Methods for driving electro-optic displays

US11145261B2 · kind B2 · utility

Assignee

• E Ink Holdings Inc. · TW

Inventors

• Karl R. Amundson · Cambridge, US
• Matthew J. Aprea · Wellesley, US
• Kenneth R. Crounse · Somerville, US
• Demetrious Mark Harrington · Dartmouth, US
• Jason Lin · Malden, US
• Theodore A. Sjodin · Waltham, US
• Chia-Chen Su · San Francisco, US

Key dates

• Filing date: Apr 21, 2020
• Grant date: Oct 12, 2021
• Expiry date: Apr 21, 2040

Classification

• Technology area (CPC G): Physics
• CPC primary: G09G2320/0257
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

A variety of methods for driving electro-optic displays so as to reduce visible artifacts are described. Such methods include (a) applying a first drive scheme to a non-zero minor proportion of the pixels of the display and a second drive scheme to the remaining pixels, the pixels using the first drive scheme being changed at each transition; (b) using two different drive schemes on different groups of pixels so that pixels in differing groups undergoing the same transition will not experience the same waveform; (c) applying either a balanced pulse pair or a top-off pulse to a pixel undergoing a white-to-white transition and lying adjacent a pixel undergoing a visible transition; (d) driving extra pixels where the boundary between a driven and undriven area would otherwise fall along a straight line; and (e) driving a display with both DC balanced and DC imbalanced drive schemes, maintaining an impulse bank value for the DC imbalance and modifying transitions to reduce the impulse bank value.