Open AccessLuminance uniformity study of OLED lighting panels depending on OLED device structures
Author(s) -
Hyeong Woo Bae,
Young Hoon Son,
Beom-mo Kang,
Jung Min Lee,
Hyoungsik Nam,
Jang Hyuk Kwon
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.030701
Subject(s) - luminance , tandem , oled , materials science , optics , optoelectronics , voltage , physics , layer (electronics) , nanotechnology , composite material , quantum mechanics
This paper describes the luminance uniformity of OLED lighting panels depending on OLED device structures of single emission layer (single-EML), 2-tandem, and 3-tandem. The luminance distribution is evaluated through the circuit simulation and the fabricated panel measurement. In the simulation results with yellow-green color panels of 30 × 80 mm 2 emission area, a 3-tandem structure shows the lowest non-uniformity (1.34% at 7.5V), compared to single-EML (5.67% at 2.8V) and 2-tandem (2.78% at 5.3 V) structures at 1,000 cd/m 2 . The luminance non-uniformity is germane to the OLED conductance showing that the high luminance-current efficiency is of the most importance to achieve the uniform voltage and luminance distribution. In measurement, a 3-tandem structure also achieves the most uniform luminance distribution with non-uniformity of 4.1% while single EML and 2-tandem structures accomplish 9.6%, and 6.4%, respectively, at ~1,000 cd/m 2 . In addition, the simulation results ensure that a 3-tandem structure panel is allowed to be enlarged the panel size up to about 5,000 mm 2 for lower luminance non-uniformity than 10% without any auxiliary metal electrodes.