Light unit for display device

• US 20040207995A1
• Filed: 06/16/2003
• Published: 10/21/2004
• Est. Priority Date: 04/18/2003
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Park, Chang Jin, Yun, Dae Young, Park, Jong Hwa, Kim, Chan Soo, Kim, Young Gi
• Application Number:
  US10/461,512
• Publication Number:
  US 20040207995A1
• Time in Patent Office: Days
• US Class Current: 362/31
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0066 characterised by the light source being coupled to the light guide

Abstract

Disclosed is a light unit used for backlighting a display device such as an LCD panel, which emits perpendicularly-directed white surface light by using lateral monochromatic light. The light unit of the invention comprises: a monochromatic light source for emitting monochromatic light; a light guide plate placed at the side of the monochromatic light source, and having a hologram pattern formed on at least one of front and rear faces oriented perpendicular to incident light introduced from the monochromatic light source for emitting light in a direction substantially perpendicular to the incidence direction of light; and a fluorescent layer applied on the front face of the light guide plate for converting perpendicularly-directed emitted light into white light.

Claims

1. A light unit for a display device, comprising:

a monochromatic light source for emitting monochromatic light;

a light guide plate placed at the side of said monochromatic light source, and having a hologram pattern formed on at least one of front and rear faces oriented perpendicular to incident light introduced from said monochromatic light source for emitting light in a direction substantially perpendicular to the incidence direction of light; and

a fluorescent layer applied on said front face of the light guide plate for converting perpendicularly-directed emitted light into white light.

2. The light unit for a display device as set forth in claim 1, wherein said monochromatic light source comprises a blue light source for emitting blue light.

3. The light unit for a display device as set forth in claim 1, wherein said hologram pattern is formed on both of said front and rear faces of the light guide plate.

4. The light unit for a display device as set forth in claim 1, wherein said fluorescent layer contains Yttrium Aluminum Garnet (YAG) powder and binder for enabling application of said fluorescent layer on said light guide plate.

5. The light unit for a display device as set forth in claim 4, wherein said binder comprises transparent resin.

6. The light unit for a display device as set forth in claim 1, wherein said hologram pattern has a diffraction pitch of about 0.1 to 50 μ

m.

7. The light unit for a display device as set forth in claim 6, wherein said hologram pattern has a diffraction pitch of about 0.1 to 5 μ

m.

8. A light unit for a display device, comprising:

a monochromatic light source for emitting monochromatic light;

a light guide plate placed at the side of said monochromatic light source, and having a hologram pattern formed on at least one of front and rear faces oriented perpendicular to incident light introduced from said monochromatic light source for emitting light in a direction substantially perpendicular to the incidence direction of light;

a reflector placed under said rear face of the light guide plate; and

a fluorescent layer applied on said front face of the light guide plate for converting perpendicularly-directed emitted light into white light.

9. The light unit for a display device as set forth in claim 8, wherein said monochromatic light source comprises a blue light source for emitting blue light.

10. The light unit for a display device as set forth in claim 8, wherein said hologram pattern is formed on both of said front and rear faces of the light guide plate.

11. The light unit for a display device as set forth in claim 8, wherein said fluorescent layer contains Yttrium Aluminum Garnet (YAG) powder and binder for enabling application of said fluorescent layer on said light guide plate.

12. The light unit for a display device as set forth in claim 11, wherein said binder comprises transparent resin.

13. The light unit for a display device as set forth in claim 8, wherein said hologram pattern has a diffraction pitch of about 0.1 to 50 μ

m.

14. The light unit for a display device as set forth in claim 13, wherein said hologram pattern has a diffraction pitch of about 0.1 to 5 μ

m.