Quantitative Analysis of Contrast Sensitivity to Improve Visual Acuity and Reduce Optical Aberrations

Document Type : Original Article (s)

Authors

1 MSc Student, Department of Biomedical Engineering, School of Advanced Medical Technology, Isfahan University of Medical Sciences, Isfahan, Iran

2 Professor, Department of Biomedical Engineering, School of Advanced Medical Technology AND Medical Image and Signal Processing Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

3 Assistant Professor, Department of Biomedical Engineering, School of Advanced Medical Technology AND Medical Image and Signal Processing Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

4 Iranian Scientific Association of Optometry, Tehran, Iran

Abstract

Background: Human visual perception in detection of an object from background is based on edge emission and contrast. The optical aberration is the main factor to degrade quality of image in the eye. People with this complication perceive images with low levels of contrast and distorted edges. Since the conventional methods are cumbersome, the new complementary method such as Pre-compensation is offered for display devices. In this research we investigate quantitative effect of the contrast between the object and the background to reduce the effect of low order optical aberration by increasing regional contrast. We tried to find out which contrast level could improve visual acuity in Weber-contrast.Methods: In this Research, 12 optical charts with different levels of contrast were designed based on the log MAR standard. Then obtained patterns were tested on 20 patients with low order optical aberrations. The results of each chart were analyzed using SPSS software.Findings: There was a significant difference in visual acuity of persons at different contrast levels. But, when the Weber contrast percent was low, the difference was not remarkable.Conclusion: Based on the obtained results, a background with lower contrast improves visual acuity approximately up to 11% in the log MAR scale. Therefore, to improve visual acuity in display devices, foreground is more appropriate that be in higher state of brightness than background.

Keywords

References

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Journal of Isfahan Medical School
Volume 34, Issue 391 - Serial Number 391
May and June 2016
Pages 817-822

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History

  • Receive Date: 09 December 2015
  • Revise Date: 01 November 2024
  • Accept Date: 06 April 2022

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