Infrared images are captured by sensors sensitive to light outside the visible spectrum.  A sensor’s silicon pixels are sensitive to wavelengths in the visible spectrum (~400-700 nm wavelengths) and into the lower IR wavelengths. An RGB sensor “sees” in color using a Color Filter Array (or CFA) of Red, Green & Blue (RGB)  filters arranged in a pattern (Bayer pattern).  This allows RGB “records” of the image to be captured, and a color image can be reconstructed.  ​

The RGB filters of a CFA all pass IR, so an “IR cut” filter is inserted in the optical path for color accuracy.  To capture both IR and visible information from the same sensor/camera module, the IR cut filter needs to be removed. ​

RGBIR – Special CFA patterns have incorporated IR filters into the array, interspersed between the RGB filters.  These RGBIR sensors eliminate the need for physically moving IR cut or IR notch filter elements into the optical path.  With no moving parts, these cameras are more reliable.   ​

Typical applications for IR and RGBIR cameras are Surveillance (night vision), Automotive interior monitoring, biometric recognition, and applications where a single RGBIR sensor operates both in lit conditions in RGB, and dark conditions in IR mode with invisible IR illumination. ​

Advantages of RGBIR: One sensor captures both spectra, saving cost & space (no additional camera or mechanical moving filter needed)​

Disadvantages of RGBIR: cost, image quality (less resolution due to sampling of RGB and IR channels combined into single CFA pattern, IR contamination of color channels in high IR lighting conditions (sunlight, incandescent) causing strange colors.