Spectacles for reducing glare due to oncoming traffic while driving at
night. The spectacles include a mask or filter that blocks light from
entering the wearer's eyes when the source of light is on the opposing
side of the highway. The mask may either be a part of the lenses of the
spectacles or supported in front of the spectacle lenses by means of a
"clip-on" device. If a perpendicular reference line is drawn on the
lenses that passes through the optical center of the lens, the mask
covers the portion of the lens between .about.225.degree. and 15.degree.
with respect to the perpendicular (or the mirror image on British-type
highways), or, with reference to the face of a clock, the portion of the
lens between 7:30 and 12:30. The mask can be opaque, or it can be a low
transmissivity filter (transmissivity .about.10%) or a notch filter that
passes only red light. The angle from which oncoming light can be blocked
my be changed by a slight rotation of the wearer's head.