Why green can feel visually gentle
In daylight, the eye is especially sensitive to light around the green part of the spectrum. That means a green surface can look bright and distinct without needing as much light as a less-sensitive color would. When its brightness is moderate and its contrast is comfortable, the result may feel clear rather than glaring.
This is a property of how the visual system responds to light—not a special soothing effect of green. A vivid green screen at high brightness can still feel harsh, while a muted red or blue scene may be perfectly comfortable.
What makes a scene tiring
Eye comfort depends on more than hue. Strong glare, sharp contrast, small details, and long periods of close focus can all make viewing feel demanding. Staring also tends to reduce blinking, which can leave the eyes feeling dry or strained. Changing the brightness, increasing text size, or looking away regularly may help more than switching to a particular color.
Green can nevertheless be an easy color to gaze at when it forms a calm, evenly lit scene with enough contrast to see its details. The useful distinction is that green may make a visual signal feel clear without making it inherently restful: the light level and viewing conditions determine whether that clarity is comfortable.
