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Updated: Mar 13, 2026
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Assessing Binocular Central Visual Field and Binocular Eye Movements in a Dichoptic Viewing Condition
Published on: July 21, 2020
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[Contrast vision-definitions, conversions, and equivalence tables]
M Bach1,2, M B Hoffmann3,4, H Jägle5
1Klinik für Augenheilkunde, Universitätsklinikum Freiburg, Killianstr. 5, 79106, Freiburg, Deutschland. michael.bach@uni-freiburg.de.
Summary
Understanding human contrast vision is crucial, but definitions vary. This study clarifies five key contrast vision measures (Michelson, Weber, contrast ratios, logCS) and provides conversion formulas, recommending logCS for clarity.
Area of Science:
- Ophthalmology
- Visual Science
- Optometry
Background:
- Quantitative assessment of human contrast vision is increasingly important.
- Existing literature presents confusing, differing definitions and quantification methods for contrast vision.
- Variations in contrast ratio definitions, such as reciprocal values in Germany, highlight the need for standardization.
Purpose of the Study:
- To present and clarify the five most significant definitions of luminance contrast and contrast vision.
- To provide a unified framework for understanding and converting between different contrast metrics.
- To recommend a standardized unit for contrast vision assessment.
Main Methods:
- Review and synthesis of five key definitions: Michelson contrast, Weber contrast, contrast ratios, and logCS (luminance contrast sensitivity).
- Development of formulae for converting between all presented contrast metrics.
- Creation of a table detailing equivalent values across different definitions.
Main Results:
- Detailed explanation of the five primary contrast vision definitions and their specific application domains.
- Provision of accurate conversion formulas enabling seamless transition between metrics.
- A comprehensive table of equivalent values for practical reference.
Conclusions:
- The study clarifies prevalent, yet often confusing, definitions of contrast vision.
- Standardized conversion formulas and equivalent values facilitate consistent quantitative assessment.
- The logCS unit is recommended for its clarity and utility in assessing contrast vision.
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