Samsung going stratospheric with 480Hz TV?
The Web is alive with rumours that Sth Korea TV-maker and electronics giant Samsung is about to unveil a 480Hz set (or 400Hz in the US, where 50 Hz electricity is the norm). One report suggests it will be displayed next week at IFA in Berlin. LG showcased a 480Hz LCD at the CES last January. But what possible benefits would a 480Hz unit provide? And why stop at 480 Hz? Why not go 600 Hz? Read on and discover why.
There are a few potential answers to this ever-faster refresh conundrum. The usual response for any over-clocked set is that it reduces judder/motion blur and ‘flicker’. Most LCD (and Plasma) display-makers have been churning out ‘double refresh’ 120 Hz units for some time. The main effect that they are trying to overcome is the 3:2 ‘pulldown’ of frames in movies which were shot at 24 Hz (24 frames per second). If the 24 frames/s movie was shown at 30 frames per second, the movie would end up being sped up by about 1.25 times normal speed. To prevent this, the TV actually plays back each movie frame three times in succession, and every other frame twice in succession, hence 3:2 pulldown.
“The problem occurs when a camera pans across a scene. Each frame consists of two video fields. But since each movie frame is displayed three times, there will be two instances where data is taken from the first and second frame, which creates a blurry, motion artefact known as judder,” says Mark Hachman from Extreme Tech. “Displaying images at [double] 60 frames per second, or 120 Hz, eliminates the problem. ‘120’ is five times 24, which means that 3:2 pulldown does not have to be used, and the judder is eliminated,” he adds.
LG, and now seemingly Samsung, in cranking up the refresh rate, are further eliminating the ‘judder’ effect.
But there’s possibly another benefit – and that’s to pave the way for 3D. It is suspected that Panasonic – perhaps amongst others – is seeking the Holy Grail of 600 Hz refresh rates, ten-times the old CRT standard, in order to create room for 3D transmissions that might well depend on what would then be quite spectacular ‘Full 3D’ with 120 Hz for each eye, and double refreshing even that high speed and ultra-low screen response time.
Everyone recognises that full resolution 3D (not the ‘Half 3D’ being currently proposed) needs to handle not only lots of incoming data but a refresh rate on Plasma TVs that eliminates all Judder and Flicker even when 3D, at 120 Hz x 2 channels, is being watched. The consensus seems to be that Samsung’s (and LGs) 480 Hz is not just the ideal refresh rate but in fact is the minimum. So, our advice? Stand by for 600 Hz units, with a response time of just 0.001 milliseconds (ms), a frame sequential possibility, and with a Viera brand on the front panel.