LUMINANCE CORRECTION SYSTEM AND METHOD

• US 20090219306A1
• Filed: 09/12/2008
• Published: 09/03/2009
• Est. Priority Date: 02/28/2008
• Status: Abandoned Application

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Park, Dae-Kil, Oh, Eun-Jung
• Application Number:
  US12/209,982
• Publication Number:
  US 20090219306A1
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2360/147 the originated light output being determined for each pixel
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

A luminance correction system and method include: a data signal application module that applies a data signal to emit light at a maximum luminance; a luminance measurement module that measures luminance of a display region to which the data signal is applied; a comparator that compares luminance with a target value of luminance to obtain a difference value therebetween; a lookup table that adjusts luminance variations of R, G, and B pixels included in the display region by corresponding to the difference value; a data adjustment module that adjusts the data signal depending on the luminance variations of the R, G, and B pixels to transfer it to the data signal applying module; a color coordinate judgment module that judges a color coordinate of the display region; and a chroma correction module that controls chroma corresponding to the color coordinate judged by the color coordinate judgment module.

Claims

1. A luminance correction system comprising:

a data signal application module that applies a data signal to a display region to emit light at a maximum luminance;

a luminance measurement module that measures luminance of a pixel in the display region to which the data signal is applied;

a comparator that compares the measured luminance with a target value of luminance to obtain a difference value therebetween;

a memory that stores a lookup table including luminance variations of R, G, and B pixels in the display region corresponding to the obtained difference value;

a data adjustment module that adjusts the data signal depending on the stored luminance variations of the R, G, and B pixels and transfers the data signal to the data signal application module;

a color coordinate judgment module that judges a color coordinate of the of the R, G, and B pixels; and

a chroma correction module that controls chroma of the R, G, and B pixels corresponding to the color coordinate judged by the color coordinate judgment module.

2. The luminance correction system as claimed in claim 1, wherein the data adjustment module changes a gamma value of the data signal to control the data signal.

3. The luminance correction system as claimed in claim 1, wherein the lookup table stores luminance variations of the R, G, and B pixels corresponding to an entire luminance variations.

4. The luminance correction system as claimed in claim 1, wherein the color coordinate judgment module divides a measured color coordinate into four quadrants and controls chroma of the R, G, and B pixels according to the divided color coordinate.

5. The luminance correction system as claimed in claim 4, wherein the chroma control of the R, G, and B pixels are differently applied depending on whether the measured luminance is higher or lower than the target value.

6. A method for correcting luminance comprising:

measuring luminance of a display region emitting light at a maximum luminance;

comparing the measured luminance with a target value of luminance to calculate a difference value therebetween;

judging luminance variations of a R pixel, a G pixel, and a B pixel corresponding to the calculated difference value;

changing luminance of the R, G, and B pixels depending on the judged luminance variations; and

correcting chroma by selecting one of a plurality of cases of color coordinate of the R, G, and B pixels.

7. The method as claimed in claim 6, wherein judging luminance variations of the respective R, G, and B pixels, utilizes a lookup table.

8. The method as claimed in claim 6, wherein changing the luminance is performed depending on the luminance variations of the respective R, G, and B pixels by adjusting a gamma value.

9. The method as claimed in claim 6, wherein correcting chroma is applied differently depending on whether the measured luminance is higher than the target value or the measured luminance is lower than the target value.

10. A method for correcting luminance in an organic light emitting display having a display region and a plurality of R, G, and B pixels, the method comprising:

applying data signals to cause the display region to emit light;

measuring luminance of the emitted light;

comparing the measured luminance to a target luminance value to determine a difference value;

accessing a lookup table using the difference value to determine luminance variations of a R pixel, a G pixel, and a B pixel in the display region;

changing luminance and chroma of the R, G, and B pixels depending on the determined luminance variations.

11. The method of claim 10 further comprising:

dividing color coordinate of the R, G, and B pixels into four quadrants depending on the measured white color coordinate of the R, G, and B pixels; and

correcting chroma of the R, G, and B pixels by selecting one of the four quadrants of color coordinate of the R, G, and B pixels.