Fiber-optic acceleration sensor based on the photoelastic effect.

A novel type of fiber-optic acceleration sensor was constructed of a photoelastic substance such as isotropic epoxy resin, DAP (diallylphthalate polymer), or LiNbO3 single crystal. By a weight placed on the upper surface of the rectangular rod of photoelastic material, stress-induced birefringence is brought about in response to vibrational acceleration. With this sensor, acceleration from 10−3 to 30 G was accurately measured in the frequency range from dc to 3 kHz.