Wide tuning range fiber bragg grating filter

摘要

An optical filter having a wide tuning range and a method of making the same. A fiber Bragg grating member (408) having a selected grating pitch is coupled to a plurality of actuating members such as Shape Memory Alloys (406A-406F). A current source or thermal source is included for providing a controlled amount of current or heat so as to cause a change in the length of the actuating members. The length of the fiber Bragg grating member is accordingly changed also. The grating pitch is correspondingly altered, thereby causing a change in the Bragg resonance wavelength of the grating. In response, a reflected optical signal selected from incoming multiplexed optical signals tunes to a different wavelength. A closed-loop controller is provided for controlling energy inputs to the actuating members to modulate the tuning of the reflected optical signals.