Brussels Photonics (B-PHOT), Applied Physics and Photonics Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
Royal Meteorological Institute of Belgium, Avenue Circulaire 3, 1180 Brussels, Belgium.
Sensors (Basel). 2021 Jun 29;21(13):4444. doi: 10.3390/s21134444.
The measurement of the Earth's Outgoing Longwave Radiation plays a key role in climate change monitoring. This measurement requires a compact wide-field-of-view camera, covering the 8-14 µm wavelength range, which is not commercially available. Therefore, we present a novel thermal wide-field-of-view camera optimized for space applications, featuring a field of view of 140° to image the Earth from limb to limb, while enabling a high spatial resolution of 4.455 km at nadir. Our cost-effective design comprises three germanium lenses, of which only one has a single aspherical surface. It delivers a very good image quality, as shown by the nearly-diffraction-limited performance. Radiative transfer simulations indicate excellent performance of our camera design, enabling an estimate of the broadband Outgoing Longwave Radiation with a random relative error of 4.8%.
地球长波辐射通量的测量在气候变化监测中起着关键作用。这种测量需要一个紧凑的宽视场相机，覆盖 8-14μm 的波长范围，但目前市面上没有这种相机。因此，我们提出了一种新型的热宽视场相机，专为空间应用而优化，视场为 140°，可从边缘到边缘成像地球，同时在天底处实现 4.455km 的高空间分辨率。我们的经济高效的设计包括三个锗透镜，其中只有一个具有单个非球面。它提供了非常好的图像质量，如近乎衍射极限的性能所示。辐射传输模拟表明我们的相机设计具有出色的性能，能够以 4.8%的随机相对误差估算宽带长波辐射通量。
