Discomfort Glare from a Cyclic Source in Outdoor Lighting Conditions

ABSTRACT

Many models of discomfort glare have been proposed for outdoor lighting applications. Most of them were built from data collected in the laboratory in static situations, with motionless light sources, which main characteristics (luminance, size and position) were constant over time. However, on the road at night, drivers are moving with multiple sources around them. To fill the gap between static situations and more realistic ones, four psychophysic experiments were carried out in a laboratory to investigate the impact of the cyclic variations of several light source characteristics (its luminance, eccentricity and solid angle) on the discomfort glare. The temporal frequencies have been chosen representative of outdoor lighting conditions, up to 2.6 Hz. No impact of the dynamics of the glare source was found, except for a source with variable luminance at a low frequency ($f=0.65Hz$).

KEYWORDS:

• Discomfort glare
• LED
• psychophysics
• road lighting
• automotive lighting

Acknowledgments

The authors would like to thank the technical team for its help in the development of the experimental devices, and all the participants who took part in the experiments.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1. https://www.marketsandmarkets.com/Market-Reports/outdoor-led-lighting-market-211822268.html.

2. In most indoor lighting models, the Guth position index is preferred instead of ${\theta }_S$.

3. For instance, when the participant clicked the right button for trial number $i$, and then clicked the left button for trial number $i+1$.

4. The panel was composed of 34 participants (14 women and 20 men), between 20 and 63 years old (M = 35.1 / $\sigma$=12.3).

5. The panel was composed of 31 participants (13 women and 18 men), between 21 and 57 years old (M = 33.4 / $\sigma$=10.3).

6. The panel was composed of 33 participants (15 women and 18 men), between 21 and 57 years old (M = 33.7 / $\sigma =10.5$).

7. For this study, seven outliers have been rejected. The final panel was composed of 33 participants (15 women and 18 men), between 21 and 57 years old (M = 33.7 / $\sigma =10.5$).

Additional information

Funding

The authors report no funding.