Granted Patent B2

US 12,339,560 · App. 18/620,335 · Granted Jun 24, 2025

Inventors: Craig Lin (Fremont, CA); Haiyan Gu (Fremont, CA)

Assignee: E Ink Corporation

G02F1/1685G02F1/167G02F2203/30

Abstract

Claims (22)

1. A display pixel drive circuit for an electro-optic display, comprising:

an electrophoretic display medium disposed between a first common electrode and a display pixel electrode associated with a display pixel;

a storage capacitor coupled to the display pixel electrode at a first terminal of the storage capacitor; and

a second common electrode coupled to a second terminal of the storage capacitor, wherein the first common electrode and the second common electrode are configured to be set to a non-zero DC bias voltage, a zero volt bias voltage, or a floating state independent of one another,

wherein the pixel drive circuit is configured to discharge the display pixel electrode after a waveform driving sequence by discharging the storage capacitor through the second common electrode by applying a constant voltage set to zero volts to the second common electrode while the display pixel electrode and the first common electrode are in a floating state.

2. The display pixel drive circuit of claim 1 further comprising a transistor associated with the display pixel electrode.

3. The display pixel drive circuit of claim 1 wherein the first common electrode and the second common electrode are configured to receive the same voltage during the waveform driving sequence.

4. The display pixel drive circuit of claim 1 wherein the first common electrode comprises a planar conductive material.

5. The display pixel drive circuit of claim 1 wherein the second common electrode comprises a V COM line signal.

6. An electro-optic display comprising:

an electrophoretic display medium disposed between a first common electrode and a display pixel electrode associated with a display pixel;

a storage capacitor coupled to the display pixel electrode at a first terminal of the storage capacitor;

a second common electrode coupled to a second terminal of the storage capacitor; and

a driver circuit in electrical communication with the first common electrode, the second common electrode, and a transistor associated with the display pixel electrode,

wherein the driver circuit is capable of applying a driving waveform sequence to the display pixel by applying one or more time-dependent voltages between the first common electrode and the display pixel electrode via the transistor, and

wherein the driver circuit is configured to discharge the display pixel electrode after the waveform driving sequence by discharging the storage capacitor through the second common electrode by applying a constant voltage set to zero volts to the second common electrode while the display pixel electrode and the first common electrode are in a floating state.

7. The electro-optic display of claim 6 wherein the driver circuit is configured to control the first common electrode and the second common electrode separately to a non-zero DC bias voltage, a zero volt bias voltage, or a floating state.

8. The display pixel drive circuit of claim 6 wherein the driver circuit is configured to set the first common electrode and the second common electrode to the same voltage during the waveform driving sequence.

9. The display pixel drive circuit of claim 6 wherein the first common electrode comprises a planar conductive material.

10. The display pixel drive circuit of claim 6 wherein the second common electrode comprises a V COM line signal.

11. The electro-optic display of claim 6 wherein the driver circuit is configured to place the first common electrode in a floating state one frame after the display pixel electrode after the driving waveform sequence.

12. The electro-optic display of claim 6 wherein the driver circuit is further configured to place the first common electrode in a floating state one frame prior to the display pixel electrode after the driving waveform sequence.

Assignments (2)

Continuity (4)

References Cited (227)