One obstacle to optimizing performance of large-scale coded aperture systems operating in the diffractive regime has
been the lack of a robust, rapid, and efficient method for generating diffraction patterns that are projected by the system
onto the focal plane. We report on the use of the 'Shrekenhamer Transform' for a systematic investigation of various
types of coded aperture designs operating in the diffractive mode. Each design is evaluated in terms of its
autocorrelation function for potential use in future imaging applications. The motivation of our study is to gain insight
into more efficient optimization methods of image reconstruction algorithms.
Interest in Adaptive Coded Aperture Imaging (ACAI) continues to grow as the optical and systems engineering
community becomes increasingly aware of ACAI's potential benefits in the design and performance of both imaging and
non-imaging systems , such as good angular resolution (IFOV), wide distortion-free field of view (FOV), excellent
image quality, and light weight construct. In this presentation we first review the accomplishments made over the past
five years, then expand on previously published work to show how replacement of conventional imaging optics with
coded apertures can lead to a reduction in system size and weight. We also present a trade space analysis of key design
parameters of coded apertures and review potential applications as replacement for traditional imaging optics. Results
will be presented, based on last year's work of our investigation into the trade space of IFOV, resolution, effective focal
length, and wavelength of incident radiation for coded aperture architectures. Finally we discuss the potential application
of coded apertures for replacing objective lenses of night vision goggles (NVGs).
The design and implementation of adaptive coded apertures (diffraction) has advanced significantly since the first SPIE
conference on Adaptive Coded Aperture Imaging and Non-Imaging Sensors held in 2007. Core algorithmic concepts
relating to coding and decoding techniques remain steeply based in its non-diffractive design origins. We discuss
adaptive coded aperture imaging's current capabilities in light of recent advances as well as methods of improvement for
future systems design. The advantages of implementing reconfigurable mask patterns compared to fixed ones will also
be discussed, as well as potential improvement in angular resolution by means of reconfigurable masks.
DCS has developed an improved topographical mapping system, the 3-D Areal Mapping System. This system operates by projecting a structured multiple-line laser light array onto a target surface, temporally modulating the array, sensing the reflected light with one or more off-axis video cameras, and triangulating along the center of each line in the array. Through the use of the structured light array, an entire area of the target surface may be mapped with no movement of target or mapping system. The system's temporal modulation scheme gives it a high degree of immunity to variations in background illumination, target surface reflectivity and texture, and target topography. A holographic optical element generates the structured-light array; this element significantly reduces the size, complexity, and cost of the laser projector as compared to preceding systems and also removes certain aberrations in the projected array.
We describe a new pilot tactical training aid recently delivered to selected U.S. Marine Corps helicopter squadrons. The trainer is directed at improving targeting performance on missions supported by cockpit display of FLIR imagery. Particular features of the target identification sensor performance (TISP) trainer reported here include infrared phenomenology training, ground target identification drill, sensor controls operation training, symbology familiarization and performance prediction. Training is accomplished using real infrared imagery modified to reflect varying environmental conditions. Trainees can select the tactical scene and any of nearly 200 environmental combinations. Performance prediction graphs are then presented along with the modified images, thereby illustrating the imagery at the predicted ranges. The infrared phenomenology training further demonstrates the environmental impacts.