Why does the monochrome LCD display display when it is not lit?

Generally, the LCD screen will not produce its own display when it is still. This problem occurs more or less only when an object or hand touches the LCD screen, but it will disappear soon, and the cause of this phenomenon on the LCD screen is "static electricity."

Static electricity is an electric charge in a static state. In the dry autumn and winter, people also encounter this phenomenon in daily life: when undressing, they often hear crackling noises; when holding the doorknob with their hands, they will suddenly feel a needle-like tingling. In severe cases, it often makes "pop, pop, pop" sound, which is the static electricity that occurs in the human body.

Most of the liquid crystal electronic products have circuit boards, capacitors, diodes and other components. They generally allow very small currents to pass. If the human body has a lot of static electricity, the current generated after touching the electronic products is very likely to break down the components and cause damage. This phenomenon can also occur on monochrome dot matrix LCD display, especially segment screens. For example, when you tear off the protective film on the surface of the LCD screen, some of the segments may be displayed due to static electricity, indicating that there is a problem with the LCD screen itself.