Light-modulating, electrically responsive privacy screen

• US 6,552,762 B1
• Filed: 01/06/2000
• Issued: 04/22/2003
• Est. Priority Date: 01/06/2000
• Status: Active Grant

• Current Assignee: Iris Optronics Co., Ltd.
• Original Assignee: Eastman Kodak Company
• Inventors: Stephenson, Stanley W., Boettcher, John W., Giacherio, David J.
• Primary Examiner(s): Kim, Robert H.
• Assistant Examiner(s): CHUNG, DAVID Y
• Application Number:
  US09/478,487
• Time in Patent Office: 1,202 Days
• Field of Search: 349/86, 349/92, 349/89, 349/93, 349/80, 349/183, 349/184
• US Class Current: 349/86
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals

Abstract

A light-modulating, electrically responsive privacy screen includes a transparent substrate and an electrically conductive layer formed over the substrate. The privacy screen further includes a light-modulating layer disposed over the electrically conductive layer and including at least one dispersible light-modulating material and coalescence limiting material into which the dispersible light-modulating material(s) is provided so that such dispersible light-modulating material coalesces to form a set domains having at least two optical states, the first optical state being present in the absence of an electrical field and the second being caused by the application of an electrical field and wherein one of the optical states cause the light-modulating layer to be transparent and the other optical state causes the light-modulating layer to restrict a user viewing through the privacy screen and thereby provide an appropriate level of privacy.

Claims

1. A light-modulating, electrically responsive privacy screen comprising:

(a) a transparent substrate;

(b) an electrically conductive layer formed over the substrate;

(c) a light-modulating layer disposed over the electrically conductive layer and including at least one dispersible light-modulating material and coalescence limiting colloidal material into which the dispersible light-modulating material(s) is provided so that such dispersible light-modulating material coalesces to form a set of domains of uniform size having at least two optical states, the first optical state being present in the absence of an electrical field and the second being caused by the application of an electrical field and wherein one of the optical states cause the light-modulating layer to be transparent and the other optical state causes the light-modulating layer to restrict a user viewing through the privacy screen and thereby provide an appropriate level of privacy.

2. The light-modulating, electrically responsive privacy screen of claim 1, further comprising:

(d) uniform set of domains being responsive to an applied electric field to change optical states;

(e) a second transparent conductor layer disposed over the light-modulating layer and adapted to provide a field when an electrical potential is applied the conductive layer and the second conductive layer so that the uniform domains change optical state.

3. The light-modulating, electrically responsive privacy screen of claim 2, wherein the dispersible light-modulating material is a liquid crystal material.

4. The light-modulating, electrically responsive privacy screen of claim 3, wherein the dispersible light-modulating material is a nematic liquid crystal material.

5. The light-modulating, electrically responsive privacy screen of claim 3 further including a dichroic dye.