Premium
Gradient refractive index structure of phosphor‐in‐glass coating for packaging of white LED s
Author(s) -
Xu Xujia,
Li Hong,
Zhuo Yong,
Xiong Dehua,
Chen Mingxiang
Publication year - 2019
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/jace.16031
Subject(s) - phosphor , refractive index , materials science , coating , luminous efficacy , high refractive index polymer , substrate (aquarium) , light emitting diode , composite material , optics , screen printing , optoelectronics , layer (electronics) , oceanography , physics , geology
A gradient refractive index ( GRIN ) structure, with a gradual increase in the refractive index from the glass substrate, was successfully obtained by multilayer screen printing for white light‐emitting diodes (w‐ LED s) packaging. Each phosphor‐in‐glass (PiG) coating consisted of B 2 O 3 –SiO 2 –ZnO glass matrix and yellow phosphor. The gradually increased refractive index (1.62, 1.72, and 1.82) of glass matrices were obtained from higher molecular weight of La 2 O 3 and WO 3. After sintering at 600°C, no obvious interface was observed and the phosphor particles were mixed thoroughly in the glass matrix. When the phosphor content was 50 wt%, the white‐light emission was obtained. Compared with those based on the nongradient and low‐refractive PiG coating, the luminous efficacy of w‐ LED s constructed by the PiG coating with GRIN was enhanced. It shows that the GRIN structure is beneficial to improve the luminous efficacy of w‐ LED s.