ABSTRACT
A. Fiber-Optic Sensors Fiber-optic sensors have some significant advantages: for example, freedom from electromagnetic interference, flexibility, low signal attenuation, rugged structure and smaller physical sizes compared wi th conventional optical system, and poten tially high accuracy. Probably the most important fiber-optic position sensors is the fiber-optic interferometer. Compared wi th a conventional interferometer, a fiber-optic interferometer has the advantages of, for example, much smaller physi cal size, stable performance (less sensitive to environmental conditions such as vibrations), and ease o f assembly.