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
A dynamic infrared (IR) scene projector which is based upon diode lasers is now operational at the US Army Missile Command's (MICOM) Research, Development, and Engineering Center (RDEC). The projector is referred to as the Laser Diode Array Projector (LDAP). It utilizes a 64-element linear array of Pb-salt diode lasers coupled with a high-speed optical scanning system, drive electronics and synchronization electronics to generate in-band IR scenes. The projector is interfaced to a real-time scene generation computer which is capable of 3-D scene generation. This paper describes the process for calibration of the projector and the correction of spatial non-uniformities which are inherent in the projector design. Each laser within the system must be calibrated so that its output power is linear with respect to input gray level. The calibration table for each laser is stored in the projector electronics memory and is applied in real-time. In addition, spatial variations in perceived pixel intensity must be corrected such that the output scene is uniform. Gain and offset correction factors for each pixel are used to correct the spatial non-uniformities. The gain and offset terms are applied to each pixel in real-time by the projector drive electronics. The projector's overall performance characteristics, including the non-uniformity correction (NUC) performance level achieved to-date, are presented in the paper. Issues associated with NUC limitations are also discussed. Sample images generated with the projector and captured by an InSb FPA sensor are included in the text.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.