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LG OLED vs Samsung Super OLED - Page 2

post #31 of 179
Quote:
Originally Posted by ferro View Post

This states that it uses White OLED (WOLED) which produce white light and only the white-light product is visible. Without color-filters such a TV can only produce a black & white image.

LG's easy-to-produce stacked red, green and blue OLED's all receive the same current, and therefore can only produce white light, unlike the color-tunable LED's of your linked paper, where each red, green and blue LED can receive a different current.

I think your original point was that a stacked arrangement wasn't used, but that LG used white OLEDs.

Regarding your new point about whether the OLEDs in the stack can receive different currents, I do not presently know. My guess is that LG's WOLED has more similarities to SLED than differences.

Anyway, here's another interesting read:
http://www.oled-display.net/backgrou...tv-technology/

Also, given that the end product of SLED is white, color filters have to be applied with that design as well.
post #32 of 179
Quote:
Originally Posted by taichi4 View Post

I think your original point was that a stacked arrangement wasn't used, but that LG used white OLEDs.

Regarding your new point about whether the OLEDs in the stack can receive different currents, I do not presently know. My guess is that LG's WOLED has more similarities to SLED than differences.

Anyway, here's another interesting read:
http://www.oled-display.net/backgrou...tv-technology/

I was arguing your point that LG's subpixels are color-tunable (like in your linked white paper) and therefore would not need color-filters, but looking back that may not have been your point at all.
post #33 of 179
Quote:
Originally Posted by Nielo TM View Post

Even with White LED, uneven again is a problem

You would think so, and I would agree with you, but I read things like this on Kodak's web site:

Quote:
Originally Posted by Kodak View Post

One of the concerns for OLED technology has been the lifetime of the blue color, which has historically been less than red and green. Over time, this results in very dim blue pixels and shifting of the display toward yellow. Kodak has been developing new architectures to overcome this issue, in particular a very stable White OLED formulation, which can be used in combination with a color filter array to produce a full-color display. Kodak’s White OLED architecture boasts a lifetime in excess of 100,000 hours. There are 8,766 hours in a year, so these devices are very stable. Another advantage of the White OLED approach is the elimination color shift over time due to one color dying out more quickly than the others.

LG purchased Kodak's OLED business as you probably know.

If these claims are true, and if LG is using these technologies, then their OLED TV's could potentially have a lifetime of more than 100.000 hours without any color shift. But to be honest, I can't quite understand it.

Not sure how this relates to Samsungs implementation.
post #34 of 179
Quote:
Originally Posted by ferro View Post

I was arguing your point that LG's subpixels are color-tunable (like in your linked white paper) and therefore would not need color-filters, but looking back that may not have been your point at all.

Right. That wasn't my point. My post was mainly concerning the general concept and advantages of a stacked design vs horizontally arranged LEDs or OLEDs.

It will be interesting to get more info on LG's WOLED design.
post #35 of 179
Quote:
Originally Posted by taichi4 View Post

I don't believe that says it all. Until I find the LG article with a diagram showing the stacked arrangement, this should suffice:

..."LG has also opted for the use of White OLEDs (WOLED), which produce a white-light from red, green and blue diodes vertically, meaning that they are stacked and so only the end white-light product is visible."...

http://hexus.net/ce/news/audio-visua...hdtv-ces-2012/

This may be the diagram that you are looking for.

http://www.oled-display.net/backgrou...tv-technology/
post #36 of 179
Quote:
Originally Posted by greenland View Post

This may be the diagram that you are looking for.

http://www.oled-display.net/backgrou...tv-technology/

No. That's the same diagram and article, although from a different website, as the one posted above. There's another one that is more illustrative of the design, but I can't put my hands on it right now.

But thanks for posting another picture of that lovely LG model standing next to the TV. Let's see what kind of model Samsung can produce for its Super OLED.
post #37 of 179
Ya that's not stacked design. RGB pixels are horozintally placed. In order to stack, you'll need true RGB OLEDs.


http://www.universaldisplay.com/defa...?contentID=610

http://spectrum.ieee.org/semiconduct...-electronics/4
post #38 of 179
Quote:
Originally Posted by specuvestor View Post

Thanks I've heard good things about the film too.

But in all honesty I heard the NASA story more than 20 years ago

http://www.snopes.com/business/genius/spacepen.asp
post #39 of 179
Lol ¬
post #40 of 179
Well,considering info about LG - being regular "Smart TV" vs Samsung - "Genius TV " -( face recognition,gesture and voice controlled). Higher cost of it's 3D glasses and materials ( twice as thick ) ,likely -much more limited quantities produced... -I would say LG's WOLED even besides panels difference should be a relative bargain!
post #41 of 179
"Another advantage of the White OLED approach is the elimination color shift over time due to one color dying out more quickly than the others."

That's just not true. I have no idea why Kodak would post that as it's wrong if any of the sub-colors actually has a different lifespan. LG doesn't plan to make white OLED pixels via magic, the white will come from depositing multiple primary color layers to create a composite white. It's true that it won't need patterning, but it still uses R, G and B.

Maybe Kodak posited a theoretical white emitter, but that doesn't currently exist.
post #42 of 179
Bingo. all three white sub-pixels won't remain unifyed for long. Wish there's some data on the actual decay rate
post #43 of 179
Quote:
Originally Posted by rogo View Post

"Another advantage of the White OLED approach is the elimination color shift over time due to one color dying out more quickly than the others."

That's just not true. I have no idea why Kodak would post that as it's wrong if any of the sub-colors actually has a different lifespan. LG doesn't plan to make white OLED pixels via magic, the white will come from depositing multiple primary color layers to create a composite white. It's true that it won't need patterning, but it still uses R, G and B.

Maybe Kodak posited a theoretical white emitter, but that doesn't currently exist.

Lets pretend you're displaying a 80% all white field that's using an even amount each of R,G & B.

If all white OLEDs with RGB color filters are used to produce white they would wear the same over 50,000 hours. As they are all using the same type of emitter for their light source. All of the white OLEDs would wear out at the same rate (well assuming there didn't need to be any white balance done and the color filters work perfect without needing to compensate. Lets ignore that for now).

Individual RGB OLEDs do not wear the same, they use 3 different organic materials for their emitters. Blue will wear out long before green and red over 50,000 hours. And the color of white will drift significantly.

Here' some older 2007 specs I had of OLED wearing to 1/2 brightness. (I wouldn't use these numbers to figure TV wearing rates, who knows what they're using for materials)
Red 150,000 hours
Green 120,000 hours
Blue 60,000 hours

Blue will deteriorate long before red and green. And to compensate you'll have to lower red and green luminance to match.

In regards to LG's white OLEDs... When speaking of conventional LED bulbs what's fascinating is to make a standalone "white" LED they use a blue LED (which also emits light near ultraviolet) that has a mixture of phosphors in it to convert some of the lower blue spectrum energy into higher red and green spectrum. So this blue LED with the phosphor mixture creates a single white LED.

Is there an organic material or another method they can use to create a single white OLED? Unknown to me....
post #44 of 179
The ultimate goal is to get OLED out on the shelves at Best Buy at a price we can afford to pay. What do I care about seeing RGB with my nose against the TV screen??????

Try not to be such a purist. Your comments have little practical value.

DelJ




Quote:
Originally Posted by Nielo TM View Post

Stacked OLED is the ultimate goal since it yields greater gamut and accuracy. It also creates more natural image due to negligible gaps between pixels and the fact that pixels can produce any color without the RGB being visible up close.

But as far as im aware, you'll need actual RGB OLED to stack. If LG managed to achieve this using white with RGB color filter, then yes that is impressive (but I doubt it tbh)
post #45 of 179
LG 55EM9600 OLED, Wins Best Of Show for CES 2012


http://www.cnet.com/best-of-ces/?tag=TOCcarouselMain.0
post #46 of 179
Quote:
Originally Posted by DelJ View Post

The ultimate goal is to get OLED out on the shelves at Best Buy at a price we can afford to pay. What do I care about seeing RGB with my nose against the TV screen??????

Try not to be such a purist. Your comments have little practical value.

DelJ


I care?

We all want OLED ASAP, but that doesn't mean we shouldn’t talk about the tech or its possibilities. This is a AV Science forum after all.
post #47 of 179
Quote:
Originally Posted by SiGGy View Post

Lets pretend you're displaying a 80% all white field that's using an even amount each of R,G & B.

If all white OLEDs with RGB color filters are used to produce white they would wear the same over 50,000 hours. As they are all using the same type of emitter for their light source. All of the white OLEDs would wear out at the same rate (well assuming there didn't need to be any white balance done and the color filters work perfect without needing to compensate. Lets ignore that for now).

True however, each subpixels will alter it light output based on the image displayed. So all three white OLED won't out put the same level of luminance. We are not talking about LCD on top of OLED
post #48 of 179
Quote:
Originally Posted by Nielo TM View Post

True however, each subpixels will alter it light output based on the image displayed. So all three white OLED won't out put the same level of luminance. We are not talking about LCD on top of OLED

If you are correct about that, could they possibly provide the user with tools to shift the image around, to avoid uneven wear, like those provided in Plasma displays, Orbitor etc?
post #49 of 179
Quote:
Originally Posted by rogo View Post

"Another advantage of the White OLED approach is the elimination color shift over time due to one color dying out more quickly than the others."

That's just not true. I have no idea why Kodak would post that as it's wrong if any of the sub-colors actually has a different lifespan. LG doesn't plan to make white OLED pixels via magic, the white will come from depositing multiple primary color layers to create a composite white. It's true that it won't need patterning, but it still uses R, G and B.

Maybe Kodak posited a theoretical white emitter, but that doesn't currently exist.

I am pretty sure that a tandem white OLED, which is what LG is likely using, does do substantially better with differential aging than a RGB display. The emitters are driven at a lower voltage which elongates the lifetimes. The color filters also likely help with this issue.

I also wonder if you are using exactly the same color blue to create the white as in an RGB architecture. A move to a slightly lighter blue can allow for a much longer lifetime.
post #50 of 179
Quote:
Originally Posted by greenland View Post

If you are correct about that, could they possibly provide the user with tools to shift the image around, to avoid uneven wear, like those provided in Plasma displays, Orbitor etc?

Not sure how we can correct that because we are talking about luminance/brightness difference. The Sony 11" is a perfect example of the issue. Maybe that's why LG decided to use the white pixel minimize the difference.

Pixel orbitor doesn't help much as it only shits the image around few pixels. And if Over-Scan is disabled, it causes more problems.
post #51 of 179
Quote:
Originally Posted by greenland View Post

LG 55EM9600 OLED, Wins Best Of Show for CES 2012

http://www.cnet.com/best-of-ces/?tag=TOCcarouselMain.0

Cool.

"You're pretty solid on the Q3 release date?"
"Yeah, absolutely"
post #52 of 179
Quote:
Originally Posted by rogo View Post

"Another advantage of the White OLED approach is the elimination color shift over time due to one color dying out more quickly than the others."

That's just not true. I have no idea why Kodak would post that as it's wrong if any of the sub-colors actually has a different lifespan. LG doesn't plan to make white OLED pixels via magic, the white will come from depositing multiple primary color layers to create a composite white. It's true that it won't need patterning, but it still uses R, G and B.

Maybe Kodak posited a theoretical white emitter, but that doesn't currently exist.

I would not discard the idea too quickly. There is a lot of information about "stable white oled" on the web. Another example can be found in this document:

System considerations for RGBW OLED displays

This is again written by Kodak engineers, and provides a lot of insight into the White RGBW technology used in the LG TV. The relevant paragraphs are as follows:

Quote:


When constructing an OLED display, it is possible for each of the color channels of the display to degrade at different rates. For instance, in OLED displays formed from patterned red, green, and blue emitters, it is known that differences in efficiencies of the emitters, the stability of the emitters, and the color of the emitters, relative to the display white point, can produce differences in the rate of aging (i.e., the loss of luminance efficiency) of one color channel compared to a second. If one color channel ages significantly faster than the others, the color balance of the display will change with time, and images displayed using a large fraction of the least stable channel will be significantly lower in luminance than desired. [...]

The fact that the efficiencies and stability of the subpixels in an OLED display formed from a single white emitter with color filters will be nearly identical reduces the severity of this problem. However, in RGBW OLED displays, the white subpixel will be significantly higher in efficiency than the red, green, and blue subpixels and, depending on the color-conversion algorithm, may be used much more frequently than the colored subpixels.
post #53 of 179
Quote:
Originally Posted by Nielo TM View Post

True however, each subpixels will alter it light output based on the image displayed. So all three white OLED won't out put the same level of luminance. We are not talking about LCD on top of OLED

With all of the tech info I posted you believe I don't know the difference between the two? :whyme:

all the same...

The point I believe you missed and seem to still be missing is with LG's design each sub-pixel is on equal grounds in terms of life.

With Samsung's they're not on equal grounds. The blue sub-pixel will wear out faster than red and green regardless. In fact Samsung has patents which have algorithms that to try and compensate for this over the life of the panel.

Surely we could spark off a conversation discussing which of the primaries are used the most on average and will dictate higher wear on those sub-pixels. And move on into humans see mostly shades of green and how green is on average 50% of the signal... blah blah.

Reality is you want all of the sub pixels to have the best longevity and stability as possible with the least amount of skew. The blue sub-pixel will start to destabilize 1st on the Samsung TV and they'll either have to compensate for it in their driving software or you will be re-calibrating your TV more often.

I'd prefer whatever produces more stable sub-pixels myself Once blue can achieve 100,000+ hours this will be a moot point. But until then this is an issue.

Don't misunderstand me, there are caveats to both designs which effect performance on different metrics. A lot of this won't be known until they're out and have lots of hours on them. RGB filters are anything but efficient I mentioned the white led tech info purposely to allude to another possible issue. If they are indeed using a blue OLED with a phosphor mix to create the white OLED, the LG panel itself may have an interesting lifespan.

Anyway, without insider knowledge we're at best guessing. Who knows maybe Samsung has a 80-100k blue OLED
post #54 of 179
Quote:
Originally Posted by slacker711 View Post

I am pretty sure that a tandem white OLED, which is what LG is likely using, does do substantially better with differential aging than a RGB display. The emitters are driven at a lower voltage which elongates the lifetimes. The color filters also likely help with this issue.
...

That's an excellent point. From what I've read WOLED more efficiently produces a brighter white output, with less leakage...so less of a need to drive the OLEDs.
post #55 of 179
Actually I do and Sony did the same minus the additional white pixel. Having all white means they will all age at the rate providing the all three subpixels are active and producing identical level of luminance.

However, we still have no info based on real world performance. The Sony 11 couldn't even last a year
post #56 of 179
Quote:
Originally Posted by taichi4 View Post

That's an excellent point. From what I've read WOLED more efficiently produces a brighter white output, with less leakage...so less of a need to drive the OLEDS.

But its softens the image. damned if you do and damned if you don't lol
post #57 of 179
Quote:
Originally Posted by Nielo TM View Post

But its softens the image. damned if you do and damned if you don't lol

How does it do that?
post #58 of 179
RGBW concept isn't new and it prime purpose is to cut power consumption. The extra pixel softens the edge.


PenTile (RGBW) top, RGB bottom

http://www.talkandroid.com/wp-conten...een.jpg?3995d3
post #59 of 179
Quote:
Originally Posted by Nielo TM View Post

RGBW concept isn't new and it prime purpose is to cut power consumption. The extra pixel softens the edge.


PenTile (RGBW) top, RGB bottom

http://www.talkandroid.com/wp-conten...een.jpg?3995d3

Interesting. I can see how the subpixels are oriented different.

However, I'm wondering if this is a controlled comparison. Seems like the focus is off on the top one a bit and it's not oriented completely to the camera. When taking macro shots that close you'd have to be dead on.

Any idea if those were both taken with the same camera and macro lens?
post #60 of 179
Quote:
Originally Posted by Nielo TM View Post

It's funny how LG justifies using the white pixel. they might as well say our panel isn't as advanced as the Samsung but we are trying.

Define 'advanced'? In this context what does that get you besides cost? Obviously at this point we don't know which performs better, but let's assume they're similar overall.

The rationale behind LG's design is lower costs, higher efficiency, and a longer life (including without color shift). If anything, one could argue LG's design is more advanced. Isn't Samsung's design just an extension of their current RGB AMOLED design? Wouldn't that be considered conventional instead of advanced?
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