Temperature-insensitive strain measurement using differential double Bragg grating technique

✍ Scribed by V.V. Spirin; M.G. Shlyagin; S.V. Miridonov; I. Marquez

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 121 KB
• Volume: 33
• Category: Article
• ISSN: 0030-3992
• DOI: 10.1016/s0030-3992(00)00115-8

✦ Synopsis

A novel di erential double Bragg grating sensor for temperature-insensitive strain measurement is presented. The sensor consists of two identical weak measuring and reference gratings separated by some distance. The reference grating is placed inside the silica capillary that made it almost strain insensitive. The basic idea in di erential double Bragg grating sensor is to measure the energy of the oscillating term in the re ection spectrum of double Bragg grating structure. The normalized energy of the interference term depends on the pitch di erence of the two gratings and does not change when pitch variations of both gratings are equal with temperature variation. Therefore, the normalized energy of the interference term can be used for the temperature-insensitive strain measurement.