US4059755A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Luminaire lens insert
Assignee: Armstrong World Industries Inc
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Filing: 1975-12-29
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Granted: 1977-11-22
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Expires: 1995-12-29
Abstract
Abstract A luminaire lens is provided with a prism arrangement which emits light in two beams. A fluorescent tube fixture is utilized with the lens and approximately the same amount of light comes from the 0° to 30° zone of candlepower distribution and the 30° to 60° zone of candlepower distribution, with very little light emitted from the 60° to 90° zone of candlepower distribution. A second lens insert element is provided within the primary luminaire lens to mask the image of the fluorescent tube.
Inventors
- 👤 Grafton K. Brabson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:07
CPC Classifications
F; F21; F21V; F21V5/00; F21V5/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
229 words
An elongated luminaire for illuminating an area therebelow comprising a linear light source, an elongated primary prism having a bottom section formed with a series of parallel prisms extending from the center of the bottom section of the luminaire to the edge of the luminaire, said prisms having an included angle fixed in size and an included angle which increases in size as one progresses from the centermost prism to the edgemost prism of the bottom section, said prisms being formed on the sides thereof facing the light source, said prisms constituting light incident and light emergent surfaces for redirecting and emitting light rays from the light source generally away from a vertical plane passing through the axis of the linear light source and into annular ranges on either side thereof, and a lens insert means between the light source and the primary prism, said lens insert having prisms on the side thereof facing away from the light source, the distribution of light from both the primary prism and lens insert being such that substantially half of the light distribution will emit in an area of 0° to 30° from the vertical plane and substantially the other half of the light is distributed in an area from 30° to 60° from the vertical plane, and the light actually is distributed in two zones either side of the vertical plane.
Claim 2
Dependent Claim
229 words
An elongated luminaire for illuminating an area therebelow comprising a linear light source, an elongated primary prism having a bottom section formed with a series of parallel prisms extending from the center of the bottom section of the luminaire to the edge of the luminaire, said prisms having an included angle fixed in size and an included angle which increases in size as one progresses from the centermost prism to the edgemost prism of the bottom section, said prisms being formed on the sides thereof facing the light source, said prisms constituting light incident and light emergent surfaces for redirecting and emitting light rays from the light source generally away from a vertical plane passing through the axis of the linear light source and into annular ranges on either side thereof, and a lens insert means between the light source and the primary prism, said lens insert having prisms on the side thereof facing away from the light source, the distribution of light from both the primary prism and lens insert being such that substantially half of the light distribution will emit in an area of 0° to 30° from the vertical plane and substantially the other half of the light is distributed in an area from 30° to 60° from the vertical plane, and the light actually is distributed in two zones either side of the vertical plane.
Claim 3
Dependent Claim
307 words
An elongated luminaire for illuminating an area therebelow comprising a linear light source, an elongated primary prism having a bottom section and two side sections on either side of the bottom section, said bottom section of the luminaire is formed with a series of parallel prisms extending from the center of the bottom section of the luminaire to the edge of the luminaire, said prisms having an included angle fixed in size and an included angle which increases in size as one progresses from the centermost prism to the edgemost prism of the bottom section, the sides of the luminaire have a plurality of parallel prisms which extend from adjacent the bottom section to adjacent the top of the side section and said prisms have a fixed size included angle and an included angle which increases in size as one moves from adjacent the bottom section to adjacent the top of the side section, said sections having prisms formed on the sides thereof facing the light source, said prisms constituting light incident and light emergent surfaces for redirecting and emitting light rays from the light source generally away from a vertical plane passing through the axis of the linear light source and into annular ranges on either side thereof, and a lens insert means between the light source and the primary prism, said lens insert having prisms on the side thereof facing away from the light source, the distribution of light from both the primary prism and lens insert being such that substantially half of the light distribution will emit in an area of 0° to 30° from the vertical plane and substantially the other half of the light is distributed in an area from 30° to 60° from the vertical plane, and the light actually is distributed in two zones either side of the vertical plane.
Claim 4
Dependent Claim
307 words
An elongated luminaire for illuminating an area therebelow comprising a linear light source, an elongated primary prism having a bottom section and two side sections on either side of the bottom section, said bottom section of the luminaire is formed with a series of parallel prisms extending from the center of the bottom section of the luminaire to the edge of the luminaire, said prisms having an included angle fixed in size and an included angle which increases in size as one progresses from the centermost prism to the edgemost prism of the bottom section, the sides of the luminaire have a plurality of parallel prisms which extend from adjacent the bottom section to adjacent the top of the side section and said prisms have a fixed size included angle and an included angle which increases in size as one moves from adjacent the bottom section to adjacent the top of the side section, said sections having prisms formed on the sides thereof facing the light source, said prisms constituting light incident and light emergent surfaces for redirecting and emitting light rays from the light source generally away from a vertical plane passing through the axis of the linear light source and into annular ranges on either side thereof, and a lens insert means between the light source and the primary prism, said lens insert having prisms on the side thereof facing away from the light source, the distribution of light from both the primary prism and lens insert being such that substantially half of the light distribution will emit in an area of 0° to 30° from the vertical plane and substantially the other half of the light is distributed in an area from 30° to 60° from the vertical plane, and the light actually is distributed in two zones either side of the vertical plane.
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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) | 1980-11-21 | 1981-05-23 | 1981-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-21 | 1985-05-23 | 1985-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-21 | 1989-05-23 | 1989-11-22 | $7700.00 | Window Closed / Lapsed |