| | NHTSA Notice: Glare from Headlamps and other Front Mounted Lamps - FMVSS 108 (Site not responding. Last check: 2007-11-05) |
 | | Glare associated with daytime running lamps is the subject of an ongoing rulemaking intended to reduce their intensity (see 63 FR 42348, Docket NHTSA-98-4124 Notice 1.) This notice does not address daytime running lamps; it does address headlamps and other front-of-vehicle roadway illumination lamps that are used primarily at night. |
 | | For example, there were many variants of glare reducing devices, before lower and upper beams became the norm, that were achieved by a mechanical metal shield that was rotated into place in front of the bulb within the headlamp, typically by using a driver actuated cable. |
 | | The oncoming drivers experience transient glare because of the rate of closure speed, the quickly widening angle from the observer to the glare source, and the transient nature of hills and curves. |
| www.nhtsa.gov /cars/rules/rulings/glare.html (15122 words) |