IEC 62788-1-4:2016提供了一种测量光伏（PV）组件中所用封装材料光学透射率的方法。本程序中的标准化测量量化了封装对光伏电池的预期透射率。随后的太阳加权透射率计算允许在不同材料之间进行比较。未干燥材料的结果可用于封装制造商的数据表、制造商的材料或工艺开发、制造质量控制（材料验收），或用于模块性能分析。 该测量方法还可用于监测封装材料在风化后的性能，以帮助评估其耐久性。

IEC 62788-1-4:2016 provides a method for measurement of the optical transmittance of encapsulation materials used in photovoltaic (PV) modules. The standardized measurements in this procedure quantify the expected transmittance of the encapsulation to the PV cell. Subsequent calculation of solar-weighted transmittance allows for comparison between different materials. The results for unweathered material may be used in an encapsulation manufacturer's datasheets, in manufacturer's material or process development, in manufacturing quality control (material acceptance), or applied in the analysis of module performance. This measurement method can also be used to monitor the performance of encapsulation materials after weathering, to help assess their durability.