James Freeman wrote:It should be simple enough.
The bigger the better, because it will allow you to hide more of the pixel transition in total darkness,
You will want to find the point on your LCD electronics (e.g. via oscilloscope) where the vertical blanking interval signal is, and use that as a strobe trigger.
Time your LED backlight strobe circuit to flash the backlight towards the end of the blanking interval, preferably partially overlapping the start of next refresh by a fraction of a millisecond
This gives you more time for the pixels to settle in the blanking interval before strobing the basklight.
Good experimentation.HeLLoWorld wrote:Also, there is just no good setting even at 1ms flash, whatever you choose it's either the top or the bottom of the frame, or both, that have ghosting.
Such is 60Hz continuous refresh.
HeLLoWorld wrote:Also, there is just no good setting even at 1ms flash, whatever you choose it's either the top or the bottom of the frame, or both, that have ghosting.
Such is 60Hz continuous refresh.
That's correct.James Freeman wrote:Is the blanking interval is when Nothing Happens, the lcd just waits, "unused time" to let the pixels settle longer?
Yes, but if you use a longer blanking interval, that's a bigger pause between the end of the previous LCD refresh, and the beginning of the next LCD refresh cycle. That's what I mean by creating a bigger pause between LCD refresh cycles.James Freeman wrote:Isn't at the end of the VBlanking a new pixel transition cycle starts?
Not necessarily. Shorter time between refreshes means more time sending voltage to each LCD pixels. Accelerated scanouts (e.g. refreshing a 60Hz refresh in 1/90sec or 1/120sec) to create a longer pause between refreshes (blanking interval) has the same disadvantage of witnessing poorer color quality at 144Hz versus better color quality at 60Hz. But it's a good way to gain more pixel transition settling time.James Freeman wrote:If I have a faster LCD, is a long blanking needed?
Definitely not, the problem is more visible at 120Hz than at 60Hz.HeLLoWorld wrote:Okay, I meant, the fact that the refresh is done continuously (and slowly hence 60Hz as opposed to for example 120 in which case the problem would be less visible)
HeLLoWorld wrote:However I kind of supposed that the top pixels were decaying by the time the bottom pixels are refreshed.Do you mean that when the pixel are refreshed, they take a long time to settle to their assigned value
HeLLoWorld wrote:but that they stay to this value for a long time (far more than a refresh cycle)?
HeLLoWorld wrote:In that case why do the pixel take time to attain their value after being told so
HeLLoWorld wrote:why do they stop at this value
HeLLoWorld wrote:and why do they stay there?
HeLLoWorld wrote: Is this a chemical/physical phenomenon? More about this?
HeLLoWorld wrote:In that case, by waiting far longer after the total refresh, there will indeed be a time where all the picture will be correct, and we can flash, and like you say one can do this by doing a customized longer VBL.
HeLLoWorld wrote:But this will lower the frame rate.
HeLLoWorld wrote:Or, do accelerated scanout like you say, but I don't know if I can do this.
Chief Blur Buster wrote:HeLLoWorld wrote:but that they stay to this value for a long time (far more than a refresh cycle)?
Not necessarily. Watch the high speed videos below.
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