Comb laser

A method for generating radiation, the method comprising:

• positioning a first reflector and a second reflector to define an optical path;
• placing a gain medium configured to amplify laser radiation within a given gain band on the optical path between the first and second reflectors;
• disposing on the optical path between the first and second reflectors a comb filter configured to pass a set of distinct wavelength sub-bands within the gain band, the set of distinct wavelength sub-bands defining a comb;
• disposing on the optical path between the first and second reflectors, in series with the comb filter, a bandpass filter having a passband encompassing a subset of the wavelength sub-bands in the comb;
• and
• applying an electrical drive to the gain medium, whereby the laser radiation in the subset of the wavelength sub-bands in the comb is emitted through the second reflector.