Impact of incident angle on Fourier transform infrared spectroscopy with microstructured single-reflection elements

Fourier transform infrared spectra provide information about the composition and conformation of a sample. Microstructured single-reflection elements (mSRE) offer the ability to measure spectra of analytes while avoiding expensive ATR crystals. We demonstrate that the effective penetration depth can be adjusted by varying the incident angle. This technique allows for the continuous tuning of effective pathlength, which is particularly useful for optimising measurements to the strength of the sample absorption.