Patent · US Expired

Automotive headlamp

US5067053A · kind A · utility

16Cited by
6References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 30, 1989
Grant dateNov 19, 1991
Priority date
Expiry dateNov 30, 2009

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF21S41/336
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a headlamp having a light-diverging concave mirror, the inner reflecting surface of the concave mirror is a composite paraboloidal surface of revolution made of multiple different paraboloidal surfaces of revolution taking as common focus a predetermined point on the optical axis and smoothly joined to each other, and the lamp bulb is so disposed as to have the center thereof disposed as substantially coincident with the common focus. Each of the different paraboloidal surfaces of revolution composing the inner reflecting surface reflects the rays incident from the lamp bulb in directions away from the optical axis in a horizontal plane in which the optical axis lies, in directions parallel to the optical axis or in directions nearer to the optical axis. Since the angles of the reflected rays with respect too the optical axis are different depending upon their distances from the common focus, the luminous intensity distribution pattern can have an ample amount of light and the pattern can be extended nearly uniformly from its center horizontally to the right and left, and also the light amount can be adjusted. Therefore, the rays emitted from the lamp bulb can be utilized most e…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.