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

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.