Abstract: An electro-optic display having a plurality of pixels is driven from a first image to a second image using a first drive scheme, and then from the second image to a third image using a second drive scheme different from the first drive scheme and having at least one impulse differential gray level having an impulse potential different from the corresponding gray level in the first drive scheme. Each pixel which is in an impulse differential gray level in the second image is driven from the second image to the third image using a modified version of the second drive scheme which reduces its impulse differential The subsequent transition from the third image to a fourth image is also conducted using the modified second drive scheme but after a limited number of transitions using the modified second drive scheme, all subsequent transitions are conducted using the unmodified second drive scheme.

Abstract: 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.

Abstract: A light attenuator comprises a cell comprising a first substrate and a second substrate spaced apart from the first substrate. A layer between the substrates contains an electrophoretic ink, a surface of the layer adjacent the second substrate comprising a monolayer of closely packed protrusions projecting into the layer. The protrusions have surfaces defining a plurality of depressions in the volumes there between.

Abstract: The present invention provides for a method of rendering an image on a reflective display wherein each pixel is capable of rendering a limited number of colors, each of which is rendered by predetermined set of waveforms stored in a waveform lookup table. Furthermore, the present invention provides for a method for rendering an image using such colors, having been chosen for optimal color rendition. This invention further provides for rendering a color image formed from a plurality of pixels on a reflective display wherein each pixel has a color selected from the group consisting of at least: red, green, blue, cyan, magenta, yellow, black and white.

Abstract: 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.

Abstract: A display apparatus includes a reflective layer with reflective material. One or more stacks of additional layers are provided on the reflective layer. Each stack has an optically switchable layer. A plurality of switching elements are located on a side of the reflective layer opposite to the one or more stacks or form part of the reflective layer. Each switching element is operable to apply heating to a switchable portion of the optically switchable layer and thereby change an appearance of the switchable portion when viewed from a viewing side of the display apparatus. The apparatus applies the heating by driving an electrical current through the switching element to generate Joule heating in the switching element. The electrical current flows in an electrical circuit including a portion of the reflective layer.

Abstract: 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.

Abstract: An electro-optic device comprising electrophoretic medium including a dispersion of a plurality of particles in a fluid configured to migrate within the fluid in a direction responsive to an applied electric field. The plurality of particles include a first type of particles having a first charge of a first charge polarity, a second type of particles having a second charge of a second charge polarity, and a third type of particles having a third charge of the second charge polarity. The first charge polarity is opposite to the second charge polarity, and the third type of particles are configured to migrate within the fluid in a direction responsive to an applied magnetic field gradient.

Abstract: An adhesive composition comprising a polyurethane and a cationic polymeric dopant or a polymerizable cationic dopant may be used to form one or more adhesive layers of electro-optic assemblies. They enable improved electro-optic performance of the corresponding electro-optic devices even at low temperatures.

Abstract: An electro-optic display includes a display stack having a layer of electro-optic material between a common electrode and an array of pixel electrodes, each associated with a display pixel. A display controller circuit is in electrical communication with the display stack, and is capable of applying waveforms to each display pixel by applying one or more time-dependent voltages between the common electrode and each pixel electrode. A temperature sensor in communication with the display controller circuit is positioned proximate to the display stack. A first plurality of look-up tables includes waveform shape data representing a plurality of shapes of waveforms the display controller circuit is capable of applying to each display pixel, and a second plurality of look-up tables includes voltage amplitude data representing a plurality of voltage amplitudes the display controller circuit is capable of applying to each display pixel to transition its optical state.

Abstract: Methods of making a top-plane connection in an electro-optic device and devices including such connections. A through hole is created through a rear substrate to provide a connection between a conductor coupled to the rear substrate and a light-transmissive conductive layer coupled to a top transparent substrate. The hole is subsequently filled with a top-plane connection material that provides an electrical connection between the conductor and the light-transmissive conductive layer, but does not provide an electrical connection between a separate rear conductive layer and the light-transmissive conductor.

Abstract: The invention provides methods and related apparatuses for driving an electro-optic display having an electrophoretic display medium electrically coupled between a common electrode and a display pixel associated with a display pixel electrode and an n-type transistor electrically coupled to a display controller circuit capable of applying waveforms comprising frames to the display pixel by applying voltages to the common electrode and the display pixel electrode via the n-type transistor. The method includes applying one or more waveforms to the display pixel to drive the electrophoretic display medium in proximity to the display pixel to a first optical state, and discharging a remnant voltage from the electrophoretic display medium utilizing a leakage conduction effect of the n-type transistor. The method can also include maintaining the display pixel in the first optical state for a hold period comprising one or more frames, and placing the display pixel in a floating state.

Abstract: 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.

Abstract: Enhanced push pull driving waveforms for driving a four particle electrophoretic medium including four different types of particles, for example a set of scattering particles and three sets of subtractive particles. Methods for identifying a preferred waveform for a target color state when using a voltage driver having at least five different voltage levels.

Abstract: An electro-optic assembly includes a layer of electro-optic material configured to switch optical states upon application of an electric field and an anisotropically conductive layer having one or more moisture-resistive polymers and a conductive material, the moisture-resistive polymer having a WVTR less than 5 g/(m2*d).

Abstract: A polymeric film includes a plurality of tapered microcells containing a dispersion of a first group and a second group of charged particles. The first group and second group of charged particles having opposite charge polarities. The tapered microcells include a wall and at least a portion of the wall is configured to repel the first group of charged particles. Also provided is a method of making a laminate for an electrophoretic display comprising embossing a plurality of tapered microcells through a layer of polymeric film and into a release sheet to form an embossed film; laminating the embossed film to a layer of conductive material on a protective sheet to form a laminated film; removing the release sheet from the polymeric film to form an opening to an interior of each microcell of the laminated film; filling the microcells with a dispersion fluid; and sealing the microcells.

Abstract: A switchable light modulator device (201, 202, 203, 204, 205) comprises a first substrate (101, 102, 103) and a second substrate (141, 142, 143, 144) with opposite major surfaces spaced apart by one or more polymer structures that each comprise two or more parts and define wall features (21b, 22b, 23b) for a plurality of cavities (111, 112, 113, 114), the cavities sealing a fluid (71, 72, 73, 74) or gel in discrete volumes. Each of the one or more polymer structures comprises a mould part (21, 22, 23) bonded to the first substrate and defining a recess (31, 32, 33), and a cast part (81, 82, 83, 84) filling the recess and bonded to the second substrate and a surface of the recess, the cast part being defined by the surface of the recess and the second substrate replicating the surfaces of both.

Abstract: 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.

Abstract: A fiber capable of switching optical states is provided. The fiber includes a laminate having a first electrode layer, a second electrode layer, and an electro-optic material between the first and second electrode layers, at least one of the first and second electrode layers being light-transmissive and a sheath surrounding the laminate. The fiber may have a ribbon-like structure, i.e. a width that is substantially greater than its thickness. The electro-optic medium may be an encapsulated electrophoretic medium.

Abstract: A light attenuator that provides transparent light states and absorbing dark states for use in selectively controlling light, especially for smart glass applications. The light attenuator includes abutting areas of attenuation and transparency that form a repeat pattern or a quasi-repeat pattern. The attenuating areas are visible when the light attenuator is in the light state, but the repeat pattern is sufficiently large that a viewer looks through the attenuator and sees no haze.