CONTINUOUSLY-TUNABLE EXTERNAL CAVITY LASER

摘要

The present invention provides a continuously-tunable external cavity laser (ECL) with a compact form factor and precise tuning. A novel interference filter which may be used to tune the ECL provides an absence of mode-hopping and reduced feedback from both spurious interference (210) and reflections (214) in the external cavity. A novel tuning mechanism is disclosed which provides for mechanical FM tuning of a wide range ECL tuning elements such as an interference filter, a diffraction element and a retroreflector (122). A novel feedback circuit is disclosed which provides closed loop feedback for selecting output wavelength in a laser.