Application of type II W-quantum-well diode lasers for high-dynamic-temperature-range infrared scene projection

Abstract

Currently, no infrared scene projector technology has the ability to simulate the real-world, high-dynamic-range temperatures encountered by modern infrared imagers. This paper presents the application of type II W-quantum-well diode lasers used in a high-radiance mid-infrared-emitting object plane in an effort to develop the first truly high-dynamic-range infrared scene projector. The observed dynamic-range capability simulates 250 K apparent background temperature to 1100 K maximum apparent temperature for inband mid-wave 3 to 5 µm radiance. In the presented research a linear array of high-power continuous-wave mid-infrared diode lasers and a high-speed optical polygon scanner were used to produce two-dimensional projected images. The ability to simulate high apparent temperatures was the direct result of luminescent infrared radiance emitted by the diode lasers. The simulation of the low background apparent temperatures was obtained by enclosing the entire projector system in an environmental chamber operating at 232 K. The apparent temperature of the infrared scene projector was calculated analytically and compared with the measured results. Sample imagery from the high-dynamic-range infrared scene projector is also given.