Divided-aperture infra-red spectral imaging system for chemical detection

A method of detecting a target species in a scene using a multi-spectral imaging system, the method comprising:

• receiving, by an aperture, infrared (IR) radiation from the scene along at least two optical channels that are spatially and spectrally different from one another;
• capturing, by an optical focal plane array (FPA) unit, a plurality of IR images corresponding to the at least two optical channels;
• processing, by a processor, the plurality of IR images to generate an output indicative of a presence of the target species in the scene;
• capturing, by a visible-light imaging sensor, a visible image of the scene corresponding to a field of view of the IR imaging system;
• determining, by the processor and based on the visible image, motion information corresponding to one or more moving objects in the scene;
• and
• suppressing, by the processor and based at least in part on the motion information, at least one false detection of the target species in the output generated from the plurality of IR images.

An infrared (IR) spectral imaging system for imaging a scene, comprising:

• an optical system configured to receive IR radiation from the scene and to form, during a single snapshot acquisition, a plurality of images of the scene that are respectively associated with different wavelength compositions, the optical system comprising a plurality of optical channels that are spatially and spectrally different from one another;
• an optical focal plane array (FPA) unit configured to receive the IR radiation via the plurality of optical channels such that the plurality of images are acquired substantially simultaneously during the single snapshot acquisition;
• and
• a processor operably coupled to the optical system and the optical FPA unit, the processor configured to aggregate the plurality of images acquired during the single snapshot acquisition into a spectral datacube having spatial coordinates and a spectral coordinate.