| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an optical gyro which has a small insertion loss at a light extracting part, a small oscillation threshold and a wide allowance range for assembly errors. SOLUTION: A light extracted from a laser mode 19 in the counterclockwise direction by a directional coupler 12 is emitted from a light extracting part 14. A light extracted from a laser mode 18 in the clockwise direction by the directional coupler 12 is emitted from a light take part 15 after deflected by a total reflection mirror 13. Optical waveguides of these light extracting parts similar to the directional couplers are provided having an optical gain by injecting a current, thereby compensating for the absorption loss. The light extracting parts 14 and 15 are directed slightly inwardly by with respect to a parallel position relation, whereby the intensity of light taken in the vicinity of photodetectors 16 and 17 is increased. Two output lights form interference fringes in the vicinity of the photodetectors 16 and 17. The interval between center of two photodetectors 16 and 17 is an (N/2+1/4) times (N is an integer) a pitch A of the interference fringe pattern.</p> |
