Does 100Hz or 200Hz improve the picture on Plasma or LCD Tv?
Tuesday, November 11th, 2008Introduction to 50hz televisions
Ordinarily PAL televisions will refresh the picture with a frequency of 50 Frames Per Second (FPS).The Frames Per Second (FPS) are the number of frames required to generate the illusion of motion. On a 50 FPS (50Hz) Cathode Ray Television (CRT), due to the picture being produced with an electron scan, there is a visible flicker that is seen by the human eye.
The Human eye is at occasionally sensitive to this frequency depending on the intensity of darkness, the speed of the image, and the degree of brightness thus you will occasionally notice the picture flicker on a 50Hz TV. The flicker becomes more apparent on larger screen.
Early 100 hertz technology
Originally 100hz (100 FPS) televisions operated at double the Frames Per Second by creating a duplicate of each frame and inserting it after the original one. By doubling the frequency of the scan to 100Hz and inserting a replica frame this effect was eliminated as far the human eye perceives it. The effect of this is to significantly reduce the flicker.
How does 100hz work on LCD and Plasma Tv ?
Plasma and LCD televisions dont produce flicker since they dont generate the picture with a scan. LCD TVs still benefit from 100FPS because sophisticated digital circuitry creates an additional frame or middle image. This is done by the TV creating an extra frame by means of complex motion compensation as well as interpolation calculations to calculate what the extra fields and frames look like rather than inserting a duplicate frame. (i.e. the first and second frames are different).
However even at 100 FPS the picture still does not deliver a entirely smooth picture particularly with fast motion images. Some television manufactures attempt to reduce this further by employing digital picture processing. Typically there is still a little blurring on quick moving images but the benefits are clearer and better-defined surfaces, sharper pictures, and smoother movement than is possible from 50 Frames Per Second Plasma and LCD televisions.
i.e. if a football moves ten pixels from right to left between frames one, two and three, the 100 Frames Per Second television will digitally create two added frames between one and two, along with two and three, in which the ball will travel five pixels. This therefore results in a total of five frames in which the ball moves a total of ten pixels i.e. the original frames one, two and three plus the digitally created frames that are inserted in between one and two, and between two and three. The eye thus sees a picture that moves more fluidly than before.
100hz improves the picture
100Hz televisions have the clear benefit of eliminating a lot of the ghosting effects occasionally seen in LCD TVs. Ghosting effects caused by the next image being shown before the earlier one has faded away. Even on Plasma tv the creation of the middle frame results in a more fluid picture
Most top manufacturers have now got 100Hz LCD and Plasma televisions including Panasonic, JVC, Samsung, Toshiba, LG, Sony, Philips, Pioneer and Hitachi.
Sony lead the way into 200Hz
A range of 200hz TVs have been produced by Sony which digitally inserts three further frames between the original 50Hz frames. Hence speedy moving sequences are delivered with a more fluid, sharper and smoother picture than 50 hertz or even 100 hertz TVs.
Reduced seizures for people who have photosensitive epilepsies
Research has proven that 100 hertz televisions can assist in preventing seizures in people who suffer with photosensitive epilepsies when viewing television or playing computer games.