Home > Active-matrix liquid crystal display

An AMLCD (also known as active-matrix liquid crystal display) is a type of flat panel display, currently the overwhelming choice of notebook computer manufacturers, due to light weight, very good image quality, wide color gamut, and response time.

The most common example of an active matrix display contains, besides the polarising sheets and cells of liquid crystal, a matrix of thin-film transistors (TFTs). These devices store the electrical state of each pixel on the display while all the other pixels are being updated. This method provides a much brighter, sharper display than a passive matrix of the same size. An important specification for these displays is their viewing-angle.

Thin film transistors are mandatory for constructing an active matrix to the point where the two terms are often interchanged, even though a thin film transistor is just one component in an active matrix. Whereas a passive matrix display uses a simple conductive grid to deliver current to the liquid crystals in the target area, an active matrix display uses a grid of transistors with the ability to hold a charge for a limited period of time (much like a capacitor). Because of the switching action of transistors, only the desired pixel receives a charge, improving image quality over a passive matrix. Furthermore, because of the thin film transistor's ability to hold a charge, the pixel remains active until the next refresh .

What type of display should you get for your laptop? There are seven different types of displays being sold, each type is associated with a specific resolution. The screen resolution signifies the number of dots (pixels) on the entire screen. The higher the resolution, the more dots or pixels and the more viewing space on your desktop. For example, a VGA monitor is the lowest resolution at 640 x 480. This means your desktops icons will appear large at about 1" square and you will see about 1/4 of page in MS Word. Oracle applications were designed for displays set at a resolution of 1024 x 768 (XGA). Getting a high resolution (UGA) screen on your laptop may strain your eyes if you set it to the maximum resolution, making the icons tiny.

Here's seven display types:

See also

• Liquid crystal display