A Liquid Crystal Display (LCD) is a flat-panel display technology that uses liquid crystals to control the passage of light and produce images or information on a screen.

Definition

An LCD is an electronic display that does not produce its own light. Instead, it relies on a backlight that shines through a layer of liquid crystals, which can be aligned or twisted by electrical signals to either block or allow light through.

What Are Liquid Crystals?

Liquid crystals are substances that have properties between those of a liquid and a solid. They can flow like a liquid but maintain molecular order like a solid. When an electric current is applied, their orientation changes — which alters how they interact with light.

Basic Structure of an LCD

Backlight – Usually LEDs that provide illumination.

Polarizing Filters – Two filters that only allow light waves in a certain direction.

Glass Substrates – Hold the liquid crystal material in place.

Liquid Crystal Layer – Responds to voltage and twists to block or pass light.

Color Filters – Tiny RGB (red, green, blue) filters for each pixel to create color.

How It Work

Light from the backlight passes through the first polarizer.

The liquid crystals twist the light depending on electric signals.

Twisted light passes through the second polarizer and color filters to form the image

 In Simple Terms

Think of LCD as window blinds for light — the liquid crystals "open" or "close" to let light through or block it, forming text, images, or video.

TFT LCD Display product links for reference