tailieunhanh - ZnO nanoparticles in bettering the color uniformity of phosphor-converted white led lights

Managing the color uniformity of WLEDs means controlling the size and concentration of ZnO. With the concentration of 10% ZnO, the lumen output of LEDs reaches the highest values. Meanwhile, when the concentration and size of ZnO are 14% and 500 nm respectively, ∆CCT is reduced to the lowest value. Based on the manufacturers' requirements, the most appropriate ZnO concentration and particle size can be determined. However, if requirements include both lumen and color uniformity, the right choice is 14% concentration with 500 nm particle size of ZnO. | VOLUME 4 ISSUE 3 2020 September ZnO Nanoparticles in Bettering The Color Uniformity of Phosphor-Converted White Led Lights 1 2 3 Ming-Jui CHEN Van Tho LE Doan Quoc Anh NGUYEN 3 Thinh Cong TRAN 1 Department of Electrical Engineering National Kaohsiung University of Science and Technology Kaohsiung Taiwan 2 Institute of Tropical Biology Vietnam Academy of Science and Technology Ho Chi Minh City Vietnam 3 Faculty of Electrical and Electronics Engineering Ton Duc Thang University Ho Chi Minh City Vietnam Corresponding Author Doan Quoc Anh NGUYEN Email nguyendoanquocanh@ Received 14-Feb-2020 accepted 20-Jun-2020 published 30-Sep-2020 DOI http Abstract. To make further improvements in most appropriate ZnO concentration and parti- future WLED generation bettering color unifor- cle size can be determined. However if require- mity is an important goal manufacturers desire ments include both lumen and color uniformity to accomplish. One of the most common and ef- the right choice is 14 concentration with 500 fective methods to enhance the color homogene- nm particle size of ZnO. ity is the one focusing on improving scattering in phosphor layer which can be achieved by adding ZnO into the phosphor layer. Based on theoret- Keywords ical application of Mie-scattering we compute and analyze the scattering characteristics of the WLEDs Mie-scattering theory remote di usor particles. From the results the ZnO phosphor package color rendering index particles are proven to have positive in uences lumen output. on the development of lighting quality. Addition- ally the article analyzed and presented the ef- fects of ZnO concentration which uctuates from 2 to 22 on the color homogeneity. Thus the color uniformity is in uenced not only by the 1. Introduction particle size but also by the concentration of the added ZnO. Hence managing the color unifor- Light-emitting diodes LEDs have many bene- mity of WLEDs means controlling the size and ts