LCD 工作原理。液晶显示的原理是液晶在不同电压的作用下会呈现不同的光特性.液晶在物理上分成两大类,一类是无源Passive的(也称被动式),这类液晶本身不发光,需要外部提供光源,根据光源位置,又可以分为反射式和透射式两种-LCD works. The principle of liquid crystal display is liquid crystal at different voltages will be presented under different optical characteristics. LCD physically divided into two categories, one category is the passive Passive (also called passive), this type of liquid crystal itself is not luminescent, the need for external provide the light source, according to the light source position, but also can be divided into reflective and transmissive two