Light emitting diode array module for providing backlight and backlight unit having the same

• US 7,217,004 B2
• Filed: 07/14/2004
• Issued: 05/15/2007
• Est. Priority Date: 05/03/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Park, Young Sam, Park, Jung Kyu, Kim, Chang Wook
• Primary Examiner(s): Luebke; Renee
• Assistant Examiner(s): Bennett; Zahra I.
• Application Number:
  US10/890,201
• Publication Number:
  US 20050243576A1
• Time in Patent Office: 1,035 Days
• Field of Search: 362/800, 362/30, 362/294, 362/240, 362/244, 362/245, 362/231
• US Class Current: 362/240
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A Light Emitting Diode (LED) array module, which can be used as backlight, includes a bar-shaped Printed Circuit Board (PCB) on which conductive patterns for transmitting power are formed, a base formed on the PCB and made of a heat conductive material, a plurality of LED chips mounted on the base in a line and electrically connected to the conductive patterns of the PCB, a reflector formed to surround the plurality of the LED chips and adapted to reflect light radiated from the plurality of LED chips upward, and a lens formed above the plurality of LED chips and reflector to have a bar shape and adapted to diffuse the light radiated from the plurality of LED chips and reflector in a horizontal direction.

Claims

1. A backlight unit for a display device, said backlight unit comprising a plurality of Light Emitting Diode (LED) array modules arranged in a plurality of rows and columns, the LED array modules being arranged at regular intervals in each of the rows, each of LED array modules in a first row being located to face a space between two adjacent LED array modules in a second row in a relationship of two adjacent rows;

each of said LED array modules comprising;

a bar-shaped Printed Circuit Board (PCB) on which conductive patterns for transmitting power are formed;

a base formed on the PCB and made of a heat conductive material;

a plurality of LED chips mounted on the base in a line and electrically connected to the conductive patterns of the PCB;

a reflector formed to surround the plurality of the LED chips and adapted to reflect light radiated from the plurality of LED chips upward; and

a lens which is formed above the plurality of LED chips and the reflector, and has a bar shape;

wherein said lens diffuses, in a horizontal direction, the light radiated from the plurality of LED chips and reflected by the reflector.

2. A Light Emitting Diode (LED) array module for use as a light source of a backlight unit, said LED module comprising:

a bar-shaped Printed Circuit Board (PCB) on which conductive patterns for transmitting power are formed;

a base formed on the PCB and made of a heat conductive material;

a plurality of LED chips mounted on the base in a line and electrically connected to the conductive patterns of the PCB;

a reflector formed to surround the plurality of the LED chips and adapted to reflect light radiated from the plurality of LED chips upward; and

a lens which is formed above the plurality of LED chips and the reflector, and has a bar shape;

wherein

said lens diffuses, in a horizontal direction, the light radiated from the plurality of LED chips and reflected by the reflector; and

the lens has a cross section taken perpendicular to a longitudinal direction of said bar shape, said cross section having a star shape comprising multiple triangular points radiating from a center.

3. A Light Emitting Diode (LED) array module, comprising:

a Printed Circuit Board (PCB) which is elongated in a longitudinal direction of said module and on which conductive patterns for transmitting power are formed;

a base which is elongated in the longitudinal direction of said module, placed above the PCB, and made of a heat conductive material;

a plurality of LED chips which are mounted on an upper surface of the base in a line extending along the longitudinal direction of said module, said LED chips being electrically connected to the conductive patterns of the PCB;

a reflector which is elongated in the longitudinal direction of said module, surrounds said LED chips, and is adapted to upwardly reflect light radiated from the LED chips;

a lens which is elongated in the longitudinal direction of said module, placed above said LED chips and said reflector, and adapted to diffuse, in a horizontal direction, light coming from said LED chips and said reflector; and

an encapsulant made of a transparent material covering and protecting said LED chips;

said encapsulant being elongated in the longitudinal direction of said module and confined within a space defined by inner walls of said reflector.

4. The LED module as set forth in claim 3, wherein the lens is upwardly spaced from said encapsulant.

5. A Light Emitting Diode (LED) array module, comprising:

a Printed Circuit Board (PCB) which is elongated in a longitudinal direction of said module and on which conductive patterns for transmitting power are formed;

a base which is elongated in the longitudinal direction of said module, placed above the PCB, and made of a heat conductive material;

a plurality of LED chips which are mounted on an upper surface of the base in a line extending alone the longitudinal direction of said module, said LED chips being electrically connected to the conductive patterns of the PCB;

a reflector which is elongated in the longitudinal direction of said module, surrounds said LED chips, and is adapted to upwardly reflect light radiated from the LED chips; and

a lens which is elongated in the longitudinal direction of said module, placed above said LED chips and said reflector, and adapted to diffuse, in a horizontal direction, light coming from said LED chips and said reflector;

wherein said reflector is positioned on said PCB and surrounds not only said led chips but also said base.

6. A backlight unit for a display device, said backlight unit comprising a plurality of Light Emitting Diode (LED) array modules, wherein

said LED array modules are arranged in a plurality of rows;

the longitudinal directions of the LED array modules in each of said rows are aligned; and

the LED array modules in two adjacent of said rows are staggered, in a direction perpendicular to said rows, with respect to each other;

each of said LED array modules comprising;

a Printed Circuit Board (PCB) which is elongated in a longitudinal direction of said module and on which conductive patterns for transmitting power are formed;

a base which is elongated in the longitudinal direction of said module, placed above the PCB, and made of a heat conductive material;

a plurality of LED chips which are mounted on an upper surface of the base in a line extending along the longitudinal direction of said module, said LED chips being electrically connected to the conductive patterns of the PCB;

a reflector which is elongated in the longitudinal direction of said module, surrounds said LED chips, and is adapted to upwardly reflect light radiated from the LED chips; and

a lens which is elongated in the longitudinal direction of said module, placed above said LED chips and said reflector, and adapted to diffuse, in a horizontal direction, light coming from said LED chips and said reflector.

7. The backlight unit as set forth in claim 6, wherein the numbers of the LED array modules in two adjacent of said rows are different.

8. A Light Emitting Diode (LED) array module, comprising:

a Printed Circuit Board (PCB) which is elongated in a longitudinal direction of said module and on which conductive patterns for transmitting power are formed;

a base which is elongated in the longitudinal direction of said module, placed above the PCB, and made of a heat conductive material;

a plurality of LED chips which are mounted on an upper surface of the base in a line extending along the longitudinal direction of said module, said LED chips being electrically connected to the conductive patterns of the PCB;

a reflector which is elongated in the longitudinal direction of said module, surrounds said LED chips, and is adapted to upwardly reflect light radiated from the LED chips; and

a lens which is elongated in the longitudinal direction of said module, placed above said LED chips and said reflector, and adapted to diffuse, in a horizontal direction, light coming from said LED chips and said reflector;

wherein

the lens comprises a plurality of projections elongated in said longitudinal direction; and

lens has a cross section taken perpendicular to said longitudinal direction, said cross section comprising multiple triangular points radiating from a center, each of said triangular points corresponding to one of said projections.