Patent US5117478A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5117478A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for redirecting light through a hollow tubular light conduit

Assignee: 3M Co
•
Filing: 1991-02-19
•
Granted: 1992-05-26
•
Expires: 2011-02-19
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract When two hollow tubular light conduits are interconnected at a miter joint, beamed light can be redirected from one of the conduits to the other by a thin transparent prismatic element that is mounted to extend along the plane of the miter joint. When the interconnected conduits are acting as a luminaire, the miter joint can be fully illuminated by the transported light. A luminaire of unlimited length can be obtained by mounting a plurality of lamps and parabolic reflectors along a transparent hollow tubular light conduit and redirecting light from each lamp to be transported along the axis of the conduit in both directions.

Inventors

  • 👤 Sanford Cobb, Jr.
  • 👤 Michael J. Leite

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 21:42
CPC Classifications
F; F21; F21V; F21V5/00; G; G02; G02B; G02B19/00; G02B19/0004; G02B19/0028; G02B19/0033; G02B19/0047; G02B6/00; G02B6/0001; G02B6/0096

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 92 words
A device for redirecting a beam of light, said device comprising a source of beamed light including a parabolic reflector, a hollow tubular light conduit, the axis of which is intersected by the axis of the beamed light at an angle of 90 degrees, and a thin transparent prismatic element mounted in the tubular light conduit to intercept and redirect light from the lamp and parabolic reflector along the axis of the tubular light conduit, the prismatic element extending part way but less than all of the way across the light conduit.
Claim 2
Independent Claim 92 words
A device for redirecting a beam of light, said device comprising a source of beamed light including a parabolic reflector, a hollow tubular light conduit, the axis of which is intersected by the axis of the beamed light at an angle of 90 degrees, and a thin transparent prismatic element mounted in the tubular light conduit to intercept and redirect light from the lamp and parabolic reflector along the axis of the tubular light conduit, the prismatic element extending part way but less than all of the way across the light conduit.
Claim 3
Dependent Claim 49 words
A light-redirecting device as defined in claim 1 wherein a second thin transparent prismatic element is mounted at the TIR conduit to intercept light from the lamp and parabolic reflector while extending part way across the TIR conduit at an opposite angle to the axis of the TIR conduit.
Claim 4
Dependent Claim 35 words
A light-redirecting device as defined in claim 2 and further comprising a plurality of lamps, parabolic reflectors, and pairs of said thin transparent prismatic elements mounted in like manner at intervals along the TIR conduit.
Claim 5
Dependent Claim 34 words
A light-redirecting device as defined in claim 3 wherein the spacing between adjacent lamps is selected so that light emitted from each diminishes about 50 percent before reaching the position of an adjacent lamp.
Claim 6
Independent Claim 128 words
A device for redirecting a beam of light, said device comprising a hollow cylindrical TIR conduit comprising transparent dielectric material, a plurality of lamps and parabolic reflectors mounted on the TIR conduit with the axis of each parabolic reflector intersecting the axis of the TIR conduit at an angle of 90 degrees, a pair of thin transparent prismatic elements mounted in the TIR conduit to intercept light from each lamp and parabolic reflector, each element extending part way into the TIR conduit at opposite angles to the axis of the TIR conduit to redirect light from said lamp in opposite directions through the TIR conduit, and adjacent lamps being spaced such that light emitted from each diminishes about 50 percent before reaching the position of an adjacent lamp.
Claim 7
Independent Claim 128 words
A device for redirecting a beam of light, said device comprising a hollow cylindrical TIR conduit comprising transparent dielectric material, a plurality of lamps and parabolic reflectors mounted on the TIR conduit with the axis of each parabolic reflector intersecting the axis of the TIR conduit at an angle of 90 degrees, a pair of thin transparent prismatic elements mounted in the TIR conduit to intercept light from each lamp and parabolic reflector, each element extending part way into the TIR conduit at opposite angles to the axis of the TIR conduit to redirect light from said lamp in opposite directions through the TIR conduit, and adjacent lamps being spaced such that light emitted from each diminishes about 50 percent before reaching the position of an adjacent lamp.
Claim 8
Independent Claim 88 words
A device for redirecting a beam of light, said device comprising first and second hollow tubular light conduits, each having an axis, said light conduits meeting such that said axes form a 90 degree angle and first light conduit terminating at the intersection of said conduits to form a T-shaped joint; and a pair of thin transparent prismatic elements mounted at the intersection of said light conduits and extending into said second light conduit each forming an angle of 45 degrees with each of said light conduit axes.
Claim 9
Independent Claim 88 words
A device for redirecting a beam of light, said device comprising first and second hollow tubular light conduits, each having an axis, said light conduits meeting such that said axes form a 90 degree angle and first light conduit terminating at the intersection of said conduits to form a T-shaped joint; and a pair of thin transparent prismatic elements mounted at the intersection of said light conduits and extending into said second light conduit each forming an angle of 45 degrees with each of said light conduit axes.
Claim 10
Independent Claim 82 words
A device for redirecting a beam of light, said device comprising: first and second hollow tubular light conduits, each having an axis, said light conduits intersecting such that said axes form an angle that does not exceed 60 degrees; and a thin transparent prismatic element mounted at the intersection of said light conduits to intercept and redirect light beamed along said axis of said first light conduit along said axis of said second light conduit, said prismatic element operating entirely by refraction.
Claim 11
Independent Claim 82 words
A device for redirecting a beam of light, said device comprising: first and second hollow tubular light conduits, each having an axis, said light conduits intersecting such that said axes form an angle that does not exceed 60 degrees; and a thin transparent prismatic element mounted at the intersection of said light conduits to intercept and redirect light beamed along said axis of said first light conduit along said axis of said second light conduit, said prismatic element operating entirely by refraction.
Claim 12
Dependent Claim 57 words
A light redirecting device comprising: first, second and third light conduits, each having an axis, said first second, and third light conduits being interconnected so that said axis intersect in a point; and three thin transparent prismatic elements each of which extends along the plane of one of the interconnections for redirecting light among said light conduits.
Claim 13
Dependent Claim 57 words
A light redirecting device comprising: first, second and third light conduits, each having an axis, said first second, and third light conduits being interconnected so that said axis intersect in a point; and three thin transparent prismatic elements each of which extends along the plane of one of the interconnections for redirecting light among said light conduits.
Claim 14
Dependent Claim 27 words
A light-redirecting device as defined in claim 8 wherein said interconnections form miter angles, the planes of which intersect at angles of 120 degrees with each other.

References Cited (Backward Citations)

US586225A Cited
US2248638A Cited
US2844998A Cited
US4684224A Cited
US4850665A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-05-26 1995-11-25 1996-05-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-05-26 1999-11-25 2000-05-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-05-26 2003-11-25 2004-05-26 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag