← Back to Patent Explorer
US5014166A Expired / Lapsed US ⏱️ 0.0 years remaining

Light unit

Assignee: Magneti Marelli UK Ltd
•
Filing: 1989-10-10
•
Granted: 1991-05-07
•
Expires: 2009-10-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A motor vehicle headlamp comprising a dished body having an ellipsoidal inner reflective surface. A lamp filament is disposed at an inner focal point of the surface. A diverging meniscus lens element having a smooth convex rear surface is disposed between the reflective surface and a front cover. The lens element has a smooth concave outer surface, although the latter may be a concave fresnel lens. The convex rear surface of the lens element reduces the risk of unwanted light scatter compared with the use of a concave rear surface.

Inventors

  • 👤 Geoffrey Draper
  • 👤 Hayden James
  • 👤 Kevin Carlton

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 05:18
CPC Classifications
F; F21; F21S; F21S41/00; F21S41/20; F21S41/28

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 95 words
A motor vehicle headlamp comprising a dished reflector body having means defining a front opening; an internal reflective surface in said body, said reflective surface being ellipsoidal with inner and outer focal points and a major axis extending through said front opening so that the outer focal point is disposed externally of said dished reflector body; and a correcting lens system extending transversely of said dished reflector body between said inner and outer focal points, said correcting lens system having the properties of a divergent meniscus lens whose convex surface faces said inner focal point.
Claim 2
Dependent Claim 95 words
A motor vehicle headlamp comprising a dished reflector body having means defining a front opening; an internal reflective surface in said body, said reflective surface being ellipsoidal with inner and outer focal points and a major axis extending through said front opening so that the outer focal point is disposed externally of said dished reflector body; and a correcting lens system extending transversely of said dished reflector body between said inner and outer focal points, said correcting lens system having the properties of a divergent meniscus lens whose convex surface faces said inner focal point.
Claim 3
Dependent Claim 83 words
The headlamp according to claim 1, wherein said dished reflector body has a rear aperture for receiving a lamp including a filament providing a light source, and means are provided for retaining said lamp in said body with said filament disposed at said inner focal point; and wherein said correcting lens system is arranged relative to said inner focal point so that none of the reflected light from said reflective surface crosses the major axis of the ellipse before reaching said lens system.
Claim 4
Dependent Claim 27 words
The headlamp according to claim 2, wherein said retaining means is arranged to retain said filament so that the centre thereof is on said inner focal point.
Claim 5
Dependent Claim 20 words
The headlamp according to claim 1, wherein the convex rear surface of said lens system is a smooth convex surface.
Claim 6
Dependent Claim 19 words
The headlamp according to claim 1, wherein a front surface of the lens system is a smooth concave surface.
Claim 7
Dependent Claim 19 words
The headlamp according to claim 1, wherein a front surface of the lens system is a concave fresnel lens.
Claim 8
Dependent Claim 23 words
A headlamp as claimed in claim 1 wherein the lens system is provided by a single lens element having said convex rear surface.

References Cited (Backward Citations)

US1571139A Cited
US4577260A Cited
US4811174A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-05-06 1994-11-05 1995-05-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-05-06 1998-11-05 1999-05-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-05-06 2002-11-05 2003-05-07 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag