Liquid crystal display device

• US 7,961,162 B2
• Filed: 12/06/2006
• Issued: 06/14/2011
• Est. Priority Date: 12/20/2005
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: Kubo, Chikae, Tokuda, Naoki
• Primary Examiner(s): Shalwala; Bipin
• Assistant Examiner(s): BEDELL, DANIEL J
• Application Number:
  US11/634,263
• Publication Number:
  US 20070139341A1
• Time in Patent Office: 1,651 Days
• Field of Search: None
• US Class Current: 345/87
• CPC Class Codes: G09G 2310/0245 Clearing or presetting the whole screen independently of waveforms, e.g. on power-on G09G2310/063 takes precedence
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

In a liquid crystal display device, both of the brightness characteristic and the chromaticity characteristic are set to optimum values. In the liquid crystal display device which includes a liquid crystal display panel, a data driver, a scanning driver and a display control circuit, the display control circuit includes a first circuit which generates insertion display data which differs from the image display data and inserts the display data into the data driver, and a second circuit which sets a first time at which the scanning signal for displaying the display data and a second time at which the scanning signal for displaying the insertion display data are outputted. The first circuit generates display data of one chromatic color and, at the same time, sets gradations of chromatic color for every frame period.

Claims

1. A liquid crystal display device comprising:

a liquid crystal display panel in which a plurality of data signal lines and a plurality of scanning signal lines are arranged in a matrix array and in which a plurality of pixel regions are each formed in a respective region surrounded by two neighboring data signal lines of the plurality of data signal lines and two neighboring scanning signal lines of the plurality of data signal lines;

a data driver which outputs a display signal to the plurality of data signal lines;

a scanning driver which outputs a scanning signal to the plurality of scanning signal lines; and

a display control circuit which controls the scanning driver, wherein

the display control circuit includes;

a first circuit which divides image display data inputted from an external device for each frame period, generates insertion display data for each frame period which differs from the image display data, and transmits the image display data inputted from the external device to the data driver with the insertion display data inserted between the image display data, and

a second circuit which sets a first time at which the scanning signal for displaying the image display data inputted from the external device is outputted to the respective scanning signal lines and a second time at which the scanning signal for displaying the insertion display data is outputted to the respective scanning signal lines, and

wherein the first circuit sets gradations of chromatic color for every frame period when generating the insertion display data,

wherein the first circuit sets the gradations when generating the insertion display data based on an average gradation of the image display data for each frame period, and

wherein the first circuit generates and inserts blue insertion display data between the image display data.

2. A liquid crystal display device according to claim 1, wherein the first circuit increases the gradations of the insertion display data when the average gradation has high gradation data, and decreases the gradation of the insertion display data when the average gradation has low gradation data.