contrast

The contrast denotes the difference between the brightness or color between different illuminated elements in a room or a surface.
Lighting with high contrast creates a clear distinction between light and dark areas, while lighting with low contrast creates a flatter, less distinctive representation.
Contrast can create visual effects to draw attention to certain areas or to influence the mood of a room.
A reasonable contrast is also important for visual comfort, since insufficient lighting or too high contrasting can lead to too much strain on the eyes or glare.