Optimized Two-Wavelength Focal-Plane Arrays of QWIPs

A concept for optimizing the designs of two-wavelength GaAs-based quantum-well infrared photodetectors (QWIPs) could make it practical to use focal-plane arrays of QWIPs as image sensors in two-wavelength infrared cameras. Potential applications for such cameras include surveillance, tracking of military targets, night vision, and thermal mapping. One important advantage of a two-wavelength over a one-wavelength camera is the possibility of using Planck's radiation law to calculate the temperature of an imaged object from the ratio between the brightnesses of the object at the two wavelengths.