Fiber Bragg Gratings Take Control

Anish Goyal and Martin Muendel, Polaroid Corp.

The ability to write Bragg gratings in optical fiber by simple exposure to UV light is the key to producing a variety of devices. The writing technique is inexpensive, simple, and allows a flexibility in the design of wavelength selective components.
One application for these gratings is wavelength stabilization of lasers, which means control of a laser's wavelength and possibly enforcement of single-axial-mode lasing. Fiber Bragg gratings are attractive devices for this application because they are easy to make and offer precise control of the center wavelength, excellent temperature stability and tunability. These benefits can significantly improve the performance and capabilities of diode lasers and fiber lasers.
Fiber Bragg gratings' benefits make them attractive to other applications as well. In telecommunications systems, they are used for dispersion compensation in fiber optic transmission systems, demultiplexing filters for wavelength division multiplexing systems, and long-period gratings for gain flattening of erbium-doped fiber amplifiers. They are also stimulating growth in fiber optic applications outside of telecommunications, such as nonlinear frequency conversion, spectroscopy, and remote sensing.