Abstract. Visible-near infrared (VIS-NIR) spectral data are widely used for remotely estimating a number of crop health metrics. In general, these indices and models do not explicitly account for leaf surface characteristics, which themselves can be indicators of plant status or environmental responses. To explicitly include leaf surface characteristics, data are required linking optical properties to surface characteristics. We present the design and experimental validation of a goniospectropolarimeter (GoSPo) that combines the capabilities of a spectrometer, goniometer, and polarimeter. GoSPo was designed with the objective of studying the relationships between leaf surface characteristics and the resulting light reflectance, transmission, and polarization as functions of both direction and VIS-NIR spectra. Using six motors, a pneumatic system, two spectrometers, and a combination of lenses, polarizers, and mirrors, GoSPo can examine a leaf from a particular angle, approximate hemispherical transmittance and reflectance (with root-mean-square error values of 0.0189 and 0.0216 for reflectance and transmittance, respectively, compared to a spectrophotometer and integrating sphere), and obtain spectral polarization measurements without disrupting the sample between measurements. The data collected with GoSPo will aid in model development for remote sensing applications.

中文翻译：

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GoSPo：一种用于评估与叶片光学特性相关的反射率、透射率和表面偏振的测角分光偏振计

摘要。可见近红外 (VIS-NIR) 光谱数据被广泛用于远程估计许多作物健康指标。一般来说，这些指数和模型并没有明确说明叶面特征，这些特征本身可以作为植物状态或环境响应的指标。为了明确包括叶表面特征，需要将光学特性与表面特征联系起来的数据。我们介绍了结合光谱仪、测角仪和旋光仪功能的测角分光偏振计 (GoSPo) 的设计和实验验证。GoSPo 的设计目的是研究叶片表面特征与作为方向和 VIS-NIR 光谱函数的光反射、透射和偏振之间的关系。使用六个马达，一个气动系统，两个光谱仪，以及透镜、偏振器和反射镜的组合，GoSPo 可以从特定角度检查叶子，近似半球透射率和反射率（反射率和透射率的均方根误差值分别为 0.0189 和 0.0216，比较分光光度计和积分球），并在测量之间不破坏样品的情况下获得光谱偏振测量。使用 GoSPo 收集的数据将有助于遥感应用的模型开发。与分光光度计和积分球相比），并在测量之间不破坏样品的情况下获得光谱偏振测量。使用 GoSPo 收集的数据将有助于遥感应用的模型开发。与分光光度计和积分球相比），并在测量之间不破坏样品的情况下获得光谱偏振测量。使用 GoSPo 收集的数据将有助于遥感应用的模型开发。