Electrophoretic displays

• US 9,664,978 B2
• Filed: 03/04/2015
• Issued: 05/30/2017
• Est. Priority Date: 10/16/2002
• Status: Expired due to Fees

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Arango, Alexi C., Hertel, Dirk, Amundson, Karl Raymond, Jacobson, Joseph M.
• Primary Examiner(s): Giesy, Adam R
• Application Number:
  US14/638,707
• Publication Number:
  US 20150177589A1
• Time in Patent Office: 818 Days
• Field of Search: None
• CPC Class Codes: B41J 3/4076 printing on rewritable, bistable "electronic paper" by a focused electric or magnetic field
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02F 1/134336 Matrix
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/16757 Microcapsules
• CPC Class Codes: G02F 1/1676 Electrodes
• CPC Class Codes: G02F 1/1681 having two or more microcells partitioned by walls, e.g. of microcup type
• CPC Class Codes: G04B 47/00 Time-pieces combined with other articles which do not interfere with the running or the time-keeping of the time-piece clockwork cases for special purposes G04B37/12; clocks with magnifying glass built in the face G04B39/00; time-pieces in which parts or cases produce special effects, e.g. aesthetic effects, G04B45/00, particularly with inscriptions or pictures moved by hand G04B45/003, with specially shaped cases or parts G04B45/0069; combination of writing or drawing implements with devices for indicating time B43K29/087; combined with cameras, projectors, or photographic printing apparatus G03B29/00
• CPC Class Codes: G06F 15/0283 for data storage and retrieval
• CPC Class Codes: G06K 19/07703 the interface being visual
• CPC Class Codes: G09F 9/302 characterised by the form or geometrical disposition of the individual elements
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 2310/0267 Details of drivers for scan electrodes, other than drivers for liquid crystal, plasma or OLED displays
• CPC Class Codes: G09G 2310/0275 Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
• CPC Class Codes: G09G 3/344 based on particles moving in a fluid or in a gas, e.g. electrophoretic devices electrophoretic devices per se G02F1/167
• CPC Class Codes: G09G 3/3446 with more than two electrodes controlling the modulating element
• CPC Class Codes: H01L 27/12 : the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H05K 1/097 : Inks comprising nanoparticles and specially adapted for being sintered at low temperature H05K1/095 takes precedence
• CPC Class Codes: H05K 3/105 : by conversion of non-conductive material on or in the support into conductive material, e.g. by using an energy beam
• CPC Class Codes: H05K 3/1241 : by ink-jet printing or drawing by dispensing
• CPC Class Codes: H10K 10/46 : Field-effect transistors, e.g. organic thin-film transistors [OTFT] H10K10/43 takes precedence
• CPC Class Codes: H10K 10/462 : Insulated gate field-effect transistors [IGFETs]
• CPC Class Codes: H10K 19/00 : Integrated devices, or assemblies of multiple devices, comprising at least one organic element specially adapted for rectifying, amplifying, oscillating or switching, covered by group H10K10/00
• CPC Class Codes: H10K 85/113 : Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
• CPC Class Codes: H10K 85/114 : Poly-phenylenevinylene; Derivatives thereof
• CPC Class Codes: H10K 85/20 : Carbon compounds, e.g. carbon nanotubes or fullerenes
• CPC Class Codes: H10K 85/30 : Coordination compounds
• CPC Class Codes: H10K 85/311 : Phthalocyanine
• CPC Class Codes: H10K 85/60 : Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence
• CPC Class Codes: H10K 85/611 : Charge transfer complexes
• CPC Class Codes: H10K 85/615 : Polycyclic condensed aromatic hydrocarbons, e.g. anthracene

Abstract

A dielectrophoretic display comprises a substrate having walls defining at least one cavity, the cavity having a viewing surface and a side wall inclined to the viewing surface; a suspending fluid contained within the cavity; a plurality of at least one type of particle suspended within the suspending fluid; and means for applying to the fluid an electric field effective to cause dielectrophoretic movement of the particles to the side wall of the cavity.

Claims

1. A display comprising:

a substrate having walls defining at least one cavity, the cavity having a viewing surface, a rear surface on the opposed side of the cavity from the viewing surface, and at least one side wall extending between the viewing surface and the rear surface;

a colored fluid contained within the cavity;

a plurality of electrically charged solid particles within the fluid;

a front electrode adjacent the viewing surface of the cavity;

a rear electrode adjacent the rear surface; and

a side electrode adjacent the side wall,

the display having a first optical state in which the solid particles lie adjacent the front electrode, a second optical state in which the solid particles lie adjacent the rear electrode and a third optical state in which the solid particles lie adjacent the side electrode.

2. A display according to claim 1 wherein the solid particles are white in color.

3. A display according to claim 1 wherein the cavity has a non-circular cross-section as seen from the viewing surface.

4. A display according to claim 3 wherein the cavity has a polygonal cross-section as seen from the viewing surface.

5. A display according to claim 1 wherein the substrate comprises a substantially rigid material having the at least one cavity formed therein, the substrate further comprising at least one cover member closing the at least one cavity.

6. A display according to claim 1 arranged to have light projected on to a surface on the opposed side of the display from the viewing surface.

7. A process for operating a display, the process comprising:

providing a substrate having walls defining at least one cavity, the cavity having a viewing surface, a rear surface on the opposed side of the cavity from the viewing surface, and at least one side wall extending between the viewing surface and the rear surface;

a colored fluid contained within the cavity;

a plurality of electrically charged solid particles within the fluid;

a front electrode adjacent the viewing surface of the cavity;

a rear electrode adjacent the rear surface; and

a side electrode adjacent the side wall; and

applying to the front, rear and side electrodes electrical potentials effective to cause the solid particles fluid to assume;

(a) a first position in which the solid particles lie adjacent the front electrode, and the display shows a first optical state;

(b) a second position in which the solid particles lie adjacent the rear electrode and the display shows a second optical state; and

(c) a third position in which the solid particles lie adjacent the side electrode and the display shows a third optical state.

8. A process according to claim 7 wherein the solid particles are white in color.

9. A process according to claim 7 wherein the cavity has a non-circular cross-section as seen from the viewing surface.

10. A process according to claim 9 wherein the cavity has a polygonal cross-section as seen from the viewing surface.

11. A process according to claim 7 wherein the substrate comprises a substantially rigid material having the at least one cavity formed therein, the substrate further comprising at least one cover member closing the at least one cavity.

12. A process according to claim 7 further comprising projecting light on to a surface on the opposed side of the display from the viewing surface.