LED display screen now is the most widely used and the most eye-catching advertising carrier in the outdoor media. With the rapid development of science and technology today, LED electronic display screen is widely used in various areas of government, military, education, finance, industry and commerce, postal services, security, traffic, communication, electric power, sports. To choose a high quality LED display, Verypixel recommends that you should know about the following aspects: 

1. Brightness and View Angle: The Brightness of Indoor Full Color Screen must be over 1800cd/m2 , the brightness of outdoor LED display should be over 5000cd/m2, the brightness of outdoor LED Strip Display should be over 5000cd/m2, so that it can guarantee the normal work of screen, or it won't see the image if the brightness is too low. The Brightness intensity is mainly decided by the LED chip.

VP-GIGA-outdoor LED steel strip display

How many audience can be hold is directly depend on how big the visual angle is, so the bigger the better. The size of the viewing angle is mainly determined by the encapsulation method of LED chip. 

2. Flatness: The surface flatness of electronic screen must be within±1mm, in order to ensure that the LED display image is not distorted, the visual angle of local convex or concave will result in the dead space of display . The quality of the flatness is mainly decided by the production process.

3. Color Reduction: Color Reduction refers to the reduction of the color LED display, it mean the color of LED screen must be consistent with the color of playback source , so as to ensure the authenticity of images.

4. White balance effect: White balance effect is one of the most important indicator of display. Color Science show the primary colors red,green and blue are on the ratio of 3:6:1, it will show the pure white color, if the real ratio is deviated it will appear white balance, generally we should pay attention to a bluish white, yellowish green phenomenon. White balance effect is mainly decided by the control system of the display, tube LED chip also can effect the color reducing.

5. Whether there is Color lump or not: Color lump refers to the obvious color aberration exist between the adjacent module, color transition in units of modular, because of poor control system,low gray level and low scanning frequency are caused color lump phenomenon. 

6. Whether there is a phenomenon of Mosaic and Dead Spot: Mosaic refers to the small block which is always bright or always dark, that is the phenomenon of dead module, the main reason is adapted the poor quality connector of screen. Dead spot refers to the single point appears on the screen of the constant light or dark, the quantity of dead spot is mainly decided by the LED chips.

VP-Fastile-P10 front access indoor LED display screens

7. Gray Scale: Gary Scale refers to the technical processing series from the dark to the brightest of the LED Display,the higher the gray scale is, the richer the color is, and the more gorgeous the color is; the picture is more exquisite, and it is easy to show the rich details. At present, the LED display mainly adopt 8 bit processing system, namely, 256 (28) level. Simple understanding is from black to white, there are 256 types of brightness variations. The RGB tricolor can constitute a 256 x 256 x 256=16777216 colors. That is to say, 16.7 millions color.

The LED Display of Verypixel mainly adopt 10 bits (10 bit) treatment system, namely the 1024 gray level, RGB values can form 10.7 billion colors. Although gray is the determined factors of number of colors, but it is not to say "the bigger, the better". Because the resolution of the human's eye is limited, furthermore, the increase system digit will involve a system of video processing, storage, transmission, scanning and other aspects of change, cost will be increase, the price will be drop. Generally speaking, civil or commercial grade products can use 8 bits (8 bit) system, broadcast products can use 10 bits (10 bit) system.

8. Refresh Frequency: The refresh frequency refers to the repeated show times of LED display visions,in theory the higher the refresh frequency is, the better the display effect will be, generally speaking, civil or commercial grade LED display products in indoor LED display refresh frequency is greater than 180HZ, outdoor LED screen refresh rate is greater than 300HZ.

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