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US4384271A Expired / Lapsed US ⏱️ 0.0 years remaining

Traffic light

Assignee: US Philips Corp
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Filing: 1980-06-18
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Granted: 1983-05-17
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Expires: 2000-06-18
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Abstract

Abstract A traffic light construction which provides a signal of a high luminous intensity, a gradual brightness variation over a cover glass and a considerable suppression of phantom phenomena. The traffic light has a parabolic reflector having a depth of about its focal length and a converging lens smaller than the cover glass. The lens produces a parallel light beam, which is incident on the central portion of the cover glass which is outside the reach of the parallel beam formed by the reflector.

Inventors

  • 👤 Cornelis A. Visser

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 16:05
CPC Classifications
G; G08; G08G; G08G1/00; G08G1/09; G08G1/095; F; F21; F21W; F21W2111/00; F21W2111/02

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 216 words
A traffic light comprising a parabolic reflector, a light source, and a converging lens, the light source being arranged in the common focal point of the reflector and the lens, the reflector having a depth substantially equal to the focal length thereof, a cover glass, said lens being smaller than said cover glass, said reflector extending over substantially the whole area of said cover glass intermediate said cover glass and said light source, said lens being so dimensioned that substantially all light reflected from the reflector passes therethrough in a direction oblique to the optical axis of said lens, the traffic light further including mounting means for said light source, said mounting means blocking all light from reaching said reflector in a central portion of said reflector, the transverse dimensions of said lens corresponding to the transverse dimensions of said central portion of said reflector, and the focal length of said lens being at least equal to that of said reflector, said lens being directly carried on said cover glass, said cover glass having a periphery, said lens being supported with colorless, transparent supporting spokes which have a constant thickness whereby the emerging light rays are parallel to the corresponding incident light rays, said spokes extending to and connected to the periphery of said cover glass.
Claim 2
Dependent Claim 216 words
A traffic light comprising a parabolic reflector, a light source, and a converging lens, the light source being arranged in the common focal point of the reflector and the lens, the reflector having a depth substantially equal to the focal length thereof, a cover glass, said lens being smaller than said cover glass, said reflector extending over substantially the whole area of said cover glass intermediate said cover glass and said light source, said lens being so dimensioned that substantially all light reflected from the reflector passes therethrough in a direction oblique to the optical axis of said lens, the traffic light further including mounting means for said light source, said mounting means blocking all light from reaching said reflector in a central portion of said reflector, the transverse dimensions of said lens corresponding to the transverse dimensions of said central portion of said reflector, and the focal length of said lens being at least equal to that of said reflector, said lens being directly carried on said cover glass, said cover glass having a periphery, said lens being supported with colorless, transparent supporting spokes which have a constant thickness whereby the emerging light rays are parallel to the corresponding incident light rays, said spokes extending to and connected to the periphery of said cover glass.

References Cited (Backward Citations)

US1219514A Cited
US1548984A Cited
DE424062C Cited
US1918480A Cited
US3253255A Cited
US3639899A Cited
DE1951199A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-05-16 1986-11-15 1987-05-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-05-16 1990-11-15 1991-05-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-05-16 1994-11-15 1995-05-17 $7700.00 Window Closed / Lapsed

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