OPTICAL WAVEGUIDE STRAIN SENSORS WITH A BRAGG REFLECTOR ON A FLEXIBLE SUBSTRATE

摘要

An optical waveguide strain sensor is provided to bend a plastic substrate by directly forming a polymer optical waveguide and a Bragg grating on a flexible plastic substrate. A polymer optical waveguide is formed on a top part of a flexible substrate(110). The optical waveguide has a clade(120) and a core(130). One or more polymer Bragg grating(140) is formed on the optical waveguide. Two or more Bragg gratings are connected to a single optical waveguide. A polymer of the polymer waveguide has a negative thermo-optic coefficient. The flexible substrate has a positive coefficient of thermal expansion.