What are the seven major effects of LED lamp beads on transp

Time:2019-07-16 Browse:

       Transparent LED display is a very common way of promoting publicity in the field of commercial display. We see the words and colors on the screen from time to time on the street every day, but some people will think of transparent LED display when they saw it. What is the screen made, what are the key materials, or what components they need to form.

1, life

       The theoretical life of the LED lamp bead device is 100,000 hours, which is much larger than the working life of other components of the transparent LED display. Therefore, as long as the LED device quality is guaranteed, the working current is suitable, the PCB heat dissipation design is reasonable, and the display production process is rigorous, the LED device is displayed. One of the most durable parts in the screen machine.

       LED devices account for 70% of the price of transparent LED displays, so LED devices can determine the quality of transparent LED displays. China is a big country in the production of LED devices, and it is also a gathering place for transparent LED display.

       The high technical requirements of transparent LED display is the future development trend. The high quality requirements of transparent LED display are not only related to the trend of transparent LED display manufacturers, but also the development of LED display device manufacturers. From the LED device check, promote China's transition from a transparent LED display manufacturing power to a transparent LED display manufacturing power.

2, attenuation characteristics

       When the transparent LED display is operated for a long time, the brightness will drop and the color of the display will be inconsistent, mainly due to the brightness degradation of the LED device. Attenuation of the brightness of the LED will cause the brightness of the entire screen of the display to decrease. Red, green, and blue LED brightness

The inconsistency of the attenuation amplitude will cause the color of the LED display to be inconsistent, which is what we often say about the display screen.

       High quality LED devices provide excellent control of the brightness attenuation. According to 1000 hours of normal temperature lighting 20mA standard, red attenuation should be less than 2%, blue and green attenuation should be less than 10%, so blue and green transparent LED display design should try not to use 20mA current, preferably only 70% to 80 % rated current.

In addition to the characteristics of the red, green and blue LEDs, the attenuation characteristics are affected by the current, the heat dissipation design of the PCB, and the ambient temperature of the display.

3, size

       The size of the LED device affects the pixel distance of the transparent LED display, ie the resolution. The 5mm elliptical lamp is mainly used for outdoor display above P16, the 3mm elliptical lamp is mainly used for outdoor display of P12.5, P12 and P10, and the 3528 type patch LED is mainly used for indoor display of P6 and P8. The 5050 SMD LED is mainly used for semi-outdoor displays such as P16 and P12.5.

       Under the premise of constant dot pitch, the LED device size increases, which can increase the display area and reduce the graininess. However, due to the reduction of the black area, the contrast will be reduced. On the contrary, the LED size is reduced, the display area is reduced, and the graininess is increased. The area of the black area increases and the contrast is increased.

4, perspective

       The viewing angle of the transparent LED display is determined by the viewing angle of the LED bead.

       At present, most of the outdoor display screens use elliptical LEDs with a horizontal viewing angle of 100° and a vertical viewing angle of 50°, and the indoor display screen uses a patch LED with a horizontal and vertical angle of 120°. The display on the highway is generally 30° due to its particularity; a circular LED with a viewing angle is sufficient.

       Some high-rise buildings require a higher vertical viewing angle. The angle of view and brightness are contradictory, and a large angle of view necessarily reduces brightness. The choice of perspective needs to be determined based on the specific application.

5, brightness

       LED brightness is a determining factor in the brightness of the display. The higher the brightness of the LED, the larger the margin of current used, which is beneficial for saving power and keeping the LED stable.

       LEDs have different angle values. When the brightness of the chip is fixed, the smaller the angle, the brighter the LED, but the smaller the viewing angle of the display. Generally, a 100 degree LED should be selected to ensure a sufficient viewing angle of the display.

       For displays with different dot pitches and different line of sight, a balance should be found in brightness, angle and price.

6, failure rate

       Since the LED display is composed of tens of thousands or even hundreds of thousands of red, green and blue LEDs, the failure of any color LED will affect the overall visual effect of the display.

       In general, according to industry experience, the failure rate before the LED display starts to assemble to aging 72 hours before shipment should be no more than three ten thousandth (refer to the failure caused by the LED lamp itself)

7, anti-static ability

       LEDs are semiconductor devices that are sensitive to static electricity and can easily cause electrostatic failure. Therefore, antistatic capability is critical to the life of the display. In general, the LED's human body static mode test failure voltage should not be lower than 2000V.