Liquid Crystal Display (LCD)

by Monika Dadool 06-May-19

0 117

LCD (Liquid Crystal Display) is a super-thin technology consists of solid and liquid states of matter in which Liquid Crystals are used to create a visible image. This technology generally plays its major role on the display of computer screen, television and mobile devices.

Basic functions of LCD
a) It works on the principle of blocking light
b) Polarization takes place through polarization filters
c) Three colors i.e. Red, Green and Blue are required to glow a pixel
d) When a voltage is provided on it, its smart molecules align itself and also controls light intensity

Components of LCD:
* Liquid crystal
* Light wave
* Polarized filters
* Back light
* Color filter
* Negative electrode
* Positive electrode

Liquid Crystal
Liquid crystal is neither a liquid nor a solid but its properties match with crystalline solid which mean molecules arrangement is in particular pattern but it is not in a fixed shape. There are different type of liquid crystals found like twisted, Nematic, and Smectic. But in LCD, twisted Nematic crystals are used, in which molecules of the arrangement twist into 90 degree.

Light wave: It travel like transfer wave. This wave contains two components in it i.e. electrical and magnetic which propagate each other by 90 degree angle. They both are mutually perpendicular to each other.

Polarization: Movement of light in one direction i.e. alignment of light in one axis. Polarization filter is used to access light in X and Y axis

Back light: used to create an image.

Color filters: They are attached with transistor and capacitors through which intensity of light can be controlled.

Positive and negative electrodes: They permits crystal molecule to twist and untwist.

Screen pixel:  It is a main part where image is contains up to lakhs of pixels which permits image on the screen. There are mainly three types of color found in pixel i.e. RGB.

Back light produced in a scattered form, travel through vertical polarize axis filter. On applying voltage, it goes through liquid crystal. The liquid crystal gets twisted and propagates which in turn convert the vertical polarized light into horizontal polarized light. At last, it passes through horizontal polarized filter, which is a color filter that control light intensity. The light gets received on pixel and according to the intensity, the pixel get glow.



    No Comments Yet.

Leave a Reply