Fig. 1. System schematic diagram

Fig. 2. Relationship between optical path difference and interference light intensity

Fig. 3. Relationship between interference light intensity and phase difference of the output of BPF 1, BPF 2, and total laser. (a) Optical path difference of -50 μm; (b) optical path difference of 0; (c) optical path difference of 50 μm

Fig. 4. Flowchart of phase and optical path control

Fig. 5. Numerical simulation results of phase and optical path control. (a) Light intensity variation of phase control; (b) light intensity variation of optical path control; (c) total light intensity variation

Fig. 6. Spectral response of the bandpass filters. (a) (1066±1) nm; (b) (1061±1) nm; (c) (1064±5) nm

Fig. 7. Initial optical path difference between two beams

Fig. 8. Interference light intensity variation curves. (a) 1066 nm interference light intensity variation curve; (b) 1061 nm interference light intensity variation curve; (c) total light intensity variation curve

Fig. 9. Partial enlarged detail of total interference light intensity under simultaneous phase and optical path control and its spectral diagram. (a) Time domain diagram; (b) frequency domain diagram

Fig. 10. Openloop spectrogram of total interference light intensity

Fig. 11. Spectra under phase control only and simultaneous phase and optical path control

Fig. 12. Experimental results of implementing optical path control after manually changing optical path difference