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Title: Correcting thermal-emission-induced detector saturation in infrared spectroscopy

We found that temperature-dependent infrared spectroscopy measurements (i.e., reflectance or transmittance) using a Fourier-transform spectrometer can have substantial errors, especially for elevated sample temperatures and collection using an objective lens. These errors can arise as a result of partial detector saturation due to thermal emission from the measured sample reaching the detector, resulting in nonphysical apparent reduction of reflectance or transmittance with increasing sample temperature. Here, we demonstrate that these temperature-dependent errors can be corrected by implementing several levels of optical attenuation that enable convergence testing of the measured reflectance or transmittance as the thermal-emission signal is reduced, or by applying correction factors that can be inferred by looking at the spectral regions where the sample is not expected to have a substantial temperature dependence.

 
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Award ID(s):
1750341
NSF-PAR ID:
10372901
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Express
Volume:
30
Issue:
21
ISSN:
1094-4087; OPEXFF
Page Range / eLocation ID:
Article No. 38458
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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