THERE can be no doubt that automobile travel at night is dangerous when the driver wears colored glasses.1 There has been, however, no agreement about how much of any color, or what combinations of color, can be considered safe for general public use in glasses and windshields. The tinted glass used is not dark enough to change the color of traffic signals significantly, although there have been complaints about low brightness and poor color rendition of outdoor drive-in movies. The chief objection to the use of tinted glass is the possibility of accident due to reduced visual efficiency at night.
Particularly unfortunate is the popular selection of pink for the glasses and aquamarine green for the windshields. While pure red and pure green filters may be quite transparent, in combination they are opaque. How much loss of vision at night might be expected from pink glasses and green windshields?