Reflector formed with highly reliable conductive pattern, process for fabricating reflector and liquid crystal display unit using the same

• US 20020015124A1
• Filed: 07/05/2001
• Published: 02/07/2002
• Est. Priority Date: 07/06/2000
• Status: Active Grant

• Current Assignee: Vista Peak Ventures LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: NEC LCD Technologies Limited (NEC Corporation)
• Inventors: Kaneko, Hideki, Sato, Yasuhiro, Nishiyama, Michiaki
• Granted Patent: US 6,867,832 B2
• Time in Patent Office: Days
• US Class Current: 349/113
• CPC Class Codes: F21V 23/00 Arrangement of electric circuit elements in or on lighting devices characterised by cooling arrangements F21V29/508
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0065 Manufacturing aspects; Material aspects
• CPC Class Codes: G02B 6/0071 with elongated shape, e.g. tube
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

A reflector is incorporated in a liquid crystal display panel for directing light to an optical path from a lamp to a liquid crystal panel, and a high voltage line is directly connected to an electrode of the lamp, but a low voltage line is connected through a conductive pattern formed on the reflector to the other electrode of the lamp, wherein the conductive pattern is formed from a layer of conductive filler printed on the reflector through thermosetting so that the conductive pattern is thick enough to withstand thermal stress without enlargement of the liquid crystal display unit.

Claims

1. A reflector comprising:

a body formed of insulating resin, and having an outer surface and an inner surface defining a space open to an object to which a light is to be directed, and

a conductive pattern printed on said outer surface for supplying an electric power to a light source placed in said space.

2. The reflector as set forth in claim 1, in which said insulating resin is a thermoplastic resin, and the conductive pattern is formed of thermosetting resin containing conductive material.

3. The reflector as set forth in claim 2, in which said thermoplastic resin is polyethylene terephthalate resin.

4. The reflector as set forth in claim 2, in which said thermoplastic resin is polycarbonate resin.

5. The reflector as set forth in claim 2, in which said thermosetting resin containing conductive material is formed from a layer of conductive filler containing modified copolymerized polyester, silver and carbon.

6. The reflector as set forth in claim 1, in which said body has a first end and a second end respective corresponding to two ends of a lamp, and said conductive pattern extends along a shortest path between said first end and said second end.

7. The reflector as set forth in claim 1, in which a groove is formed in said body, and said conductive pattern is formed in said groove.

8. The reflector as set forth in claim 7, in which said conductive pattern is coplanar with a surface of said body to which said groove is open.

9. The reflector as set forth in claim 1, in which said conductive pattern has plural conductive sub- patterns arranged in parallel to one another.

10. A liquid crystal display unit for producing an image, comprising:

a liquid crystal panel having an incident surface and an image producing surface;

a driving circuit connected to said liquid crystal panel, and varying the transparency of a part of said liquid crystal panel so as to transmit a light from said incident surface to said image producing surface through said part; and

a light source illuminating said light incident surface with said light, and including

a lamp having electrodes and generating said light propagated along an optical path to said liquid crystal panel,

a power supply cable having a conductive pattern and voltage application lines directly connected to one of said electrodes and connected through said conductive pattern to the other of said electrodes, and

a reflector formed of an insulating resin and having an outer surface where said conductive pattern is printed and an inner surface defining a space accommodating said lamp and open to said optical path for directing said light to said optical path.

11. The liquid crystal display unit as set forth in claim 10, in which said insulating resin is a thermoplastic resin, and the conductive pattern is formed of thermosetting resin containing conductive material.

12. The liquid crystal display unit as set forth in claim 11, in which said thermoplastic resin is polyethylene terephthalate resin.

13. The liquid crystal display unit as set forth in claim 11, in which said thermoplastic resin is polycarbonate resin.

14. The liquid crystal display unit as set forth in claim 11, in which said thermosetting resin containing conductive material is formed from a layer of conductive filler containing modified copolymerized polyester, silver and carbon.

15. The liquid crystal display unit as set forth in claim 10, in which said reflector has a first end and a second end respective corresponding to said electrodes of said lamp, and said conductive pattern extends along a shortest path between said first end and said second end.

17. The process as set forth in claim 16, in which said first synthetic resin is a thermoplastic resin, and said conductive pattern is formed of a second synthetic resin implementing a thermosetting resin containing a conductive material.

18. The process as set forth in claim 17, in which said thermoplastic resin is selected from the group consisting of polyethylene terephthalate resin and polycarbonate resin, and said conductive filler contains modified copolymerized polyester, silver and carbon.

19. The process as set forth in claim 16, in which said step a) includes the sub-steps of

a-1) heating said first insulating resin for producing a soft insulating resin,

a-2) extruding said soft insulating resin for forming a hot bar member, and

a-3) cooling said hot bar member for producing said insulating member.

20. The process as set forth in claim 16, in which said step a) includes the sub-steps of

a-1) heating said first insulating resin for producing a soft insulating resin, and

a-2) extruding said soft insulating resin for forming a hot bar member serving as said insulating member.

21. The process as set forth in claim 16, in which said conductive filler is printed by using a dispenser.

16. A process for producing a reflector, comprising the steps of:

a) forming an insulating member from a first synthetic resin;

b) printing a conductive filler on a surface of said insulating member; and

c) solidifying said conductive filler on said surface for producing a conductive pattern.