Large-light-emitting-angle area light source and manufacturing method thereof

Abstract

The invention provides a large-light-emitting-angle area light source. The large-light-emitting-angle area light source comprises a substrate, a box dam, an LED chip, a gold wire, an electrode bonding pad and fluorescent glue. A plurality of copper foil circuits are laid on the substrate, and the electrode bonding pad is arranged at the edge of the substrate and connected with the copper foil circuits; a box dam made of transparent materials is arranged on the substrate, the surface, located on the inner side of the box dam, of the substrate protrudes to form a plurality of long-strip-shaped trapezoid bosses, the trapezoid bosses are arranged in an arrayed mode, each trapezoid boss is provided with a plurality of sets of LED chips, the LED chips in each set are connected through gold threads, and the LED chips are connected through the gold threads. The two LED chips located on the outermost side are connected with the substrate through gold wires, and a plurality of LED chip sets are formed. The fluorescent glue is filled in the box dam and covers the LED chips and the gold threads, the LED chip sets are arranged on the top and the two sides of the trapezoid boss, the light emitting angle of the light source can be increased, the box dam is made of transparent materials, light rays are prevented from being shielded by the box dam, and the light emitting angle of the area light source is effectively increased.

Description

Technical Field

[0001] The present invention relates to a surface light source, in particular to a surface light source with a large light output angle. The present invention also relates to a method for making a surface light source, in particular to a method for making a surface light source with a large light output angle, and belongs to the technical field of integrated light sources. Background Art

[0002] At present, the light source structure formed by packaging LED chips with reflector structures has a light output angle of only about 120°, which is limited in the application of surface light sources in the backlight display and lighting industries. There are currently two main types of traditional direct-type surface light modules:

[0003] (1) Figure 1 As shown, a light source array composed of conventional LED chips is used, and a diffusion plate is arranged at a certain distance above the LED light source array, and the diffusion plate is used to convert the point light source into a surface light source;

[0004] (2) Figure 2 As shown, a light source array composed of conventional LED chips is used, and a lens is installed closely on each LED chip, so that the light emitted by the LED lamp beads passes through the lens, and then the light is transmitted through the air layer between the lens and the diffuser plate, and after a certain degree of light intensity superposition, it is irradiated onto the diffuser plate, thereby turning the point light source into a surface light source;

[0005] Both of the above methods have certain disadvantages or limitations:

[0006] For the first method: the maximum light output angle of conventional LED light sources is about 120°. The LED light source and the diffuser must be spaced a large distance apart to achieve a more uniform light mixing effect. The entire surface light output module is usually very thick and can generally only be used in the lighting industry, such as panel lights, and its application is very limited.

[0007] For the second method: the light output angle after superimposing a lens on a conventional LED light source can reach 135°. Although it increases the light-emitting angle and greatly reduces the light output from the top surface, it can achieve a more uniform mixed light effect within a relatively shorter distance. Due to the need to use a secondary optical lens, a certain distance must be set between the diffuser plate and the secondary optical lens. Although the thickness is reduced compared to the first method, the surface light output module cannot achieve an ultra-thin effect.

[0008] The surface light source using the first and second methods is not only easy to form dark areas and poor light mixing uniformity due to the limitation of the light output angle of the LED chip, but the entire direct-down surface light output module is also relatively thick. If the thickness of the entire surface light output module is to be reduced, it can only be achieved by reducing the distance between adjacent LED chips, but the number of LED chips required will be greatly increased, and the cost will be greatly increased. It is urgent to develop a surface light source with a large light output angle to solve the above problems. Summary of the invention

[0009] In view of the above problems, the present invention discloses a large light emitting angle surface light source and a manufacturing method thereof, wherein a LED chip is arranged on a boss and a dam is made of transparent material to achieve large-angle light emitting.

[0010] The specific technical solutions are as follows:

[0011] A large light output angle surface light source comprises a substrate, a dam, an LED chip, a gold wire, an electrode pad, and a fluorescent glue; a plurality of copper foil circuits are laid on the substrate, and the electrode pad is arranged at the edge of the substrate and connected to the copper foil circuit; a dam made of a transparent material is arranged on the substrate, and a surface protrusion of the substrate located inside the dam forms a plurality of long trapezoidal bosses, and the plurality of trapezoidal bosses are arranged in an array, and a plurality of groups of the LED chips are arranged on the top and both sides of each of the trapezoidal bosses, and the LED chips in each group are respectively arranged on the top and both sides of the trapezoidal bosses and are connected in series through gold wires, and the two LED chips located on the outermost sides are respectively connected to the substrate through gold wires to form a plurality of LED chip groups; the fluorescent glue is filled in the dam and covers the LED chips and the gold wires.

[0012] Preferably, the substrate is a square aluminum substrate, a dam of the annular structure is arranged at the center of the substrate, and a plurality of trapezoidal bosses located in the annular dam are parallel to each other.

[0013] Preferably, the surface of the substrate located within the dam is plated with mirror aluminum.

[0014] Preferably, an electrode pad for connecting a positive power line and a negative power line is respectively arranged at opposite end corners of the substrate, and the electrode pad is connected to the copper foil circuit.

[0015] Preferably, the substrate is covered with white oil on the copper foil circuit except the electrode pads.

[0016] Preferably, the number of LED chips in each group is three, and the three LED chips are respectively arranged on the top and two sides of the trapezoidal boss, and the two LED chips located on the two sides are symmetrically arranged.

[0017] Preferably, the LED chip is fixed on the trapezoidal boss by a die-bonding adhesive.

[0018] A method for manufacturing a surface light source with a large light output angle comprises the following steps:

[0019] Step 1: Make a square aluminum substrate with a side length of A. Punch out a number of parallel and equally spaced trapezoidal bosses in a circle with a radius of R and a center of the aluminum substrate;

[0020] Step 2: Laying a BT insulation layer on the aluminum substrate;

[0021] Step 3: Electroplating mirror aluminum in the middle area of ​​the BT insulation layer, which is a circle with a radius of R and a center of the aluminum substrate;

[0022] Step 4: Lay copper foil circuits on the BT insulation layer and cover the areas except the two electrode pads with white oil;

[0023] Step 5: Fix the LED chips on the trapezoidal bosses at equal intervals through the crystal-bonding adhesive, and put the substrate with the LED chips into a constant temperature box to cure the crystal-bonding adhesive;

[0024] Step 6: Use gold wire to connect every M LED chips into a string to form N LED chip groups, the positive electrode of the first LED chip in the LED chip group is connected to the positive copper foil line through the gold wire, and the negative electrode of the last LED chip in the LED chip group is connected to the negative copper foil line through the gold wire;

[0025] Step 7: With the center of the mirror aluminum as the center of the circle, use dam glue to surround all LED chips in a ring-shaped dam; put the substrate with the dam into a constant temperature box to cure the dam;

[0026] Step 8: Fill the dam with fluorescent glue and test it with a photoelectric parameter tester. After passing the test, put it into a constant temperature box to cure the fluorescent glue in sections. After curing, a finished light source is obtained.

[0027] Step 9: Use a photoelectric parameter tester to test the cured light source and retain the finished light source that has passed the test.

[0028] Furthermore, in step five, the curing temperature of the thermostat is 150° C., and the curing time is 120 minutes.

[0029] Furthermore, in step seven, the curing temperature of the thermostat is 130° C., and the curing time is 30 minutes.

[0030] Furthermore, in step eight, the curing of the fluorescent glue is divided into three stages. The first stage has a curing temperature of 100°C and a curing time of 30 minutes; the second stage has a curing temperature of 130°C and a curing time of 60 minutes; and the third stage has a curing temperature of 150°C and a curing time of 180 minutes.

[0031] Beneficial technical effects of the present invention:

[0032] (1) The present application arranges the LED chip group at the top and both sides of the trapezoidal boss to increase the light output angle of the light source, so that the maximum light output angle can reach 180°.

[0033] (2) Since the light output angle of the light source itself is large enough, there is no need to use a secondary optical lens to expand the light output angle, and an ultra-thin surface light output module can be easily realized.

[0034] (3) At the same time, the dam made of transparent material can avoid blocking the light and effectively increase the light output angle of the surface light source. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the structure of a traditional direct-down surface-emitting light module using method one.

[0036] Figure 2 This is a schematic diagram of the structure of a traditional direct-down surface-emitting light module that adopts method 2.

[0037] Figure 3 It is a schematic structural diagram of a surface light source with a large light output angle according to the present invention.

[0038] Figure 4 It is a cross-sectional view of a surface light source with a large light output angle according to the present invention.

[0039] Explanation of the reference numerals: 1-substrate, 2-dam, 3-LED chip, 4-fluorescent glue, 5-electrode pad, 6-gold wire, 7-trapezoidal boss. DETAILED DESCRIPTION

[0040] In order to make the technical solution of the present invention clearer, the present invention is further described below in conjunction with the accompanying drawings. Any equivalent replacement of the technical features of the technical solution of the present invention and any solution derived from conventional reasoning shall fall within the protection scope of the present invention. The fixed connection and fixed setting mentioned in the present invention are all common connection methods in the mechanical field, including welding, bolt and nut connection, and screw connection.

[0041] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0042] like Figure 3-4As shown, this embodiment provides a surface light source with a large light output angle, including a substrate 1, a dam 2, an LED chip 3, a gold wire 6, an electrode pad 5, and a fluorescent glue 4; the substrate 1 is a square aluminum substrate 1, and a plurality of copper foil circuits are laid on the substrate 1, and the electrode pad 5 is arranged at the edge of the substrate 1 and connected to the copper foil circuit. A dam 2 of an annular structure is arranged at the center of the substrate 1. The dam 2 is made of a transparent material. The surface of the substrate 1 located inside the dam 2 is raised to form a plurality of long trapezoidal bosses 7. The plurality of trapezoidal bosses 7 are arranged in an array and are parallel to each other. Both ends of each trapezoidal boss 7 extend to the dam 2. A plurality of groups of LED chips 3 are arranged on each trapezoidal boss 7. The number of LED chips 3 in each group is three. The three LED chips 3 are arranged on the top and both sides of the trapezoidal boss 7 to increase the light output angle of the light source. The adjacent two LED chips 3 in each group are connected by a gold wire 6. The two LED chips 3 located on the outermost side are connected to the substrate 1 by the gold wire 6, and a plurality of LED chip 3 groups are formed. The dam 2 is filled with fluorescent glue 4 and covers the LED chips 3 and the gold wire 6. The dam 2 made of a transparent material can avoid the dam 2 from blocking the light and increase the light output angle of the surface light source. There is no need to use a secondary optical lens to expand the light output angle, and an ultra-thin surface light output module is realized.

[0043] In this embodiment, the surface of the substrate 1 located within the dam 2 is plated with mirror aluminum with a reflectivity of 98%, and the mirror aluminum covers the trapezoidal boss 7, so that the light emitted by the LED chip 3 is effectively reflected, thereby increasing the light output efficiency.

[0044] In this embodiment, an electrode pad 5 for connecting a positive power line and a negative power line is respectively provided at opposite ends of the substrate 1 , and the electrode pad 5 is connected to the copper foil circuit.

[0045] In this embodiment, the copper foil circuit of the substrate 1 except the electrode pad 5 is covered with white oil to form a protective film to prevent the welding surface from being oxidized and improve the welding effect.

[0046] In this embodiment, the cross-section of the trapezoidal boss 7 is an isosceles trapezoidal structure, so that the two LED chips 3 located on both sides of the trapezoidal boss 7 are symmetrically arranged, and the angles between the two inclined LED chips 3 and the substrate 1 are the same, so that the maximum light output angle can reach 180°.

[0047] In this embodiment, the LED chip 3 is fixed on the trapezoidal boss 7 by a die-bonding adhesive.

[0048] This embodiment also provides a method for manufacturing a large light emitting angle surface light source, which specifically includes the following steps:

[0049] Step 1: A square aluminum substrate is manufactured, the side length of which is A. A circle with a radius of R and the center of the aluminum substrate is used as the center of the circle, and a plurality of parallel and equally spaced trapezoidal bosses 7 are punched out.

[0050] Step 2: Lay a BT insulation layer on the aluminum substrate 1.

[0051] Step 3: Electroplate mirror aluminum in the middle area of ​​the BT insulation layer. This area is a circle with a radius of R and the center of the aluminum substrate as the center.

[0052] Step 4: Lay a copper foil circuit on the BT insulation layer and cover the area except the two electrode pads 5 with white oil;

[0053] Step 5: Fix the LED chips 3 on the trapezoidal bosses 7 at equal intervals through the bonding adhesive, and put the substrate 1 with the LED chips 3 into a constant temperature box to cure the bonding adhesive; the curing temperature is 150° C. and the curing time is 120 minutes.

[0054] Step six: Use gold wire 6 to connect every three LED chips 3 on the trapezoidal boss 7 into a string to form N LED chip 3 groups. The positive electrode of the first LED chip 3 in the LED chip 3 group is connected to the positive copper foil circuit through the gold wire 6, and the negative electrode of the last LED chip 3 in the LED chip 3 group is connected to the negative copper foil circuit through the gold wire 6.

[0055] Step 7: With the center of the mirror aluminum as the center of the circle, use the dam 2 glue to surround all the LED chips 3 in a ring-shaped dam 2; put the substrate 1 with the dam 2 into a constant temperature box to cure the dam 2 at a curing temperature of 130°C for 30 minutes.

[0056] Step 8: Fill the dam 2 with fluorescent glue 4 and test it with a photoelectric parameter tester. After passing the test, put it into a constant temperature box to cure the fluorescent glue 4. After curing, a finished light source is obtained. The fluorescent glue 4 is cured in stages. The first stage is cured at a temperature of 100°C and a curing time of 30 minutes; the second stage is cured at a temperature of 130°C and a curing time of 60 minutes; the third stage is cured at a temperature of 150°C and a curing time of 180 minutes.

[0057] Step 9: Use a photoelectric parameter tester to test the cured light source and retain the finished light source that has passed the test.

[0058] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A large light output angle surface light source, comprising a substrate (1), a dam (2), an LED chip (3), a gold wire (6), an electrode pad (5), and a fluorescent glue (4); a plurality of copper foil circuits are laid on the substrate (1), and the electrode pad (5) is arranged at the edge of the substrate (1) and connected to the copper foil circuit; characterized in that: A dam (2) made of a transparent material is arranged on the substrate (1); the surface of the substrate (1) located inside the dam (2) is raised to form a plurality of long trapezoidal bosses (7); the plurality of trapezoidal bosses are arranged in an array; a plurality of groups of LED chips (3) are arranged on each of the trapezoidal bosses; the LED chips (3) in each group are respectively arranged on the top and both sides of the trapezoidal bosses and are connected in series via gold wires; the two LED chips (3) located on the outermost sides are respectively connected to the substrate (1) via gold wires, and form a plurality of LED chip (3) groups; the dam (2) is filled with the fluorescent glue and covers the LED chips (3) and the gold wires.

2. A surface light source with a large light output angle as claimed in claim 1, characterized in that: The substrate (1) is a square aluminum substrate (1), and the annular dam (2) is arranged at the center of the substrate (1), and a plurality of trapezoidal bosses (7) located inside the annular dam (2) are parallel to each other.

3. A surface light source with a large light output angle as claimed in claim 2, characterized in that: The surface of the substrate (1) located inside the dam (2) is plated with mirror aluminum.

4. A surface light source with a large light output angle as claimed in claim 1, characterized in that: An electrode pad for connecting a positive power line and a negative power line is respectively arranged at opposite end corners of the substrate (1), and the electrode pad is connected to the copper foil circuit.

5. A surface light source with a large light output angle as claimed in claim 4, characterized in that: The substrate (1) is covered with white oil on the copper foil circuit except the electrode pad.

6. A surface light source with a large light output angle as claimed in claim 1, characterized in that: The number of LED chips (3) in each group is three, and the three LED chips (3) are respectively arranged on the top and two sides of the trapezoidal boss, and the two LED chips (3) located on the two sides are symmetrically arranged.

7. A large light-emitting angle surface light source as claimed in claim 6, characterized in that: The LED chip (3) is fixed on the trapezoidal boss (7) by means of a crystal-fixing adhesive.

8. A method for manufacturing a surface light source with a large light output angle as claimed in any one of claims 1 to 7, characterized in that: The specific steps include: Step 1: Prepare a square aluminum substrate with a side length of A, and punch out a number of parallel and equally spaced trapezoidal bosses (7) in a circle with a radius of R and a center of the aluminum substrate as the center; Step 2: Laying a BT insulation layer on the aluminum substrate; Step 3: Electroplating mirror aluminum in the middle area of ​​the BT insulation layer, which is a circle with a radius of R and a center of the aluminum substrate; Step 4: Lay copper foil circuits on the BT insulation layer and cover the areas except the two electrode pads with white oil; Step 5: Fix the LED chips (3) on the trapezoidal bosses at equal intervals by using a bonding adhesive, and place the substrate (1) with the LED chips (3) into a constant temperature box to cure the bonding adhesive; Step 6: Using gold wire, every M LED chips (3) are connected in a string to form N LED chip (3) groups, the positive electrode of the first LED chip (3) in the LED chip (3) group is connected to the positive electrode copper foil circuit through the gold wire, and the negative electrode of the last LED chip (3) in the LED chip (3) group is connected to the negative electrode copper foil circuit through the gold wire; Step 7: With the center of the mirror aluminum as the center of the circle, all the LED chips (3) are enclosed in a ring-shaped dam (2) using dam (2) glue; the substrate (1) with the dam (2) is placed in a constant temperature box to cure the dam (2); Step 8: Fill the dam (2) with fluorescent glue and test it with a photoelectric parameter tester. After passing the test, put it into a constant temperature box to cure the fluorescent glue in sections, and obtain a finished light source after curing; Step 9: Use a photoelectric parameter tester to test the cured light source and retain the finished light source that has passed the test.

9. The method according to claim 8, characterized in that In the step 5, the curing temperature of the thermostat is 150° C. and the curing time is 120 minutes; in the step 7, the curing temperature of the thermostat is 130° C. and the curing time is 30 minutes.

10. The method according to claim 8, characterized in that In step eight, the curing of the fluorescent glue (4) is divided into three stages. The first stage has a curing temperature of 100° C. and a curing time of 30 minutes; the second stage has a curing temperature of 130° C. and a curing time of 60 minutes; and the third stage has a curing temperature of 150° C. and a curing time of 180 minutes.

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