Ching-Cherng SUN^*, Chong-Jhih JIANG, Yi-Chun CHEN, and Tsung-Hsun YANG

Department of Optics and Photonics, Institute of Lighting and Display Science, National Central University, Chungli 320, Taiwan

(Received October 9, 2013; Accepted February 18, 2014)

This study is aimed to assess the glare effect from LED-based street lamps with three general optical designs, which are cluster LEDs with a single lens, a LED array accompany with a lens array, and a tilted LED array, respectively. Observation conditions were simulated based on various locations and viewing axes. Equivalent luminance calculations were used to reveal the glare levels of the three designs. The age effect for the calculated equivalent luminance was also examined for human eyes of people at the age of 40 or 60. The results demonstrate that among the three design types, a LED array accompany with a lens array causes relatively smaller glare for most viewing conditions.

Key words: LED-based street lamps, LED arrays, direct luminance, veiling luminance

^*E-mail address: ccsun@dop.ncu.edu.tw