US4095881A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Efficient illumination system
Assignee: International Business Machines Corp
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Filing: 1976-12-20
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Granted: 1978-06-20
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Expires: 1996-12-20
Abstract
Abstract An illumination system of particular use in document copiers wherein an incandescent lamp which may be of the tungsten-halogen type is located at the focal point of a reflector shaped as a conic section such as elliptical cylinder, directing light rays toward an interference filter for separating the IR radiation and redirecting the IR rays back to the incandescent lamp for heating the lamp. Both cold mirror and hot mirror embodiments of the system are disclosed.
Inventors
- 👤 Randall Adrian Maddox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:04
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/024; H04N1/028; H04N1/02815; H04N1/02845; H04N1/0285; F; F21; F21V; F21V7/00; F21V7/04; F21V7/07; F21V7/08; F21V7/09; F21V7/22; F21V7/24; F21V9/00; F21V9/04; G; G03; G03B; G03B27/00; G03B27/32; G03B27/52; G03B27/54; G03B27/542; H04N1/0287; H04N1/02895
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
135 words
An illumination system including an incandescent light source with a filament and bulb wall and including means for separating the visible light spectrum from the infrared spectrum and redirecting a substantial portion of said infrared spectrum to the light source, comprising: a reflector means for reflecting both the infrared and visible spectrum, said reflecting means shaped into a conic section with a focal point, said light source located at the focal point of said reflector means; a filter means for separating said visible light from said infrared light, said filter means receiving rays from said reflector means; and infrared reflecting means receiving rays from said filter means for reflecting at least a substantial portion of said infrared spectrum back upon said light source, whereby said filament and bulb wall are heated by the infrared radiation.
Claim 2
Dependent Claim
135 words
An illumination system including an incandescent light source with a filament and bulb wall and including means for separating the visible light spectrum from the infrared spectrum and redirecting a substantial portion of said infrared spectrum to the light source, comprising: a reflector means for reflecting both the infrared and visible spectrum, said reflecting means shaped into a conic section with a focal point, said light source located at the focal point of said reflector means; a filter means for separating said visible light from said infrared light, said filter means receiving rays from said reflector means; and infrared reflecting means receiving rays from said filter means for reflecting at least a substantial portion of said infrared spectrum back upon said light source, whereby said filament and bulb wall are heated by the infrared radiation.
Claim 3
Dependent Claim
20 words
The illumination system of claim 1 wherein said infra-red reflecting means and said filter means are one and the same.
Claim 4
Dependent Claim
53 words
The illumination system of claim 2 wherein said reflector means is shaped as a partial section of an ellipse and wherein said light source is located at the first focal point of the ellipse and the reflector means focuses light produced by said light source toward the second focal point of said ellipse.
Claim 5
Dependent Claim
41 words
The illumination system of claim 3 wherein said filter means is a plane heat reflecting interference filter located along the minor axis of said ellipse to redirect said infrared rays toward the first focal point where said light source is located.
Claim 6
Dependent Claim
54 words
The illumination system of claim 4 wherein said reflector means is shaped into a full half section of said ellipse and said plane filter is attached to the outer edges of the reflector means along the minor axis, whereby a full 360° of infrared radiation is captured and reflected back upon said light source.
Claim 7
Dependent Claim
66 words
The illumination system of claim 3 wherein said filter means is shaped as a hyperbola with the focal point of the hyperbola coincident with the focal point of said ellipse, and wherein the outer edges of the hyperbolic filter are connected to the outer edges of said elliptical reflector means, whereby a full 360° of infrared radiation is captured and reflected back upon said light source.
Claim 8
Dependent Claim
52 words
The illumination system of claim 1 wherein said means is shaped as a partial section of an ellipse, wherein said light source is located at the first focal point of the ellipse and wherein the reflector means focuses light produced by said light source toward the second focal point of said ellipse.
Claim 9
Dependent Claim
69 words
The illumination system of claim 7 wherein said filter means is positioned at an angle to the minor axis of said ellipse, said filter means crosses said minor axis and is a plane reflector for redirecting the visible spectrum while transmitting the infrared radiation; and said means for reflecting said infrared spectrum is a hyperbolic reflector whose focal point is coincident with the second focal point of said ellipse.
Claim 10
Dependent Claim
63 words
The illumination system of claim 7 wherein said filter means is positioned at an angle to said minor axis, said filter means does not cross said minor axis and is a plane reflector for redirecting the visible spectrum while transmitting the infrared spectrum; and said means for reflecting said infrared spectrum is a plane reflector located along the minor axis of the ellipse.
Claim 11
Dependent Claim
68 words
The illumination system of claim 2 wherein said reflector means is shaped as a partial section of a paraboloid and said light source is located at the focal point of said paraboloid to produce a beam of light; and said filter means is a plane heat reflecting interference filter located perpendicular to said beam of light to redirect said substantial portion of said infrared back toward the paraboloid.
Claim 12
Dependent Claim
106 words
The illumination system of claim 1 wherein said reflector means is shaped as a partial section of a paraboloid and said light source is located at the focal point of said paraboloid to produce a beam of light; said filter means located at an angle to said beam of light to reflect the visible spectrum and allow the infrared to pass directly through; and said means for reflecting said infrared spectrum is a plane reflector located perpendicular to said light beam for receiving infrared passed through said filter and reflecting said infrared back through said filter means to said paraboloid and on to said light source.
Claim 13
Dependent Claim
73 words
In a document copier apparatus with a document station at which light is focused, the system of claim 4 wherein said elliptical reflector forms a section of an elliptical cylinder with a first focal line along which an incandescent tungstenhalogen lamp source is located, and a second focal line toward which light rays from said light source are directed by said reflector for focusing visible light in a line upon the document station.
Claim 14
Dependent Claim
70 words
In a document copier apparatus with a document station at which light is focused, the system of claim 5 wherein said elliptical reflector forms a section of an elliptical cylinder with a first focal line along which an incandescent tungsten-halogen lamp source is located, and a second focal line toward which light rays from said light source are directed by said reflector for focusing visible light upon the document station.
Claim 15
Dependent Claim
72 words
In a document copier apparatus with a document station at which light is focused, the system of claim 6 wherein said elliptical reflector forms a section of elliptical cylinder with a first focal line along which an incandescent tungsten-halogen lamp source is located, and the second focal line toward which light rays from said light source are directed by said reflector for focusing visible light in a line upon the document station.
Claim 16
Dependent Claim
72 words
In a document copier with a document station at which light is focused, the system of claim 8 wherein said elliptical reflector forms a section of an elliptical cylinder with a first focal line along which an incandescent tungsten-halogen lamp source is located, and a second focal line toward which light rays from said light source are directed by said reflector for focusing visible light in a line upon the document station.
Claim 17
Dependent Claim
73 words
In a document copier apparatus with a document station at which light is focused, the system of claim 9 wherein said elliptical reflector forms a section of an elliptical cylinder with a first focal line along which an incandescent tungstenhalogen lamp source is located, and a second focal line toward which light rays from said light source are directed by said reflector for focusing visible light in a line upon the document station.
Claim 18
Dependent Claim
45 words
In a document copier apparatus with a document station at which light is focused, the system of claim 10 wherein said paraboloid reflector directs said beam of light to a parabolic cylindrical scan reflector for focusing visible light in a line upon the document station.
Claim 19
Dependent Claim
45 words
In a document copier apparatus with a document station at which light is focused, the system of claim 11 wherein said paraboloid reflector directs said beam of light to a parabolic cylindrical scan reflector for focusing visible light in a line upon the document station.
References Cited (Backward Citations)
US3038372A
Cited
US3270194A
Cited
US3455622A
Cited
US3411847A
Cited
US3532424A
Cited
US3745325A
Cited
US3947115A
Cited
US3977784A
Cited
US3982116A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-19 | 1981-12-19 | 1982-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-19 | 1985-12-19 | 1986-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-19 | 1989-12-19 | 1990-06-20 | $7700.00 | Window Closed / Lapsed |