A Compact Optical MEMS Pressure Sensor Based on Fabry–Pérot Interference

Abstract

Pressure sensors have important prospects in wind pressure monitoring of transmission line towers. Optical pressure sensors are more suitable for transmission line towers due to its anti-electromagnetic interference. However, the fiber pressure sensor is not a suitable choice due to expensive and bulky. In this paper, a compact optical Fabry–Pérot (FP) pressure sensor for wind pressure measurement was developed by MEMS technology. The pressure sensor consists of a MEMS sensing chip, a vertical-cavity surface-emitting laser (Vcsel), and a photodiode (PD). The sensing chip is combined with an FP cavity and a pressure sensing diaphragm which adopts the square film and is fabricated by Silicon on Insulator (SOI) wafer. To calibrate the pressure sensor, the experimental platform which consists of a digital pressure gauge, a pressure loading machine, a digital multimeter, and a laser driver was set up. The experimental results show that the sensitivity of the diaphragm is 117.5 nm/kPa. The measurement range and sensitivity of the pressure sensor are 0–700 Pa and 115 nA/kPa, respectively. The nonlinearity, repeatability, and hysteresis of the pressure sensor are 1.48%FS, 2.23%FS, and 1.59%FS, respectively, which lead to the pressure accuracy of 3.12%FS.

Design and Development of a MOEMS Accelerometer Using SOI Technology

“…Dedicated micro-electro-mechanical system (MEMS) displacement sensors are microelectronic devices that are suitable for vibrational analysis. These sensors are designed to monitor mobile MEMS components using sensing principles such as capacitance [ 11 , 12 ], electromagnetics [ 13 , 14 ], photodiode-based principles [ 15 , 16 ], and lasers or optics [ 17 , 18 ]. Each sensing principle has its own advantages and disadvantages depending on the sensing mechanism used on the micro-scale.…”

“…In micro-opto-electro-mechanical system (MOEMS) sensors, the proof mass displacement changes the characteristics of the output light. They use several approaches, such as intensity-based detection, [ 3 , 16 , 19 ] fiber Bragg grating (FBG) [ 20 , 21 ], and Fabry–Pérot interferometry (FPI) [ 17 , 22 , 23 , 24 , 25 , 26 , 27 ]. An intensity-based optical displacement sensor measures the intensity change of the light and converts it into displacement information.…”

“…Furthermore, it uses an optical interrogation with an FPI. Other related studies have used MOEMS to measure pressure [ 16 , 20 , 28 ], strain [ 23 , 29 ], or in-plane motion [ 3 , 25 ]. However, some require a stable optical reference and no mechanical connection but still need open optical access paths to the moving target section [ 3 , 26 ].…”

Fully tunable Fabry-Pérot cavity based on MEMS Sagnac loop reflector with ultra-low static power consumption

“…Considerable efforts have been made to implement this component on silicon photonics platforms so far. The integrated Fabry-Pérot interferometer finds its applications in optical sensors [4][5][6][7][8][9] , lasers [10][11][12][13][14] , and filters [15][16][17][18] . While many on-chip Fabry-Pérot interferometers have been developed based on Bragg gratings [19][20][21][22] , they often require complex design efforts and delicate fabrication processes due to their subwavelength scale sizes.…”

Dynamic Focusing (DF) Cone-Based Omnidirectional Fingertip Pressure Sensor with High Sensitivity in a Wide Pressure Range

“…Over the past ten years, there has been extensive research on advancing diverse pressure sensor technologies and transducer techniques. The majority of these approaches can be classified into four categories: piezoresistive [5][6][7][8], electromagnetic [9][10][11][12], microelectro-mechanical [13][14][15][16], and capacitive [17][18][19][20][21][22][23][24][25][26].…”