US5089943A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Illuminating device, having two identical lamps connected in parallel
Assignee: VDO Luftfahrtgerate Werk GmbH
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Filing: 1990-12-12
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Granted: 1992-02-18
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Expires: 2010-12-12
Abstract
Abstract An illuminating device has two lamps developed as discharge tubes which have a serpentine course and are nested in each other by, in each case, a narrow U-shaped region and a wide U-shaped region. In this way both lamps can be of identical development and permit uniform illumination of a rectangular liquid crystal cell even upon failure of one lamp.
Inventors
- 👤 Lothar Wolfelschneider
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:30
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133602; G02F1/133604; G02F1/133613
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
120 words
An illuminating device for illuminating a rectangular surface, comprising two identical lamps connected electrically in parallel; and means for positioning the lamps in nested arrangement wherein each lamp is developed as a gas-discharge tube of serpentine shape having at least one narrow U-shaped region and an adjoining wider U-shaped region; each lamp has its U-shaped regions nested within the U-shaped regions of the other lamp providing for engagement of the narrow U-shaped region of one lamp into the wider U-shaped region of the other lamp; and each of said lamps has, in sequential order, a first narrow U-shaped region, a wider U-shaped region and, adjoining same, a second narrow U-shaped region which is shorter than the first narrow U-shaped region.
Claim 2
Dependent Claim
120 words
An illuminating device for illuminating a rectangular surface, comprising two identical lamps connected electrically in parallel; and means for positioning the lamps in nested arrangement wherein each lamp is developed as a gas-discharge tube of serpentine shape having at least one narrow U-shaped region and an adjoining wider U-shaped region; each lamp has its U-shaped regions nested within the U-shaped regions of the other lamp providing for engagement of the narrow U-shaped region of one lamp into the wider U-shaped region of the other lamp; and each of said lamps has, in sequential order, a first narrow U-shaped region, a wider U-shaped region and, adjoining same, a second narrow U-shaped region which is shorter than the first narrow U-shaped region.
Claim 3
Dependent Claim
175 words
A liquid crystal cell assembly comprising: a liquid crystal cell; a lightbox disposed behind the cell for directing light through the cell from a back surface of the cell toward a front surface of the cell; two lamps disposed in the box in a coplanar arrangement for generating the light, each of said lamps having a serpentine shape having U-shaped bends, wherein U-shaped bends of a first of the lamps nest between U-shaped bends of the second of the lamps; wherein each lamp is developed as a gas-discharge tube of serpentine shape having at least one narrow U-shaped region and an adjoining wider U-shaped region; each lamp has its U-shaped regions nested within the U-shaped regions of the other lamp providing for engagement of the narrow U-shaped region of one lamp into the wider U-shaped region of the other lamp; and each of said lamps has, in sequential order, a first narrow U-shaped region, a wider U-shaped region and, adjoining same, a second narrow U-shaped region which is shorter than the first narrow U-shaped region.
Claim 4
Dependent Claim
175 words
A liquid crystal cell assembly comprising: a liquid crystal cell; a lightbox disposed behind the cell for directing light through the cell from a back surface of the cell toward a front surface of the cell; two lamps disposed in the box in a coplanar arrangement for generating the light, each of said lamps having a serpentine shape having U-shaped bends, wherein U-shaped bends of a first of the lamps nest between U-shaped bends of the second of the lamps; wherein each lamp is developed as a gas-discharge tube of serpentine shape having at least one narrow U-shaped region and an adjoining wider U-shaped region; each lamp has its U-shaped regions nested within the U-shaped regions of the other lamp providing for engagement of the narrow U-shaped region of one lamp into the wider U-shaped region of the other lamp; and each of said lamps has, in sequential order, a first narrow U-shaped region, a wider U-shaped region and, adjoining same, a second narrow U-shaped region which is shorter than the first narrow U-shaped region.
References Cited (Backward Citations)
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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) | 1995-02-17 | 1995-08-19 | 1996-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-17 | 1999-08-19 | 2000-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-17 | 2003-08-19 | 2004-02-18 | $7700.00 | Window Closed / Lapsed |