Abstract:Laser frequency stabilization method based on frequency modulation spectroscopy has been applied in space spectrum instrument as this method is simple and the frequency stability is very high. The amplitude of the absorption signal is used as the feedback signal. And the amplitude of the signal is usually acquired by a reference signal with the same frequency and phase. As the phase between the absorption signal and the reference signal is unknown, phase shifter is used in this method. In order to remove the phase shifter, it uses the mixed signal of absorption and dispersion as the feedback signal. The amplitude and the phase of the mixed signal can tell us the real wavelength of the laser. Two orthogonal reference signals are used to acquire the mixed signal, so the phase shifter is removed in this method. At last a method which is used to judge the position of the wavelength is also put forward.
