| Title |
A study on 5000 K LED Module Satisfying Installation Criteria of S1 or P1 Class with High Color Rendering Properties |
| Authors |
Jong-Oh Kim ; Hyeong-Seob Jo ; Uh-Chan Ryu |
| DOI |
http://doi.org/10.5207/JIEIE.2020.34.10.001 |
| Keywords |
LED lighting; S/P ratio; CRI; Mesopic vision; Pupil lumen |
| Abstract |
For outdoor lighting products, important decision factors were luminous efficacy, luminance, and scotopic/photpic (S/P) ratio. Recently interest in amenity facilities for road safety and urban aesthetic conditions at night time has increased. Therefore high color rendering properties, such as color rendering index (CRI), color fidelity (Rf), color gamut (Rg), and color quality scale (Qa) have also been considered for outdoor lighting products. In the previous studies, S/P ratio and CRI are in a trade-off relationship and can be improved simultaneously to a certain level by mixing 455-nm blue LED and 2～7 types of phosphors in simulation method. In this paper, based on the previous simulation results, an LED module of correlated color temperature (CCT) 5,000 K was fabricated with LED packages produced by mixing a 455-nm blue LED and two types of phosphors. As a result, S/P ratio≥2.22, with Ra≥96, R9∼14≥94, Rf≥90, Rg≥99, and Qa≥95 could be achieved at the same time and pupil lumens were calculated to be improved by 10 % compared to the conditions of the BS 5489-1 standard. |