LCD (Liquid Crystal Display) may not be a new term for many users, but the history of this technology may be far beyond our imagination - as early as the end of the 19th century, Austrian botanists The discovery of liquid crystals, that is, liquid crystals, that is to say, a substance has both the fluidity of liquids and certain arrangement properties similar to crystals. Under the action of the electric field, the arrangement of the liquid crystal molecules will change. Thus affecting its optical properties, this phenomenon is called the electro-optic effect. Using the electro-optical effect of liquid crystals, British scientists created the first liquid crystal display (LCD) in the last century. Aligned liquid crystals are widely used in today's liquid crystal displays. If we look at it microscopically, we will find that it looks like a cotton swab. Compared with the traditional CRT, the LCD is not only small in size, thin in thickness (the thickness of the current 14.1-inch machine can be only 5 cm), light in weight, low in energy consumption (1 to 10 microwatts/square centimeter), and low in operating voltage (1.5 to 6V) and no radiation, no flicker and can be directly matched with CMOS integrated circuits. Due to its many advantages, LCD has entered the desktop application field since 1998.