画像の平均輝度レベル，観視者の年齢，照明環境を考慮した液晶ディスプレイの輝度制御

摘要

We investigated what influences the average luminance level (ALL) of displayed images, screen illuminance, and viewers ages had on the preferred luminance of LCDs. Twenty young subjects (mean age: 21.8) and 24 seniors (mean age: 68.9) adjusted the luminance of a 17-inch 1000: 1 LCD monitor to their preferred levels under different experimental conditions. The results indicate that the preferred luminance of LCDs corresponded to the following formula: Lp=k×ALL~α. This is where Lp is the peak white luminance of the LCDs, k is a constant, and ALL is the average luminance level of the displayed images. Here, α is a constant from - 0.19 to - 0.20 for the seniors and from -0.14 to -0.17 for the young subjects. The influences of age-related changes in vision and ambient lighting on the luminance requirements for LCDs are also discussed. These results can be applied to the design of luminance-control systems for LCDs.%液晶ディスプレイ（LCD）は，表示する画像の平均輝度レベル（Average Luminance Level: ALL）によってバックライトの調光などの輝度制御をしない限り，ピーク自輝度がALLに依存せず一定となる．そのために，ALLが高い映像でまぶしさを感じやすい．この間題はALLが高い映像で輝度が低下するプラズマディスプレイ（PDP）との差異として指摘されてきた．