Abstract: A pump light source provides pump light to an optical fiber arranged to guide the pump light to a first optical isolation device. Light output by the first optical isolation device is input to a wavelength division multiplexer. A gain fiber is connected to the wavelength division multiplexer and arranged to be optically pumped by the pump light such that the gain fiber emits broadband light that propagates to the wavelength division multiplexer. An output optical fiber is connected to the wavelength division multiplexer and arranged to guide a portion of the broadband light emitted by the gain fiber to a second optical isolation device for input to a fiber optic rotation sensor.

Abstract: The invention is a focusing polarization rotator for use in the resonant mirror system of a ring laser gyroscope. The focusing polarization rotator accomplishes the traditional task of rotating the plane of polarization of a light beam that passes through it and at the same time performs a focusing function on the light rays. In a resonant mirror system, the device acts to constrain the transverse dimensions of light beams that follow the closed light-beam path established by the resonant mirror system thereby obviating the need for one or more curved mirrors that usually perform this function. The focusing polarization rotator is a wedge-shaped lens made from either a magneto-optic transparent material with a magnetic field within the lens or a material having different indices of refraction for left- and right-circularly-polarized light. The wedge shape of the lens greatly improves the bias stability of the RLG in which it is used.

Abstract: A system for performing scale factor stabilization of a broadband optical signal source used in fiber optic gyroscopes in radiation environments. An optical signal source is provided comprising a pump light source and an optical fiber arranged to receive pump light from the pump light source. Light output from the optical fiber is input into a wavelength division multiplexer. An optical gain fiber having an erbium-doped core is connected to the wavelength division multiplexer and arranged to be optically pumped by the pump light such that the gain fiber emits broadband light that propagates to the wavelength division multiplexer. An output optical fiber is connected to the wavelength division multiplexer and arranged to guide a portion of the broadband light emitted by the gain fiber to a fiber optic gyroscope. A filter device is positioned in-line with the broadband light emitted by the gain fiber to attenuate light outside of the bandwidth of the filter device.

Abstract: Disclosed herein is a multi-pole magnetic geometry for a multi-oscillator ring laser gyroscope. Multi-pole magnetic geometry configurations are disclosed which are useful for providing Faraday rotation where the multi-oscillator uses a Faraday rotator and high magnetic field effect where the nature of the multi-oscillator ring laser gyroscope is of split gain configuration. The multi-post magnetic geometry includes a plurality of top or bottom loaded diametrically opposed north and south pole axially directed magnets which are positioned substantially transverse to the optical pathway but suitable for providing axially directed magnetic fields to portions of the optical pathway only where desired. The multi-pole magnetic geometry disclosed herein substantially produces a magnetic flux that is restricted in its position to localized portions of the optical pathway with low far field effects.

Abstract: Disclosed herein is an External Scatter Removal System for Ring Laser Gyroscopes (such as a Split Gain Multioscillator) comprising a prism mounted on an optoisolator, wherein light transmitted out at least one of the mirrors of the Gyroscope passes into the prism and detector system, while oppositely directed backscattered light from the prism components is not returned to the gyroscope frame's internal optical path, thereby limiting any appreciable backscatter from interfering with an accurate measurement of the rotation rate of the gyroscope.

Abstract: A triaxial multioscillator for operation in accordance with a mode of operation requiring the imposition of a substantially uniform axial magnetic field on the gain region of each lasing cavity. An integral frame of glass ceramic material has a rhombic dodecahedral shape and includes three closed lasing cavities, each formed of four straight segments. The cavities include three mutually parallel segments, one from each cavity, that are regularly spaced on a circle perpendicular to the axis of the frame. An internal cathode and six anodes are associated with the frame to provide gain in each of such three segments. The frame is positioned within a closed cylindrical element of soft iron composition by means of a fixture. The fixture positions magnets adjacent the top and bottom of the element to generate parallel lines of magnetic flux therein.

Abstract: A method and apparatus for optical pumping of an NMR cell by means of laser light. A current driver provides an a.c. current waveform as injection current to a laser diode. The resulting laser intensity spectrum closely approximates the absorption spectrum of the cell to thereby increase the signal generated for a given power input.