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arXiv · 2305.06551

Complex refractive index measurements of Poly(methyl methacrylate) (PMMA) over the UV-VIS-NIR region

Pham Thi Hong·Hung Q. Nguyen·H. T. M. Nghiem
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Abstract

Poly(methyl methacrylate), PMMA, is a popular polymer for optical applications due to its superior transmission and reflection. However, its optical properties in the ultraviolet regime still need to be thoroughly studied. Using the reflection-transmission method, we determine its complex refractive index by numerically analyzing the measured data from thin films. The PMMA standalone film is fabricated by peeling off its substrate after spin-coating. Its transmittance and reflectance are then measured in a spectrophotometer using an integrated sphere. The complex refractive index $n+ik$ is extracted theoretically from the measured transmittance $T$ and reflectance $R$. The uncertainties of measured $n$ and $k$ are discussed in the two limits of strong absorption and weak absorption of the materials to illustrate the advantage and disadvantages of the approach.

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Pham Thi Hong, Hung Q. Nguyen, H. T. M. Nghiem. 2023-05-11. Complex refractive index measurements of Poly(methyl methacrylate) (PMMA) over the UV-VIS-NIR region. https://doi.org/10.1364/optcon.495634

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