Understanding of outdoor LED display 'water ripple phenomenon'

In the actual application of outdoor LED display screens, the 'LED display water ripple phenomenon' has become an important obstacle to the high-definition display of the display screen. So how does the 'LED display water ripple phenomenon' cause it? What do you know about the 'water ripple phenomenon in LED displays'? LED display manufacturers will take everyone to understand the phenomenon of outdoor LED display 'water ripples' through this article!



1. The difference between water ripple and scanning line phenomenon of full-color LED display



1. Water ripples: generally present in an irregular arc-shaped diffusion state!



2. Scanning line: the horizontal black stripes are straight lines, mainly due to the low refresh of the display screen and being captured and presented by the camera!



2. Full-color LED display 'Water ripple' scientific name 'Moore'



When shooting with a digital camera, if there are dense grain textures, inexplicable water-like streaks will often appear. This is the moiré pattern. Simply put, the moiré pattern is a manifestation of the beat principle. Mathematically speaking, two equal-amplitude sine waves with close frequencies are superimposed, and the amplitude of the synthesized signal will change according to the difference between the two frequencies.



3. The process of moiré generation in full-color LED display screen



1. Two stripes with slightly different spatial frequencies have the same position of the black line at the left end. Due to the different spacing, the gradually line stripes to the right cannot be overlapped.



2. The two stripes overlap, and the white line can be seen because the black line overlaps on the left. The right side is gradually misplaced, the white line is facing the black line, and the overlap result becomes completely black. There are white lines and all black changes, forming a moiré pattern.



Fourth, LED full-color display screen produces moiré phenomenon process



The pixel distribution density of the full-color display is exactly in the interval that the CCD can distinguish. The inevitable digital camera will still interpret some of the recognizable results, but it will also add unrecognizable grayscale areas. The sum of the persons will form regular lines, and the response is visually periodic ripples.



5. Methods to eliminate moiré



1. Change the camera angle. Since the angle of the camera shooting objects will cause moiré, slightly changing the angle of the camera, by rotating the camera, you can eliminate or change any moiré that exists.



2. Change the camera position. In addition, by moving left and right or up and down to change the angular relationship, moiré can be reduced.



3. Change the focus. Too sharp focus and high detail may cause moiré. Changing the focus slightly can change the sharpness and help eliminate moiré.



4. Change the focal length of the lens. Different lens or focal length settings can be used to change or eliminate moiré.



5. Use the front filter to install directly in front of the CCD to make the exposure conditions meet the spatial frequency, thoroughly filter the high spatial frequency part of the image, and reduce the chance of occurrence of moiré on the LED display, but this will also be reduced simultaneously The sharpness of the image.



6. Use software to process. Such as NikonCapture or Photoshop plug-ins, etc., to eliminate any moiré on the final image.

Demo is the leading manufacturer of About Us and related products.
Demo Photoelectric Technology (Wuxi) Co., Ltd. provides which will help you led light engine in a durable and reliable way. To learn more, go to Demo Led Module.
Latest technology and manufacturing equipment has improved the quality of About Us.