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http://dx.doi.org/10.3807/JOSK.2016.20.5.586

A Luminance Compensation Method Using Optical Sensors with Optimized Memory Size for High Image Quality AMOLED Displays  

Oh, Kyonghwan (Department of Electronic Engineering, Hanyang University)
Hong, Seong-Kwan (Department of Electronic Engineering, Hanyang University)
Kwon, Oh-Kyong (Department of Electronic Engineering, Hanyang University)
Publication Information
Journal of the Optical Society of Korea / v.20, no.5, 2016 , pp. 586-592 More about this Journal
Abstract
This paper proposes a luminance compensation method using optical sensors to achieve high luminance uniformity of active matrix organic light-emitting diode (AMOLED) displays. The proposed method compensates for the non-uniformity of luminance by capturing the luminance of entire pixels and extracting the characteristic parameters. Data modulation using the extracted characteristic parameters is performed to improve luminance uniformity. In addition, memory size is optimized by selecting an optimal bit depth of the extracted characteristic parameters according to the trade-off between the required memory size and luminance uniformity. To verify the proposed compensation method with the optimized memory size, a 40-inch 1920×1080 AMOLED display with a target maximum luminance of 350 cd/m2 is used. The proposed compensation method considering a 4σ range of luminance reduces luminance error from ± 38.64%, ± 36.32%, and ± 43.12% to ± 2.68%, ± 2.64%, and ± 2.76% for red, green, and blue colors, respectively. The optimal bit depth of each characteristic parameter is 6-bit and the total required memory size to achieve high luminance uniformity is 74.6 Mbits.
Keywords
AMOLED displays; Luminance compensation; Optical sensors; Image quality;
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