Clutter discriminating focal plane arrays

摘要

A quantum well infrared photodetector focal plane array is disclosed wherein each detector structure of the array comprises two vertically stacked quantum well layers. Each of the quantum well layers are individually biased by separate bias voltages and the separate bias voltages are modulated to produce two or more measurements at different spectral bands. Each detector structure of the array can therefore perform measurements of incident infrared energy in at least four separate spectral bands. This technique of measuring incident infrared energy in four separate spectral bands can advantageously be applied to the discrimination of hot gas sources from background infrared clutter.