CN210429875U

CN210429875U - LED packaging structure and backlight module

Info

Publication number: CN210429875U
Application number: CN201921496367.1U
Authority: CN
Inventors: 孙平如; 许文钦; 杨丽敏; 刘涛; 黄鹏
Original assignee: Wuhu Jufei Photoelectric Co Ltd
Current assignee: WUHU JUFEI PHOTOELECTRIC TECHNOLOGY Co.,Ltd.
Priority date: 2019-09-09
Filing date: 2019-09-09
Publication date: 2020-04-28
Anticipated expiration: 2029-09-09

Abstract

The utility model provides a LED packaging structure and backlight module, including the printing opacity LED support, install the LED chip of place the printing opacity LED support bottom, form in the printing opacity LED support inside, and cladding the encapsulation glue film of LED chip, encapsulation glue film and air interface surface are to the sunken face of LED chip indent, the sunken face includes at least one minimum point that corresponds with the LED chip, the minimum point with the distance of flip-chip LED chip top is more than or equal to 0.01 mm; the utility model provides a LED packaging structure adopts the encapsulation glue film of indent structure, changes LED's light path, enlarges LED's wide angle, adopts printing opacity LED support simultaneously for LED chip can follow the support and jet out, enlarges LED's luminous angle to more than 145 degrees, improves ultra-thin backlight unit's equal linearity, reduces LED's use quantity, reduces backlight unit's cost.

Description

LED packaging structure and backlight module

Technical Field

The invention relates to the application field of LEDs, in particular to an LED packaging structure and a backlight module.

Background

At present, the scheme of a common LED bracket, an LED chip and fluorescent powder colloid is basically adopted for an LED for backlight and illumination, the fluorescent powder colloid is basically in a dispensing mode, the fluorescent powder colloid is freely diffused into the LED bracket, and the LED light-emitting angle manufactured by the LED packaging scheme is basically about 120 degrees, as shown in figure 1; with the development of backlight technology, the ultra-thin and HDR display technology is more and more required, the scheme mostly adopts single LED array arrangement without LENS, and the requirement of uniform illumination on a target surface is difficult to meet for the LED with a light-emitting angle of 120 degrees.

Disclosure of Invention

The invention provides an LED packaging structure and a backlight module, which mainly solve the technical problems that: the LED light emitting angle of the existing LED package cannot meet the problem of uniform illumination of a target surface required by the requirements of ultrathin and HDR display technologies.

To solve the above technical problem, the present invention provides an LED package structure, including: the LED light source comprises a light-transmitting LED bracket, an LED chip arranged at the bottom of the light-transmitting LED bracket, and a packaging adhesive layer formed in the light-transmitting LED bracket and coating the LED chip;

the packaging structure comprises an LED chip, a packaging adhesive layer and an air interface, wherein the packaging adhesive layer and the air interface surface are concave surfaces which are concave towards the LED chip, each concave surface comprises at least one lowest point corresponding to the LED chip, and the distance between each lowest point and the top of the LED chip is larger than or equal to 0.01 mm.

Optionally, the material of the light-transmitting LED support is a transparent material.

Optionally, the light-transmitting LED support includes a white material thereon.

Optionally, the flip LED chip fixes the bottom of the light-transmitting LED support in a die bonding or eutectic manner.

Optionally, the lowest point of the recessed surface is located right above the LED chip, and the encapsulation adhesive layer is symmetrical about the lowest point.

Optionally, the concave surface is formed by an arc line or a straight line.

Optionally, the arc is a concave arc towards the LED chip, or a convex arc towards the air surface.

Optionally, the arc range is not more than between two straight lines formed by the left end and the right end of the LED chip and the top of the light-transmitting LED support.

Optionally, the recessed surface of the encapsulation adhesive layer includes at least two lowest points located on the same horizontal plane, and the at least two lowest points form a lowest plane of the recessed surface.

Furthermore, the invention also provides a backlight module which comprises the LED packaging structure.

Advantageous effects

The invention provides an LED packaging structure and a backlight module, which comprise a light-transmitting LED bracket, an LED chip arranged at the bottom of the light-transmitting LED bracket, and a packaging adhesive layer formed in the light-transmitting LED bracket and coating the LED chip, wherein the interface surface of the packaging adhesive layer and the air is a concave surface which is concave towards the LED chip, the concave surface comprises at least one lowest point corresponding to the LED chip, and the distance between the lowest point and the top of the LED chip is more than 0.01 mm; the LED packaging structure provided by the invention adopts the packaging adhesive layer with the concave structure, changes the light path of the LED, enlarges the light-emitting angle of the LED, and is suitable for different requirements through the concave packaging adhesive layers with various degrees; meanwhile, the light-transmitting LED support is adopted, so that the LED chips can be ejected from the support, the light-emitting angle of the LED is enlarged to be more than 145 degrees, the uniformity of the ultrathin backlight module is improved, the use number of the LED is reduced, and the cost of the backlight module is reduced.

Drawings

Fig. 1 is a schematic structural diagram of an LED package structure provided in the prior art;

fig. 2 is a first schematic structural diagram of an LED package structure according to a first embodiment of the present invention;

fig. 3 is a schematic structural diagram of an LED package structure according to a first embodiment of the present invention;

fig. 4 is a schematic structural diagram three of an LED package structure according to a first embodiment of the present invention;

fig. 5 is a fourth schematic structural diagram of an LED package structure according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of an LED package structure according to a first embodiment of the present invention;

fig. 7 is a sixth schematic structural diagram of an LED package structure according to an embodiment of the present invention;

fig. 8 is a seventh schematic structural diagram of an LED package structure according to an embodiment of the present invention;

fig. 9 is an eighth schematic structural diagram of an LED package structure according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram nine of an LED package structure according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of an LED package structure according to an embodiment of the present invention;

fig. 12 is an eleventh schematic structural diagram of an LED package structure according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of an LED package structure according to a second embodiment of the present invention;

fig. 14 is a schematic structural diagram of another LED package structure according to a second embodiment of the present invention.

Detailed Description

In order that the contents of the present invention will be more readily understood, the present invention will now be described in further detail with reference to the accompanying drawings by way of specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The first embodiment is as follows:

the light emitting angle of the conventional LED package structure is 120 degrees, which cannot meet the requirements of ultra-thin and HDR display technologies, and in order to solve the above problems, the present embodiment provides an LED package structure, please refer to fig. 2, the LED package structure includes a light-transmitting LED support 101, an LED chip 102 disposed on a base of the light-transmitting LED support 101, and a package adhesive layer 103 formed inside the light-transmitting LED support 101 and covering the LED chip 102, a boundary surface between the package adhesive layer 103 and air is a concave surface that is concave towards the LED chip 102, wherein the package adhesive layer 103 covering the LED chip 102 can enable light emitted by the LED chip 102 to pass through the package adhesive layer 103 and be refracted, and a light path can be changed through the package adhesive layer 103 having the concave structure, so that the light is refracted to the LED support, the present embodiment employs the light-transmitting LED support 101, that is light emitted from the light-transmitting LED support 101, therefore, the light emitting angle of the LED is expanded from 120 degrees of positive light emission to 145 degrees or more of positive light emission and side light emission. It should be noted that the recessed surface of the encapsulant layer 103 includes at least one lowest point corresponding to the LED chip 102, for example, at least 2 lowest points (located on the same horizontal plane), 1 lowest point in fig. 2, and the like, and the distance between the lowest point and the top of the LED chip 102 is greater than or equal to 0.01mm, so that the upper surface of the LED chip 102 is the encapsulant layer 103, and the recessed degree is different according to the difference between the distance between the lowest point and the top of the LED chip 102, and the recessed encapsulant layer 103 with various degrees is suitable for different requirements. For example, the distance between the lowest point and the top of the LED chip 102 is small as the height of the light-transmitting LED support 101 is higher; when the height of the light-transmitting LED support 101 is 0.6T (0.6mm), the distance between the lowest point and the top of the LED chip 102 is 0.03 mm; when the height of the light-transmitting LED support 101 is 1.6T, the distance between the lowest point and the top of the LED chip 102 is 0.01 mm.

At present, the LED package mostly uses an opaque material with good thermal conductivity as a support, and in this embodiment, the support is made of a transparent material, that is, the material of the light-transmitting LED support 101 includes a transparent material, including but not limited to transparent alumina ceramic, aluminum nitride ceramic, silicon oxide, glass or resin. The light-transmitting LED support 101 in this embodiment may also be made of a common material, in which case the light-transmitting LED support 101 further includes a white material, and the common LED support is coated with the white material, so that the support has light transmittance, where the white material includes, but is not limited to, polyether or polyester polyol.

In this embodiment, the light-transmissive LED support 101 includes a base and a wall, and the shape thereof includes, but is not limited to, a bowl shape, a square shape; in order to avoid the light emission of the LED from the back surface, only the enclosing wall in the light-transmitting LED support 101 has light-transmitting property, so when the light-transmitting LED support 101 is made of a transparent material, the base and the enclosing wall may not be integrally formed, and the enclosing wall made of the transparent material and the base made of a common material are combined to form the light-transmitting LED support 101; the base and the enclosing wall can also be integrally formed, and only the base of the light-transmitting LED bracket 101 is coated with white materials. In some embodiments, both the base and the perimeter walls of the light-transmissive LED support 101 may be light-transmissive, depending on the actual requirements of the product.

In this embodiment, the LED chip 102 is mounted on the base of the LED support 101 through die bonding or eutectic method, the LED chip 102 is flipped over to an intermediate position on the base, for example, as shown in fig. 3, the base includes a support positive electrode 1011 and a support negative electrode 1012, and the positive and negative electrodes of the LED chip 102 are electrically connected to the support positive electrode 1011 and the support negative electrode 1012 through a conductive adhesive 1013 (e.g., silver adhesive).

It should be noted that the encapsulation adhesive layer 103 of the present embodiment forms a concave surface from the top of the light-transmitting LED support 101 to the inside of the LED chip 102, that is, the concave surface is from the top of the two side walls to the base, and the height of the encapsulation adhesive layer 103 inside the light-transmitting LED support 101 is lower than that of the two side encapsulation adhesive layers 103 in contact with the light-transmitting LED support 101; as shown in fig. 2 and 3, the height of the two side packaging adhesive layers 103 contacting the top of the light-transmitting LED support 101 is the same as the height of the light-transmitting LED support 101, and the height of the inner packaging adhesive layer 103 is gradually lower than the height of the light-transmitting LED support 101 to form a concave surface with a concave structure. In some embodiments, the encapsulating adhesive layer 103 may also be recessed from a height lower than the top of the light-transmissive LED support 101, as shown in fig. 4, the height of the encapsulating adhesive layer 103 on two sides contacting the wall of the light-transmissive LED support 101 is lower than the height of the top of the light-transmissive LED support 101.

In this embodiment, the encapsulating adhesive layer 103 includes at least one lowest point, for example, when the encapsulating adhesive layer includes one lowest point, the LED encapsulating structure is as shown in fig. 2 and 3, the lowest point of the encapsulating adhesive layer 103 in this embodiment is located right above the LED chip 102, that is, the lowest point of the encapsulating adhesive layer 103 and the center point of the LED chip 102 are located on the same horizontal line, so that the forward light emitting effect of the LED chip 102 is better; preferably, the encapsulation adhesive layer 103 is symmetrical around the lowest point of the concave surface, so that the lateral light emitted by the LED is uniform from side to side, as shown in fig. 3. In some embodiments, the concave shape of the concave surface may also be adjusted according to actual product requirements, for example, as shown in fig. 5, the lowest point of the concave surface of the encapsulating glue layer 103 is located on the left side of the center point of the LED chip 102, and the encapsulating glue on the right side of the LED chip 102 is more than that on the left side, so that the LED chip 102 emits light on the right side intensively.

It should be noted that the concave surface of the encapsulating adhesive layer 103 in this embodiment may be formed by an arc, which may be an arc concave towards the LED chip 102, as shown in fig. 3, and in some embodiments, the arc may also be an arc convex towards the air surface, as shown in fig. 6; it should be noted that, no matter whether the arc of the concave surface is concave or convex, the range of the arc does not exceed the range between two straight lines formed by the left and right ends of the LED chip 102 and the top of the light-transmitting LED support 101, as shown in fig. 7, the range of the arc 702 of the concave surface of the encapsulating adhesive layer 103 does not exceed the range between two straight lines 701, and the range between the left and right ends of the LED chip 102 and the straight lines 701 formed by the top of the light-transmitting LED support 101.

In some embodiments, the recessed surface of the encapsulating adhesive layer 103 may also be formed by a straight line, as shown in fig. 8, and the recessed surface has an inverted triangle shape.

In the present embodiment, the recessed surface of the encapsulant layer 103 shown in fig. 2-7 is illustrated as a lowest point, where the recessed surface includes at least two lowest points, the recessed surface of the encapsulant layer 103 includes at least two lowest points located on the same horizontal plane, and the at least two lowest points form a lowest plane of the recessed surface, as shown in fig. 9, the encapsulant layer 103 is recessed downwards from the top of the light-transmissive LED support 101 in an arc shape 901, the lowest encapsulant layer 103 located above the LED chip 102 is a straight line 902, so that the encapsulant layer 103 has an arc-shaped inverted trapezoid structure, and a portion of the straight line 902 is regarded as a combination of a plurality of lowest points 903. The length of the straight line 902 may be smaller than the LED chip 102 or the same as the LED chip 102.

In some embodiments, as shown in fig. 10, the recessed surface of the encapsulating adhesive layer 103 is formed by straight lines, forming an inverted trapezoid shape; as shown in fig. 11, the concave surface of the encapsulating adhesive layer 103 is formed by a convex arc line and a lowest plane.

In some embodiments, when the encapsulant layer 103 includes at least two lowest points located at the same horizontal plane, the encapsulant layer 103 includes at least two concave arcs with the same structure, as shown in fig. 12, the encapsulant layer 103 located inside the light-transmissive LED support 101 includes two consecutive concave arcs 1201, and the lowest points 1202 corresponding to the two arcs may be located above the LED chip 102 at the same time, or any one of the lowest points 1202 may be located above the LED chip.

In this embodiment, the encapsulation glue layer 103 includes phosphor glue, and is more preferable, and the encapsulation glue is the light transmissivity, transparent silica gel or epoxy that stability is good to mix with phosphor powder and form, make this LED packaging structure have high refracting index and high luminousness, can play the luminous flux that the protection LED chip 102 increased LED, viscosity is little, easily takes off the bubble, is fit for embedment and compression molding, makes LED have better durability and reliability.

This embodiment provides a LED packaging structure, including the printing opacity LED support that has the light transmissivity, the flip-chip is at the LED chip of printing opacity LED support bottom, including the encapsulation glue film in printing opacity LED support inside, this encapsulation glue film cladding flip-chip LED chip, its one side of keeping away from the flip-chip LED chip sets up to the arc of caving in to the flip-chip LED chip, the encapsulation glue film through the interior concave structure has changed the light line route, make light roll over to the printing opacity LED support, jet out in the printing opacity LED support, thereby enlarge LED's luminous angle, if from the 120 degrees expansion of positive luminescence to positive luminescence, the side is luminous more than 145 degrees.

Example two:

the present embodiment provides a specific LED package structure, as shown in fig. 13 and 14, the LED package structure includes a light-transmitting LED support 101, a flip LED chip 102 and a package adhesive layer 103, wherein the flip LED chip 102 is flip-mounted on the bottom of the light-transmitting LED support 101 through a conductive adhesive and is electrically connected to the light-transmitting LED support 101; the interface surface of the packaging adhesive layer 103 and the air is a concave surface concave towards the flip-chip LED chip 102, and in fig. 13, the concave surface is formed by a concave arc and a straight line to form an inverted trapezoidal arc structure; in fig. 14, the concave surface is formed by an upwardly convex arc shape; the light path of the LED can be changed by optically designing a mold to mold the package adhesive layer 103, so as to shape the package adhesive layer 103 with a concave structure.

In this embodiment, the light-transmitting LED support 101 includes a base 1011 and a wall 1012, the base 1011 and the wall 1012 combine to form the bowl-shaped light-transmitting LED support 101, and the base 1011 is made of an opaque material with good thermal conductivity, such as copper, aluminum, alumina ceramic, etc.; the enclosure walls 1012 are made of transparent materials, such as transparent alumina ceramics, aluminum nitride ceramics, silicon oxide, glass or resin. In some embodiments, the wall 1012 may be made of the same material as the base 1011, in which case the wall 1012 and the base 1011 may be integrally formed, and the wall 1012 on the formed light-transmissive LED support 101 is coated with white (polyether or polyester polyol) to make the support light-transmissive.

In this embodiment, the encapsulation adhesive layer 103 is recessed from the top of the light-transmitting LED support 101 to the flip-chip LED chip 102, i.e. recessed from the top of the perimeter 1012 at two sides to the base 1011, the height of the encapsulation adhesive layer 103 contacting with the top of the perimeter 1012 is the same as the height of the perimeter 1012, the height of the inner encapsulation adhesive layer 103 is lower than the height of the top of the perimeter 1012, and the two sides are gradually lowered towards the middle to form a recessed structure, wherein the lowest point of the encapsulation adhesive layer 103 is located right above the flip-chip LED chip 102, and the encapsulation adhesive layer 103 is in a bilateral symmetry structure with the flip-chip LED chip 102 as the center, so. It should be noted that the distance between the lowest point of the encapsulating adhesive layer 103 and the top of the flip-chip LED chip 102 in this embodiment is greater than or equal to 0.01 mm.

It should be noted that the encapsulation adhesive in this embodiment is transparent silica gel or epoxy resin with good light transmittance and stability, and is formed by mixing with phosphor, so that the flip LED chip 102 encapsulation body has high refractive index and high light transmittance, can play a role in protecting the flip LED chip 102, and has the advantages of increasing the luminous flux of the LED, being small in viscosity, easy to bubble, suitable for encapsulation and compression molding, and the like, so that the LED has better durability and reliability.

This embodiment provides a concrete LED packaging structure, adopt transparent material's LED support or scribble the LED support of white material, flip-chip LED chip flip-chip is in the bottom of LED support, form through mixing by phosphor powder and transparent silica gel or epoxy and encapsulate, through a mould of optical design, carry out the mould pressing to the encapsulation glue film, mould the shape of the encapsulation glue film of a indent structure, change LED's light path, enlarge LED's luminous angle, enlarge ordinary LED's luminous angle from 120 degrees to more than 145 degrees, can improve ultra-thin backlight unit's uniformity linearity, reduce LED's use quantity, reduce backlight unit's cost.

Example three:

the present embodiment provides a backlight module, including the LED package structure in the first embodiment or the second embodiment, specifically, the LED package structure includes: the LED light source comprises a light-transmitting LED bracket, an LED chip arranged at the bottom of the light-transmitting LED bracket, and a packaging adhesive layer formed in the light-transmitting LED bracket and coating the LED chip; the packaging glue layer and air interface surface is a concave surface which is concave towards the LED chip, the concave surface comprises at least one lowest point corresponding to the LED chip, and the distance between the lowest point and the top of the LED chip is more than or equal to 0.01 mm.

It should be understood that the LED package structure provided in this embodiment can be applied to various light emitting fields, for example, it can be manufactured into a backlight module applied to a display backlight field (such as a backlight module of a terminal of a television, a display, a mobile phone, etc.). It can be applied to a backlight module at this time. The LED lamp can also be applied to the key backlight field, the shooting field, the household lighting field, the medical lighting field, the decoration field, the automobile field, the traffic field and the like. When the LED backlight source is applied to the key backlight field, the LED backlight source can be used as a key backlight light source of mobile phones, calculators, keyboards and other devices with keys; when the camera is applied to the field of shooting, a flash lamp of a camera can be manufactured; when the lamp is applied to the field of household illumination, the lamp can be made into a floor lamp, a table lamp, an illuminating lamp, a ceiling lamp, a down lamp, a projection lamp and the like; when the lamp is applied to the field of medical illumination, the lamp can be made into an operating lamp, a low-electromagnetic illuminating lamp and the like; when the decorative material is applied to the decorative field, the decorative material can be made into various decorative lamps, such as various colored lamps, landscape illuminating lamps and advertising lamps; when the material is applied to the field of automobiles, the material can be made into automobile lamps, automobile indicating lamps and the like; when the lamp is applied to the traffic field, various traffic lights and various street lamps can be manufactured. The above applications are only a few exemplified applications of the present embodiment, and it should be understood that the application of the LED package structure is not limited to the above exemplified fields.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An LED package structure, comprising:

the LED light source comprises a light-transmitting LED bracket, an LED chip arranged at the bottom of the light-transmitting LED bracket, and a packaging adhesive layer formed in the light-transmitting LED bracket and coating the LED chip;

2. The LED package structure of claim 1, wherein the material of the light-transmissive LED support is a transparent material.

3. The LED package structure of claim 1, wherein said light transmissive LED support includes a white material thereon.

4. The LED package structure of claim 1, wherein the LED chip is fixed to the bottom of the light-transmissive LED support by die bonding or eutectic bonding.

5. The LED package structure of any one of claims 1-4, wherein the lowest point of the recessed surface is located directly above the LED chip, and the encapsulant layer is symmetrical about the lowest point.

6. The LED package structure of claim 5, wherein the recessed surface is formed by an arc or a straight line.

7. The LED package structure of claim 6, wherein the arc is concave towards the LED chip or convex towards the air surface.

8. The LED package structure of claim 7, wherein the arc does not extend beyond two straight lines between the two ends of the LED chip and the top of the light-transmissive LED support.

9. The LED package structure of claim 8, wherein the recessed surface of the encapsulant layer comprises at least two lowest points located at a same horizontal plane, the at least two lowest points forming a lowest plane of the recessed surface.

10. A backlight module comprising the LED package structure according to any one of claims 1 to 9.