LCD in which lamp reflector is grounded to panel housing via screw, pinch fastening, or snap pressing means

• US 6,480,245 B1
• Filed: 11/17/2000
• Issued: 11/12/2002
• Est. Priority Date: 03/26/1999
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Advanced Display Technologies
• Inventors: Sakamoto, Takuya, Hayasaki, Hiroshige
• Primary Examiner(s): Ton, Toan
• Assistant Examiner(s): SCHECHTER, ANDREW M
• Application Number:
  US09/700,660
• Time in Patent Office: 725 Days
• Field of Search: 349/58, 349/59, 349/60, 349/65, 349/67
• US Class Current: 349/59
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0083 Details of electrical connections of light sources to drivers, circuit boards, or the like
• CPC Class Codes: G02B 6/0086 Positioning aspects
• CPC Class Codes: G02F 1/133308 Support structures for LCD panels, e.g. frames or bezels
• CPC Class Codes: G02F 1/133334 Electromagnetic shields
• CPC Class Codes: G02F 1/133608 including particular frames or supporting means
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 2201/46 Fixing elements

Abstract

A liquid crystal display device includes: a transmission-type liquid crystal panel; a sheet-like light source device for radiating light to a back surface of the liquid crystal panel, the sheet-like light source device including a lamp, a conducting lamp reflector, and a light-conducting plate; a circuit board connected to the liquid crystal panel for supplying a signal necessary for driving the liquid crystal panel; and a mechanism part for housing and holding all three of the liquid crystal panel, the sheet-like light source device, and the circuit board. The mechanism part includes at least one metal part, and the at least one metal part is fixedly attached to the lamp reflector via any one of a screw fastening member, a pinch fastening member, or a snap fastening member. The liquid crystal display device is capable of reducing display deficiencies due to electric noise and is also capable of obtaining clearer images.

Claims

1. A liquid crystal display device comprising:

a transmission-type liquid crystal panel;

a sheet-like light source device for radiating light to a back surface of said transmission-type liquid crystal panel, said sheet-like light source device including a lamp, a conductive lamp reflector, and a light-conducting plate;

a circuit board connected to said transmission-type liquid crystal panel for supplying a signal necessary for driving said transmission-type liquid crystal panel;

a mechanism part for housing and holding all three of said transmission-type liquid crystal panel, said sheet-like light source device, and said circuit board, wherein said mechanism part includes at least one metal part, and wherein said at least one metal part is fixedly attached to said lamp reflector via a fastening means, said at least one metal part and said lamp reflector each being in contact with said fastening means, and said fastening means uniting said at least one metal part and said lamp reflector into a single piece.

2. The liquid crystal display device of claim 1, wherein said at least one metal part to be connected to said lamp reflector forms at least a portion of a display surface side and a portion of a side of said transmission-type liquid crystal display device.

3. The liquid crystal display device of claim 1, wherein said at least one metal part to be connected to said lamp reflector forms at least a portion of a back surface of said transmission-type liquid crystal display device.

4. The liquid crystal display device of claim 1, wherein said at least one metal part to be connected to said lamp reflector forms at least a portion of a back surface and a portion of a side of said transmission-type liquid crystal display device.

5. The liquid crystal display device of claim 1, wherein said at least one metal part to be connected to said lamp reflector is so arranged to cover said lamp reflector.

6. The liquid crystal display device of claim 1, wherein said fastening means is a screw fastening means having threads on an outer peripheral surface of a shank of said screw fastening means, said threads on said outer peripheral surface of said shank of said screw fastening means mating with threads in outer peripheral surfaces of a hole in said at least one metal part and a hole in said lamp reflector.

7. The liquid crystal display device of claim 6, wherein, at a fixation portion through said screw fastening means, said at least one metal part is fixedly attached to said lamp reflector and a lamp cover.

8. The liquid crystal display device of claim 6, wherein said screw fastening means is composed of either both a screw and a female screw working or both a screw and a calking nut.

9. The liquid crystal display device of claim 1, wherein said fastening means is a snap pressing means for achieving fixed attachment in a freely attachable/detachable manner, said snap pressing means being a pin member having a slit through a shank of said pin member in a longitudinal direction of said shank so as to form first and second leg members on an end of said pin member, said first and second leg members moving slightly towards and away from each other when said pin is being snap-fitted into holes in said at least one metal part and said lamp reflector.

10. The liquid crystal display device of claim 9, wherein at a fixation portion through said snap pressing means, said at least one metal part is fixedly attached to said lamp reflector and a lamp cover.

11. A liquid crystal display device comprising:

a transmission-type liquid crystal panel;

a sheet-like light source device for radiating light to a back surface of said transmission-type liquid crystal panel, said sheet-like light source device including at least a lamp, a conductive lamp reflector and a light-conducting plate;

a circuit board connected to said transmission-type liquid crystal panel for supplying signal necessary for driving said transmission-type liquid crystal panel;

a mechanism part for housing and holding said transmission-type liquid crystal panel, said sheet-like light source device and said circuit board, wherein said mechanism part includes at least one metal part, and wherein said at least one metal part is fixedly attached to said lamp reflector via a pinch fastening means obtained by plastic working.

12. The liquid crystal display device of claim 11, wherein said pinch fastening means is obtained by first inserting either one of a protruding piece or a protruding cylindrical body protruding from either said lamp reflecting or said at least one metal part into a hole formed at either said at least one metal part or said lamp reflector, respectively and then, crushing either one of said protruding piece or said protruding cylindrical body.

13. The liquid crystal display device of claim 11, wherein, at a fixation portion through said pinch fastening means obtained by the plastic working, said at least one metal part is fixedly attached to said lamp reflector and a lamp cover.