E Ink Corporation

Theodore A Sjodin

Karl Raymond Amundson

Demetrious Mark Harrington

Kenneth R Crounse

Robert Waverly Zehner

Matthew J Aprea

Jason Lin

Chia-Chen Su

Timothy J O'Malley

Benjamin Harris Paletsky

Holly G Gates

Yuval Ben-Dov

Timothy J O'Malley, Jr

Michael Patrick Almon

Hugh M Enxing

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.

Methods for driving electro-optic displays

A method of operating an electro-optic display in which an image is scrolled across the display, and in which a clearing bar is provided between two portions of the image being scrolled, the clearing bar scrolling across in display in synchronization with said two portions of the image, the writing of the clearing bar being effected such that every pixel over which the clearing bar passes is rewritten.

Methods for operating electro-optic displays

A touch screen electro-optic display is arranged such that upon a touch being detected on the display surface, the display surface surrounding the touch 'blinks' by being driven to a different optical state, then back to its original state. A second method uses a display having a pen or stylus which can draw lines upon the display. A first line segment is detected and its area updated using a first drive scheme having short waveforms. The area of a second line segment is updated using the first drive scheme. Thereafter, the areas of both line segments are updated using a second drive scheme different from the first drive scheme.

Line segment update method for electro-optic displays

A bistable electro-optic display having a plurality of pixels each of which is capable of displaying at least three optical states, including two extreme optical states, is driven by the method comprising a first drive scheme capable of effecting transitions between all of the gray levels which can be displayed by the pixels; and a second drive scheme which contains only transitions ending at one of the extreme optical states of the pixels.

An electro-optic display uses first and second drive schemes differing from each other, for example a slow gray scale drive scheme and a fast monochrome drive scheme. The display is first driven to a pre-determined transition image using the first drive scheme, then driven to a second image, different from the transition image, using the second drive scheme. The display is thereafter driven to the same transition image using the second drive scheme; and from thence to a third image, different from both the transition image and the second image, using the first drive scheme.

A method is provided for driving electro-optic displays, especially bistable displays, to avoid edge effects when driving a limited area of the display. Pixels in an edge elimination region, at least one pixel wide and substantially surrounding the limited area, are driven from their original gray level to an intermediate gray level, and then back to their original gray level.

An electro-optic display uses first and second drive schemes differing from each other, for example a slow gray scale drive scheme and a fast monochrome drive scheme. The display is first driven to a pre-determined transition image using the first drive scheme, then driven to a second image, different from the transition image, using the second drive scheme. The display is thereafter driven to the same transition image using the second drive scheme; and from then to a third image, different from both the transition image and the second image, using the first drive scheme.

Waveforms for driving electro-optic displays, especially bistable electro-optic displays, are modified by one or more of insertion of at least one balanced pulse pair into a base waveform; excision of at least one balanced pulse pair from the base waveform; and insertion of at least one period of zero voltage into the base waveform. Such modifications permit fine control of gray levels.

Methods and apparatus for driving electro-optic displays

A bistable electro-optic display is updated by writing an image on the display using a first drive scheme capable of driving pixels to multiple gray levels, and thereafter varied using a second drive scheme using only two gray levels, at least one of which is not an extreme optical state of the pixel.

A method and system for applying addressing voltages to pixels of a display involves receiving input data. The input data includes an indication of an addressing voltage impulse to be applied to a pixel via an electrode. One or more voltage sources are selected, to provide the addressing voltage impulse. The one or more voltage sources each have a pre-selected voltage, The selected one or more voltage sources are electrically connected to an electrode to apply the addressing voltage impulse to the pixel. The invention also provides a method of driving an electro-optic display which uses an intermediate image of reduced bit depth, and a method of driving an electro-optic display which uses a limited number of differing drive voltages, with higher voltage pulses being used before lower voltage pulses.

Growing community of inventors

Lexington, MA, United States of America

Theodore A Sjodin