若干高光谱成像新技术及其应用研究

高光谱成像数据已广泛应用于地质、海洋、农林、水文、城市、环境和军事等领域,对经济的可持续发展发挥了促进作用。随着研究的深入和应用的拓展,对高光谱成像系统的技术要求呈现多样化趋势。本文简要回顾了国内外高光谱成像技术的主要发展历程,依次阐述了运动补偿高光谱成像、紧凑型热红外高光谱低温光学、宽谱段一体化机载高光谱集成、基于AOTF分光的凝视型高光谱成像以及阶跃集成滤光片等具有代表性的高光谱成像关键技术,并简要介绍了这些新技术在天宫一号、嫦娥三号等国家重大任务中的应用情况。

Key technologies of advanced hyperspectral imaging system

Since the invention of the hyperspectral imager AVIRIS (Airborne Visible and Infrared imaging spectometer) in the United States in the 1980s, hyperspectral imaging technology has seen rapid development for nearly 40 years. At present, hyperspectral imaging data are widely used in geology, marine science, agriculture, forestry, hydrology, urban studies, environmental science, and military fields; this wide use has played a catalytic role in sustainable economic development. The most typical representatives of hyperspectral imaging systems are the Tacsat-3 satellite ATERMIS, the Terra satellite, and the Aqua satellite MODIS. According to different imaging methods, hyperspectral imaging systems can be divided into three categories, namely, opto-mechanical scanning, push broom-type scanning, and staring. The hyper-spectral imager for opto-mechanical scanning features a large field of view and real-time calibration. The hyperspectral imager for push broom-type scanning exhibits a relatively high sensitivity; hence, a majority of spaceborne hyperspectral imagers are of this type. The hyperspectral imager for staring can obtain extremely high sensitivity and spectral resolution. Hyperspectral imaging systems can also be divided into prismatic spectrograph, grating spectrograph, and optical filter spectrograph depending on the difference obtained with the beam-split method. In recent years, hyperspectral imaging technology has seen rapid development in China. Representative instruments include the following:the successful development of an airborne OMIS system in 2000, the moderate resolution imaging spectrograph of ShenZhou 3 in 2003, and the infrared imaging spectrograph of Chang''E-3, which landed on the moon in 2013. The Fourier interference hyperspectral imager of environmental satellite 1 is China''s first interference hyperspectral imager, which launched into orbit in 2008. The TianGong 1 hyperspectral imager is China''s first high-resolution hyperspectral imager, which launched into space in 2011. Considering the depth of research and expansion of its application, hyperspectral imaging technology has undergone diversified development. Thus, we need to adopt new technologies to meet different application needs. This paper introduces essential technologies of the hyperspectral imaging system and their applications, including the following:(1) motion compensation spaceborne hyperspectral imaging technology of TianGong 1 based on prism spectrograph, (2) splitting technology in low temperature of compact thermal infrared hyperspectral imager, (3) integration of airborne ultraviolet/visible light/short-wave infrared/thermal infrared hyperspectral imaging technology, (4) splitting technology of a step integrated filter, and (5) staring hyperspectral imaging technology based on AOTF. Given the traction of major national mission requirements, China''s aerospace hyperspectral imaging technology has achieved important progress. The breakthrough of key technologies guarantees the enhancement of the ability to obtain spectral information. The technologies identified in this paper are representative breakthroughs in the hyperspectral imaging domain. The improvement of the core component parts will result in a high spectral resolution, high spatial resolution, and great scope of the hyperspectral imaging system.