Our visual system is basically designed for very different brightness levels in a very wide dynamic range.
Some visual tasks, especially in the working world, such as reading a display in the immediate vicinity of a window, looking at a screen with the reflection of a skylight, ... can nevertheless lead to an excessive demand on our visual perception ability if the luminance levels or luminance differences in the visual field are too great.
It is worth noting that our tolerance for high luminance differences is greater in daylight than in artificial lighting. It does not make sense to apply the usual glare ratings for artificial lighting solutions to daylight situations, because the “glare source“ of daylight is dynamic in terms of its location and intensity. This enlivens an interior situation and reduces the potential for disturbance.
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