Points to consider when choosing an LED display

Now, with the advancement of social technology and the development of outdoor advertising, people's requirements for outdoor media are getting higher and higher, so large LED screens are beginning to emerge. The large-scale LED display is a perfect combination of technology and media, and its product applications involve financial securities, sports, airports, railways, stations, highway transportation, commercial advertising, post and telecommunications and many other fields. How to choose a high-quality LED large screen is a problem that many buyers need to consider. Let's talk about this problem from the key aspects of LED large screens:

1. Flatness

The surface flatness of the LED display should be within ±1mm to ensure that the displayed image is not distorted, and local protrusions or recesses will cause a blind angle in the viewing angle of the LED display. The quality of flatness is mainly determined by the production process.

2. Brightness and viewing angle

Brightness and viewing angle The brightness of the indoor full-color LED display must be above 1800cd/m2, the brightness of the outdoor full-color LED display must be above 5000cd/m2, and the brightness of the outdoor led strip screen must be above 2000cd/m2 to ensure The normal brightness of the LED display is required, otherwise it will be difficult to see the displayed content because the brightness is too low. The brightness is mainly determined by the quality of the LED die. The size of the viewing angle directly determines the audience of the LED display, so the larger the better, the size of the viewing angle is mainly determined by the packaging method of the die.

Three, white balance effect

White balance effect The white balance effect is one of the most important indicators of the LED display. In color science, pure white will be displayed when the ratio of the three primary colors of red, green and blue is 3:6:1. If there is a slight deviation in the actual ratio, there will be a deviation in the white balance. Generally, pay attention to whether the white is blue or yellow. Green phenomenon. The quality of the white balance is mainly determined by the control system of the LED display, and the die also has an impact on the color reproduction.

Fourth, the reducibility of colors

Color reproducibility The color reproducibility refers to the color reducibility of the LED display. The color displayed by the LED display 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 LED display. It is a phenomenon of module necrosis. The main reason is that the quality of the connectors used in the LED display is not good enough. The dead point refers to a single point that is always bright or black that appears on the LED display. The number of dead points is mainly determined by the quality of the die.

Six, whether there are color blocks

Whether there is a color block, the color block refers to the obvious color difference between adjacent LED modules. The color transition is based on the module. The color block phenomenon is mainly caused by the poor control system, low gray level, and scanning Caused by lower frequency.

Seven, gray scale

The gray level is the number of technical processing levels between the darkest and the brightest of the led display screen. The higher the gray level, the richer the color and the brighter the color; the more delicate the picture, the easier it is to show rich details. At present, the domestic LED display mainly adopts an 8-bit processing system, that is, 256 (28) gray levels. The simple understanding is that there are 256 brightness changes from black to white. Using the three primary colors of RGB can form 256×256×256=16777216 colors. That is commonly referred to as 16 mega colors.

8. Refresh frequency

The refresh rate refers to the number of times that the LED display screen is repeatedly displayed by the display screen. In theory, the higher the refresh rate, the better the display effect. Generally speaking, the indoor LED display refresh rate in the civilian or commercial LED display series is greater than 180HZ , The refresh rate of the outdoor LED display is greater than 300HZ.