Lear Siegler, Inc.

Smiths Industries Plc

Sli Avionic Systems Corp.

Harry L Gubbins

Jerry L Page

Ronald J Fredricks

Thomas E Perfitt

Daniel L Sugarbaker

Gordon P Eckley

Wilbur A Carrington

A triad sensor apparatus (300) comprises a passive ring Sagnac interferometric arrangement having a light source circuit (308) and a series of three multi-turn fiber optic rings (302, 304, 306). An optics/modulator circuit (312) is adapted to selectively switch optical waves emitted from the light source circuit (308) and transmit the signals through the corresponding fiber optic rings as counterpropagating optical waves. Nonreciprocal phase modulation is applied to the counter-propagating waves, and the waves are recombined so as to produce a 'zero order' fringe pattern having an intensity varying in accordance with the relative phase between the counterpropagating waves. Optical waves from the light source circuit (308) are selectively applied to a ring path during a given time period, while the photodetector circuit (324) is detecting light waves which have emerged from another ring path during the same given time period. Certain of the circuit components associated with signal processing circuitry (328) are selectively timed-shared with respect to signals associated with each of the gyroscope channels.

Integrated triad optical rate sensor apparatus

An optical rate sensor (200) is disclosed for use in inertial reference systems to measure rates of angular rotation with substantially high resolution and sensitivity. The sensor (200) comprises a passive ring Sagnac interferometer (201) with a multiturn fiber optic ring (232) through which counter-propagating optical waves are transmitted. A nonreciprocal time variant phase modulation is applied to the waves along with periodic effective transposition of ring ports. The waves are combined to produce a 'zero order' fringe pattern having an intensity varying in accordance with the relative phase between the counter-propagating waves. An intensity signal is derived from the fringe pattern having a phase offset corresponding to the Sagnac induced phase shift which in turn is linearly proportional to the angular rotation rate of the passive ring. Sampling, averaging and estimation circuits detemine the offset by detecting zero-crossing locations of the signal.

Optical rate sensor

Growing community of inventors

Grand Rapids, MI, United States of America

Harry L Gubbins