Estimation of glare load from small illuminance peaks in real life driving situations

In several real life driving tests performed by the Laboratory of Lighting Technology at the TU Darmstadt, the illuminance caused at the driver’s eye by an oncoming vehicle was measured. The obtained data showed that due to road unevenness peaks of different intensity and duration can occur at the eye. In this research a laboratory study is performed to recreate these peaks for test subjects while measuring their pupil dilation as well as their glare load via de Boer rating. The test leads to a strong correlation between exposure and de Boer rating of the subject. The found model leads to a R² of 0.8 and better depending on the length and intensity of the peaks. This knowledge is then used in a real driving situation. These tests lead to the conclusion, that more research is needed to obtain glare data from real driving tests by simply measuring the pupil size of test subjects, but in general a correlation between different car states and pupil diameter is found.