3-wavelength operation of an external cavity laser diode with cascaded fiber bragg gratings

The 3-wavelength operation of external cavity laser diode with cascaded fiber Bragg gratings is achieved. The peak wavelength of the 3-wavelength spectra are determined by the Bragg wavelength of three fiber Bragg gratings, and are 1531 nm and 1549 nm and 1554.8 nm respectively. At a bias of 52 mA, the total output power of the external cavity laser is 1 mW. The main advantages of the laser is that the wavelength of the laser is steady because of wavelength is lock at the Bragg wavelength of fiber grating, and linewidth is narrow, and cost is low. The laser can be used for interference measurement with multi-wavelength, and all-optical communication.