Key Difference: TFT (Thin-film transistor) is a type of semiconductor that is used in liquid crystal display (LCD) panels, while plasma displays are developed using noble gases that are electrically heated to produce light. Plasmas are a better choice in producing displays greater than 40 inches, TFT LCDs become more expensive to produce. TFT displays are also thinner, lighter and consume less power compared to Plasmas. Plasmas are also susceptible to burn-ins, where an image that is constantly displayed can be burned on the screen permanently.

TFT (Thin-film transistor) is a type of semiconductor that is used in liquid crystal display (LCD) panels, while plasma displays are developed using noble gases that are electrically heated to produce light. Most TVs today use either one of these technologies.

TFT (Thin-film transistor) is a field-effect transistor that is used to build the LCD screen. A TFT is created by depositing thin films of a semiconductor active layer as well as the dielectric layer and metallic contacts over a supporting substrate. Each pixel of a LCD receives a transistor that makes switching it on and off very easy. Also since the TFT are embedded within the panel itself, it reduces the crosstalk between pixels, like in plasma. Crosstalk is when a signal transmitted to one pixel also affects another pixel. A TFT is also known as an active matrix display technology, which is more responsive to change and has a faster refresh rate. The faster response rate also eliminated the problem faced by gamers.

Currently, TFTs have become the standard in producing LCD and LED screens. TFT uses four types of technologies:  Twisted Nematic + Film (TN Film), In-Plane Switching (IPS), Vertical Alignment (VA), and Plane to Line Switching (PLS). TN Film is the most common of these due to low production costs, but comes with certain drawbacks such as poor depth quality and restrictive viewing angles. TN Film panels provide fast refresh rates and are based around a 6-bit color depth along with a Frame Rate Control (FRC). IPS dubbed as the ‘super TFT’ was created to remove the drawbacks of TN Film. While it improved viewing angles, it provided poor response times, contrast ratios and was expensive to produce. VA displays were originally poor in response times, but offer 8-bit color depth and a great static contrast ratio. PLS is a new display technology created by Samsung in 2011 and offers improved viewing angles, low production costs, better image quality and increased brightness.

Plasmas are more common in displays greater than 40 inches. A plasma panel has tiny cells of noble gases (neon and xenon) and a small amount of mercury in compartmentalized spaces between two glass panels. The panels also have two electrodes between the glass panels, an address electrode and the display electrodes. The display electrodes are surrounded by an insulating dielectric material and covered by a magnesium oxide protective layer. In order to create the pixels, the address electrode and the display electrodes are charged, which then releases an electric current that flows through the cell. The charge stimulates the gas atoms in the cells to release ultraviolet photons. The photons interact with the phosphor material on the cell walls and give off light, creating a visible light photon. Each pixel has three subpixels, one coated with red, one with blue and one with green. By manipulating the intensity of the current, the system can produce hundreds of different combinations of the three colors and creates an image on the screen.

Both technologies have various advantages and disadvantages. While, Plasmas are a better choice in producing displays greater than 40 inches, TFT LCDs become more expensive to produce. TFT displays are also thinner, lighter and consume less power compared to Plasmas. Plasmas are also susceptible to burn-ins, where an image that is constantly displayed can be burned on the screen permanently.

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