Sleeve-Type Ultra Miniature Optical Fiber Pressure Sensor Fabricated by DRIE

A diaphragm-type optical fiber pressure sensor, which has a sleeve for fiber insertion, is proposed, and its fundamental characteristics are demonstrated. The sleeve structure is fabricated by deep reactive ion etching (DRIE). The diaphragm with the sleeve is suitable for highly reliable and easy bonding between the sleeve and an optical fiber. The light intensity change by a Fabry-Perot interferometer according to pressure is increases by an improved DRIE method. The mesa attached to the diaphragm increased reflectance. The method of mass production for the developed diaphragm will be useful for realizing a low-cost pressure sensor.