Highway tests of photochromic lenses.

A highway study of clear, tinted and photochromic prescription spectacles was conducted using a 58-mile driving course marked with 130 randomly spaced transverse white stripes. The data of 29 subjects totaling more than 21,000 stripe detection events showed that coated photochromic prescription lenses performed better by day and poorer by night compared to uncoated white crown prescription lenses, and that a multiple-layer coated, tinted lens (Neo Multicoat) performed at least as well, day or night, as did the uncoated white crown lens.