Discomfort glare is the visual discomfort experienced when individuals are exposed to light sources or luminaires that have a higher luminance than their eyes can adapt to. This type of glare can cause immediate discomfort or become apparent over time. Several factors influence the degree of discomfort glare, including the luminance and size of the glare source, the background luminance against which the glare source is viewed, and the position of the glare source in relation to the line of sight.