Extraction and evaluation of mura images in liquid crystal displays

Y. Mori, K. Tanahashi, R. Yoshitake, S. Tsuji


11 被引用数 (Scopus)


The visual performance of liquid crystal displays (LCDs) has usually been evaluated by visual inspection during the manufacturing process. One of the visual problems hardest to recognize are regions of low-contrast and non-uniform brightness called muras. The accurate and consistent detection of the muras is extremely difficult because there are various shapes and sizes of muras and the inspection results tend to depend on the operators. We conducted a study on the quantitative evaluation of muras based on visual analysis, intending to clarify the detection method and create an automated mura inspection process. We developed an algorithm and a hardware system based on a commercially available CCD camera and a PC with an image processor board. This system can successfully identify and evaluate muras. The algorithm was developed from research on visual analysis and human perception. We converted the front-of-screen (FOS) images from the LCDs into distributions of luminance information, and the mura regions were distinguished from the background area using our novel algorithm. This approach also led to a weighting function for the categories of muras that appear in the panels. Our identification method can also distinguish between the muras caused by flaws in the LCD cells and the intentionally designed non-uniform luminance distribution of the backlight.

ジャーナルProceedings of SPIE - The International Society for Optical Engineering
出版ステータスPublished - 2001 12月 1
イベントAlgorithms and Systems for Optical Information Processing - San Diego, CA, United States
継続期間: 2001 7月 312001 8月 2

ASJC Scopus subject areas

  • 電子材料、光学材料、および磁性材料
  • 凝縮系物理学
  • コンピュータ サイエンスの応用
  • 応用数学
  • 電子工学および電気工学


「Extraction and evaluation of mura images in liquid crystal displays」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。