, the getter may absorb non-inert gas at a slower rate.

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: A getter is a porous sintered metallic alloy used to absorb non-inert gases. The getter is placed in a getter well of a ring laser gyroscope system or other gas discharge system. The getter well is any enclosure in which a getter resides. The getter absorbs oxygen, which may be needed by some gyroscope components to operate. By restricting the gas flow into the getter well or by placing a diffusion barrier on the getter material, the getter may absorb non-inert gas at a slower rate.

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: A gas discharge tube, such as a ring laser gyroscope, includes a block, a cathode, and an anode. At least a portion of the block is maintained at a reference potential. The cathode may be biased at a higher potential than the reference potential, and the anode may be biased at a higher potential than the cathode. Alternatively, the cathode may be biased at a lower potential than the reference potential, and the anode may be biased at a higher potential than the reference potential. These biases enhance the flow of negative oxygen ions and impede the flow of positive alkali ions to increase sputter life of the gas discharge tube. Additionally or alternatively, a biasing electrode may be applied to the block to overlie the plasma supporting passage between the cathode and the anode. The biasing electrode has a bias to attract positive alkali ions.