Xie Yunqiang, Liu Chunyu, Liu Shuai, Fan Xinghao
Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Sensors (Basel). 2021 Jun 24;21(13):4313. doi: 10.3390/s21134313.
Nighttime light remote sensing has unique advantages on reflecting human activities, and thus has been used in many fields including estimating population and GDP, analyzing light pollution and monitoring disasters and conflict. However, the existing nighttime light remote sensors have many limitations because they are subject to one or more shortcomings such as coarse spatial resolution, restricted swath width and lack of multi-spectral data. Therefore, we propose an optical system of imaging spectrometer based on linear variable filter. The imaging principle, optical specifications, optical design, imaging performance analysis and tolerance analysis are illustrated. The optical system with a focal length of 100 mm, F-number 4 and 43° field of view in the spectrum range of 400-1000 nm is presented, and excellent image quality is achieved. The system can obtain the multi-spectral images of eight bands with a spatial resolution of 21.5 m and a swath width of 320 km at the altitude of 500 km. Compared with the existing nighttime light remote sensors, our system possesses the advantages of high spatial and high spectral resolution, wide spectrum band and wide swath width simultaneously, greatly making up for the shortage of the present systems. The result of tolerance analysis shows our system satisfy the requirements of fabrication and alignment.
夜间灯光遥感在反映人类活动方面具有独特优势，因此已被应用于许多领域，包括估算人口和国内生产总值、分析光污染以及监测灾害和冲突。然而，现有的夜间灯光遥感器存在许多局限性，因为它们存在一个或多个缺点，如空间分辨率粗糙、扫描宽度受限以及缺乏多光谱数据。因此，我们提出了一种基于线性可变滤光片的成像光谱仪光学系统。阐述了其成像原理、光学规格、光学设计、成像性能分析和公差分析。给出了一种焦距为100mm、F数为4且在400 - 1000nm光谱范围内视场为43°的光学系统，该系统实现了优异的图像质量。该系统在500km高度可获得空间分辨率为21.5m、扫描宽度为320km的8波段多光谱图像。与现有的夜间灯光遥感器相比，我们的系统同时具备高空间分辨率、高光谱分辨率、宽光谱带和宽扫描宽度的优势，极大地弥补了现有系统的不足。公差分析结果表明我们的系统满足制造和对准要求。
