External Compensation for Display on Mobile Device

• US 20180075798A1
• Filed: 07/27/2017
• Published: 03/15/2018
• Est. Priority Date: 09/14/2016
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Nho, Hyunwoo, Lin, Hung Sheng, Ryu, Jie Won, Tan, Junhua, Chang, Sun-Il, Gao, Shengkui, Zhang, Rui, Hwang, Injae, Brahma, Kingsuk, Richmond, Jesse Aaron, Shen, Shiping, Kim, Hyunsoo, Knitter, Sebastian, Zhang, Lu, Bonnier, Nicolas P., Yeh, Chih-Wei, Wang, Chaohao, Sacchetto, Paolo, Lin, Chin-Wei, Vahid Far, Mohammad B, Ono, Shinya, Bi, Yafei, Gharghi, Majid, Murugan, Kavinaath, Wang, Yun, Shaeffer, Derek K., Cagdaser, Baris, Jung, Tobias, Albrecht, Marc, Cho, Myung-Je
• Application Number:
  US15/661,995
• Publication Number:
  US 20180075798A1
• Time in Patent Office: Days
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/066 Waveforms comprising a gently increasing or decreasing portion, e.g. ramp
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 2320/029 by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
• CPC Class Codes: G09G 2320/0295 by monitoring each display pixel
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2320/045 Compensation of drifts in the characteristics of light emitting or modulating elements
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• 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 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element

Abstract

A mobile electronic device includes a display having a pixel and processing circuitry separate from but communicatively coupled to the display. The processing circuitry prepares image data to send to the pixel and adjusts the image data to compensate for operational variations of the display based on feedback received from the display that describes a present operational behavior of the pixel. The mobile electronic device also includes additional electronic components that affect the present operational behavior of the pixel depending on present operational behavior of the additional electronic components.

Claims

1. A mobile electronic device comprising:

a display comprising a pixel;

processing circuitry separate from but communicatively coupled to the display, wherein the processing circuitry is configured to prepare image data to send to the pixel and adjust the image data to compensate for operational variations of the display based on feedback received from the display that describes a present operational behavior of the pixel; and

one or more additional electronic components that affect the present operational behavior of the pixel depending on present operational behavior of the one or more additional electronic components.

2. The mobile electronic device of claim 1, wherein the processing circuitry is configured to adjust the image data to compensate for the operational variations of the display by:

generating a compensation value that, when applied to the image data, compensates for the operational variations of the display; and

apply the compensation value to the image data.

3. The mobile electronic device of claim 1, wherein the operational variations comprise aging of the display, degradation of the display, temperature across the display, or any combination thereof.

4. The mobile electronic device of claim 1, wherein display is configured to sense the operational variations when displaying test image data or user image data.

5. The mobile electronic device of claim 1, wherein the display is configured to:

program the pixel with test data; and

sense the operational variations by sensing voltage, current, or a combination thereof, of a response of the pixel to being programmed with the test data.

6. The mobile electronic device of claim 1, wherein the display is configured to reduce noise on a sense line of the display by performing differential sensing, difference-differential sensing, correlated double sampling, programmable capacitor matching, or any combination thereof.

7. The mobile electronic device of claim 1, wherein the processing circuitry is configured to cause the display to turn off and cause the display to modify a gate source voltage of a drive transistor coupled to a light emitting diode of the display while the display is turned off.

8. A method comprising:

sensing, via current sensing, operational variations of an electronic display; and

adjusting, via processing circuitry apart from the electronic display, image data that is sent to the electronic display based at least in part on the operational variations.

9. The method of claim 8, wherein sensing, via the current sensing, the operational variations comprises:

sensing a first parameter of a first pixel of the electronic display; and

sensing a second parameter of a second pixel of the electronic display while the first pixel operates in a non-light emitting mode.

10. The method of claim 9, wherein adjusting, via the processing circuitry, the image data that is sent to the electronic display is based at least in part on sensing the first parameter and sensing the second parameter.

11. The method of claim 8, comprising generating, via the processing circuitry, a correction value based at least in part on a correction curve associated with the pixel.

12. The method of claim 11, wherein adjusting, via the processing circuitry, the image data that is sent to the electronic display is based at least in part on applying the correction value to the image data sent to the electronic display.

13. The method of claim 11, comprising updating, via the processing circuitry, the correction curve based at least in part on the correction value.

14. The method of claim 8, comprising:

filtering, via the processing circuitry, the operational variations to produce correction factors, a correction map, or both; and

sending the correction factors, the correction map, or both, to the electronic display.

15. An electronic device comprising:

a display comprising;

a display panel, wherein the display panel comprises a pixel; and

display driver circuitry comprising integrated display sensing circuitry configured to sense a present operational variation of the pixel; and

processing circuitry communicatively coupled to the display, wherein the processing circuitry is configured to;

receive an indication of the present operational variation of the pixel from the display;

adjust image data based at least in part on the present operational variation of the pixel; and

send the image data to the display.

16. The electronic device of claim 15, wherein the display comprises an analog-to-digital converter configured to digitize the indication of the present operational variation of the pixel before it is sent to the processing circuitry.

17. The electronic device of claim 15, wherein the integrated display sensing circuitry comprises a sensing analog front end configured to perform analog sensing of a response of the pixel to test image data or user image data.

18. The electronic device of claim 15, wherein the processing circuitry is configured to adjust the image data using a dual loop compensation scheme.

19. The electronic device of claim 18, wherein the dual loop compensation scheme comprises a coarse scan loop updated at a first rate and a fine scan loop updated at a second rate, wherein the first rate is faster than the second rate.

20. The electronic device of claim 15, comprising filtering circuitry communicatively coupled to the processing circuitry, wherein the filtering circuitry is configured to filter the operational variations.