Abstract:
A ground-based Doppler Asymmetric Spatial Heterodyne (DASH) interferometer with high signal-to-noise ratio (SNR) and large etendue(AΩ) 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°, the etendue was 0.09525cm2sr, and the system SNR was approximately 113.75. Through the thermal compensation design, the final optical path difference with temperature variation(dΔd0/dT) was only 2.224×10-7mm/℃. The optical 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 requiremen