Random-access digitally-tuned optical frequency synthesizer

Abstract From the Canadian patent

Abstract, A digitally tuned optical frequency synthesizer includes a laser control arrangement for tuning the laser over a range of frequencies. The laser is tunable in response to different magnitudes of injected bias current. A digital processor determines bias current values which produce the desired different operating frequencies corresponding to a set of Fabry-Perot resonant frequencies. Those current values are stored in the digital processor for ready retrieval. During operation one of the bias current, values is retrieved and is applied to the laser. If the laser characteristic curve has drifted, an incremental bias current is determined and is added to the retrieved bias current …