Patent ID: 8701500

Claim:
A fiber optic strain sensor comprising: at least one optical fiber composed of at least one core and at least one cladding around the core or cores to substantially confine light to the core or cores, at least one buffer layer further surrounding the outermost cladding layer of said core or cores and bonded to said outermost cladding layer, at least one fiber optic sensing area within said optical fiber comprised of at least one of a fiber Bragg grating, Fabry-Perot or interferometric optical structure configured to sense strain, at least two low-creep anchor structures bracketing said at least one fiber optic sensing area, a provision for attaching each anchor structure of said fiber optic strain sensor to at least one independent body, the strain in which is to be measured, and a provision for attaching each anchor structure of said fiber optic strain sensor separately to two other bodies, the movement between which is to be measured.