Display device having a plurality of regions and method of driving the same at different of frequencies

• US 9,633,608 B2
• Filed: 04/09/2014
• Issued: 04/25/2017
• Est. Priority Date: 12/16/2013
• Status: Expired due to Fees

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Shin, Yong Hwan
• Primary Examiner(s): Lao, Lun-Yi
• Assistant Examiner(s): DEADERICK, ELLIOTT J
• Application Number:
  US14/249,141
• Publication Number:
  US 20150170607A1
• Time in Patent Office: 1,112 Days
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2330/022 in absence of operation, e.g. no data being entered during a predetermined time
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/344 based on particles moving in a fluid or in a gas, e.g. electrophoretic devices electrophoretic devices per se G02F1/167
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

In one aspect, the display device includes a display panel including a first region and a second region, wherein the first region is configured to display a first image having a first luminance and wherein the second region is configured to display a second image having a second luminance. The display device also includes a panel driver configured to drive the first region at a first frequency and the second region at a second frequency less than the first frequency and a luminance compensator configured to compensate for the difference between the first and second luminances.

Claims

1. A display device, comprising:

a display panel comprising a first region including a first plurality of pixels and a second region including a second plurality of pixels, wherein the first region is configured to display a first image having a first luminance and wherein the second region is configured to display a second image having a second luminance, wherein the first image is a moving-image and the second image is a still-image;

a panel driver configured to drive the first region at a first frequency and the second region at a second frequency less than the first frequency, wherein the panel driver is configured to respectively apply first and second data voltages to the first plurality of pixels of the first region and the second plurality of pixels of the second region, respectively, wherein the second data voltages are configured to be discharged over time; and

a luminance compensator configured to compensate for the difference between the first and second luminance, wherein the luminance compensator is configured to reduce the first data voltages applied to the first plurality of pixels over a single frame period of the second frequency such that the average of the first data voltages is substantially the same as the average of the second data voltages and such that the first data voltages correspond to the average of the discharge of the second data voltages.

2. The display device of claim 1, further comprising a memory storing a plurality of lookup tables (LUTs) comprising correction data for the first region.

3. The display device of claim 1, further comprising a luminance measurement unit configured to measure luminance of the display panel and output a luminance signal corresponding to the measured luminance to the luminance compensator, wherein the luminance compensator is further configured to compensate for the difference in the luminances based at least in part on the luminance signal.

4. The display device of claim 3, further comprising:

a light source configured to provide light to the display panel; and

a light source driver configured to control the light source,

wherein the luminance compensator is further configured to provide a light source control signal to the light source driver,

wherein the waveform of the light source control signal is substantially symmetrical with respect to the waveform of the luminance signal, and

wherein the light source driver is further configured to drive the light source based at least in part on the light source control signal.

5. The display device of claim 1, further comprising an image controller configured to:

receive present frame image data and previous frame image data;

compare the present frame image data to the previous frame image data; and

set the first region and the second region in the display panel based at least in part on the comparison.

6. The display device of claim 1, wherein the first frequency is about 60 Hz and the second frequency is about 20 Hz.

7. A display device, comprising:

a plurality of pixels comprising a first pixel group and a second pixel group, wherein the first pixel group is configured to display a first image having a first luminance and wherein the second pixel group is configured to display a second image having a second luminance, wherein at least one of the pixels in the first pixel group is configured to display a moving-image and wherein at least one of the pixels in the second pixel group is configured to display a still-image;

a plurality of scan lines electrically connected to the pixels;

a plurality of data lines crossing the scan lines and electrically connected to the pixels;

a scan driver configured to respectively apply a plurality of scan signals to the scan lines and drive the first pixel group at a first frequency and the second pixel group at a second frequency;

a data driver configured to respectively apply a plurality of data voltages to the data lines and to respectively apply first and second data voltages to the first and second pixel groups, respectively, wherein the pixels of the second pixel group are configured to discharge over time; and

a luminance compensator configured to compensate for the difference between the first and second luminances and to lower one or more of the first data voltages applied to the first pixel group over a single frame period of the second frequency such that the average of the first data voltages is substantially the same as the average of the second data voltages applied to the second pixel group and the first data voltages correspond to the average of the discharge of the second data voltages applied to the second pixel group.

8. The display device of claim 7, further comprising a light source configured to provide light to the pixels, wherein the luminance compensator is further configured to increase luminance of the light source based at least in part on a decrease in the second luminance.

9. The display device of claim 7, wherein the first frequency is about 60 Hz and the second frequency is about 20 Hz.

10. The display device of claim 7, further comprising an image controller configured to:

receive present frame image data and previous frame image data;

compare the present frame image data to the previous frame image data; and

set the first pixel group and the second pixel group based at least in part on the comparison.

11. A method of driving a display device comprising a display panel including a first region and a second region, the method comprising:

displaying a first image having a first luminance in the first region including a first plurality of pixels, wherein the first image is a moving-image;

displaying a second image having a second luminance in the second region, including a second plurality of pixels, wherein the second image is a still-image;

driving the first region at a first frequency and the second region at a second frequency, wherein the pixels of the second plurality of pixels are configured to discharge over time;

compensating image data for the difference between the first and second luminances, the compensating comprises lowering one or more first data voltages to be applied to the first plurality of pixels over a single frame period of the second frequency such that the average of the first data voltages is substantially the same as the average of one or more second data voltages and the first data voltages correspond to the average of the discharge of the second data voltages applied to the second plurality of pixels;

converting the compensated image data into the first and second data voltages; and

applying the first and second data voltages to the first and second plurality of pixels of the display panel, respectively.

12. The method of claim 11, wherein the display device further comprises a light source, wherein the method further comprises the light source providing light to the display panel, and wherein the compensating comprises increasing luminance of the light source based at least in part on a decrease in the luminance of the second region.

13. The method of claim 11, wherein the first frequency is about 60 Hz and the second frequency is about 20 Hz.