Model predicting discomfort glare caused by LED road lights

Area of Science:

• Lighting Engineering
• Human Factors and Ergonomics
• Vision Science

Background:

• Discomfort glare from LED road lighting is a growing concern.
• Existing models may not fully capture LED-specific glare characteristics.
• Quantifying glare perception is crucial for driver comfort and safety.

Purpose of the Study:

• To develop and validate a model for predicting discomfort glare from LED road lighting.
• To investigate the influence of key visual parameters on perceived glare.
• To compare LED glare characteristics with traditional lighting sources.

Main Methods:

• Simulated 72 distinct light conditions varying average glare source luminance (Lg), background luminance (Lb), solid angle (ω), and viewing angle (θ).
• Collected participant ratings of perceived discomfort glare using the deBoer scale.
• Developed a predictive model based on significant variables and interactions.
• Validated the model through laboratory and real-world road conditions.

Main Results:

• All four investigated variables (Lg, Lb, ω, θ) and their interactions significantly impacted perceived glare.
• The developed model demonstrated high predictive accuracy, with a correlation of 0.87 between measured and predicted values.
• Residual deviation was approximately 1 unit on the deBoer rating scale, indicating good model fit.

Conclusions:

• The study successfully developed a validated model for estimating discomfort glare in LED road lighting.
• The findings provide a quantitative understanding of factors influencing LED glare perception.
• The model aids in designing more comfortable and safer road lighting environments, clarifying LED vs. traditional source glare differences.