Structure of liquid crystal screen
March 21, 2017
TFT-LCD is generally composed of upper substrate module, lower substrate module, liquid crystal, driving circuit unit, backlight module and other accessories. The lower substrate module is mainly composed of lower glass substrate and TFT array. The upper substrate module comprises an upper glass substrate, a polarizing plate and a thin film structure covering the upper glass substrate. The liquid crystal is filled in the gap formed by the upper and lower substrates.
On the inner side of the lower glass substrate, there are a series of conductive glass microplates corresponding to display pixels, TFT semiconductor switching devices and vertical and horizontal lines connecting semiconductor switching devices, which are formed by microelectronic manufacturing processes, such as lithography and etching.
On the inner side of the upper glass substrate, there is a transparent conductive glass plate, which is generally made of indium tin oxide (ITO) material. As a common electrode, it forms a series of electric fields with many conductive microplates on the lower substrate.
If the LCD is color, there are three primary color (red, green and blue) filter units and black spots between the ordinary conductive plate and the glass substrate. The function of black spots is to prevent light from leaking out of the gap between pixels. It is made of opaque material. Because of its matrix distribution, it is called black dot matrix.