When shopping for a liquid-crystal display (LCD), you may come across active-matrix LCDs. It’s one of the most common types of LCD technologies. Active-matrix LCDs are used in everything from computer monitors and smartphones to industrial control systems, touchscreen panels and more. What is an active-matrix LCD exactly, and how does it work?
The Basics of Active-Matrix LCDs
An active-matrix LCD is a type of flat-panel display that’s characterized by the use of transistors in rows and columns on the top layer. Like all LCDs, they feature liquid pixels consisting of an organic material. These liquid pixels are embedded under the top layer and over the backlighting layer. The backlighting is designed to illuminate the liquid pixels. During use, active-matrix LCDs produce illumination from the backlighting layer that projects through the liquid pixels. Active-matrix LCDs are different, though, because they have a grid of transistors.
In basic terms, active-matrix LCDs use a grid or “matrix” of transistors for image control. The images displayed by an active-matrix LCD are controlled by its transistors, which are found on the top layer.
How Active-Matrix LCDs Work
While they may sound complex, active-matrix LCDs use a relatively simple method of operation. As previously mentioned, they consist of rows and columns of transistors. This grid-like arrangement of transistors is found on the top layer. Active-matrix LCDs are capable of turning on rows independently of each other. At the same time, they can supply an electrical charge to specific columns. These actions ensure that only the appropriate pixels in the correct area are activated.
It’s important to note that there are several specific types of active-matrix LCD technology, some of the most common being:
- Twisted nematic (TN)
- In-plane switching (IPS)
- Super in-plane switching (S-IPS)
The Benefits of Active-Matrix LCDs
You may discover that active-matrix LCDs cost more than other types of LCDs. Whether an LCD used TN, IPS or S-IPS technology, it will likely cost more than a passive-matrix LCD. Nonetheless, active-matrix LCDs offer several benefits that make them an attractive choice.
Active-matrix LCDs are typically more responsive than passive-matrix LCDs. Their pixels can respond to new colors more quickly, resulting in faster response times. Passive-matrix LCDs also produce brighter colors than those of passive-matrix LCDs. Not all images will consist of bright colors. For images with bright colors, though, active-matrix LCDs offer a superior level of quality.
