Abstract: A large-area switchable electro-optic light modulator or display and method of manufacture are disclosed. The large-area light modulator comprises an array of individual light modulator units sandwiched between two larger light-transmissive substrates coated on their inner surfaces with light-transmissive electrode layers with electrical connections to each unit that do not compromise the transparency of the light modulator in an open state. The large-area display comprises an array of individual display units. A large-area light-transmissive substrate coated on its inner surface with a light-transmissive electrode layer is superposed on the individual display units with electrical connections to each unit that do not compromise the transparency of the display. The light modulator and the display can be readily manufactured using conventional equipment.

Abstract: 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.

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 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.

Abstract: An electro-optic device is disclosed that comprises an electrophoretic medium including electrically charged pigment particles, a charge control agent, an organic electroactive compound, and a non-polar liquid. The electrophoretic medium is included in a plurality of microcells. The composition of the electrophoretic medium enables the reduction of remnant voltage of the electro-optic device and the degradation of the electrodes and other components of the device even after operation using DC-imbalance waveform.

Abstract: 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.

Abstract: Improved methods for driving an active matrix of pixel electrodes controlled with thin film transistors when the voltage on a top electrode is being altered between driving frames. The method is useful for electrowetting devices. In particular, the methods can provide for more consistent droplet movement when used with a digital microfluidic device based upon an active matrix of pixel electrodes.

Abstract: An electro-optic display comprising at least two separate layers of electro-optic material, with one of these layers being capable of displaying at least one optical state which cannot be displayed by the other layer. The display is driven by a single set of electrodes between which both layers are sandwiched, the two layers being controllable at least partially independently of one another. Another form of the invention uses three different types of particles within a single electrophoretic layer, with the three types of particles being arranged to shutter independently of one another.

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: Mixtures are disclosed containing a plurality of charged pigment particles and a one or more charge control agents. At least one of the charge control agents has a chemical structure that includes a cationic head group, such as an ammonium cation or an iminium compound, and a non-ionic, polar functional group, other than an acyclic secondary amide group. The mixtures are useful as dispersions for forming electrophoretic media that may be incorporated into electrophoretic displays. Alternatively, the dispersions may be useful for forming electrophotographic toners and dispersions for other printing applications.

Abstract: An active molecule delivery system whereby active molecules can be released on demand and/or a variety of different active molecules can be delivered from the same system and/or different concentrations of active molecules can be delivered from the same system. The invention is well-suited for delivering pharmaceuticals to patients transdermally. In some embodiments, the system includes two separate reservoirs and a mixing area thereby allowing precursors to be mixed immediately before transdermal delivery.

Abstract: Electrophoretic displays with multi-particle electrophoretic media and improved methods for driving such multi-particle electrophoretic media, especially using active matrix backplanes and controllers. The driving methods use faster gate updates with differential gaps between set of gate updates for a given pixel. The methods are generalizable to any electrophoretic display using push-pull waveforms, and are particularly well-suited for newer multi-particle electrophoretic displays capable of producing four or more colors at each pixel. Using such methods, electrophoretic displays will appear less “flashy” than addressing with conventional row-by-row constant-frame-spacing updating.

Abstract: A color electrophoretic display with improved black optical state includes an electrophoretic medium having five types of charged electrophoretic pigment particles in a non-polar fluid: a first particle having a first optical property and first charge polarity; a second particle having a second optical property and second opposite charge polarity with a first charge magnitude; a third particle having a third optical property and second charge polarity with a second charge magnitude smaller than the first charge; a fourth particle having a fourth optical property and second charge polarity with a third charge magnitude smaller than the second charge; and a fifth particle having a fifth optical property and second charge polarity with a fourth charge magnitude greater than the first charge. The first and fifth particles are white and black, respectively, and the second, third, and fourth particles are each a different one of cyan, magenta, and yellow.

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 color electrophoretic display includes a light-transmissive electrode at a viewing surface, a back electrode, and an electrophoretic medium disposed therebetween. The electrophoretic medium includes a non-polar fluid and a multi-pigment particle system having four types of charged electrophoretic pigment particles in the fluid. The particles includes first, second, third, and fourth types of particles having different optical properties. The second, third, and fourth types of particles have a charge polarity opposite to the charge polarity of the first type of particle. The multi-pigment particle system is directly addressable with push-pull waveforms applied to the back electrode having voltage levels selected from a set of exactly four different voltage levels to render any of eight primary colors (red, green, blue, cyan, magenta, yellow, black, and white) at each pixel while holding the voltage on the light-transmissive electrode constant.

Abstract: An electro-optic display comprising at least two separate layers of electro-optic material, with one of these layers being capable of displaying at least one optical state which cannot be displayed by the other layer. The display is driven by a single set of electrodes between which both layers are sandwiched, the two layers being controllable at least partially independently of one another. Another form of the invention uses three different types of particles within a single electrophoretic layer, with the three types of particles being arranged to shutter independently of one another.

Abstract: 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.

Abstract: An image is formed on an architectural surface by applying to the surface, in order: a rear electrode layer; a light-transmissive front electrode layer; a photoconductive layer disposed between the front and rear electrode layers; and an electro-optic layer disposed between the front and rear electrode layers. A potential difference is applied between the front and rear electrode layers and the front electrode layer is imagewise exposed to radiation which causes a change in the conductivity of the photoconductive layer, thereby causing an imagewise change in the optical state of the electro-optic layer. Films for application to architectural surfaces are also provided.

Abstract: An electro-optic device comprises in order, an electrically-conductive light-transmissive layer, an electro-optic material layer, an adhesive layer, and a backplane substrate comprising a plurality of pixel electrodes configured to apply an electrical potential between the electrically-conductive light-transmissive layer and the pixel electrodes. An activation region, comprising an identification marker, is located in a layer of the electro-optic device and it emits radiation of a characteristic wavelength upon activation by a stimulus, enabling the identification of the manufacturing source and the manufacturing lot of the electro-optic device and its components. The technology is also relevant for a front plane laminate and a double release sheet, which are useful components for the manufacture of electro-optic devices.

Abstract: A capsule comprising a capsule wall and an electrophoretic fluid encapsulated by the capsule wall. The capsule wall comprises a cross-linked nonionic, water-soluble or water-dispersible polymer. The electrophoretic fluid comprises a suspending fluid, first pigment particles, second pigment particles, and third pigment particles. In some embodiments, the electrophoretic fluid includes a fourth electrophoretic particle. The first, second, and third particles are electrically charged, suspended in the suspending fluid, and capable of moving through the suspending fluid upon application of an electric field to the capsule.