Method for determining saturated absorption lines and laser frequency stabilizing device

摘要

A method for determining saturated absorption lines includes defining (ST2A) first and second threshold values based on an output value of a light output signal. The first and second threshold values are in a magnitude relationship. An output value of a second-order differential signal of the light output signal is compared with the first and second threshold values. A determination is made as to whether the second-order differential signal following a change in a resonator length has an output waveform that displays a behavior in which the output waveform changes from less than the second threshold value to be equal to or greater than the first threshold value, and then changes to be less than the second threshold value. Based on a result of the determination by the waveform determination, a determination is made as to whether the output waveform of the second-order differential signal is the saturated absorption line (ST2C).