LED Staggered back lighting panel for LCD module

• US 4,573,766 A
• Filed: 12/19/1983
• Issued: 03/04/1986
• Est. Priority Date: 12/19/1983
• Status: Expired due to Fees

• Current Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Original Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Inventors: Giurtino, Joel F., Bournay, Frederick M. Jr.
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Lewis, David
• Application Number:
  US06/562,855
• Time in Patent Office: 806 Days
• Field of Search: 350/345, 350/331 R, 362/19, 362/23, 362/26-31, 362/800, 340/716, 40/442, 40/448, 40/546, 40/452, 40/451
• US Class Current: 349/65
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

The LED backlighting panel includes a roughened flat surface area and side edges with holes therein for receiving light emitting diodes that are supplied from a direct current power source which can have an adjustable duty cycle to provide a backlighting panel that has a minimal power consumption in a liquid crystal display (LCD) module.

Claims

1. A thin, single layer backlighting panel for use in a visual display device, comprising a liquid crystal display unit, said back lighting panel comnprising a thin, rectangular piece of light transmitting plastic material having a front surface and a back surface and two opposite elongated edges, said two opposite elongated edges having holes therein, light emitting means being positioned along and extending into said holes of said two opposite elongate edges of said rectangular piece of material for emitting light into said piece of material and comprising a plurality of light emitting diodes, a plurality of said light emitting diodes along and within one edge being staggered or offset from a plurality of the light emitting diodes along and within the opposite edge, and means on at least the front flat surface of said piece of material for diffusing light at said front flat surface to provide diffused backlight for said visual display device.

2. The panel of claim 1 wherein said flat rectangular piece of light transmitting material is a thin transparent piece of plastic material and said opposite elongate edges have holes therein for mounting said light emitting diodes.

3. The panel of claim 1 where said diffusing means are defined by a roughened surface area on said front flat surface.

4. The panel of claim 3 wherein said roughened light diffusing surface area is sanded.

5. The panel according to claim 1 wherein the lontitudinal margins adjacent to said opposite side edges are covered with an opaque covering.

6. The panel of claim 5 wherein said opaque covering is white paint.

7. The panel of claim 1 wherein said light emitting diodes are capable of being powered from an adjustable duty cycle source.

8. The panel of claim 1 having a thickness slightly greater than the diameter of each of the light emitting means diodes.

10. The method of claim 1 wherein an adjustable duty cycle direct current is supplied to said light emitting diodes.

9. A method for providing backlighting in a visual display device including:

providing a liquid crystal display unit, providing a flat rectangular panel of light transmitting material having a flat front surface, a flat back surface, and opposite elongate edges;

providing a light diffusing surface area on said front surface of said panel;

directing light into said elongate edges of said panel of light transmitting material to cause said light transmitting material to transmit diffused light therefrom through said front flat surface thereby backlighting said liquid crystal unit;

forming said light emitting means from a plurality of light emitting diodes; and

positioning a plurality of the light emitting diodes on one edge to be staggered or offset from a plurality of the light emitting diodes along the opposite edge.

11. The method of claim 9 including the step of sanding said surface to provide said light diffusion surface area.

12. The method of claim 9 including covering the elongate margin of said one surface adjacent said opposite side edges with an opaque covering.