We propose and demonstrate an infrared (IR) absorption spectrometer, made with a spatially variable photonic bandgap (PBG) structure, a blackbody source, and a simple IR detector, to identify the IR molecular fingerprints of analyte molecules. The PBG-based structure consists of thermally evaporated, IR transparent, high-refractive-index chalcogenide quarter-wave stacks (QWS) with a cavity laye...

The Smithsonian far-infrared spectrometer is a remote sensing Fourier transform spectrometer that measures the midand far-infrared thermal emission spectrum of the stratosphere from balloon and aircraft platforms. The spectrometer has had nine successful balloon flights from 1987 to 1994, flying at float altitudes of 36–39 km and collecting 131 hours of midlatitude stratospheric limb spectra. T...