The human visual perception performance results of a dual band near (intensified) and long wave (thermal imager)
sniper scope are modeled. This system combines an uncooled focal plane array based thermal imager with an intensifier
tube to provide a dual band image. The resulting fused image can obtain any percentage combination of thermal or
intensified imagery. A multi-spectral common aperture is utilized to provide parallax free registered images in each
spectrum necessary for the sniper scope application. A custom designed eyepiece with a micro display overlays the
thermal channel image onto the intensified image. The intensified image is viewed directly on the fiber optic output of
the intensifier allowing up to 64lp/mm intensified resolution, equivalent to 2300 resolvable lines maintained in the
intensified channel when moonlight is available. A system of this type combines the very high line resolution available
from intensifiers with very high spot detection for targets of military interest. The results of an analysis of human visual
performance using NVThermIP and IINVD are presented for this dual band common aperture sniper scope.
This paper discusses the depth acuity research conducted in support of the development of a Modular Multi-Spectral Stereoscopic (M2S2) night vision goggle (NVG), a customizable goggle that lets the user select one of five goggle configurations: monocular thermal, monocular image intensifier (I2), binocular I2, binocular thermal, and binocular dual-waveband (thermal imagery to one eye and I2 imagery to the other eye). The motives for the development of this type of customizable goggle were (1) the need for an NVG that allows the simultaneous use of two wavebands, (2) the need for an alternative sensor fusion method to avoid the potential image degradation that may accompany digitally fused images, (3) a requirement to provide the observer with stereoscopic, dual spectrum views of a scene, and (4) the need to handle individual user preferences for sensor types and ocular configurations employed in various military operations. Among the increases in functionality that the user will have with this system is the ability to convert from a binocular I2 device (needed for detailed terrain analysis during off-road mobility) to a monocular thermal device (for increased situational awareness in the unaided eye during nights with full moon illumination). Results of the present research revealed potential depth acuity advantages that may apply to off-road terrain hazard detection for the binocular thermal configuration. The results also indicated that additional studies are needed to address ways to minimize binocular incompatibility for the dual waveband configuration.
An adaptive laser communication system capable of minimizing the impact of atmospherically induced tip-tilt and defocus distortions and tracking an optical antenna mounted on a mobile platform is presented. The laser communication system consists of two independently operating adaptive optical transceivers mounted on wide angle pan-tilt gimbals that each transmit and receive optical data propagating on a single bidirectional laser beam. Each optical antenna incorporates a 3-channel tip-tilt and defocus adaptive mirror constructed at the Army Research Laboratory. The adaptive mirror control system of each optical transceiver is based on phase control of the outgoing wavefront by stochastic parallel gradient descent optimization of the optical power received by the other optical transceiver. A tracking capability of an optical transceiver mounted on a mobile platform is implemnted by using the pan-tilt control signals of each adaptive mirror to define signals that drive the pan-tilt axes of the gimbal on which the adaptive mirror is mounted. System performance in the presence of laboratory generated turbulence is characterized and reported. Results demonstrate that the adaptive laser communication system can reduce signal fading induced by atmospheric tip-tilt distortions and improve the concentration of laser beam energy delivered to each optical transceiver and therefore reduce system bit error rates.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.