Near infrared hyperspectral imaging in the range 900–1700 nm was applied to classify Para rubber sheets produced from sulfuric acid coagulated latex and formic acid coagulated latex. In total, 200 Para rubber sheets were used for the development of the classification model using partial least squares discriminant analysis. Two types of sample presentation based on the reflectance and transflectance modes were compared to classify performance. The results indicated that both modes of measurement provided good classification with 98.33% accuracy. However, the transflectance mode yielded better performance than the reflectance mode as the former model had a higher correlation coefficient (0.88), lower standard error of prediction (0.176) and fewer preprocessing methods. The best transflectance mode was based on the absorbance pre-processed using the standard normal variate and the Savitzky-Golay second derivative whereas the best reflectance mode was developed using the absorbance pre-processed with a combination of Savitsky-Golay smoothing, the standard normal variate and the Savitzky-Golay second derivative. The fewer preprocessing methods in the transflectance mode suggested that less noise was present in the individual spectra compared to the spectra gathered in the reflectance mode. There was a clear difference between the color-mapped images of Para rubber sheets coagulated using sulfuric acid and formic acid, especially with the transflectance model. Each pixel in the images could be more accurately classified by the transflectance model.

应用 900-1700 nm 范围内的近红外高光谱成像对由硫酸凝固胶乳和甲酸凝固胶乳生产的 Para 橡胶片进行分类。使用偏最小二乘判别分析，总共使用了 200 个 Para 橡胶板来开发分类模型。比较基于反射率和半透射率模式的两种样品展示，以对性能进行分类。结果表明，两种测量模式都提供了良好的分类，准确率为 98.33%。然而，透反射模式比反射模式产生更好的性能，因为前者具有更高的相关系数 (0.88)、更低的预测标准误差 (0.176) 和更少的预处理方法。最佳透反射模式基于使用标准正态变量和 Savitzky-Golay 二阶导数预处理的吸光度，而最佳反射模式是使用与标准正态变量 Savitsky-Golay 平滑组合预处理的吸光度开发的和 Savitzky-Golay 二阶导数。与在反射模式中收集的光谱相比，透反射模式中较少的预处理方法表明单个光谱中存在的噪声较少。使用硫酸和甲酸凝固的 Para 橡胶片的颜色映射图像之间存在明显差异，尤其是使用半反射模型。图像中的每个像素可以通过半反射模型更准确地分类。