Polymers are widely used in many fields such as radiative cooling, infrared stealth, optical fibers and solar cells. In this work, the complex refractive indices of seven polymers such as polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polycarbonate (PC), polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polyetherimide (PEI) are measured by spectroscopic ellipsometry (SE) combined with the ray tracing method (RTM) from near-infrared to mid-infrared bands (2–20 µm). The measured results of PDMS have been proved to be accurate by comparing them with previous data in the literature. The obtained refractive indices of polymers in this paper have been compared with the results calculated by the Kramers-Kronig relations. Finally, we analyze the reasons of absorption peaks of these materials in infrared bands by the vibration of chemical bonds in molecules.

聚合物广泛用于许多领域，例如辐射冷却，红外隐身，光纤和太阳能电池。在这项工作中，七种聚合物的复折射率，例如聚二甲基硅氧烷（PDMS），聚甲基丙烯酸甲酯（PMMA），聚碳酸酯（PC），聚苯乙烯（PS），聚对苯二甲酸乙二醇酯（PET），聚氯乙烯（PVC）和聚醚酰亚胺（PEI） ）是通过椭圆偏振光谱（SE）结合射线追踪法（RTM）在近红外到中红外波段（2–20 µm）进行测量的。通过将PDMS的测量结果与文献中的先前数据进行比较，已证明它们是准确的。将本文获得的聚合物的折射率与通过Kramers-Kronig关系计算的结果进行了比较。最后，