CN101220915A - Light source module and backlight unit - Google Patents

Abstract

A light source module includes a circuit board, a plurality of light-emitting elements and at least one heat-dissipating element. The circuit board has a patterned metal layer, the patterned metal layer includes a plurality of connecting parts and a patterned circuit, and the patterned circuit connects the connecting parts. The light-emitting elements are respectively arranged on one of the connecting parts. The heat-dissipating element is arranged on the circuit board and contacts the patterned metal layer. The heat-dissipating element and the light-emitting element are located on the same side of the circuit board. The light source module has good heat-dissipating efficiency. In addition, the present invention also provides a backlight unit using the light source module.

Description

Light source module and backlight unit

technical field

The present invention relates to a light source module, and in particular to a light source module applicable to a backlight unit (BLU) and a backlight unit using the light source module.

Background technique

In recent years, the flat panel display (flat panel display), developed in conjunction with optoelectronic and semiconductor manufacturing technologies, has gradually become the mainstream of display products due to its advantages of thin thickness and light weight. Common flat panel displays include liquid crystal display (liquid crystal display, LCD), organic electro-luminescence display (organic electro-luminescence display, OLED) and plasma display panel (PDP), among which the market penetration rate of liquid crystal display is relatively high. .

A liquid crystal display is mainly composed of a liquid crystal display panel (LCD panel) and a backlight unit, wherein the backlight unit is used to provide the surface light source required by the liquid crystal display panel. A conventional backlight unit uses a cold cathode fluorescent lamp (CCFL) as a light source. Recently, a light emitting diode (LED) is also used as a light emitting source of a backlight unit.

Since the LEDs generate heat when they emit light, if the heat dissipation of the backlight unit is not good, the temperature of the LEDs will be too high, which will reduce the luminous efficiency of the LEDs and shift the emission wavelength, thereby affecting the display quality of the LCD.

Contents of the invention

The invention provides a light source module, which has better heat dissipation efficiency.

The invention also provides a backlight unit for providing a surface light source with relatively stable quality.

In order to achieve the above advantages, the present invention provides a light source module, which includes a circuit board, a light emitting element and a heat dissipation element. The circuit board has a patterned metal layer, and the patterned metal layer includes connection parts and pattern lines, and the pattern lines connect the connection parts. The light emitting element is arranged on the connection part. The heat dissipation element is arranged on the circuit board and contacts the patterned metal layer. In addition, the heat dissipation element and the light emitting element are located on the same side of the circuit board.

In an embodiment of the present invention, the above-mentioned patterned metal layer further includes at least one heat dissipation pad, and the heat dissipation pad is connected to the connecting portion. The heat dissipation element is arranged on the heat dissipation pad.

In an embodiment of the present invention, the above-mentioned patterned metal layer includes a plurality of heat dissipation pads, and the heat dissipation pads are respectively connected to one of the connection parts.

In an embodiment of the present invention, the above-mentioned light source module includes a plurality of heat dissipation elements, and the heat dissipation elements are respectively arranged on one of the heat dissipation pads.

In an embodiment of the present invention, the above-mentioned light source module includes a plurality of heat dissipation elements, and the heat dissipation elements are respectively arranged between two adjacent light emitting elements.

In an embodiment of the present invention, the above-mentioned light source module further includes at least one heat conduction medium, and the heat conduction medium is disposed between the heat dissipation element and the heat dissipation pad.

In an embodiment of the present invention, the above-mentioned heat dissipation element is a passive heat dissipation element.

In an embodiment of the present invention, the above-mentioned heat dissipation element is a metal block.

In an embodiment of the present invention, the above-mentioned light-emitting element is a light-emitting diode.

In an embodiment of the present invention, the above-mentioned circuit board is a flexible printed circuit board (FPCB).

In an embodiment of the present invention, the above-mentioned circuit board is a printed circuit board (PCB).

The present invention also provides a backlight unit, which includes a light source module and a light guide plate (LGP) disposed beside the light source module. The light source module includes a circuit board, a light emitting element and a heat dissipation element. The circuit board has a patterned metal layer, and the patterned metal layer includes connection parts and pattern lines, wherein the pattern lines connect the connection parts. The light emitting element is arranged on the connection part. The heat dissipation element is arranged on the circuit board and contacts the patterned metal layer. The heat dissipation element and the light emitting element are located on the same side of the circuit board, and the heat dissipation element is respectively arranged between two adjacent light emitting elements. In addition, the side of the light guide plate has grooves and a light incident surface connected between the grooves. The light incident surface is opposite to the light emitting element, and the heat dissipation element is against the groove.

In an embodiment of the present invention, the above-mentioned patterned metal layer further includes a plurality of heat dissipation pads, and the heat dissipation pads are respectively connected to one of the connection parts. The heat dissipation element is arranged on the heat dissipation pad.

In an embodiment of the present invention, the above-mentioned light source module further includes a plurality of heat-conducting media, and the heat-conducting media are arranged between the heat dissipation element and the heat dissipation pad.

In an embodiment of the present invention, the above-mentioned heat dissipation element is a passive heat dissipation element.

In an embodiment of the present invention, the above-mentioned heat dissipation element is a metal block.

In an embodiment of the present invention, the above-mentioned light-emitting element is a light-emitting diode.

In an embodiment of the present invention, the above-mentioned circuit board is a printed circuit board.

In an embodiment of the present invention, the above-mentioned circuit board is a flexible circuit board.

In the light source module of the present invention, since the heat dissipation element and the light emitting element are located on the same side of the circuit board, the heat energy generated by the light emitting element can be directly conducted to the heat dissipation element through the patterned metal layer, which can effectively dissipate the heat generated by the light emitting element. thermal energy. Since the light source module of the present invention has better heat dissipation efficiency, the backlight unit using the light source module can provide a surface light source with relatively stable quality.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, the preferred embodiments are exemplified below and described in detail in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a top view of a light source module according to an embodiment of the present invention;

Fig. 2 is a schematic sectional view along the I-I' line of Fig. 1;

3 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention;

FIG. 4 is a schematic diagram of a backlight unit according to an embodiment of the invention.

Wherein, the reference signs are explained as follows:

100, 100': light source module 110: circuit board

112: Substrate 112a: Bearing surface

114, 114': patterned metal layer 114a: connecting part

114b: pattern circuit 114c: cooling pad

120: Light emitting element 122: Pin

130: heat dissipation element 140: heat conduction medium

200: Backlight unit 210: Light guide plate

212: Side of the light guide plate 212a: Groove

212b: light incident surface

Detailed ways

Fig. 1 is a top view of a light source module according to an embodiment of the present invention, and Fig. 2 is a schematic cross-sectional view along line I-I' of Fig. 1 . Referring to FIG. 1 and FIG. 2 , the light source module 100 of this embodiment includes a circuit board 110 , a plurality of light emitting elements 120 and a heat dissipation element 130 . The circuit board 110 has a patterned metal layer 114. Furthermore, in this embodiment, the circuit board 110 includes a substrate 112, and the substrate 112 has a bearing surface 112a, and the patterned metal layer 114 is disposed on the bearing surface 112a. The patterned metal layer 114 includes a plurality of connection portions 114a and pattern lines 114b, and the pattern lines 114b are connected to the connection portions 114a. The light emitting elements 120 are respectively disposed on one of the connecting portions 114a. The heat dissipation element 130 is disposed on the circuit board 110 and contacts the patterned metal layer 114 . The heat dissipation element 130 and the light emitting element 120 are located on the same side of the circuit board 110 .

In the above-mentioned light source module 100 , the connecting portion 114 a includes, for example, a first portion located below the light emitting element 120 and a second portion located beside the first portion, wherein the pattern line 114 b is connected to the second portion. In addition, the patterned metal layer 114 may further include a heat dissipation pad 114c connecting the plurality of connecting portions 114a. In detail, the heat dissipation pad 114c is connected to the first portion of the connecting portion 114a, and the heat dissipation element 130 is disposed on the heat dissipation pad 114c. In this embodiment, the heat dissipation element 130 can be fixed on the heat dissipation pad 114c by welding, for example, through a heat conduction medium (not shown in the figure) between the heat dissipation element 130 and the heat dissipation pad 114c, wherein the heat conduction medium can be It is solder, heat dissipation silicone sheet or heat dissipation glue, but it is not limited to this.

Based on the above, the heat dissipation element 130 may be a passive heat dissipation element, such as a heat sink or a metal block, which can provide heat dissipation effect without activation. The material of the heat dissipation element 130 can be selected from materials with high thermal conductivity, such as copper, aluminum and the like. In addition, the light emitting element 120 is, for example, a light emitting diode, but not limited thereto. Two leads 122 of the light-emitting element 120 are electrically connected to the second portion of the connecting portion 114a, and the light-emitting area (ie, the heating area) of the light-emitting element 120 is located above the first portion of the connecting portion 114a. In addition, the circuit board 110 may be a flexible circuit board or a printed circuit board.

In this embodiment, since the heat dissipation element 130 and the light emitting element 120 are located on the same side of the circuit board 110, and the heat dissipation pad 114c and the connecting portion 114a belong to the same layer (that is, the patterned metal layer 114), the heat generated by the light emitting element 120 It can be quickly transmitted to the heat dissipation pad 114c through the connection portion 114a, and then to the heat dissipation element 130 on the heat dissipation pad 114c. In this way, the heat energy generated by the light emitting element 120 can be effectively dissipated, so as to avoid the phenomenon that the luminous efficiency of the light emitting element 120 is reduced and the light emitting wavelength shifts due to the overheating of the light emitting element 120 .

It should be noted that, in the above-mentioned light source module 100, the number of heat dissipation pads 114c may be multiple, and the number of heat dissipation elements 130 may also be multiple. In this case, each heat dissipation pad 114c is respectively connected to one of the connecting portions 114a, and each heat dissipation element 130 is disposed on one of the heat dissipation pads 114c.

Fig. 3 is a schematic diagram of a light source module according to another embodiment of the present invention. Referring to FIG. 3 , the structure of the light source module 100' of this embodiment is similar to that of the light source module 100 of FIG. 2 , and only the differences will be described below. The light source module 100' has multiple heat dissipation elements 130, and the number of heat dissipation pads 114c of the patterned metal layer 114' of the circuit board 110 of the light source module 100' is multiple. The heat dissipation elements 130 are respectively arranged between two adjacent light emitting elements 120 . In other words, the heat dissipation pads 114c of the patterned metal layer 114' are respectively located between two adjacent connecting portions 114a. In addition, the light source module 100' further includes a plurality of heat conduction media 140, and the heat conduction media 140 are arranged between the heat dissipation element 130 and the heat dissipation pad 114c. In other words, the heat dissipation element 130 is fixed on the heat dissipation pad 114c through the heat conduction medium 140 . The heat conduction medium may be solder, heat dissipation silica gel or heat dissipation glue, but is not limited thereto.

Since the advantages of the light source module 100' of this embodiment are similar to those of the above-mentioned light source module 100, they will not be repeated here. In addition, the above-mentioned light source modules 100, 100' can be applied in a backlight unit, and the light source module 100' will be taken as an example below to illustrate the backlight unit of the present invention with reference to the accompanying drawings.

FIG. 4 is a schematic diagram of a backlight unit according to an embodiment of the invention. Referring to FIG. 4 , the backlight unit 200 of this embodiment includes a light guide plate 210 and the aforementioned light source module 100 ′, wherein the light source module 100 ′ is disposed beside the light guide plate 210 . One side 212 of the light guide plate 210 has a plurality of grooves 212a and a plurality of light incident surfaces 212b connected between the grooves 212a. These light incident surfaces 212b are respectively opposite to one of the light emitting elements 120 of the light source module 100', and the heat dissipation elements 130 of the light source module 100' are respectively abutted against one of the grooves 212a.

Since the light guide plate 210 of this embodiment has a plurality of grooves 212a, the grooves 212a are used to accommodate the heat dissipation elements 130, so larger heat dissipation elements 130 can be used, which can further improve the heat dissipation efficiency of the light source module 100' In order to avoid the phenomenon that the luminous efficiency of the light-emitting element 120 is too high and the luminous efficiency is reduced and the luminous wavelength is shifted. In addition, since the groove 212 a of the light guide plate 210 is formed beside the light incident surface 212 b, it will not affect the light provided by the light emitting element 120 from entering the light guide plate 210 . Therefore, the backlight unit 200 of this embodiment can provide a surface light source with relatively stable quality. Therefore, applying the backlight unit 200 to a liquid crystal display can improve the display quality of the liquid crystal display.

In summary, the present invention has at least the following advantages:

1. In the present invention, since the light-emitting element and the heat dissipation element are located on the same side of the circuit board, and the heat dissipation pad and the connection part belong to the same patterned metal layer, the heat generated by the light-emitting element can be quickly transmitted through the connection part and the heat dissipation pad. to the cooling element. Therefore, the light source module of the present invention can effectively dissipate the heat energy generated by the light-emitting element, thereby avoiding the reduction of light-emitting efficiency and the shift of light-emitting wavelength caused by the high temperature of the light-emitting element.

2. The light source module of the backlight unit of the present invention has better heat dissipation efficiency, so it can provide a surface light source with relatively stable quality.

3. In one embodiment, since the light guide plate has a plurality of grooves, a larger-sized heat dissipation element can be selected to further improve the heat dissipation efficiency of the light source module. In this way, the backlight unit can provide a surface light source with more stable quality.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those skilled in the art can make some changes and modifications without departing from the concept and scope of the present invention, so the protection scope of the present invention The scope defined by the appended claims shall prevail.

Claims (10)

1. A light source module, comprising: A circuit board having a patterned metal layer, and the patterned metal layer includes a plurality of connection parts and a pattern circuit, wherein the pattern circuit connects the connection parts; A plurality of light emitting elements are respectively arranged on each of the connecting parts; and At least one heat dissipation element is disposed on the circuit board and contacts the patterned metal layer, and the heat dissipation element is located on the same side of the circuit board as the light emitting element. 2 . The light source module according to claim 1 , wherein the patterned metal layer further comprises at least one heat dissipation pad, the heat dissipation pad is connected to the connecting portion, and the heat dissipation element is disposed on the heat dissipation pad. 3. The light source module according to claim 2, wherein the patterned metal layer further comprises a plurality of the heat dissipation pads, and the heat dissipation pads are respectively connected to one of the connecting parts. 4. The light source module according to claim 3, wherein the light source module comprises a plurality of the heat dissipation elements, and the heat dissipation elements are respectively disposed on the heat dissipation pads. 5. The light source module according to claim 2, wherein the light source module further comprises at least one heat conduction medium, and the heat conduction medium is disposed between the heat dissipation element and the heat dissipation pad. 6. The light source module according to claim 1, wherein the light source module comprises a plurality of the heat dissipation elements, and the heat dissipation elements are respectively arranged between two adjacent light emitting elements. 7. The light source module according to claim 1, wherein the light emitting element is a light emitting diode. 8. The light source module according to claim 1, wherein the heat dissipation element is a metal block. 9. A backlight unit comprising: A light source module, comprising: A circuit board having a patterned metal layer, and the patterned metal layer includes a plurality of connection parts and a pattern circuit, wherein the pattern circuit connects the connection parts; A plurality of light emitting elements are respectively arranged on one of the connection parts; and A plurality of heat dissipation elements are arranged on the circuit board and contact the patterned metal layer, the heat dissipation elements and the light emitting elements are located on the same side of the circuit board, and the heat dissipation elements are respectively arranged on two adjacent light emitting elements between components; and A light guide plate is arranged on one side of the light source module, and one side of the light guide plate has a plurality of grooves and a plurality of light incident surfaces connected between the grooves, and the light incident surfaces are respectively connected to each The light-emitting elements are opposite, and the heat-dissipating elements are respectively located in the grooves. 10. The backlight unit according to claim 9, wherein the patterned metal layer further comprises a plurality of heat dissipation pads, the heat dissipation pads are respectively connected to one of the connection parts, and the heat dissipation element is arranged on the heat dissipation In addition, a plurality of heat conduction media are included between the heat dissipation element and the heat dissipation pad.

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