Color-Tunable White LEDs with Single Chip Realized through Phosphor Pattern and Thermal-Modulating Optical Film

Micromachines

Zhenpeng Su¹  Huai Zheng¹  Yang Peng²  SangWoo Joo³  Fan Bai³  Zheng Gong⁴  Bo Zhao⁴ 

[1] Institute of Technological Sciences, Wuhan University, Wuhan 430072, China;School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan 430074, China;School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749, Korea;School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China;

关键词: light-emitting diodes (LEDs);    correlated color temperature (CCT);    LED packaging;    paraffin-PDMS film;   

DOI  :  10.3390/mi12040421

来源: DOAJ

【 摘 要 】

In this paper, a new method to regulate the correlated color temperature (CCT) of white light-emitting diodes (LEDs) is proposed for the single-chip packaging structure, in which the blue light distribution emitted from the chip in the red/yellow phosphor layer was modulated through changing the paraffin-polydimethylsiloxane (PDMS) film transparence and haze. The results show that the transmittance of the paraffin-PDMS film can be modulated from 49.76% to 97.64%, while the haze of that ranges from 88.19% to 63.10%. When the thickness of paraffin-PDMS film is 0.6 mm, and the paraffin-PDMS film concentration is 30 wt%, the CCT of white LED decreases from 15177 K to 3615 K with the increase of thermal load in the paraffin-PDMS film. The modulating range of its CCT reaches 11562 K. The maximum CCT variation at the same test condition is only 536 K in the repeated experiments within one week.

【 授权许可】

Unknown