| 摘要 |
A long-period fiber grating filter device which includes a core having refractive index modulations formed therein at every predetermined distance, a cladding surrounding the core, a coating covering the cladding portion not adjacent to the long-period fiber gratings, a recoating covering the cladding portion adjacent to the long-period fiber gratings, a long-period fiber grating where a coupling wavelength exhibits a negative wavelength shift with respect to temperature change according to the amount of a dopant added to the core, and a recoating material where the refractive index decreases with temperature increase and the coupling wavelength exhibits a positive wavelength shift by the effect of the recoating material, wherein the negative wavelength shift in long-period fiber grating itself and the positive wavelength shift by the effect of the recoating material balance each other to eliminate temperature control in the long-period grating filter device. |
