Thermochromic (TC) film possesses dynamic optical behaviors in response to change in environmental temperature, i.e., high solar reflectance during hot season and high solar absorptance during cold season. It has been proposed as an effective strategy to minimize energy use in buildings and improve indoor and outdoor thermal comfort. This study aims to computationally optimizing temperature-dependent optical properties of TC film in terms of particle size, shape, and volume concentration of TC pigment as well as film substrate. The computational system consists of electromagnetic simulation and Kubelka-Munk model. It has demonstrated that as particle size increases from 100 nm to 1000 nm, the total diffuse reflectance of TC film decreases from 10 % to 2 % below the transition temperature of TC pigment while decreases from 11 % to 2 % above the transition temperature. When changing particle shape from sphere to rod, the total diffuse reflectance of TC film is increased to 27 % below the transition temperature and 31 % above the transition temperature. Furthermore, with the substrate of aluminum, the total diffuse reflectance of TC film reaches up to 92 %. Finally, as the TC pigment concentration increases from 5%–50%, the total reflectance of TC film increases from 5 % to 34 %. This methodology provides guideline to tailor optical behaviors of optical film for better performance.

热致变色（TC）膜具有动态光学行为，可响应环境温度的变化，即在炎热季节具有高的太阳反射率，而在寒冷季节具有高的太阳吸收率。已经提出将其作为最小化建筑物中的能量消耗并改善室内和室外热舒适性的有效策略。这项研究旨在通过计算优化TC薄膜的温度相关光学特性，包括TC颜料以及薄膜基材的粒​​径，形状和体积浓度。该计算系统由电磁仿真和Kubelka-Munk模型组成。已经证明，随着粒径从100 nm增加到1000 nm，TC薄膜的总漫反射率在TC颜料的转变温度以下从10％降低到2％，而在转变温度以上从11％降低到2％。当将颗粒形状从球形更改为棒形时，TC膜的总漫反射率将增加到转变温度以下27％和转变温度以上31％。此外，在铝基板上，TC膜的总漫反射率高达92％。最后，随着TC颜料浓度从5％–50％增加，TC膜的总反射率从5％增加到34％。该方法学为调整光学膜的光学性能提供了指导，以获得更好的性能。TC膜的总漫反射率在转变温度以下增加到27％，在转变温度以上增加到31％。此外，在铝基板上，TC膜的总漫反射率高达92％。最后，随着TC颜料浓度从5％–50％增加，TC膜的总反射率从5％增加到34％。该方法学为调整光学膜的光学性能提供了指导，以获得更好的性能。TC膜的总漫反射率在转变温度以下增加到27％，在转变温度以上增加到31％。此外，在铝基板上，TC膜的总漫反射率高达92％。最后，随着TC颜料浓度从5％–50％增加，TC膜的总反射率从5％增加到34％。该方法学为调整光学膜的光学性能提供了指导，以获得更好的性能。