US5390085A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light diffuser for a liquid crystal display
Assignee: Motorola Solutions Inc
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Filing: 1993-11-19
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Granted: 1995-02-14
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Expires: 2013-11-19
Abstract
Abstract A light diffuser (100) for illuminating a display (304) comprises a rectangular light distributor (108) which is coupled to a light director (208) located along an edge normal to a major axis (110) of the light distributor (108). The light director (208) directs light received from a lamp (14) into the light distributor (108). The light distributor (108) has a polished, planar top surface (210) and a bottom surface (112) comprising a predetermined serration pattern oriented normal to the major axis (110) of the rectangular light distributor (108). The predetermined serration pattern comprises a plurality of grooves (116, 118, 120) having a predetermined pitch gradient corresponding thereto. The plurality of grooves (116, 118, 120) further have roughened surfaces for diffusing light impinging thereon toward the polished, planar top surface (210) of the light distributor (108). The light impinging on the polished, planar top surface (210) at less than a critical angle is coupled through the polished, planar top surface (210 ) to uniformly illuminate the display (304).
Inventors
- 👤 Gerardo M. Mari-Roca
- 👤 Lori Vaughn
- 👤 Jeffrey S. King
- 👤 Kevin W. Jelley
- 👤 Alan G. Chen
- 👤 George T. Valliath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:52
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0013; G02B6/0015; G02B6/0018; G02B6/0033; G02B6/0058; G02B6/0061; G02B6/0035; G02B6/0036; Y; Y10; Y10S; Y10S362/00; Y10S362/802
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
141 words
A light diffuser for illuminating a display comprising: a rectangular light distributor, coupled to a light director located along an edge normal to a major axis of said light distributor, said light director for directing light received from a lamp into said light distributor; said light distributor having a polished, planar top surface, and a bottom surface comprising a predetermined serration pattern oriented normal to said major axis of said rectangular light distributor; said predetermined serration pattern comprising a plurality of grooves having a predetermined pitch gradient corresponding thereto; said plurality of grooves further having roughened surfaces for diffusing light impinging thereon toward said polished, planar top surface; and whereby the light impinging on said polished, planar top surface at less than a critical angle from said roughened surfaces of said grooves is coupled there through to uniformly illuminate the display.
Claim 2
Dependent Claim
141 words
A light diffuser for illuminating a display comprising: a rectangular light distributor, coupled to a light director located along an edge normal to a major axis of said light distributor, said light director for directing light received from a lamp into said light distributor; said light distributor having a polished, planar top surface, and a bottom surface comprising a predetermined serration pattern oriented normal to said major axis of said rectangular light distributor; said predetermined serration pattern comprising a plurality of grooves having a predetermined pitch gradient corresponding thereto; said plurality of grooves further having roughened surfaces for diffusing light impinging thereon toward said polished, planar top surface; and whereby the light impinging on said polished, planar top surface at less than a critical angle from said roughened surfaces of said grooves is coupled there through to uniformly illuminate the display.
Claim 3
Dependent Claim
16 words
The light diffuser according to claim 1, wherein said rectangular light distributor comprises a transparent material.
Claim 4
Dependent Claim
17 words
The light diffuser according to claim 1, wherein said rectangular light distributor has a substantially uniform thickness.
Claim 5
Dependent Claim
28 words
The light diffuser according to claim 1, wherein said serration pattern comprises a plurality of linear grooves oriented normal to said major axis of said rectangular light distributor.
Claim 6
Dependent Claim
35 words
The light diffuser according to claim 1, wherein said serration pattern comprises a plurality of paired linear grooves oriented at an angle opposite to and bisected by said major axis of said rectangular light distributor.
Claim 7
Dependent Claim
31 words
The light diffuser according to claim 1, wherein said serration pattern comprises a plurality of arctuate grooves oriented normal to and bisected by said major axis of said rectangular light distributor.
Claim 8
Dependent Claim
37 words
The light diffuser according to claim 1, wherein said pitch gradient increasingly varies a depth of said plurality of grooves continuously from the point proximal to said light collector to the point distal to said light collector.
Claim 9
Dependent Claim
42 words
The light diffuser according to claim 1, wherein said pitch gradient varies a depth of said plurality of grooves in a predetermined groups of said grooves from a point proximal to said light collector to a point distal to said light collector.
Claim 10
Dependent Claim
49 words
The light diffuser according to claim 1, wherein said light director comprises: a light collector, positioned below said bottom surface of said light distributor, for collecting the light generated by said lamp; and a faceted reflecting element for reflecting substantially all of the collected light into said light distributor.
Claim 11
Independent Claim
156 words
A system for back lighting a liquid crystal display, comprising: a lamp for generating light; and a light director, optically coupled to said lamp, and further coupled to a light distributor at an edge normal to a major axis thereof, for directing the light received from said lamp into said light distributor, and said light distributor comprising a transparent material and having a polished, top surface, and a bottom surface comprising a predetermined serration pattern oriented normal to said major axis of said light distributor, said predetermined serration pattern comprising a plurality of grooves having a predetermined pitch gradient corresponding thereto, said plurality of grooves further having roughened surfaces for diffusing light impinging thereon toward said polished, planar top surface, and whereby the light impinging on said polished, planar top surface at less than a critical angle from said roughened surfaces of said grooves is coupled there through to substantially uniformly illuminate the liquid crystal display.
Claim 12
Independent Claim
156 words
A system for back lighting a liquid crystal display, comprising: a lamp for generating light; and a light director, optically coupled to said lamp, and further coupled to a light distributor at an edge normal to a major axis thereof, for directing the light received from said lamp into said light distributor, and said light distributor comprising a transparent material and having a polished, top surface, and a bottom surface comprising a predetermined serration pattern oriented normal to said major axis of said light distributor, said predetermined serration pattern comprising a plurality of grooves having a predetermined pitch gradient corresponding thereto, said plurality of grooves further having roughened surfaces for diffusing light impinging thereon toward said polished, planar top surface, and whereby the light impinging on said polished, planar top surface at less than a critical angle from said roughened surfaces of said grooves is coupled there through to substantially uniformly illuminate the liquid crystal display.
Claim 13
Dependent Claim
18 words
The system for back lighting a liquid crystal display according to claim 10, wherein said lamp is tubular.
Claim 14
Dependent Claim
55 words
The system for back lighting a liquid crystal display according to claim 10, wherein said light director comprises: a light collector, positioned below said bottom surface of said light distributor, for collecting the light generated by said lamp; and a faceted reflecting element for reflecting substantially all of the collected light into said light distributor.
Claim 15
Dependent Claim
23 words
The system for back lighting a liquid crystal display according to claim 10, wherein said rectangular light distributor has a substantially uniform thickness.
Claim 16
Dependent Claim
34 words
The system for back lighting a liquid crystal display according to claim 10, wherein said serration pattern comprises a plurality of linear grooves oriented normal to said major axis of said rectangular light distributor.
Claim 17
Dependent Claim
41 words
The system for back lighting a liquid crystal display according to claim 10, wherein said serration pattern comprises a plurality of paired linear grooves oriented at an angle opposite to and bisected by said major axis of said rectangular light distributor.
Claim 18
Dependent Claim
37 words
The system for back lighting a liquid crystal display according to claim 10, wherein said serration pattern comprises a plurality of arctuate grooves oriented normal to and bisected by said major axis of said rectangular light distributor.
Claim 19
Dependent Claim
43 words
The system for back lighting a liquid crystal display according to claim 10, wherein said pitch gradient increasingly varies a depth of said plurality of grooves continuously from the point proximal to said light collector to the point distal to said light collector.
Claim 20
Dependent Claim
48 words
The system for back lighting a liquid crystal display according to claim 10, wherein said pitch gradient varies a depth of said plurality of grooves in a predetermined groups of said grooves from a point proximal to said light collector to a point distal to said light collector.
Claim 21
Dependent Claim
236 words
A communication receiver, comprising: a receiver for receiving message information including an address; a decoder, coupled to said receiver, for decoding the address to detect message information directed to the communication receiver; a display for displaying information including the received message information; a controller, responsive to said decoder and coupled to said display, for controlling the display of the information including the message information and a back lighting system, responsive to information being displayed on said display, comprising a lamp, responsive to said controller, for generating light for illumination; a light director, optically coupled to said lamp, and further coupled to a light distributor at an edge normal to a major axis thereof, for directing the light received from said lamp into said light distributor, and said light distributor comprising a transparent material and having a polished, top surface, and a bottom surface comprising a predetermined serration pattern oriented normal to said major axis of said light distributor, said predetermined serration pattern comprising a plurality of grooves having a predetermined pitch gradient corresponding thereto, said plurality of grooves further having roughened surfaces for diffusing light impinging thereon toward said polished, planar top surface, and whereby the light impinging on said polished, planar top surface at less than a critical angle from said roughened surfaces of said grooves is coupled there through to substantially uniformly illuminate the information including the message information being displayed on said display.
Claim 22
Dependent Claim
236 words
A communication receiver, comprising: a receiver for receiving message information including an address; a decoder, coupled to said receiver, for decoding the address to detect message information directed to the communication receiver; a display for displaying information including the received message information; a controller, responsive to said decoder and coupled to said display, for controlling the display of the information including the message information and a back lighting system, responsive to information being displayed on said display, comprising a lamp, responsive to said controller, for generating light for illumination; a light director, optically coupled to said lamp, and further coupled to a light distributor at an edge normal to a major axis thereof, for directing the light received from said lamp into said light distributor, and said light distributor comprising a transparent material and having a polished, top surface, and a bottom surface comprising a predetermined serration pattern oriented normal to said major axis of said light distributor, said predetermined serration pattern comprising a plurality of grooves having a predetermined pitch gradient corresponding thereto, said plurality of grooves further having roughened surfaces for diffusing light impinging thereon toward said polished, planar top surface, and whereby the light impinging on said polished, planar top surface at less than a critical angle from said roughened surfaces of said grooves is coupled there through to substantially uniformly illuminate the information including the message information being displayed on said display.
Claim 23
Dependent Claim
32 words
The communication receiver according to claim 19, wherein said communication receiver further includes a switch activatable by a user and coupled to said controller, for controlling the illumination provided by said lamp.
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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) | 1998-02-13 | 1998-08-15 | 1999-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-02-13 | 2002-08-15 | 2003-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-02-13 | 2006-08-15 | 2007-02-14 | $7700.00 | Window Closed / Lapsed |