Tunable Athermal Multi-FBG Package Using a Bending Bimetal Structure

Abstract

The Fiber Bragg Gratings (FBGs) written by ultraviolet light into the core of an optical fiber have developed into a critical component for many applications in the fiber-optic communication system. A stable temperature compensation mechanism is essential to the successful usage of FBG-based devices. In this paper, the bimetal-based temperature-compensating package with tunable mechanism was developed. Such a tunable mechanism serves as prestress and post-tuning mechanisms of fixture in order to obtain a predetermined central wavelength. With the aid of developed experimental procedure, this compact and easily manufactured package can achieve temperature coefficient of 8.3×10−4 nm/°C in the temperature range from −40°C to 80°C. The same package can also be used for multi-FBG applications.