At present, the indoor splicing large screen market micro-pitch LED splicing screen, DLP rear projection splicing screen, LCD liquid crystal splicing screen three-point world, of which the micro-pitch LED splicing screen is the momentum, its no seam, high brightness, high gray, The high contrast ratio and long service life are unmatched by other splicing screens, and have been recognized by the market, quickly occupying a large share of the indoor splicing market. Bringing such excellent performance to the micro-pitch LED splicing screen is inseparable from the key device used in the micro-pitch LED manufacturing--LED lamp bead. Let me give a brief introduction to the LED lamp bead.

Ubiquitous LED lamp beads

LED lamp bead is the most used component of micro-pitch LED display, which affects the display effect of micro-pitch LED. For the application of indoor micro-pitch LED, LED lamp bead is mostly used for dark and gold wire bonding. An SMD lamp bead. LED lamp beads have become the key components of micro-pitch LED displays for three reasons:

1. LED lamp bead is the most used component of micro-pitch LED display. Taking P1.6 micro-pitch LED display as an example, the usage per square meter is as high as 360,000.

2, LED lamp bead performance indicators directly affect the performance of the micro-pitch LED display body, affecting the audience's evaluation of the display.

3, LED lamp beads account for the largest proportion of the overall cost of micro-pitch LED display, up to 30% ~ 70%.

The effect of LED lamp beads on the micro-pitch LED display

1. Influence on brightness The brightness of the micro-pitch LED display depends on the current flowing into the LED lamp bead and the brightness performance of the LED bead itself. The higher the current used by the LED lamp bead, the greater the brightness of the micro-pitch LED display. The high-quality LED lamp bead has a good light conversion rate, and the extremely low current can emit high-brightness light. It is beneficial to keep the micro-pitch LED display stable.

2. Influence on out-of-control rate Since the micro-pitch LED display consists 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. Generally speaking, according to industry experience, the failure rate before the assembly of the LED display to the aging 72 hours before shipment should be no more than three ten thousandth (refer to the failure caused by the LED lamp itself), high quality LED lamp beads The failure rate is very low, and the micro-pitch LED display with high-quality LED lamp bead can control the out-of-control rate below one hundred thousandth.

3, the impact on the service life LED lamp beads theoretical life is 100,000 hours, far greater than the working life of other components of the micro-pitch LED display, so as long as the LED lamp bead quality assurance, working current is appropriate, PCB thermal design is reasonable, display The production process is rigorous, and the LED lamp bead will be one of the most durable components in the display machine. The micro-pitch LED display with high-quality LED lamp bead can last up to 100,000 hours and the MTBF is up to 50,000 hours.

4. Influence on the viewing angle The viewing angle of the micro-pitch LED display is determined by the viewing angle of the LED lamp bead. At present, the indoor display screen mostly uses LED lamp beads with horizontal/vertical angles, so that the horizontal/vertical viewing angle of the micro-pitch LED display can reach 160 degrees.

5, the impact of pixel spacing The size of the LED lamp bead affects the pixel spacing of the LED display and the full screen resolution. SMD0707 LED lamp bead is mainly used with P1.5 and below micro-pitch LED display. SMD1010 LED lamp bead is mainly used for P1.6, P1.9, P2.0 micro-pitch LED display. SMD2121 LED lamp bead is mainly used. For P2.5, P3 micro-pitch LED display. Under the premise of constant dot pitch, the LED lamp bead size increases, which can increase the display area and reduce the graininess. However, since the black area is reduced, the contrast is reduced. On the contrary, the LED lamp bead size is reduced, and the display area is reduced. The graininess increases, the area of ​​the black area increases, and the contrast is increased.

6. Influence on brightness/chromaticity/white balance consistency The micro-pitch LED display is composed of countless red, green and blue LEDs. The brightness and wavelength consistency of each color LED determine the whole. Brightness consistency, white balance consistency, and chroma consistency of the display. In general, display manufacturers require device vendors to provide LED lamp beads with a 5 nm wavelength range and a brightness range of 1:1.3. These specifications can be achieved by device suppliers through a spectral color separation machine. Since the LED bead is angled, the micro-pitch LED display also has angular orientation, that is, the brightness is increased or decreased when viewed at different angles. In this way, the angular consistency of the red, green, and blue LEDs will seriously affect the consistency of white balance at different angles, directly affecting the fidelity of the display video color. In order to achieve the consistency of the brightness changes of the red, green and blue LEDs at different angles, it is necessary to strictly carry out scientific design on the packaging lens design and raw material selection, depending on the technical level of the packaging supplier. In the normal direction, the white balance is good. If the angle of the LED bead is not consistent, the white balance effect at different angles of the whole screen will be bad. The angle uniformity of the LED lamp bead can be measured by the LED angle comprehensive tester, which is especially important for medium and high-end displays.

7, the impact of anti-static ability LED lamp bead is a semiconductor device, sensitive to static electricity, it is easy to cause static failure, so anti-static ability is critical to the life of the display. The high-quality LED lamp beads can withstand the test voltage of 50Hz, 1500V (AC RMS) for 1 minute without insulation breakdown. 8. Influence on attenuation characteristics After a long time of operation, the LED display will show a decrease in brightness and inconsistent display color, mainly due to the brightness degradation of the LED lamp bead. The attenuation of the brightness of the LED bead will cause the brightness of the entire screen of the display to decrease. Inconsistent brightness attenuation of red, green and blue LEDs will cause inconsistencies in the color of the LED display, which is what we often say about the display. High quality LED beads 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 LEDs should not use 20mA current in the display design, 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.

LED lamp beads features

1, 4-PIN RGB package, the chip is arranged in a straight line;

2, using a black package substrate to improve color contrast;

3, the product is light in weight, the weight of a single LED is as small as 1.0mg;

4, can achieve full black RGB package; light loss 25%;

5, can achieve the minimum size of 0.5 * 0.5mm RGB package;

6, the surface of the product matte treatment, the screen light is softer;

7, using silicone compression molding technology to improve product temperature resistance, UV resistance, stress resistance. The micro-pitch LED display with high-quality LED lamp bead is adjustable from 0 to 1200 cd/m2, with 160 degree horizontal/vertical super wide viewing angle, and the whole screen has a runaway rate as low as 100,000, and has a long time of 100,000 hours. Service life, average trouble-free working time up to 50,000 hours, brightness uniformity of not less than 98%, chromaticity uniformity ±0.003Cx, within Cy, with up to 99% light utilization, power consumption is only half of DLP and LCD To, energy-saving, environmentally friendly, easy to maintain, such outstanding performance, has won the recognition of the majority of users.

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July 16, 2024