How is liquid crystal made?
Author:Zhou Zi Time:2021-08-06 14:37 Browse(564)
Like semiconductors, liquid crystal is a high-tech industry with high requirements for production process and technology, which is also an important reason for the monopoly of this kind of production technology in a few countries. In fact, the research of TFT-LCD originated in Europe and America, and its industrialization was completed by Japan. Therefore, the earliest theoretical research and basic patents are mainly concentrated in Europe and the United States, while the technology of products and processes is mainly in the hands of Japan and South Korea. Most of the technology of Taiwan's manufacturers mainly comes from the authorization of other manufacturers, and the technology patents are few. Most of them are OEM manufacturing of LCD panel, but Taiwan's LCD panel industrialization is the world's leading.
Like semiconductors, liquid crystal is a high-tech industry with high requirements for production process and technology, This is also an important reason for the monopoly of this kind of production technology in a few countries.
in fact, the research of TFT-LCD originated in Europe and the United States.
the industrialization was completed by Japan.

How is liquid crystal made?

therefore, the earliest theoretical research and basic patents were mainly concentrated in Europe and the United States.
the technology of products and processes was mainly in the hands of Japan and South Korea.
the technology of most manufacturers in Taiwan mainly came from other manufacturers
there are few technical patents, most of which are OEM manufacturing of LCD panel, However, the industrialization of liquid crystal panel in Taiwan is leading in the world.
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the main manufacturing process of liquid crystal panel:
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1. Array process:
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mainly manufacturing TFT substrate and color filter (CF substrate).
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process: glass cleaning --- film forming --- cleaning --- photoresist coating --- exposure --- etching --- photoresist stripping --- cleaning --- testing.
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2 Sheet forming process:
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the TFT glass substrate made in the previous process array and CF glass substrate are treated by alignment The process is as follows: TFT & CF glass substrate cleaning, alignment film forming, cleaning, frame glue spreading, liquid crystal pouring, alignment pressing, splitting cutting, polarizing plate sticking, lighting inspection.
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3. Module (module assembly) process:
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connect the panel processed by cell process with tab, PCB, backlight module, PCB, backlight module The outer frame and other peripheral parts are assembled
process: ACF chip ---> IC joint ---> plastic coating ---> backlight frame assembly ---> environment test ---> inspection test.
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after watching flash, maybe you don't understand the basic structure of liquid crystal.
then take a closer look at the figure below, In the following, I will explain the basic principle of liquid crystal.
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the composition and structure of liquid crystal panel.
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from the above figure, we can see that the separated parts of liquid crystal panel are more like a multilayer sandwich.
before we understand the function of these parts, we first understand the basic imaging principle of liquid crystal.
in fact, the liquid crystal material itself does not emit light.
from the above figure, we can see that The liquid crystal sandwiched between the color filter (CF substrate) and the TFT glass mainly acts as a camera shutter, The deflection angle of the liquid crystal molecules is changed by the change of the applied voltage, so as to control the light transmission from the backlight.
then the color filter is used to form a picture with color and light and dark layers.
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basic structure of the liquid crystal panel:
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front frame: the front frame is a metal or plastic outer frame.
it is used to protect the edge of the LCD and prevent the impact of electrostatic discharge
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horizontal polarizer: polarizer is a kind of optical plate which only allows light in a certain polarization direction to pass through.
it can convert natural light into linear polarized light.
its mechanism is to pass the right angle incident light through the horizontal polarizer and make the light in the horizontal direction pass through.
another part of the light in the vertical direction is absorbed, Or use reflection and scattering to shield it.
in the process of making LCD,
one piece must be used at the top and one piece at the bottom,Color filter: color LCD needs color filter.
signal processing through control IC, The color filter is made on the glass substrate.
the red, green and blue organic photoresist materials are made in each pixel.
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liquid crystal: liquid crystal is a special material.
in addition to the variable refractive properties of general solid crystal, the liquid crystal has the same properties as the liquid crystal, At the same time, it has the fluidity of liquid, and the arrangement direction of liquid molecules can be controlled by electric or magnetic fields.
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TFT glass: the TFT glass panel is composed of millions of TFT dice and ITO (transparent conductive metal) which control the liquid crystal region arranged in a matrix.
therefore, it is called array, The first part of flash describes the manufacturing process of this part.
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vertical polarizer: polarizer is a kind of optical plate that only allows light in a certain direction to pass through.
optical element that can convert natural light into linear polarized light.
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driving IC and printed circuit board: the main function of this part is to output the required voltage to pixels.
to control liquid crystal molecules
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Diffuser: the function of the diffuser is to diffuse the light source emitted from the backlight module and make its brightness uniform.
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Diffuser: similar to the function of the diffuser.
provides a uniform area light source for the LCD.

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plastic frame: it is mainly used to fix the whole backlight module.
improper placement, collision, dirt and other damage and influence on the function of backlight module.
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backlight: because the liquid crystal material itself does not emit light.
it must rely on additional light source to achieve the display function. The light source is generally located behind the LCD panel, So it's called backlight.
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backplane: a device that fixes backlight.
LCD, circuit, etc. on the frame structure, It is used for the final assembly of LCD.
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main control board: the driving control circuit board of LCD.
converts the image input signal into the display signal of LCD.
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backlight module lighting device: the backlight module lighting device converts the DC voltage signal with power supply into high frequency and high voltage pulse AC.
and continuously lights up the cold cathode lamp tube in the backlight module.
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the backlight module lighting device is used for the final assembly of LCD In general, the manufacturing of LCD panel is a very complex process.
the cost of production line is even higher.
the high requirements for technology and production process result in a special relationship between downstream display consumer goods and upstream panel manufacturers.
in the upstream resources.
Japan, South Korea and Taiwan occupy the vast majority of the current LCD panel market, However, the local LCD panel enterprises in mainland China have certain objective resistance in the introduction of technology and the improvement of production process, and the ability of independent research and development is not strong, which is an important reason why the local LCD panel enterprises in mainland China are out of business www.niexvhong.cn.
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