Industrial Technology Research Institute

Eastman-kodak Company

David M Johnson

Stanley W Stephenson

Robert G Capurso

Xiang-Dong Mi

Domenic Maiola

Charles M Rankin

Theodore K Ricks

Debasis Majumdar

Mitchell Stewart Burberry

Krishnan Chari

Loretta E Allen

Glen C Irvin, Jr

James M Papa

The present invention relates to a bistable matrix-addressable display element comprising a substrate, a bistable electrically modulated imaging layer having a reflection maximum, at least one conductor, and at least one field-spreading layer between said bistable electrically modulated imaging layer and said at least one conductor, wherein said field-spreading layer has a sheet resistance (SER) of less than 10Ohms per square and a method of imaging the display comprising identifying an area to be updated of said bistable matrix-addressable display element, wherein said area to be updated comprises rows of pixels; and applying a sequence of drive signals having a 4-phase approach to image said bistable matrix-addressable display element, which may be characterized as a planar reset, left-slope selection method.

Controlled gap states for liquid crystal displays

A system and method for writing bistable media with a writehead is described. The media has two or more discrete write areas, each area defined by at least one electrical contact, and the media further has at least one alignment feature positioned with regard to one or more discrete write area. The writehead has corresponding alignment features and electrical conductors to the alignment features and electrical contacts of the media.

Indexing writehead for bistable media

A transaction card system includes a transaction card with a display tag for displaying short term information, the character display having optical states that are stable without power and viewable from one side of the display tag and an array of electrical contacts for electrically addressing the character display from the other side of the tag, a contact window through which the contacts are accessible, machine readable data on the card, and a long term information printed on the transaction card; a transaction card writer having a reader for reading the machine readable data and having means for updating the short term information displayed on the transaction card; and a central computer connected to the transaction card writer having a data base and a central processor for receiving the information read by the magnetic card reader and generating display commands for the transaction card writer.

Card with embedded bistable display having short and long term information

A transaction card system includes a transaction cared with a display tag for displaying short term information, the character display having optical states that are stable without power and viewable from one side of the display tag and an array of electrical contacts for electrically addressing the character display from the other side of the tag, a contact window through which the contacts are accessible, machine readable data on the card, and long term information printed on the transaction card; a transaction card writer having a reader for reading the machine readable data and having means for updating the short term information displayed on the transaction card; and a central computer connected to the transaction card writer having a data base and a central processor for receiving the information read by the magnetic card reader and generating display commands for the transaction card writer.

A system and method for writing bistable media is described, wherein the media has at least one through hole that interacts with at least one protrusion on a writer to align the media with the writer.

Writing device for bistable material with improved flexible material alignment features

A display, a signage system including the display, and methods of writing the display, are described, wherein the system includes at least one display, at least one writing unit, and at least one holder. Each display includes at least one bi-stable display element and at least one electrical interconnect substrate. The display can be written using the writing unit and displayed in the writing unit or in the holder.

Electronic signage

A display system includes a display arranged to receive an image wise pattern of light to form an image, including, a pair of conductors, at least one conductor being transparent, a layer of cholesteric liquid crystal material disposed between the conductors, the liquid crystal material having multiple stable optical states at zero electrical field, and a light absorber for forming an image wise thermal pattern in the liquid crystal sufficient to change the optical state of the cholesteric liquid crystal in response to an image wise pattern of light; a display writer, including, a light source for producing a flash of light of sufficient intensity to generate sufficient heat in the light absorber to change the optical state of the cholesteric liquid crystal, a mask located between the light source and the display for defining the image wise pattern of light, a display drive connectable to the conductors for generating an electric field between the conductors for changing the optical state of the cholesteric liquid crystal, and a controller connected to the light source and the display drive for controlling the intensity of the electrical field and actuating the light source to create an image on the display.

Cholesteric liquid crystal display system

The present invention relates to a high contrast reflective display comprising a substrate, at least one electronically modulated imaging layer, wherein the electronically modulated imaging layer comprises a uniformly thick, close-packed, ordered monolayer of domains of electrically modulated material in a fixed polymer matrix, at least one barrier layer, wherein the barrier layer is conductive in a direction perpendicular to the substrate, and at least one electrically conductive layer. The invention also relates to a method of making the display with a barrier layer comprising anisotropic particles and orienting the anisotropic conductor to produce a barrier layer conductive in a direction perpendicular to the substrate.

Displays with low driving voltage and anisotropic particles

A display, a signage system including the display, and methods of writing the display, are described, wherein the system includes at least one looped scroll of bistable display media and at least one electronic writehead. The entire display can be written by using the writehead to address individual sections of the display media by moving the writehead relative to the media.

Scrolling electronic signage

A drive scheme is described for a display capable of gray scale. Multiple two-level pulses are used in conjunction with dynamic relaxation techniques to write pixels ON or OFF and to adjust the gray level of pixels. Only two voltage levels are used, a maximum level U, and a minimum level 0. This reduces the complexity of the electronics so that the only one voltage generator is needed for the display.

Driving scheme for cholesteric liquid crystal display

Apparatus for driving a cholesteric liquid crystal display wherein the display includes cholesteric liquid crystals having a first planar reflective state and a second transparent focal conic state, which is respectively responsive to different applied fields. The apparatus further includes an addressing structure having rows and columns of conductors arranged so that when a column and a row overlap, they define a selectable pixel or segment to be viewable or non-viewable, and a single drive chip responsive to a single input voltage for applying selected voltages to rows and columns of conductors, so that selectable unipolar fields are applied across the cholesteric liquid crystals of the pixels to selectively change the state of the cholesteric liquid crystal.

Unipolar drive chip for cholesteric liquid crystal displays

Apparatus for changing the display state of a bistable liquid crystal display on a display tag having a plurality of electrical contact pads connected to a corresponding plurality of electrodes in the liquid crystal display includes a body defining a slot for receiving and locating the display tag with respect to the body; a plurality of contact pins located in the body and being mounted for movement into the slot to contact the electrical contact pads of a display tag located in the slot; drive electronics electrically connected to the contact pins for receiving display command signals from an external source and for applying electrical drive signals to the electrodes of the display when the contact pins are in contact with the electrical contact pads; and operator control means for moving the contact pins into electrical contact with the electrical contact pads and causing the drive electronics to apply the electrical drive signals to the contact pins.

Write head for a display tag having a liquid crystal display

A display system includes a light writable display associated with an identification code and arranged to receive an image wise pattern of light to form an image on the display; a display writer for producing the image wise pattern of light for writing the image on the display; a scanner connected to the display writer for sensing the identification code; and a processor linked to the scanner and the display writer and responsive to the identification code for programming the display writer to write an image associated with the identification code.

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West Henrietta, NY, United States of America

David M Johnson