E Ink Corporation

Schlumberger Technology Corporation

Services Petroliers Schlumberger

Schlumberger Holdings Limited

Prad Research and Development Limited

Kosta Ladavac

Stephen J Telfer

Christopher L Hoogeboom

Richard J Paolini, Jr

Lee Yezek

Stephen Bull

Craig A Herb

David Darrell Miller

Ana L Lattes

Luke M Slominski

Jennifer M Morrison

Kenneth R Crounse

Sunil Krishna Sainis

Jason D Feick

Michael T Regan

Alain Bouchard

Seth J Bishop

Brandon Ian MacDonald

Crystal Nguyen

J Ryan Kruse

Teck Ping Sim

Peter Carsten Bailey Widger

Oliver Clinton Mullins

Li Jiang

Rogerio Tadeu Ramos

Christopher Harrison

Timothy Gareth John Jones

Bhavani Raghuraman

Ronald E G Van Hal

Jimmy Lawrence

Gale Hyslip Gustavson

Samantha Morrill

Olga Vladimirovna Barykina-Tassa

Andrew A Drabek

Evan Griffith

Olga Vladimirova Barykina-Tassa

Hui Du

Ziyan Wu

Albert Ballard Andrews

Amit Deliwala

Joshua Ritchey

Timothy J O'Malley

Cristina Visani

John Lock

Erik Dunkerley

James H Aborn

Karl Raymond Amundson

George G Harris

Jay William Anseth

Michael D McCreary

Yuval Ben-Dov

Mark Benjamin Romanowsky

Yi Lu

A Ballard Andrews

John L Chuma

Allan Sadun

Brandon Macdonald

Clayton Arroco

Richard J Paolini

Joshua A Ritchey

Jr Richard J Paolini

Michael Thomas Regan

Gale H Gustavson

Ronald EG Van Hal

Electrophoretic displays with multi-particle electrophoretic media and improved methods for driving such multi-particle electrophoretic media, especially using active matrix backplanes and controllers. Larger look-up tables are used, which include a plurality of time-shifted waveforms for each color transition. The controller can thus easily cause a phase shift in the color flashes across the display, which ultimate diminishes or removes the perception that the device is 'flashing' during an update from a first image to a second image. The methods are generalizable to any electrophoretic display using waveforms, and are particularly well-suited for newer multi-particle electrophoretic displays capable of producing four or more colors at each pixel.

Time-shifted waveforms for multi-particle electrophoretic displays providing low-flash image updates

Improved methods for driving a four particle electrophoretic medium including a scattering particle and at least two subtractive particles. Such methods allow displays such as a color electrophoretic display including a backplane having an array of thin film transistors, wherein each thin film transistor includes a layer of metal oxide semiconductor. The metal oxide transistors allow faster, higher voltage switching, and thus allow direct color switching of a four-particle electrophoretic medium without a need for top plane switching. As a result, the color electrophoretic display can be updated faster and the colors are reproduced more reliably.

Driving voltages for advanced color electrophoretic displays and displays with improved driving voltages

Systems and methods are disclosed for pressure-sensitive, electrophoretic displays, which may optionally include haptic feedback. A display may comprise a first conductive layer having a pressure-sensitive conductivity and an electrophoretic layer positioned adjacent to the first conductive layer, wherein the electrophoretic layer is in electrical communication with the first conductive layer and is configured to locally change state based on a pressure applied to the first conductive layer. Local and global writing and erasing of the display can also be achieved.

Pressure-sensitive writing media comprising electrophoretic materials

An electrophoretic display includes an electrophoretic medium having a non-polar fluid and two sets of charged pigment particles dispersed in the non-polar fluid and movable through the non-polar fluid under influence of an electric field. The two sets of charged pigment particles have different optical characteristics from each other. The display also includes a light-transmissive electrode on one side of the electrophoretic medium, a rear electrode on an opposite side of the electrophoretic medium, and a dielectric layer having a dielectric constant greater than 5 between the electrophoretic medium and the light-transmissive electrode or between the electrophoretic medium and the rear electrode configured to reduce electrode electrochemical degradation and buildup of remnant voltages in the display.

Layered structure with high dielectric constant for use with active matrix backplanes

A variable light transmission device has at least one layer of electrophoretic medium comprising charged particles. Application of a an electric field having a waveform formed by a superposition of a carrier and a modulator waveform enables the switching of the device from a closed state to an open state, wherein the open state has higher light transmission than the closed state. As a result, the device enables the selection of the desired optical state by the user.

Driving methods for a variable light transmission device

An electrophoretic display comprising a fluid including a first species of particles and a charge control agent disposed between first and second electrodes. When a first addressing impulse have an electrical polarity is applied to the medium, the first species of particles move in one direction relative to the electric field, but when a second addressing impulse, larger than the first addressing impulse but having the same electrical polarity, is applied to the medium, the first species of particles move in the opposed direction relative to the electric field.

Colored electrophoretic displays using same polarity reversing address pulse

A system for simplified driving of electrophoretic media using a positive and a negative voltage source, where the voltage sources have different magnitudes, and a controller that cycles the top electrode between the two voltage sources and ground while coordinating driving at least two drive electrodes opposed to the top electrode. The resulting system can achieve roughly the same color states as compared to supplying each drive electrode with six independent drive levels and ground. Thus, the system simplifies the required electronics with only marginal loss in color gamut. The system is particularly useful for addressing an electrophoretic medium including four sets of different particles, e.g., wherein three of the particles are colored and subtractive and one of the particles is light-scattering.

Coordinated top electrode—drive electrode voltages for switching optical state of electrophoretic displays using positive and negative voltages of different magnitudes

Improved formulations of electrophoretic media that can be incorporated into displays, front plane laminates, inverted front plane laminates, or color changing films. The formulations include a non-polar fluid, a plurality of first charged particles, and charge control agents (CCA) including a quaternary amine and an unsaturated polymeric tail comprising monomers of at least 10 carbon atoms in length. The formulations show improved switching speeds, as well as a larger dynamic range at low temperatures (i.e., below about 0° C.), where compared to state-of-the-art electrophoretic media.

Electrophoretic media including charge control agents comprising quartenary amines and unsaturated polymeric tails

An electrophoretic medium comprises a fluid, a first, light scattering particle (typically white) and second, third and fourth particles having three subtractive primary colors (typically magenta, cyan and yellow); at least two of these colored particles being non-light scattering. The first and second particles bear polymer coatings such that the electric field required to separate an aggregate formed by the third and the fourth particles is greater than that required to separate an aggregate formed from any other two types of particles. Methods for driving the medium to produce white, black, magenta, cyan, yellow, red, green and blue colors are also described.

Colored electrophoretic displays

A magneto-electrophoretic medium that can be globally and locally addressed and erased. The medium provides a writeable display with no perceivable lag and the ability to write and erase with only minimal power requirements. In particular, the magneto-electrophoretic medium can be erased by providing a subthreshold electric stimulus and supplementing a second non-electric stimulus that disturbs the written state and allows the magneto-electrophoretic particles to return to their original state.

Sub-threshold addressing and erasing in a magneto-electrophoretic writing medium

A method for driving electro-optic displays including electro-optic material disposed between a common electrode and a backplane. The backplane includes an array of pixel electrodes, each coupled to a transistor. A display controller applies waveforms to the pixel electrodes. The method includes applying first measurement waveforms to a first portion of the pixel electrodes. During each frame of the first measurement waveforms, the same time-dependent voltages are applied to each pixel electrode of the first portion of pixel electrodes. The method includes determining the impedance of the electro-optic material in proximity to the first portion of pixel electrodes based on a measurement of the current flowing through a current measurement circuit and the time-dependent voltages applied to each pixel electrode during the first measurement waveforms, and selecting driving waveforms based on the impedance of the electro-optic material in proximity to the first portion of pixel electrodes.

Methods for measuring electrical properties of electro-optic displays

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Somerville, MA, United States of America

Kosta Ladavac