Historically, the natural structure of Indium Gallium Arsenide backside illuminated FPAs has allowed them to detect
light with wavelengths between 0.9 and 1.7 μm. However, new wafer growth and processing methods have allowed
extended response InGaAs imagers to be used in high sensitivity cameras to detect light down to 0.7 μm. These
extended response imagers hold many advantages over standard cut-on InGaAs.
One of these advantages is being able to detect beacons, lasers, and illuminators in the 800-900 nm range, light sources
that have historically only been detectable with I<sup>2</sup>CCD cameras or night vision tubes, while simultaneously being able to
detect the longer wavelength convert illuminators and lasers. Another advantage is capturing any additional available
photons with wavelengths between 0.7 μm and 0.9 μm. This improves overall imaging capability in most low light level
This paper will address the methods used to achieve stable, high sensitivity extended response imagers, as well expand
on the applications of this breakthrough.
The design, development, and characterization of a new, low-power, wide operating temperature range miniature short wave infrared (SWIR) camera for military applications is described in this paper. Such applications typically require operation over an extended(<-35C to >65C) temperature range. The camera technology is based on standard indium-gallium-arsenide (InGaAs) focal plane array (FPA) technology, but eliminates the thermal electric cooler (TEC) to both expand the operating temperature range and minimize power consumption. To compensate for variable FPA temperature, new algorithms were conceived and implemented in real time camera hardware resulting in a camera with an operating temperature range wider than that possible by stabilizing with a single stage peltier cooler. The additional benefit is reduced power consumption at temperature extremes and concomitant reduction in required thermal management. Imagery and results will be presented from 320x256 and 640x512 arrays.