How is the LED display fan screen realized? In recent years, in large shopping malls or activities, you will always see the figure of "LED display fan", which looks exactly like a fan, but when rotated, it can display a variety of patterns, and some can display dynamic 3D patterns. , Very cool, every time you see it, you can always stop and watch, play a very good role in publicity and promotion. So how does the LED display fan display the pattern?

  Strictly speaking, this so-called "fan" is just a vivid name. In fact, it is a "rotating LED display fan", and its professional name is called holographic 3D smart screen. After the power is turned on, the "fan blades" begin to rotate, and while rotating, they can present a 3D image, which is cool and realistic. At the same time, according to the size and color of the pattern, the LED display fan can hide its fan blades well. Because there is no frame and no fixed screen, the dynamic picture is like floating in the sky, which is very realistic.

  The 3D smart dazzling screen not only uses the hardware of rotating LEDs, but also takes advantage of the persistence of vision of the human eye. Regarding the hardware configuration of the rotating LED, in simple terms, it calculates the changing frequency of the LED light according to the rotation speed of the "fan blade". When different LED lights are lit at different times, different patterns will appear. The so-called persistence of vision refers to the fact that when the human eyes are observing the scene, the light signal is transmitted to the brain nerves. It takes a short period of time. After the action of light is over, the visual image does not disappear immediately, and the human eyes can continue to maintain its When the image is about 0.1 second, this kind of residual vision is called "after-image", and this phenomenon of vision is called "persistence of vision".

  Generally speaking, one or more strings of LED lights are arranged on the fan blades of the fan, here it is assumed that there are 20, and the numbering is 1 to 20 at a time from the axis to the edge of the fan blade. In order to briefly explain the principle, assume that the fan speed is 600 revolutions per minute, and that the LED light is at 0 degrees directly above the fan at 0 seconds, then if you want to show the effect of 6:00 on the fan , The minute hand needs to point directly above, and the hour hand points directly below. Then you need to light up 1~20 to display the minute hand at 0 second, light 1 to 10 to display the hour hand at 0.05 second, and then light 1 to 20 to display the minute hand at 0.1 second, 0.15 second At this time, the hour hand will be lighted up from 1 to 10, and so on, so that the human eye will receive a complete image of the clock at 6:00. For complex patterns, LED fans will have more complex structures and programming equipment. Through the combination of the rotation of the LED light bar and the phenomenon of persistence of vision, the rotating LED fan that people see will appear a dynamic 3D picture.