The effect of veiling luminance on the disability glare of car headlamps designed in Iran

ABSTRACT

Objectives. One of the main risk factors involved in increasing driving accidents at night is due to the veiling luminance of the car’s headlights reducing the contrast of images in the retina and, thus, reducing the visual performance of drivers. The aim of this study is to investigate the veiling luminance caused by the headlights of the best-selling vehicles in Iran. Methods. Using the Stiles–Holiday disability glare equation, the veiling luminance of headlights of common vehicles at distances of 10–100 m for both high-beam and low-beam modes of oncoming vehicles was measured on a road for healthy (young, middle-aged and older) drivers. Results. Under high-beam illumination, as the cars approached each other, the average illuminance of the car headlights gradually increased. Moreover, age had a significant impact on the veiling luminance. This study also showed that, in same-age groups, the Samand Souren and Peugeot Pars cars had the highest and lowest mean veiling luminance, respectively. Conclusion. The findings showed that the illuminance (at large distances between two cars) and the angle between the source of glare and the eyes of drivers (as two cars approach to each other) have a dominant influence on the disability glare.

KEYWORDS:

• disability glare
• veiling luminance
• car
• traffic accidents
• illuminance
• visual performance

Acknowledgements

A.M. and J.S. contributed equally to this work. The authors are grateful for financial support provided by Neyshabur University of Medical Sciences.

Disclosure statement

No potential conflict of interest was reported by the authors.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This study was supported by Neyshabur University of Medical Sciences [grant number: 96226].