Scanning Mode and Working Principle of LED Electronic Display Screen

key word:LED, parameter, display screenNote: the video screen can display video signals in real time, such as pictures, animation, video, TV programs, etc., but it cannot be displayed offline; Select different LED lamps according to different environments, with different viewing angles and brightness; The calculated display surface and brightness are different. f --- indoor screen; P --- outdoor panel; S --- monochrome picture and text screen; D --- dual color screen; V --- two color video screen; T --- full color video screen; T * * chip --- full color video screen for surface pasting; H --- super highlight.No Product code Pixel diameter Pixel spacing point Pixel composition Colour Unit composition Brightness Horizontal perspective one vp20 16.0mm 20.0mm 2500 points / m2 2R4YG Bicolor 48x32 points 4500nit 60 two vp20 19.0mm 22.0mm 2066 points / m2 3R6YG Bicolor 24X32 points * 48x64 4000nit 60 three VP31.25 26.0mm 31.25mm 1024 points / m2 4R12YG Bicolor 24X32 points 4000nit 60 four TP14 12.0mm 14.0mm 5102 points / m2 2R1G1B Full color 48x64 points 6000nit 60 five TP16 14.0mm 16.0mm 3906 points / m2 2R1G1B Full color 48x64 points 6000nit 60 six TP20 16.0mm 20.0mm 2500 points / m2 2R1G1B Full color 48x64 points 5500nit 60 seven TP22 19.0mm 22.0mm 2066 points / m2 2R1G1B Full color 48x64 points 5000nit 60 eight TP22 19.0mm 22.0mm 2066 points / m2 3R2G1B Full color 48x64 points 7400nit 60 nine TP25 22.0mm 25.0mm 1600 points / m2 2R1G1B Full color 24X32 points * 48x64 5500nit 60 ten TP31.25 26.0mm 31.25mm 1024 points / m2 4R2G1B Full color 24X32 points 5000nit 60 Indicator parameters of LED Expressway display screenNo Product code Pixel Spacing Density Pixel composition Colour Unit composition Brightness Horizontal perspective one hwp20 16.0mm 20.0mm 2500 points / m2 2R1G1B2R1G Full colorBicolor 24X32 points 7000nit 45 two hwp20 19.0mm 22.0mm 2066 points / m2 2R1G1B Full color 24X32 points 6500nit 45 Main index parameters of LED graphic screenNo Product code Pixel Spacing Density Pixel composition Colour Unit composition Brightness Horizontal perspective one SE3.7 DF3.7 3.7mm 4.75mm 44444 points / m2 R/1R1G Single / two color 24X48 points24x72 points32x80 points 150/110nit 80 two SF5 5.0mm 7.62mm 17241 points / m2 R Monochrome 16x80 points32x80 points 130nit 80 three SHF5 5.0mm 7.62mm 17241 points / m2 R Monochrome super bright 32x80 points 800nit 80 four SP10 DP10 8.0mm 10.0mm 10000 points / m2 4R2R2YG monochromeBicolor * 2200nit 60 five SP16 DP16 15.0mm 16.0mm 3906 points / m2 4R2R2YG monochromeBicolor * 3400nit 60 Note: the graphic display screen features that one computer can control several screens, which can be networked and displayed offline.Main indicators and parameters of LED indoor video screenNo Product code Pixel Spacing Density Pixel composition Colour Unit composition Brightness Horizontal perspective onetwo VF3 VF3.7 3.0mm3.7mm 4.0mm 62500 points / m2 1R1G Bicolor 64x64 points 160nit 80 4.75mm 44444 points / m2 1R1G Bicolor 32x64 points 120nit 80 three VF5 5.0mm 7.62mm 17241 points / m2 1R1G Bicolor 32x64 points 80nit 80 four VF8 8.0mm 10.0mm 10000 points / m2 1R3YG Bicolor 48x64 points 1900nit 60 five VF10 10.0mm 12.0mm 6944 points / m2 1R3YG Bicolor 48x64 points 2400nit 60 six T**chipF5 5.0mm 7.625mm 17212 points / m2 Table paste 3 in 1 Full color 48x64 points* 3000nit 80 seven TF8 8.0mm 10.0mm 10000 points / m2 2R1G1B Full color 48x64 points* 2500nit 60 eight T**chipF8 8.0mm 10.0mm 10000 points / m2 Table paste 3 in 1 Full color 48x64 points* Riya: 3500nitSiemens: 2200nit 80 nine TF10 10.0mm 12.0mm 6944 points / m2 2R1G1B Full color full color 48x64 points* 2200nit 60 ten T**chipF10 10.0mm 12.0mm 6944 points / m2 Table paste 3 in 1 48x64 points* Riya: 2430nitSiemens: 1530nit 80

LED electronic display screen is composed of tens of thousands - hundreds of thousands of semiconductor LED pixels evenly arranged. LED pixels with different colors can be manufactured by using different materials. At present, the most widely used are red, green and yellow. The development of blue and pure green LEDs has reached the practical stage. LED display screen can display changing numbers, words, graphics and images; It can be used not only in indoor environment, but also in outdoor environment. It has incomparable advantages over projectors, TV walls and LCD screens. The reason why LED has been widely valued and developed rapidly is inseparable from its own advantages. These advantages can be summarized as follows: high brightness, low working voltage, low power consumption, miniaturization, long service life, impact resistance and stable performance. The development prospect of LED is very broad. At present, it is developing towards higher brightness, higher weather resistance, higher luminous density, higher luminous uniformity, reliability and panchromatic.What is led electronic display? LED electronic display screen is composed of tens of thousands - hundreds of thousands of semiconductor LED pixels evenly arranged. LED pixels with different colors can be manufactured by using different materials. At present, the most widely used are red, green and yellow. The development of blue and pure green LEDs has reached the practical stage. LED panel: LED is the abbreviation of light emitting diode, or LED for short.It is a display screen used to display text, graphics, images, animation, market, video, video signals and other information by controlling the display mode of semiconductor light-emitting diodes. LED display screen is divided into graphic display screen and video display screen, both of which are composed of LED matrix blocks. The graphic display screen can display Chinese characters, English text and graphics synchronously with the computer; The video display screen is controlled by microcomputer, with both graphics and images. It can broadcast all kinds of information in real-time, synchronous and clear information transmission mode. It can also display two-dimensional and three-dimensional animation, video, television, VCD programs and live scene.LED display screen has bright colors and strong three-dimensional sense. It is as static as oil painting and as dynamic as film. It is widely used in stations, docks, airports, shopping malls, hospitals, hotels, banks, securities markets, construction markets, auction houses, industrial enterprise management and other public places. LED display screen can display changing numbers, words, graphics and images; It can be used not only in indoor environment, but also in outdoor environment. It has incomparable advantages over projectors, TV walls and LCD screens.The reason why LED has been widely valued and developed rapidly is inseparable from its own advantages. These advantages can be summarized as follows: high brightness, low working voltage, low power consumption, miniaturization, long service life, impact resistance and stable performance. The development prospect of LED is very broad. At present, it is developing towards higher brightness, higher weather resistance, higher luminous density, higher luminous uniformity, reliability and panchromatic. Classification of LED display screen 1. According to the color primary color, it can be divided into single primary color display screen: single color (red or green). Dual primary color display: red and green dual primary colors, 256 gray levels, and can display 65536 colors.Full color display screen: red, green and blue. The full-color display screen with 256 gray levels can display more than 16 million colors. 2. LED digital display screen classified by display device: the display device is a 7-segment code nixie tube, which is suitable for making clock screen, interest rate screen, etc. and displaying digital electronic display screen. LED dot matrix graphic display screen: the display device is a dot matrix display module composed of many evenly arranged light-emitting diodes, which is suitable for playing text and image information. 3. Indoor display screen is classified according to the use occasion: the luminous point is small and general 3mm-- 8mm, the display area is generally several to more than ten square meters. Outdoor display screen: the area is generally tens of square meters to hundreds of square meters, with high brightness, can work in the sun, and has the functions of wind, rain and waterproof. 4. Indoor screen classified by luminous point diameter: 3mm 3.75mm 5mm, outdoor screen: 10mm 12mm 14mm 16mm 18mm 20mm 25mm 31.25mm 36mm. The basic unit of outdoor screen is the light-emitting cylinder.The principle of the light-emitting cylinder is to seal a group of red, green and blue light-emitting diodes in a plastic cylinder to emit light together to enhance brightness. Production process of LED electronic display screen: a) cleaning: use ultrasonic to clean PCB or LED support and dry it. B) mounting: prepare silver glue on the bottom electrode of LED die (large wafer) for expansion, place the expanded die (large wafer) on the spinel table, install the die on the corresponding pad of PCB or LED support one by one with a spinel pen under the microscope, and then sinter to solidify the silver glue. C) pressure welding: connect the electrode to the LED tube core with aluminum wire or gold wire welder to be used as the lead for current injection. Aluminum wire welding machine is generally used for led directly installed on PCB. (gold wire welder is required to make white top-led) d) packaging: the LED tube core and welding wire are protected with epoxy through dispensing.Dispensing on PCB board has strict requirements on the colloid shape after curing, which is directly related to the brightness of the finished backlight. This process will also undertake the task of lighting phosphor (white LED). E) welding: if the backlight adopts smd-led or other encapsulated led, the LED needs to be welded to the PCB before the assembly process. F) film cutting: die cut various diffusion films and reflective films required for backlight with punch. G) assembly: manually install various materials of the backlight source in the correct position according to the drawing requirements. H) test: check whether the photoelectric parameters and light output uniformity of the backlight are good.Main products: 1. P16mm outdoor full-color LED display. 2. P20mm outdoor full-color LED display. 3. P7.62mm indoor patch three to one full-color LED display. 4. P10mm indoor patch three to one full-color LED display. [edit this paragraph] current situation of market prospect of LED electronic display screen: at present, due to the high cost of LED electronic display screen, it is mainly used in relatively high-end places, mainly concentrated in the prosperous places of the city, as a part of multimedia advertising. Single and double color LED electronic display screen is mainly used in transportation, expressway, banking, securities trading and other financial places. Later: LED electronic display adopts low-voltage scanning drive, which has the advantages of low power consumption, long service life, low cost, high brightness, large viewing angle, long visual distance, waterproof, many specifications and varieties. It can meet the needs of various application scenarios. It has a very broad development prospect and is recognized as the LED application market with the most growth potential and the fastest development.In the upcoming 2010 Shanghai World Expo, future large-scale sports events and other new demands will promote the large-scale development of LED display. In addition, the large-scale LED display screens that have been erected will undergo a change of machines every 10 years. With the improvement of people's living standards, outdoor LED display screens will be gradually applied to various industries. It entered the Guangdong market in 1990. At present, there are more than 100000 LED electronic display engineering cases in Guangdong,. At present, it has occupied 98% of the market share of full-color LED electronic display in Guangdong, 200% of large-scale projects of single and dual color LED display, and 120% of the wholesale share of LED electronic display modules. With a strong R & D team, excellent quality control, perfect sales network system and humanized after-sales service, a perfect Mingpu technology brand image has been established in the eyes of the majority of LED electronic display screen users and LED electronic display screen dealers.

LED electronic display screen is composed of tens of thousands to hundreds of thousands of semiconductor LED pixels evenly arranged. LED pixels with different colors can be manufactured by using different materials. At present, the most widely used are red, green and yellow. The development of blue and pure green LEDs has reached the practical stage.1. Area ductility, LED electronic display screen can be extended arbitrarily, and seamless splicing is realized.2. Compared with the LCD screen, the brightness of the LED screen will not fade with the extension of time, and the primary color will always be maintained.3. The luminous brightness is strong. When the sun shines directly on the screen surface within the visual distance, the display content is clearly visible. The super gray level control has 1024-4096 gray level control, and the display color is more than 16.7M, with clear and realistic color and strong three-dimensional sense.4. Static scanning technology adopts static latch scanning mode and high-power drive to fully ensure luminous brightness.5. Automatic brightness adjustment, with automatic brightness adjustment function, can obtain the best playback effect in different brightness environments. In terms of display effect, the high brightness, wide viewing angle and good color restoration ability of LED electronic display screen are also better than LCD screen.6. Imported large-scale integrated circuits are fully adopted, which greatly improves the reliability and is convenient for debugging and maintenance.7. Advanced digital video processing technology, distributed scanning, BSV liquid crystal splicing technology, high-definition display, modular design / constant current static drive, automatic brightness adjustment, ultra bright pure color pixels, clear image, no jitter and ghosting, and eliminate distortion. Video, animation, charts, text, pictures and other information display, online display and remote control.The above is a brief introduction about what led electronic display is. LED electronic display can be used not only in indoor environment, but also in outdoor environment. It has incomparable advantages over projector, TV wall and LCD. The reason why LED has been widely valued and developed rapidly is inseparable from its own advantages. These advantages can be summarized as follows: high brightness, low working voltage, low power consumption, miniaturization, long service life, impact resistance and stable performance.The development prospect of LED is very broad. At present, it is developing towards higher brightness, higher weather resistance, higher luminous density, higher luminous uniformity, reliability and panchromatic.fqj

To judge the problem, we must first deal with the primary and then the secondary, deal with the obvious and serious problems first, and deal with the small problems later. Short circuit shall be the highest priority.1. Resistance detection method: adjust the multimeter to the resistance gear to detect the ground resistance value of a certain point of a normal circuit board, and then detect the same point of another same circuit board to test whether the resistance value is different from the normal resistance value. If it is different, the scope of the problem is determined.2. Voltage detection method, adjust the multimeter to the voltage level, detect the ground voltage at a point of the suspected circuit, and compare whether it is similar to the normal value, otherwise the range of the problem is determined.3. Short circuit detection method: adjust the multimeter to the short circuit detection gear (some are diode voltage drop gear or resistance gear, which generally has alarm function) to detect whether there is a short circuit. If a short circuit is found, it shall be solved first so that it will not burn other devices. This method must be operated when the circuit is powered off to avoid damaging the meter.4. Voltage drop detection method: adjust the multimeter to the diode voltage drop detection gear. Because all ICs are composed of many basic single components, they are only miniaturized. Therefore, when a current passes through a pin, there will be a voltage drop on the pin. Generally, the voltage drop on the same pin of an IC of the same model is similar. According to the voltage drop on the pin, it must be operated when the circuit is powered off. This method has some limitations. For example, if the detected device is high resistance, it can not be detected. 4 Handling steps for common problems of unit board unit board failure:A. The whole board is not bright1. Check whether the power supply is connected to the signal line.2. Check whether the test card can identify the interface. If the red light of the test card flashes, it will not be identified. Check whether the lamp board is connected with the power supply and ground of the test card, or there is a short circuit between the signal and ground of the lamp board interface, so that the interface cannot be identified. (smart test card)3. Detect whether 74hc245 has faulty welding or short circuit, and whether the corresponding enable (EN) signal input and output pin on 245 has faulty welding or short circuit to other lines. Note: mainly check the power supply and enable (EN) signal.B. During oblique scanning, regular interlaced lines are not lit, and the display screen overlaps1. Check whether there is broken wire, faulty welding or short circuit between a, B, C and D signal input ports and 245.2. Check whether there is open circuit, faulty welding or short circuit between output terminals a, B, C and d corresponding to 245 and 138.3. Detect whether there is a short circuit between signals a, B, C and D or whether a signal is short circuited to ground. Note: it mainly detects ABCD line signal.C. When fully lit, one or more lines are not lit1. Detect whether the line between 138 and 4953 is open circuit, faulty welding or short circuit.D. During line scanning, two or more lines (generally multiple of 2, regular) are lit at the same time1. Check whether there is a short circuit between signals a, B, C and D.2. Check whether the 4953 output terminal is short circuited with other output terminals.E. Single or multiple points (irregular) do not light up when fully lit1. Find the control pin corresponding to the module and measure whether it is short circuited to the line.2. Replace the module or single lamp.F. When fully lit, one or more columns are not lit1. Find the pin controlling this column on the module and test whether it is connected to the output of the drive IC (74HC595 / TB62726).G. There is single point or single column highlight, or whole row highlight, and it is not controlled1. Check whether the column is short circuited to power and ground.2. Check whether the line is short circuited to the positive pole of the power supply.3. Replace its drive IC.H. The display is confused, but the signal output to the next board is normal1. Detect whether the corresponding STB latch output terminal of 245 is connected with the latch terminal of the drive IC or whether the signal is short circuited to other lines.1. The display is confused and the output is abnormal1. Detect whether the clock CLK latch STB signal is short circuited.2. Detect whether the clock CLK of 245 has input and output.3. Check whether the clock signal is short circuited to other lines.Note: it mainly detects clock and latch signals.J. Display out of color1. Detect whether the data terminal of the color of 245 has input and output.2. Detect whether the data signal of this color is short circuited to other lines.3. Check whether there is open circuit, short circuit and faulty soldering at the cascade data port between the driving IC of this color. Note: it is easy to find the problem by using the voltage detection method. Check whether the voltage of the data port is different from the normal one to determine the fault area.K. There is a problem with the output1. Check whether the line from the output interface to the signal output IC is connected or short circuited.2. Check whether the clock latch signal of the output port is normal.3. Check whether the cascade output data port between the last drive IC is connected with the data port of the output interface or short circuited.4. Whether the output signals are short circuited to each other or to the ground.

The first is high light efficiency: the light efficiency of LED electronic display screen can be said to be an important indicator of energy-saving effect. At present, China needs to strengthen the light efficiency effect. To really achieve high light efficiency, we should solve relevant technical problems from all links of the industrial chain, so how to achieve high light efficiency? This paper will discuss the technical problems to be solved in epitaxy, chip, packaging, lamps and other links.1. Improve internal quantum efficiency and external quantum efficiency.2. Improve the light output efficiency and reduce the junction temperature.3. Improve the lighting efficiency of lamps.Secondly, from the perspective of high color rendering: there are many light and color quality of LED electronic display screen, including color temperature, color rendering, light and color fidelity, light and color naturalness, tone recognition, visual comfort and so on. Here, we only discuss how to solve the problems of color temperature and color rendering. Making high color rendering LED display light source will lose more light efficiency, so these two factors should be taken into account in the design. Of course, the combination of RGB three primary colors must be considered to improve the high color rendering. Here, I also have three methods:1. Multicolor phosphor.2. RGB multi chip combination.3. Phosphor and chip.Thirdly, in terms of high reliability, it mainly includes failure rate, service life and other indicators. However, there are different understandings and explanations in application. High reliability refers to the ability of products to complete specified functions under specified conditions and within specified time. Led failure mainly includes serious failure and parameter failure. Life is the characteristic value of product reliability Generally refers to the statistical average. For a large number of components, the life of LED devices is the meaning of this description. However, the factors affecting the reliability of LED display products include chip manufacturing, packaging, thermal resistance, heat dissipation and so on. Now that we are talking about this, we hope that enterprises will make two requirements for LED display products on the basis of total quality control:1. Reduce failure rate.2. Prolong the wear and tear failure time.The last is to reduce the product cost: at present, many consumers feel that the price is too high when purchasing LED display screen. Therefore, many LED display screen entrepreneurs have also taken corresponding measures to reduce the cost. In addition to mass production, they mainly take technical measures to reduce the cost. It is mainly to reduce the cost in epitaxial chip, packaging, driving and heat dissipation, so as to fundamentally solve the cost problem of LED display products. Specifically, it is discussed from the following four aspects:1. Method for reducing cost of epitaxial chip link.2. Methods to reduce the cost of packaging.3. Methods to reduce the cost of lamps.4. Reduction of other supporting costs

With the popularity of intelligent products, LED electronic display screen is more and more widely used. Let's have a simple understanding of LED electronic display, but what about a deeper understanding? Do you know the five hidden misunderstandings of LED electronic display? If you don't know, just look down!, do you know1 LED electronic display software is not freeAt present, only a few enterprises have genuine software. It is illegal to use piracy now.2 Point by point correction does not require the use of a dedicated driver chipAs long as the control system supports, the general driver chip can also realize point by point correction!3 Chromaticity correction is not equal to chromaticity uniformity correction. The application of chromaticity correction is more the conversion of color gamut space. Under normal circumstances, after brightness correction, the bright color uniformity of the display screen can reach a very high level. Combined with color gamut space correction, the color fidelity of the display screen can also reach a very high level. Here are chromaticity correction and chromaticity uniformity correction:1. Chromaticity correction: meet customers' special requirements for display gamut space: correct the display gamut space to the color space specified by customers. Improve the color fidelity of the display screen and make the color restore more realistic: correct the color gamut space of the display screen to standard color spaces such as sRGB and NTSC.2. Chromaticity uniformity correction: due to the good color separation accuracy and stability of the color splitter and the effective process flow of mixing lamps and crystals, the application occasions of chromaticity uniformity correction are quite limited. When cleaning the inventory, we must mix a very small amount of lamps with scattered wavelengths on one screen. At this time, chromaticity uniformity correction is also the only choice. Due to mistakes in the production process, lamps / chips of different wavelengths are mixed together and used on the same screen. Chromaticity uniformity correction can be used as a final remedy.4 The point by point correction is not done by the control system manufacturer, and the correction technology is not bundled with the control system. The real necessary conditions for point by point correction are:1. A control system that can realize point by point correction.2. High precision and high efficiency light spot brightness acquisition equipment. Conclusion: the point by point drive control has long been realized, and the general control systems in the market already have this function. However, for the acquisition of millions of light point data, some control system manufacturers have developed various tools, which are incompatible with other systems. This leads to the misunderstanding that the point by point correction and control system are bundled and integrated.5 Gray level of LED electronic display screenAs a dual primary color and full-color display screen, gray level is an important index. At present, the market is full of many 16 and 64 gray display screens pretending to be 256 gray. Its control cost is only 1 / 5 of that of 256 gray levels. The simple way is to play a VCD of a more intense sports scene and check whether it can be seen clearly on the LED electronic display screen.

LED display is not easy to assemble, just like an assembled computer. Even led electronic display is more chaotic and more focused on technology. It is connected by many modules, and the module is assembled by many lamp beads. At the same time, this process is a ring, and then a ring. Be careful inside, otherwise it will affect the electronic display function of LED.And the LED display is very important in the connection. Once the connection is not good, the next link will not be normal operation. Only knowing these knowledge, the LED display screen will be safer and better. Because its high brightness LED display screen is also related to power, the cost of single packaging of high-power and high brightness LED is high, and the power of single high brightness LED display screen is very small. Therefore, multiple LED displays must be arranged together according to the requirements. On the one hand, it can meet the use requirements of large range, high brightness, dynamic display, color change and so on, on the other hand, it can meet the matching requirements of LED drivers.There are four ways to connect the LED electronic display:First, the whole series of methods: Generally speaking, the ends of LED 1 - N and series connection method are the same, and the current of LED display is the same. The other is an improved method of connecting the bypass to 1.1.Secondly, the whole parallel method: one is the abbreviated parallel method, the other is the independent matching method. In the simplified parallel method, led1-n is connected in parallel, and the voltage of each LED is equal in operation. The reliability is not high, but for the parallel method, the independent matching is adopted on this problem, which has a good driving effect. Under good conditions, the single LED display is maintained, the problem will not affect other tasks, and the matching is quite different.Thirdly, the hybrid method is introduced, and the advantages of parallel and series are summarized. There are also two. One is the first string, then the hybrid method, and the other is the first string and the second string.Fourth, insert array method: insert array is the first method to improve the reliability of LED display operation, and puts forward the defect rate.

We often see the gray sky in the morning. In fact, it is shrouded by something called haze. It is estimated that many people do not know what is haze. Its main components are formed by the mixture of sulfur dioxide, nitrogen oxides and inhalable particles. The first two are gaseous pollutants, which combine with fog to make the sky gray in an instant. In fact, fog is a non-toxic and harmless natural phenomenon, and the formation of haze is mainly the result of a large number of suspended particles in the air and meteorological conditions. Fog and haze are often accompanied, and fog and haze occur at the same time. Conditions such as water vapor, calm wind, inversion and condensation core are indispensable.Toxic components in haze not only seriously endanger people's health, but also have a great impact on the operation of outdoor LED electronic display screen. In fact, we can divide haze into fog and haze, because their main hazards to the display screen are different:01Harm of fog to outdoor display screenFog is formed by condensation of water vapor in the air. In other words, the humidity in the air is relatively large, which will cause the LED display screen to be wet. Excessive humidity will cause the PCB board, power supply, power cord and other devices of the display screen to be easily oxidized and corroded, and even short circuit, resulting in failure.02Harm of haze to outdoor display screenHaze is the aggregate of suspended dust and various small particles in the air, in which the dust particles suspended in the air are the core material of haze. Under the influence of haze for a long time, all kinds of fine dust in the air will enter the equipment through the ventilation hole, which will accelerate the wear and even damage of fans and other equipment, and the dust will fall on the surface of internal control devices of the display screen, which will not only reduce the heat dissipation and insulation performance of the display screen, but also accelerate the aging of the display screen and affect the normal service life.Then, how to make the display stand the test in the haze weather for a long time requires users and engineers to pay more attention when purchasing and maintaining:1. First of all, users must see whether the display screen meets the dust-proof level required by the use environment during the procurement process. In terms of dust prevention, the international standard is ip0x-ip6x, which is a design grade to prevent foreign matter intrusion. If it is installed in the northern area with more dust and haze weather, its front and back protection grade must reach IP65, that is, it must adopt a complete dust-proof structure, that is, it is closed in the state of water spraying.2. Be sure to pay attention to whether the PCB of LED display screen has been subject to anti-corrosion treatment, such as three anti-corrosion paint on the surface; Whether the power supply and power cord are high-quality accessories; And check whether the welding part of the screen body that is most likely to be corroded has been treated with rust prevention.3. During daily maintenance, dust must be removed regularly to avoid short circuit caused by dust absorbing moisture in the air in wet weather and mildew of PCB board and electronic components.

I. service life of 100000 hoursThe technical data issued by the LED material manufacturer shows that the service life of the LED illuminant is 10000 hours under the ideal state. The ideal state refers to the time from light to no light under the constant voltage and constant current state in the laboratory, and 10000 hours is equivalent to 11 years. The amount of water in a barrel is determined by the lowest wooden board. At present, the LED display screen is a civil product level device with a service life of no more than 8 years. The function of the display screen is to watch. When the display screen is on and can be seen clearly only at night, it cannot be said that it is qualified and valuable. A car can be driven for 15 years. If it is idle for 3 years, it will be scrapped. The environment and method used have a great impact on the service life of the product.2 Comply with the national standard, the general specification of LED display screen is the ministerial standard in 1995. So far, many companies claim to meet the national standards. If we look at the standards at that time after 8 years of scientific and technological development, it is no longer the standard. For example, at the point of out of control, the national standard is 3 / 10000 3.75 indoor dual primary color display screen as an example. Generally, the display screen with 640x480 standard resolution is 7 square meters, with 43264 points per square meter. According to the national standard, there can be 90 out of control points. Who will pay for such a display today.3 There is a common problem of Chinese enterprises in the software free display industry - only production without R & D. At present, only a few enterprises have genuine software. It is illegal to use piracy now.4 The low price depends on the performance price ratio rather than the price.5 As the gray level of dual primary color and full-color display screen, gray level is an important index. At present, the market is full of many 16 and 64 gray display screens pretending to be 256 gray. Its control cost is only 1 / 5 of that of 256 gray levels. The simplest way is to play a VCD of a more intense sports scene and check whether it can be seen clearly on the LED display screen.6 If you want to buy, you need the bestAll purchasing power comes from needs, meets needs and has a certain advance. Blind pursuit will waste a lot of money to buy functions you don't need.The above materials tell a very thorough analysis of the current LED products purchased by ordinary users, not only for LED electronic displays, but also for LED lamps http://ledlights.net.cn In fact, the same can be referred to.

As a media of publicity, LED display screen appears frequently in our life, and the demand for maintenance identification materials relative to LED electronic display screen is also increasing. Let's discuss how to identify the brightness of LED electronic display screen.First, let's understand what is the brightness of LED electronic display:The brightness of LED light-emitting tube refers to the intensity of light emitted by the light-emitting body, which is called light intensity and expressed by MCD. The luminous brightness of LED screen is a comprehensive index, which refers to the comprehensive index of the total luminous amount (luminous flux) of all LED modules in unit volume and the illuminance at a certain distance.Brightness of LED display screen: the unit of luminous intensity brightness per unit area in a given direction is CD / m2.The brightness is directly proportional to the number of LEDs per unit area and the brightness of the LED itself. The brightness of LED is directly proportional to its driving current, but the service life is inversely proportional to the square of its current, so the driving current cannot be excessively increased in order to pursue brightness. Under the same point density, the brightness of LED display screen depends on the material, packaging form and size of LED chip. The larger the chip, the higher the brightness; Conversely, the lower the brightness.So what are the brightness requirements for the screen body?General brightness requirements are as follows:(1) Indoor LED display: 800cd / m2(2) Semi indoor LED display screen: 2000cd / m2(3) Outdoor LED display (south facing north): 4000cd / m2(4) Outdoor LED display (facing south): 8000CD / m2The quality of LED light-emitting tubes sold in the market is uneven, and most of the brightness can not be guaranteed. The phenomenon of shoddy goods deceives consumers. Most people do not have the ability to identify the brightness of LED light-emitting tubes. Therefore, businesses say that the brightness is the brightness. And it is difficult to distinguish with the naked eye, so how to identify it?1 How to identify the brightness of LED electronic display screen1. Make a 3V DC power supply convenient for connecting light-emitting diodes, preferably made of batteries. Two button batteries can be used, which are installed in a small plastic tube and lead out two probes as positive and negative output. The tail end is directly made into a switch with shrapnel. When in use, the positive and negative probes correspondingly contact the positive and negative pins of the LED, press and hold the switch at the tail end, and the LED is powered on.2. Secondly, a simple light measuring device is composed of a photoresist and a digital multimeter. Two thin wires are led out of the photoresist and directly connected to the two probes of the digital multimeter. The gear of the multimeter is placed at 20K (depending on the photoresist, try to make the reading accurate). Note that the measured value is actually the resistance of the photoresist. Therefore, the brighter the light is, the smaller the value is.3. Take an LED and light it with more than 3V DC. The light emitting head is facing and close to the photosensitive surface of the connected photosensitive resistor. At this time, the multimeter will read to distinguish the luminous brightness of the LED.2 Brightness discrimination level refers to the brightness level between the darkest and whitest images that can be distinguished by human eyes.The gray level of LED electronic display screen is very high, which can reach 256 or even 1024. However, due to the limited sensitivity of human eyes to brightness, these gray levels can not be fully recognized. In other words, many people with adjacent gray levels may look the same. And eye discrimination varies from person to person. For the display screen, the more the human eye recognition level, the better, because the displayed image is for people to see after all. The more brightness levels that human eyes can distinguish, the larger the color space of the display screen, and the greater the potential to display rich colors. The brightness identification level can be tested with special software. Generally, the display screen can reach more than level 20, which is a better level.3 Requirements for brightness and visual angle:The brightness of the indoor full-color LED display screen should be more than 800cd / m2, and the brightness of the outdoor full-color display screen should be more than 1500cd / m2 to ensure the normal operation of the display screen, otherwise the displayed image will not be seen clearly because the brightness is too low. The brightness is mainly determined by the quality of LED die. The size of the visual angle directly determines the audience of the LED display screen, so the larger the better. The viewing angle is mainly determined by the die package.It is very necessary to determine the brightness of LED electronic display screen. At present, the brightness requirements of urban bright LED display screen, or new regulations are issued. If the brightness of LED screen is too high, it will cause trouble to nearby residents. In order to avoid adverse reactions, businesses need to have relevant professional knowledge when customizing and maintaining LED displays.The above is about how to identify the real brightness index brightness of LED electronic display screen. I hope it will help you. In addition, the brightness of LED display screen is not the bigger the better, but the appropriate brightness will achieve unexpected results according to the use demand.