The lines between the pixels

[WiredEarp]

Haha I think we all like to speculate

I know next to nothing about OLEDs - are you sure the panel itself is usually transparent though?

Really, since the issue will be reduced and eventually eliminated by higher resolutions, its more of an intellectual exercise. We had a similar discussion about using lenses to hide bezels on multi screen setups not too long ago.

@ geekmaster: Yep, if you look at the 'LCD' pixel in this representation: http://en.wikipedia.org/wiki/File:Pixel ... _Pengo.jpg you'll see that horizontal stripes look quite feasible.
However, even vertical ones could be done by simply using a general diffuse type layer, and punching holes in the centre of each sub pixel. Basically, its a standard flat diffuse, but with slightly higher transmission due to the holes. I can't see any reason why it would be any WORSE than a basic diffusion layer.

I seem to remember back in the day of massive pixels in HMDs, and required diffusion layers, that there was a diffusion type that had a 'dot' in the centre of each pixel (VPL's design perhaps?). I believe it was supposed to help reduce the SDE and visible pixel size. I'm sure lots and lots of clever types of diffusers were tried out during this period simply out of necessity. These days we can just wait for Rift DevKit V2 or the commercial Rift.

[geekmaster]

@ geekmaster: Yep, if you look at the 'LCD' pixel in this representation: http://en.wikipedia.org/wiki/File:Pixel ... _Pengo.jpg you'll see that horizontal stripes look quite feasible.
However, even vertical ones could be done by simply using a general diffuse type layer, and punching holes in the centre of each sub pixel. Basically, its a standard flat diffuse, but with slightly higher transmission due to the holes. I can't see any reason why it would be any WORSE than a basic diffusion layer.

Except the Rift used an IPS panel where the vertical stripes are only between blue and red, giving nice square pixels.

[OzOnE2k10]

OK, some more speculative ideas then. ...

Got an unsurprising response back from njytouch regarding direct backlight control...

For your question" backlight could be controlled in sync with VSYNC", I think you have high requirement.
For common using, the board is OK and with HDMI function.

Regards,
Maria

- njytouch

Oh well, I tried.

The good news is - I managed to find and download the source code for the Realtek RTD2660/RTD2662 firmware!
So it should now be possible to try doing some mods when my Hydis arrives.

Failing that, I'll just control the backlight PWM signal directly and see what happens.
Hopefully it won't drop the brightness too much.

btw, the source contains many header files for different panels and lots of other goodies.
I just compiled the example (Keil C51 compiler), so just need a programmer cable now.

I'm not sure I can post it on here though? Maybe via PM?

[WiredEarp]

@ geekmaster:

Except the Rift used an IPS panel where the vertical stripes are only between blue and red, giving nice square pixels.

I think we've all pretty much decided that we are mostly discussing hypothetical solutions now - not just the Rift. That said, I still fail to hear how, if a basic diffusion layer will do a basic job, one with partial cutouts of the diffusion material to allow more transmission through the centre of the light element will not produce a better effect, at least in terms of brightness and color. I can personally think of several potential obstacles of course. However, looking at pics of IPS pixels, I don't see that the basic idea would be applied much differently.

@ OzOnE2k10:

I'm not sure I can post it on here though? Maybe via PM?

If its not copyrighted source, just zip/rar it up and upload it as a file to a post?

[OzOnE2k10]

Erm, yeah. It might be a teensy bit Copyrighted.

You can find it with "Realtek 2660 PUDN", but need to upload something before it will let you download.

Then you'll need the Keil C51 compiler. (ahem, cough... bt).
I'll see if I can figure out a very simple programming cable too when the Hydis controller arrives.

If this proves too complex / too much hassle, a simple "mod chip" would do the trick.
(assuming the Rift dev kit still has the Backlight control wire going to the control box, and that a VSYNC signal is freely available.)

I think that's probably about as much as I can say for now.

[realyst2k]

I know next to nothing about OLEDs - are you sure the panel itself is usually transparent though?

Generally, yup. The black backing is actually just attached. Actually, since most manufacturers don't want the pixels to bleed their color(aiming for sharpness) so they use the blackest, dullest material they can find so that it absorbs the pixel's light as much as possible.

However, you can find OLED implementations where they do away with it. Mostly in mirror-surface objects(MP3 players which are reflective except for the text or status indicators or even literal bathroom mirrors which feed you data), but also, in stuff such as lighting when the goal is simply to have it glow out of something clear(as opposed to EL which is opaque)

[OutatimeTV]

There's another thread with "Can someone with a Rift test this ?" but my question is based on the resolution of the Dev Kit display.

I guess the "native" resolution of the 7" is 1280x800 pixel.

Normally you can choose higher resolutions than the native one on TFT/ LCD (by interpolation).
The result will be a not that crisp clear image.

Is it possible to go higher (1638x1024 or more) than the recommended resolution ?
I know that it can't reduce the screendoor effect but maybe the image will look better (subjective impression).

My guess is this will result in much more blur but maybe it looks better?
Can someone confirm this please ? Thank you.

Disclamer: But please do that on your own risk! Don't go higher than 1280x800 if you are scared. It might defect your display.

[geekmaster]

There's another thread with "Can someone with a Rift test this ?" but my question is based on the resolution of the Dev Kit display.

I guess the "native" resolution of the 7" is 1280x800 pixel.

Normally you can choose higher resolutions than the native one on TFT/ LCD (by interpolation).
The result will be a not that crisp clear image.

Is it possible to go higher (1638x1024 or more) than the recommended resolution ?
I know that it can't reduce the screendoor effect but maybe the image will look better (subjective impression).

My guess is this will result in much more blur but maybe it looks better?
Can someone confirm this please ? Thank you.

Disclamer: But please do that on your own risk! Don't go higher than 1280x800 if you are scared. It might defect your display.

I tried feeding my Rift at various resolutions up to 1920x1200 (which it supports). Not only does the tiny rescaler in the Rift controller have FAR LESS computing power than your typical desktop PC, but it actually drops some horizontal lines, AND rescaling in the LCD is known to add an entire frame of latency in many LCD panel controllers (acquire entire frame/rescale/output entire frame). But the really worst problem is that it will HORRIBLY mess up sup-pixel rendering that REQUIRES the display to be used in its native mode (1280x800). Driving it at 1280x768 would still allow colored subpixel alignment, but may either rescale the image (more latency) or add a tiny amount of letterboxing to get it up to 1280x800 inside the LCD controller.

Running the Rift at any resolution OTHER THAN 1280x800 is a VERY BAD IDEA!

Just let the GPU do the rescaling, okay?

[OutatimeTV]

OK, thank you for the detailed infos on your tests.

[GobHoblin]

Excuse me if I'm being ignorant here, but there is an old photography trick for soft focusing that may be useful here. Putting vaseline on a filter with a cotton swab creates a great soft focus effect, and I was wondering if it may help by doing the same thing for the lenses with the rift to alleviate the "screen door" effect.

[Machinima]

Except the Rift used an IPS panel where the vertical stripes are only between blue and red, giving nice square pixels.

Really? an IPS panel? I thought they were notorious for high latency, or have things moved on since I last looked into these things. I remember a few years ago gaming on an IPS was considered worse than on a TN because the higher pixel switching times causing ghosting and such.

[geekmaster]

Except the Rift used an IPS panel where the vertical stripes are only between blue and red, giving nice square pixels.

Really? an IPS panel? I thought they were notorious for high latency, or have things moved on since I last looked into these things. I remember a few years ago gaming on an IPS was considered worse than on a TN because the higher pixel switching times causing ghosting and such.

The pixel structure LOOKS like IPS to me. I do not know the specs for the actual panel used in the Rift Dev Kit. Are they published somewhere?

Whatever LCD technology it uses, the ghosting is not bad, and certainly not as bad as the 5.6-inch panel used in Rift prototypes.