Method of driving display panel, driving circuit, and display unit

Patent metadata

Field	Value
Publication number	US-10997912-B2
Application number	US-201916423155-A
Country	US
Kind code	B2
Filing date	May 28, 2019
Priority date	Jul 17, 2018
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

A method of driving a display panel includes: correcting a gate-source voltage of a first transistor to cause the gate-source voltage of a first transistor to become closer to a threshold voltage of the first transistor; and writing a signal voltage into a gate of the first transistor by applying a plurality of voltage pulses to a gate of a second transistor. The correcting and the writing are performed in each of pixels of the display panel. The signal voltage corresponds to an image signal. The voltage pulses applied in the writing include a first voltage pulse and a second voltage pulse. The first voltage pulse is applied previous to the second voltage pulse. The second voltage pulse is applied subsequent to the first voltage pulse. A peak value of the first voltage pulse is higher than a peak value of the second voltage pulse.

First claim

What is claimed is:

1. A method of driving a display panel, the display panel including a plurality of pixels, each of the pixels including a light-emitting element and a pixel circuit, the pixel circuit including a first transistor and a second transistor, the first transistor being configured to control an electric current flowing in the light-emitting element, the second transistor being configured to control an application of a voltage to a gate of the first transistor, the method comprising:
correcting a gate-source voltage of the first transistor in a pixel of the plurality of pixels to cause the gate-source voltage of the first transistor to become closer to a threshold voltage of the first transistor; and
writing, after the correcting the gate-source voltage, a signal voltage to the gate of the first transistor in the pixel by applying a plurality of pulses to a gate of the second transistor, wherein the signal voltage corresponds to an image signal, applying a first pulse of the plurality of pulses writes a first voltage pulse to the gate of the first transistor, applying a second pulse of the plurality of pulses writes a second voltage pulse to the gate of the first transistor, the first voltage pulse being written to the gate of the first transistor prior to the second voltage pulse, and a peak value of the first voltage pulse being higher than a peak value of the second voltage pulse.

2. The method according to claim 1 , wherein the peak value of the second voltage pulse is higher than the signal voltage corresponding to the image signal.

3. The method according to claim 2 , wherein the peak value of the second voltage pulse is equal to a sum of the signal voltage corresponding to the image signal and a correction voltage based on an amount of the peak value of the first voltage pulse.

4. The method according to claim 1 , wherein the peak value of the first voltage pulse is higher than a gate voltage of the first transistor of the light-emitting element in a light emission state.

5. The method according to claim 1 , wherein the first voltage pulse is applied to the gate of the first transistor in the writing only when the image signal is at a low gray-scale level.

6. A driving circuit configured to drive a display panel, the display panel including a plurality of pixels, each of the pixels including a light-emitting element and a pixel circuit, the pixel circuit including a first transistor and a second transistor, the first transistor being configured to control an electric current flowing in the light-emitting element, the second transistor being configured to control an application of a voltage to a gate of the first transistor, the driving circuit comprising:
writing circuitry configured to correct a gate-source voltage of the first transistor in a pixel of the plurality of pixels to cause the gate-source voltage to become closer to a threshold voltage of the first transistor, and write, after correcting the gate-source voltage, a signal voltage to the gate of the first transistor in the pixel by applying a plurality of pulses to a gate of the second transistor, wherein the signal voltage corresponds to an image signal, the writing circuitry is configured to write a first voltage pulse during a first pulse of the plurality of pulses and to write a second voltage pulse during a second pulse of the plurality of pulses, the first voltage pulse being applied prior to the second voltage pulse, and a peak value of the first voltage pulse being higher than a peak value of the second voltage pulse.

7. A display unit comprising:
a display panel including a plurality of pixels, each of the pixels including a light emitting element and a pixel circuit, the pixel circuit including a first transistor and a second transistor, the first transistor being configured to control an electric current flowing in the light-emitting element, the second transistor being configured to control an application of a voltage to a gate of the first transistor; and
a driving circuit configured to drive the display panel, the driving circuit being configured to correct a gate-source voltage of the first transistor in a pixel of the plurality of pixels to cause the gate-source voltage to become closer to a threshold voltage of the first transistor, and write, after correcting the gate-source voltage, a signal voltage to the gate of the first transistor in the pixel by applying a plurality of pulses to a gate of the second transistor, wherein the signal voltage corresponds to an image signal, the writing circuitry is configured to write a first voltage pulse during a first pulse of the plurality of pulses and to write a second voltage pulse during a second pulse of the plurality of pulses, the first voltage pulse being applied prior to the second voltage pulse, a peak value of the first voltage pulse being higher than a peak value of the second voltage pulse.

Assignees

• Joled Inc

Inventors

• Ishii Hiroaki
• Hyodo Atsushi
• Isobe Teppei

Classifications

• G09G3/2007

  Display of intermediate tones · CPC title

• G09G3/3233 Primary

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• G09G2310/0202

  Addressing of scan or signal lines · CPC title

• G09G2320/0247

  Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes · CPC title

• G09G2330/028

  Generation of voltages supplied to electrode drivers in a matrix display other than LCD · CPC title