Signal processing apparatus, liquid crystal apparatus, electronics device and signal processing method

• US 9,001,168 B2
• Filed: 03/08/2013
• Issued: 04/07/2015
• Est. Priority Date: 03/13/2012
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Nishimura, Haruhiko, Wakabayashi, Junichi
• Primary Examiner(s): XAVIER, ANTONIO J
• Application Number:
  US13/790,128
• Publication Number:
  US 20130241967A1
• Time in Patent Office: 760 Days
• Field of Search: None
• US Class Current: 345/694
• CPC Class Codes: G09G 2320/0209 Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

In the case where a gray-scale difference Δ1 between a pixel 110a and a pixel 110b, a gray-scale difference Δ2 between the pixel 110b and a pixel 110c are each larger than a threshold value, and Δ1>Δ2, gray-scale values of the pixels 110a, 110b and 110c are corrected into the gray-scale value of the pixel 110b+Δ1×(1−α), the gray-scale value of the pixel 110c+Δ2×(1−α), and the gray-scale value of the pixel 110c+Δ2×β, respectively (0≦α, β≦0.5). After the correction, a gray-scale different Δ1a between the pixels 110a and 110b, and a gray-scale different Δ2a between the pixels 110b and 110c satisfy the following formulas: Δ1a>Δ1, and Δ2a>Δ2, respectively.

Claims

1. A signal processing apparatus that is used for a liquid crystal apparatus provided with a plurality of pixels, and that processes a signal for controlling gray-scale for display of each of the plurality of pixels, the signal processing apparatus comprising:

a first detection unit configured to, in the case where a first pixel is arranged between a second pixel and a third pixel, the first pixel, the second pixel and the third pixel being pixels among the plurality of pixels, detect a difference between a first gray-scale value corresponding to the first pixel and a second gray-scale value corresponding to the second pixel as a first gray-scale difference;

a second detection unit configured to detect a difference between the first gray-scale value corresponding to the first pixel and a third gray-scale value corresponding to the third pixel as a second gray-scale difference;

a comparison unit configured to compare the first gray-scale difference and the second gray-scale difference; and

a correction unit configured to make correction of at least two of the first gray-scale value, the second gray-scale value and the third gray-scale value such that the first gray-scale difference is reduced to a third gray-scale difference smaller than the first gray-scale difference and the second gray-scale difference is reduced to a fourth gray-scale difference smaller than the second gray-scale difference, and such that the third gray-scale difference is larger than the fourth gray-scale difference when the first gray-scale difference is larger than the second gray-scale difference, and the third gray-scale difference is smaller than the fourth gray-scale difference when the first gray-scale difference is smaller than the second gray-scale difference.

2. The signal processing apparatus of claim 1, wherein the comparison unit performs comparison to determine whether or not each of the first gray-scale difference and the second gray-scale difference is larger than or equal to a threshold value, and the correction unit makes the correction if each of the first gray-scale difference and the second gray-scale difference is larger than or equal to the threshold value.

3. The signal processing apparatus of claim 1, wherein the comparison unit further compares the first gray-scale value, the second gray-scale value and the third gray-scale value, and the correction unit makes the correction if the first gray-scale value>

the second gray-scale value>

the third gray scale value, or the first gray-scale value<

the second gray-scale value<

the third gray scale value.

4. The signal processing apparatus of claim 1, wherein the comparison unit makes the correction on the basis of the second gray-scale difference.

5. An electronic device comprising the signal processing apparatus of claim 4.

6. A liquid crystal apparatus comprising the signal processing apparatus of claim 1.

7. A signal processing apparatus that is used for a liquid crystal apparatus provided with a plurality of pixels, and that processes a signal for controlling gray-scale for display of each of the plurality of pixels, the signal processing apparatus comprising:

a first detection unit configured to, in the case where a first pixel is arranged between a second pixel and a third pixel, the first pixel, the second pixel and the third pixel being pixels among the plurality of pixels, and a first difference between a first gray-scale value corresponding to the first pixel and a second gray-scale value corresponding to the second pixel is larger than or equal to a threshold value, detect the first difference as a first gray-scale difference;

a second detection unit configured to, when a second difference between the first gray-scale value corresponding to the first pixel and a third gray-scale value corresponding to the third pixel is larger than or equal to the threshold value, detect the second difference as a second gray-scale difference;

a comparison unit configured to compare the first gray-scale difference and the second gray-scale difference; and

a correction unit configured to make correction of at least two of the first gray-scale value, the second gray-scale value and the third gray-scale value such that the first gray-scale difference is reduced to a third gray-scale difference smaller than the first gray-scale difference and the second gray-scale difference is reduced to a fourth gray-scale difference smaller than the second gray-scale difference, and such that the third gray-scale difference is larger than the fourth gray-scale difference when the first gray-scale difference is larger than the second gray-scale difference, and the third gray-scale difference is smaller than the fourth gray-scale difference when the first gray-scale difference is smaller than the second gray-scale difference.

8. The signal processing apparatus of claim 7, wherein the comparison unit further compares first gray-scale value, the second gray-scale value and the third gray-scale value, and the correction unit makes the correction if the first gray-scale value>

the second gray-scale value>

the third gray scale value, or the first gray-scale value<

the second gray-scale value<

the third gray scale value.

9. The signal processing apparatus of claim 7, wherein the comparison unit makes the correction on the basis of the second gray-scale difference.

10. A liquid crystal apparatus comprising the signal processing apparatus of claim 7.

11. An electronics device comprising the signal processing apparatus of claim 7.

12. A signal processing method that is used for a liquid crystal apparatus provided with a plurality of pixels, and that processes a signal for controlling gray-scale for display of at each of the plurality of pixels, the signal processing method comprising:

in the case where a first pixel is arranged between a second pixel and a third pixel, the first pixel, the second pixel and the third pixel being pixels among the plurality of pixels, and a first difference between a first gray-scale value corresponding to the first pixel and a second gray-scale value corresponding to the second pixel is larger than or equal to a threshold value, detecting the first difference as a first gray-scale difference;

when a second difference between the first gray-scale value corresponding to the first pixel and a third gray-scale value corresponding to the third pixel is larger than or equal to the threshold value, detecting the second difference as a second gray-scale difference;

comparing the first gray-scale difference and the second gray-scale difference; and

correcting at least two of the first gray-scale value, the second gray-scale value and the third gray-scale value such that the first gray-scale difference is reduced to a third gray-scale difference smaller than the first gray-scale difference and the second gray-scale difference is reduced to a fourth gray-scale difference smaller than the second gray-scale difference, and such that the third gray-scale difference is larger than the fourth gray-scale difference when the first gray-scale difference is larger than the second gray-scale difference, and the third gray-scale difference is smaller than the fourth gray-scale difference when the first gray-scale difference is smaller than the second gray-scale difference.