Glare is regarded as a sensation produced by light which enters the eye in such a fashion as to inhibit distinct vision. When this light is superimposed upon a retinal image, glare reduces contrast and is called veiling glare. When luminance levels are very high, glare may have dazzling effects (dazzling glare), and when intense directed light reduces the sensitivity of the retina in part or as a whole, blinding or scotomatic glare is experienced.1 The visibility of objects is reduced in the presence of glare, particularly in the vicinity of a blinding glare source. To overcome the loss in visibility the contrast between figure and ground must be enhanced, or the size of the object seen must be increased.2-4 Under conditions of glare the pupil of the eye responds to the high luminance with a constriction and thus reduces the radiant flux reaching the retina.5,6 The