US4748546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent backlighting unit
Assignee: Honeywell International Inc
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Filing: 1987-02-02
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Granted: 1988-05-31
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Expires: 2007-02-02
Abstract
Abstract A lighting unit (11) for providing diffused light is particularly useful for back illumination of a flat panel active matrix display (21). The unit (11) includes one or more fluorescent lamp tubes (13,15) which are embedded in RTV rubber or other transparent potting material (29). A pair of diffusing layers (31,35) cause the light output from the unit (11) to be evenly distributed. A ground plane (27) acts as a reflector, a heat sink and permits partial-power operation. Advantages include reduced flicker and an ability to withstand rough service.
Inventors
- 👤 Orest J. Ukrainsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:38
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133602; G02F1/133604; F; F21; F21V; F21V31/00; G02F2201/00; G02F2201/50; G02F2201/503
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
114 words
Flat panel type display unit in which an optically passive active matrix display panel provides a display by means of changes in light transmissivity patterns on the panel, and further including a light source located behind the display panel, in which the light display selectively transmits light from the light source in order to provide a visual display of information, characterized by: (a) the light source including at least one fluorescent lamp; (b) the fluorescent lamp being embedded in a substantially transparent potting material; (c) a conductive backplane located in close proximity to the fluorescent lamp; and (d) at least one light diffusion substrate being intraposed between the fluorescent lamp and the display panel.
Claim 2
Dependent Claim
114 words
Flat panel type display unit in which an optically passive active matrix display panel provides a display by means of changes in light transmissivity patterns on the panel, and further including a light source located behind the display panel, in which the light display selectively transmits light from the light source in order to provide a visual display of information, characterized by: (a) the light source including at least one fluorescent lamp; (b) the fluorescent lamp being embedded in a substantially transparent potting material; (c) a conductive backplane located in close proximity to the fluorescent lamp; and (d) at least one light diffusion substrate being intraposed between the fluorescent lamp and the display panel.
Claim 3
Dependent Claim
60 words
Display unit as described in claim 1, further characterized by: the conductive backplane being connected to a common potential which is at variance with an average potential applied to the lamp when the lamp is illuminated; and the conductive backplane being located sufficently close to the fluorescent lamp to allow capacitive coupling between the fluorescent lamp and the conductive backplane.
Claim 4
Dependent Claim
20 words
Display unit as described in claim 2, further characterized by: the display panel being a flat panel active matrix display.
Claim 5
Dependent Claim
43 words
Display unit as described in claim 1, further characterized by: the conductive backplane being connected to a ground potential; and the conductive backplane being located sufficently close to the fluorescent lamp to allow capacitive coupling between the fluorescent lamp and the conductive backplane.
Claim 6
Dependent Claim
20 words
Display unit as described in claim 4, further characterized by: the display panel being a flat panel active matrix display.
Claim 7
Dependent Claim
20 words
Display unit as described in claim 1, further characterized by: the display panel being a flat panel active matrix display.
Claim 8
Dependent Claim
28 words
Display unit as described in claim 1, further characterized by: at least one additional light diffusing layer, the additional light diffusing layer being embedded in the potting material.
Claim 9
Dependent Claim
19 words
Display unit as described in claim 7, further characterized by: the potting material being RTV (room temperature vulcanizing) silicone.
Claim 10
Dependent Claim
19 words
Display unit as described in claim 1, further characterized by: the potting material being RTV (room temperature vulcanizing) silicone.
Claim 11
Dependent Claim
82 words
Diffused light source having a front exterior surface characterized by: (a) the light source including at least one fluorescent lamp; (b) the fluorescent lamp being embedded in a substantially transparent potting material; (c) a conductive backplane located in close proximity to the fluorescent lamp; (d) at least one light diffusion substrate being intraposed between the fluorescent lamp and the front exterior surface; and (e) at least one additional light diffusing layer, the additional light diffusing layer being embedded in the potting material.
Claim 12
Dependent Claim
82 words
Diffused light source having a front exterior surface characterized by: (a) the light source including at least one fluorescent lamp; (b) the fluorescent lamp being embedded in a substantially transparent potting material; (c) a conductive backplane located in close proximity to the fluorescent lamp; (d) at least one light diffusion substrate being intraposed between the fluorescent lamp and the front exterior surface; and (e) at least one additional light diffusing layer, the additional light diffusing layer being embedded in the potting material.
Claim 13
Dependent Claim
43 words
Display unit as described in claim 10, further characterized by: the conductive backplane being connected to a ground potential; and the conductive backplane being located sufficently close to the fluorescent lamp to allow capacitive coupling between the fluorescent lamp and the conductive backplane.
Claim 14
Dependent Claim
19 words
Display unit as described in claim 11, further characterized by: the potting material being RTV (room temperature vulcanizing) silicone.
Claim 15
Dependent Claim
19 words
Duplex unit as described in claim 10, further characterized by: the potting material being RTV (room temperature vulcanizing) silicone.
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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) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |