An athermally packaged optical fiber device, such as a Bragg grating, is provided.
The device includes a hollow structure, and a free and a threaded member projecting
in the hollow structure from both ends. The optical fiber is mounted in tension
inside the hollow structure through longitudinal fiber-receiving bores in both
members, and has an anchor point affixed to each member with the grating therebetween.
The anchor point of the threaded member is provided outside of the hollow structure,
making the device more compact. The free and threaded members are rotatable together
to adjust the resonant wavelength of the grating, and a nut may be provided to
allow a fine-tuning. The hollow structure, free member and threaded member have
a coefficient of thermal expansion selected so that they together compensate for
the temperature dependency of the Bragg wavelength.
