The world’s smallest known high temperature pressure sensor is a mere 125 microns in diameter and can function at temperatures as high as 700° C. Currently available sensors are limited to use in temperatures as high at 500° C.
Developed by Yizheng Zhu, a Ph.D. student in the Center for Photonics Technology (CPT), the sensor is fabricated directly on the tip of a fiber by micromachining and thermal fusion, giving it the same thickness as the optical fiber.
The sensor has minimal cross-sensitivity to temperature, resulting in a simplified sensor system with a wide temperature range. Its small size and low mass give the sensor an extremely high resonant frequency, resulting in a flat response over a very wide range of frequencies.
Sensitivity can be adjusted for different applications, with a pressure range as low as a few psi or as large as 10,000 psi. The sensor is another step toward CPT’s goal of developing pressure sensors that can operate above 1000°.