Patent ID: 8820167

Claim:
A sensor comprising: a housing adapted to be secured to a component within a system to be monitored by the sensor; an optical fiber secured within said housing at a first location that is fixed relative to said housing and at a second location that is movable relative to said housing such that a sensing portion of said optical fiber between said first and second locations is able to undergo expansion and contraction resulting from movement of said optical fiber at said second location relative to said first location, said sensing portion of said optical fiber containing a fiber Bragg grating; a membrane spring assembly located in said housing, said membrane spring assembly comprising: a membrane disc having a fixed portion that is fixed relative to said housing and a central portion that is movable relative to said housing, said central portion is fixed relative to said optical fiber at said second location such that movement of said central portion causes corresponding displacement of said optical fiber at said second location to cause expansion and contraction of said sensing portion of said optical fiber containing said fiber Bragg grating; and a pointer member affixed to said optical fiber at said second location and coupled to said central portion of said membrane disc to effectively couple said optical fiber to said membrane disc; wherein the expansion and contraction of said sensing portion of said optical fiber effects a change in a light wavelength reflected by said fiber Bragg grating, wherein the light wavelength reflected by said fiber Bragg grating can be used to measure movement of said central portion of said membrane disc.