FLAT PANEL DISPLAY

• US 20080175021A1
• Filed: 03/07/2008
• Published: 07/24/2008
• Est. Priority Date: 06/18/2004
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: CHI MEI Optoelectronics Corporation
• Inventors: Hung, Chen-Pin
• Granted Patent: US 7,732,828 B2
• Time in Patent Office: Days
• US Class Current: 362/606
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 27/0944 Diffractive optical elements, e.g. gratings, holograms gratings per se G02B5/18; holograms used as optical elements per se G02B5/32
• CPC Class Codes: G02B 27/0983 being curved
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H10K 50/85 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 59/879 comprising refractive means, e.g. lenses

Abstract

A flat panel display is provided. The flat panel display includes a display panel. A light guide plate is disposed below the display panel. At least one optical film is disposed between the display panel and the light guide plate. At least one illuminating device package is disposed in proximity to the side of the light guide plate. The illuminating device package includes an illuminating semiconductor device and a lens encapsulating the illuminating semiconductor device. The lens includes two reflective surfaces disposed at either side of a central axis. A plurality of diffractive surfaces are disposed between the reflective surfaces. Each of the diffractive surfaces has a tilt angle respective to the central axis. A first portion of light beams incident to each of the reflective surfaces is reflected to at least one diffractive surface and then diffracted and collected into a first convergent angle.

Claims

1. A flat panel display comprising:

a display panel;

a light guide plate disposed below the display panel;

at least one optical film disposed between the display panel and the light guide plate; and

at least one illuminating device package disposed in proximity to the side of the light guide plate, wherein each illuminating device package includes;

an illuminating semiconductor device, and

a lens encapsulating the illuminating semiconductor device, wherein the lens comprises,

two reflective surfaces disposed at either side of a central axis, and

a plurality of diffractive surfaces disposed between the reflective surfaces, each of the diffractive surfaces having a tilt angle respective to the central axis, wherein a first portion of light beams incident to each of the reflective surfaces is reflected to at least one diffractive surface and then diffracted and collected into a first convergent angle.

2. The flat panel display of claim 1, wherein a second portion of the light beams is projected directly to the at least one diffractive surface, diffracted by the at least one diffractive surface, and collected into a second convergent angle after the light produced by the illuminating semiconductor device enters the lens.

3. The flat panel display of claim 1, wherein the lens comprises a polycarbonate (PC) lens, a polymethylmethacrylate (PMMA) lens, a resin lens, or a glass lens.

4. The flat panel display of claim 1, wherein the at least one optical film is a diffuser plate.

5. The flat panel display of claim 1, wherein the at least one optical film is a prism.

6. The flat panel display of claim 1, wherein the reflective surfaces are disposed symmetrically on both sides of the central axis.

7. The flat panel display of claim 1, wherein the first portion of the light beams incident to each of the reflective surfaces is reflected to the at least one diffractive surface after each reflective surface generates a total internal reflection.

8. The flat panel display of claim 1, wherein at least two diffractive surfaces are disposed symmetrically on both sides of the central axis.

9. The flat panel display of claim 1, wherein two of the diffractive surfaces form an acute angle respective to each reflective surface and the remaining diffractive surfaces form a hemispherical surface.

10. The flat panel display of claim 1, wherein two of the diffractive surfaces form an acute angle respective to each reflective surface and the remaining diffractive surfaces form a triangular surface.

11. The flat panel display of claim 1, wherein the light beams from the illuminating semiconductor device directly projected to the at least one diffractive surface is diffracted by the at least one diffractive surface and collected to the first convergent angle.

12. The flat panel display of claim 1, wherein the at least one diffractive surface is configured to diffract the reflected light beams such that the diffracted light beams are substantially parallel to the central axis.

13. The flat panel display of claim 1, wherein the first convergent angle with respect to the central axis is between about +25 degrees and about −

25 degrees.

14. The flat panel display of claim 1, wherein the reflective surfaces disposed at either side of the central axis are separated.

15. The flat panel display of claim 1, wherein a first diffractive surface contacts a first reflective surface to form a first acute angle, a second diffractive surface contacts a second reflective surface to form a second acute angle, and at least one third diffractive surface extends from the first diffractive surface to the second diffractive surface to form a hemispherical surface.

16. The flat panel display of claim 1, wherein a first diffractive surface contacts a first reflective surface to form a first acute angle, a second diffractive surface contacts a second reflective surface to form a second acute angle, and at least third one diffractive surface extends from the first diffractive surface to the second diffractive surface to form a triangular surface.

17. The flat panel display of claim 1, wherein a first diffractive surface contacts a first reflective surface to form a first acute angle, a second diffractive surface contacts a second reflective surface to form a second acute angle, and at least one third diffractive surface extends from the first diffractive surface to the second diffractive surface to form a semi-vase-shaped surface.

18. The flat panel display of claim 1, wherein a first diffractive surface contacts a first reflective surface to form a first acute angle, a second diffractive surface contacts a second reflective surface to form a second acute angle, a third diffractive surface contacts the first diffractive surface to form a third acute angle, and a fourth diffractive surface contacts the second diffractive surface to form a fourth acute angle.

19. A method for forming a flat panel display, comprising:

disposing a light guide plate below a display panel;

disposing at least one optical film between the display panel and the light guide plate; and

disposing at least one illuminating device package in proximity to the side of the light guide plate,

wherein a method for forming the illuminating device package includes;

forming a light emitting diode device over a substrate; and

forming a lens encapsulating the light emitting diode device, the lens comprising;

two reflective surfaces disposed substantially symmetrically at either side of a central axis, the reflective surfaces being configured to reflect portions of light beams to at least one of the diffractive surfaces; and

a plurality of diffractive surfaces separating the reflective surfaces, the diffractive surfaces being configured to diffract the reflected light beams into a convergent angle, each of the diffractive surfaces having a tilt angle respective to the central axis.

20. The method of claim 19, wherein forming the lens comprises:

forming a first diffractive surface contacting a first reflective surface to form a first acute angle,

forming a second diffractive surface contacting a second reflective surface to form a second acute angle; and

forming at least third diffractive surface extends from the first diffractive surface to the second diffractive surface to form a hemispherical surface, a triangular surface or a semi-vase-shaped surface.