Composition and Working Principle of LED Display Screen

In this paper, LED display screen is composed of several display units (unit display board or unit display box) that can be combined and spliced, plus a set of appropriate controller (main control board or control system). Therefore, a variety of display boards (or unit boxes) with different control technologies can form many kinds of LED displays to meet the needs of different environments and display requirements.

1 Main composition of LED display screen (taking the more complex synchronous full-color screen as an example)

1. The metal structure frame is used to form an inner frame and carry various circuit boards such as display unit board or module and switching power supply

2. Display unit: it is the main part of LED display screen, which is composed of LED lamp and driving circuit. The indoor screen is the unit display board of various specifications, and the outdoor screen is the module box.

3. Scanning control board: the function of the circuit board is data buffer to generate various scanning signals and duty cycle gray control signals.

4. Switching power supply: change 220V AC into various DC to supply various circuits.

5. Transmission cable: the display data and various control signals generated by the main controller are transmitted to the screen body by twisted pair cable.

6. Main controller: buffer the input RGB digital video signal, transform the gray level, reorganize it, and generate various control signals.

7. Special display card and multimedia card: in addition to the basic functions of computer display card, it also outputs digital RGB signals and line, field, blanking and other signals to the main controller. In addition to the above functions, multimedia can also change the input analog video signal into digital RGB signal (i.e. video acquisition).

8. Computer and its peripherals

Figure 1 LED display system composition

2 Analysis of main functional modules

1. Video broadcast

Through multimedia video control technology and VGA synchronization technology, various forms of video information sources can be easily introduced into the computer network system, such as radio and satellite TV signals, camera video signals, VCD video signals of video recorders, computer animation information, etc. Therefore, the following functions can be realized:

Support VGA display and display various computer information, graphics and images.

Support various input modes; Support pal, NTSC and other systems.

Display color video images in real time to realize on-site broadcasting.

Broadcast radio and television, satellite television and cable television signals.

Real time playback of video signals such as TV, camera and video disc (VCR, VCD, DVD and LD).

It has the function of playing pictures and words with different proportions on the left and right at the same time

2. Computer broadcast

Graphic stunt display function: it has the functions of editing, zooming, flowing and animation.

Display various computer information, graphics, images and 2D and 3D computer animation and overlay text.

The broadcasting system is equipped with multimedia software, which can flexibly input and broadcast a variety of information.

There are a variety of Chinese fonts and fonts to choose from. At the same time, you can also input English, Spanish, French, German, Greek, Russian, Japanese and other languages.

There are many broadcast modes, such as single / multiple line translation, single / multiple line up / down, left / right pull, up / down, rotation, stepless zoom, etc.

Editing, broadcasting and instant release of notices, announcements, announcements and news, and there are a variety of fonts to choose from.

3. Network function

Equipped with standard network interface, it can be connected with other standard networks (information query system, Municipal Publicity network system, etc.).

Collect and broadcast real-time data of each database to realize remote network control.

You can access the Internet through the network system

It has a sound interface, which can be connected to audio equipment to achieve audio-visual synchronization.

4. Screen controller

The screen controller controls the display effect of its corresponding display screen. It can automatically run a continuous cycle program to obtain relevant display data according to the given program list, or it can intervene manually to produce the display effect on the screen. The pixels on the screen are directly mapped with the pixels on the corresponding area of the screen controller display.

The screen controller can manually adjust the brightness of the display screen and select the gray nonlinear correction data suitable for the current environment. The screen controller can also automatically adjust the brightness of the display screen and select different gray nonlinear correction data according to the ambient brightness through the network system.

The contrast and chroma of image display can be adjusted through the screen control machine. The screen controller transmits the information to be displayed to the video processing and control unit for video processing.

5. Video processing and control unit

The video processing and control unit completes the image processing of the display data, including:

The second level of gray nonlinear correction can be adjusted automatically or manually.

Automatic or manual stepless brightness adjustment.

The gray level control system can control the display screen to display 24 bit data of 8 bits of each primary color, that is, 256 gray levels of each primary color.

Image noise reduction processing to ensure that the image is cleaner and smoother.

Image enhancement technology, image edge enhancement technology.

Motion compensation technology, chroma adjustment function.

6. Visual processing

In the system, the brightness of each primary color of a single module can be adjusted respectively, the color balance can be adjusted, and the mosaic phenomenon can be basically eliminated. The brightness consistency of all modules and display modules is good, and the monochrome display has no visual difference.

The video processing and control unit transmits the processed display information to the communication module for long-distance transmission to the display screen.

7. Communication module

The communication module ensures that the display content of the screen control machine is accurately transmitted to the display screen for a long distance. The communication module encodes and decodes the transmitted information, and processes the long-distance transmission and reception data. The communication module transmits the display information to the data distribution and scanning unit.

The LED display screen is usually composed of the main controller, the scanning board, the display control unit and the LED display screen body. The main controller obtains the color brightness data of each pixel of a screen from the computer display card, and then assigns it to several scanning boards. Each scanning board is responsible for controlling the dry lines (columns) on the LED display screen, and each line (column) The LED display signal on the is transmitted in series through each display control unit of the bank, and each display control unit directly faces the LED display body. The work of the main controller is to convert the signal of the computer display card into the data and control signal format required by the LED display screen. The function of display control unit operation is similar to that of image display screen. It is generally composed of shift register latch with gray level control function. However, the scale of video LED display is often larger, so we should use integrated circuits with larger integration scale. The function of the scanning plate is the so-called connecting link. On the one hand, it receives the video signal of the main controller, on the other hand, it transmits the data belonging to the current level to its own display control units, and also transmits the data not belonging to the current level to the next cascade scanning plate. The differences between video signals and LED display data in space, time, sequence and other aspects need to be coordinated by a scanning board.

Composition and Working Principle of LED Display Screen 1

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The minimum viewing distance and the best viewing distance are very close to the viewing requirements of large flat panel TV, and the whole screen resolution is up to 4800 2400, clearer pictures can be displayed on the same screen body, but one HD signal needs to be amplified by 3 4 times on a 12m wide screen, and two HD pictures need to be amplified by 2 times; At the same time, high-resolution display requires high-performance image processing equipment, and the overall cost of the system will be very high.P4 and p4.8 cannot display two high-definition pictures at the same time on a 12m wide screen, which can not meet the display requirements of high-definition conference TV pictures. P3 can meet the requirements of displaying two high-definition pictures at the same time. 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It is mainly used for the production of high-end LED displays with small spacing and high density.Three in one surface sticker (separate surface sticker) refers to that the three light-emitting points of red, green and blue are packaged separately. After packaging, they are arranged into one pixel point, and then packaged with a mask for protection, which can prevent dust and scratch, and protect the light-emitting chip. Three in one is the separation of table stickers, three-point separate power supply, low power consumption, single lamp maintenance and low cost.Generally speaking, in order to improve the display effect of indoor screen, three in one surface paste, black light technology, gold wire packaging, etc. are selected.The LED control part is the core part to determine the display effect. The control circuit has a high-performance single-chip micro control chip. The controller sends the control signal and data to the LED driver chip through the internal control program. After receiving the signal, the LED driver chip generates the corresponding action, so as to realize the independent control of each red, green and blue LED light-emitting chip.1. Drive systemThe function of the LED driving part is to receive color data and drive the LED display screen to display according to the brightness value represented by the data. There are usually three modes: constant current, voltage stabilization and constant voltage constant current.The output current of the constant current drive circuit is constant, and the output DC voltage changes with the change of load resistance. The whole circuit is not afraid of load short circuit, but it is strictly prohibited to open the load completely. The voltage stabilizing circuit outputs a fixed voltage, and the output current changes with the increase or decrease of the load. The whole circuit is not afraid of open circuit of the load, but it is strictly prohibited to completely short circuit the load. The first constant voltage and then constant current mode is the most ideal driving circuit. It not only detects the LED current, but also controls the LED voltage, which is conducive to improving the LED life and reducing the power consumption. It is generally used in high-grade LED products.2. Control systemThe display effect of stage LED display screen depends on the size and time of current and voltage through it, so the control system mainly controls the power output of LED. At present, the LED power supply designed by PWM (pulse modulation) control mode has a conversion efficiency of 80% 90%, and the output voltage or current is very stable. It is a high reliability power supply.PWM can control the time ratio of LED on and off. By dividing the time ratio into several levels, the LED displays a corresponding number of gray levels (gray scales). 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Generally, there are three modes: series, parallel and hybrid. Series connection is a connection method with low reliability, which is often used in low-end products. In the voltage stabilizing driving circuit, when a LED is short circuited, the voltage distributed to other LEDs will rise, which is easy to cause more damage.The parallel mode is applicable to products with low power supply voltage. In the constant current drive circuit, when one LED is disconnected, the current distributed to other LEDs will increase, which is easy to damage all LEDs in the circuit.At present, in order to improve the reliability of products, the mixed connection mode is generally adopted. The number of series and parallel LEDs is evenly distributed, grouped and connected in parallel, and then each group is connected in series. In this way, the voltage distributed on a series of LEDs is the same, the current through each LED is basically the same, and the LED brightness is the same. At the same time, it is best to add LED temperature negative feedback in the constant current output to prevent the LED temperature from being too high.The whole display screen is spliced by multiple module units. In order to ensure the reliability of power supply and data, hybrid connection must also be adopted to realize the loop backup function. When an abnormal fault occurs in one power supply, other power supplies will automatically conduct intelligent current sharing, so as not to affect the normal use of the system and more effectively improve the fault-free operation time of the system, Reduce failure maintenance time.4 Special requirements for screen body of stage cameraAlthough the high refresh rate can ensure that even under the shooting of high-speed camera, the large screen can still respond in time, and the picture conversion and transition are smoother and smoother; However, in the process of use, it will be found that when the camera lens is aimed at the LED display screen, inexplicable water wave like stripes and strange colors occasionally appear, and the water wave will change with the change of shooting angle and the adjustment of camera lens focal length, which will affect the display effect of live broadcast and recording, This is the moire phenomenon brought about by the digitization of TV camera.If the spatial frequency of the CCD (or CMOS) pixel of the photosensitive element is close to the spatial frequency of the (LED) stripe in the image, a molar stripe will be generated. Since the moire phenomenon is caused by the inherent structure of LED display screen, if one of the conditions for the generation of Moire - the grid structure of LED display screen or the grid structure of camera CCD (CMOS) disappears, the moire interference can be completely eliminated in theory.Domestic companies superimpose a layer of optical processing screen on the surface of LED display screen, which is composed of specific proportion of special light absorbing material and surface bead lens coating. Through the use of optical screen, the LED screen changes from grid light to continuous surface light. Through the amplification and display of discrete LED pixels, a continuous high-definition image is finally formed on the surface of optical processing screen, While improving the contrast, it retains high definition and eliminates the moire phenomenon.
Four Factors to Be Considered in the Design Scheme of Stage LED Display Screen
Four Factors to Be Considered in the Design Scheme of Stage LED Display Screen
Before the implementation of the stage rental LED display screen project, it is necessary to make a design scheme, especially when designing the screen body, it is necessary to consider important factors such as the display screen model, display content, installation site environment and cost, and ensure that the production process and technical indicators are suitable for the actual indoor application needs, so as to carry out reasonable design.The sense of visual graininess mainly comes from the fact that the human eye has a certain resolution. When the two points are close to a certain extent, the human eye will not be able to distinguish them. In recent two years, with the improvement of LED display manufacturing technology, the body resolution of Maipu Guangcai small spacing LED display has been continuously improved, and the indoor display design has been improved from the initial selection of the minimum point distance specification scheme to the selection of the appropriate point distance specification scheme.Pixel spacing is the distance between lamp beads, for example, P3 pixel spacing is 3mm; The minimum sight distance is the distance that human eyes can't distinguish pixel particles, but this distance will damage vision if viewed for a long time; The most Jia viewing distance is the comfortable distance to watch the screen, and it is also the clearest distance; The pixel density is the screen definition index. The larger the value, the higher the screen definition; Full HD image and video, screen 16:9 yellow Jin ratio, human vision is the most Hao.According to the analysis in the above table, the rental LED display screens of p1.27, p1.54, P1.6, p1.9 and p2.5 are Maipu Guangcai small spacing LED display screens (point spacing less than 2.5mm). The minimum viewing distance and the most Jia viewing distance are very close to the viewing requirements of large flat panel TV, and the whole screen resolution is up to 4800 2400, clearer pictures can be displayed on the same screen body, but one HD signal needs to be amplified by 3 4 times on a 12m wide screen, and two HD pictures need to be amplified by 2 times; At the same time, high-resolution display requires high-performance image processing equipment, and the overall cost of the system will be very high.P4 and p4.8 cannot display two high-definition pictures at the same time on a 12m wide screen, which can not meet the display requirements of high-definition conference TV pictures. P3 can meet the requirements of displaying two high-definition pictures at the same time. According to the size of the display screen, P3 with high cost performance is finally selected as the display point distance of the main screen and auxiliary screen of the project, and P4 is selected as the display point distance of the monogram screen.One factor that determines the quality of LED is the main materials, such as chip, bracket, glue (epoxy resin), gold wire, etc. the other factor is the packaging process. Pixel packaging technology is related to the color saturation, viewing angle and other display effects of the whole display screen, production cost and quality stability. It is one of the key indicators for selecting LED display screen.The mainstream indoor LED packaging technologies mainly include in-line dip and SMD mode. The in-line module encapsulates the light-emitting tube into a square shape, and then puts the red, green and blue tubes together to make a pixel module, which is directly inserted and welded on the PCB board. The process is relatively simple, the cost is low and the defect rate is high. It is mainly used in outdoor display screens. Surface pasting refers to pasting the encapsulated light-emitting tube on the circuit board, and then processing the integrated circuit welding process into a screen body. It has good heat dissipation and uniform color, and the whole display screen can be maintained in the front, which greatly reduces the maintenance cost and difficulty; At the same time, metal compounds are filled in the packaging process, which has good color mixing effect and soft luminescence, and is more suitable for indoor application.Three in one surface sticker refers to that three light-emitting points of red, green and blue are encapsulated and synthesized in the same light-emitting tube. When you look closer, it is a point. When you zoom in, it is a line separated from the three light-emitting points. It has high requirements for materials and processes in the production process. It is mainly used for the production of high-end LED displays with small spacing and high density.Three in one surface sticker (separate surface sticker) refers to that the three light-emitting points of red, green and blue are packaged separately. After packaging, they are arranged into one pixel point, and then packaged with a mask for protection, which can prevent dust and scratch, and protect the light-emitting chip. Three in one is the separation of table stickers, three-point separate power supply, low power consumption, single lamp maintenance and low cost. Generally speaking, in order to improve the display effect of indoor screen, three in one surface paste, black light technology, gold wire packaging, etc. are selected.The LED control part is the core part to determine the display effect. The control circuit has a high-performance single-chip micro control chip. The controller sends the control signal and data to the LED driver chip through the internal control program. After receiving the signal, the LED driver chip generates the corresponding action, so as to realize the independent control of each red, green and blue LED light-emitting chip.1. The function of the LED driving part of the driving system is to receive color data and drive the LED display screen to display according to the brightness value represented by the data. There are usually three modes: constant current, constant voltage and constant current.The output current of the constant current drive circuit is constant, and the output DC voltage changes with the change of load resistance. The whole circuit is not afraid of load short circuit, but it is strictly prohibited to open the load completely. The voltage stabilizing circuit outputs a fixed voltage, and the output current changes with the increase or decrease of the load. The whole circuit is not afraid of open circuit of the load, but it is strictly prohibited to completely short circuit the load. The first constant voltage and then constant current mode is the most ideal driving circuit. It not only detects the LED current, but also controls the LED voltage, which is conducive to improving the LED life and reducing the power consumption. It is generally used in high-grade LED products.2. The display effect of the stage LED display screen of the control system depends on the size and time of the current and voltage passing through it, so the control system mainly controls the power output of the LED. At present, the LED power supply designed by PWM (pulse modulation) control mode has a conversion efficiency of 80% 90%, and the output voltage or current is very stable. It is a high reliability power supply.PWM can control the time ratio of LED on and off. By dividing the time ratio into several levels, the LED displays a corresponding number of gray levels (gray scales). The product of the gray level of the three primary colors is the number of colors that can be reproduced on the display screen in theory, which is generally 256 levels. When the number of colors reaches 16.7M, 24 bit true color information can be displayed.Generally, the frequency of PWM is greater than 100Hz, otherwise there will be flashing and scanning lines when watching. At present, the gray level of Wittem indoor rental screen is 14 bits and above, the refresh frequency is 1920hz and above, and the most Gao refresh rate in the LED industry is 6800hz. Under the normal viewfinder and rotation of the camera, the LED screen display is stable without flicker, and the gray scale is too smooth at the most Gao refresh rate without color mixing.3. As the load of the circuit, the combined LED of the driving system and the control system is connected with the circuit of the driving system and the control system, which is related to the stability of the whole display screen. Generally, there are three modes: series, parallel and hybrid. Series connection is a connection method with low reliability, which is often used in low-end products. In the voltage stabilizing driving circuit, when a LED is short circuited, the voltage distributed to other LEDs will rise, which is easy to cause more damage.The parallel mode is applicable to products with low power supply voltage. In the constant current drive circuit, when one LED is disconnected, the current distributed to other LEDs will increase, which is easy to damage all LEDs in the circuit.At present, in order to improve the reliability of products, the mixed connection mode is generally adopted. The number of LEDs in series and parallel is evenly distributed, grouped and connected in parallel, and then each group is connected in series. In this way, the voltage distributed on a series of LEDs is the same, the current through each LED is basically the same, and the LED brightness is the same. At the same time, Hao adds LED temperature negative feedback in the constant current output to prevent the LED temperature from being too high.The whole display screen is spliced by multiple module units. In order to ensure the reliability of power supply and data, hybrid connection must also be adopted to realize the loop backup function. When an abnormal fault occurs in one power supply, other power supplies will automatically conduct intelligent current sharing, so as not to affect the normal use of the system and more effectively improve the fault-free operation time of the system, Reduce failure maintenance time.4 Special requirements for screen body of stage cameraAlthough the high refresh rate can ensure that even under the shooting of high-speed camera, the large screen can still respond in time, and the picture conversion and transition are smoother and smoother; However, in the process of use, it will be found that when the camera lens is aimed at the LED display screen, inexplicable water wave like stripes and strange colors occasionally appear, and the water wave will change with the change of shooting angle and the adjustment of camera lens focal length, which will affect the display effect of live broadcast and recording, This is the moire phenomenon brought about by the digitization of TV camera.If the spatial frequency of the CCD (or CMOS) pixel of the photosensitive element is close to the spatial frequency of the (LED) stripe in the image, a molar stripe will be generated. Since the moire phenomenon is caused by the inherent structure of LED display screen, if one of the conditions for the generation of Moire - the grid structure of Maipu brilliant LED display screen or the grid structure of camera CCD (CMOS) disappears, the moire interference can be completely eliminated in theory.Domestic companies superimpose a layer of optical processing screen on the surface of LED display screen, which is composed of specific proportion of special light absorbing material and surface bead lens coating. Through the use of optical screen, the LED screen changes from grid light to continuous surface light. Through the amplification and display of discrete LED pixels, a continuous high-definition image is finally formed on the surface of optical processing screen, While improving the contrast, it retains high definition and eliminates the moire phenomenon.
Introduction to Brightness Calculation and Gray Control Method of LED Display Screen
Introduction to Brightness Calculation and Gray Control Method of LED Display Screen
The gray scale in the LED display industry can also be called LED brightness. Gray level, also known as intermediate tone, is mainly used to transmit images, pictures and videos. There are three modes: 16, 32 and 64 respectively. It uses matrix processing to process the pixels of the file into 16, 32 and 64 levels, so as to make the transmitted pictures clearer. Whether it is a full-color screen or a two-color screen, in order to display an image or animation, it is necessary to adjust the luminous gray level of each LED constituting a pixel, and the fine degree of adjustment is what we usually call the gray level.1 Brightness calculation method of display screenTaking the full-color screen as an example, the balance ratio of red, green, blue and white is usually 3:6:1Brightness of red LED: brightness (CD) / m2 points / m2 & times; 0.3 (white balance ratio accounts for 30%) 2Brightness of green LED: brightness (CD) / m2 points / m2 & times; 0.6 (white balance ratio accounts for 60%)Brightness of blue LED: brightness (CD) / m2 points / m2 & times; 0.1 (white balance ratio accounts for 10%)(1) The brightness of a single tube is obtained by knowing the brightness of the whole screen.For example: 2500 dots per square meter density, 2R1G1B, 5000 CD / m2 brightness requirement, then:Brightness of red LED: 5000 2500 & times; 0.32=0.3cd=300mcdThe brightness of green LED is 5000 2500 0.6=1.2cd=1200mcdThe brightness of blue LED is 5000 2500 0.1=0.2cd=200mcd(2) Calculate the brightness of the whole screen with known single tube brightness.For example, take p31.25, Riya tube as an example.Main tube core specifications of HSM display screen are red and greenHsm-ph-a (Riya) 180-440mcd1020-2400mcdBecause white balance and brightness ratio Red: Green: blue = 3:6:1; The ratio of white balance is matched with the brightness of green tube to other tubes. Therefore, it is as follows:From the Red: Green = 3:6, it can be seen that the brightness of the green tube is twice that of the red tube, that is, the brightness of the red tube is 2400 (blue) 2 = 1200mcd. Because there are 2 red tubes among the four red, green and blue tubes, the brightness of a single red tube is 1200 2 = 600mcdFrom the green: blue = 6:1, the brightness of the green tube is 6 times that of the blue tube, that is, the brightness of the blue tube is 2400 (blue) 6 = 400mcd, because one luminous pixel = 2 red tubes 1 green tube 1 blue tube;That is, the brightness of a pixel = 600 (red) 2 2400 (green) 400 (blue) = 3400mcd = 3.4cdBrightness per square meter = brightness of 1 luminous pixel Pixel density per square meter (number) = 3.4cd 1024 (number of pixels) = 3482cd. Calculated by 20% light loss, the actual luminous brightness should be 2785.28cd2 Method for controlling LED gray level of LED display screenNext, we will introduce two brightness control methods of LED display screen. One is to change the current flowing through the LED. Generally, the continuous working current allowed by the LED core is about 20 mA. Except that the red LED is saturated, the brightness of other LEDs is basically proportional to the current flowing; Another method is to use the visual inertia of the human eye and use the pulse width modulation method to realize the gray level control, that is, periodically change the light pulse width. As long as the repeated lighting cycle is short enough, the human eye can not feel the shaking of the luminous pixels. Because PWM is more suitable for digital control, today, when microcomputer is widely used to provide LED display content, almost all LED screens use PWM to control gray level.The control system of LED is usually composed of main control box, scanning board and display and control device. The main control box obtains the brightness data of each color of a screen pixel from the display card of the computer, and then redistributes it to several scanning boards. Each scanning board is responsible for controlling several lines on the LED screen, and the display and control signal of the LED on each line is transmitted in serial mode. At present, there are two ways of serial transmission of display control signals: one is to centrally control the gray level of each pixel point on the scanning board. The scanning board decomposes the brightness value of each row of pixels from the control box, and then transmits the turn-on signal of each row of led to the corresponding LED in the form of pulse (lit as 1, not lit as 0) in a row by row serial way to control whether it is lit or not. In this way, fewer devices are used, but the amount of data transmitted in serial is large, because in a repeated lighting cycle, each pixel needs 16 pulses under 16 gray levels and 256 pulses under 256 gray levels. Due to the limitation of device working frequency, generally, the LED screen can only achieve 16 gray levels.Another method is that the content of serial transmission of the scanning board is not the switching signal of each LED, but an 8-bit binary brightness value. Each LED has its own pulse width modulator to control the lighting time. In this way, in a repeated lighting cycle, each pixel point only needs 4 pulses under 16 gray levels and 8 pulses under 256 gray levels, which greatly reduces the serial transmission frequency. With this method of decentralized control of LED gray level, 256 gray level control can be easily realized.
Detailed Analysis on the Calculation Method of Point Spacing and Sight Distance of LED Display Scree
Detailed Analysis on the Calculation Method of Point Spacing and Sight Distance of LED Display Scree
1. Calculation method of point spacing: the center distance from each pixel to each adjacent pixel;3. Calculation method of the number of modules used for the screen: total area module length module height = the number of modules used. For example, the number of modules used for 10 square PH16 outdoor monochrome LED displays is equal to: 10 square meters 0.256 meters 0.128 meters = 305.17678 305More accurate calculation method: the length uses the number of modules The number of modules used in height = the total number of modules used, for example, the number of modules used in PH16 monochrome LED display screen with a length of 5 meters and a height of 2 meters: the number of modules used in length = 5 meters 0.256 meters = 19.53125 20, the number of modules used in height = 2 meters 0.128 meters = 15.625 16, and the total number of modules used = 20 16 = 3204. Calculation method of visual distance of LED display screen: RGB color mixing distance, distance of three colors mixing into a single color: LED full-color screen visual distance = pixel spacing (mm) 500/1000 The minimum viewing distance is the distance that can display smooth images: visual distance of LED display = pixel spacing (mm) 1000/1000 The most suitable viewing distance is the distance that the viewer can see a highly clear picture: Zui good viewing distance of LED display = pixel spacing (mm) 3000/1000Furthest viewing distance: furthest viewing distance of LED display = screen height (m) 30 (Times)In short, the improvement of the picture fineness of LED screen will gradually eliminate the image quality gap between LED screen and LCD and other display technologies in the traditional sense, so as to highlight other advantages of LED screen. Further, it will also make the LED screen no longer limited to outdoor advertising applications, but more in line with the needs of indoor deployment.fqj
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