Bolometers running backward: the synergy between uncooled IR sensors & dynamic IR scene projectors

Abstract

The leading IR scene projection (IRSP) device technology, resistive emitter arrays, has grown from its early roots in the uncooled microbolometer community into a separate and highly specialized field of its own. IRSP systems incorporating "microbolometers running backwards" are critical tools now ubiquitous in laboratory testing and evaluation of high performance IR sensors and their embedded algorithms. Adoption of IRSPs has reduced the scope of flight/field testing, producing dramatic resource savings and strong system development advantages. Modern IRSP systems provide the capability to project high-resolution (1024 x 1024), high-temperature (750 K) dynamic MWIR-LWIR imagery at frame rates up to 200 Hz, with 16-bit input resolution. Novel IRSP systems are now being developed to test advanced FPAs and sensors requiring wide-format (768 x 1536), cryogenic background (50-80 K), fast-framing (400 Hz), and/or very high-temperature (2500 K) dynamic IR simulation in order to be properly evaluated. The ongoing cycle of sensor improvement and test system evolution is perfectly illustrated by the parallel development of IRSP and emerging FPA/sensor technologies. The cross-pollination of technology between the sensor and projector domains continues to bring innovation to both communities. Technological trends related to semiconductor and microelectrical-mechanical system (MEMS) device fabrication, real-time digital video processing, and EO system design are being exploited by both sensor and projector developers alike - with advantages realized by both. This paper presents a lighthearted overview of the technical evolution of IRSP from its early microbolometer roots, discusses current and emerging IRSP capabilities, illustrates the device-level to system-level synergy between sensors and projectors, and offers a peek into the advanced EO simulation capabilities and technologies which will be required to address emerging FPA and sensor trends.