Download or read book A Proposal to Measure the Visual Acuity in U S Army and U S Air Force Pilots and Aircrew While Wearing the AN PVS 5 and ANVIS Night Vision Goggles to Determine a Cause for Morbidity and Mortality of Aircraft Mishaps written by Warren Steven Silberman and published by . This book was released on 1991 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proposal to Measure Stereoacuity of U S Air Force Aircrew While Using the AN PVS 6 Night Vision Goggles for Use in Designing an Educational Program to Prevent Night Aircraft Mishaps written by Kenneth Karl Knight and published by . This book was released on 1995 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Night vision goggles written by United States. Congress. House. Committee on Armed Services. Subcommittee on Investigations and published by . This book was released on 1989 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Fatigue from Wearing the AN PVS 5 Night Vision Goggles on Skills Involved in Helicopter Operations written by Garvin D. Chastain and published by . This book was released on 1979 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Night Vision Goggle Field expedient Visual Acuity Adjustment Procedures written by and published by . This book was released on 1996 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Army Aviation Life Support Equipment Retrieval Program written by Samuel G. Shannon and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The relationship between night vision goggle (NVG) use in the U.S. Army and head/neck injury risk is unknown. A 10-year retrospective study of traumatic head/neck injuries among U.S. Army aircrew members wearing NVGs in rotary-wing mishaps was conducted by review of U.S. Army Safety Center and U.S. Army Aviation Epidemiology Data Register records. Among 704 cockpit aircrew members, 403 (57.2 percent) suffered some degree of injury during the mishap. Among the 403 injured crewmembers, 250 (62.0 percent) had head and/or neck injuries. A disproportionate number of cockpit aircrew members in nonsurvivable mishaps had head and/or neck injuries (87.0 percent) compared to those in survivable mishaps (19 percent). Crewmembers wearing NVGs had a significantly increased risk for head and/or neck, head only, and neck only injury. When stratified by type of NVG, and based on logistic regression models that included aircraft type (UH-60 versus other) and survivability as covariates, crewmembers wearing the AN/PVS-5 carried the burden of this injury risk (RR=2.01, Ci95-1.58.57). For crewmembers wearing the aviator's night vision imaging system (ANVIS), the risk of head and/or neck, head only, or neck only injury was not statistically greater than crewmembers not wearing NVGs (RR=l.22, c195=O.94,l.58). Aircrew wearing the older AN/PVS-5 were at increased risk for head/neck injury during a rotary-wing mishap, while ANVIS users with the ANVIS break-away feature were not at increased risk for head/neck injury.

Download or read book To See Or Not to See written by and published by . This book was released on 1975 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measuring Observers Visual Acuity Through Night Vision Goggles written by and published by . This book was released on 1998 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Use of night vision goggles (NVGs) for military applications has grown steadily over the past 30 years. Each successive NVG model represents some kind of improvement in terms of size, weight, ruggedness, gain, noise, spectral sensitivity, field-of-view or resolution. The primary focus of this paper is the determination of NVG resolution. Many methods have been devised to measure the resolving power of NVGs and each method has with it an associated variance or accuracy of measurement. This variance is most likely caused by several sources including observer visual capability (since most methods involve visual observations and judgement to assess NVG resolution). The main purpose of this paper is to present the different methods that have been used to assess NVG resolution and to determine to what extent observer visual capability limits the accuracy of NVG resolution measurement. This study uses a methodology that measures an observer's psychometric function when viewing through NVGs (percent correct detection as a function of spatial separation) to determine their visual acuity using probit analysis.

Download or read book Comparative Visual Performance with Anvis and AN PVS 5A Night Vision Goggles Under Starlight Conditions written by Wayne F. Provines and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Prevalence of Astigmatism Among Aviators and Its Limiting Effect Upon Visual Performance with the AN PVS 5 Night Vision Goggles written by Hanson J. Kim and published by . This book was released on 1982 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emphasis on sustained operations during periods of darkness is steadily increasing. Presently, the AN/PVS-5 Night Vision Goggles (NVG) are utilized for night operations. The primary concern with these goggles is the astigmatism criterion since this, unlike spherical refractive errors, is not compensated by the NVG. The NVG have only an adjustable range of +2.00 to -6.00 diopters to correct for spherical error. No provisions were incorporated into the design of the NVG to allow correction of astigmatic error. Consequently, an aviator with a significant amount of astigmatism will have reduced visual acuity which will affect his operational performance. A study was undertaken to identify the number of rated aviators at the Army Aviation Center with detected astigmatism in order to assess the magnitude of this particular problem and to determine whether or not the current standards for astigmatism are sufficient for the aviators who are using the AN/PVS-5 Night Vision Goggles.

Download or read book Comparative Visual Performance with ANVIS Aviator s Night Vision Imaging System and AN PVS 5A Night Vision Goggles Under Starlight Conditions written by R. E Miller (III.) and published by . This book was released on 1984 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental testing of 10 subjects wearing the AN/PVS-5A (II GEN) night vision goggles (NVG) and ANVIS (III GEN) NVG was conducted under field conditions of ambient starlight illumination (approx. 10-5 mL). The parameters measured were: 1) binocular visual acuity (BVA), 2) stereopsis (depth perception), and 3) a subjective forced choice test. Results showed that BVA was 20/124 and 20/86 for the II and III GEN NVG, respectively. This difference was statistically as well as clinically significant. The stereopsis test results were inconclusive and variable because of the limited sample size and relative inexperience of the subjects in using NVG. Neither BVA nor stereopsis with the NVG was found to be related to standard baseline measures of these parameters in the clinic. Even though the ANVIS has better gain, resolution and sensitivity, 6 out of 10 subjects preferred the AN/PVS-5A for viewing the subjective test. This seemingly paradoxical finding was surmised to be a result of the presence or lack of scene contrast due to the differential sensitivities in the II and III GEN photocathode tubes.

Download or read book Visual Acuity for High Contrast Tri bar Targets Illuminated with Spectra Simulating Night Vision Goggle NVG Displays and the No moon Night Sky written by and published by . This book was released on 2010 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents two studies that measured unaided visual acuity using a 50-in square high-contrast U.S. Air Force (USAF) 1951 Tri-Bar chart viewed from 12 ft at luminance levels ranging from 0.00046 fL (much darker than a night vision goggle [NVG] display of an overcast starlight scene) to 21.5 fL (much brighter than a NVG display of a full-moon scene). To avoid visual noise artifacts, these studies did not use actual NVG displays. The studies were designed to support general modeling efforts at the U.S. Army Research Development and Engineering Command (RDECOM) Communications-Electronics Research Development and Engineering Center (CERDEC), Night Vision and Electronic Sensors Directorate (NVESD). For Study 1, the Tri-Bar chart was back-lit with a spectrum similar to the standard yellowish-green (P43) phosphor NVG display. In Study 2, the chart was back-lit with tungsten illumination, similar to a 2856 K blackbody spectrum. In addition to providing measures of unaided visual acuity, we introduced a new technique-the Green-appearance Scale-to determine the luminance levels at which participants transitioned from scotopic viewing of the Tri-Bar chart to mesopic viewing, and from mesopic viewing to photopic viewing. We describe this technique and present the data as part of the methodology and results of Study 1.

Download or read book Night Vision Goggle Field Expedient Visual Acuity Adjustment Procedures Initial Experiment written by and published by . This book was released on 1996 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The third-generation image intensification technology in night vision goggles (NVGs) used by ground forces provides at best 20/40 or 20/45 visual acuity. These acuity levels cannot be achieved unless soldiers adjust their NVGs properly. Documentation available to soldiers does not address optimum adjustment techniques developed by the aviation community nor does it address what can be used in the field to achieve a good setting. We examined the effectiveness and utility of 15 different objects commonly available to soldiers to determine which provided the best visual acuity readings with the AN/PVS-713 NVGs. After training and practice acuity improved by 25% over the baseline assessment. No large differences in readings occurred among the objects. However, a more definitive picture emerged when the average readings were combined with measures of variability and soldier preferences. The initial recommendation is to use one of the following objects for NVG adjustment: trec trunk, vehicle, vehicle trail, stars, blue chem light, or an infrared chem light. Not recommended are bright and/or red light sources, white paper, and trees silhouetted against the night sky. Problems in assessing acuity with NVGs are also discussed.

Download or read book Attenuating the Luminous Output of the AN PVS 5A Night Vision Goggles and Its Effects on Visual Acuity written by Richard R. Levine and published by . This book was released on 1989 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aviators in combat may be subjected to a variety of noxious light stimuli. Filters and other eye protective devices may be used to counter these threats. At night, filters may be used in conjunction with image intensification devices (e.g., night vision goggles) to provide useful low-light vision as well as protection from deleterious light sources (e.g., lasers, pyrotechnics, nuclear fireballs, etc.). Technologies may be combined in a single, integrated head gear unit. The present study was performed in order in consider the effects on visual acuity after reducing night vision goggle luminous output from 0-99 percent. A range of target contrasts and ambient illumination levels was investigated. AN/PVS-5A goggles were selected based upon their compatibility with current phosphor display technology and their current ubiquity within aviation units. Visual acuity was assayed behaviorally because of its critical importance in flying performance. The results of the study provide normative acuity data with goggles alone and document the effects on goggle visual acuity with reduce goggle luminances as might be produced by protective materials placed between the goggles and the eyes. Keywords: Light filters; Human factors engineering; Night vision devices.

Download or read book Effect of Incompatible Light on Modified Class B Night Vision Goggle aided Visual Acuity and Contrast Sensitivity written by Randall W. Gibb and published by . This book was released on 1997 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: MIL-L-85762A, Lighting, Aircraft, Interior, Night Vision Imaging System (NVIS) Compatible, defines criteria for assessing night vision goggle (NVG) compatibility of cockpit lighting. As part of the assessment procedures, NVG aided visual acuity (VA) is measured using the USAF Tri-Bar Chart. A cockpit light is incompatible if NVG aided VA is degraded. An alternative method of measuring NVG aided VA uses an NVG Chart. This research assessed whether the two NVG aided VA assessment techniques reveal the same levels of degradation in NVG aided VA. NVG aided contrast sensitivity (CS) also was measured to determine its usefulness in assessing the compatibility of a cockpit light. Three NVG CS charts were developed having spatial frequencies of 3, 6, and 12 cycles per degree (cpd). NVG performance was degraded by incompatible light, and the amount of degradation was assessed using the two VA and CS measures. Measurements were made using a modified Class B NVG. Another objective of this research was to assess the compatibility of the modified Class B NVG with compatible cockpit light defined in MIL-L-85762A. The results revealed that NVG aided VA did not differ between the two VA charts. For the green light, NVG aided CS was degraded only for the high spatial frequency (12 cpd). However, for the red light, NVG aided CS was degraded for all three spatial frequencies. NVG aided CS was sensitive to the presence of incompatible light. The modified Class B NVG is compatible with the lighting requirements defined in MIL-L-85762A.

Download or read book Comparative Night Vision Goggle Visual Acuity Measurements Performed in the A 10 Aircraft in an Operational Setting written by and published by . This book was released on 1993 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Night Vision Programs Office of the Aircrew Training Research Division, Armstrong Laboratory, responded to a request from the 422nd Operational Test Squadron at Nellis AFB to conduct the ground testing portion of their A-10 Night Vision Goggle (NVG) special project. Evaluations were conducted comparing the performance of four different NVGs under both laboratory and representative operational conditions. The performance of the F4949 'Super ANVIS' was superior to that of the other NVGs tested. Additionally, a comparative study was conducted evaluating the impact of two different windscreens on NVG image quality. The new windscreen allowed the transmission of more energy usable to the NVGS, thus enhancing image quality over that possible with the old windscreen ... Adjustment procedures, Night vision goggles, Transmissivity, Compatible cockpit lighting, NVD, Visual acuity, Night vision devices, NVG.

Download or read book Night Vision Goggle Assessment Techniques with Incompatible Cockpit Lighting and a Modified Class B Goggle written by Randall William Gibb and published by . This book was released on 1996 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: