Regarding how a "layman" distinguishes the LED display quality of the , he does not fully understand the quality of the LED display . Under normal circumstances, it is completely relied on by the sales staff to justify it. Sometimes it is difficult to convince users. The following types of identification are full-color A simple method for the quality of the display, I hope it can be helpful when you buy a full-color display.
The a led display quality of can be signed from the following aspects:
1. Flatness
The surface flatness of the display screen should be within ±1mm to ensure that the displayed image is not distorted, and local protrusions or recesses will cause a blind spot in the viewing angle of the display screen. The gap between the box and the box, and the gap between the module and the module should be within 1mm. If the gap is too large, the boundary of the display screen will be obvious and the vision will be uncoordinated. The quality of flatness is mainly determined by the production process.
2. Brightness and viewing angle
indoor full-color screen The brightness of the must be above 800cd/m2, and outdoor full-color screen the brightness of the must be above 5000cd/m2 to ensure the normal operation of the display, otherwise the displayed image will not be clear because the brightness is too low. The brightness of the display screen is not as bright as possible, it should match the brightness of the LED package. Blindly increasing the current to increase the brightness will cause the LED to decrease too quickly, and the life of the display screen will drop rapidly. The manufacturer can be required to provide a parameter report to confirm. The brightness of the screen is mainly determined by the quality of the LED die.
The viewing angle refers to the maximum angle at which you can see the entire screen content from the two measurements of the screen. The size of the viewing angle directly determines the audience of the display screen, so the larger the better. The viewing angle should be above 150 degrees. The size of the viewing angle is mainly determined by the packaging method of the die.
Several coups to teach the "layman" how to distinguish the led display quality of the
3. White balance effect
The white balance effect is one of the most important indicators of the display. In color science, pure white will be displayed when the ratio of the three primary colors of red, green and blue is 1:4.6:0.16. If there is a slight deviation in the actual ratio, there will be a deviation in white balance. Generally, pay attention to whether the white is blue or yellow. Green phenomenon. When monochromatic, the brightness difference and wavelength difference between the LEDs are as small as possible. Standing on the side of the screen, there is no color difference or color cast, and the consistency is better. The quality of the white balance is mainly determined by the LED die brightness wavelength ratio and the control system of the display screen. The die also has an impact on the color reproduction.
4. Color reduction
Color reproducibility refers to the reproducibility of the color of the display screen, that is, the color displayed on the display screen must be highly consistent with the color of the playback source, so as to ensure the realism of the image.
5. Whether there is mosaic or dead spot phenomenon
Mosaic refers to the small four squares that are always bright or black that appear on the display. It is the phenomenon of module necrosis. The main reason is that the quality of the IC or connectors used in the display is not good enough. Dead point refers to a single point that is always bright or black that appears on the display. The number of dead points is mainly determined by the quality of the die and whether the manufacturer's anti-static measures are perfect.
6. With or without color blocks
Color block refers to the obvious color difference between adjacent modules. The color transition is based on the module. The color block phenomenon is mainly caused by poor control system, low gray level, and low scanning frequency.
7. Display stability
Stability refers to the of the LED display screen reliable quality in the aging stage after it is made into a finished product. It can be judged by asking the manufacturer for the aging record to get the status of the screen body during aging.
8. Security
The led display is composed of multiple cabinets, and each cabinet must be grounded for foreign visitors, and the grounding resistance should be less than 0.1 ohm. And can withstand high voltage, 1500V 1min without breakdown. Warning signs and slogans are required at the high-voltage input terminal and the high-voltage wiring of the power supply.
9. Packing and transportation
LED display screens are valuable goods and weigh a lot. The packaging method used by the manufacturer is very important. Generally, it is packaged in a single box, and each side of the box must be protected by a buffer, and there is not much room for internal movement during the transportation of the box. The outer packing box must be clearly marked.