|
What is TFT?
Short for thin film transistor, a type of LCD flat-panel display screen, in which each pixel is controlled by from one to four transistors. The TFT technology provides the best resolution of all the flat-panel techniques, TFT screens are also called active-matrix LCDs.
How does TFT work?
In a TFT screen, an extra matrix of transistors is connected to the LCD panel – one transistor for each colour (RGB) of each pixel. These transistors drive the pixels, eliminating at a stroke the problems of ghosting and slow response speed that afflict non-TFT LCDs. The result is screen response times of the order of 50 ms and below, and contrast ratios of 200:1 and above.
The TFT acts as a switch. The gate electrode of TFT is connected to a scan line, the source electrode is connected to data line and the drain electrode is connected to a storage capacitor. When the gate is selected the channel of TFT is open and the image data is written into the storage capacitor. When the gate is unselected, channel of TFT is closed, the voltage at the pixel however is kept until the next data is applied, thanks to the charge released by the storage capacitor.
Click here for TFT Evaluation Kits Details!
The advantages of using TFT
- High Pixel Density: > 100 ppi
- Scalable Resolution: from 128x128 dots to QUXGA
- Crisp colours: high colour saturation, high contrast
- Excellent readability: due to high contrast and wide viewing angle;
- Portrait/Landscape support: by use of symmetric viewing cone
- Multimedia capability: high speed
Applications of TFT technology
Today TFT displays are used in a broad range of devices that require electronic display panel. Among most popular types of application are:
- Communications;
- Industrial;
- Medical;
- Marine;
- Consumer;
- Office equipment;
- White goods;
- Dynamic information displays
|
