Patent ID: 8831051

Claim:
A device for producing laser light at different optical wavelengths, comprising: an array of tunable lasers that each emit laser light that is a channel spacing wavelength away from the laser light of an adjacent tunable laser in the array, wherein each tunable laser in the array includes: a tunable sampled Bragg grating reflector for producing laser light having reflectivity peaks within a tunable spectral range, wherein the tunable sampled Bragg grating reflector is coupled to be tuned by a common control signal; a second grating reflector that is spaced from the tunable sampled Bragg grating reflector to form an optical resonator with the tunable sampled Bragg grating reflector; and a gain section between the tunable sampled Bragg grating reflector and the second grating reflector, the gain section capable of being electrically energized to amplify the laser light; and a laser control unit coupled to control the common control signal to synchronously tune the tunable sampled Bragg grating reflector of each tunable laser from a first sub-band within a first band of the tunable spectral range to a second sub-band within a second band of the tunable spectral range, wherein the first sub-band is a coarse tuning step from the second sub-band and the coarse tuning step is approximately equal to a number of the tunable lasers in the array multiplied by the channel spacing wavelength.