BRAGG GRATING PRESSURE SENSOR

摘要

A fiber grating pressure sensor includes an optical sensing element (20, 600 ) which includes an optical fiber (10) having a Bragg grating (12) impressed therein which is encased within and fused to at least a portion of a glass capillary tube (20) and/or a large diameter waveguide grating (600) having a core and a wide cladding and which has an outer transverse dimension of at least 0.3 mm. Light (14) is incident on the grating (12) and light (16) is reflected from the grating (12) at a reflection wavelength .lambda.1. The sensing element (20, 600) may be used by itself as a sensor or located withi n a housing (48, 60, 90, 270, 300). When external pressure P increases, the grating (12) is compressed and the reflection wavelength .lambda.1 changes.< /SDOAB>