On-site road properties evaluation for dry and wet asphalt roads using an imaging luminance measurement device

A method was developed to investigate the reflected properties of LED and HPSlighted wet roads using on-site measurement of luminance images. An ILMD was used to obtain high observation angles by placing it at a close distance to the ROI. The luminance images were analyzed to derive a distribution of reflected luminance as a function of deviation, incidence, and observation angles. Furthermore, an investigation of the reflected characteristics of a dry asphalt road illuminated by LED lighting was conducted, employing on-site measurements of the images of luminance and the distribution of illuminance. The results provide valuable insights for designing lighting systems and mitigating the adverse effects of glare and specular reflection on road safety.