A power-enhanced frequency-stabilized semi-external-cavity HeNe laser for short-exposure interferometry

The high-power and frequency-stabilized laser is urgently required in short-exposure interferometry.In this paper, a light source based on the semi-external-cavity HeNe laser is proposed for application.By optimizing the parameters of the resonant cavity, a high-finesse valley corresponding to monomode operation is generated on the temperature-tuned power curve of the laser.A frequency stabilization device by locating the power valley is constructed, achieving the frequency-stabilized output of about 2.5 mW.The monomode-power conversion efficiency, which is the ratio of the frequency-stabilized output and the resonator output, can reach up to 97.6%, due to the avoidance of the polarized mode selection in the internal-cavity resonator.Compared with the commercial frequency-stabilized HeNe laser, the proposed laser can improve the interferogram contrast from 0.26 to 0.70 in the vibration environment by shortening the camera exposure time.The proposed laser exhibits the high conversion efficiency of monomode power, which is very suitable for short-exposure interferometry.