Electrophoretic display

• US 5,745,094 A
• Filed: 12/28/1994
• Issued: 04/28/1998
• Est. Priority Date: 12/28/1994
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Gordon, Joseph Grover II, Hart, Mark Whitney, McKean, Dennis Richard, Smith, Barton Allen, Swanson, Sally Ann, Homola, Andrew Marian, Schein, Lawrence Brian
• Primary Examiner(s): BRIER, JEFFERY A
• Application Number:
  US08/365,270
• Time in Patent Office: 1,217 Days
• Field of Search: 345/48, 345/107, 359/296
• US Class Current: 345/107
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1677 Structural association of cells with optical devices, e.g. reflectors or illuminating devices

Abstract

The invention relates to an ambient light electrophoretic display comprising a plurality of cells containing a suspension of charged pigment particles in a light-transmissive fluid. Each cell comprises a light-transmissive front window, a nonobstructing collecting electrode and counter electrode disposed in the cell, and a panel having a reflective or absorbing surface.

Claims

1. An ambient light electrophoretic display comprising a plurality of cells containing a suspension of charged pigment particles in a light-transmissive fluid, each cell comprising:

(a) a light-transmissive front window;

(b) a nonobstructing collecting electrode;

(c) a counter electrode; and

(d) a panel having a surface which is light-reflective to reflect incident light back through the cell and the front window.

2. The display of claim 1 wherein the panel is disposed at the rear of the cell.

3. The display of claim 1 wherein the counter electrode is light transmissive.

4. The display of claim 2 wherein the counter electrode is the panel.

5. The display of claim 3 wherein the reflective surface is silvered.

6. The display of claim 5 wherein the pigment particles are opaque.

7. An electrophoretic display comprising a plurality of cells containing a suspension of charged pigment particles in a light-transmissive fluid, each cell comprising:

(a) a light-transmissive front electrode;

(b) a nonobstructing collecting electrode; and

(c) a rear panel having a reflective surface to reflect the incident light back through cell and the front electrode.

8. The display of claim 7 wherein the collecting electrode is disposed on the rear panel.

9. The display of claim 8 wherein the reflective surface is silvered.

10. The display of claim 9 wherein the pigment particles are opaque.

11. An ambient light,reflective, electrophoretic display without backlight comprising a plurality of cells containing a suspension of charged pigment particles in a light-transmissive fluid, each cell comprising:

(a) a light-transmissive front window;

(b) a nonobstructing collecting electrode disposed at the side of the cell;

(c) a counter electrode; and

(d) a panel having a surface which is light-reflective or absorbing.