Patent ID: 8509271

Claim:
A method for manufacturing an optical fiber grating that includes first and second gratings that configure an optical resonator, the method comprising: forming the first grating by radiating ultraviolet light to an optical fiber so that a irradiation intensity Z satisfies the following Equation 1: Z ≦(Δλ S/x+ 0.04556 Y 2+1.2225 Y )/(0.05625 Y 2+1.6125 Y ) Equation 1, where, Z represents an irradiation intensity (mJ/mm2) of the ultraviolet light, ΔλS represents the maximum shift amount of a reflection center wavelength of the first grating that is allowed as long as reflection wavelengths of the first grating and second grating overlap each other, x represents a shift amount of the reflection center wavelength per temperature change of 1° C. (nm/° C.) in the first grating, and Y represents an intensity (W) of the wave-guided light; wherein x is a real number greater than zero and Y is a real number greater than zero.