1.Viewing angle
LED display angle of view depends on the LED pixel bead's viewing angle.
LED display angle depends on the LED pixel beads perspective. At present, most of the outdoor display screen selection angle of 100 °, vertical viewing angle of 50 °; oval LED pixel beads, indoor display is selected horizontal and vertical are 120 °; SMD LED pixel beads. Expressway on the display because of its special nature generally use 30 °; angle of the circular LED pixel beads is enough. Some high-rise display on the vertical viewing angle requirements are higher. Perspective and brightness are contradictory, a large perspective will inevitably reduce the brightness. The choice of perspective needs to be determined according to the specific purpose.
2.brightness
LED brightness is an important determinant of the brightness of the display. LED brightness is higher, the greater the use of current margin, to save power, keep the LED stability is good. LED has a different angle value, the same brightness of the chip, the smaller the angle, LED is brighter, but the smaller viewing angle is. Generally should choose 100 degrees LED to ensure that the display screen enough angle. For a different point spacing and different line of sight of the display, should be in brightness, angle and price to find a balance point
3.failure rate
As the full color display by tens of thousands or even hundreds of thousands of groups of red, green and blue LED composed of three pixels, any color LED failure will affect the overall visual effects of the display. In general, according to industry experience, LED display aging 72 hours after the failure rate should not be higher than three ten thousandths (referring to the LED pixel itself caused by the failure)
4. anti-static ability
LED is a semiconductor device, sensitive to static electricity, easily lead to electrostatic failure. So the anti-static capacity of the display life is essential. In general, LED body static mode test failure voltage should not be less than 2000V.
5. life expectancy
LED device theoretical life of 100,000 hours, much larger than the LED display other parts of the working life, so as long as the LED device quality assurance, the working current is appropriate, PCB cooling design is reasonable, the display production process rigorous, LED devices will be in the display One of the most durable parts.
LED devices accounted for 70% of the proportion of LED display prices, so that LED devices can determine the quality of LED display quality.
6. attenuation characteristics
LED display after a long period of time will appear after the decline in brightness and display color inconsistencies, mainly due to the brightness of LED devices caused by attenuation. LED brightness attenuation will cause the display screen brightness reduction. Red, green, blue LED brightness attenuation of the inconsistency will cause the LED display color inconsistencies, that is, we often say that the display blurred phenomenon. High-quality LED devices can well control the brightness attenuation. According to 1000 hours at room temperature lit 20mA standard, red attenuation should be less than 2%, blue, green attenuation should be less than 10%, so blue, green LED design in the display as far as possible not to use 20mA current, preferably only 70% to 80 % Of the rated current.
In addition to the attenuation characteristics of red, green and blue LED itself, the use of current, PCB board thermal design, display the use of ambient temperature, etc. are affected by attenuation.
7. size
The size of the LED device affects the pixel distance of the LED display, that is, the resolution. 5mm oval lamp is mainly used for P16 above the outdoor display, 3mm oval lamp is mainly used for P12.5, P12, P10 outdoor display, 3528 SMD LED is mainly used for P6, P8 indoor display, 2020 SMD LED is mainly used for P2, P3 and other indoor display. In the premise of the same pitch, LED device size increases, can increase the display area, reduce the grainy, but because the black area decreased, will reduce the contrast; the contrary, LED size decreases, reducing the display area, grain increased , Black area increased, increasing the contrast.
8.consistency
Full-color display is composed of numerous red, green, blue LED composed of pixels, each color LED brightness, wavelength consistency determines the brightness of the entire display consistency, white balance consistency, consistent color Sex. In general, the display manufacturers require device suppliers to provide 5nm wavelength range and 1: 1.3 brightness range of the LED, these indicators can be achieved by the device supplier through the spectrophotometer classification. The consistency of the voltage is generally not required.
As the LED is angular, so full-color LED display also has the angular direction, that is, in different angles, the brightness is increased or decreasing. In this way, the red, green, and blue colors of the three angles of LED consistency will seriously affect the consistency of different angles of white balance, a direct impact on the display video color fidelity. To achieve red, green and blue LED at different angles when the brightness of the matching consistency, the need for packaging lens design, raw material selection on the rigorous scientific design, depending on the packaging supplier's technical level. Normal direction white balance no matter how good the display, if the LED angle consistency is not good, the whole screen different angles of the white balance effect will be bad. LED pixel beads angle consistency characteristics can be measured using LED angle tester, for high-end display is particularly important.
INMO Technology Ltd-A LED display suppliers and solution providers
contact person: Carmen huang
whatsapp:+86-15306962121
Tel: +86-0595-28234091
Fax: +86-0595-28234091
Mail: info@inmotron.com
Web: www.inmotron.com
No comments:
Post a Comment