Electronic display with photo-addressing means

• US 7,023,420 B2
• Filed: 11/29/2001
• Issued: 04/04/2006
• Est. Priority Date: 11/29/2000
• Status: Expired due to Fees

• Current Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Original Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Inventors: Comiskey, Barrett, Wilcox, Russell J.
• Primary Examiner(s): NGUYEN, CHANH DUY
• Application Number:
  US09/683,179
• Publication Number:
  US 20020063661A1
• Time in Patent Office: 1,587 Days
• Field of Search: 345/105, 345/106, 345/107, 345/48, 345/49, 345/50, 345/51, 345/55, 345/76, 345/77, 345/82, 345/87, 345/88, 345/63, 345/72
• US Class Current: 345/107
• 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 2201/12 electrode
• 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 2310/02 Addressing, scanning or driving the display screen or processing steps related thereto
• CPC Class Codes: G09G 2310/0221 with use of split matrices G09G3/3644 and G09G3/3666 take precedence
• CPC Class Codes: G09G 3/02 by tracing or scanning a light beam on a screen
• 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

Abstract

An electronic display comprises an electro-optic material (preferably an electrophoretic medium) having a plurality of pixels, and separate first, second and third sets of addressing means for addressing these pixels. Each of the pixels is associated with one addressing means in each of the three sets, such that addressing of any specific pixel requires application of signals within predetermined ranges to each of the three addressing means associated with the specific pixel being addressed.

Claims

1. An electronic display comprising an electro-optic material having a plurality of pixels, and separate first, second and third sets of addressing means for addressing said pixels, each of said pixels being associated with one addressing means in each of said three sets, such that any specific pixel of the display can be addressed by application of signals within predetermined ranges to each of the three addressing means associated with said specific pixel, wherein at least one of the sets of addressing means comprises a photoconductor, the display further comprising (a) a plurality of light sources associated with the photoconductor and selectively operable to switch the photoconductor between a conductive and a non-conductive state, the light sources being arranged as a series of elongate rows, each elongate row defining at least one row of pixels of the display:

and (b) light valves disposed between the light sources and the photoconductor and arranged to control transmission of light from the light sources to the photoconductor.

2. An electronic display according to claim 1 wherein the pixels are arranged in a plurality of sub-arrays, each pixel within any specific sub-array being associated with one of the first and second sets of addressing means, the third set of addressing means having the form of a plurality of switching means, at least one of said switching means being associated with each of said sub-arrays, the switching means associated with each sub-array having an off state, in which signals on at least one of the first and second sets of addressing means are prevented from reaching the associated sub-array, and an on state, in which signals from both the first and second sets of addressing means are permitted to reach and address the associated sub-array.

3. An electronic display according to claim 2 further comprising control means arranged to control the switching means so that only the switching means associated with one sub-array is in its on state at any given moment.

4. An electronic display according to claim 2 wherein each sub-array comprises a discrete page, the pages formed by the plurality of sub-arrays being stacked on top of each other so that the entire display forms a multi-page electronic book.

5. An electronic display according to claim 4 further comprising conductive vias extending between adjacent pages and connecting at least one of the first and second sets of addressing means on said adjacent pages.

6. An electronic display according to claim 1 wherein the light valve comprises a polymer-dispersed liquid crystal.

7. An electronic display according to claim 1 wherein the light source comprises an electroluminescent material.

8. An electronic display according to claim 1 wherein the light valves are arranged as series of elongate columns crossing said elongate rows, said light sources and light valves together defining a two-dimensional array of pixels in said photoconductor.

9. An electronic display according to claim 1 wherein the first addressing means comprises a plurality of electrical conductors and means for applying potentials selectively to said conductors, the second addressing means comprises said plurality of light emitting devices and means for generating light selectively from said light emitting devices, and said third addressing means comprises said plurality of light valves and means for selectively setting said light valves to their transmissive or non-transmissive states.

10. An electronic display according to claim 1 having three sets of pixels arranged to display different colors, and wherein the third set of addressing means is arranged to select one of said three sets of pixels to be addressed at any given moment.

11. An electronic display according to claim 1 further comprising a fourth set of addressing means for addressing said pixels, said fourth set being separate from said first, second and third sets of addressing means, each of said pixels of said display being associated with one addressing means in each of said four sets, such that any specific pixel of the display can be addressed by application of signals within predetermined ranges to each of the four addressing means associated with said specific pixel.

12. An electronic display according to claim 1 wherein the electro-optic material comprises an electrophoretic medium.

13. An electronic display according to claim 12 wherein said electrophoretic medium is an encapsulated electrophoretic medium.

14. An electronic display according to claim 1 wherein the electro-optic material comprises a rotating bichromal object material.

15. An electronic display according to claim 1 wherein the electro-optic material operates by principle of one of the following:

rotating bichromal objects, electrochromics, or suspended particles.

16. A method of addressing an electronic display, the method comprising:

providing an electro-optic material having a plurality of pixels;

providing first, second and third sets of addressing means for addressing said pixels, each of said pixels being associated with one addressing means in each of said three sets; and

applying predetermined signals to the three addressing means associated with a specific pixel, thereby addressing said pixel,

wherein at least one of the sets of addressing devices comprises a photoconductor, the display further comprising a plurality of light sources associated with the photoconductor and selectively operable to switch the photoconductor between a conductive and a non-conductive state, the light sources being arranged as a series of elongate rows, each elongate row defining at least one row of pixels of the display; and

(b) light valves disposed between the light sources and the photoconductor and arranged to control transmission of light from the light sources to the photoconductor.

17. An electronic display comprising an electro-optic material having a plurality of pixels, a photoconductor disposed adjacent the electro-optic material and a plurality of light sources associated with the photoconductor and selectively operable to switch the photoconductor between a conductive and a non-conductive state, the light sources being arranged as a series of elongate rows, each elongate row defining at least one row of pixels of the display, the display further comprising light valves disposed between the light sources and the photoconductor and arranged to control transmission of light from the light sources to the photoconductor.

18. An electronic display according to claim 17 wherein the light valves are arranged as a series of elongate columns crossing said elongate rows, said light sources and light valves together defining a two-dimensional array of pixels in said photoconductor.

19. An electronic display according to claim 17 having an electrode on the opposed side of the electro-optic material from the photoconductor.

20. An electronic display according to claim 19 wherein the electrode is patterned into a plurality of elongate elements, the display further comprising means for applying different potentials to differing ones of the elongate elements of the electrode.

21. An electronic display according to claim 17 wherein the light valves are arranged as a series of elongate elements extending parallel to the elongate light sources.

22. An electronic display according to claim 17 wherein the elongate elements of the light valves differ in width from the elongate light sources, such that a plurality of one of the light valves and light sources are contained within the area of one of the other of the light valves and the light sources.