Showing papers on "Night vision published in 1970"

Effects of Continuous Military Operations on Selected Military Tasks

Abstract: : New devices and sensors for night seeing and target acquisition have increased the capability of the U. S. Army for continuous operation extending through day and night. Although the soldier can continue to function under such conditions, his performance on critical tasks may be so degraded that his effectiveness is severely impaired. The present research was undertaken to determine the extent to which soldier performance is degraded on combat-related tasks, with the goal of developing techniques, work methods, and procedures for reducing such degradation if it occurs.

Prismatic adaptation under scotopic and photopic conditions.

Abstract: Prismatic adaptation under scotopic and photopic conditions in subjects, using transfer experiments

Visual requirements in night driving

Abstract: FOUR STUDIES WERE MADE TO ASSESS THE KIND AND INTENSITY OF VISUAL DATA PRESENTED TO THE DRIVER DURING NIGHTTIME DRIVING. A STUDY OF HIGHWAY LUMINANCE AND VEHICLE CONTROL SHOWED THAT A DRIVER CAN PERFORM REMARKABLY WELL WITH ONLY ONE PERCENT OF NORMAL NIGHTTIME LUMINANCE. IN THE SECOND STUDY, VISIBILITY WAS MORE SEVERELY DEGRADED, THE DRIVER BEING ALLOWED ONLY A SMALL AREA OF THE ROAD BY WHICH TO DRIVE. VELOCITY SELECTION WAS FOUND TO BE A FUNCTION OF DISTANCE TO AVAILABLE IMFORMATION AND VELOCITY MAINTENANCE OF THE ANGLE OF INFORMATION. LAMPS LOCATED ABOUT 75 FEET AWAY PRODUCED THE LOWEST VARIABILITY IN VELOCITY AND STEERING-WHEEL MOVEMENTS AND THE HIGHEST AVERAGE VELOCITY. WHEREAS LANE MARKERS WERE USED FOR TRACKING BECAUSE OF THEIR HIGH CONTRAST, THERE WAS NO TENDENCY TOWARD TRACKING ON UNLINED ROADS REGARDLESS OF LAMP PLACEMENT. THE THIRD STUDY WAS LARGELY THE SAME AS THE SECOND BUT PARTITIONED THE FIELD OF VISION. AGAIN, SUBJECTS PREFERRED INFORMATION 75--100 FEET AWAY FOR VELOCITY SELECTION, AND DRIVER ALLOWANCE FOR TIME WAS NEARLY LINEAR WITH RESPECT TO PREVIEW DISTANCE AND VELOCITY. THE FINAL STUDY WAS DIRECTED TOWARD EYE MOVEMENTS IN DAYTIME AND NIGHTTIME DRIVING. DRIVERS TENDED TO DRIVE AT NIGHT WITH THEIR FOCUS CLOSER IN FRONT OF THE VEHICLE THAN IN DAYTIME.

Low light level tracer mix

Abstract: A LOW LIGHT LEVEL, LONG-BURNING, SMALL ARMS TRACER PYROTECHNIC MIXTURE FOR USE WITH NIGHT VISION EQUIPMENT COMPRISING, BY WEIGHT PERCENT: STRONTIUM PEROXIDE, 10-90; BARIUM PERIOXIDE, 0-65; CALCIUM RESINATE, 5-15; AND MAGNESIUM CARBONATE, 10-15.

Some effects of lateral sign displacement

Abstract: THE EFFECT OF INCREASING THE LATERAL OFFSET OF HIGHWAY SIGNS ON THE LEGIBILITY OF THESE SIGNS WAS ANALYZED. AN APPROACH BASED ON HIGHWAY GEOMETRICS AND HUMAN VISION WAS EMPLOYED. HIGHWAY CURVES AS WELL AS TANGENT SECTIONS WERE ANALYZED. IT WAS FOUND THAT LARGER LETTER SIZES WERE INDICATED WITH INCREASED OFFSET DISTANCES AND THAT CERTAIN COMBINATIONS OF HORIZONTAL CURVATURE AND OFFSET WOULD RESULT IN THE SIGN FALLING ENTIRELY OUTSIDE THE NORMAL FIELD OF VISION. THE EFFECT OF THE LATERAL OFFSET ON NIGHT LEGIBILITY OF SIGNS, WHEN THE SIGNS ARE ILLUMINATED BY HEADLIGHT ONLY, WAS ALSO INVESTIGATED. A COMPUTER PROGRAM WAS DEVELOPED TO INVESTIGATE THE RELATIONSHIP OF THE FIVE PERTINENT VARIABLES: DEGREE OF CURVATURE, APPROACH SPEED, MAXIMUM DIVERGENCE ANGLE, MESSAGE CONTENT, AND LETTER SIZE. /AUTHOR/

Airborne Measurements of Optical Atmospheric Properties at Night

Abstract: : This report presents atmospheric optical data collected at night in Thailand chiefly with airborne instruments during two field expeditions, one trip made during the wet monsoon season and one during the dry season. Results from eighteen flights are presented. The data include irradiance, directional reflectance of backgrounds, total scattering coefficients, atmospheric beam transmittance, path radiance, and directional path reflectance. Data for starlight, moonlight, and overcast conditions were derived for downward-looking paths of sight inclined at seven zenith angles (93, 95, 100, 105, 120, 150, and 180 degrees) from altitudes of 1524 m and lower in five spectral regions, as follows: four narrow band optical filters with maximum transmittances at 475, 515, 660, and 745 nm; one broad band sensitivity representing the S-20 multiplier phototubes fitted with UV reflection filter. Simultaneous photoelectric (Royco) measurements of the distributions of atmosphere particle sizes are reported.

A Study of Individual Variability in Dark Adaptation and Night Vision in Man

Abstract: : The report provides a comprehensive analysis of the significance of individual variation in human night vision capability It reviews the origin and magnitude of inter- and intra-individual variation in the several physiological and behavioral processes that constitute dark adaptation and scotopic vision the genetic, somatic, and behavioral factors that exhibit variation and the environmental factors affecting variation are discussed The report identifies gaps in this knowledge that bear on the requirements for efficient night vision in the soldier The report suggests that recognition of individual variation is critical to the concept of selecting key individuals for specific duties requiring night vision capability

Night-vision training goggles

Abstract: A night-vision training goggles lens formed as a unitary piece covering both eyes from a single thickness of a press-polished, dark-green-transparent sheet of synthetic resin having a color response providing a visual transmittance peak at a wave length between 5400 A. and 5600 A. and having an optical density between six and seven.

Search Effectiveness with Passive Night Vision Devices

Abstract: : Performance with four devices was evaluated in the experimental procedure: the Miniscope (MINI), Starlight Scope (SS), Crew-Served Weapon Night Vision Sight (CSWS), and the Night Observation Device, Medium Range (NOD). At a rate of nine per night, 123 operators were tested under three varied ambient illumination levels in the search and detection of 72 targets which differed in type, contrast, and mode and which were stationed at a distance of 100 to 1200 meters. Detection responses and search behavior were recorded on magnetic tape for data analysis.

Subjective comparison of the use of contact lenses and spectacles for driving

Abstract: CONTACT LENSES, AS WELL AS SPECTACLES, HAVE ADVANTAGES AND DISADVANTAGES WHEN WORN FOR DRIVING. THE FOLLOWING POINTS SHOULD BE GIVEN SPECIAL CONSIDERATION: ADVICE ON SUNSPECTACLES AND EYE PROTECTORS SHOULD BE GIVEN ACCORDING TO THE TYPE OF VEHICLE TO BE DRIVEN; FITTING TECHNIQUES SHOULD BE USED WHICH CAUSE MINIMUM ALTERATION TO REFRACTION AND NO CORNEAL EDEMA, SO THAT IF CONTACT LENSES HAVE TO BE REMOVED VISION IN SPECTACLES IS SATISFACTORY FOR DRIVING; ALL PATIENTS WHO DRIVE SHOULD BE INSTRUCTED TO CARRY WITH THEM AN UP-TO-DATE SPECTACLE CORRECTION IN A FRAME WHICH DOES NOT OBSTRUCT THE VISUAL FIELD; AND LENSES SHOULD BE FITTED WHICH ARE BIG ENOUGH IN THE APPROPRIATE DIMENSIONS TO MINIMIZE FLARE AND HALOS, AND OF SUITABLE POWER TO ALLOW FOR NIGHT MYOPIA. /AUTHOR/

An investigation of chromatic glare with particular reference to night driving

Abstract: THE EFFECTS OF GLARE FROM DIFFERENT COLORED SOURCES ARE INVESTIGATED UNDER CONDITIONS SIMULATING THOSE OF NIGHT DRIVING. DIFFERENCES WERE OBSERVED IN THE EFFECTS FROM BLUE, GREEN, RED AND WHITE SOURCES. THE RESULTS SUGGEST THAT DIFFERENT ENTOPIC STRUCTURES ARE RESPONSIBLE FOR SCATTERING DIFFERENT PREDOMINANT WAVELENGTHS. CHANGES IN THE PRACTICAL PARAMETERS IN STREET LIGHTING ARE CONSIDERED TOO GREAT TO ENABLE GLARE TO BE SYSTEMATICALLY REDUCED BY SPECIFYING A PREFERRED CHROMATICITY. /RRL/

Human performance experimentation in night operations: technology and instrumentation for field research

Abstract: : The NIGHT OPERATIONS program is concerned with problems in optimizing human performance in relation to night vision devices and related sensors. The present publication provides a description and evaluation of the effectiveness of an instrumentation system developed under concepts provided by BESRL research scientists. The primary objective in this phase of the research was to develop an instrumentation system, embodying the requirements and essential characteristics for effective and accurate measurement of target detection and search behavior in field testing.

Fluorescence Properties of Visual Pigmentsla

Abstract: The act of seeing, i.e. vision, requires a chromophore capable of absorbing light. In a continuing series of studies Wald, Hubbard, and co-workers2 have shown that this visual pigment is formed from the combination of a protein with a particular polyene aldehyde. By far the greatest attention has been centered on the night vision pigment, rhodopsin. Its chromophore is derived from 11-cis retinal by reaction of the aldehyde group with a specific amino group on the protein3 (although there is some controversy over this point4). Further, the spectral properties of rhodopsin are best reconciled with the protonated (or acidified) form of this Schiff base.5

Search effectiveness with the starlight scope and 7 x 50 binoculars

Abstract: : The night operations program is concerned with problems in optimizing human performance in relation to night vision devices and related sensors. To further this research, experimentation has been directed toward enhancement of the performance of the combat soldier in night operations. The report describes an experimental evaluation or four passive night vision devices, and presents results of the assessment of operator performance with these devices in target detection and search tasks. Subjects were required to detect targets (soldiers or aggressor type silhouettes) presented in two modes. Responses were recorded electronically. Data obtained were analyzed to determine performance effectiveness with the two subject devices and the effects were studied of illumination (starlight, half moon, full moon), distance (50 - 300 meters), target mode (moving vs stationary), target exposure time (10, 20, 30 and 90 seconds), and their interactions on search performance.