LCD technology is to inject liquid crystals between two planes with thin grooves. The slots on the two planes are perpendicular to each other (90 degrees). That is to say, if the molecules on one plane are arranged in the North-South direction, the molecules on the other plane are arranged in the East-West direction, and the molecules between the two planes are forced into a 90 degree twist state.
As light travels along the molecular alignment, it is also reversed by 90 degrees as it passes through the liquid crystal. When a voltage is applied to the liquid crystal, the liquid crystal molecule will rotate to change the light transmittance, thus realizing multi-gray-scale display.
LCD relies on polarization filters (sheets) and light itself. Natural light radiates randomly in all directions. Polarization filters are actually a series of thinner and thinner parallel lines. These lines form a net that blocks all light that is not parallel to these lines. The line of the polarized filter is just perpendicular to the first one, so that the polarized light can be completely blocked. Only when the lines of the two filters are completely parallel or the light itself has been twisted to match the second polarized filter can the light penetrate.
The LCD consists of two polarized filters that are perpendicular to each other, so all light that is attempted to penetrate should normally be blocked. However, because the two filters are full of twisted liquid crystals, the liquid crystal molecules will twist 90 degrees after the light passes through the first filter, and finally pass through the second filter.
From the structure of LCD display, whether it is a laptop or a desktop system, the LCD display is a hierarchical structure composed of different parts. LCD consists of two glass panels with thickness specifications of 0.7mm, 0.63mm and 0.5mm (which can also be thinner by physical or chemical thinning). The LCD is separated by a uniform interval of 3-5um containing liquid crystal (LC) materials.
Because the liquid crystal material itself does not emit light, it is necessary to configure additional light source for the display screen. On the back of the liquid crystal display screen, there is a light guide plate (or even plate) and a reflective film. The main function of the light guide plate is to convert the line light source or point light source into a surface light source perpendicular to the display plane. The light from the backlight enters the liquid crystal layer after passing through the first polarization filter layer.
Crystal droplets in the liquid crystal layer are contained in a small cell structure, one or more cells constitute a pixel on the screen. There are transparent electrodes between the glass plate and the liquid crystal material. The electrodes are divided into rows and rows. At the intersection of rows and rows, the rotatory state of the liquid crystal is changed by changing the voltage. The function of the liquid crystal material is similar to that of a small light valve.
Around the liquid crystal material are the control circuit part and the drive circuit part. When the electrodes in the LCD generate electric fields, the liquid crystal molecules will be distorted, and the light passing through them will be refracted regularly, and then filtered through the second filter layer and displayed on the screen.
