The FFD becomes the overdrive
Whether this idea comes from NEC or not, the fact is that we have found it again under the name of overdrive. This Overdrive also has different names from one manufacturer to another. ViewSonic, who doesn’t build any panels, named it ClearMotiv and explains it like this:
In blue on the above graph, the liquid crystals normal answer when the voltage is applied, is in black on the graph below. This response is slow and represents a slow moving change materialized on the monitor by trails of light (smudge). On the dotted line above, is the crystals’ targeted response time. If they reacted thus, there wouldn’t be any afterglow.
The overdrive, or ClearMotiv here, consists, as the " Input voltage " graphic shows, in applying an overvoltage during a limited amount of time, so as to motivate the crystals a little bit more, then return to normal voltage once the correct orientation is achieved.
If we consider this graph as realistic and accurate (it is extracted from a whitepaper exemplifying this technology), and if we apply the ISO rule of the +10ù and -10% of the signal, the response is 60% faster in this particular case! In practice, the initial 12 ms response time would be reduced to 5 ms.
New measure
The main interest of the Overdrive would be to greatly increase the color changes between greys. On the other hand, in principle, it doesn’t change anything from black to white and the other way around because the voltage applied to these crystals is already the maximum. The manufacturers face another problem. They have on one side panels that are estimated as clearly faster than in the past and an ISO norm that doesn’t allow them to show these increases.
This is why we have seen for more than a year, the release of panels with a response time including a
G2G, or an equivalent (GtoG…). That means that the new measure isn’t "white-black-white" like the ISO norm says, but "grey-grey-grey" (light grey-dark grey-light grey). Manufacturers measure all the response times and communicate the fastest one. It means that a 16ms ISO monitor could be introduced a few weeks later as a 12 ms
G2G.
