Performance Capabilities and Utilization of MICOM's Diode Laser Based Infrared Scene Projector Technology

Abstract

This paper describes the current design characteristics and performance capabilities of the US Army Missile Command's (USAMICOM's) diode laser based infrared scene projector technology. The projector is now operational at the US Army Missile Command's Research, Development, and Engineering Center (RDEC) and is being integrated into several HWIL simulation facilities. The projector is based upon a linear array of Pb-salt diode lasers coupled with a high-speed optical scanning system, drive electronics and synchronization electronics. The projector design has been upgraded to generate 256X256 resolution scenes at 4 KHz frame rates, and the fabrication of a 544X544 projector is in progress. The projector system now includes real-time non-uniformity correction electronics and is interfaced with a real-time scene generation computer. In addition, a closed-cycle cryogenic cooling system has been added for increased dynamic range and maintenance-free operation. The system's modularity provides upgradability to meet specific performance requirements such as increased spatial resolution, different emission wavelengths, or dual-band scene projection. The projector's upgraded design and performance characteristics are presented in the paper, as well as sample images generated with the projector and captured by an InSb FPA sensor.Keywords: Infrared, Scene Projection, Diode lasers, Simulation, FPA testing, Hardware-in-the-loop. INTRODUCTIONLast year we reported on the delivery of the prototype laser diode based infrared scene projector.1 The projector was developed under a Phase II SBIR contract and delivered to USAMICOM's RDEC in January 1995. Over the course of this last year the performance of the prototype projector has been evaluated by an independent user, and design modifications have been made to improve the performance of the projector. The projector is presently being customized for integration into several HWIL simulation facilities at RDEC. SYSTEM DESIGNThe projector is a laser scanning system which consists of a linear array of Tunable Diode Lasers (TDLs) coupled with a high-speed optical scanning system and drive electronics. Like other scanning projector systems, the TDL projector takes advantage of the FPA's integration mechanism. The output intensity of each TDL is temporally modulated in synchronization with the scanning mirror to effectively "paint" a two-dimensional scene across the unit-under-test's (UUT's) FOV. As the image of the TDL array is scanned across the FPA, the appropriate amount of energy is deposited onto each detector to generate the simulated scene. The projector must scan over each FPA detector at least once during its minimum integration time. In addition, the