WO2015172550A1

WO2015172550A1 - Led lamp and manufacturing process therefor and backlight module

Info

Publication number: WO2015172550A1
Application number: PCT/CN2014/092843
Authority: WO
Inventors: 许斌; 唐加良; 袁永刚
Original assignee: 苏州东山精密制造股份有限公司
Priority date: 2014-05-12
Filing date: 2014-12-02
Publication date: 2015-11-19
Also published as: CN103939810A

Abstract

An LED lamp and a manufacturing process therefor and a backlight module. The LED lamp comprises a substrate (101), an LED chip (102) fixed on the substrate (101) and fluorescent glue (104) coating the LED chip (102) and bonded to the substrate (101). The substrate (101) comprises a conductive layer, and an electrode of the LED chip (102) is connected to an electrode on the conductive layer via a conductive wire (103). A bottom surface of the LED chip (102) is connected to the substrate (101), a top surface opposite to the bottom surface of the LED chip (102) is a light-emitting surface, and light emitted by the top surface of the LED chip (102) is emitted outwards via the fluorescent glue (104).

Description

LED lamp and manufacturing process thereof and backlight module

Technical field

The invention relates to the field of illumination, in particular to an LED lamp, a manufacturing process thereof and a backlight module.

Background technique

Existing electronic devices (including mobile phones, IPads, etc.) backlights generally use side-emitting particles (such as 3806 LED strips) as mainstream products. The manufacturing process of the existing mobile phone backlight module is as follows: Step 1: Take a bracket (the material of the bracket is usually PPC, PPA bracket, etc.), and fix the chip on the bracket; Step 2: Conduct conductive wire welding after the chip is fixed, as long as The connection between the bracket and the chip is turned on; Step 3: Dispensing after the welding is completed, the phosphor and the glue mixture are injected into the cavity of the stent during dispensing, and the baking is completed into pellets; Step 4: cutting the pellets, The particles on the whole piece of the stent are cut into single LED particles; Step 5: test and package the single LED particles; Step 6: SMT (Surface Mounted Technology, SMT for short), and patch the single LED particles to the FPCB (Flexible Printed Circuit Board (FPCB or FPC for short) forms a backlight strip on the light bar: Step 7: The backlight strip is assembled on the backlight module of the mobile phone to form a finished backlight product. In the prior art, the entire backlight module is completed by a fixed chip, a conduction chip, a dispensing molding, a granulation, a packaging, a patch, and an assembly.

The prior art mobile phone backlight module has the following defects: (1) the existing mobile phone backlight module is designed to be side-emitting, all uses 3806 particles, and a single particle needs to be patched onto the FPCB light bar, and the particle arrangement is small, and now Some particles are cup-shaped, and the overall glazing surface will be reduced, which results in low overall luminous efficiency of the backlight module; (2) the prior art process has a long process and prolongs the output time of the finished product; (3) In the prior art, solder paste, FPCB light bar and patch device are needed, which increases the cost; (4) in the prior art process, the chip is first placed on the bracket, and then cut into a single particle together with the bracket, and then A single particle patch is formed on the FPCB light bar to form a backlight strip. Thus, due to the thick thickness of the backlight strip, the overall thickness of the finished backlight product is thicker and cannot break through the ultra-thin type. For example, the overall thickness of the 3806 particle is 0.6 mm. Between -0.63mm, plus the thickness of the PFCB light bar is 0.1mm, which determines the thickness of the mobile phone, so there is no need for ultra-thin breakthrough. If the thickness is reduced, the light-emitting area is reduced, resulting in less brightness. .

Therefore, it is necessary to further improve the defects in the prior art.

Summary of the invention

One of the objects of the present invention is to provide an LED lamp which has a good light-emitting effect and a thin overall thickness.

Another object of the present invention is to provide a method for manufacturing an LED lamp, which has a simple process, and the obtained LED particles are front side illumination, and the luminous surface effect is improved by 3-4 times, and the LED strip of the invention is provided. The size is reduced, resulting in a reduction in the overall thickness of the product.

It is still another object of the present invention to provide a backlight module.

According to an aspect of the present invention, an LED lamp of the present invention includes:

a substrate comprising a conductive layer;

An LED chip fixed on the substrate, wherein an electrode is connected to an electrode on the conductive layer through a conductive line, a bottom surface of the LED chip is in contact with the substrate, and a top surface of the LED chip opposite to the bottom surface is a light emitting surface ;

A fluorescent glue covering the LED chip and bonded to the substrate, and light emitted from a top surface of the LED chip is emitted outward through the fluorescent glue.

As a preferred embodiment of the present invention, a plurality of LED chips are fixed on the substrate, and the LED chips are fixed on one side of the substrate and form one or more rows.

As a preferred embodiment of the present invention, the fluorescent glue has an isosceles trapezoidal shape, a square shape or a semicircular shape.

As a preferred embodiment of the present invention, the width of the substrate is equal to the coverage width of the fluorescent glue on the substrate.

As a preferred embodiment of the present invention, the conductive layer of the substrate further includes an external electrode, and the external power source supplies power to the LED chip through the external electrode to cause the LED chip to emit light.

According to another aspect of the present invention, there is provided a manufacturing process of an LED lamp, comprising:

Providing a substrate, the substrate comprising a conductive layer;

Fixing a plurality of LED chips on one side of the substrate, the LED chips are formed in one or more rows, a bottom surface of the LED chip is in contact with the substrate, and a top surface of the LED chip opposite to the bottom surface a luminous surface;

Connecting the positive and negative electrodes of the top surface of the LED chip to the electrodes on the conductive layer through conductive wires;

The fluorescent glue is pressed onto the substrate by molding, so that the fluorescent glue covers the LED chip, and light emitted from the top surface of the LED chip is emitted outward through the fluorescent glue;

The stamped substrate is cut into a plurality of LED strips or a plurality of LED lamp particles.

Further, the cross section of the fluorescent glue is an isosceles trapezoid, a square or a semicircle.

Further, the width of the substrate is equal to the coverage width of the fluorescent glue on the substrate.

Further, each of the LED strips includes a plurality of individual LED particles, and the plurality of LED particles are connected in series on the conductive layer.

Further, the cut LED light bar and the light guide plate are assembled into a backlight module.

According to another aspect of the present invention, a backlight module includes a reflective sheet, an LED light strip, a light guide plate, and a diffusion plate, and the LED light bar is located between the reflective sheet and the light guide plate, and is located at the a side edge of the light guide plate, the diffusion plate is placed in close proximity to the light guide plate, the LED light bar includes a conductive chip substrate, an LED chip fixed on the substrate, and the LED chip is coated and bonded a fluorescent glue on the substrate, wherein an electrode of the LED chip is connected to an electrode on the conductive layer through a conductive line, a bottom surface of the LED chip is connected to the substrate, and a top surface of the LED chip opposite to the bottom surface As a light emitting surface, light emitted from a top surface of the LED chip is emitted outward through the fluorescent glue.

The top surface of the fluorescent glue of the LED strip is next to the light guide such that the light emitting surface of the LED chip of the LED strip directly faces the light guide.

Further, the substrate includes a metal layer and a resin layer, and the metal layer is the conductive layer.

Further, the width of the LED light bar is equal to the coverage width of the fluorescent glue on the substrate.

Further, the LED strip has a thickness of 0.3-0.5 mm.

Further, the plurality of LED chips are arranged in a row on the substrate, the fluorescent glue is separately coated on the periphery of each LED chip, or the fluorescent glue is integrally coated on the row of LED chips. The periphery.

Further, the reflection sheet, the light guide plate and the diffusion plate are all flat, and they are placed in parallel with each other.

The backlight module includes an outer frame, and the reflective sheet, the LED light strip, the light guide plate and the diffusion plate are disposed in the outer frame.

Advantageous Effects of Invention: Compared with the prior art, the present invention has the following advantages:

(1) The LED lamp of the present invention has a top light emission, a small pitch, no cup, reduces the auxiliary cup frame, effectively utilizes the space, increases the number of products, increases the light-emitting area, and uses the entire light bar as a light-emitting surface. Thereby, the brightness of the whole screen of the backlight product is improved by about 3-4 times that of the conventional backlight, and the problem of the user using the screen is solved;

(2) The invention directly designs the circuit on the granular substrate, reduces the assembly process of the SMT, has simple process, and reduces the cost;

(3) The thickness of the light bar can be controlled to 0.3-0.5 mm, so that the thickness of the ultra-thin mobile phone can be solved, and the luminous effect is improved;

(4) The invention has a wide range of use and can be used for modules such as mobile phones, car navigation and IPad.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention, Those skilled in the art can also obtain other drawings based on these drawings without paying any inventive labor. among them:

1 is a flow chart showing a manufacturing process of an LED lamp of the present invention;

2A is a schematic structural view of a substrate used in the present invention;

2B is a schematic structural view of a solid crystal step in a manufacturing process flow of the LED lamp of the present invention;

2C is a schematic structural view of a wire bonding step in a manufacturing process flow of the LED lamp of the present invention;

2D (1) is a schematic structural view of a stamping step in a manufacturing process of the LED lamp of the present invention in a specific embodiment;

2D (2) is a schematic structural view of a stamping step in another manufacturing embodiment of the manufacturing process of the LED lamp of the present invention;

2D(3) is a schematic structural view showing a step of a stamper in a manufacturing process flow of the LED lamp of the present invention in still another specific embodiment;

2E is a schematic structural view of a cutting step in a manufacturing process flow of the LED lamp of the present invention;

3 is a schematic structural view of a backlight module of the present invention;

4 is a schematic view showing the assembled structure of the backlight module of the present invention.

detailed description

The present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

The term "one embodiment" or "an embodiment" as used herein refers to a particular feature, structure, or characteristic that can be included in at least one implementation of the invention. The appearances of the "in one embodiment", "a" or "an"

Please refer to FIG. 1 , which is a flow chart of a manufacturing process of the LED lamp of the present invention. Please refer to FIG. 2A-2E. FIGS. 2A-2E are diagrams showing the corresponding products of the manufacturing process of the LED lamp of the present invention. The invention performs the fixing chip on the substrate, and after the chip is fixed, the conductive wire is welded, and after the welding is completed, the pressing mold is performed, and the phosphor powder and the glue mixture are injected into the cavity during the molding, the pellet is formed by baking, and the light bar is cut and assembled. Backlight. The entire backlight module is completed by fixing the chip, turning on the chip, molding, cutting into a light bar, and assembling. The manufacturing process of the LED lamp of the present invention is described below, which specifically includes the following steps:

Step S110: providing a substrate 101. Please refer to FIG. 2A , which is a schematic structural view of a substrate used in the present invention. In this embodiment, the substrate 101 includes a conductive layer (not shown) on which a chip is mounted, and an electrode is disposed on the conductive layer. The substrate 101 in the present invention includes a metal layer and a resin layer, and the metal layer is the conductive layer. In the present invention, the thickness of the conductive layer is not limited, and may be determined according to actual conditions. It should be noted that since the conductive layer is an extremely thin film, the conductive layer is not shown in the substrate of FIGS. 2A-2E in the present invention, but this does not mean that the conductive layer is not present. In the present invention, the size and shape of the substrate 101 are not limited, and the maximum required utilization of the substrate 101 can be determined according to the actual number of LED strips and LED chips required. In the present invention, the conductive layer of the substrate 101 further includes an external electrode (not shown) through which the external power source supplies power to the LED chip 102 to cause the LED chip 102 to emit light.

Step S120: solid crystal. Please refer to FIG. 2B , which is a structural schematic diagram of a solid crystal step in the manufacturing process of the LED lamp of the present invention. The die bonding is to attach a plurality of chips 102 to one side of the substrate 101. First, the substrate 101 is placed on a bottom plate carrier (not shown) with its side facing up, passing back The flow soldering process fixes the chip 102 on the conductive layer on the substrate 101 to complete the die bonding process. The LED chips 102 are formed in one or more rows. The electrodes of the LED chips 102 are connected to the electrodes on the conductive layer through the conductive lines 103. The bottom surface of the LED chips 102 is connected to the substrate 101. The LED chips are connected. The top surface opposite to the bottom surface is a light emitting surface. In other embodiments, there is no limitation on the number and arrangement of the LED chips 102 on the substrate 101.

Step S130: welding wire. Please refer to FIG. 2C , which is a structural schematic diagram of a wire bonding step in the manufacturing process flow of the LED lamp of the present invention. The bonding wire is a connection between the conduction chip 102 and the substrate 101. First, the substrate 101 is placed on a substrate carrier (not shown) such that the side having the LED chip 102 faces upward, and the positive and negative electrodes of the top surface of the LED chip 102 are electrically connected to the The electrodes on the conductive layer are connected, and the LED chip 102 and the electrode are electrically connected by the conductive line 103 to complete the bonding wire. The electrode on the conductive layer is electrically connected to an external power source (not shown) through a wire, and the LED chip 102 is turned on by an external power source. The present invention directly designs circuits on the substrate 101 to reduce processes, reduce cost, and reduce the thickness of the LED particles.

Step S140: stamping. Please refer to FIG. 2D(1), which is a schematic structural view of a stamping step in a manufacturing process of the LED lamp of the present invention in a specific embodiment. The stamper is formed by injecting a mixture of the fluorescent glue 104 into a cavity. The fluorescent glue 104 is a mixture of a phosphor and a glue. The fluorescent glue 104 is pressed onto the substrate 101 by molding, so that the fluorescent glue 104 covers the LED chip 102, and light emitted from the top surface of the LED chip is emitted outward through the fluorescent glue. In this embodiment, a plurality of LED chips 102 are mounted on the substrate 101, and the LED chips 102 are fixed on one side of the substrate 101 and formed in one or more rows. The stamper molds a plurality of rows of LED chips on the substrate 101. The fluorescent glue is placed in a cavity of an upper mold (not shown) and a lower mold (not shown), and the substrate 101 to which the conductive wire 103 is connected is fed into the cavity of the upper mold and the lower mold of the molding machine. After the mold is heated by the device, the fluorescent glue is solidified, and then the device automatically transfers the molded substrate 101 to complete the stamping. Please refer to FIG. 2D(2), which is a structural schematic diagram of a stamping step in another manufacturing embodiment of the manufacturing process of the LED lamp of the present invention. In this embodiment, the LED chips on the substrate 101 are individually stamped and formed into a single LED particle 105. Please refer to FIG. 2D(3), which is a structural schematic diagram of a stamping step in a manufacturing process of the LED lamp of the present invention in still another specific embodiment. In this embodiment, all of the LED chips 102 on the substrate 101 are subjected to a full pressure mode and formed into integral LED particles 106. The invention can be based on the mold side Different types of molds and compression molding processes are selected.

Step S150: cutting. Please refer to FIG. 2E , which is a structural schematic diagram of a cutting step in the manufacturing process flow of the LED lamp of the present invention. The cutting is to cut the entire substrate 101 into a plurality of LED strips 200 of corresponding thickness or a plurality of LED lamp particles. In this embodiment, the substrate 101 is cut into a plurality of LED strips 200 along a row of the substrate 101. Each LED strip 200 includes a plurality of individual LED particles 108 that are connected in series on the conductive layer. When the LED chip 102 emits light, light is transmitted through the fluorescent glue 104. The present invention can control the thickness of the LED light bar 200 to 0.3-0.5 mm as needed. Moreover, in the present invention, the substrate 101 is cut to be equal to or similar to the coverage width of the fluorescent glue on the substrate, so that the limitation of the ultra-thin mobile phone can be broken. Moreover, the LED light bar 200 of the present invention has a top light emission, and the pitch is small so that the entire LED light bar 200 is a light emitting surface, thereby improving the light effect by 1.5-2 times.

Step S160: assembly. In an embodiment, the step S150 further includes the step S160 assembly. Please refer to FIG. 3 , which is a structural diagram of a backlight module of the present invention. The cut LED strip 200 and the light guide plate 301 are assembled into a backlight module. The LED light bar of the present invention reduces the FPCB light bar in the background art, which not only reduces the production cost, but also reduces the thickness of the entire LED light bar.

Please refer to Figure 3 and Figure 4. 4 is a schematic structural view of a backlight module of the present invention; and FIG. 4 is a schematic view showing an assembly structure of a backlight module according to the present invention. The backlight module includes a reflective sheet (not shown), an LED strip 200, a light guide plate 301, and a diffusion plate (not shown). The LED light bar 200 is located between the reflective sheet 304 and the light guide plate 301 and is located at one side edge of the light guide plate 301 . The diffusion plate is placed in close proximity to the light guide plate 301 . 2A-2E, the LED light bar 200 includes a conductive layer substrate 101, an LED chip 102 fixed on the substrate 101, and fluorescent light that is coated on the LED chip 102 and bonded to the substrate 101. The glue 104 is connected to the electrode on the conductive layer via a conductive line 103. The bottom surface of the LED chip 102 is connected to the substrate 101. The top of the LED chip 102 opposite to the bottom surface The surface is a light-emitting surface, and light emitted from the top surface of the LED chip 102 is emitted outward through the fluorescent glue 104.

The top surface of the fluorescent glue 104 of the LED light bar 200 is adjacent to the light guide plate 301 such that the light emitting surface of the LED chip of the LED light bar 200 faces the light guide plate 301. It should be noted that, in the present invention, the fluorescent glue 104 and its coated LED chip 102 are collectively referred to as LED particles 108. In this embodiment, The number of the LED light bars 200 is one. In other embodiments, the number of the LED light strips 200 may be more than one, and the specific quantity may be determined according to actual conditions.

In this embodiment, the shape of the fluorescent glue 104 is an isosceles trapezoid, which can ensure more light passes through the light guide plate 301, greatly improving the light effect and enhancing the brightness of the entire product. In other embodiments, the shape of the LED particles 108 may also be square or semi-circular. The mixing ratio of the phosphor and the glue is not limited in the present invention, and may be determined according to actual conditions.

In this embodiment, in order to ensure the independence of the illumination of each LED chip 102, the fluorescent glue 104 is separately coated on the periphery of each LED chip 102. In other embodiments, the fluorescent glue 104 may also be The whole is covered on the periphery of the row of LED chips 102.

Referring to FIG. 2E, in the embodiment, the width of the LED light bar 200 is equal to the coverage width of the fluorescent glue 104 on the substrate 101. This saves the substrate and reduces the width of the LED strip 200, thereby reducing the thickness of the entire backlight module. In this embodiment, the thickness of the LED light bar 200 is 0.3-0.5 mm, which reduces the overall thickness of the backlight module, and greatly saves production costs.

Referring to FIG. 4, the backlight module of the present invention further includes an outer frame including a metal frame 303 and a plastic frame 302. The reflection sheet 304, the light guide plate 301, and the diffusion plate are each in the form of a flat plate, and they are placed in parallel with each other. The reflection sheet 304, the LED light bar 200, the light guide plate 301, and the diffusion plate are disposed in the outer frame. The diffusion sheet includes a middle diffusion sheet 305 and an upper diffusion sheet 306. The plastic frame 302 is engaged with the metal frame 303, and then the reflective sheet 304 is engaged with the plastic frame 302, and the LED light bar is correspondingly mounted on one side of the plastic frame. The light guide plate 301 The light guide plate is disposed on the side of the reflective strip 304 opposite to the LED strip, and then the middle diffuser 305 and the upper diffuser 306 are sequentially mounted on the outer side of the plastic frame, the metal frame 303 and the plastic frame 302. The reflective sheet 304, the LED strip 200, the light guide plate 301, the middle diffusion sheet 305, and the upper diffusion sheet 306 are integrally assembled as a backlight module.

It should be noted that the manufacturing process of the LED light bar of the present invention is also suitable for the manufacture of a single LED chip. The LED light bar manufactured by the invention is not only suitable for mobile phones, but also suitable for modules such as car navigation and IPad.

The invention has the following advantages:

(1) The LED particles of the present invention are top-emitting, have small pitches, have no cups, reduce the auxiliary cup frame, effectively utilize the space, increase the number of products, increase the light-emitting area, and use the entire light bar as a light-emitting surface. Thereby, the brightness of the whole screen of the backlight product is improved by about 3-4 times that of the conventional backlight, and the screen of the mobile phone user can be solved. Dark and other issues;

The above description has fully disclosed the specific embodiments of the present invention. It should be noted that any changes to the specific embodiments of the invention will be apparent to those skilled in the art without departing from the scope of the appended claims. Accordingly, the scope of the claims of the invention is not limited to the foregoing specific embodiments.

Claims

An LED lamp, characterized in that it comprises:

a substrate comprising a conductive layer;

An LED chip fixed on the substrate, wherein an electrode is connected to an electrode on the conductive layer through a conductive line, a bottom surface of the LED chip is in contact with the substrate, and a top surface of the LED chip opposite to the bottom surface is a light emitting surface ;

A fluorescent glue covering the LED chip and bonded to the substrate, and light emitted from a top surface of the LED chip is emitted outward through the fluorescent glue.
The LED lamp according to claim 1, wherein a plurality of LED chips are fixed on the substrate, and the LED chips are fixed on one side of the substrate and formed in one or more rows.
The LED lamp according to claim 1, wherein the fluorescent glue has an isosceles trapezoidal shape, a square shape or a semicircular shape.
The LED lamp of claim 1 wherein the width of the substrate is equal to the width of coverage of the phosphor on the substrate.
The LED lamp of claim 1 , wherein the conductive layer of the substrate further comprises an external electrode, and the external power source supplies power to the LED chip through the external electrode to cause the LED chip to emit light.
A manufacturing process of an LED lamp, characterized in that:

Providing a substrate, the substrate comprising a conductive layer;

Fixing a plurality of LED chips on one side of the substrate, the LED chips are formed in one or more rows, a bottom surface of the LED chip is in contact with the substrate, and a top surface of the LED chip opposite to the bottom surface a luminous surface;

Connecting the positive and negative electrodes of the top surface of the LED chip to the electrodes on the conductive layer through conductive wires;

The fluorescent glue is pressed onto the substrate by molding, so that the fluorescent glue covers the LED chip, and light emitted from the top surface of the LED chip is emitted outward through the fluorescent glue;

The stamped substrate is cut into a plurality of LED strips or a plurality of LED lamp particles.
The manufacturing process of the LED lamp according to claim 6, wherein the fluorescent glue has a cross section of an isosceles trapezoid, a square or a semicircle.
The manufacturing process of the LED lamp according to claim 6, wherein the width of the substrate is equal to the coverage width of the fluorescent glue on the substrate.
The LED lamp manufacturing process according to claim 6, wherein each of the LED strips comprises a plurality of individual LED particles, and the plurality of LED particles are connected in series on the conductive layer.
The manufacturing process of the LED lamp according to claim 6, characterized in that the cut LED light bar and the light guide plate are assembled into a backlight module.
A backlight module includes a reflective sheet, an LED strip, a light guide plate, and a diffuser. The LED strip is located between the reflective sheet and the light guide plate and is located at one side edge of the light guide plate. Positioned in the immediate vicinity of the light guide plate, the LED light bar includes an LED chip having a conductive layer substrate, being fixed on the substrate, and a fluorescent glue covering the LED chip and bonded to the substrate. An electrode of the LED chip is connected to an electrode on the conductive layer through a conductive line, a bottom surface of the LED chip is connected to the substrate, and a top surface of the LED chip opposite to the bottom surface is a light emitting surface, and the LED Light emitted from the top surface of the chip is emitted outward through the fluorescent glue.

The top surface of the fluorescent glue of the LED strip is next to the light guide such that the light emitting surface of the LED chip of the LED strip directly faces the light guide.
The backlight module according to claim 11, wherein the substrate comprises a metal layer and a resin layer, and the metal layer is the conductive layer.
The backlight module according to claim 11, wherein the fluorescent glue has an isosceles trapezoidal shape, a square shape or a semicircular shape.
The backlight module of claim 11, wherein the width of the LED strip is equal to the coverage width of the phosphor on the substrate.
The backlight module according to claim 11, wherein the LED strip has a thickness of 0.3-0.5 mm.
The backlight module according to claim 11, wherein the plurality of LED chips are arranged in a row on the substrate, and the fluorescent glue is separately coated on the periphery of each LED chip, or The fluorescent glue is integrally coated on the periphery of the row of LED chips.
The backlight module according to claim 11, wherein the reflection sheet, the light guide plate and the diffusion plate are flat, and they are placed in parallel with each other.

The backlight module includes an outer frame, and the reflective sheet, the LED light strip, the light guide plate and the diffusion plate are disposed in the outer frame.