Miniature all-glass robust pressure sensor.

This paper describes a newly designed all-glass miniature (Ø 125 microm) fiber-optic pressure sensor design that is appropriate for high-volume manufacturing. The fabrication process is based on the chemical etching of specially-designed silica optical fiber, and involves a low number of critical production operations. The presented sensor design can be used with either single-mode or multi-mode lead-in fiber and is compatible with various types of available signal processing techniques. A practical sensor sensitivity exceeding 1000 nm/bar was achieved experimentally, which makes this sensor suitable for low-pressure measurements. The sensor showed high mechanical stability, good quality of optical surfaces, and very high tolerance to pressure overload.