Experimental investigation of a semiconductor ring laser as an optical gyroscope

Fundamental characteristics of a semiconductor ring laser (SRL) as an optic al inertial rotation sensor were reported. An SRL used for experiments had a small semiconductor gain block in a fiber external cavity, Beat frequency was measured by the terminal voltage change of an SRL as a function of the rotation rate, changing the loop radius of an SRL and the turn number of t he fiber loop for investigating the detection characteristics. Detection se nsitivity was proportional to the loop radius, and was independent of the t urn number of the fiber loop. These experimental results verified that SRL' s were operated as active ring laser gyroscopes based on the Sagnac effect. Furthermore, we verified that lock-in phenomenon was one of the most domin ant noise sources.