Korb A R, Dybwad P, Wadsworth W, Salisbury J W
Appl Opt. 1996 Apr 1;35(10):1679-92. doi: 10.1364/AO.35.001679.
A hand-held, battery-powered Fourier transform infrared spectroradiometer weighing 12.5 kg has been developed for the field measurement of spectral radiance from the Earth's surface and atmosphere in the 3-5-µm and 8-14-µm atmospheric windows, with a 6-cm(-1) spectral resolution. Other versions of this instrument measure spectral radiance between 0.4 and 20 µm, using different optical materials and detectors, with maximum spectral resolutions of 1 cm(-1). The instrument tested here has a measured noise-equivalent delta T of 0.01 °C, and it measures surface emissivities, in the field, with an accuracy of 0.02 or better in the 8-14-µm window (depending on atmospheric conditions), and within 0.04 in accessible regions of the 3-5-µm window. The unique, patented design of the interferometer has permitted operation in weather ranging from 0 to 45 °C and 0 to 100% relative humidity, and in vibration-intensive environments such as moving helicopters. The instrument has made field measurements of radiance and emissivity for 3 yr without loss of optical alignment. We describe the design of the instrument and discuss methods used to calibrate spectral radiance and calculate spectral emissivity from radiance measurements. Examples of emissivity spectra are shown for both the 3-5-µm and 8-14-µm atmospheric windows.
已研发出一款重量为12.5千克的手持式、电池供电的傅里叶变换红外光谱辐射计，用于在3 - 5微米和8 - 14微米大气窗口对地球表面和大气的光谱辐射进行现场测量，光谱分辨率为6厘米⁻¹。该仪器的其他版本使用不同的光学材料和探测器，测量0.4至20微米之间的光谱辐射，最大光谱分辨率为1厘米⁻¹。此处测试的仪器测得的噪声等效温差为0.01°C，在现场测量表面发射率时，在8 - 14微米窗口的精度为0.02或更高（取决于大气条件），在3 - 5微米窗口的可测量区域内精度在0.04以内。干涉仪独特的专利设计使其能够在0至45°C、相对湿度0至100%的天气条件下以及如直升机飞行等振动强烈的环境中运行。该仪器已进行了3年的辐射和发射率现场测量，光学对准未出现损失。我们描述了该仪器的设计，并讨论了用于校准光谱辐射以及根据辐射测量计算光谱发射率的方法。展示了3 - 5微米和8 - 14微米大气窗口发射率光谱的示例。
