Systems and methods for operating pixels in a display to mitigate image flicker

• US 10,290,284 B2
• Filed: 01/11/2018
• Issued: 05/14/2019
• Est. Priority Date: 05/28/2011
• Status: Active Grant

• Current Assignee: IGNIS Innovation Incorporated
• Original Assignee: IGNIS Innovation Incorporated
• Inventors: Chaji, Gholamreza, Sun Lai, Jackson Chi, Azizi, Yaser, Ma, Maran Ran
• Primary Examiner(s): Adams, Carl
• Application Number:
  US15/868,079
• Publication Number:
  US 20180204541A1
• Time in Patent Office: 488 Days
• Field of Search: None
• CPC Class Codes: G09G 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/0224 Details of interlacing
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/0259 with use of an analog or digital ramp generator in the column driver or in the pixel circuit
• 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 2320/043 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 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 3/3275 Details of drivers for data electrodes
• CPC Class Codes: G09G 5/10 Intensity circuits

Abstract

Circuits for programming a circuit with decreased programming time are provided. Such circuits include a storage device such as a capacitor for storing display information and for ensuring a driving device such as a driving transistor drives a light emitting device according to the display information. The present disclosure provides driving schemes for decreasing flickering perceived while displaying video content by introducing idle phases in between in emission phases to increase the effective refresh rate of a display. Driving schemes are also disclosed for reducing the effects of cross-talk by ensuring that programming information is refreshed in a display array that utilizes a driver connected to multiple data lines via a multiplexer.

Claims

1. A display system comprising:

a plurality of pixels, each including a light emitting device;

a plurality of data lines for conveying programming information to the plurality of pixels;

a source driver for providing the programming information to the data lines via a plurality of data output terminals;

a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines; and

a controller configured to operate the source driver to initiate a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines one at a time to selectively program each pixel with programming information, and to initiate an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein the controller is further configured to operate the source driver to initiate pre-charging cycles to pre-charge a parasitic capacitance of the subset of data lines with respective programming information prior to the subset being selected for programming such that, once selected, the selected pixels programmed via the subset of data lines are programmed according to the voltage programming information charged on the parasitic capacitance of the respective ones of the subset of data lines, and wherein the controller is further configured to operate the source driver, such that the programming of the subset occurs during the pre-charging of the final one of the subset of the plurality of data lines.

2. A display system comprising:

a plurality of pixels, each including a light emitting device;

a plurality of data lines for conveying programming information to the plurality of pixels;

a source driver for providing the programming information to the data lines via a plurality of data output terminals;

a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines; and

a controller configured to operate the source driver to initiate a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines one at a time to selectively program each pixel with programming information, and to initiate an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein the controller is further configured to operate the source driver to initiate pre-charging cycles to pre-charge a parasitic capacitance of the subset of data lines with respective programming information prior to the subset being selected for programming such that, once selected, the selected pixels programmed via the subset of data lines are programmed according to the voltage programming information charged on the parasitic capacitance of the respective ones of the subset of data lines, and wherein a duration of the programming select cycle is equal to a duration of one of the individual pre-charging cycles.

3. A display system comprising:

a plurality of pixels, each including a light emitting device;

a plurality of data lines for conveying programming information to the plurality of pixels;

a source driver for providing the programming information to the data lines via a plurality of data output terminals;

a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines; and

a controller configured to operate the source driver to initiate a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines one at a time to selectively program each pixel with programming information, and to initiate an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein the controller is further configured to operate the source driver to initiate pre-charging cycles to pre-charge a parasitic capacitance of the subset of data lines with respective programming information prior to the subset being selected for programming such that, once selected, the selected pixels programmed via the subset of data lines are programmed according to the voltage programming information charged on the parasitic capacitance of the respective ones of the subset of data lines, and wherein a duration of the programming select cycle is equal to a cumulative duration of all the pre-charging cycles.

4. A display system comprising:

a plurality of pixels, each including a light emitting device;

a plurality of data lines for conveying programming information to the plurality of pixels;

a source driver for providing the programming information to the data lines via a plurality of data output terminals;

a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines;

a controller configured to operate the source driver to initiate a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines one at a time to selectively program each pixel with programming information, and to initiate an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel; and

a plurality of select lines different from said plurality of data lines, one for each of the outputs of the demultiplexer, whereby pixels in a same row are separately selected sequentially to align each selection according to the order of the demultiplexer in providing programming information to the respective data lines.

5. A method of driving a display system comprising a plurality of pixels, a plurality of data lines for conveying programming information to the plurality of pixels, each pixel including a light emitting device, a source driver for providing the programming information to the data lines via a plurality of data output terminals, and a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines, the method comprising:

a) executing a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines, one at a time, to selectively program each pixel with programming information, including

i) sequentially coupling, via one of the demultiplexers, a subset of the plurality of data lines to one of the data output terminals of the source driver to thereby pre-charge respective parasitic capacitances of the subset of the plurality of data lines, and

ii) selecting for programming, via an address driver, pixels coupled to the subset of the plurality of data lines, so as to program the pixels according to the charge stored on the respective parasitic capacitances of the subset of the plurality of data lines; and

b) executing an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein the selecting is initiated during the coupling of the final one of the subset of the plurality of data lines by the demultiplexer.

6. A method of driving a display system comprising a plurality of pixels, a plurality of data lines for conveying programming information to the plurality of pixels, each pixel including a light emitting device, a source driver for providing the programming information to the data lines via a plurality of data output terminals, and a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines, the method comprising:

a) executing a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines, one at a time, to selectively program each pixel with programming information, including

i) sequentially coupling, via one of the demultiplexers, a subset of the plurality of data lines to one of the data output terminals of the source driver to thereby pre-charge respective parasitic capacitances of the subset of the plurality of data lines, and

ii) selecting for programming, via an address driver, pixels coupled to the subset of the plurality of data lines, so as to program the pixels according to the charge stored on the respective parasitic capacitances of the subset of the plurality of data lines; and

b) executing an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein a duration of step a) i) is substantially equal to a duration of pre-charging one of the data lines.

7. A method of driving a display system comprising a plurality of pixels, a plurality of data lines for conveying programming information to the plurality of pixels, each pixel including a light emitting device, a source driver for providing the programming information to the data lines via a plurality of data output terminals, and a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines, the method comprising:

a) executing a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines, one at a time, to selectively program each pixel with programming information, including

i) sequentially coupling, via one of the demultiplexers, a subset of the plurality of data lines to one of the data output terminals of the source driver to thereby pre-charge respective parasitic capacitances of the subset of the plurality of data lines, and

ii) selecting for programming, via an address driver, pixels coupled to the subset of the plurality of data lines, so as to program the pixels according to the charge stored on the respective parasitic capacitances of the subset of the plurality of data lines; and

b) executing an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein a duration step a) i) is substantially equal to a duration of pre-charging all the data lines in the corresponding sub group.

8. A method of driving a display system comprising a plurality of pixels, a plurality of data lines for conveying programming information to the plurality of pixels, each pixel including a light emitting device, a source driver for providing the programming information to the data lines via a plurality of data output terminals, and a plurality of demultiplexers, each demultiplexer including an input coupled to one of data output terminals, and a plurality of outputs for coupling to a different subset of the plurality of data lines, the method comprising:

a) executing a programming select cycle by sequentially coupling each data output terminal to the corresponding subset of data lines, one at a time, to selectively program each pixel with programming information, and

b) executing an emission cycle to emit light from the light emitting devices according to the programming information stored in each pixel, wherein the display further comprises a plurality of select lines different from said plurality of data lines, one for each of the outputs of the demultiplexer, and wherein step a) includes separately selecting and programming pixels in a same row sequentially to align each selection according to the order of the demultiplexer in providing programming information to the respective data lines.