Display device

Patent metadata

Field	Value
Publication number	US-11922869-B2
Application number	US-202217983462-A
Country	US
Kind code	B2
Filing date	Nov 9, 2022
Priority date	Nov 19, 2021
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

A display device including: a display panel including a plurality of pixels; a display panel driver configured to drive the display panel; a memory device configured to store a reference current-temperature model that is set for the display panel, a global offset of the display panel, which is calculated based on the reference current-temperature model in a manufacturing stage of the display panel, and a local offset of the display panel, which is calculated based on a characteristic difference between the pixels in the manufacturing stage; and a panel temperature determiner configured to measure sensing currents flowing through the pixels when a temperature sensing voltage is applied to the pixels, calculate correction sensing currents by applying the global offset and the local offset to the sensing currents, and determine temperatures of the pixels by substituting the correction sensing currents into the reference current-temperature model.

First claim

What is claimed is:

1. A display device, comprising:
a display panel including a plurality of pixels;
a display panel driver configured to drive the display panel;
a memory device configured to store a reference current-temperature model that is set for the display panel, a global offset of the display panel, which is calculated based on the reference current-temperature model in a manufacturing stage of the display panel, and a local offset of the display panel, which is calculated based on a characteristic difference between the pixels in the manufacturing stage; and
a panel temperature determiner configured to measure sensing currents flowing through the pixels when a temperature sensing voltage is applied to the pixels, calculate correction sensing currents by applying the global offset and the local offset to the sensing currents, and determine temperatures of the pixels by substituting the correction sensing currents into the reference current-temperature model,
wherein, in the manufacturing stage, an average temperature of the display panel is measured by a temperature sensing device,
wherein, in the manufacturing stage, initial sensing currents flowing through the pixels when the temperature sensing voltage is applied to the pixels are measured an average of the initial sensing currents is calculated, and a difference between a current mapped to the average temperature in the reference current-temperature model and the average of the initial sensing currents is determined as the global offset.

2. The display device of claim 1 , further comprising:
a temperature afterimage compensator configured to perform temperature afterimage compensation on image data that is to be applied to the pixels based on the temperatures of the pixels.

3. The display device of claim 1 , wherein, in the manufacturing stage, initial sensing currents flowing through the pixels when the temperature sensing voltage is applied to the pixels are measured, an average of the initial sensing currents is calculated, and a difference between each of the initial sensing currents and the average of the initial sensing currents is determined as the local offset.

4. The display device of claim 1 , wherein a frame in which the display panel operates includes an active period and a vertical blank period, and the panel temperature determiner performs a sensing current measurement operation of measuring the sensing currents during the vertical blank period.

5. The display device of claim 4 , wherein the panel temperature determiner performs the sensing current measurement operation for one pixel row during the vertical blank period.

6. The display device of claim 4 , wherein the panel temperature determiner does not perform the sensing current measurement operation during the vertical blank period in a preset low gray level frame.

7. The display device of claim 6 , wherein the panel temperature determiner determines the frame as the preset low gray level frame when iaxi mum gray level of image data of the frame is less than a reference gray level, determines the frame as the preset low gray level frame when a minimum gray level of the image data of the frame is less than the reference gray level, or determines the frame as the preset low gray level frame when an average gray level of the image data of the frame is less than the reference gray level.

8. The display device of claim 4 , wherein the panel temperature determiner performs a panel temperature determination operation of determining the temperatures of the pixels after the sensing current measurement operation for all of the pixels is completed.

9. A display device, comprising:
a display panel including a plurality of pixels, which are grouped into pixel blocks;
a display panel driver configured to drive the display panel;
a memory device configured to store a reference current-temperature model that is set for the display panel, a global offset of the display panel, which is calculated based on the reference current-temperature model in a manufacturing stage of the display panel, and a local offset of the display panel, which is calculated based on a characteristic difference between the pixel blocks in the manufacturing stage; and
a panel temperature determiner configured to measure sensing currents flowing through the pixels when a temperature sensing voltage is applied to the pixels, calculate sensing current averages of the pixel blocks, calculate correction sensing current averages by applying the global offset and the local offset to the sensing current averages, and determine temperatures of the pixel blocks by substituting the correction sensing current averages into the reference current-temperature model,
wherein, in the manufacturing stage, an average temperature of the display panel is measured by a temperature sensing device,
wherein, in the manufacturing stage, initial sensing currents flowing through the pixels when the temperature sensing voltage is applied to the pixels are measured an average of the initial sensing currents is calculated, and a difference between a current mapped to the average temperature in the reference current-temperature model and the average of the initial sensing currents is determined as the global offset.

10. The display device of claim 9 , further comprising:
a temperature afterimage compensator configured to perform temperature afterimage compensation on image data that is to be applied to the pixel blocks based on the temperatures of the pixel blocks.

11. The display device of claim 9 , wherein, in the manufacturing stage, initial sensing currents flowing through the pixels when the temperature sensing voltage is applied to the pixels are measured, an average of the initial sensing currents is calculated, initial sensing current averages of the pixel blocks are calculated, and a difference between each of the initial sensing current averages of the pixel blocks and the average of the initial sensing currents is determined as the local offset.

12. The display device of claim 9 , wherein a frame in which the display panel operates includes an active period and a vertical blank period, and the panel temperature determiner performs a sensing current measurement operation of measuring the sensing currents during the vertical blank period.

13. The display device of claim 12 , wherein the panel temperature determiner performs the sensing current measurement operation for one pixel row during the vertical blank period.

14. The display device of claim 12 , wherein the panel temperature determiner does not perform the sensing current measurement operation during the vertical blank period in a preset low gray level frame.

15. The display device of claim 14 , wherein the panel temperature determiner determines the frame as the preset low gray level frame when a maximum gray level of image data of the frame is less than a reference gray level, determines the frame as the preset low gray level frame when a minimum gray level of the image data of the frame is less than the reference gray level, or determines the frame as the preset low gray level frame when an average gray level of the image data of the frame is less than the reference gray level.

16. The display device of claim 12 , wherein the panel temperature determiner performs a panel temperature determination operation of determining the temperatures of the pixel blocks after the sensing current measurement operation for all of the pixels is completed.

17. A display device, comprising:
a display panel including a plurality of pixels;
a display panel driver con

Assignees

• Samsung Display Co Ltd

Inventors

• Bang Sunghoon
• Ban Seokgyu
• Eun Dong-Ki
• Park Seungho
• Lee Wook

Classifications

• G09G3/3225 Primary

  using an active matrix · CPC title

• G09G2300/0842

  forming a memory circuit, e.g. a dynamic memory with one capacitor · CPC title

• G09G2300/0852

  being a dynamic memory with more than one capacitor · CPC title

• G09G2310/061

  for resetting or blanking · CPC title

• G09G2320/0257

  Reduction of after-image effects · CPC title