led lamp beads

As we all know, LED lamp beads are light-emitting diodes, LED lamp beads are widely used in lighting, LED large screen display, traffic lights, decoration, computers, electronic toys gifts, switches, telephones, advertising, urban luster project and many other production fields. 

LED lamp beads as LED electronic display production of the highest, the largest amount of components. LED electronic display quality impact plays a leading role in the LED lamp beads, today to introduce why LED lamp beads is the most critical components of LED electronic display, how to identify the merits of LED lamp beads?

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The most critical component of the full-color LED electronic display is the LED lamp beads. There are three reasons for this.

First, the LED full-color screen is the most critical device used in the whole machine, and each square meter will use thousands to tens of thousands of LED beads; 

Second, LED lamp beads determine the main body of the whole screen optical display performance, directly affecting the audience's evaluation of the display;

Third, the largest proportion of the overall cost of LED electronic display, ranging from 30% to 70%.

How to identify the advantages and disadvantages of LED electronic display lamp beads

First, look at the solder joints. Legitimate LED lamp bead manufacturers produce LED lamp beads are SMT SMD process, with solder paste and reflow soldering process production 

Second, look at the quality of FPC, FPC copper and calendering copper two, copper foil is convex copper board, if you look closely, you can see from the pad and FPC connection 

Third, look at the cleanliness of the surface of the LED beads. If the use of SMT process production of LED beads, the surface cleanliness is very good, see what impurities and stains

Fourth, look at the LED lamp with the chip and production process, the eye is not to see the difference between aging equipment and testing equipment if you put several manufacturers of LED on the aging instrument with high current aging 24 hours or longer, and then go to measure the brightness of several manufacturers of LED, to see that the led luminous intensity attenuation minimum, attenuation minimum that the quality is the best.

What is the impact of LED lamp beads on the LED display 

Perspective The perspective of the LED electronic display is determined by the perspective of the LED lamp beads. At present, most of the outdoor electronic display selected horizontal perspective 120 °; vertical perspective 50 °; elliptical LED indoor electronic display is selected horizontal and vertical are 120 °; electronic display on the highway due to its special nature of the general choice of 30 °; perspective of the round LED is enough, some of the high building electronic display on the vertical perspective requirements are higher. Angle of view and brightness contradict each other, large perspective will certainly reduce the brightness. The angle of view needs to be selected according to the specific use to decide. 

2. brightness LED brightness is an important determinant of electronic display brightness. the higher the brightness of the LED, the greater the margin of the use of current, to save power consumption, adhere to the LED stability is good. the LED has different angle values, the chip brightness has been set, the smaller the angle, the LED is brighter, but the display angle is smaller. Generally should choose 120 degrees of LED to ensure that the display sufficient perspective. For different point pitch and different view distance of the electronic display, should find a balance point in brightness, angle and price. 

3.Failure rate As the full-color electronic display is composed of tens of thousands or even hundreds of thousands of groups of red, green and blue LED pixels, any color LED failure will affect the overall visual effect of the electronic display. Generally speaking, according to industry experience, LED electronic display assembly to aging 72 hours before shipment failure rate should not be higher than three ten thousandths (refers to the LED lamp bead failure caused by its own reasons) 

4. anti-static ability LED semiconductor devices, sensitive to static electricity, very easy to cause static failure, so the anti-static ability of the display life is critical. In general, the LED human electrostatic mode test failure voltage should not be less than 2000V 

Life The theoretical life of LED lamp beads is 100,000 hours, which is much longer than the working life of other parts of LED electronic display, so as long as the LED lamp beads quality assurance, suitable working current, PCB heat dissipation design is reasonable, electronic display production process is rigorous, LED lamp beads will be one of the most durable parts of the display machine. LED lamp beads account for 70% of the price of LED electronic display, so that LED lamp beads can determine the quality of LED electronic display. Our country is the production of LED lamp beads, is also the gathering place of LED electronic display production. LED electronic display high technology requirements is the future development trend, LED electronic display high quality requirements, not only about the LED electronic display manufacturers towards, also implicated in the development of LED electronic display device manufacturers. From LED lamp beads gate-keeping, to promote China's LED electronic display manufacturing power to LED electronic display manufacturing power change. 

6. attenuation characteristics LED electronic display will appear after a long period of work brightness decline and display color inconsistency phenomenon, mainly due to the brightness of LED devices caused by the attenuation of LED brightness will cause the display screen brightness reduction. Red, green, blue LED brightness attenuation amplitude inconsistency will cause the LED display color inconsistency, is often said to display the phenomenon of flowers. High-quality LED devices can well control the brightness decay amplitude. According to 1000 hours of room temperature light 20mA specification, red attenuation should be less than 2% blue, green attenuation should be less than 10% so blue, green LED electronic display design try not to use 20mA current, it is best to use only 70% to 80% of the rated current. Attenuation characteristics in addition to red, green, blue LED characteristics related to their own, the use of current, PCB board thermal design, the use of the display environment temperature, etc. have an impact on the attenuation. 

7.Size The size of LED beads affects the pixel distance of LED electronic display, i.e. resolution. 3535 type SMD LED is mainly used for P10/P8/P6 indoor display, 2121 type SMD LED is mainly used for P2/P2.5/P3 indoor display. Under the premise of unchanged point spacing, LED bead size increases, can increase the display area, reduce the sense of granularity, but due to the reduction of the black area, will reduce the contrast; on the contrary, the LED size decreases, reducing the display area, the sense of granularity increases, the black area increases, increasing the contrast. 

8. Consistency full-color electronic display is composed of countless red, green, blue LED pixels spell each color LED brightness, wavelength consistency determines the brightness consistency, white balance consistency, chromaticity consistency of the entire display. Generally speaking, display manufacturers require device suppliers to provide 5nm wavelength range and 11.3 brightness range of LEDs these indicators can be graded by the device supplier through the spectrophotometric color separation machine to achieve the consistency of voltage generally do not require. Because the LED has an angle so full-color LED electronic display also has the angle directional, that is, when viewed at different angles, its brightness will be increasing or decreasing so that red, green, blue three colors LED angle consistency will seriously affect the consistency of the white balance at different angles, directly affecting the display video color fidelity. To do red, green, blue three LEDs at different angles when the brightness changes match the consistency, the need for strict scientific design in the package lens design, the choice of raw materials, which depends on the technical level of the package supplier. Normal direction white balance and good display, if the LED angle consistency is not good, the white balance effect of the whole screen at different angles will be bad LED lamp beads angle consistency characteristics can be measured by the LED angle integrated tester, especially important for medium and high-grade display.