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Whatever happened to LED Backlighting on LCD panels?
- Thread starter Karma
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It's going to come on the market this year if it hasn't already. Apparently, Samsung is one of the manufacturers to release a model. Be prepared for a steep price tag, though. They're not going to be sold cheap by any indication.
There are multiple reasons for this:
1. CCFL technology has improved to the point where it can provide a color gamut which is very close to that of the best RGB LED BLU.
2. The other advantages of LED aren't all that significant: somewhat lower power usage, less heat, fast warm-up, no mercury.
3. LED BLU is significantly more expensive than CCFL, mostly because of lower volumes, and that's a chicken-and-the-egg problem when LED doesn't offer a strong advantage to make it worth the higher price.
4. Technical difficulties. It's actually pretty tricky to get an LED BLU to work in a large monitor. There are all kinds of issues such as heat dissipation (LEDs generate less heat than CCFL, but it's very concentrated and it degrades brightness and kills LEDs quickly). That's why LED LCD monitors have a fan. Maintaining brightness and color uniformity and stability is another challenge.
5. Lower brightness. Vendors compete on how bright their monitors are (don't ask me why), and LED BLU is not as bright as current-generation CCFL.
NEC and Samsung have some models on the market, but they aren't cost-effective, and aren't popular.
LED BLU is seeing a little more success in LCD TVs because it enables a high dynamic contrast where the LEDs in dark areas are turned off, but this is irrelevant to computer monitors.
Honestly, I don't see a bright (no pun intended) future for LED BLU in monitors. OLED has a lot more potential to differentiate itself.
One of the reasons I ask is that I was under the impression some big changes were in the pipeline. I didn't want to get a new display and suddenly have it be outdated in a few months.
btw I thought OLED's weren't hitting the 20" & higher level until sometime in 2010+
btw I thought OLED's weren't hitting the 20" & higher level until sometime in 2010+
Well, it doesn't say a whole lot, but I saw THIS little item on TFT Central about some ACER 19 and 22 inch LED's :
http://www.tftcentral.co.uk/news_archive/11.htm#acer_led
http://www.tftcentral.co.uk/news_archive/11.htm#acer_led
Oh joy... a LED backlit TN panel.
Not irrelevent, just very expensive...
The Samsung 81F looked like it would make a great display, but the 80 percent price premium over the traditional model held me off...
From what I've read in reviews of the samsung and nec LED backlit products, LED backlit monitors produce MORE heat and use MORE energy. LED lumen/watt efficiency apparently is not as good as CCFL yet, what you do get is more gamut and longer lifetime. Apparently that is the reason LED backlit pro monitors from samsung and NEC are thick with heavy heatsinking. And the samsung one even has a cooling fan in it. Both draw substantially more power than a CCFL counterpart. I wish I remembered which review I read showed the power readings of it.
As for the laptops, I don't know, maybe it's different kind of LED where color accuracy isn't important but efficiency is. That's probably how they got those in there and working without a huge power consumption and heat penalty.
vick1000
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Yes, LED displays produce more heat. That's why the brighter they get the more cooling they need, as in that huge dynamic LED display that had water cooled LEDs in it (name slips my mind).
Actually, LED BLU consumes LESS power and generates LESS heat than a CCFL backlight. The problem is that with LED the heat is concentrated in each small LED, so the heat is concentrated in many pin-point locations. This is unlike the case with CCFL where the heat is spread over the large area of the CCFL. The heat concentration of LED results in heat dissipation challenges. The problem is not the amount of heat generated (it's less than CCFL), but its concentration.
Menelmarar
Supreme [H]ardness
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It's big in the mobile sector.
I've seen lots of laptop from Dell and I think Lenovo with LED backlight as option to get a thinner laptop.
I've seen lots of laptop from Dell and I think Lenovo with LED backlight as option to get a thinner laptop.
Not really - viewing angles are a property of the LCD panel, not the backlight. Same with contrast ratio other than that LED BLU makes it possible to turn off the backlight dynamically in dark areas to improve contrast, but this is not done in computer monitors, only TVs. Color reproduction can be better, but not significantly better than WG-CCFL.
I do not think that using a LED array is the solution for backlight bleeding.
Backlight bleeding occurs when the light is not 100% blocked (whether the source is CCFL or LED is irrelevant).
LED has a few advantages but it will not save the LCD technology from most of its weaknesses (viewing angles, image blur, input lag, poor black, backlight bleeding, ...)
Samsung uses a dimmer to create perfect black on their 81 series.
However, this technology has a few issues.
1) The LED array is divided into 10*8 zones. Each individual LED is synchronized with the zone it belongs. A problems occurs when there is light and black in one zone.
2) There is a delay before the dimming occurs. Again, the image does not look natural.
IMO, the Pioneer Plasma Kuro looks much better than Samsung's 81.
Backlight bleeding occurs when the light is not 100% blocked (whether the source is CCFL or LED is irrelevant).
LED has a few advantages but it will not save the LCD technology from most of its weaknesses (viewing angles, image blur, input lag, poor black, backlight bleeding, ...)
Samsung uses a dimmer to create perfect black on their 81 series.
However, this technology has a few issues.
1) The LED array is divided into 10*8 zones. Each individual LED is synchronized with the zone it belongs. A problems occurs when there is light and black in one zone.
2) There is a delay before the dimming occurs. Again, the image does not look natural.
IMO, the Pioneer Plasma Kuro looks much better than Samsung's 81.
Michael Daly
[H]ard|Gawd
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Let's be careful not to throw out the entire technology on the basis of a single, possibly flawed, implementation. The first colour televisions sucked, but colour television became ubiquitous.
My point is that the current LCD technology is flawed by design.
Of course the manufacturers have improved the respond time and viewing angles but black sucks big time (even with high end monitors).
Let me get this straight, I like working and gaming with a LCD. But the experience could be much more better. I put a(calibrated) Samsung LCD 275T and a Pioneer Plasma Kuro side to side and the difference was day and night.
Of course the manufacturers have improved the respond time and viewing angles but black sucks big time (even with high end monitors).
Let me get this straight, I like working and gaming with a LCD. But the experience could be much more better. I put a(calibrated) Samsung LCD 275T and a Pioneer Plasma Kuro side to side and the difference was day and night.
LED helps in backlight bleeding because there are many more LEDs that are controlled individually. When it doesn't need to be on, it turns off, so there is no backlight bleeding because there is no light.
MrGuvernment
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Apple already has led displays in their mac air.
Except that no monitors actually do that yet, only some expensive TVs and that still brings on another set of artifacts. The only solution to backlight problems is to move to a backlight free technology (SED, OLED).
There isn't much lcd led technology right now except for expensive TVs.
http://www.crutchfield.com/S-Q6nHhjhk7UO/App/Product/Item/Main.aspx?I=305LNT4681
LED SmartLighting enhances contrast and black level performance
Samsung's SmartLighting technology is a whole new approach to LCD screen illumination. On typical LCD TVs, the backlight illuminates the entire screen equally at all times, no matter what is happening in the video image. The LN-T4681F's LED array is divided into a grid of independently controllable sections, to accurately display both dark and bright areas of an image. By taking advantage of the brightness and speed of LEDs, Samsung achieves an incredible maximum contrast ratio of 500,000:1.
Definitely looking forward to OLED...
(Hopefully something bigger and cheaper than Sony's current 11" offering. Though if I were rich, I'd be willing to try three of them together in a multi-monitor set up...)
Certainly
http://www.behardware.com/articles/654-4/xl20-samsung-s-1rst-lcd-led.html
better than LCD monitors with standard CCFL backlights. Differences can attain up to 50% and more commonly 25% between two areas.
Yeah, that's what I thought would be more ubiquitous by now, and cheaper, too. Supposedly using an LED backlight was to be cheaper than a CCFL backlight. Was there something in production that happened along the way?
taylorwilsdon
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My Macbook Pro is LED backlit, as is the comparable Dell model.
It hasn't been a mainstream success in the desktop/office monitor market, but its trickling into high end TVs and small laptop screens.
It hasn't been a mainstream success in the desktop/office monitor market, but its trickling into high end TVs and small laptop screens.
See post #30
FALSE.
I've read this long ago.
You say:
"An LED grid eliminates this random ass defect".
Test says:
"The XL20s result is a bit disappointing at first. The gaps are moderate less than 8% form one corner to the other but not reduced to zero."
Look at this - a larger monitor with regular BL.
LED backlight guarantees wider color gamut, nothing more.
Actually we still need to place a good monitor between LED BL and our eyes.
According to Displaybank's analysis, the penetration rate of LED LCD TVs is predicted to start growing fast from 2010, topping 3.5% by 2010 and 7.5% by 2011, up from 0.1% in 2008
http://www.displaybank.com/eng/research/report.php?mode=show&id=508
[21CW]killerofall
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I don't see LED LCD monitors going very far as buy the time they start getting affordable OLED monitors will be right on their tail and will dominate as the image quality of OLED's are superb and response times are less than 0.1ms. You can buy an 11" OLED TV for $2500 from Sony right now (link). Just think that in 10-15 years you will be able to buy an affordable 24" OLED monitor that you can roll up line a poster board and take with you anywhere. (Flexible OLED screens have already been made but only in small sizes (2.5") and aren't ready for mass production. Video) No backlight FTW!
Do OLEDs have a durability problem?
http://en.wikipedia.org/wiki/Oled#Disadvantages
http://en.wikipedia.org/wiki/Oled#Disadvantages