Continuously tunable, precise, single frequency optical signal generator

To realize a genuine CW optical frequency synthesizer, a continuously tunable single-frequency CW laser has been employed to track precisely any arbitrary component of a wide bandwidth phase-stabilized optical comb. We demonstrate experimentally two fundamental aspects of optical frequency synthesis, namely, precise setting of the laser frequency at an arbitrary pre-determined value, and continuous tuning of the laser frequency with the digital precision known in radio frequency synthesis. A typical computer-automated search-and-lock procedure finishes on one-minute time scale. (C) 2002 Optical Society of America.