Real-Time, Mid-Infrared Spectroscopic Imaging Microscopy Using Indium Antimonide Focal-Plane Array Detection

Abstract

A different approach toward mid-infrared spectroscopic imaging microscopy is introduced in which instrumentation is designed about an InSb multichannel, focal-plane array detector and a variable-bandpass dielectric filter. The system may be configured for either macroscopic or microscopic applications, and high-fidelity, chemically specific images may be acquired in real time. With the dielectric filter used in this assembly, continuous tuning is provided for the infrared 4000–2320 cm−1 spectral region with spectral resolutions of approximately 35–18 cm−1 at the extremes of this wavelength interval. The functioning of the imaging microscope is demonstrated with samples including polystyrene microspheres, preparations of lipids and an amino acid embedded in KBr disks, and a tissue sample derived from a coronal slice of a monkey cerebellum.