What is the impact of LED beads on LED display screen
What is the impact of LED beads on LED display screen
LED beads as the highest cost LED display, the largest amount of components, for the LED display quality impact plays a leading role. Today LED Controller for you to introduce why LED beads are the most critical components of LED display, how to identify the advantages and disadvantages of LED beads?
The most critical component of full color LED display is LED bead. There are three reasons:
First, the LED is the key device with the largest number of full color screen whole machine, each square meter will use thousands to tens of thousands of LEDs;.
Secondly, LED is the main body to determine the optical display performance of the whole screen, which directly affects the audience's evaluation of the display.
Third, LED in the display of the overall cost of the largest proportion, from 30% to 70%.
How to identify the advantages and disadvantages of LED display beads
First, look at the solder joints. Formal LED light strip manufacturers produce LED light strip is the use of SMT SMD process, with solder paste and reflow soldering process production
Second, look at the quality of FPC, FPC copper and calendered copper two kinds of copper, copper foil is convex out of the copper plate, if you look closely, you can see from the pad and the FPC connection!
Third, look at the surface of the LED strip light cleanliness. If the SMT process is used to produce the LED strip, its surface cleanliness is very good, can not see what impurities and stains!
Fourth, look at the LED lights with the chip and production process, with the eyes can not see the difference, to use the aging equipment and testing equipment if you put a few manufacturers of LED on the aging instrument with high current aging for 24 hours or longer, you then go to measure the brightness of a few manufacturers of LEDs to see that the led luminous intensity of the smallest attenuation, the smallest attenuation of the quality of the best.
LED beads on the LED display what are the effects of
1, viewing angle
The angle of view of the LED display is determined by the angle of view of the LED lamp beads. At present, most of the outdoor display choose horizontal viewing angle 100 °;, vertical viewing angle of 50 °; elliptic LED, indoor display choose horizontal and vertical are 120 °; SMD LED. highway display due to its special general selection of 30 °; angle of view of the round LED is enough. Some of the upper floors of the display on the vertical viewing angle requirements are higher. Viewing angle and brightness are contradictory, large viewing angle will inevitably reduce the brightness. Viewing angle selection needs to be based on the specific use to decide.
2, brightness
LED brightness is an important determinant of the brightness of the display. the higher the LED brightness, the greater the margin of the use of current, to save power consumption, to maintain the stability of the LED has the advantage of a different angle value, in the case of the chip brightness has been determined, the smaller the angle, the brighter the LED, but the display of the angle of view is the smaller. Generally should choose 100 degrees of LED to ensure that the display sufficient viewing angle. For different point spacing and different visual distance of the display, should be in the brightness, angle and price to find a balance.
3, failure rate
As the LED full-color display by tens of thousands or even hundreds of thousands of groups of red, green, blue LED pixels composed of three kinds of points, the failure of any color LED will affect the overall visual effect of the display. Generally speaking, according to industry experience, in the LED display began to assemble to aging 72 hours before shipment of failure rate should not be higher than three ten thousandths of a percent (refers to the LED lamp beads itself caused by the failure).
4, anti-static ability
LED is a semiconductor device, sensitive to static electricity, very easy to cause electrostatic failure, so the anti-static ability is crucial to the life of the display. Generally speaking, the LED human body electrostatic mode test failure voltage should not be less than 2000V.
5, life
The theoretical life of the LED device is 100,000 hours, much larger than the working life of other parts of the LED display, so long as the LED device quality assurance, the right working current, PCB heat dissipation design is reasonable, display production process is rigorous, the LED device will be one of the most durable components in the display machine.
LED device accounted for 70% of the proportion of the price of LED display, so that LED device can decide the quality of LED display. China is a big country of LED device production, also is the gathering place of LED display making. high technology requirement of LED display is the future development trend, high quality requirement of LED display, not only about the direction of LED display manufacturers, also implicated in the development of LED display device manufacturers. From the LED device gatekeeper, to promote China's transformation from LED display manufacturing power to LED display manufacturing power.
6, attenuation characteristics
LED display after a long time work will appear brightness decline and display color inconsistent phenomenon, mainly due to the brightness of the LED device attenuation caused by the LED brightness attenuation will cause the display screen brightness reduction. Red, green, blue LED brightness attenuation amplitude inconsistency will cause the LED display color inconsistency, that is, we often say that the display took the phenomenon. High-quality LED devices can well control the brightness attenuation. According to 1000 hours at room temperature light 20mA standard, red attenuation should be less than 2%, blue, green attenuation should be less than 10%, so blue, green LED in the 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 the characteristics of red, green, blue LED itself, the use of current, PCB board thermal design, display the use of ambient temperature and so on have an impact on the attenuation.
7, size
The size of the LED device affects the pixel distance of the LED display, that is, the resolution. 5mm ellipsoidal lamps are mainly used for outdoor displays above P16, 3mm ellipsoidal lamps are mainly used for P12.5, P12, P10 outdoor displays, 3528 chip LEDs are mainly used for indoor displays in P6, P8, 2020 chip LEDs are mainly used for indoor displays such as P2, P3. display screen. Under the premise of the same pitch, the LED device size increases, can increase the display area, reduce the sense of particles, but due to the reduction of the black area, will reduce the contrast; on the contrary, the LED size is reduced, reducing the display area, particles increase, the black area increases, increasing the contrast.
8, consistency
Full-color display is composed of countless red, green, blue LED pixels spelled out, the brightness of each color LED, wavelength consistency determines the brightness of the entire display consistency, white balance consistency, chromaticity consistency. Generally speaking, display manufacturers require device suppliers to provide 5nm wavelength range and 1:1.3 brightness range of the LED, these indicators can be graded by the device supplier through the spectrophotometric color separation machine to achieve. Voltage consistency is generally not required.
As the LED is angled, so the LED full-color display also has the angle directionality, that is, when viewed at different angles, its brightness is incremental or decremental. In this way, red, green, blue three colors LED angle consistency will seriously affect the consistency of the white balance of different angles, directly affecting the fidelity of the display video color. To achieve the red, green, blue three kinds of LED in different angles when the brightness changes to match the consistency of the need for strict scientific design in the package lens design, the original material selection, which depends on the technical level of the packaging supplier. Normal direction white balance and then good display, if the angle of the LED consistency is not good, the whole screen at different angles of the white balance effect will be bad.LED lamp beads of the angle consistency characteristics can be measured by the LED Angle Comprehensive Tester, for the medium and high-grade displays is particularly important.
The most critical component of full color LED display is LED bead. There are three reasons:
First, the LED is the key device with the largest number of full color screen whole machine, each square meter will use thousands to tens of thousands of LEDs;.
Secondly, LED is the main body to determine the optical display performance of the whole screen, which directly affects the audience's evaluation of the display.
Third, LED in the display of the overall cost of the largest proportion, from 30% to 70%.
How to identify the advantages and disadvantages of LED display beads
First, look at the solder joints. Formal LED light strip manufacturers produce LED light strip is the use of SMT SMD process, with solder paste and reflow soldering process production
Second, look at the quality of FPC, FPC copper and calendered copper two kinds of copper, copper foil is convex out of the copper plate, if you look closely, you can see from the pad and the FPC connection!
Third, look at the surface of the LED strip light cleanliness. If the SMT process is used to produce the LED strip, its surface cleanliness is very good, can not see what impurities and stains!
Fourth, look at the LED lights with the chip and production process, with the eyes can not see the difference, to use the aging equipment and testing equipment if you put a few manufacturers of LED on the aging instrument with high current aging for 24 hours or longer, you then go to measure the brightness of a few manufacturers of LEDs to see that the led luminous intensity of the smallest attenuation, the smallest attenuation of the quality of the best.
LED beads on the LED display what are the effects of
1, viewing angle
The angle of view of the LED display is determined by the angle of view of the LED lamp beads. At present, most of the outdoor display choose horizontal viewing angle 100 °;, vertical viewing angle of 50 °; elliptic LED, indoor display choose horizontal and vertical are 120 °; SMD LED. highway display due to its special general selection of 30 °; angle of view of the round LED is enough. Some of the upper floors of the display on the vertical viewing angle requirements are higher. Viewing angle and brightness are contradictory, large viewing angle will inevitably reduce the brightness. Viewing angle selection needs to be based on the specific use to decide.
2, brightness
LED brightness is an important determinant of the brightness of the display. the higher the LED brightness, the greater the margin of the use of current, to save power consumption, to maintain the stability of the LED has the advantage of a different angle value, in the case of the chip brightness has been determined, the smaller the angle, the brighter the LED, but the display of the angle of view is the smaller. Generally should choose 100 degrees of LED to ensure that the display sufficient viewing angle. For different point spacing and different visual distance of the display, should be in the brightness, angle and price to find a balance.
3, failure rate
As the LED full-color display by tens of thousands or even hundreds of thousands of groups of red, green, blue LED pixels composed of three kinds of points, the failure of any color LED will affect the overall visual effect of the display. Generally speaking, according to industry experience, in the LED display began to assemble to aging 72 hours before shipment of failure rate should not be higher than three ten thousandths of a percent (refers to the LED lamp beads itself caused by the failure).
4, anti-static ability
LED is a semiconductor device, sensitive to static electricity, very easy to cause electrostatic failure, so the anti-static ability is crucial to the life of the display. Generally speaking, the LED human body electrostatic mode test failure voltage should not be less than 2000V.
5, life
The theoretical life of the LED device is 100,000 hours, much larger than the working life of other parts of the LED display, so long as the LED device quality assurance, the right working current, PCB heat dissipation design is reasonable, display production process is rigorous, the LED device will be one of the most durable components in the display machine.
LED device accounted for 70% of the proportion of the price of LED display, so that LED device can decide the quality of LED display. China is a big country of LED device production, also is the gathering place of LED display making. high technology requirement of LED display is the future development trend, high quality requirement of LED display, not only about the direction of LED display manufacturers, also implicated in the development of LED display device manufacturers. From the LED device gatekeeper, to promote China's transformation from LED display manufacturing power to LED display manufacturing power.
6, attenuation characteristics
LED display after a long time work will appear brightness decline and display color inconsistent phenomenon, mainly due to the brightness of the LED device attenuation caused by the LED brightness attenuation will cause the display screen brightness reduction. Red, green, blue LED brightness attenuation amplitude inconsistency will cause the LED display color inconsistency, that is, we often say that the display took the phenomenon. High-quality LED devices can well control the brightness attenuation. According to 1000 hours at room temperature light 20mA standard, red attenuation should be less than 2%, blue, green attenuation should be less than 10%, so blue, green LED in the 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 the characteristics of red, green, blue LED itself, the use of current, PCB board thermal design, display the use of ambient temperature and so on have an impact on the attenuation.
7, size
The size of the LED device affects the pixel distance of the LED display, that is, the resolution. 5mm ellipsoidal lamps are mainly used for outdoor displays above P16, 3mm ellipsoidal lamps are mainly used for P12.5, P12, P10 outdoor displays, 3528 chip LEDs are mainly used for indoor displays in P6, P8, 2020 chip LEDs are mainly used for indoor displays such as P2, P3. display screen. Under the premise of the same pitch, the LED device size increases, can increase the display area, reduce the sense of particles, but due to the reduction of the black area, will reduce the contrast; on the contrary, the LED size is reduced, reducing the display area, particles increase, the black area increases, increasing the contrast.
8, consistency
Full-color display is composed of countless red, green, blue LED pixels spelled out, the brightness of each color LED, wavelength consistency determines the brightness of the entire display consistency, white balance consistency, chromaticity consistency. Generally speaking, display manufacturers require device suppliers to provide 5nm wavelength range and 1:1.3 brightness range of the LED, these indicators can be graded by the device supplier through the spectrophotometric color separation machine to achieve. Voltage consistency is generally not required.
As the LED is angled, so the LED full-color display also has the angle directionality, that is, when viewed at different angles, its brightness is incremental or decremental. In this way, red, green, blue three colors LED angle consistency will seriously affect the consistency of the white balance of different angles, directly affecting the fidelity of the display video color. To achieve the red, green, blue three kinds of LED in different angles when the brightness changes to match the consistency of the need for strict scientific design in the package lens design, the original material selection, which depends on the technical level of the packaging supplier. Normal direction white balance and then good display, if the angle of the LED consistency is not good, the whole screen at different angles of the white balance effect will be bad.LED lamp beads of the angle consistency characteristics can be measured by the LED Angle Comprehensive Tester, for the medium and high-grade displays is particularly important.