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US4954930A Expired / Lapsed US ⏱️ 0.0 years remaining

Illumination light guide

Assignee: Alps Alpine Co Ltd
•
Filing: 1989-09-25
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Granted: 1990-09-04
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Expires: 2009-09-25
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Abstract

Abstract An illumination light guide includes a plurality of elongated illuminating portions; a light guiding path portion connecting one end of each of the illuminating portions; a light receiving portion formed in the light guiding path portion; a plurality of light distributing/reflecting portions formed in the light guiding path portion so as to correspond to the illuminating portions and having different lengths such that the longer a distance from the light receiving portion to one of the light distributing/reflecting portions, the longer a length of the one of the light distributing/reflecting portions; and a plurality of light reflecting portions formed at the other ends of the illuminating portions, respectively. With this structure, the light emitted from a single light source is received by the light receiving portion, and is uniformly distributed and reflected by the light distributing/reflecting portions and transmitted into the respective illuminating portions. Light transmitted through the illuminating portions is also reflected by the respective light reflecting portions, and is returned into the adjacent illuminating portions to ensure uniform illumination.

Inventors

  • 👤 Mamoru Maegawa
  • 👤 Fumio Sakamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 12:27
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0033; G02B6/0035; G02B6/0045; G02B6/0046; G02B6/0066; G02B6/0073

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 136 words
An illumination light guide comprising: a plurality of elongated illuminating portions; a light guiding path portion connecting one end of each of said illuminating portions; a light receiving portion formed in said light guiding path portion; a plurality of light distirbuting/reflecting portions formed in said light guiding path portion so as to correspond to said illuminating portions and having different lengths such that the longer a distance from said light receiving portion to one of said light distributing/ reflecting portions, the longer a length of the one of said light distributing/reflecting portions; a plurality of light reflecting portions formed at the other ends of said illuminating portions, respectively ; and a plurality of slant surfaces for reflecting light upwardly, a single one of said slant surfaces formed at the bottom of each of said illuminating portions.
Claim 2
Dependent Claim 136 words
An illumination light guide comprising: a plurality of elongated illuminating portions; a light guiding path portion connecting one end of each of said illuminating portions; a light receiving portion formed in said light guiding path portion; a plurality of light distirbuting/reflecting portions formed in said light guiding path portion so as to correspond to said illuminating portions and having different lengths such that the longer a distance from said light receiving portion to one of said light distributing/ reflecting portions, the longer a length of the one of said light distributing/reflecting portions; a plurality of light reflecting portions formed at the other ends of said illuminating portions, respectively ; and a plurality of slant surfaces for reflecting light upwardly, a single one of said slant surfaces formed at the bottom of each of said illuminating portions.
Claim 3
Dependent Claim 28 words
The illumination light guide of claim 1 wherein said plurality of light reflecting portions are formed to reflect light from a corresponding illuminating portion to adjacent illuminating portions.
Claim 4
Dependent Claim 34 words
The illumination light guide of claim 2 wherein each of said light distributing/reflecting portions are formed at an angle between 90 and 180 degrees with respect to the elongated direction of said illuminating portions.

References Cited (Backward Citations)

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US2671163A Cited
US3043038A Cited
US3223833A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-09-03 1994-03-05 1994-09-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-09-03 1998-03-05 1998-09-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-09-03 2002-03-05 2002-09-04 $7700.00 Window Closed / Lapsed

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