The current state of the art of opticat fiber sensors is reviewed. The principles of operation are detaited and the various types of fiber sensors are outlined. Achievable performance and timitations are discussed and a description of technology used to fabricate the sensor is presented. The characteristics of acoustic, magnetic, gyro, laser diode, and other sensors are described. Trends in the development of this sensor technology and expected application areas are briefly outlined.

A method of homodyne demodulation using a phase generated carrier is described and experimentally demonstrated. The method has a large dynamic range, good linearity, and is capable of detecting phase shifts in the microradian range. The detection scheme obviates the phase tracker resetting problem encountered in active homodyne detection schemes. Two methods of producing the carrier are presented, one employing a piezoelectric stretcher, the other using current induced frequency modulation of the diode laser source. These two methods are compared. The origins of the noise Limiting the system are briefly discussed.

A method of homodyne demodulation using a phase generated carrier is described and experimentally demonstrated. The method has a large dynamic range, good linearity, and is capable of detecting phase shifts in the microradian range. The detection scheme obviates the phase tracker resetting problem encountered in active homodyne detection schemes. Two methods of producing the carrier are presented, one employing a piezoelectric stretcher, the other using current induced frequency modulation of the diode laser source. These two methods are compared. The origins of the noise Limiting the system are briefly discussed.

The current state of the art of opticat fiber sensors is reviewed. The principles of operation are detaited and the various types of fiber sensors are outlined. Achievable performance and timitations are discussed and a description of technology used to fabricate the sensor is presented. The characteristics of acoustic, magnetic, gyro, laser diode, and other sensors are described. Trends in the development of this sensor technology and expected application areas are briefly outlined.

We present our results on optical waveguides formed by thermal diffusion of ions in glass. It was found that the peak of the ion-exchanged region can be shifted into the substrate interior by limiting the diffusion process. We also found that low loss films (<0.1 dB/cm) can be fabricated using this process and that the modal losses in these films do not agree with those losses predicted by existing theories. Also, the ion-exchange process has proved to be a simple means for fabricating tapered-edge couplers.

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In single-mode optical fiber interferometer sensors environmental effects such as ambient temperature fluctuations and static pressure changes result in signal fading. Three different optical techniques which eliminate the signal fading problem are presented and experimentally verified. Comparison of the three techniques in terms of their technical merits is presented.