Image display device including multiple light source substrates

• US 10,642,097 B2
• Filed: 08/30/2016
• Issued: 05/05/2020
• Est. Priority Date: 09/01/2015
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Kumamoto, Yasuhiro, Shinya, Takeichi, Higa, Koujirou, Ofuji, Masaaki, Takeuchi, Taizou, Kugimaru, Tadahiro
• Primary Examiner(s): Landis, Lisa S
• Application Number:
  US15/750,886
• Publication Number:
  US 20180231838A1
• Time in Patent Office: 1,344 Days
• CPC Class Codes: F21S 2/00 Systems of lighting devices, not provided for in main groups F21S4/00 - F21S10/00 or F21S19/00, e.g. of modular construction
• CPC Class Codes: F21V 19/001 the light sources being semiconductors devices, e.g. LEDs
• CPC Class Codes: F21V 23/001 the elements being electrical wires or cables
• CPC Class Codes: G02F 1/133 Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements arrangements or circuits for control of liquid crystal elements in a matrix, not structurally associated with these elements G09G3/36
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133612 Electrical details
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A video display device includes a liquid crystal display panel, and a plurality of light source substrates configured to illuminate the liquid crystal display panel from a rear side of the liquid crystal display panel. Each of the plurality of light source substrates includes a signal input connector that receives a control signal, a plurality of light emitting diodes each of which is provided in correspondence with a corresponding one of areas different from each other in the liquid crystal display panel, a driver element that drives each of the plurality of light emitting diodes in accordance with the control signal such that each of the plurality of light emitting diodes emits light with luminance corresponding to brightness of the corresponding area of an image, and a signal output connector that through-outputs the control signal. The signal output connector of a first light source substrate included in the plurality of light source substrates, and the signal input connector of a second light source substrate included in the plurality of light source substrates are electrically connected.

Claims

1. A video display device comprising:

a liquid crystal display panel; and

a plurality of light source substrates configured to illuminate the liquid crystal display panel from a rear side of the liquid crystal display panel, wherein;

each of the plurality of light source substrates is disposed along the liquid crystal display panel and in a direction of row and in a direction of column,

each of the plurality of light source substrates includes;

a signal input connector that receives a control signal,

a plurality of light emitting diodes each of which is provided in correspondence with a corresponding one of areas different from each other in the liquid crystal display panel,

a driver that drives each of the plurality of light emitting diodes in accordance with the control signal such that each of the plurality of light emitting diodes emits light with luminance corresponding to brightness of the corresponding area of an image, and

a signal output connector that through-outputs the control signal, and

the signal output connector of a first light source substrate included in the plurality of light source substrates and the signal input connector of a second light source substrate included in the plurality of light source substrates are electrically connected.

2. The video display device according to claim 1, further comprising a plurality of signal systems, wherein:

each of the plurality of light source substrates belongs to any one of the plurality of signal systems,

the video display device further comprises a signal processing substrate that generates the control signal for each of the plurality of signal systems, and

a group of the plurality of light source substrates that belong to the same one of the plurality of signal systems are connected in series via cable connection provided between the signal output connector and the signal input connector of adjacent light source substrates in the group, and allow the control signal generated by the signal processing substrate for the corresponding signal system to be transmitted in series between the corresponding light source substrates.

3. The video display device according to claim 2, wherein:

each of the plurality of light source substrates further includes

a cascade input connector that receives the control signal, and

a cascade output connector that through-outputs the control signal,

a group of the plurality of the light source substrates functioning as representative light source substrates are provided such that each of the group of the plurality of light source substrates functioning as the representative light source substrates is associated with the corresponding one of the signal systems,

the representative light source substrates are connected in series via cable connection provided between the cascade output connector and the cascade input connector of adjacent ones of the representative light source substrates, and allow the control signal generated by the signal processing substrate for the plurality of signal systems to be transmitted in series between the corresponding representative light source substrates, and

each of the representative light source substrates outputs, to the signal output connector, the control signal of the signal system to which the corresponding representative light source substrate belongs.

4. The video display device according to claim 3, wherein

the plurality of light source substrates are disposed in matrix,

light source substrates disposed in a row or a column among the plurality of light source substrates belong to one of the plurality of signal systems, and

each of the representative light source substrates of the plurality of signal systems is disposed at an end of the row or the column.

5. The video display device according to claim 1, wherein

each of the plurality of light source substrates includes a plurality of connectors that belong to an identical circuit node within a corresponding light source substrate such that the plurality of connectors are respectively disposed at different positions.

6. The video display device according to claim 5, further comprising a plurality of power supply systems, wherein:

each of the plurality of light source substrates includes, as the plurality of connectors, a first power input connector, a second power input connector, a first power output connector, and a second power output connector that belong to an identical power supply node within the corresponding light source substrate,

each of the plurality of light source substrates belongs to any one of the plurality of power supply systems,

the video display device further comprises a power supply substrate that supplies operation power to the plurality of light source substrates,

a first group of the plurality of light source substrates that belong to a first power supply system are connected in series via cable connection provided between the first power output connector and the first power input connector of adjacent ones of the light source substrates, and allow the operation power supplied from the power supply substrate to be transmitted in series between corresponding light source substrates, and

a second group of the plurality of light source substrates that belong to a second power supply system are connected in series via cable connection provided between the second power output connector and the second power input connector of adjacent ones of the light source substrates, and allow the operation power supplied from the power supply substrate to be transmitted in series between corresponding light source substrates.

7. The video display device according to claim 1, wherein

the light emitting diodes and the driver are provided on an identical surface of each of the plurality of light source substrates.

8. The video display device according to claim 2, wherein:

one of the plurality of light source substrates is electrically connected to the signal processing substrate, and

the control signal supplied from the signal processing substrate is input to the one of the plurality of light source substrates, and the signal input to the one light source substrate is distributed to other light source substrates.

9. The video display device according to claim 1, wherein the plurality of light source substrates are physically separated elements from each other.

10. The video display device according to claim 1, wherein the driver is disposed at the vicinity of the each of the plurality of light emitting diodes.