Laboratory and field imaging test results on single-color and dual-band QWIP focal plane arrays

Abstract

We report on recent laboratory and field measurements on quantum well infrared photodetector (QWIP) focal plane arrays (FPAs). The results of laboratory measurements of imaging performance such as noise-equivalent temperature difference (NE ΔT), minimum resolvable temperature, conversion efficiency, uniformity of response and dark current and their dependence on operating temperature are presented on large format (640×480 pixels) single-color long-wavelength infrared (LWIR) and dual-band (256×256 pixels) mid-wavelength infrared (MWIR)/LWIR arrays. We found that under optimum operating conditions (65 K and 1 V bias), the NE ΔT of the LWIR FPA was approximately 30 mK and was limited by the optics and noise from the closed-cycle cooler. We will show field imagery of military targets taken with this FPA. In addition, field imagery taken with the LWIR QWIP camera of a large-transient event will be compared with that taken with an InSb MWIR camera. We will also show imagery of a recent total eclipse of the moon. We will also present laboratory results on a simultaneously integrating, pixel-registered dual-band FPA showing excellent operability and response uniformity with NE ΔT of approximately 30 mK in both bands ( T=60 K). The dual-band FPA was also taken to the field and we will present imagery of various targets acquired with this FPA.