Divided-aperture infra-red spectral imaging system
Various embodiments disclosed herein describe a divided-aperture infrared spectral imaging (DAISI) system that is adapted to acquire multiple IR images of a scene with a single-shot (also referred to as a snapshot). The plurality of acquired images having different wavelength compositions that are obtained generally simultaneously. The system includes at least two optical channels that are spatially and spectrally different from one another. Each of the at least two optical channels are configured to transfer IR radiation incident on the optical system towards an optical FPA unit comprising at least two detector arrays disposed in the focal plane of two corresponding focusing lenses. The system further comprises at least one temperature reference source or surface that is used to dynamically calibrate the two detector arrays and compensate for a temperature difference between the two detector arrays.
1. An infrared (IR) imaging system configured to image a scene, the imaging system comprising:
a plurality of spatially and spectrally different optical channels comprising a plurality of cameras configured to image the scene;
at least one thermal reference source having a known temperature placed in front of the plurality of cameras and configured to be imaged by the plurality of cameras; and
a data-processing unit comprising a processor,
wherein the imaging system is configured to:
acquire with the plurality of cameras a plurality of frames having regions that include images of the reference source; and
apply a dynamic calibration correction to the plurality of cameras to allow at least one camera in the plurality of cameras to be calibrated to agree with another camera in the plurality imaging the reference source.
2. The system of claim 1 , wherein the system includes at least four optical channels.
3. The system of claim 1 , wherein the system includes at least eight optical channels.
4. The system of claim 1 , wherein a first optical channel comprises a first FPA and a second optical channel comprises a second FPA.
5. The system of claim 1 , wherein the data-processing unit is configured to detect a target species in said scene based on the data from the plurality spatially and spectrally different optical channels.
6. An infrared (IR) imaging system, the imaging system comprising:
a plurality of spatially and spectrally different optical channels comprising a plurality of cameras configured to image the scene;
a first thermal reference at a first temperature;
a second thermal reference at a second temperature different from the first temperature, wherein the radiation emitted from the first and second thermal references directed to the plurality of cameras simultaneously with radiation emitted from a scene viewed by the imaging system;
a data-processing unit configured to:
dynamically calibrate the plurality of cameras to reduce a difference in the measurements obtained using light from the first and second thermal references received by the plurality of cameras.
7. The system of claim 6 , wherein the system includes at least four optical channels.
8. The system of claim 6 , wherein the system includes at least eight optical channels.
9. The system of claim 6 , wherein a first optical channel comprises a first FPA and a second optical channel comprises a second FPA.
10. The system of claim 6 , wherein the data-processing unit is configured to detect a target species in said scene based on data from the plurality spatially and spectrally different optical channels.