John T. Caulfield

Advanced IRFPAs for next-generation sensors

Raytheon Vision Systems (RVS) has invented and demonstrated a new class of advanced focal plane arrays. These Advanced FPAs are sometimes called 3rd Generation or “Next Generation” FPAs because they have integrated onto the FPA the ability to sense multiple IR spectrums, have improved resolution and performance, and conduct image processing on the FPA ROIC. These next generation of FPAs are allowing more functionality and the detection of a more diverse set of data than previously possible with 2nd Gen FPAs. Examples and history of advanced next generation FPAs are reviewed including RVS’s Multispectral, Uncooled, Adaptive Sensors and other advanced sensors.

Signal processing on the focal plane array: an overview

Raytheons Infrared Operations (RIO) has invented and developed a new class of focal plane arrays; the Adaptive IR Sensor (AIRS) and Thinfilm Analog Image Processor (TAIP). The AIRS FPA is based upon biologically inspired on-focal- plane circuitry, which adaptively removes detector and optic temperature drift and l/f induced fixed pattern noise. This third-generation multimode IRFPA, also called a Smart FPA, is a 256x256-array format capable of operation in four modes: 1) Direct Injection (DI), 2) Adaptive Non-uniformity Correction (NUC), 3) Motion/Edge Detection, and 4) Subframe Averaging. Also the 320x240 TAIP results have shown excellent image processing in the form of Spatial and Temporal processing.

Adaptive image processing techniques for camera-on-a-chip sensors

We report on recently developed algorithms and architectures capable of point source target detection near or on the FPA. The goals of this work are to demonstrate image processing functions near or on the FPA in a manner efficient enough to allow hardwired algorithms for Camera Systems on a Chip (SOC) implementation. These SOCs have the potential to improve the size and power requirements for existing IR sensor systems which require larger board sets and hardware enclosures. We report on the algorithm development for hardwired target detection algorithms using recorded IR Data.

Bandwidth efficient sensor architectures with feature extraction

We report on processing techniques to effectively control the data bandwidth in larger format focal plane array (FPA) sensors. We have developed an image processing architecture for foveating variable acuity FPAs that give a controlled reduction in the data rate via simple circuits that estimate activity on the FPA image plane. Integrated on-FPA signal processing goals are to perform pre-processing that is usually performed downstream in a dedicated processing module. Techniques for image pre-processing described in this paper allow transmitting ldquoactiverdquo pixel data while skipping unchanging pixels. These techniques for image pre-processing adjacent to the FPA allows significant reductions in the data rate, size, weight and power for small and low cost systems that cannot work with a large image processors.