If you look through previous physics books, you will find that people often have a tendency, called "persistence of vision" phenomenon, where we can continue to perceive things even if they no longer appear in front of us, and we can see "persistent images" , rather than a discrete set of static images.
The LED light source flashes at a high frequency that is imperceptible to the naked eye, so we see the light on until we turn the power off completely. Likewise, a video is actually a series of images captured in rapid succession in frames per second, and when we play games together, this continuous visual trick our brains into turning the screen The events above are viewed as a continuous fluid motion.
When the number of frames per second exceeds the frequency of the LED light source, the mobile phone camera shows an obvious flickering effect, which is the stroboscopic effect.
The LED light will flicker when it is quickly switched on and off. Whether it flickers or not mainly depends on the nature of the current supplied to it. Typically, LED lights flicker at such a high frequency that they are not directly detectable, or invisible, to the human eye. Therefore, one can rest assured that any visible camera flicker is in fact the lights operating normally, and the only ones that should be concerned are humans. blink of an eye. However, saying that LED lights are always flashing when running is a very broad statement.
