Robinson Iain, Butcher Helen L, Macleod Neil A, Weidmann Damien
Opt Express. 2021 Jan 18;29(2):2299-2308. doi: 10.1364/OE.415371.
A miniature thermal infrared laser heterodyne spectro-radiometer based on hybrid optical integration is demonstrated. A quantum cascade laser emitting at 953 cm (10.5 μm) is used as the local oscillator. Integration is achieved using hollow waveguides inscribed in a copper substrate, with slot-encapsulated optical components positioned to maintain fundamental hybrid mode coupling. The demonstrator performances are studied in the laboratory and show a noise level within 1.6 times of the ideal case. Atmospheric high-resolution transmittance spectroscopy of carbon dioxide and water vapor in solar occultation is demonstrated. The total column concentrations are derived as well as measurement uncertainties, 399.5 ± 2.2 ppm for CO and 1066 ± 62 ppm for HO. The miniature laser heterodyne spectro-radiometer demonstration opens the prospect for nanosatellite-based high spectral resolution thermal infrared atmospheric sounding.
展示了一种基于混合光学集成的微型热红外激光外差光谱辐射计。使用发射波长为953 cm（10.5μm）的量子级联激光器作为本地振荡器。通过刻蚀在铜基板中的空心波导实现集成，将带槽封装的光学元件定位以保持基本的混合模式耦合。在实验室中研究了该演示器的性能，结果表明其噪声水平在理想情况的1.6倍以内。展示了太阳掩星中二氧化碳和水蒸气的大气高分辨率透过率光谱。推导了总柱浓度以及测量不确定度，二氧化碳为399.5 ± 2.2 ppm，水汽为1066 ± 62 ppm。微型激光外差光谱辐射计的演示为基于纳米卫星的高光谱分辨率热红外大气探测开辟了前景。
