How an LCD Display Works? Learn with Block Diagram

An LCD (Liquid Crystal Display) is a flat panel display technology that uses liquid crystals to produce images. LCD displays are commonly used in various electronic devices such as televisions, computer monitors, smartphones, tablets, and digital clocks. In this article, we are going to learn how an LCD display works with a block diagram that will help us to easily understand the working principle. 

For information, LCD displays offer several advantages, including low power consumption, slim profile, wide viewing angles, and the ability to display high-resolution images. However, they may have some limitations such as limited contrast ratio and slower response times compared to other advanced display technologies like LED Display or OLED (Organic Light-Emitting Diode).

Here, you can see the block diagram for understanding the working principle of an LCD Display.

Click on the image to Enlarge

As per the above block diagram, Here are the step-by-step procedures that describe how an LCD display works,

1. LCD (Liquid Crystal Display) has special materials called liquid crystals that can change the way light passes through them. 
2. Normally, when the display is in off condition or the screen is fully black the liquid crystals are arranged in a way that blocks light from passing through the LCD. 
3. The LCD Display has polarizers which are similar to filters, that only allow light waves to pass through in a specific direction. One polarizer is placed in front, and the other is placed behind the liquid crystals. 
4. Behind the LCD, there is a light source called a backlight that shines through the screen, making the images bright and visible.
5. To produce different colors on the display, an LCD uses tiny color filters for each pixel. These filters can produce red, green, and blue colors, which combine to create a full-color image.
6. So each pixel in the LCD contains liquid crystals and color filters. By controlling the electric current to each pixel, the LCD produces images with different colors. 
7. Now when an electric current is applied to the LCD, the liquid crystals change their orientation to allow the light to pass through instead of blocking it. Once the liquid crystals allow the light to pass through, they align with the second polarizer, allowing light to pass through the LCD and creating a visible image.
8. The combination of liquid crystals, color filters, and pixel control by electric current creates the images and colors you see on an LCD screen.

So, in summary, an LCD display works by using liquid crystals that change their orientation when an electric current is applied. This manipulation of the liquid crystals, along with color filters and pixel control, allows the LCD to produce different colors and create the images we see on the screen.

Read Also: 

• How an LED Display Works? Learn with Diagram