How does the LCD display display characters or images? Let's first understand the display principle of the liquid crystal display. Its basic structure is shown in the figure below:
The liquid crystal molecules are encapsulated by two glass (Glass) made of transparent electrodes (Electrode) and epoxy resin around them (in a vacuum environment, the liquid crystal molecules are filled through the injection port reserved on the sealing frame, and then the resin is used Glue seals the injection port), and then paste a polarizer (Polarizer) whose polarization directions are perpendicular to each other on the outer surface of the upper and lower glass, and a reflector (Reflector) at the bottom. The basic liquid crystal display device is done.
In the TN LCD screen (what is TN?), the inner surface of the glass is also coated with an alignment film (Polymer) and has been oriented. The direction of the alignment film processing is consistent with the polarization direction of the adjacent polarizing film. The glass surfaces are arranged in parallel. Since the orientation processing directions of the inner surface of the upper and lower glass sheets are perpendicular to each other, the liquid crystal molecules are twisted at 90 degrees between the two sheets of glass. This is the name of the Twisted Nematic (TN) liquid crystal display device originally comes from.