Plasma is dead: IPS LCD with black level of 0!

Pastuch

Gawd
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http://www.digitalversus.com/lg-47lex8-p364_10173_35.html

LG 47LEX8

The LEX8 is the best TV we've ever tested: the combination of an IPS display with 2160 separate LEDs produces spectacular results, with black levels so deep that they were off the scale, dynamic contrast that we're happy to recommend for once and the whole thing in a frame measuring just 8.8 mm from front to back.

It's non-reflective too! Epic!

Holy shit put this technology into a computer monitor! NOW!
 
LED Local Dimming... Move along, nothing to see here.

It's bearable for watching movies but not as a computer monitor.

1920x1080 with 2160 led domains would make each led domain roughly 30x30 pixels in size. Needs to be way smaller in order to be decent as a PC monitor.
 
So it's basically a LED backlit TV with local dimming and a big amount of "zones". That's not going to work for a computer display, is it? Wish they would have taken some measurements with dynamic contrast off.
 
Nothing over 24" will ever be good as a computer monitor unless the resolution is upped.
 
Sounds like it would be a pretty cool computer display, if one has the furniture and space to accomodate such a beast (would want to push it back farther). And if it has a full color resolution/RGB mode, which is apparently an issue now with some TVs.

Not a perfect monitor, but that makes it just like every other tech out there in that regard...local dimming should help it nail a couple of the basics though...
 
Yeah I hated my LG 20" which had that stupid "shut off the backlight" trick to make blacks looks blacker.


Except it was always a bit off the mark on timing. So it was annoying to watch.
 
LED Local Dimming... Move along, nothing to see here.

It's bearable for watching movies but not as a computer monitor.

1920x1080 with 2160 led domains would make each led domain roughly 30x30 pixels in size. Needs to be way smaller in order to be decent as a PC monitor.

You talk as if people regularly use 47inch screens as a monitor instead of a tv.:rolleyes::p
 
So it's basically a LED backlit TV with local dimming and a big amount of "zones". That's not going to work for a computer display, is it?
Yes, especially for everything that affects CEPS because gradation is dependent on visual content with that kind of dynamic backlighting.

Best regards

Denis
 
Local dimming would require post processing to determine local brightness right? No go if I need minimum input lag, though a uniform LED backlight would be better than edge lit.
 
Stupid question perhaps, but now that we're talking LEDs - isn't it economically and physically possible to produce LEDs in a say 0.26 mm x 0.26 mm square size in red, green and blue - then line them up, and adress these like if they were transistors? Or is the problem that they need a variable resistance, for each LED in order to limit current and thus control brightness?
 
Stupid question perhaps, but now that we're talking LEDs - isn't it economically and physically possible to produce LEDs in a say 0.26 mm x 0.26 mm square size in red, green and blue - then line them up, and adress these like if they were transistors? Or is the problem that they need a variable resistance, for each LED in order to limit current and thus control brightness?

FWIR, depositing an LED semiconductor by epitaxy requires high temperatures and precise cooling. It looks like it isn't possible to produce an LED array below certain dimensions.
 
One word: Halos

Plasma:
localdimming01md.jpg


LED - Local Dimming (LD) LCD:
localdimming02md.jpg


This might be OK with most video feeds with generally soft transitions, but in a monitor that you are sitting close to, where your desktop is full of sharp transitions, Halos would drive most people nuts.

This isn't new technology, they have doing this for years, but it was never done for a computer monitor and it likely never will be. It would be very expensive and the artifacts would be very annoying. As I submit this I am on a black page with tiny white writing, they would surrounded in halos on an LD set.
 
Different LED colors require different materials to be used to achieve the required bandgap for the electroluminiscence. AFAIK, it is impossible to produce a RGB matrix, as applying a specific color would degrade the material of the last applied color to much. Because of this, discrete RGB LEDs comprise three separate LEDs with different colors.

What you describe is achieved by OLED technology, but it is still expensive.
 
And OLED degrade with usage. So having one act as a backlight is not going to happen - yet.
 
Nothing over 24" will ever be good as a computer monitor unless the resolution is upped.

Pretty much my conclusion after using various 32", 37", and 42" 1920x1080 panels. Even 27" at 1080p is stretching it up close.

As for text quality or input lag on most tv sets, that's an entirely different debate. :)
 
Good effort for TVs for sure (is this where I make a smug comment about CRTs and perfect blacks?), but not quite suitable for computer monitors.

If someone can convince the world to stop settling for LCDs, maybe FED and SED research will be revived and ready in a decade :(
 
Different LED colors require different materials to be used to achieve the required bandgap for the electroluminiscence. AFAIK, it is impossible to produce a RGB matrix, as applying a specific color would degrade the material of the last applied color to much. Because of this, discrete RGB LEDs comprise three separate LEDs with different colors.

What you describe is achieved by OLED technology, but it is still expensive.

Theoretically you can achieve the same result with white LED + colour filters. As you said, different LED colours require different materials, each with different parameters such as temperature for deposition. I can't conceive of any method to produce a high pixel density LED display, colour filter or not.
 
If someone can convince the world to stop settling for LCDs, maybe FED and SED research will be revived and ready in a decade

Field emission displays are dead. It is a viable technology, but OLED has just so much exciting potential to change not just the display market, but the whole of lighting and digital signage. There is nothing really beyond OLED, especially considering transparent OLED devices.
 
It's too bad we still don't have truly universal and established standards in the industry where contrast ratio numbers and other specs like that as it relates to displays would actually mean something.
 
FWIR, depositing an LED semiconductor by epitaxy requires high temperatures and precise cooling. It looks like it isn't possible to produce an LED array below certain dimensions.
Ah, interesting! I noticed the smallest LED is approximately 1 mm and called picoLED. But yes, cooling surface (and hence the power draw) seems to be a major problem - and the efficiency would be too low in comparison to LCD or OLED to be suitable.
 
Take a look at QLED.

Adam

I am already aware of QDLED. The design shares some features with OLED. It will be interesting to see if QDLED can win over OLED for lighting in efficiency and CRI as well as deliver proper blue saturation for displays. Both technologies should be capable of transparent designs. In any case, market growth for OLED is already being forecast beyond 2028.
 
QLED is only a minor enhancement on OLED. We are years from OLED TVs, and QLEDs are years behind OLED. They also have organic components and degrade, they also have trouble with blue. Possible even more problem than OLED with blue because there is a quantum limit on blue quantum effect.

OLED is the big one because it is will give perfect blacks, QLEDs might eventually come along, but their main advantage will efficiency improvements.

I think it is fairly safe bet you won't see QLED monitors/TVs for ten years.
 
QLED is only a minor enhancement on OLED. We are years from OLED TVs, and QLEDs are years behind OLED. They also have organic components and degrade, they also have trouble with blue. Possible even more problem than OLED with blue because there is a quantum limit on blue quantum effect.

Just a note that QDLED is based on metal alloys and not organic compounds like OLED.

A further note, the issue with Blue in OLED is the half-life. The practicle issue with QDLED is the challenge of developing a blue material that is both efficient and correctly saturated.
 
You will notice most of the QD hype stories don't mention lifetimes...

http://www.technologyreview.com/computing/26831/page2/
"Coe-Sullivan is hesitant to provide a solid time line for QLED manufacturing. Since QD Vision was founded, the company has made strides, thanks to tweaks in chemistry and engineering, that have improved the length of time that electroluminescent quantum dots can shine. But currently, the best QLEDs have a lifetime of 10,000 hours—not long enough for a large display"

Sound familiar? They are at least 5-10 years behind OLED.
 
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OLED is the big one because it is will give perfect blacks, QLEDs might eventually come along, but their main advantage will efficiency improvements.

IMHO the main advantage is screen size with QLED over OLED. QLEDs don't require shadow masks to manufacture, OLEDS do. Shadow masks can be a serious problem with large screens.
 
You will notice most of the QD hype stories don't mention lifetimes... the best QLEDs have a lifetime of 10,000 hours—not long enough for a large display"

Sound familiar? They are at least 5-10 years behind OLED.

I can give you a quote of 50,000 hours from http://www.photonics.com/Article.aspx?AID=37034

Frankly I think these lifetime numbers are worthless unless I read it in a publication or SPIE.org
 
I can give you a quote of 50,000 hours from http://www.photonics.com/Article.aspx?AID=37034

Frankly I think these lifetime numbers are worthless unless I read it in a publication or SPIE.org

That 50,000 hour quote is a vague reference to light bulb replacement (where you can use a high volume of QDs to last a long time), not tiny RGB pixels in a display. My quote is from an interview yesterday, with the QD company at the center of current display work and partnering with LG.

If the leading QD display company says they are only at 10 000 hours on the best display tech now (being yesterday) this is the most optimistic result for displays. He also is hesitant to put forth a time-line and can just see commercialization on the horizon. OLED was commercialized years ago.

They are at minimum 5 years behind OLED, more like 10 years.
 
That 50,000 hour quote is a vague reference to light bulb replacement (where you can use a high volume of QDs to last a long time), not tiny RGB pixels in a display. My quote is from an interview yesterday, with the QD company at the center of current display work and partnering with LG.

If the leading QD display company says they are only at 10 000 hours on the best display tech now (being yesterday) this is the most optimistic result for displays. He also is hesitant to put forth a time-line and can just see commercialization on the horizon. OLED was commercialized years ago.

They are at minimum 5 years behind OLED, more like 10 years.

QD Vision actually cites their QD lighting product as 50,000 hours, so I think QD Vision is pretty much the only source for life time figures. If the 10,000 hr estimate is accurate, then I want to know how QDLED degrades and whether it is similar to OLED degradation. I can't seem to get a proper answer except hints to impurity fluorescence quenching, just like in OLED.
 
Impressive display , the haloing effect of local dimming LED sets is annoying as hell though but only on extremely dark scenes (which is rare) so I don't think its a deal breaker for most people (not super picky avsforum users though).
 
QD Vision actually cites their QD lighting product as 50,000 hours, so I think QD Vision is pretty much the only source for life time figures. If the 10,000 hr estimate is accurate, then I want to know how QDLED degrades and whether it is similar to OLED degradation. I can't seem to get a proper answer except hints to impurity fluorescence quenching, just like in OLED.

A light bulb is not a Display. Also their light-bubs are are based on putting quantum dot film, in front of conventional LED light source, which converts some blue output of the regular LEDs into more usable light. Very neat stuff, but isn't how the displays will work. It isn't an actual QD-LED that will emit light when fed power. It is a filter than changes one color light to another very efficiently. So it's lifespan doesn't translate.
http://www.qdvision.com/quantum-light-optic

QD Vision is the same company where the 10K hour claim for their best display life, which is a different tech.

I have no answer on where the degradation comes from either, but it should be clear they are fair bit behind OLED display technology.

The breakthrough OLED needs now for large screens is something like this(OLED printer tech):
http://www.technologyreview.com/computing/24520/

I think projections for a practical OLED TV is something like 2015-2016. Tack on a few more years for QD-LED.
 
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Yawn. I have still to see a tv, ANY TV that matches my Pionneer Kuro Krp500M in PQ in anyway :confused:

Give us that 50inch Oled already
 
Pretty much my conclusion after using various 32", 37", and 42" 1920x1080 panels. Even 27" at 1080p is stretching it up close.

As for text quality or input lag on most tv sets, that's an entirely different debate. :)

I regularly use my 112 inch Benq W5000 DLP 1080P projector as a computer monitor. No complaints. I also use if for gaming and the input lag is a little annoying but not too mad. Ghosting is very minimal.
 
Geez where has digitalversus been? local dimming isnt a new technology and comes with side effects vs. say, a Plasma with true black levels (being they don't have to rely on any special tricks to achieve a deep black).
 
Geez where has digitalversus been? local dimming isnt a new technology and comes with side effects vs. say, a Plasma with true black levels (being they don't have to rely on any special tricks to achieve a deep black).

Well, arguably, you are correct. However, by using the direct illumination of individual phosphors, eschewing illumination by a proper array of light bulbs or LEDs, isn't plasma cheating?
 
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