When you look around a room, you should feel no strain on your eyes, the need to squint or to gaze away. Visual comfort is the balance between the intensity of the light, the colors of the light, and the horizontal and the vertical illuminance of table tops, floors and walls. The opposite of visual comfort is glare. You experience the uncomfortable sensation of glare when looking at very bright surfaces set against dark backgrounds. Glare is all about contrast; the brighter the surface and the darker the background, the more uncomfortable you will find the glare. For example, imagine driving at night looking into the high beams of an approaching vehicle. Behind those lights there is only darkness. Surely, you will avoid looking right into the headlights and gaze away to avoid the discomfort. During the day, the headlights are surrounded by daylight, so there is no contrast, no glare and no visual discomfort.
To avoid glare in a room, you should opt for fixtures that have good optics to protect the eye from the light source
This kind of glare is unfortunately also common in indoor environments. For example, a badly designed fixture with unsatisfactory louvers can leave the naked light source exposed to the eye from different angles. Glare can also occur when the contrasts between the horizontal and vertical surfaces are too sharp. In a workplace environment, glare can quickly become a problem, resulting in fatigue, headaches and concentration difficulties. To avoid glare in a room, you should opt for fixtures that have good optics to protect the eye from direct exposure to the light source. In addition, good optics help uniformly distribute the light to a room’s different surfaces, softening the contrasts. Another great way to create visual comfort in a room is to compliment the illuminated spaces with some special-purpose fixtures designed to cast light on the walls.