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

다국어 초록 (Multilingual Abstract)

This paper proposes a luminance compensation method using optical sensors to achieve high luminanceuniformity of active matrix organic light-emitting diode (AMOLED) displays. The proposed methodcompensates for the non-uniformity of luminance by capturing the luminance of entire pixels and extractingthe characteristic parameters. Data modulation using the extracted characteristic parameters is performedto improve luminance uniformity. In addition, memory size is optimized by selecting an optimal bit depthof the extracted characteristic parameters according to the trade-off between the required memory size andluminance uniformity. To verify the proposed compensation method with the optimized memory size, a40-inch 1920×1080 AMOLED display with a target maximum luminance of 350 cd/m2is used. Theproposed 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 memorysize to achieve high luminance uniformity is 74.6 Mbits.

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