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Publication Citation: Angle-Dependent Absolute Infrared Reflectance and Transmittance Measurements

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Author(s): Simon G. Kaplan; Leonard M. Hanssen;
Title: Angle-Dependent Absolute Infrared Reflectance and Transmittance Measurements
Published: October 01, 2000
Abstract: A goniometric system is used in conjuction with an FT-IR (Fourier-Transform Infrared) spectrophotometer to perform reflectance and transmittance measurements as a function of angle of incidence from 12 to 80 . The input beam is polarized using a high-quality Ge reflective Brewster-angle polarizer, and is focussed onto the sample with an approximately f/50 geometry. The average angle of incidence is controlled to within 0.05 , and spectra are recorded for both s- and p-polarization over a wavelength range of 1.6 mm to 5.2 mm, using a photoconductive InSb detector. Measurements results are compared to the predictions of the Fresnel equations in order to assess the accuracy of the instrument.
Conference: Proceedings of SPIE--the International Society for Optical Engineering
Proceedings: Optical Diagnostic Methods for Inorganic Materials , Conference | 2nd | Optical Diagnostic Methods for Inorganic Materials II | SPIE
Volume: 4103
Dates: August 3-4, 2000
Keywords: index of refraction;infrared;polarization;reflectance;transmittance
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