Visual Acuity for High-Contrast Tri-bar Targets Illuminated with Spectra Simulating Night Vision Goggle (NVG) Displays and the No-moon Night Sky

2010 ◽  
Author(s):  
V. G. CuQlock-Knopp ◽  
Edward Bender ◽  
John Merritt ◽  
Jennifer Smoot
Keyword(s):  
Visual Acuity ◽  
Night Vision ◽  
High Contrast ◽  
Night Sky

scholarly journals Visual acuity through Night Vision Goggles (NVGs): A comparative assessment between Gen 2++ and Gen 3 NVGs under different illumination conditions

2021 ◽  
Vol 65 ◽  
pp. 17-22
Author(s):  
D Sharma ◽  
NK Tripathy ◽  
V Raghunandan ◽  
BM Sekhar
Keyword(s):  
Visual Acuity ◽  
Full Moon ◽  
Night Vision ◽  
Dynamic Changes ◽  
Operational Conditions ◽  
Measure Design ◽  
Image Intensification ◽  
Night Sky ◽  
The Difference ◽  
Better Than

Introduction: During night flying operations, Night Vision Goggles (NVGs) help the aircrew to visualize by intensifying lights reflected from an object. Night sky illumination and image intensification mechanism are the two important factors that affect visual acuity (VA) through NVG. Hence, assessment of visual acuity through Gen 2++ and Gen 3 NVG under different illumination conditions and comparative analysis between the two NVGs was the desired objective of the study. Material and Methods: In a prospective repetitive measure design, a total of 60 volunteered subjects were examined for their VA through Gen 2++ and Gen 3 NVGs using USAF Tri-Bar Chart in the eye lane room of the NVG Lab. The VA was measured under four different illumination conditions; full moon (FM), half moon (HF)quarter moon (QM), and starlight (SL) conditions. The measured VA was converted to logMAR values and analyzed. Results: VA deteriorated significantly with decreasing illuminations through both Gen 2++ (χ2 = 149.9, P < 0.001) and Gen 3 NVGs (χ2 = 156.5, P < 0.001). For Gen 2++ NVG, the difference in VA was statistically significant in all conditions other than between FM and HM. Whereas, it was almost significant for all illumination conditions for Gen 3 NVG. The VA through Gen 2++ was better than Gen 3 in all conditions and the difference in VA widened with decreasing illuminations. Conclusion: VA declined with decreasing illuminations for Gen 2++ as well as Gen 3 NVG, even though, the difference was not significant between FM and HM for Gen 2++ NVG. VA was observed to be consistently better through Gen 2++ NVG compared to Gen 3 across all four illumination conditions. However, keeping in view the dynamic changes in night sky illuminations during flying operations, the findings of the study need to be validated in operational conditions.

Reproducibility of Night Vision Goggle Visual Acuity Measurements Using Landolt C's

1999 ◽  
Author(s):  
Alan Pinkus ◽  
H. L. Task ◽  
Sharon Dixon ◽  
Charles Goodyear
Keyword(s):  
Visual Acuity ◽  
Night Vision

scholarly journals Minimum Detectable Change of Visual Acuity Measurements Using ETDRS Charts (Early Treatment Diabetic Retinopathy Study)

2021 ◽  
Vol 18 (15) ◽  
pp. 7876
Author(s):  
María Carmen Sánchez-González ◽  
Raquel García-Oliver ◽  
José-María Sánchez-González ◽  
María-José Bautista-Llamas ◽  
José-Jesús Jiménez-Rejano ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Diabetic Retinopathy ◽  
Early Treatment ◽  
High Reliability ◽  
Minimal Detectable Change ◽  
High Contrast ◽  
Detectable Change ◽  
Low Contrast ◽  
Minimum Detectable Change ◽  
The Mean

In our work, we determined the value of visual acuity (VA) with ETDRS charts (Early Treatment Diabetic Retinopathy Study). The purpose of the study was to determine the measurement reliabilities, calculating the correlation coefficient interclass (ICC), the value of the error associated with the measure (SEM), and the minimal detectable change (MDC). Forty healthy subjects took part. The mean age was 23.5 ± 3.1 (19 to 26) years. Visual acuities were measured with ETDRS charts (96% ETDRS chart nº 2140) and (10% SLOAN Contrast Eye Test chart nº 2153). The measurements were made (at 4 m) under four conditions: Firstly, photopic conditions with high contrast (HC) and low contrast (LC) and after 15 min of visual rest, mesopic conditions with high and low contrast. Under photopic conditions and high contrast, the ICC = 0.866 and decreased to 0.580 when the luminosity and contrast decreased. The % MDC in the four conditions was always less than 10%. It was minor under photopic conditions and HC (5.83) and maximum in mesopic conditions and LC (9.70). Our results conclude a high reliability of the ETDRS test, which is higher in photopic and high contrast conditions and lower when the luminosity and contrast decreases.

scholarly journals Night vision in barn owls: Visual acuity and contrast sensitivity under dark adaptation

2012 ◽  
Vol 12 (13) ◽  
pp. 4-4 ◽  
Author(s):  
J. Orlowski ◽  
W. Harmening ◽  
H. Wagner
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Dark Adaptation ◽  
Night Vision ◽  
Barn Owls

Distracted Driving and Driving Patterns in Older Drivers With Glaucoma

2021 ◽  
pp. 155982762110428
Author(s):  
Purva Jain ◽  
Jonathan T. Unkart ◽  
Fabio B. Daga ◽  
Linda Hill
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Fields ◽  
Distracted Driving ◽  
Night Vision ◽  
Driving Ability ◽  
Safe Driving ◽  
Ability To Drive ◽  
Acuity Score

Limited research exists examining self-perceived vision and driving ability among individuals with glaucoma, and this study assessed the relationship between glaucoma, visual field, and visual acuity with driving capability. 137 individuals with glaucoma and 75 healthy controls were asked to evaluate self-rated vision, self-perceived driving ability, and self-perceived distracted driving. Visual acuity and visual field measurements were also obtained. Multivariable linear regressions were run to test each visual measure with driving outcomes. The average age was 72.2 years, 57.3% were male, and 72.5% were White. There were significant associations for a one-point increase in visual field and quality of corrected vision (RR = 1.06; 95% CI = 1.03–1.10), day vision (RR = 1.05; 95% CI = 1.03–1.08), night vision (RR = 1.08; 95% CI = 1.05–1.13), visual acuity score and higher quality of corrected of vision (RR = .41; 95% CI = .22-.77), day vision (RR = .39; 95% CI=.22–.71), and night vision (RR = .41; 95% CI = .18–.94); visual acuity score and ability to drive safely compared to other drivers your age (RR = .53; 95% CI = .29–.96). Individuals with poorer visual acuity and visual fields rate their vision and ability to drive lower than those with better vision, and this information will allow clinicians to understand where to target interventions to enhance safe driving practices.

scholarly journals Unexpected Genetic Cause in Two Female Siblings with High Myopia and Reduced Visual Acuity

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
M. N. Preising ◽  
C. Friedburg ◽  
W. Bowl ◽  
B. Lorenz
Keyword(s):  
Visual Acuity ◽  
High Myopia ◽  
Autosomal Recessive ◽  
Electrical Coupling ◽  
Splice Site Mutation ◽  
Bipolar Cells ◽  
Night Vision ◽  
Site Mutation ◽  
Frequent Finding ◽  
Biallelic Mutations

In daily life, myopia is a frequent cause of reduced visual acuity (VA) due to missing or incomplete optical correction. While the genetic cause of high myopia itself is not well understood, a significant number of cases are secondary to hereditary malfunctions or degenerations of the retina. The mechanism by which this occurs remains yet unclear. Two female siblings, 4 y and 2 y, respectively, from a consanguineous Pakistani family were referred to our department for reduced VA and strabismus. Both girls were highly myopic and hence were further examined using standard clinical tests and electroretinography (ERG). The latter confirmed confounded electrical coupling of photoreceptors and bipolar cells. Further inquiry and testing confirmed a similar condition for the father including impaired night vision, reduced VA, photophobia, and an equally characteristic ERG. Findings in the mother were unremarkable. Subsequent genetic analysis of autosomal recessive and X-linked genes for congenital stationary night blindness (CSNB) revealed a novel homozygous splice site mutation in CACNA1F in the two girls transmitted from both the father and the mother. While in males the above clinical constellation is a frequent finding, this report, to the authors’ knowledge, is the first demonstrating biallelic mutations at the CACNA1F locus in females.

A Comparison of Visual Acuity Performance between a Binocular Night Vision Goggle and Two Types of Monocular Night Vision Goggles

1980 ◽  
Vol 24 (1) ◽  
pp. 306-309
Author(s):  
Robert M. Waters ◽  
Larry W. Avery
Keyword(s):  
Visual Acuity ◽  
Depth Perception ◽  
Low Cost ◽  
Light Level ◽  
Night Vision ◽  
Low Light ◽  
Light Intensification

Two experiments were run comparing the operational binoculars AN/PVS-5 Night Vision Goggles with two monocular low cost night vision goggles using newer light intensification techniques. No decrement in performance was noted in visual acuity or depth perception with the monocular low cost goggles; an improved capability was noted with the new goggles in low light level conditions.

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