Method and device for wavelength locking

摘要

A method and device for wavelength locking is provided, wherein an element having a wavelength dependent characteristic such as a Fabry Perot etalon is used to provide an output signal having an intensity that varies with wavelength. The intensity of a reference signal derived from an input signal is compared with an output from the Fabry Perot etalon to provide a feedback signal that corresponds to the frequency of the input signal. The system is calibrated before wavelength locking is performed to determine a ratio of intensities that determines a locked state or condition.