COLOR DISPLAY DEVICE

• US 20070205972A1
• Filed: 12/13/2005
• Published: 09/06/2007
• Est. Priority Date: 12/15/2004
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Asao, Yasufumi, Mori, Hideo, Inaba, Yutaka
• Granted Patent: US 7,629,955 B2
• Time in Patent Office: Days
• US Class Current: 345/88
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general

Abstract

An active matrix display apparatus includes an active matrix display panel comprising a plurality of pixels arranged in a matrix in a row direction and a column direction, each pixel being constituted by a plurality of subpixels; and a drive circuit for applying a voltage to each of the subpixels so that a polarity of the voltage is inverted at a predetermined period in each of a row direction and a column direction. The plurality of subpixels are arranged in the row direction at a period different from half of the predetermined period of polarity inversion of the voltage in the row direction, thus providing flicker-less color display device even when general driver ICs for dot inversion drive are used.

Claims

1. An active matrix display apparatus, comprising:

an active matrix display panel comprising a plurality of pixels arranged in a matrix in a row direction and a column direction, each pixel being constituted by a plurality of subpixels; and

a drive circuit for applying a voltage to each of the subpixels so that a polarity of the voltage is inverted at a predetermined period in each of a row direction and a column direction;

wherein the plurality of subpixels are arranged in the row direction at a period different from half of the predetermined period of polarity inversion of the voltage in the row direction.

2. An apparatus according to claim 1, wherein the half of the predetermined period of polarity inversion of the voltage in the row direction is 3 in terms of the number of subpixels.

3. An apparatus according to claim 2, wherein the period of the subpixel arrangement in the row direction is 2 in terms of the number of subpixels, and one of 2 subpixels in the period is provided with a green color filter and the other subpixel is provided with a magenta color filter.

4. An apparatus according to claim 2, wherein the period of the subpixel arrangement in the row direction is not less than 4 in terms of the number of subpixels, and one of not less than 4 subpixels in the period is provided with a green color filter and not less than 2 other subpixels are provided with a magenta color filter.

5. An apparatus according to claim 2, wherein the period of the subpixel arrangement in the row direction is not less than 5 in terms of the number of subpixels, and

wherein one of not less than 5 subpixels in the period is provided with a green color filter and not less than 2 other subpixels are provided with a magenta color filter, another one subpixel is provided with a red color filter, and more another one subpixel is provided with a blue color filter.

6. An apparatus according to claim 1, wherein the predetermined period of polarity inversion of the voltage in the column direction is 2 rows.

7. An apparatus according to claim 6, wherein subpixel arrangement in a row has the same arrangement pattern as subpixel arrangement in an adjacent row.

8. An apparatus according to claim 6, wherein in a common period of subpixel arrangement and polarity inversion of voltage in the row direction, an odd number of recurring units of subpixel arrangement and an even number of recurring units of polarity inversion of voltage are present, and subpixel arrangement in a row is shifted from subpixel arrangement in an adjacent row by half of the period of subpixel arrangement.

9. An apparatus according to claim 6, wherein in a common period of subpixel arrangement and polarity inversion of voltage in the row direction, an odd number of recurring units of subpixel arrangement and an odd number of recurring units of polarity inversion of voltage are present, and subpixel arrangement in a row is inverted and shifted from subpixel arrangement in an adjacent row by half of the period of subpixel arrangement.

10. A method of driving an active matrix display apparatus, comprising:

a step of driving an active matrix display panel comprising a plurality of pixels arranged in a matrix in a row direction and a column direction, each pixel being constituted by a plurality of subpixels;

by a drive circuit for applying a voltage to each of the subpixels so that a polarity of the voltage is inverted at a predetermined period in each of a row direction and a column direction;

wherein the plurality of subpixels are arranged in the row direction at a period different from half of the predetermined period of polarity inversion of the voltage in the row direction.