Effect of Using High Signal-to-Noise Image Intensifier Tubes on Night Vision Goggle (NVG) Aided Visual Acuity

Abstract : A night vision goggle (NVG) image intensifier (I2) tube's signal-to-noise ratio (SNR) determines the low-light resolution capability, therefore, the higher the SNR, the better the ability of the tube to resolve objects under low illumination conditions. Two NVG models were used to determine if visual performance would improve as a result of a goggle's higher SNR characteristic. The F4949G-TG goggles, equipped with 12 tubes utilizing thin-filmed technology allowing for a higher SNR, and the F4949G goggles were tested. Twelve participants tested each goggle under six illumination and contrast conditions using an automated Landolt C visual acuity task. The results indicated statistically significant, although small, visual acuity differences between the two NVG models. Visual acuity scores obtained with the F4949G-TG model were better than those obtained with the F4949G at all illumination and contrast conditions examined, indicating an increase in the signal-to-noise ratio did contribute to the differences in visual performance.

[1]  Marinica Mirzu.  Design of an objective for night vision applications taking in account the signal-to-noise ratio criteria , 1999, Photonics Prague.

[2]  Chris Johnson.  The Operational Strengths and Weaknesses of Military Night Vision Equipment , 2004 .

[3]  James D. Whiteley,et al.  The Effect of Signal-to-Noise Ratio on Visual Acuity Through Night Vision Goggles , 1991 .

[4]  J T Holladay,et al.  Proper method for calculating average visual acuity. , 1997, Journal of refractive surgery.

[5]  Chris W. Johnson.  The Role of Night Vision Equipment in Military Incidents and Accidents , 2004, Human Error, Safety and Systems Development.

[6]  J. Bruce Baldwin,et al.  Aircrew visual acuity viewing with different night vision goggle eyepiece diopter settings , 2004, SPIE Defense + Commercial Sensing.

[7]  Joseph C. Antonio,et al.  Night Vision Goggle Model F4949 Preflight Adjustment/Assessment Procedures , 1993 .

[8]  I L Bailey,et al.  New Design Principles for Visual Acuity Letter Charts* , 1976, American journal of optometry and physiological optics.

[9]  H. L. Task.  Cockpit/NVG Visual Integration Issues , 1992 .

[10]  R. Helmreich.  On error management: lessons from aviation , 2000, BMJ : British Medical Journal.

[11]  M. Bach,et al.  The Freiburg Visual Acuity test--automatic measurement of visual acuity. , 1996, Optometry and vision science : official publication of the American Academy of Optometry.

[12]  Ian J. Murray,et al.  RETINAL ADAPTATION UNDER NIGHT-TIME DRIVING CONDITIONS , 1999 .

[13]  W C Gibson.  NIGHT VISION GOGGLE TRAINING AND THE WHEELED VEHICLE OPERATOR , 1990 .

[14]  G. E. Kline,et al.  Performance of Young and Older Drivers on a Static Acuity Test under Photopic and Mesopic Luminance Conditions , 1990, Human factors.

[15]  I L Bailey,et al.  Repeatability of Visual Acuity Measurement , 1998, Optometry and vision science : official publication of the American Academy of Optometry.

[16]  Clarence E. Rash,et al.  Visual Acuity with AN/PVS-5A Night Vision Goggles and Simulated Flashblindness Protective Lenses under Varying Levels of Brightness and Contrast , 1989 .

[17]  J E Sheedy,et al.  Visual Acuity and Chart Luminance , 1984, American journal of optometry and physiological optics.

[18]  Randall W. Gibb,et al.  Effect of Incompatible Light on Modified Class B Night Vision Goggle-Aided Visual Acuity and Contrast Sensitivity. , 1997 .

[19]  O. W. Richards.  Effects of Luminance and Contrast on Visual Acuity, Ages 16 to 90 Years , 1977, American journal of optometry and physiological optics.

[20]  Alex Pentland,et al.  Microcomputer-based estimation of psychophysical thresholds: The Best PEST , 1982 .