Liquid crystal display and method of driving liquid crystal display

• US 20090135173A1
• Filed: 11/24/2008
• Published: 05/28/2009
• Est. Priority Date: 11/27/2007
• Status: Abandoned Application

• Current Assignee: Funai Electric Co., Ltd.
• Original Assignee: Funai Electric Co., Ltd.
• Inventors: Nakatsuka, Hitoshi
• Application Number:
  US12/313,756
• Publication Number:
  US 20090135173A1
• Time in Patent Office: Days
• US Class Current: 345/212
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• 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 2320/028 by changing the viewing angle properties, e.g. widening the viewing angle, adapting the viewing angle to the view direction
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/2081 with combination of amplitude modulation and time modulation space and time error diffusion G09G3/2066
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

In a liquid crystal display that generates a drive voltage based on input image data corresponding to an image, and applies the drive voltage to a liquid crystal pixel, thereby displaying the image, a plurality of sub-frame data for displaying a plurality of sub-frames are generated. On this occasion, a sub-frame data generation section varies a gray-scale value of the sub-frame data so that luminance values of the sub-frame data are different from each other. Thus, the view angle characteristic can be improved, and the display quality can also be improved.

Claims

1. A liquid crystal display for generating a drive voltage based on input image data, and apply the drive voltage to each pixel of a liquid crystal panel, thereby displaying an image, comprising:

a sub-frame data generation section for generating a plurality of sub-frame data based on each frame datum; and

a drive voltage generation section for executing digital-to-analog conversion on the sub-frame data generated by the sub-frame data generation section, generating the drive voltage based on a signal obtained by the digital-to-analog conversion, and displaying the sub-frame data sequentially in a period for displaying a frame data,

wherein the sub-frame data generation section varies a gray-scale value of each of the sub-frame data so that luminance values of the respective sub-frame data are different from each other.

2. The liquid crystal display according to claim 1, wherein

the sub-frame data generation section generates the sub-frame data so that display periods of the respective sub-frame data are different from each other.

3. The liquid crystal display according to claim 2, wherein

the sub-frame data generation section generates the sub-frame data so that a ratio of the display periods of the respective sub-frame data increases by a factor of 2.

4. The liquid crystal display according to claim 2, wherein

the sub-frame data generation section generates the sub-frame data by combining the display periods and the gray-scale value of the sub-frame data so as to prevent response time of the liquid crystal pixel from becoming insufficient.

5. The liquid crystal display according to claim 1, wherein

the sub-frame data generation section generates the sub-frame data so that the drive voltage has a pulse like waveform with a small signal width.

6. The liquid crystal display according to claim 1, wherein

the sub-frame data generation section generates the sub-frame data by

generating display periods of the sub-frame data different from each other so that a ratio of the display periods of the respective sub-frame data increases by a factor of 2,

varying gray-scale data representing a gray-scale value of the sub-frame data so that the drive voltage has a pulse like waveform with a small signal width, and

combining the display periods and the gray-scale value of the sub-frame data so as to prevent response time of the liquid crystal pixel from becoming insufficient.

7. A method of driving a liquid crystal display that generates a drive voltage based on input image data, and applies the drive voltage to each pixel of a liquid crystal panel, thereby displaying an image, comprising:

generating a plurality of sub-frame data based on each frame data, and in generating the plurality of sub-frame data, making luminance values of the respective sub-frame data different from each other;

executing digital-to-analog conversion on the sub-frame data generated to generate the drive voltage based on a signal obtained by the digital-to-analog conversion; and

displaying the sub-frame data sequentially in a period for displaying a frame data.