Symmetrical mandrel-type optical-fiber hydrophone probe of temperature drift resistance

Abstract

The invention relates to a symmetrical mandrel-type optical-fiber hydrophone probe of temperature drift resistance. The hydrophone probe comprises a sensitive portion end cap, a sensitive portion skeleton, a sensitive thin wall, a sensitive optical fiber, a sensibilization coating, a reference portion skeleton, a reference optical fiber, a reference portion sleeve, a reference portion end cap, anoptical-fiber water-tight joint, a fastening bolt, a first sealing ring and a second sealing ring. The reference portion skeleton and the sensitive thin wall have a same characteristic size and are symmetrical along an axial direction. When an environment temperature changes, length variable quantities of the reference optical fiber winding the reference portion skeleton and the sensitive opticalfiber winding the sensitive thin wall are equal so that a phase difference of the two is ensured to be constant. Compared with the prior art, by using an optical-fiber hydrophone of the invention, a defect that a demodulation signal is easy to be influenced by environment temperature changes is overcome, and reliability and measurement accuracy of the optical-fiber hydrophone are increased.

Description

technical field [0001] The invention belongs to the field of optical fiber hydrophones, in particular to a symmetrical mandrel type optical fiber hydrophone probe resistant to temperature drift. Background technique [0002] Optical fiber hydrophone is a new type of underwater acoustic signal detection sensor based on optical fiber sensing technology. It has significant advantages over traditional piezoelectric hydrophones in terms of sensitivity, frequency band, and anti-electromagnetic interference. As a key link in the demodulation process of interferometric fiber optic hydrophones, it is particularly important to accurately obtain the phase difference between the sensitive arm and the reference arm in the Michelson interferometer. For traditional fiber optic hydrophone probes, the environments and winding methods of the sensitive fiber and the reference fiber are slightly different, and the responses of the sensitive arm and the reference arm to temperature changes are o...

AI Technical Summary

Problems solved by technology

For traditional fiber optic hydrophone probes, the environments and winding methods of the sensitive fiber and the reference fiber are slightly different, and the responses of the sensitive arm and the reference arm to temperature changes are often out of sync, resulting in a phase difference between the two arms. Irregular drift related to temperature changes makes it difficult to guarantee the reliability and accuracy of demodulation results

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