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US4989125A Expired / Lapsed US ⏱️ 0.0 years remaining

Reflector using fresnel-type structures having a plurality of active faces

Assignee: 3M Co
•
Filing: 1988-05-10
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Granted: 1991-01-29
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Expires: 2008-05-10
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Abstract

Abstract A reflector has a plurality of Fresnel-type structures, wherein at least some of said Fresnel-type structures have a plurality of active faces, for reflecting light in a plurality of directions.

Inventors

  • 👤 Sanford Cobb, Jr.
  • 👤 Richard A. Miller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 00:34
CPC Classifications
F; F21; F21V; F21V7/00; F21V7/04; F21V7/0091; F21V7/09

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 98 words
A lighting fixture comprising: a housing forming an optical cavity; an optical window in said housing; a light source in said optical cavity; and a reflector having a plurality of Fresnel-type structures on a side of said housing opposing said optical window, at least some of said Fresnel-type structures comprising two adjacent active faces and a riser, one of said active faces being positioned to collimate light from said light source and the other of said active faces being positioned to reflect light from said light source to a location on said optical window adjacent said light source.
Claim 2
Dependent Claim 98 words
A lighting fixture comprising: a housing forming an optical cavity; an optical window in said housing; a light source in said optical cavity; and a reflector having a plurality of Fresnel-type structures on a side of said housing opposing said optical window, at least some of said Fresnel-type structures comprising two adjacent active faces and a riser, one of said active faces being positioned to collimate light from said light source and the other of said active faces being positioned to reflect light from said light source to a location on said optical window adjacent said light source.
Claim 3
Dependent Claim 14 words
The lighting fixture of claim 1 wherein said Fresnel-type structures are circular and concentric.
Claim 4
Dependent Claim 54 words
The lighting fixture of claim 2 wherein at least some of said Fresnel-type structures comprise two active faces and a riser, one of said active faces being positioned to collimate light from said light source and the other of said active faces being positioned to reflect light radially outward, away from said light source.
Claim 5
Dependent Claim 79 words
The lighting fixture of claim 2 wherein at least some of said Fresnel-type structures comprise three active faces and a riser, one of said active faces being positioned to collimate light from said light source, another of said active faces being positioned to reflect light from said light source to a position on said optical window adjacent said light source and the other of said active faces being positioned to reflect light radially outward, away from said light source.
Claim 6
Dependent Claim 74 words
A reflector having a plurality of Fresnel-type structures at least some of said Fresnel-type structures comprising first and second active faces and a riser, said first active faces being arranged to reflect light in a first predetermined direction and said second active faces being arranged to reflect light in a second predetermined direction, said second predetermined direction being different from said first predetermined direction, said first and second active faces being adjacent one another.
Claim 7
Dependent Claim 74 words
A reflector having a plurality of Fresnel-type structures at least some of said Fresnel-type structures comprising first and second active faces and a riser, said first active faces being arranged to reflect light in a first predetermined direction and said second active faces being arranged to reflect light in a second predetermined direction, said second predetermined direction being different from said first predetermined direction, said first and second active faces being adjacent one another.
Claim 8
Dependent Claim 23 words
The reflector of claim 5 wherein at least some of said Fresnel-type structures comprise first, second and third active faces and a riser.
Claim 9
Dependent Claim 13 words
The reflector of claim 6 wherein said Fresnel-type structures are circular and concentric.
Claim 10
Dependent Claim 43 words
A reflector having a plurality of Fresnel-type structures, said Fresnel-type structures having bases defining a plane, at least some of said Fresnel-type structures comprising two adjacent active faces and a riser, each of said active faces making an acute angle with said plane.
Claim 11
Dependent Claim 43 words
A reflector having a plurality of Fresnel-type structures, said Fresnel-type structures having bases defining a plane, at least some of said Fresnel-type structures comprising two adjacent active faces and a riser, each of said active faces making an acute angle with said plane.
Claim 12
Dependent Claim 32 words
The reflector of claim 8 wherein at least some of said Fresnel-type structures comprise three active faces and a riser, each of said active faces making an acute angle with said plane.
Claim 13
Dependent Claim 13 words
The reflector of claim 9 wherein said Fresnel-type structures are circular and concentric.

References Cited (Backward Citations)

US1554315A Cited
FR696573A Cited
US2421277A Cited
US3710095A Cited
US4041306A Cited
JPS54161769A Cited
US4360863A Cited
FR2525733A1 Cited
US4655546A Cited
US4680679A Cited
US4704661A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-01-28 1994-07-30 1995-01-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-01-28 1998-07-30 1999-01-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-01-28 2002-07-30 2003-01-29 $7700.00 Window Closed / Lapsed

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