lcd panel material factory
Important technical improvements of LCD, such as LED backlighting and wide viewing Angle, are directly related to LCD. And account for an LCD display 80% of the cost of the LCD panel, enough to show that the LCD panel is the core part of the entire display, the quality of the LCD panel, can be said to directly determine the quality of an LCD display.
The production of civil LCD displays is just an assembly process. The LCD panel, the main control circuit, shell, and other parts of the main assembly, basically will not have too complex technical problems.
Does this mean that LCDS are low-tech products? In fact, it is not. The production and manufacturing process of the LCD panels is very complicated, requiring at least 300 process processes. The whole process needs to be carried out in a dust-free environment and with precise technology.
The general structure of the LCD panel is not very complex, now the structure of the LCD panel is divided into two parts: the LCD panel and the backlight system.
Due to the LCD does not shine, so you need to use another light source to illuminate, the function of the backlight system is to this, but currently used CCFL lamp or LED backlight, don’t have the characteristics of the surface light source, so you need to guide plate, spreadsheet components, such as linear or point sources of light evenly across the surface, in order to make the entire LCD panel on the differences of luminous intensity is the same, but it is very difficult, to achieve the ideal state can be to try to reduce brightness non-uniformity, the backlight system has a lot to the test of design and workmanship.
In addition, there is a driving IC and printed circuit board beside the LCD panel, which is mainly used to control the rotation of LCD molecules in the LCD panel and the transmission of display signals. The LCD plate is thin and translucent without electricity. It is roughly shaped like a sandwich, with an LCD sandwiched between a layer of TFT glass and a layer of colored filters.
LCD with light refraction properties of solid crystals, with fluid flow characteristics at the same time, under the drive of the electrode, can be arranged in a way that, in accordance with the master want to control the strength of the light through, and then on the color filter, through the red, green, blue three colors of each pixel toning, eventually get the full-screen image.
According to the functional division, the LCD panel can be divided into the LCD panel and the backlight system. However, to produce an LCD panel, it needs to go through three complicated processes, namely, the manufacturing process of the front segment Array,the manufacturing process of the middle segment Cell, and the assembly of the rear segment module. Today we will be here, for you in detail to introduce the production of the LCD panel manufacturing process.
The manufacturing process of the LCD panel Array is mainly composed of four parts: film, yellow light, etch and peel film. If we just look at it in this way, many netizens do not understand the specific meaning of these four steps and why they do so.
First of all, the motion and arrangement of LCD molecules need electrons to drive them. Therefore, on the TFT glass, the carrier of LCD, there must be conductive parts to control the motion of LCD. In this case, we use ITO (Indium Tin Oxide) to do this.ITO is transparent and also acts as a thin-film conductive crystal so that it doesn’t block the backlight.
The different arrangement of LCD molecules and the rapid motion change can ensure that each pixel displays the corresponding color accurately and the image changes accurately and quickly, which requires the precision of LCD molecule control.ITO film needs special treatment, just like printing the circuit on the PCB board, drawing the conductive circuit on the whole LCD board.
Next, a photoresist is applied to the glass on which ITO film is deposited, and a uniform photoresist layer is formed on the ITO glass. After baking for a period of time, the solvent of the photoresist was partially volatilized to increase the adhesion of the photoresist material to the ITO glass.
This completes the previous Array process. It is not difficult to see from the whole process that ITO film is deposited, photoresist coated, exposed, developed, and etched on TFT glass, and finally, ITO electrode pattern designed in the early stage is formed on TFT glass to control the movement of LCD molecules on the glass. The general steps of the whole production process are not complicated, but the technical details and precautions are very complicated, so we will not introduce them here. Interested friends can consult relevant materials by themselves.
The glass that the LCD board uses makes a craft also very exquisite. (The manufacturing process flow of the LCD display screen)At present, the world’s largest LCD panel glass, mainly by the United States Corning, Japan Asahi glass manufacturers, located in the upstream of the production of LCD panel, these manufacturers have mastered the glass production technology patents. A few months ago, the earthquake caused a corning glass furnace shutdown incident, which has caused a certain impact on the LCD panel industry, you can see its position in the industry.
As mentioned earlier, the LCD panel is structured like a sandwich, with an LCD sandwiched between the lower TFT glass and the upper color filter. The terminal Cell process in LCD panel manufacturing involves the TFT glass being glued to the top and bottom of a colored filter, but this is not a simple bonding process that requires a lot of technical detail.
As you can see from the figure above, the glass is divided into 6 pieces of the same size. In other words, the LCD made from this glass is finally cut into 6 pieces, and the size of each piece is the final size. When the glass is cast, the specifications and sizes of each glass have been designed in advance.
Then, the organic polymer directional material is coated on the surface of the glass, that is, a uniform directional layer is applied to the appropriate position of ITO glass by the method of selective coating. Meanwhile, the directional layer is cured.
Directional friction:Flannelette material is used to rub the surface of the layer in a specific direction so that the LCD molecules can be arranged along the friction direction of the aligned layer in the future to ensure the consistency of the arrangement of LCD molecules. After the alignment friction, there will be some contaminants such as flannelette thread, which need to be washed away through a special cleaning process.
After the TFT glass substrate is cleaned, a sealant coating is applied to allow the TFT glass substrate to be bonded to the color filter and to prevent LCD outflow.
Finally, the conductive adhesive is applied to the frame in the bonding direction of the glass of the color filter to ensure that external electrons can flow into the LCD layer. Then, according to the bonding mark on the TFT glass substrate and the color filter, two pieces of glass are bonded together, and the bonding material is solidified at high temperatures to make the upper and lower glasses fit statically.
Color filters are very important components of LCD panels. Manufacturers of color filters, like glass substrate manufacturers, are upstream of LCD panel manufacturers. Their oversupply or undersupply can directly affect the production schedule of LCD panels and indirectly affect the end market.
As can be seen from the above figure, each LCD panel is left with two edges after cutting. What is it used for? You can find the answer in the later module process
Finally, a polarizer is placed on both sides of each LCD substrate, with the horizontal polarizer facing outwards and the vertical polarizer facing inwards.
When making LCD panel, must up and down each use one, and presents the alternating direction, when has the electric field and does not have the electric field, causes the light to produce the phase difference and to present the light and dark state, uses in the display subtitle or the pattern.
The rear Module manufacturing process is mainly the integration of the drive IC pressing of the LCD substrate and the printed circuit board. This part can transmit the display signal received from the main control circuit to the drive IC to drive the LCD molecules to rotate and display the image. In addition, the backlight part will be integrated with the LCD substrate at this stage, and the complete LCD panel is completed.
Firstly, the heteroconductive adhesive is pressed on the two edges, which allows external electrons to enter the LCD substrate layer and acts as a bridge for electronic transmission
Next is the drive IC press. The main function of the drive IC is to output the required voltage to each pixel and control the degree of torsion of the LCD molecules. The drive IC is divided into two types. The source drive IC located in the X-axis is responsible for the input of data. It is characterized by high frequency and has an image function. The gate drive IC located in the Y-axis is responsible for the degree and speed of torsion of LCD molecules, which directly affects the response time of the LCD display. However, there are already many LCD panels that only have driving IC in the X-axis direction, perhaps because the Y-axis drive IC function has been integrated and simplified.
The press of the flexible circuit board can transmit data signals and act as the bridge between the external printed circuit and LCD. It can be bent and thus becomes a flexible or flexible circuit board
The manufacturing process of the LCD substrate still has a lot of details and matters needing attention, for example, rinse with clean, dry, dry, dry, ultrasonic cleaning, exposure, development and so on and so on, all have very strict technical details and requirements, so as to produce qualified eyes panel, interested friends can consult relevant technical information by a search engine.
LCD (LC) is a kind of LCD, which has the properties of light transmission and refraction of solid Crystal, as well as the flow property of Liquid. It is because of this property that it will be applied to the display field.
However, LCD does not emit light autonomously, so the display equipment using LCD as the display medium needs to be equipped with another backlight system.
First, a backplate is needed as the carrier of the light source. The common light source for LCD display equipment is CCFL cold cathode backlight, but it has started to switch to an LED backlight, but either one needs a backplate as the carrier.
CCFL backlight has been with LCD for a long time. Compared with LED backlight, CCFL backlight has many defects. However, it has gradually evolved to save 50% of the lamp and enhance the transmittance of the LCD panel, so as to achieve the purpose of energy-saving.
With the rapid development of LED in the field of lighting, the cost has been greatly reduced.LCD panels have also started to use LED as the backlight on a large scale. Currently, in order to control costs, an LED backlight is placed on the side rather than on the backplate, which can reduce the number of LED grains.
At the top of the diffusion plate, there will be 3~4 diffuser pieces, constantly uniform light to the whole surface, improve the uniformity of light, which is directly related to the LCD panel display effect. Professional LCD in order to better control the brightness uniformity of the screen, panel procurement, the later backlight control circuit, will make great efforts to ensure the quality of the panel.
Since the LCD substrate and the backlight system are not fixed by bonding, a metal or rubber frame is needed to be added to the outer layer to fix the LCD substrate and the backlight system.
After the period of the Module, the process is completed in LCM (LCDModule) factory, the core of this part of the basic does not involve the use of LCD manufacturing technology, mainly is some assembly work, so some machine panel factories such as chi mei, Korea department such as Samsung panel factory, all set with LCM factories in mainland China, Duan Mo group after the LCD panel assembly, so that we can convenient mainland area each big monitor procurement contract with LCD TV manufacturers, can reduce the human in the whole manufacturing and transportation costs.
However, neither Taiwan nor Korea has any intention to set up factories in mainland China for the LCD panel front and middle manufacturing process involving core technologies. Therefore, there is still a long way to go for China to have its own LCD panel industry.
Flat-panel displays are thin panels of glass or plastic used for electronically displaying text, images, or video. Liquid crystal displays (LCD), OLED (organic light emitting diode) and microLED displays are not quite the same; since LCD uses a liquid crystal that reacts to an electric current blocking light or allowing it to pass through the panel, whereas OLED/microLED displays consist of electroluminescent organic/inorganic materials that generate light when a current is passed through the material. LCD, OLED and microLED displays are driven using LTPS, IGZO, LTPO, and A-Si TFT transistor technologies as their backplane using ITO to supply current to the transistors and in turn to the liquid crystal or electroluminescent material. Segment and passive OLED and LCD displays do not use a backplane but use indium tin oxide (ITO), a transparent conductive material, to pass current to the electroluminescent material or liquid crystal. In LCDs, there is an even layer of liquid crystal throughout the panel whereas an OLED display has the electroluminescent material only where it is meant to light up. OLEDs, LCDs and microLEDs can be made flexible and transparent, but LCDs require a backlight because they cannot emit light on their own like OLEDs and microLEDs.
Liquid-crystal display (or LCD) is a thin, flat panel used for electronically displaying information such as text, images, and moving pictures. They are usually made of glass but they can also be made out of plastic. Some manufacturers make transparent LCD panels and special sequential color segment LCDs that have higher than usual refresh rates and an RGB backlight. The backlight is synchronized with the display so that the colors will show up as needed. The list of LCD manufacturers:
Organic light emitting diode (or OLED displays) is a thin, flat panel made of glass or plastic used for electronically displaying information such as text, images, and moving pictures. OLED panels can also take the shape of a light panel, where red, green and blue light emitting materials are stacked to create a white light panel. OLED displays can also be made transparent and/or flexible and these transparent panels are available on the market and are widely used in smartphones with under-display optical fingerprint sensors. LCD and OLED displays are available in different shapes, the most prominent of which is a circular display, which is used in smartwatches. The list of OLED display manufacturers:
MicroLED displays is an emerging flat-panel display technology consisting of arrays of microscopic LEDs forming the individual pixel elements. Like OLED, microLED offers infinite contrast ratio, but unlike OLED, microLED is immune to screen burn-in, and consumes less power while having higher light output, as it uses LEDs instead of organic electroluminescent materials, The list of MicroLED display manufacturers:
LCDs are made in a glass substrate. For OLED, the substrate can also be plastic. The size of the substrates are specified in generations, with each generation using a larger substrate. For example, a 4th generation substrate is larger in size than a 3rd generation substrate. A larger substrate allows for more panels to be cut from a single substrate, or for larger panels to be made, akin to increasing wafer sizes in the semiconductor industry.
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In general, there are two types of displays in the market today: active matrix liquid crystal display (AMLCD) and AMOLED. In its simplicity, the fundamental components required to make up the display are the same for AMLCD and AMOLED. There are four layers of a display device (FIGURE 1): a light source, switches that are the thin-film-transistor and where the gases are mainly used, a shutter to control the color selection, and the RGB (red, green, blue) color filter.
Technology trends TFT-LCD (thin-film-transistor liquid-crystal display) is the baseline technology. MO / White OLED (organic light emitting diode) is used for larger screens. LTPS / AMOLED is used for small / medium screens. The challenges for OLED are the effect of < 1 micron particles on yield, much higher cost compared to a-Si due to increased mask steps, and moisture impact to yield for the OLED step.
Although AMLCD displays are still dominant in the market today, AMOLED displays are growing quickly. Currently about 25% of smartphones are made with AMOLED displays and this is expected to grow to ~40% by 2021. OLED televisions are also growing rapidly, enjoying double digit growth rate year over year. Based on IHS data, the revenue for display panels with AMOLED technol- ogies is expected to have a CAGR of 18.9% in the next five years while the AMLCD display revenue will have a -2.8% CAGR for the same period with the total display panel revenue CAGR of 2.5%. With the rapid growth of AMOLED display panels, the panel makers have accel- erated their investment in the equipment to produce AMOLED panels.
There are three types of thin-film-transistor devices for display: amorphous silicon (a-Si), low temperature polysilicon (LTPS), and metal oxide (MO), also known as transparent amorphous oxide semiconductor (TAOS). AMLCD panels typically use a-Si for lower-resolution displays and TVs while high-resolution displays use LTPS transistors, but this use is mainly limited to small and medium displays due to its higher costs and scalability limitations. AMOLED panels use LTPS and MO transistors where MO devices are typically used for TV and large displays (FIGURE 3).
This shift in technology also requires a change in the gases used in production of AMOLED panels as compared with the AMLCD panels. As shown in FIGURE 4, display manufacturing today uses a wide variety of gases.
Nitrogen trifluoride: NF3 is the single largest electronic material from spend and volume standpoint for a-Si and LTPS display production while being surpassed by N2O for MO production. NF3 is used for cleaning the PECVD chambers. This gas requires scalability to get the cost advantage necessary for the highly competitive market.
Nitrous oxide: Used in both LTPS and MO display production, N2O has surpassed NF3 to become the largest electronic material from spend and volume standpoint for MO production. N2O is a regional and localized product due to its low cost, making long supply chains with high logistic costs unfeasible. Averaging approximately 2 kg per 5.5 m2 of mother glass area, it requires around 240 tons per month for a typical 120K per month capacity generation 8.5 MO display production. The largest N2O compressed gas trailer can only deliver six tons of N2O each time and thus it becomes both costly and risky
Individual packages: Specialty gases are supplied in individual packages. For higher volume materials like silane and nitrogen trifluoride, these can be supplied in large ISO packages holding up to 10 tons. Materials with smaller requirements are packaged in standard gas cylinders.
In-fab distribution: Gas supply does not end with the delivery or production of the material of the fab. Rather, the materials are further regulated with additional filtration, purification, and on-line analysis before delivery to individual production tools.
To facilitate these increasing demands, display manufacturers must partner with gas suppliers to identify which can meet their technology needs, globally source electronic materials to provide customers with stable and cost- effective gas solutions, develop local sources of electronic materials, improve productivity, reduce carbon footprint, and increase energy efficiency through on-site gas plants. This is particularly true for the burgeoning China display manufacturing market, which will benefit from investing in on-site bulk gas plants and collaboration with global materials suppliers with local production facilities for high-purity gas and chemical manufacturing.
Flat panel displays use different backplane technologies. Small and medium OLEDs for mobile phones use a low temperature polysilicon (LTPS) backplane which is created by laser annealing amorphous silicon (a-Si). OLED TVs use a metal oxide backplane. Both backplanes use deposited thin films which must be highly uniform and contamination free to maximize electrical performance. The OLEDs are evaporated or deposited and encapsulated to reduce degradation caused by water vapor and oxygen exposure. Encapsulation uses either strengthened glass or thin films, depending on whether the OLED is rigid or flexible. Dissimilarity of materials within the rigid and flexible stacks make cutting and singulation of individual display devices a challenge. The highly complex nature of this process can induce defects, decreasing throughput and yield.
RGB pixels are evaporated on the LTPS backplane surface using an invar Fine Metal Mask (FMM). As OLED manufacturers push for >1000 pixels per inch (PPI) to support VR, a new way to create a fine metal mask with increased pixel density and feature accuracy is necessary. Our Micromachining Lasers, with picosecond or femtosecond pulses and small, focused beam widths, create completely vertical pixel holes with no material buildup that could negatively impact feature geometry. Ultrashort pulses reduce excess heat buildup providing a minimal heat affected zone. This reduces mask warp and ensures all pixel holes maintain their shape. The laser’s high output power, high beam quality and narrow bandwidth supports highly uniform beam splitting for parallel machining and increased throughput.
Our industrial femtosecond and picosecond display manufacturing lasers are excellent for glass and film cutting. For cover glass and rigid OLED, they provide flexible pulse and burst control with precision, resulting in a micro-crack, chip-free edge, making the glass stronger and less likely to break if dropped. This reduces the need for post-cut polishing, increasing throughput by reducing the number of manufacturing process steps. For flexible OLEDs, Spectra-Physics lasers with short pulse widths create a minimal heat affected zone and provide a clean cut through layers of dissimilar materials including various thin films, PET, and adhesives. Increased throughput is achieved from higher output power that speeds up the cutting process. The narrow kerf or cut and the low heat affected zone means more parts can be cut out of the same material.
The cutting-edge G10 production line is a result of cutting-edge technology. To consistently manufacture LCD panels using the G10 glass substrates, each individual manufacturing process incorporates a range of unique know-how. Developed in collaboration with several world-leading production equipment manufacturers, SDP"s large-scale, one-of-a-kind manufacturing equipment delivers state-of-the-art accuracy and performance levels. One example is the photolithography machine, which is about the size of a tennis court. Our master-craftsmen operate and monitor this machine with the utmost care, to manufacture next-generation products.
In the design of the substrate, photolithography is used to form circuits and wiring. First, a coater system is used to apply photosensitive material—called “photoresist”—rapidly and uniformly across the entire glass substrate. Next, using a photolithography machine, the glass substrate is irradiated with ultraviolet light, transferring onto it a high-precision TFT pattern via a mask. A developing system uses developer fluid to dissolve and remove the photoresist previously applied using the photolithography machine, and only the resist that forms the TFT pattern remains.
In recent time, China domestic companies like BOE have overtaken LCD manufacturers from Korea and Japan. For the first three quarters of 2020, China LCD companies shipped 97.01 million square meters TFT LCD. And China"s LCD display manufacturers expect to grab 70% global LCD panel shipments very soon.
BOE started LCD manufacturing in 1994, and has grown into the largest LCD manufacturers in the world. Who has the 1st generation 10.5 TFT LCD production line. BOE"s LCD products are widely used in areas like TV, monitor, mobile phone, laptop computer etc.
TianMa Microelectronics is a professional LCD and LCM manufacturer. The company owns generation 4.5 TFT LCD production lines, mainly focuses on making medium to small size LCD product. TianMa works on consult, design and manufacturing of LCD display. Its LCDs are used in medical, instrument, telecommunication and auto industries.
TCL CSOT (TCL China Star Optoelectronics Technology Co., Ltd), established in November, 2009. TCL has six LCD panel production lines commissioned, providing panels and modules for TV and mobile products. The products range from large, small & medium display panel and touch modules.
Established in 1996, Topway is a high-tech enterprise specializing in the design and manufacturing of industrial LCD module. Topway"s TFT LCD displays are known worldwide for their flexible use, reliable quality and reliable support. More than 20 years expertise coupled with longevity of LCD modules make Topway a trustworthy partner for decades. CMRC (market research institution belonged to Statistics China before) named Topway one of the top 10 LCD manufactures in China.
Established in 2013, Eternal Material Technology is committed to the research, development and manufacturing of electronic materials and providing technical services. EMT is leading the industry with its products of OLED and color photoresist materials.
The Company engages in the R&D, manufacturing, and sale of LCD panels. It offers LCD panels for notebook computers, desktop computer monitors, LCD TV sets, vehicle-mounted IPC, consumer electronics products, mobile devices, tablet PCs, desktop PCs, and industrial displays.
One of today’s modern technological wonders is the flat-panel liquid crystal display (LCD) screen, which is the key component we find inside televisions, computer monitors, smartphones, and an ever-proliferating range of gadgets that display information electronically.What most people don’t realize is how complex and sophisticated the manufacturing process is. The entire world’s supply is made within two time zones in East Asia. Unless, of course, the factory proposed by Foxconn for Wisconsin actually gets built.
Liquid crystal display (LCD) screens are manufactured by assembling a sandwich of two thin sheets of glass.On one of the sheets are transistor “cells” formed by first depositing a layer of indium tin oxide (ITO), an unusual metal alloy that you can actually see through.That’s how you can get electrical signals to the middle of a screen.Then you deposit a layer of silicon, followed by a process that builds millions of precisely shaped transistor parts.This patterning step is repeated to build up tiny little cells, one for each dot (known as a pixel) on the screen.Each step has to be precisely aligned to the previous one within a few microns.Remember, the average human hair is 40 microns in diameter.
On the other sheet of glass, you make an array of millions of red, green, and blue dots in a black matrix, called a color filter array (CFA).This is how you produce the colors when you shine light through it.Then you drop tiny amounts of liquid crystal material into the cells on the first sheet and glue the two sheets together.You have to align the two sheets so the colored dots sit right on top of the cells, and you can’t be off by more than a few microns in each direction anywhere on the sheet.The sandwich is next covered with special sheets of polarizing film, and the sheets are cut into individual “panels” – a term that is used to describe the subassembly that actually goes into a TV.
For the sake of efficiency, you would like to make as many panels on a sheet as possible, within the practical limitations of how big a sheet you can handle at a time.The first modern LCD Fabs built in the early 1990s made sheets the size of a single notebook computer screen, and the size grew over time. A Gen 5 sheet, from around 2003, is 1100 x 1300 mm, while a Gen 10.5 sheet is 2940 x 3370 mm (9.6 x 11 ft).The sheets of glass are only 0.5 - 0.7 mm thick or sometimes even thinner, so as you can imagine they are extremely fragile and can really only be handled by robots.The Hefei Gen 10.5 fab is designed to produce the panels for either eight 65 inch or six 75 inch TVs on a single mother glass.If you wanted to make 110 inch TVs, you could make two of them at a time.
The fab is enormous, 1.3 km from one end to the other, divided into three large buildings connected by bridges.LCD fabs are multi-story affairs.The main equipment floor is sandwiched between a ground floor that is filled with chemical pipelines, power distribution, and air handling equipment, and a third floor that also has a lot of air handling and other mechanical equipment.The main equipment floor has to provide a very stable environment with no vibrations, so an LCD fab typically uses far more structural steel in its construction than a typical skyscraper.I visited a Gen 5 fab in Taiwan in 2003, and the plant manager there told me they used three times as much structural steel as Taipei 101, which was the world’s tallest building from 2004- 2010.Since the equipment floor is usually one or two stories up, there are large loading docks on the outside of the building.When they bring the manufacturing equipment in, they load it onto a platform and hoist it with a crane on the outside of the building.That’s one way to recognize an LCD fab from the outside – loading docks on high floors that just open to the outdoors.
LCD fabs have to maintain strict standards of cleanliness inside.Any dust particles in the air could cause defects in the finished displays – tiny dark spots or uneven intensities on your screen.That means the air is passed through elaborate filtration systems and pushed downwards from the ceiling constantly.Workers have to wear special clean room protective clothing and scrub before entering to minimize dust particles or other contamination.People are the largest source of particles, from shedding dead skin cells, dust from cosmetic powders, or smoke particles exhaled from the lungs of workers who smoke.Clean rooms are rated by the number of particles per cubic meter of air.A class 100 cleanroom has less than 100 particles less than 0.3 microns in diameter per cubic meter of air, Class 10 has less than 10 particles, and so on. Fab 9 has hundeds of thousands of square meters of Class 100 cleanroom, and many critical areas like photolithography are Class 10.In comparison, the air in Harvard Square in Cambridge, MA is roughly Class 8,000,000, and probably gets substantially worse when an MBTA bus passes through.
The Hefei Gen 10.5 is one of the most sophisticated manufacturing plants in the world.On opening day for the fab, BOE shipped panels to Sony, Samsung Electronics, LG Electronics, Vizio, and Haier.So if you have a new 65 or 75-inch TV, there is some chance the LCD panel came from here.
We have thousands of standard products that are in stock and available from our Seattle, WA and Hong Kong warehouses to support fast product development and preproduction without MOQ. The stock covers TN, STN LCD display panels, COB, COG character LCD display, graphic LCD display, PMOLED, AMOLED display, TFT display, IPS display, high brightness and transflective, blanview sunlight readable display, super high contrast ratio display, lightning fast response displays, efficient low power consumption display, extreme temperature range display, HMI display, HDMI display, Raspberry Pi Display, Arduino display, embedded display, capacitive touch screen, LED backlight etc. Customers can easily purchase samples directly from our website to avoid time delays with setting up accounts and credit terms and shipping within 24 hours.
Many of our customers require customized OEM display solutions. With over two decades of experience, we apply our understanding of available display solutions to meet our customer’s requirements and assist from project concept to mass production. Using your ideas and requirements as a foundation, we work side by side with you to develop ideas/concepts into drawings, build prototypes and to final production seamlessly. In order to meet the fast changing world, we can provide the fastest turnaround in the industry, it takes only 3-4 weeks to produce LCD panels samples and 4-6 weeks for LCD display module, TFT LCD, IPS LCD display, and touch screen samples. The production time is only 4-5 weeks for LCD panels and 5-8 weeks for LCD display module, TFT LCD, IPS LCD display, and touch screen.
Liquid crystal displays are commonly known as LCD, consist of liquid crystals that are activated by electric current, and they are used to display lines of alpha-numeric information (one or more lines) in a variety of devices, for example, fax machines, answering machines call counters, laptop computer screens, scientific instruments, portablecompact disc players,clocks, and so forth. The basis of LCD technology is the liquid crystal, a substance made of complicated molecules.
LCD uses a liquid crystal to produce a visible image. Liquid crystal displays are super-thin technology display screens that are generally used in laptop computer screens, TVs, cell phones, and portable video games.Liquid crystal displays (LCDs) have become the dominant technology in televisions and monitors in our homes and offices.
In an LCD, an electric current is used to switch segments of liquid crystals from a transparent phase to a cloudy phase, each segment forming part of a number or letter. The segments can also be in the shape of tiny dots or pixels, and they can be arranged in rows and columns. They are turned on and off individually to either block or allow polarized light to pass through. When the light is blocked, a dark spot is created on the reflecting screen.
Liquid crystal display (LCD) screens are manufactured by assembling a sandwich of two thin sheets of glass. On one of the sheets are transistor “cells” formed by first depositing a layer of indium tin oxide (ITO), an unusual metal alloy that you can actually see through. That’s how you can get electrical signals to the middle of a screen. Then you deposit a layer of silicon, followed by a process that builds millions of precisely shaped transistor parts. This patterning step is repeated to build up tiny little cells, one for each dot (known as a pixel) on the screen. Each step has to be precisely aligned to the previous one within a few microns. Remember, the average human hair is 40 microns in diameter.
On the other sheet of glass, you make an array of millions of red, green, and blue dots in a black matrix called a color filter array (CFA). This is how you produce the colors when you shine light through them. Then you drop tiny amounts of liquid crystal material into the cells on the first sheet and glue the two sheets together. You have to align the two sheets so the colored dots sit right on top of the cells, and you can’t be off by more than a few microns in each direction anywhere on the sheet. The sandwich is next covered with special sheets of the polarizing film, and the sheets are cut into individual “panels” – a term that is used to describe the subassembly that actually goes into a TV.
Generally, a brush is used toscrubat the same time to enhance the stripping effect. Then use DI water to clean and dry the glue crumbs. Generally, the above processes are calledlithography processes, which play a key role in LCD manufacturing.
Generally, the orientation materials for the production of low- and medium-grade LCDs are made of PA, that is, polyimide acid, which is made by the polymerization reaction of dianhydride and diamine at low temperature. It is dehydrated and cured at high temperature (the upper chemical layer is a kind of ring Chemical reaction), it becomes polyimide (PI). Polyimide has good chemical stability, excellent mechanical properties, high insulation, high-temperature resistance, high dielectric constant, radiation resistance, and non-flammability.
Screen printing is a technology, where the print material is pressed by a squeegee through a mesh that is fixed on a frame. The mesh carries a photoresist layer with openings defining the pattern to be printed.
Flexo printing is offered in order to form polyimide layers in glass plates for LCD manufacturing. We can integrate these machines in an in-line production street or in a polyimide cluster, consisting of a polyimide printing machine, a coupled hot plate curing system and related automation incl. loading and unloading devices.
Use flannel materials to rub the surface of the alignment layer in a specific direction so that the liquid crystal molecules can be aligned along the rubbing direction of the alignment layer in the future.
Punctuation silkscreen is used to connect the circuits of the LCD because there are 2 glasses of the LCD. up one and down. Only the pin side glass has an electricity connection, that dots are for supplying electricity for the glass which doesn’t have electricity. that dots are for supplying electricity for the glass which doesn’t have electricity.
As described above already, the seal has to be finally cured after the cell assembly process. This has to be done under pressure in order to make sure that the seal thickness is properly related to the spacer diameter and the calculated liquid crystal thickness can be reached with low tolerances. Hotpress ovens are available as a batch process tool and as a single panel press oven. The batch oven requires a previous collection of panels and preparation of a larger pile of panels that are pressed together. The pressed pile of wafers is then cured in a clean convection oven. The single panel hot press oven is easier to integrate with automatic lines and works continuously.
Usually, a pair of ITO glasses can make multiple liquid crystal cells. In order to expose the LCD filling port, the glass must be appropriately cut into strips or granules.
This stage includes filling the liquid crystal into the prepared empty cell and sealing the filling hole so that the liquid crystal cell is basically made. Generally, a special liquid crystal filling machine is used to form a vacuum in the liquid crystal cell, and then the liquid crystal is filled into the LCD cell by the pressure difference and the capillary action of the liquid crystal cell.
Use a sealing material (such as a sealing resin) to block the opening of the filled liquid crystal box. Wipe clean the liquid crystal on the sealing surface of the filled LC liquid crystal box, apply a certain amount of UV sealing glue, and then irradiate it with ultraviolet rays to cause the glue itself to chemically react and interact.Coupling and polymerizationto form a firm seal to prevent the liquid crystal in the screen from leaking to the outside, and also prevent external contaminants from intruding into the liquid crystal in the screen.
Detection Visuallyinspects the appearance and background color of semi-finished LCD products under the polarized light table and picks out the unqualified products.
The electrical testis to check the display graphics, electrical and functional defects, and other appearance defects of the LCD screen under the power-on state.
This is the most important point in LCD manufacturing, where silkscreens are used for printing. High-resolution silkscreens have more than 130 meshes per cm, enabling them to print lines with a width down to 50µm. The layer thickness is in the range of 10µm normally, which is regarded as a “thick” layer in LCD manufacturing.
For creating the image, the mesh is coated by a photosensitive emulsion, which is exposed using a mask, made from a glass or polymer film. The unexposed portion of the coating is washed off afterward. This portion lets the seal material go through and you have its pattern on the substrate.
Adhesive force enhancement. This surface improvement is used for various materials like plastics, metals, and inorganic compounds. It can be used for many applications e.g before like aquarium tank sealing, sticking or mounting plastic parts or rubbers, before attachment of aluminum foils in micro condensers, mounting of magnetic heads, semiconductor lead frames, etc.
VISLCD has been engaged in LCD production and sales for 9 years, and we have met many customers who shared with us that they had encountered unreliable LCD suppliers.
For example, the answer is not what you asked for, the LCD product cannot be delivered on time, the price of the LCD suddenly increases, the LCD module suddenly breaks down during the use of the product, or even the LCD is discontinued after less than 1 year of delivery…etc. In addition, there are many customers who are not sure what type of LCD supplier they are looking for.
In view of all the above, VISLCD has written this article to share knowledge about LCD suppliers and other issues related to LCD. We believe it will be helpful to LCD customers.
To understand LCD suppliers, we first need to know what kinds of LCD suppliers are available. Then LCD customers can find the right supplier based on information such as their product applications, LCD requirements and forecast volume.
LCD original manufacturer refers to the original manufacturer of LCD panel. Originated from the USA in the 1960’s, after more than 50 years of development, the manufacturers are now mainly located in China mainland, Korea and Taiwan. Among them, the Chinese manufacturers in recent years rely on the rapid scale, technology development and price advantage, has gradually occupied the main market share.
The video below is an official video presentation of the BOE display factory and Century Display (CTC), which will give you a more visual understanding of the original LCD manufacturer.
The 5.1 generation TFT-LCD line of Century Display in Shenzhen, China, for example, has been put into operation since 2008 with a cumulative fixed investment of more than $4 billion, and the cost of water, electricity, employee wages and equipment depreciation is as high as $0.5~100 million/month. The monthly production capacity is about 100,000 sheets ( 1300*1200mm/sheet). If all of them are used to produce 7-inch LCD panels, then the monthly shipment volume is up to 9,000,000 pcs. Therefore, a very large monthly shipment volume is required to meet the normal operation of the factory.
This is only the 5.1 generation TFT-LCD line, if it is 8.5 generation line or even 10 generation line or more, then the cost and shipment volume may be several times or even ten times more. It should be noted that the number of generations of LCD lines does not mean that the technology is high or low. The higher the generation, then the larger the size of the LCD can be put into production, of course, the greater the volume of shipments and investment amount.
LCD original manufacturers generally provide mainly LCD panels, but also provide COG (LCD + IC), FOG (LCD + IC + FPCA cable) and other kinds of LCD semi-finished products. Also includes a small amount of the original LCD module. But the original LCD factory will only deal with the famous brand companies directly (such as Apple, Dell, Xiaomi, etc.), or through agents to ship. And the MOQ quantity requirement is very high (generally 1,000,000 pcs/month or more), the unit price of original LCD module is also high and the degree of customization is low.
LCD original manufacturers usually have an order MOQ requirement for their agents, which translates into an LCD unit quantity of no less than 100,000pcs/month. When the LCD demand is high, this will not be a problem; but when the market is low, the agent must buy the agreed MOQ quantity of LCD from the original LCD manufacturer even if there is no customer demand for the time being. So when the low season, if your order quantity is large enough, then you may get a very good LCD panel price from the LCD agent, which may even be lower than the agent’s purchase price.
LCD module manufacturers is to purchase LCD semi-finished products (such as LCD panel, COG or FOG) from LCD agents, then purchase ICs from IC agents, produce or purchase backlight, FPCA cable and touch screen components, and then integrate all the above components into LCD module or touch LCD module. LCD module factories vary in size from tens of millions of pcs to hundreds of thousands of pcs shipped per month.
Medium and large size module factory generally get the semi-finished products are FOG LCD (also known as open cell LCD) from the original LCD manufacturers or LCD agents, and then add the backlight assembly into the finished LCD module. The advantage of doing so is that the quality is relatively stable, but the degree of customization will be much lower. Because FOG LCD already includes FPCA cable, generally speaking, the only thing that can be customized is the brightness of the backlight and the touch panel and cover glass (if needed). The rest are difficult to change, unless the customer’s LCD demand is very large.
The small and medium size module factory after years of mature development of the industry, the degree of customization will be much more flexible. The semi-finished products are mainly LCD panels, which means that the backlight size, backlight brightness, FPCA cable design, shape and PIN number, as well as the touch panel and cover glass can all be customized according to the customer’s requirements. But the MOQ requirement is higher for the backlight size. Other parts of the customization generally require LCD MOQ of at least 2,000~5,000 pcs, which varies depending on the LCD size.
Since LCD module manufactures vary in size and quality control(especially small and medium size LCD module factories), and most of the components are sourced, the selection of module factories is particularly important if customers want to buy LCDs with good quality and competitive prices.
For example, if the factory’s customers are mostly low-cost products or repaired product manufacturers, then it can be assumed that the quality of his products is not too good, LCD panels and some other components may be B-grade products, not A, can only meet short-term use.
This is essential to ensure supply. In case of supply shortage, many module factories with insufficient upstream channels sometimes cannot even start production. Because they can not buy raw materials such as LCD panels and ICs.
As the name implies, trading companies do not have their own factories, but directly sell finished LCD products from LCD resellers or LCD modules from module manufacturers. Generally speaking, the LCD prices of trading companies are relatively high and the quality and reliability are a little weaker. However, there is no shortage of good trading companies with good quality management teams and good upstream channel resources. The biggest advantage of trading companies is their flexibility, which can meet the diversified needs of customers.
2) Shenzhen has 3 types of buildings related to lcd (including other electronic products): office buildings, factories and markets. Almost all LCD panel and IC agents are located in various office buildings in Shenzhen, while component factories such as FPCA, Touch panel and backlight are located in various industrial parks in the suburbs. It is possible to find the right components and develop new products in the shortest time. Of course, there is also the famous Huaqiang bei(north) Electronic Market, a very complex place.
VISLCD was a trading company in the early days. But after nearly 9 years of development, it has developed into a combination of LCD module factory and LCD agent. The company is located in LCD base Shenzhen, China and operates in both Hong Kong and Shenzhen. We have our own module factory and have direct relationship with Century Display, LG, HKC and other LCD original manufacturers. Our main employees are also from these LCD manufacturers. We also accept all kinds of customized LCD business. Therefore, VISLCD is one of the best choices for medium-sized customers in terms of quality stability, semi-finished parts supply and customization.