Methods and apparatus for providing a luminous writing surface

• US 7,543,951 B2
• Filed: 04/30/2007
• Issued: 06/09/2009
• Est. Priority Date: 05/03/2006
• Status: Active Grant

• Current Assignee: Signify North America Corporation (Signify N.V.)
• Original Assignee: Philips Solid-State Lighting Solutions (Koninklijke Philips N.V.)
• Inventors: Koerner, Brad E., Dowling, Kevin J.
• Primary Examiner(s): Choi; Jacob Y
• Application Number:
  US11/741,986
• Publication Number:
  US 20070258231A1
• Time in Patent Office: 771 Days
• Field of Search: 362/99, 362/600, 362/601, 362/612, 362/27, 362/98, 362/253, 362/800, 362/276, 362/394, 362/802, 281/39, 281/51, 206/472, 206/232, 345/179, 345/82, 345/84, 404/52
• US Class Current: 362/99
• CPC Class Codes: B43L 1/004 with illuminating devices
• CPC Class Codes: H04M 1/0283 for providing a decorative aspect, e.g. customization of casings, exchangeable faceplate

Abstract

Disclosed herein are methods and apparatus for providing a luminous writing surface, whose color, color temperature, and/or brightness are controlled to achieve a desired contrast between the writing surface and markings removably made thereon. For example, LED-based light sources and/or LED-based controllable lighting units can be employed to back-light or edge-light a transparent or translucent material thereby providing the luminous writing surface.

Claims

1. An apparatus having a luminous writing surface configured to receive a removable marking thereon, the apparatus comprising:

an essentially planar member having a front surface, at least one side surface, and a back surface, the front surface comprising the writing surface;

at least one light source associated with the essentially planar member for irradiating at least one of the side surface and the back surface thereof with visible light perceivable by an observer from the front surface, the visible light providing at least one background color for the removable marking when received on the writing surface; and

at least one controller coupled to the at least one light source and configured to control at least one of a color, a color temperature and an intensity of the visible light so as to provide the at least one background color, wherein the at least one controller is configured to control the at least one background color based at least in part on (i) ambient light in an environment around the apparatus and/or (ii) a color of the removable marking.

2. The apparatus of claim 1, wherein the essentially planar member is configured to both facilitate diffusion of the visible light over a substantial portion of the writing surface and receive the removable marking over the substantial portion of the writing surface.

3. The apparatus of claim 1, wherein the essentially planar member comprises essentially rigid material.

4. The apparatus of claim 1, wherein the essentially planar member comprises flexible material.

5. The apparatus of claim 1, wherein at least one of the front surface, side surface, and the back surface of the essentially planar member comprises a pattern formed thereon.

6. The apparatus of claim 1, wherein at least one of the front surface, side surface, and the back surface of the essentially planar member is mechanically altered for interacting with the visible light.

7. The apparatus of claim 1, wherein the essentially planar member comprises glass-based, polycarbonate, or acrylic material.

8. The apparatus of claim 1, wherein the essentially planar member comprises a translucent or transparent material and wherein the at least one light source is disposed in a plane substantially parallel to the back surface thereof so as to irradiate the back surface with the visible light and provide substantially homogeneous illumination of the front surface.

9. The apparatus of claim 1, wherein the essentially planar member comprises a coating disposed over the back surface for facilitating diffusion of the visible light.

10. The apparatus of claim 1, wherein the at least one light source includes at least one LED-based light source.

11. The apparatus of claim 1, wherein the color of the visible light includes at least one non-white color.

12. The apparatus of claim 1, wherein the visible light includes essentially white light.

13. The apparatus of claim 1, where the at least one controller is configured to control the at least one background color so as to alter a contrast between the removable marking and the writing surface.

14. The apparatus of claim 1, wherein the removable marking includes at least two markings having different colors, and wherein the at least one controller is configured to control the at least one background color so as to increase a contrast between the at least two markings.