Electrofluidic chromatophore (EFC) display apparatus

• US 9,070,322 B2
• Filed: 08/03/2012
• Issued: 06/30/2015
• Est. Priority Date: 08/05/2011
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Creator Technology BV
• Inventors: Huitema, Hjalmar Edzer Ayco, Touwslager, Fredericus Johannes, van Lieshout, Petrus
• Primary Examiner(s): Mengistu, Amare
• Assistant Examiner(s): XAVIER, ANTONIO J
• Application Number:
  US13/566,971
• Publication Number:
  US 20130141405A1
• Time in Patent Office: 1,061 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G02B 26/005 based on electrowetting
• CPC Class Codes: G09G 3/28 using luminous gas-discharge panels, e.g. plasma panels
• CPC Class Codes: G09G 3/348 based on the deformation of a fluid drop, e.g. electrowetting
• CPC Class Codes: Y10T 29/49124 On flat or curved insulated base, e.g., printed circuit, etc.

Abstract

A display apparatus includes a plurality of electrofluidic chromatophore (EFC) pixel cells. Each pixel cell includes a fluid holder for holding a polar fluid and a non-polar fluid having differing display properties, the fluid holder including a reservoir having an orifice with a small visible area projected in the direction of a viewer onto the polar fluid, and a channel with a geometry having a large visible area projected in the direction of a viewer onto the polar fluid. The channel is connected to the reservoir via said orifice so as to enable free movement of the polar fluid and non-polar fluid between the channel and the reservoir. The reservoir is formed in a laminated resin structure of homogenous resin film layers, including an orifice film layer and a reservoir film layer.

Claims

1. A display apparatus comprising a circuit board having row and column electrodes arranged thereon to connect a driver to a plurality of electrofluidic chromatophore (EFC) pixel cells provided on the circuit board, wherein each pixel cell comprises:

a fluid holder for holding a polar fluid and a non-polar fluid having differing display properties;

wherein the fluid holder comprises a reservoir having an orifice with a small visible area projected in the direction of a viewer, and wherein the fluid holder further comprises a channel with a geometry having a large visible area projected in the direction of a viewer, the channel being connected to the reservoir via said orifice so as to enable free movement of the polar fluid and non-polar fluid between the channel and the reservoir, at least part of a surface of the channel comprising a wetting property and at least two pixel cell terminals connectable to the row and column electrodes on the circuit board and being configured to supply a supply voltage to at least part of the surface of the channel comprising the wetting property for supply voltage controlled movement of polar fluid;

the at least two pixel cell terminals dielectrically separated from the polar fluid;

wherein the reservoir is formed in a stacked structure of homogenous film layers arranged on the circuit board, the structure at least comprising an orifice film layer and a reservoir film layer, wherein the reservoir arranged in the reservoir layer is obscured in the direction of a viewer by the orifice film layer, said orifice film layer defining a smallest orifice area that is smaller than a cross sectional area formed in the reservoir film layer; and

wherein the reservoir stack structure includes a reservoir layer forming a reservoir with a reservoir height ranging between 15-50 micrometer, and an orifice layer with a thickness ranging between 1 and 15 micrometer.

2. The display apparatus according to claim 1, wherein the orifice film layer is formed by a laminate resin layer of a homogenous thickness that is laminated in the stacked structure.

3. The display apparatus according to claim 1, wherein the reservoir film layer is formed by a laminate resin layer of a homogenous thickness that is laminated in the stacked structure.

4. The display apparatus according to claim 1, wherein any of the film layers in the stack structure is formed by laminate resin film layers of a homogenous thickness.

5. The display apparatus according to claim 1, wherein the film layers have mutually differing thicknesses, with the orifice film layer having a thickness smaller than the reservoir layer.

6. The display apparatus according to claim 1, wherein the film layers are formed by a dry film curable resist layer forming the orifice and/or reservoir walls with zero inclination.

7. The display apparatus according to claim 1, wherein the orifice and/or reservoir layer have a coinciding wall to form the orifice.

8. The display apparatus according to claim 1, wherein the reservoir film layer comprises a reservoir structure with support spacers supporting the orifice layer.

9. A method of manufacturing a display apparatus comprising a circuit board having row and column electrodes arranged thereon to connect a driver to a plurality of electrofluidic chromatophore (EFC) pixel cells provided on the circuit board, the method comprises:

providing a fluid holder for holding a polar fluid and a non-polar fluid having differing display properties and at least two pixel cell terminals connectable to the row and column electrodes on the circuit board;

wherein the fluid holder is with a reservoir having an orifice with a small visible area projected in the direction of a viewer, and wherein the fluid holder is provided a channel with a geometry having a large visible area projected in the direction of a viewer, the channel being connected to the reservoir via said orifice so as to enable free movement of the polar fluid and non-polar fluid between the channel and the reservoir, at least part of a surface of the channel comprising a wetting property and at least two pixel cell terminals connectable to the row and column electrodes on the circuit board and being configured to supply a supply voltage to at least part of the surface of the channel comprising the wetting property for supply voltage controlled movement of polar fluid;

the at least two pixel cell terminals dielectrically separated from the polar fluid;

wherein the reservoir is formed in a stacked structure of homogenous film layers arranged on the circuit board, the structure at least comprising an orifice film layer and a reservoir film layer, wherein the reservoir arranged in the reservoir layer is obscured in the direction of a viewer by the orifice film layer, said orifice film layer defining a smallest orifice area that is smaller than a cross sectional area formed in the reservoir film layer; and

wherein the reservoir stack structure includes a reservoir layer forming a reservoir with a reservoir height ranging between 15-50 micrometer, and an orifice layer with a thickness ranging between 1 and 15 micrometer.

10. A method according to claim 9, wherein the orifice film layer is formed by laminating the orifice layer as a dry film resin layer of homogenous thickness on a reservoir layer in the stacked structure.