K. Yoshida and S. Komatsu: Wavelength Shift Measurement Using a Dual-Photodiode for the Reflected Light from a Strained Fiber Bragg Grating , Technical Report (Advanced Research Institute for Science and Engineering, Waseda Univ.), No.2001-9 (2001), 1-9.

Wavelength sensing technique using dual photodiodes is applied to the wavelength measurements of the light reflected from a fiber Bragg grating (FBG). This technique provides very simple means which is capable of determining the central wavelength of the reflected light even if the light power changes rather greatly. The feasibility and attainable precision of the wavelength sensing technique is first examined experimentally. Then its application scheme to a FBG strain sensor is presented along with some experimental results.