Development of a doppler asymmetric spatial heterodyne interferometer for ground-based wind field detection at the 557.7 nm wavelength

A ground-based Doppler Asymmetric Spatial Heterodyne (DASH) interferometer with a high Sig-nal-to-Noise Ratio (SNR) and large etendue (A ohm) with thermal compensation was developed to detect wind field information in the middle atmosphere. The detailed parameters and index of the DASH interferometer were developed for the 557.7 nm oxygen airglow spectral line. The system was designed with an expanded Field Of View (FOV) and thermal compensation. The half-FOV angle reached 2.815 degrees, the etendue was 0.095 25 cm2sr, and the system's SNR was approximately 113.75. Through the thermal compensation design, the final optical path difference with temperature variation (d Delta d0/dT) was only 2.224x10-7mm/degrees C. The optic-al system was designed and optimized according to the corresponding parameters. Image-side telecentric and bilateral telecentric optical system structures were used in the entrance optics and exit optics, respectively, and parameters such as telecentricity and distortion met the detection requirements. To verify the design res-ults, a ground-based DASH interferometer experimental platform was constructed, and indoor and outdoor ground-based experiments were conducted. In the final experiment, clear interference fringes were obtained, which proves that the system design results of the DASH interferometer are reasonable, and the system 's SNR and etendue meet the detection requirements.