bjiibj wrote:
1. Yes, there are 256 different voltages that can be applied to each subpixel, each voltage causing more crystals to rotate, each voltage thus resulting in a different opacity for that cell.
2. Even IPS displays use crystals which rotate when voltage is applied. The topography is different but the basic mechanism is the same.
3. Each cell of an IPS display is a subpixel, and each subpixel has its own electrodes; IPS just puts them in a different layer of the substrate than TN does.
This will be my last post of this discussion. I really can't be bothered to continue to try to describe to you how LCD panels work. You may find this page elucidating:
http://www.tftcentral.co.uk/articles/panel_technologies.htm
You will note that the backlight is never even mentioned in technical descriptions of how individual colors and brightnesses for each pixel are achieved.
1. WRONG: from your own document:
When voltage is applied to a cell, the crystals of that cell all make a 90-degrees turn. By the way, an IPS panel lets the backlight pass through in its active state and shutters it in its passive state (when no voltage is applied), so if a thin-film transistor crashes, the corresponding pixel will always remain black, unlike with TN matrices.
IPS cells are either ON or OFF ONLY Like I said it, there are NO diferent levels of "twists".
2. The mechanism is not the same when compared to what you have said before, when you implied and yet again on the third item that more than two electrodes were present per pixel, again this is wrong.
3. WRONG, there are only 2 electrodes PER PIXEL, not subpixel. and IPS does not put electrodes in a different substrate, and you can even find this explicitly explained in the document you posted, and you can even find a few graphics there where it is more than crystal clear that the IPS crystal doesn't even twist, it simply turns - It is not a TWISTED crystal from like TWISTED Nematic - and the there is also a few graphics where you can see the subpixels between the 2 electrodes.
IPS matrices differ from TN Film panels NOT ONLY in the structure of the crystals, but also in the placement of the electrodes – both electrodes are on ONE WAFER and take more space than electrodes of TN matrices. This leads to a lower contrast and brightness of the matrix.
BTW, lower contrast = less shades.
The shades (therefore different colors) are achieved based on the orientation of the IPS cells (and combination of the orientation of the subpixels in the same cell (on or off)) and the intensity and frequency of the lit LEDs.
The other method is Frame-Rate-Control (FRC), also referred to sometimes as temporal dithering. This works by combining four colour frames as a sequence in time, resulting in perceived mixture. In basic terms, it involves FLASHING between two colour tones rapidly to give the impression of a third tone, not normally available in the palette. This allows a total of 16.2 reproducible million colors.
From wikipedia:
LED backlights are often dimmed by applying pulse-width modulation to the supply current, switching the backlight off and on again like a fast strobe light.
The interesting part of all this, is that by dimming a White LED (the case here) you can make it turn blue or yellow by increasing its intensity (the pink and yellow shift a few are experiencing and like I said before - many posts before actually - could related to an energy supply configuration.)
QUOTING YOU:
I really can't be bothered to continue to try to describe to you how LCD panels work. You may find this page elucidating:
Yeah right, the page is very educating it is a shame you haven't read it... About the patronization (ONCE AGAIN), so you are trying to look wise by just looking (actually overlooking) for information in a on-demand basis... you don't even understand how IPS works and a few posts back didn't even know what kind of display was being used here...
