Study on a novel optical fiber pressure sensor

Abstract

A novel kind of micromachined fiber-optic pressure sensor is developed. This paper describes our progress in the development of the novel, MEMS based, high-sensitivity, high-resolution, high-temperature and fast-response optical fiber pressure sensor for pressure measurement in unsteady and turbulent flow fields system. The development process includes design, simulation, fabrication and package of the sensor is demonstrated The pressure sensor is fabricated by deep reactive ion etching (RIE) technology. The finished device has a sensing element with a size of 100 /spl mu/m in diameter. It has been expected - through ANSYS simulation, to show good sensitivity, wide measuring scale, as well as high frequency response. The fiber optic pressure sensor measurement system is based upon the interferometric response of an extrinsic cavity formed between the interrogation fiber and a reflective silicon diaphragm. We discussed the design trade offs, optical interrogation and temperature sensitivity of such a configuration, and demonstrate the success of the design in small-scale shock tube experiments. We then describe the application of the sensor in a full-scale turbine test facility in which pressure signals with frequency components exceeding 50 kHz were obtained.