METHOD TO TUNE EMISSION WAVELENGTH OF SEMICONDUCTOR LASER DIODE

摘要

A method to tune an emission wavelength of a laser diode (LD) finely is disclosed. The method first controls a temperature of the etalon filter in T1 or T2, where the transmittance of the etalon filter becomes 40 to 50%, assuming a height between the peak and the bottom of the periodic transmittance to be 100%, at the grid wavelength λ1 or λ2, respectively. Then, the temperature of the LD is adjusted such that the intensity of light emitted from the LD and transmitted through the etalon filter becomes 40 to 50%.