Novel route to faster Fourier transform infrared spectroscopic imaging

Fourier transform infrared (FT-IR) spectroscopic imaging microscopy couples a focal plane array (FPA) detector, integrated within an infrared microsco pe assembly, to an interferometer for attaining a multiplex/multichannel si gnal detection advantage. While this configuration should enable the acquis ition of spatially resolved spectra over the entire field of view of a samp le in the time that it takes a conventional FT-IR spectrometer to record a single spectrum, data acquisition in an imaging modality is an intrinsicall y slower process. We present a novel collection technique for step-scan, mi cro-imaging spectrometers that both allows large numbers of samples to be i maged rapidly and provides higher signal-to-noise ratios (SNRs) for given e xperimental time intervals. For example, data may be collected in as little as one minute, while SNRs greater than 800 are achieved for data acquired in less than 10 min. Imaging data acquired in the proposed, more rapid appr oach exhibit no loss in fidelity compared to data recorded by the conventio nal imaging techniques.