An article lets you know how to distinguish the quality of LED digital display in seconds

All in one 2019-01-06

01 LED wavelength control range

Wavelength determines whether the color is pure or not, and whether the color is the same. The method of discrimination is very simple. Usually users do not have professional equipment. How to distinguish with eyes? Firstly, the whole screen should be white, and the screen should be pure white without any other colors. Because the color bias proves that the material and process quality control of the display screen are all wrong. It will become more and more serious if it is used for a long time. Second: knock out red, green, blue monochrome, the color of the central wavelength is what we usually call blue, red and green. If the color is darker or lighter, it proves to be partial wavelength. If a certain color is inconsistent, it proves that the wave difference is too large. The blue-green wave difference is controlled at 3nm and the red wave difference is less than 5nm for the high-quality display screen in the central wavelength range.

02 Light Emitting Tube Perspective

The luminous angle of the luminous tube is the angle between the two observation directions and the normal direction of the same plane when the brightness of the observation direction falls to half of the brightness of the normal direction of the LED digital display. It can be divided into horizontal and vertical perspectives. The horizontal angle of view is 160 degrees and the vertical angle is 120 degrees.

03 maximum brightness

Maximum brightness refers to the brightness of each primary color of the LED digital display at the highest gray level and brightness under a certain ambient illumination. In short, the brightness measured by a light gun in the normal direction when the display screen is set to white 255 by software.

For outdoor LED display, according to the use of the environment, there will be different requirements for maximum brightness, because in the case of strong environmental light, it is required that the brightness of the LED display should be higher, in order to let the masses see clearly the content displayed on the screen. Generally speaking, the maximum brightness requirement of the display screen is lower when it sits south to north. As long as it reaches 4000CD/m2, the display screen sitting north to South can meet the requirement, while the display screen sitting north to South requires that the brightness of the whole screen can reach 7000CD/m2. The requirement of facing east and West is the same as that of facing south, because sunlight will directly shine on the LED display screen for a part of the time. In theory, brightness requirements greater than 5500CD square meter brightness is enough.

04 refresh frequency

It refers to the number of times that the display information of the LED display screen is displayed completely every second in Hz. If the refresh frequency is too low, the human eye will see the LED display jitter phenomenon. When shooting through the camera, there will be a scanning line. The refresh frequency of ordinary people's eyes is more than 300 Hz, that is, the refresh rate is only more than 300 Hz. Normally people will not feel jitter when they watch the LED display screen with the naked eye. If they use cameras to shoot, according to the different settings of different cameras, the minimum requirement is more than 600 Hz to capture the scanning line. High refresh can improve the brightness and color fidelity of the display screen. It can be detected with a digital camera. If it is high refresh, the picture taken by the camera is very clear, there are no snowflakes and scanning lines. This indicator is particularly important when renting screens and television broadcasts.

05 On Contrast

Contrast refers to the measurement of different brightness levels between the brightest white and the darkest black in an image. The larger the difference range, the larger the contrast, and the smaller the difference range, the smaller the contrast. Contrast is very important to visual effect. Generally speaking, the bigger the contrast is, the clearer the image is, and the brighter the color is, while the smaller the contrast is, the whole picture will be gray.

06 Circuit Design Section

Hidden pins and multi-channel water-blocking technology, material fusion technology are adopted to ensure good waterproofing of the lamp. Aluminum package is used to protect the whole circuit completely. High-quality electronic sealing glue imported from Korea is used for front sealing. The height of surface lamp beads is the highest in the industry, and the thickness of filling glue is the highest in the industry. It ensures the normal working environment from -40 to 200 limit. The grade of protection is as high as IP68, which can be used for immersion protection of military industry quality. All environmental factors, such as rainwater, dust, corrosive gas, dew moisture and salt mist, have no effect on the product, and the product quality and performance are very reliable. In addition, it has good fire protection performance.