Wednesday, November 27, 2013

Mechanism Behind TFT Monitor

As we know that the TFT LCD Display is the ultimatum, this TFT monitor uses thin film transistor technology. In the olden days, cathode ray tubes were used, but now it is replaced by LCD monitors that has another name, flat panel displays. The abbreviation could be explained as Thin Film Transistor or Liquid Crystal Display.
The advantage of this system has been dealt in many devices. Some of the examples are television, mobile phones, computer monitors, navigator systems, projectors etc. In the calculator which has a small liquid crystal display, the voltage could be applied without the interference of the other segment. But this becomes impossible when the display is large like television or computer monitors.
In such a case, the pixel elements are arranged in rows and columns which reduce the number of connections from millions to thousands. The rows could be driven with a positive voltage and vice versa with the column. Even then, there is another problem. The intersection points or pixels will be driven with higher voltages. The intersection segments tend to be darker. This could be dealt with supplying each pixel with its own transistor.
The pixel is made of a capacitor with the layer of insulating material which is inserted between conductive layers. Plasma Enhanced Chemical Vapor Deposition is the process used for the deposition of silicon. Though TFT monitors and IPS LCD panel are used inter-changeably, there exists some difference. LCD is a device which uses any number of color pixels arrayed in front of light source. The electric power used is very less when compared to TFT monitors. LCD uses flat panels where as TFT uses both flat panel displays as well as projectors. TFT monitors are commonly available in sizes 12 to 30 inches.
There are different types of TFT monitors. They are Twisted Nematics display, In-plane switching, Multi-domain vertical alignment, Patterned vertical alignment and advanced super-view. The most common one is Twisted Nematics display which is inexpensive.
The TFT monitor can be called as active matrix LCD. Though this is not the only active matrix LCD, it is the commonest one. There are also passive Lilliput 7-inch lcd monitor is used in calculators and other small devices. The active matrix-LCDs have the best resolutions and the maximum color display. Now let us look for the commonest type of TFT monitors, Twisted Nematics display type. The best part of this type is the fast response of its pixels. It also uses the method of Frame Rate Control, which causes the simulation of pixels in cycles to provide the needed shade.
The negative part of this type is the poor viewing angle and poor color reproduction which is replaced by In-plane switching. As the name suggests that the crystal molecules move perpendicular to the panel which paves the way to get good color reproduction as well as wide viewing angles. Initially the response was slow but later it was somewhat modified by some new evolutions.
The next type of the TFT monitor is Multi Domain Vertical Alignment which satisfied the color reproduction, wide viewing and also the fast response. But this was overtaken by the inexpensive Twisted Nematics display type. The patterned vertical alignment also uses modernized CRT technologies. The next type is the advanced super view, as the name suggests that it provides wide viewing angle. Even-though there are different types of monitors, the Twisted Nematics type stands the commonest due to its inexpensiveness and the fast response.
The current usage by TFT monitors is very much less when compared to the usual CRT monitors, since this can allow very fast re-drawing of the display as the image is refreshed of repainted many number of times per second.

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