Single-mode vehicular headlamp system

Abstract

A single pair of headlamps that each contain a single on-focus light source and produce different but complementary beam patterns are mounted on a motor vehicle to provide a composite beam of intense non-glare light that is used for city, rural and turnpike driving and thus remains 'fixed' and constant for all driving conditions. The use of a single light source in each headlamp improves the optical efficiency of the lighting system and provides both long range and short range illumination of the roadway with a minimum amount of energy and drain on the electrical system of the vehicle. The headlamps are not interchangeable and must be mounted in proper relationship on the vehicle to provide the single-mode illumination. However, they can be of circular or rectangular shape and have reflector and lens components that are preferably hermetically sealed to one another to provide sealed-beam type lamps, or which can be separated and thus form housings that can be opened to permit the light sources to be removed and replaced. When the headlamps are of sealed-beam construction, a coiled wire filament or a compact halogen-cycle type incandescent lamp can be used as the light source. Standard compact incandescent lamps or halogen-cycle incandescent lamps are employed in headlamps that are not hermetically sealed. Reflector components of dual-segment construction can also be used to obtain beam patterns having the proper characteristics.