Full color reflective display with multichromatic sub-pixels

• US 8,466,852 B2
• Filed: 04/20/2004
• Issued: 06/18/2013
• Est. Priority Date: 04/10/1998
• Status: Expired due to Fees

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Drzaic, Paul, Wilcox, Russell J.
• Primary Examiner(s): Nguyen, Jimmy H
• Application Number:
  US10/827,745
• Publication Number:
  US 20040263947A1
• Time in Patent Office: 3,346 Days
• Field of Search: 345/107, 345/55, 359/296, 349/86, 349/89, 204/600, 204/602
• US Class Current: 345/55
• CPC Class Codes: B41J 3/4076 printing on rewritable, bistable "electronic paper" by a focused electric or magnetic field
• CPC Class Codes: G02B 26/026 based on the rotation of particles under the influence of an external field, e.g. gyricons, twisting ball displays based on orientable dipolar particles G02F1/172; based on electrophoresis G02F1/167
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 2001/1678 characterised by the composition or particle type
• CPC Class Codes: G02F 2202/28 Adhesive materials or arrangements
• 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 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/2074 using sub-pixels
• 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: 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 85/30 Coordination compounds
• CPC Class Codes: H10K 85/60 Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence

Abstract

A full color, reflective display having superior saturation and brightness is achieved with a novel display element comprising multichromatic elements. In one embodiment a capsule includes more than three species of particles which differ visually. One embodiment of the display employs three sub-pixels, each sub-pixel comprising a capsule including three species of particles which differ visually. Another embodiment of the display employs color filters to provide different visual states to the user. The display element presents a visual display in response to the application of an electrical signal to at least one of the capsules.

Claims

1. An encapsulated electrophoretic display comprising:

a full-color pixel comprising a first addressable sub-pixel and a second sub-pixel independently addressable from the first sub-pixel, wherein the first sub-pixel comprises a first electrophoretic medium comprising first particles in a suspending fluid and the second sub-pixel comprises a second electrophoretic medium comprising second particles in a suspending fluid, at least some of the second particles having a color different from the color of the first particles, each of the first and second sub-pixels being capable of displaying three colors selected from the group consisting of white, black, red, green, blue, cyan, magenta and yellow when addressed, the first sub-pixel being capable of displaying at least one color different from the colors capable of being displayed by the second sub-pixel.

2. The display of claim 1 further comprising a first color filter extending across the first sub-pixel and a second color filter extending across the second sub-pixel.

3. The display of claim 1 wherein the displaying of one color results from lateral migration of at least one of the electrophoretic particles.

4. The display of claim 1 wherein the suspending fluid of each of the first and second electrophoretic media is colored.

5. The display of claim 1 wherein the suspending fluid of each of the first and second electrophoretic media is clear.

6. The display of claim 1 further comprising a third sub-pixel comprising electrophoretic particles, the third sub-pixel being addressable independently of the first sub-pixel and the second sub-pixel, wherein the third sub-pixel comprises a third electrophoretic medium comprising third particles in a suspending fluid, at least some of the third particles having a color different from the colors of the first and second particles, the third sub-pixel being capable of displaying three colors selected from the group consisting of white, black, red, green, blue, cyan, magenta and yellow when addressed, the third sub-pixel being capable of displaying at least one color different from the colors capable of being displayed by the first sub-pixel and at least one color different from the colors capable of being displayed by the second sub-pixel.

7. The display of claim 6 further comprising a first color filter extending across the first sub-pixel, a second color filter extending across the second sub-pixel and a third color filter extending across the third sub-pixel.

8. The display of claim 6 wherein:

(a) the first sub-pixel is capable of displaying white, cyan and red;

(b) the second sub-pixel is capable of displaying white, magenta and green; and

(c) the third sub-pixel is capable of displaying white, yellow and blue.