Abstract: The present invention is a fused/taper fiber optic coupler and related methodologies for a fuse/taper fiber optic coupler with an FBG that does not excite cladding modes and maintains the coupling regions of the fibers in the proper relationship to one another without a complex and expensive process. Aspects of the fused/taper fiber optic coupler include the use of optical fibers with a three layer structure. The optical fibers include a photosensitive core layer, a photosensitive inner cladding layer, and a photo-insensitive outer cladding layer. Coupling regions are formed in each optical fiber by removing the outer cladding layer and the coupling regions in each optical fiber are then helically intertwined. The intertwined coupling regions are then heated and drawn forming a tapered area in which an FBG may be written.

Abstract: A passive temperature compensating package for a fiber Bragg grating device in which the fiber Bragg grating is written to the fiber prior to the temperature compensation being set. As the temperature of the package increases the fiber is de-stressed and at the desired proper resonant frequency, the fiber containing the fiber Bragg grating is secured to the package. As the package cools and expands, the fiber is pre-stressed and maintains the desired resonant frequency.