Optical Constant Determination of Thin Polymer Films in the Infrared.
Abstract
Thin films of poly(vinyl chloride), poly(methyl methacrylate), and poly(styrene) were analysed by Fourier transform infrared spectroscopy. The interference fringes present in the transmission spectra of these samples were used to determine thickness and average refractive index (in non-absorbing regions). Subsequent Kramers-Kronig analysis of these transmission spectra provided the the dispersion of the refractive index and the absorptive index across the entire mid-infrared region. The refractive index and the absorptive index, collectively known as the optical constants, are intrinsic properties of a material, and their spectra are invariant with respect to the geometry and/or thickness of a sample. The intrinsic nature of the derived optical constants was verified by the absence of interference fringes in the optical constant spectra, and by the good agreement obtained between our optical constant spectra and those of other authors. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 24, 1984
- Accession Number
- ADA145669
Entities
People
- H. Ishida
- J. L. Koenig
- R. T. Graf
Organizations
- Case Western Reserve University