CN111790957A

CN111790957A - Sawtooth process for solving side yellowing of backlight LED

Info

Publication number: CN111790957A
Application number: CN202010554524.0A
Authority: CN
Inventors: 柯清维; 周彬; 柯钊
Original assignee: Shenzhen Longli Technology Co Ltd
Current assignee: Shenzhen Longli Technology Co Ltd
Priority date: 2020-06-17
Filing date: 2020-06-17
Publication date: 2020-10-20
Anticipated expiration: 2040-06-17
Also published as: CN111790957B

Abstract

The invention relates to a sawtooth process for solving the problem of yellowing of a backlight LED side, which comprises the following steps of S1: processing a mould, namely processing the mould according to the requirement of a drawing; step S2: processing a sawtooth surface, namely processing the sawtooth surface on a die in a slow wire feeding mode to form the sawtooth surface, and roughening the sawtooth surface; step S3: and (3) injection molding, namely installing the mold on an injection molding machine for injection molding, and then cooling and molding to obtain the light guide plate with the roughened sawtooth surface. According to the invention, the sawtooth surface is processed in a slow wire feeding mode, the sawtooth surface is corroded by pulse spark discharge, the surface of the sawtooth surface is roughened by the discharge processing while the sawtooth is cut, the surface roughness of the sawtooth surface is irregular, the dispersion of a prism is damaged, and the light diffuse reflection is increased, so that the light is mixed more sufficiently after entering the light guide plate, the light emitted by the LED side is more uniform, and further the yellowing phenomenon is effectively avoided.

Description

Sawtooth process for solving side yellowing of backlight LED

Technical Field

The invention relates to the technical field of light guide plates, in particular to a sawtooth process for solving the problem of yellowing of a backlight LED side.

Background

The backlight module is a provider of a light source of a Liquid Crystal Display (LCD), the LCD does not emit light, and the appearance of the light source of the backlight module determines the visual sense of the LCD. The backlight module is internally provided with a light guide plate which is a transmission medium of a backlight module light source and has the function of converting a point light source into a surface light source.

The smart phone adopts the backlight module of side income formula, and the LED light source of side income formula backlight module is located one side of light guide plate, and the light that LED sent propagates in the light guide plate board, and propagation path can be through the change and the interference of different faces, and it has three faces to influence light guide plate optical property (as figure 1): the light incident surface 200, the light emergent surface 100 and the dot surface 300 are opposite to each other, and the structure of the light incident surface 200 directly affects the angle and intensity of light rays emitted by the LED entering the light guide plate, wherein the light rays emitted by the LED enter the light guide plate and the dot surface 300 is opposite to the light emergent surface 100.

At present, the light incident surface of the light guide plate is generally provided with a sawtooth microstructure, the sawtooth microstructure is arc-shaped, pointed, trapezoidal and the like, the sawtooth microstructure of the light guide plate is obtained by transferring by a mould, and the roughness RA of the surface of the sawtooth surface is about 0.05um because the processing technology of the sawtooth surface on the mould is mainly grinding processing. After grinding, a rough surface of the prism is formed on the surface of the sawtooth surface, the prisms are regularly arranged along the processing direction of the grinding wheel, light rays emitted from the LED side are remixed under the action of the sawtooth surface prism, and the more regular the prism is, the worse the prism is. And the mobile phone frame is narrower and narrower, the light mixing area is also narrower and narrower, the light emitted by the LED passes through the surface of a regular prism, the dispersion phenomenon occurs, the wavelength of yellow light is right in the middle, the domain width is large, the yellow light is easy to be sensed by naked eyes, and the phenomenon that the visual effect is yellow is caused.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a sawtooth process for solving the problem that the side of a backlight LED is yellow, which can avoid the phenomenon that the light emitted by the LED passes through the surface of a regular prism to generate dispersion, the wavelength of the yellow light is just in the middle, the domain width is large, and the phenomenon that the visual effect is yellow easily sensed by naked eyes is avoided.

The above object of the present invention is achieved by the following technical solutions:

a sawtooth process for solving yellowing of a backlight LED side comprises the following steps:

step S1: processing a mould, namely processing the mould according to the requirement of a drawing;

step S2: processing a sawtooth surface, namely processing the sawtooth surface on a die in a slow wire feeding mode to form the sawtooth surface, and roughening the sawtooth surface;

step S3: and (3) injection molding, namely installing the mold on an injection molding machine for injection molding, and then cooling and molding to obtain the light guide plate with the roughened sawtooth surface.

Through adopting above-mentioned technical scheme, utilize and walk a mode processing sawtooth surface slowly, pulse spark discharge can corrode and remove the sawtooth surface, utilizes discharge machining to carry out the alligatoring to the surface of sawtooth surface when cutting the sawtooth, lets the surface roughness of sawtooth surface not have the law, destroys the chromatic dispersion of prism, increases light diffuse reflection to it is more abundant to make light mix the light behind the light entering light guide plate, and the light that lets the LED side send is more even, and then effectively avoids appearing the phenomenon of yellowish.

The present invention in a preferred example may be further configured to: the surface roughness RA of the sawtooth surface is 10um-20 um.

By adopting the technical scheme, the surface roughness RA of the sawtooth surface reaches about 15um, the surface diffuse reflection ratio of the sawtooth surface reaches the peak value, the diffuse reflection effect is good, the roughness is increased again, and the diffuse reflection ratio is basically unchanged.

The present invention in a preferred example may be further configured to: when the wire is slowly cut, the current of the discharge is between 1A and 3A, and the diameter of the wire cut processing wire is 0.015 mm.

Through adopting above-mentioned technical scheme, the diameter can process 0.02 mm's roughness for 0.015 mm's processing line, through setting up like this, the surface roughness RA of the sawtooth surface that the line was cut out just can reach 10um-20 um.

The present invention in a preferred example may be further configured to: the processing line of the wire cutting is a copper wire.

By adopting the technical scheme, the copper wire has good conductivity and good discharge stability, and the processing speed and quality are convenient to control.

The present invention in a preferred example may be further configured to: the line cutting mode is cutting one and repairing three.

By adopting the technical scheme, the machining precision is convenient to control and improve by cutting one to repair three.

The present invention in a preferred example may be further configured to: the first cutting and the third cutting are that the first cutting leaves a margin of 0.03mm for the saw teeth, and the margin of 0.01mm is removed every time in the last three times of trimming.

By adopting the technical scheme, the saw teeth are cut out by the first cutting to leave 0.03mm of allowance, and the 0.01mm of allowance is removed every time in three times of later trimming, so that the saw tooth surface with the required size is obtained, and the processing precision is high.

The present invention in a preferred example may be further configured to: in step S3, before the mold is mounted on the injection molding machine, the mold is detected by the 3D detector, and the mold is mounted until the actual value of the mold reaches the standard.

By adopting the technical scheme, the mould is filled only when the mould reaches the standard, and the finished product yield of the light guide plate is improved.

In summary, the invention includes at least one of the following beneficial technical effects:

1. utilize and walk a mode processing sawtooth surface slowly, pulse spark discharge can corrode the sawtooth surface, utilizes discharge machining to carry out the alligatoring to the surface of sawtooth surface when cutting the sawtooth, lets the surface roughness of sawtooth surface not have the law, destroys the chromatic dispersion of prism, increases light diffuse reflection to it is more abundant to make light mix the light behind the entering light guide plate, and the light that lets the LED side send is more even, and then effectively avoids appearing the phenomenon of yellowish.

2. The surface roughness RA of the sawtooth surface is 10-20um, the surface diffuse reflection ratio of the sawtooth surface reaches the peak value, and the diffuse reflection effect is good.

3. And the machining precision is convenient to control and improve by a mode of cutting one and repairing three.

Drawings

FIG. 1 is a schematic view of a light guide plate according to the prior art;

FIG. 2 is a schematic flow diagram of a sawtooth process for addressing backlight LED side yellowing;

FIG. 3 is a schematic view of a serrated insert;

fig. 4 is a schematic structural view of an injection mold for a light guide plate.

In the figure, 100, the light-emitting surface; 200. a light incident surface; 300. a mesh point surface;

1. a mold; 2. a sawtooth insert; 21. splicing blocks A; 22. splicing block B; 3. a serrated surface.

Detailed Description

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

Referring to fig. 2, the sawtooth process for solving the problem of yellowing of the backlight LED side disclosed by the invention comprises the following steps:

step S1: and (5) processing the die 1, namely processing the die 1 according to the requirement of a drawing. The die 1 comprises a sawtooth insert 2, the sawtooth insert 2 is machined into a shape in a slow wire walking mode, referring to fig. 3 and 4, the sawtooth insert 2 comprises a segment A21 and a segment B22, a 0.1mm allowance is reserved in the length, width and height directions of the segment B22, then the allowance on the surface of the segment B22 is ground off through a grinding machine to obtain the size required by a drawing, and the segment A21 directly cuts the size shape. By cutting out panel a21, space is left for the serrated face 3 to be machined.

Step S2: processing a sawtooth surface 3 on the segment B22 in a slow wire moving mode; the split A21 is fixed on a slow-speed wire machine, the leveller has well calibrated flatness, and the precision of the wire cutting machine is required to be 0.001mm level, so that the precision of the equipment can ensure that the processed sawteeth have good consistency with the plane.

After the flatness is corrected, the discharge machining is started, the discharge current is 1A-3A, a wire-cut machining wire is a copper wire with the diameter of 0.015mm, the copper wire with the diameter of 0.015mm can be machined to have the roughness of 0.02mm, the thickness of a plane cut by the wire-cut machining wire can reach Ra10-20um, the surface roughness RA of the R sawtooth surface 3 is 10um-20um, the surface diffuse reflectance of the sawtooth surface 3 reaches the peak value, the diffuse reflectance effect is good, the roughness is increased, and the diffuse reflectance is basically unchanged.

The wire cutting mode is cutting one and repairing three, wherein the cutting one and repairing three is that the first cutting leaves a margin of 0.03mm for the sawteeth, and the margin of 0.01mm is removed every time in three times of subsequent trimming, so that the lines on the surfaces of the sawteeth are uniform and consistent after cutting.

Step S3: injection molding; after the coarsening of the serrated surface 3 is completed, the mold 1 is firstly detected by a 3D detector, and the mold 1 is filled when the size of the mold 1 and the roughness of the serrated surface 3 reach the standard. And (3) assembling the sawtooth insert 2 according to an assembly drawing of the mould 1, referring to a drawing 4, installing the assembled mould 1 on an injection molding machine according to the operation requirement, and then performing injection molding according to the machine-adjusting operation program of the injection molding machine. After cooling and forming, the roughened sawtooth state of the sawtooth insert 2 is transferred to the light incident position of the light guide plate, and then the light guide plate capable of solving the problem of yellowing of the backlight LED side is obtained.

The implementation principle of the embodiment is as follows: utilize and walk a mode processing sawtooth surface 3 slowly, pulse spark discharge can corrode sawtooth surface 3, utilizes discharge machining to carry out the alligatoring to sawtooth surface 3 when cutting the sawtooth, lets sawtooth surface 3's surface roughness not have the law, destroys the chromatic dispersion of prism, increases light diffuse reflection to it is more abundant to make light mix the light behind the light entering light guide plate, and the light that lets the LED side send is more even, and then effectively avoids appearing the phenomenon of yellowish.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. A sawtooth process for solving the problem of yellowing of a backlight LED side is characterized by comprising the following steps:

step S1: processing the die (1), namely processing the die (1) according to the drawing requirement;

step S2: processing the serrated surface (3), processing the serrated surface (3) on the die (1) in a slow wire moving mode, and roughening the serrated surface (3);

step S3: and (3) injection molding, namely installing the mold (1) on an injection molding machine for injection molding, and then cooling and molding to obtain the light guide plate with the roughened sawtooth surface (3).

2. A saw-tooth process for solving the problem of yellowing on the side of a backlight LED according to claim 1, wherein the surface roughness RA of the saw-tooth surface (3) is 10um-20 um.

3. The sawtooth process for solving the problem of the side yellowing of the backlight LED as claimed in claim 2, wherein the current discharged during slow wire cutting is 1A-3A, and the diameter of a wire cut processing wire is 0.015 mm.

4. The sawtooth process for solving the problem of yellowing on the side of the backlight LED as claimed in claim 3, wherein the processing line of the wire cutting is a copper wire.

5. The sawtooth process for solving the problem of the side yellowing of the backlight LED as claimed in claim 3, wherein the line cutting mode is cutting one and trimming three.

6. The process of claim 5, wherein the first cut and the third cut leave a margin of 0.03mm for the sawteeth, and the third cut remove a margin of 0.01mm each time.

7. The sawtooth process for solving the problem of yellowing on the side of the backlight LED according to claim 1, wherein in step S3, before the mold (1) is installed on the injection molding machine, the mold (1) is detected by a 3D detector, and the mold (1) is filled when the actual value of the mold (1) reaches the standard.