Search

Numerous infrared scene projection technologies have been investigated since the 1970s. Notably, from the late 1980s the development of the first resistor array infrared projectors gained leverage from the strong concurrent developments within focal plane array imaging technology, linked by the common need for large integrated circuits comprising a 2-dimensional array of interconnected unit cells. In the resistor array case, it is the unit cell comprising the resistively heated emitter and its dedicated drive circuit that determines the projector response to its associated scene generator commands. In this paper we review the development of resistor array technology from a historical perspective, concentrating on the unit cell developments. We commence by describing the technological innovations that forged the way, sharing along the way stories of the successes and failures, all of which contributed to the steady if somewhat eventful growth of the critical knowledge base that underpins the strength of today's array technology. We conclude with comments on the characteristics and limitations of the technology and on the prospects for future array development.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An addressable mosaic array of resistively heated microbridges offers the potential to project accurate dynamic infrared (IR) imagery. The main purpose of this imagery is to be used in the evaluation of IR instruments from seekers to FLIRs. With the growing development of lower cost uncooled IR imagers, scene projectors also offer the potential for dynamic testing of these new instruments. In past years we have described developments in a variety of IR projectors systems designed for different purposes. In this paper we will describe recent developments in these technologies aimed at improving or understanding temporal and radiative performance.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Kinetic energy weapon (KEW) programs under the Ballistic Missile Defense Office (BMDO) need high fidelity, fast framing infrared (IR) imaging seekers. As imaging sensors have matured to support BMDO, the complexity of functions assigned to the KEW weapon systems has amplified the necessity for robust hardware-in-the-loop (HWIL) simulation facilities to reduce program risk. Tactical weapon systems are also turning to imaging focal plane array (FPA) seekers. They too require more sophisticated HWIL testing. The IR projector, an integral component of a HWIL simulation, must reproduce the real world with enough fidelity that the unit-under-tests's (UUT) software will respond to the projected scenario of images as though it were viewing the real world. The MOSFET resistor array IR scene projector shows great promise in cryogenic vacuum chamber as well as room temperature testing. Under the wideband infrared scene projector (WISP) program, an enhanced version of the resistor array is currently under development. When the WISP system is delivered, the projector will consist of a 512 by 512 baseline array with the center 128 by 128 resistors having a higher output capability. For the development stage of the program, 512 by 512 prototype baseline and 128 by 128 prototype high dynamic range (HDR) arrays have been fabricated separately. Characterization measurements to include: spectral output, dynamic range capability, apparent temperature, rise time, fall time, cross talk, and current consumption have been accomplished on the prototype baseline and HDR arrays at the Kinetic Kill Vehicle Hardware-in-the-Loop Simulator (KHILS) Facility and the Guided Weapons Evaluation Facility (GWEF). Results from the measurements show the HDR array dynamic range is an order of magnitude greater than its predecessor. Other parameters such as droop, rise time, etc., either meet or are close to meeting system specifications. The final design of the arrays is currently in progress based on these results.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An addressable mosaic array of resistively heated microbridges offers much flexibility for infrared scene simulations. In the Wide Band Infrared Scene Projector program, Honeywell has demonstrated high yield arrays up to size 512 X 512 capable of room temperature operation for a 2 band infrared projection system being designed and built by Contraves Inc. for the Wright Laboratory Kinetic Kill Vehicle Hardware In-the-Loop Simulator facility at Eglin Air Force Base, FL. The arrays contain two different pixel designs, one pixel designed for kHz frame rates and high radiance achieved at a power level of 2.5 mWatts/pixel and the other pixel designed for more moderate 100 Hz frame rates at lower radiance and at maximum power levels of 0.7 mWatts/pixels. Tests on arrays and pixels have demonstrated dynamic ranges up to 850:1, radiance rise times on the order of 2 mseconds, and broadband pixel emissivities in the range of 70%. Arrays have been fabricated with less than 0.1% pixel outages and no row or column defects. These arrays are mounted in a specialized vacuum assembly containing an IR window, vacuum package, cooling block, and pump out manifold.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Kinetic energy weapon (KEW) programs under the Ballistic Missile Defense Office (BMDO) need high fidelity, fast framing infrared (IR) imaging seekers. As imaging sensors have matured to support BMDO, the complexity of functions assigned to the KEW weapon systems has amplified the necessity for robust hardware-in-the-loop (HWIL) simulation facilities to reduce program risk. The IR projector, an integral component of a HWIL simulation, must reproduce the real world with enough fidelity that the unit under test's (UUT) software will respond to the projected scenario of images as though it were viewing the real world. The CMOS resistor array IR scene projector, a wideband flickerless technology, shows great promise in cryogenic vacuum chamber as well as room temperature testing. A 128 X 128 CMOS resistor array has undergone extensive characterization measurements at Eglin AFB to determine its potential for HWIL testing of BMDO IR seekers. This paper addresses the nonuniformity correction (NUC) and use of the array in a calibrated projection test. The methodology and process for the NUC is described. Sensitivities to such things as output averaging, and optical sampling are explained. With the NUC procedure established, a test was accomplished that provided calibrated scene radiance values to a UUT. Absolute radiance values were not projected. Rather, the array's low and high output capabilities were equated to the low and high radiance values of an input scene. A calibration curve was established that allowed the UUT's output to be equated to the input scene's radiance values. The input scene was projected to the UUT, and the scene's radiance values were reproduced after applying the calibration curve to the UUT's output response. To the authors' knowledge, this if the first accomplishment of such a test with a dynamic IR scene projector.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.