Liquid crystal display apparatus

• US 7,233,304 B1
• Filed: 03/22/2000
• Issued: 06/19/2007
• Est. Priority Date: 03/23/1999
• Status: Expired due to Term

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi, Ltd.
• Inventors: Aratani, Sukekazu, Yamamoto, Tsunenori, Kondo, Katsumi, Adachi, Masaya, Hiyama, Ikuo
• Primary Examiner(s): Hjerpe; Richard
• Assistant Examiner(s): Abdulselam; Abbas I.
• Application Number:
  US09/532,740
• Time in Patent Office: 2,645 Days
• Field of Search: 345/102, 345/104, 345/968, 345/3.9, 345/501, 345/536, 345/565, 345/87, 345/84, 349/5, 349/8, 349/62, 313/114, 353/98
• US Class Current: 345/87
• CPC Class Codes: G02F 1/133604 with lamps
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G09G 2300/0434 Flat panel display in which a field is applied parallel to the display plane
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2320/103 Detection of image changes, e.g. determination of an index representative of the image change
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines

Abstract

A liquid crystal display apparatus comprises a liquid crystal display unit including a pair of substrates, at least one of which is transparent, a liquid crystal layer sandwiched by the pair of substrates, a plurality of electrodes for applying an electric field to at least one of the pair of substrates, and a plurality of active elements connected to the plurality of electrodes; a lighting device including a plurality of light sources; and a control unit for controlling ON/OFF of at least one light source for each of regions, into which the lighting device is divided, based on a display response of said liquid crystal display unit.

Claims

1. A liquid crystal display apparatus comprising:

a liquid crystal display unit including a pair of substrates, at least one of which is transparent, a liquid crystal layer sandwiched by said pair of substrates, a plurality of electrodes for applying an electric field to at least one of said pair of substrates, and a plurality of active elements connected to said plurality of electrodes;

a lighting device including a plurality of light sources which is divided into plural regions for illuminating corresponding plural illumination regions of an entirety of a display area of the liquid crystal display unit; and

a control unit for controlling ON and OFF states of a light source for each of the plural regions into which said lighting device is divided, in synchronization with horizontal synchronization signals and vertical synchronization signals, so that the ON state of individual ones of the plural regions of the divided lighting device is shifted among the plural regions, and an individual illumination region of the plural illumination regions of the entirety of the display area of the liquid crystal display unit is correspondingly shifted therewith.

2. A liquid crystal display apparatus according to claim 1, wherein said display response of said liquid crystal display unit is the scanning of the entire liquid crystal display unit.

5. A liquid crystal display apparatus according to one of claims 1 and 3, wherein said light source is a surface emission-type element.

3. A liquid crystal display apparatus comprising:

a liquid crystal display unit for displaying image signals;

a drive unit for driving said liquid crystal display unit;

a lighting device including a light-adjustment unit for adjusting a quantity of light from a light source, which is transmitted to each of plural regions into which the lighting device is divided for illuminating corresponding plural illumination regions of an entirety of a display area of the liquid crystal display unit; and

a control unit for controlling each light-adjustment unit in synchronization with horizontal synchronization signals and vertical synchronization signals, so that the adjusted light quantity of individual ones of the plural regions of the divided lighting device is shifted among the plural regions and an individual illumination region of the plural illumination regions of the entirety of the display area of the liquid crystal display unit is correspondingly shifted therewith.

4. A liquid crystal display apparatus according to claim 3, wherein said light-adjustment unit transmits light when no voltage is applied to said light-adjustment unit.

6. A liquid crystal display apparatus according to claim 3, wherein each region in said lighting device is partitioned with partition plates.

7. A liquid crystal display apparatus according to claim 3, wherein said display response of said liquid crystal display unit is the scanning of the entire liquid crystal display unit.

8. A liquid crystal display apparatus comprising:

a liquid crystal display unit;

a controller for controlling image-displaying performed by said liquid crystal display unit, which includes a determining circuit for determining whether image signals to be displayed on said liquid crystal display unit are for a static image or a dynamic image;

a drive unit for driving said liquid crystal display unit based on a signal sent from said controller;

a lighting device which includes a plurality of light sources, for transmitting light from said plurality of light sources to said liquid crystal display unit; and

a control unit for controlling ON and OFF states of a light source for each of plural regions into which said lighting device is divided, in synchronization with horizontal synchronization signals and vertical synchronization signals, when dynamic images are displayed in accordance with a result in said determination performed by said controller.

9. A liquid crystal display apparatus according to claim 8, wherein said control unit turns on all light sources in said lighting device while a static image is displayed in accordance with a result in said determination of said controller.

10. A liquid crystal display apparatus according to claim 8, wherein a dynamic image display response of said liquid crystal display unit is the scanning of the entire liquid crystal display unit.