Display unit

• US 20070076431A1
• Filed: 09/25/2006
• Published: 04/05/2007
• Est. Priority Date: 10/03/2005
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Atarashi, Takayuki, Yotsumoto, Naoki, Terakado, Shuichi, Akai, Hiroshi
• Granted Patent: US 7,527,409 B2
• Time in Patent Office: Days
• US Class Current: 362/613
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02B 6/0085 Means for removing heat created by the light source from the package heat extraction or cooling elements for semiconductor light sources in general H01L33/64
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133628 with cooling means

Abstract

In the case that the LED is used as a light source for a backlight such as a display unit or the like, if a lot of current is circulated for securing a brightness, a lot of heat is generated in view of a characteristic of the LED, so that the LED comes to a high temperature, and there is a problem that the characteristic of the LED itself is deteriorated such as a light output is lowered, a long-term service life can not secured, or the like. Further, in the case that a temperature difference exists between a plurality of LEDs, there is a problem that it appears as a brightness irregularity of a screen of the display unit. The display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to an LED mounting surface of a substrate on which the LEDs are mounted, and one or a plurality of fans, a base portion of the heat sink has a substrate mounting surface and a fin constituting surface, the fin constituting surface is approximately perpendicular to the substrate mounting surface, and the fin constituting surface of the base portion and an air supply and exhaust surface of a cooling air are formed in an opposite side to a screen display side of the display.

Claims

1. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and one or a plurality of fans, a base portion of said heat sink has a substrate mounting surface and a fin constituting surface, said fin constituting surface is approximately perpendicular to said substrate mounting surface, and said fin constituting surface of the base portion and an air supply and exhaust surface of a cooling air are formed in an opposite side to a screen display side of the display.

2. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and one or a plurality of fans, a base portion of said heat sink has an approximately L-shaped form, a base surface on which the substrate is mounted, and a base surface in which the fin is constituted are approximately perpendicular to each other, and the base surface in which the fin of the base portion is constituted, and an air supply and exhaust surface of a cooling air are formed in an opposite side to a screen display side of the display.

3. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and two fans attached to both end portions of said heat sink in such a manner that a cooling air circulates in an exhausting direction, and a wind leak preventing cover is provided in an end surface portion of said heat sink in such a manner that an inflow port of the cooling air to said heat sink is formed near a center portion of said heat sink.

4. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and one or a plurality of fans attached to a portion near a center portion of said heat sink in such a manner that a cooling air circulates in a compressing direction, and a wind leak preventing cover is provided in an end surface portion of said heat sink in such a manner that a discharge port of the cooling air from said heat sink is formed near both end portions of said heat sink.

5. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and one or a plurality of fans, a base portion of said heat sink has an approximately L-shaped form, a base surface on which the substrate is mounted, and a base surface in which the fin is constituted are approximately perpendicular to each other, the base surface in which the fin of the base portion is constituted, and an air supply and exhaust surface of a cooling air are formed in an opposite side to a screen display side of the display, and a plurality of fins constituted in the base portion are formed by plate fins arranged approximately in parallel to the base surface on which the substrate is mounted.

6. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and one or a plurality of fans, a base portion of said heat sink has an approximately L-shaped form, a base surface on which the substrate is mounted, and a base surface in which the fin is constituted are approximately perpendicular to each other, the base surface in which the fin of the base portion is constituted, and an air supply and exhaust surface of a cooling air are formed in an opposite side to a screen display side of the display, and a plurality of fins constituted in the base portion are formed by pin-type fins arranged approximately in parallel to the base surface on which the substrate is mounted.

7. An edge light type display unit comprising:

a plurality of light generating sources;

a substrate on which said light generating sources are mounted;

a lens directing light beams from the light generating sources in one direction;

a diffusion plate expanding the light beams input from an incident surface in a side surface and outgoing from said lens to a surface shape so as to irradiate to a front surface; and

a liquid crystal panel attached to a front surface of said diffusion plate,

wherein the display unit is provided with a heat sink attached so as to be thermally contacted with an opposite side to the light generating source mounting surface of said substrate, and two rotating speed variable type fans attached to both end portions of said heat sink in such a manner that a cooling air circulates in an exhausting direction, a wind leak preventing cover is provided in an end surface portion of said heat sink in such a manner that an inflow port of the cooling air to said heat sink is formed near a center portion of said heat sink, a temperature sensor is provided in said light generating source or the substrate on which said light generating source is mounted, so as to be capable of monitoring a temperature thereof, and the rotating speed of the fan is controllable in such a manner that the temperature of said light generating source becomes proper at an abnormal time.