Patent ID: 6907164

Claim:
An adjustable athermally packaged optical fiber device, comprising: an elongated hollow structure having a longitudinal axis and first and second extremities; a free and a threaded member respectively projecting inwardly of said hollow structure from the first and second extremities thereof, the free and threaded members each having a fiber-receiving bore therein extending along the longitudinal axis, the free member being rotatable around said longitudinal axis with respect to the hollow structure, and the threaded member being threadedly engaged with the hollow structure along the longitudinal axis; an optical fiber mounted under tension in said hollow structure through the fiber-receiving bores of the free and threaded members, a first point of said fiber being affixed to the free member, a second point thereof being affixed to the threaded member at an end thereof extending outside of the hollow structure, said optical fiber having a refractive index grating extending between said first and second points and having a characteristic spectral response, the hollow structure, free member and threaded member each having a coefficient of thermal expansion selected so that they together compensate for a temperature dependency of said characteristic spectral response of the grating; rotating means for jointly rotating said free and threaded members with respect to the hollow structure to adjust a wavelength position of the characteristic spectral response of the grating; and a locking nut threadedly engaged with said threaded member at a position completely outside of the hollow member and abutting on the second extremity of said hollow member so as to exert a longitudinal pressure thereon for finely adjusting said wavelength position.