Drivers providing dc-balanced refresh sequences for color electrophoretic displays
AssigneeE Ink Corporation
InventorsStephen J. TELFER, Christopher L. HOOGEBOOM, Kenneth R. CROUNSE
Life of this patent
Estimating the term…
Abstract
A method for driving an electro-optic display having a front electrode, a backplane, and a display medium including at least three differently-colored particles, wherein the medium is positioned between the front electrode and the backplane. The method includes applying a DC balance reset phase to first and second pixel electrodes such that the sum of all impulses results in an offset that maintains a DC-balance across the display medium. The invention additionally includes controllers for executing the method.
Claims18
A method for providing a DC balanced reset pulse for an electrophoretic display having a front electrode, a backplane including a first pixel electrode and a second pixel electrode, and a display medium positioned between the front electrode and the backplane, the display medium comprising three sets of differently-colored particles, the method comprising:
- applying a first signal having a first polarity, a first amplitude as a function of time, and a first duration on the front electrode;
- applying no signal during the first duration on the first pixel electrode;
- applying a second signal having a second polarity opposite the first polarity, and a second amplitude as a function of time, during the first duration on the second pixel electrode;
- applying a third signal having the second polarity, and a third amplitude as a function of time, during a second duration on the front electrode;
- applying a fourth signal having the first polarity, and a fourth amplitude as a function of time, during the second duration on the first pixel electrode;
- and
- applying no signal during the second duration on the second pixel electrode.
A controller for an electrophoretic display comprising a front electrode, a backplane including a first pixel electrode and a second pixel electrode, and a display medium positioned between the front electrode and the backplane, the display medium comprising three sets of differently-colored particles, the controller being operatively coupled to the front electrode, the first pixel electrode, and the second pixel electrode, the controller being configured to apply a DC balanced reset pulse to the display,
- the DC balanced reset pulse comprising:
- applying a first signal having a first polarity, a first amplitude as a function of time, and a first duration on the front electrode;
- applying no signal during the first duration on the first pixel electrode;
- applying a second signal having a second polarity opposite the first polarity, and a second amplitude as a function of time, during the first duration on the second pixel electrode;
- applying a third signal having the second polarity, and a third amplitude as a function of time, during a second duration on the front electrode;
- applying a fourth signal having the first polarity, and a fourth amplitude as a function of time, during the second duration on the first pixel electrode;
- and
- applying no signal during the second duration on the second pixel electrode.
Dependencies are inferred from the claim text.