Abstract: A first display comprises a layer of electro-optic material with first and second electrodes on opposed sides thereof, at least one electrode. One or both electrodes having at least two spaced contacts, and voltage control means are arranged to vary the potential difference between the two spaced contacts attached to the same electrode. A second display comprises a layer of electro-optic material with a sequence of at least three electrodes adjacent thereto. Voltage control means vary the potential difference between the first and last electrodes of the sequence. The electrodes of the sequence alternate between the two surfaces of the layer of electro-optic material, and have edges which overlap with or lie adjacent the preceding and following electrodes of the sequence. The electrodes, other than the first and last, are electrically isolated such that the potential thereof is controlled by passage of current through the layer of electro-optic material.

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 multi-color display device has front and rear electrodes on opposed sides of an electrophoretic medium. One of the front and rear electrodes occupies only a minor proportion of a pixel. The device has a voltage control capable of applying a first and a smaller second potential difference of either polarity between the electrodes. The electrophoretic medium has first and second species of particles of differing colors and charge polarities. The first and second particles move independently of one another in response to the first potential difference, but upon application of the second potential difference form charged aggregates, moving as a unit, having an aggregate color different from the first and second colors.

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: 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: 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: The present invention provides for an electro-optic display having a backplane assembly with at least two electrode layers, a first electrode layer of a first dimension electrically connected to and driving a second electrode layer of a second dimension that is larger than the first dimension. The second electrode layer overlies the first electrode layer, such that the entire viewing area of an electro-optic display may be optically-active. The backplane assembly may have at least one interposer layer disposed between the two electrode layers to electrically connect the first and second electrode layers.

Abstract: Polymer shells similar to those described in U.S. Pat. No. 6,822,782 can be formed on pigment particles by (a) physi-sorping a reagent comprising polymerizable groups on to the pigment particles by treating the particle with a reagent having a polymerizable or polymerization-initiating group, such that the reagent will not desorb from the particle surface when the particle is placed in a hydrocarbon medium; or (b) treating pigment particles bearing nucleophilic groups with a reagent having a polymerizable or polymerization-initiating group, and an electrophilic group, thus attaching the polymerizable or polymerization-initiating groups to the particle surface. The zeta potential of the pigment particles can be varied by a process similar to (b) but using a reagent which does not have a polymerizable or polymerization-initiating group.

Abstract: An electro-optic display containing a two-phase, light-transmissive electrically-conductive layer comprising a first phase made of a highly electronically-conductive matrix and a second phase made of a polymeric material composition having a controlled volume resistivity. The matrix of the first phase may be formed from carbon nanotubes, silver nanowires, a metal coated open foam structure, or a printed mesh of wires. The polymeric material composition of the second phase may be a conductive polymer, or a polymer and an additive such as a salt, a polyelectrolyte, a polymer electrolyte, or a solid electrolyte, or combinations thereof.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

Abstract: An electro-optic display has a viewing surface through which a user views the display, a bistable, non-electrochromic electro-optic medium, and at least one electrode arranged to apply an electric field to the electro-optic medium, the display. The display comprises at least 10 micromoles per square meter of the viewing surface of at least one redox compound having an oxidation potential more negative that about 150 mV with respect to a standard hydrogen electrode, as measured at pH 8.

Abstract: A color filter array or a backplane for a color display has first and second areas with substantially different optical properties. The invention also provides a color filter with a low resistivity. The invention further provides a color display utilizing fluorescent or phosphorescent material.

Abstract: An electrophoretic medium comprises a fluid and at least one species of particles disposed, When a first addressing impulse 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, is applied to the medium, the first species of particles move in the opposed direction relative to the electric field.

Abstract: A tetrachromatic color filter array comprises multiple pixels, each of which comprises first, second, third and fourth sub-pixels having first, second, third and fourth hues, P1, P2, P3 and P4 respectively, these first, second, third and fourth hues having first, second and third hue angles, h1, h2, h3 and h4 respectively. The hues of the sub-pixels such that h3 equals h1+(180°±10°) and h4 equals h2+(180°±10°) in the a*b* plane of the La*b* color space.

Abstract: Methods for driving electro-optic displays, especially bistable displays, include (a) using two-part waveforms, the first part of which is dependent only upon the initial state of the relevant pixel; (b) measuring the response of each individual pixel and storing for each pixel data indicating which of a set of standard drive schemes are to be used for that pixel; (c) for at least one transition in a drive scheme, applying multiple different waveforms to pixels on a random basis; and (d) when updating a limited area of the display, driving “extra” pixels in an edge elimination region to avoid edge effects.

Abstract: An electrophoretic display (100) has stacked first (104) and second (120) electrophoretic layers, each comprising charged particles (W, C, Y, M) in a fluid (106, 122). The first layer contains particles of white (W) and first color (M) particles and has three optical states (a) white particles adjacent a viewing surface; (b) first color particles lie adjacent the viewing surface; and (c) both types of particles shuttered to allow light to pass through the first layer. The second layer contains particles having second (C) and third (Y) colors and has three optical states (d) second particles (C) adjacent the first layer; (e) third particles (Y) adjacent the first layer; and (f) second (C) and third (Y) particles intermixed within the fluid.

Abstract: A multicolor direct thermal imaging method wherein a multicolor image is formed in a thermal imaging member comprising at least first and second different image-forming compositions and a thermal printer for use in practicing the method. Heat is applied to at least the second image-forming composition while the first image-forming composition is at a first baseline temperature (T1) to form an image in at least the second image-forming composition, and heat is applied to at least the first image-forming composition while it is at a second baseline temperature (T2) to form an image in at least the first image-forming composition, wherein T1 is different from T2.

Abstract: There are described thermal imaging members and thermal imaging methods utilizing unsymmetrical rhodamine compounds. The rhodamine color-forming compounds exhibit a first color when in a crystalline form and a second color, different from the first color, when in an amorphous form.

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 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.