The luminance of pure black: exploring the effect of surround in the context of electronic displays

The overall image quality benefits substantially from good reproduction of black tones. Modern displays feature relatively low black level, making them capable rendering good dark tones. However, it is not clear if the black level of those displays is sufficient to produce a “absolute black” color, which appears no brighter than an arbitrary dark surface. To find the luminance necessary to invoke the perception of the absolutely black color, we conduct an experiment in which we measure the highest luminance that cannot be discriminated from the lowest luminance achievable in our laboratory conditions (0.003 cd/m). We measure these thresholds under varying luminance of surround (up to 900 cd/m), which simulates a range ambient illumination conditions. We also analyze our results in the context of actual display devices. We conclude that the black level of the LCD display with no backlight dimming is not only insufficient for producing absolute black color, but it may also appear grayish under low ambient light levels.