Browse > Article
http://dx.doi.org/10.5573/ieie.2016.53.11.048

Monolithic Ambient-Light Sensor System on a Display Panel for Low Power Mobile Display  

Woo, Doo Hyung (School of Information, Communications & Electronic Engineering, The Catholic University of Korea)
Publication Information
Journal of the Institute of Electronics and Information Engineers / v.53, no.11, 2016 , pp. 48-55 More about this Journal
Abstract
Ambient-light sensor system, which changes the brightness of a display as ambient light change, was studied to reduce the power consumption of the mobile applications such as note PC, tablet PC and smart phone. The ambient-light sensor system should be integrated on a display panel to improve the complexity and cost of mobile applications, so the ambient-light sensor and readout circuit was integrated on a display panel using low-temperature poly-silicon thin film transistors (LTPS-TFT). We proposed the new compensation method to correct the panel-to-panel variation of the ambient-light sensors, without additional equipment. We designed and investigated the new readout circuit with the proposed compensation method and the analog-to-digital converter for the final digital output of ambient light. The readout circuit has very simple structure and control timing to be integrated with LTPS-TFT, and the input luminance ranges from 10 to 10,000 lux. The readout rate is 100 Hz, and maximum differential non-uniformity with 20 levels of the final output below 0.5 LSB.
Keywords
ambient light sensor system; readout circuit; non-uniformity correction; LTPS-TFT; mobile display;
Citations & Related Records
연도 인용수 순위
  • Reference
1 M. Karube, et al., "Low power consumption for circuits integration of low temperature poly-Si TFT-LCDs", IDW Digest, pp. 1229-1230, 2005.
2 T. Nishibe, and H. Nakamura, "Value-added circuit and function integration for SOG base on LTPS technology", SID symposium Digest, pp. 1091-1094, 2006.
3 J. F. Wu, et al., "Integrated ambient light sensor on a LED driver chip", IEEE PEDS Digest, pp. 944-947, 2011.
4 K. Maeda, et al., "The system-LCD with monolithic ambient-light sensor system", SID symposium Digest, pp. 356-359, 2005.
5 H. S. Park, T. J. Ha, Y. Hong, M. K. Han, D. H. Woo, K. S. Shin, and C. W. Kim, "A self -reset ambient-light sensor system for lowtemperature polycrystalline-silicon active-matrix displays", Journal of the SID, pp. 889-893, 2008.
6 D. Fish, et al., , "Improved optical feedback for AMOLED display differential ageing compensation", SID symposium Digest, pp. 1120-1123, 2004.
7 Y. Vygranenko, M. Fernandes, A. Sazonov, and M. Vieira, "Driving scheme using MIS photosensor for luminance control of AMOLED pixel", Journal of display technology, pp. 1-5, 2013.