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Samsung demonstrates the difference local dimming LEDs make for improving LCD contrast -- Image courtesy AVING.net
Backlighting technique gives LCD screens contrast capabilities that rival high-end plasma TVs

Following  the introduction of its first LED-backlit LCD HDTV last fall, Samsung unofficially took the wraps off several new LED-lit panels this week. AVING.net captured numerous images of the new monitors on display at the 2007 International Conference and Exhibition on Display LEDs (ICDL) in Seoul.

The flagship model was a 40-inch LCD panel destined for the HDTV market. The screen boasts 500 cd/m2 of brightness, 180-degree viewing angle, and 1366 x 768 pixel (720p) HD resolution. The widescreen panel also claims to offer an impressive 100,000:1 contrast ratio, achieved  using local dimming LED backlighting.

Conventional LCD panels with cold cathode fluorescent lamp (CCFL) backlights tend  to have lower contrast because the light source is constant and subject to leakage, making it hard for LCD screens to display true blacks. Local dimming allows the backlight to be turned off in dark image areas, generating a blacker black.

Samsung also showed off a high resolution 30-inch LED-backlit  model aimed at the PC market. The 2560x1600 (WQXGA) resolution LCD features 16.7M colors, 300cd/m2 brightness, 6ms response, 180-degee viewing angle, 900:1 contrast ratio. Samsung also displayed a 15.4-inch, 1440x900 resolution LED-backlit LCD panel with portable potential. Its 5.8-mm thickness and low 3.1W power consumption are tailored for use in notebook PCs. The panel offers 330cd/m2 brightness, 262k colors and a covers 45% of NTSC color gamut.

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That is quite a jarring difference.
By vdig on 2/7/2007 9:42:51 AM , Rating: 2
For the longest time, I did not know why the contrast ratio mattered much at all. Sure, I knew the technicalities, but for a general user such as myself, I really did not understand what the end difference was. All I can say is that the image on the right, when compared to the other image to the left, could not look any clearer in demonstrating what a good contrast ratio does.

I really hope the technology comes out for a price the end user could afford, or hope to afford in the near future.




RE: That is quite a jarring difference.
By masher2 (blog) on 2/7/2007 10:19:41 AM , Rating: 2
> "All I can say is that the image on the right, when compared to the other image to the left, could not look any clearer in demonstrating what a good contrast ratio does."

One problem. You're viewing both those photos on your own monitor...which itself is limited to a contrast ratio far less than 100,000 to 1. That makes it rather hard to see the actual difference between them. The camera taking the photos is likewise contrast-limited as well.


By dagamer34 on 2/7/2007 1:14:41 PM , Rating: 3
That makes it even more of a difference. If you can visibly see the difference in a photo and on your monitor, imagine what it looks like in person!


RE: That is quite a jarring difference.
By deeznuts on 2/7/2007 1:33:09 PM , Rating: 2
How do you know what he's looking at the picture on? What is the contrast ratio of CRTs? That's what I'm using (it's work and I'm selfless, delaying my upgrade to dual 19" LCDs so others can get them first, I dont' care at work) and the difference is good.


By masher2 (blog) on 2/8/2007 8:41:30 AM , Rating: 2
> "How do you know what he's looking at the picture on?"

A lucky guess? My first clue was his pegging the image on the right as the new monitor, when I strongly suspect its actually the one on the left. The rightmost picture certainly has higher color saturation, but the leftmost displays much more image detail, particularly in the darker sections...which is what contrast ratio is all about.


By Brassbullet on 2/7/2007 4:27:39 PM , Rating: 2
http://video1.bit-tech.net/lotr.zip

This is a good video to demonstrate a variable LED LCD vs. a Cathode lit one (good contrast ratio vs bad). Keep in mind that the blooming is only an effect of the camcorder used and the human eye would not see it the same.


By jmunjr on 2/8/2007 2:51:45 AM , Rating: 2
I am not sure what you are looking at but that picture is small and the differences between the two images is not much - one looks brighter than th eother. Wow! I'm sold!


Nice...
By 457R4LDR34DKN07 on 2/7/2007 3:36:55 AM , Rating: 2
Seems like a nice compromise until OLED screens. how much will they cost?




RE: Nice...
By killerroach on 2/7/2007 3:54:44 AM , Rating: 2
I think with stuff like that the conventional wisdom is "if you have to ask how much it costs..."

But, in all honesty, these will be sold at a premium over normal LCD displays, but how much more I have no clue. At a $200-$500 premium it might be worth it to me (if I had that much to throw at a huge display like that), but until then I'll just look at the pretty screens.


RE: Nice...
By ChugokuOtaku on 2/7/2007 7:36:01 AM , Rating: 2
I would assume less, or atleast it won't take long for prices to drop to where they are now, or likely even lower, since LED backlighting should actually bring the cost down.


RE: Nice...
By Brassbullet on 2/7/2007 5:16:42 AM , Rating: 2
Isn't this the same thing as the BrightSide LCDs that came out a few years ago?

I believe the list price for those was $49,999.


RE: Nice...
By therealnickdanger on 2/7/2007 8:51:06 AM , Rating: 2
I'm guessing that their target with these will be a bit more mainstream...


RE: Nice...
By michal1980 on 2/7/2007 9:28:30 AM , Rating: 2
I see a perium price for these, but with competition from teir 2 and 3 lcd manufactures, these panels might end up costing the consumer the same price as todays panels.

the lcd market is getting very very competative.

Unlike 2 years ago, all the lower price brands are putting downward pressure on the big dogs i.e. sony,samsung,sharp,mitsu.

Already the gap is huge... these big guys can't create a bigger gap if they want to sell.

as for oled. dont hold your breath, kind of like sed. There just not happening right now.


1366x768
By psychobriggsy on 2/7/2007 10:13:41 AM , Rating: 2
So this is a display with a wonderful contrast ratio and technology ... but it doesn't even have a 1080p resolution? I wonder what would be more important though - the contrast ratio, or the resolution. Would you even notice the lower resolution at 10 foot? You'll notice the better image quality however. Argh.

However it is a good start to bringing this variable brightness LED backlighting to the mass market. Definitely worth waiting for, in my opinion. The next generation should be even better and cheaper. Hurrah for technology.




RE: 1366x768
By UNCjigga on 2/7/2007 10:49:56 AM , Rating: 2
For LCD? Here's your answer: contrast and color win hands down!!! Think about it--most LCD panels sold today are 50" or smaller. If you're sitting 6-8 feet away from your HDTV, you'll barely notice a difference between 720p and 1080p at that size. But the difference between a traditional LCD's contrast ratio and color gamut vs. a LED-backlit panel with dimming is night and day--you can see it in the demo photo!!


RE: 1366x768
By DrKlahn on 2/7/2007 10:54:37 AM , Rating: 2
With 20/20 vision at 8' you need around a 50-55" display to fully resolve 1920x1080. 720p on a 40" set is certainly adequate.


RE: 1366x768
By jmunjr on 2/8/2007 2:52:24 AM , Rating: 2
No you can't see it i the demo photo..


RE: 1366x768
By hellokeith on 2/7/2007 10:56:04 AM , Rating: 2
Agreed. All new TV's over 25" should have 720p, 1080i, and 1080p input with native 1080p output.

This would probably make a good bedroom TV hooked up to the HD cable or HD satellite, but not a main watcher, especially with BD or HD DVD.

That said, I'm very glad they are getting away from cathode backlighting.


High Contrast LCD
By wallijonn on 2/7/2007 10:47:17 AM , Rating: 2
I'll wait for SED and laser TV, thank you very much.




RE: High Contrast LCD
By michal1980 on 2/7/2007 11:16:50 AM , Rating: 2
you'll be waiting a long time.

SED is on track to get the Duke Nukem Award. Its always coming out next year.


RE: High Contrast LCD
By OddTSi on 2/7/2007 3:31:26 PM , Rating: 2
Don't hold your breath for laser tv.
http://www.digg.com/tech_news/Laser_TV_a_scam


By KristopherKubicki (blog) on 2/7/2007 3:58:45 PM , Rating: 2
Samsung has a competing laser technology. We'll have more in the next couple days.


45% of NTSC color gamut?
By fanbanlo on 2/7/2007 12:12:19 PM , Rating: 2
45%? then what is the % of the tube tv?




RE: 45% of NTSC color gamut?
By johnnyMon on 2/7/2007 12:39:20 PM , Rating: 2
Maybe it's supposed to be 145%?


By psychobriggsy on 2/7/2007 1:03:38 PM , Rating: 2
35% - 45% NTSC gamut is fairly typical (as in: in the ballpark) for a 6-bit TN laptop LCD screen. You lose out on the brightest colours because of the laptop aspect, can't burn that much power in the backlight as (a) mobile device / battery life (b) closed laptop lid / heat.

I'd hazard a guess that a good NTSC CRT TV would get close to 100% NTSC gamut. Of course NTSC ain't that great a benchmark, but it is known.

Modern high-end LCDs and Plasmas are far better - 75% for mid-range and often over 100% at the top end.

Note that these figures are quite vague in my head from looking through specifications a month or two ago...


lcd tv vs lcd computer monitors
By atticu5 on 2/7/2007 7:18:10 PM , Rating: 2
just as a question, what is the difference between an lcd tv and an lcd comp monitor? why can't i buy a computer monitor and use it as a tv? does it not display television as well as an lcd tv? because i'd rather buy a high quality monitor with a high resolution so i can use it as a monitor and television, and if it can display a 1920x1080 resolution, isn't that the same as the 1080i/p settings used for hdtv?




RE: lcd tv vs lcd computer monitors
By Shining Arcanine on 2/7/2007 8:22:47 PM , Rating: 2
A LCD TV has a tuner, software and circuitry designed for viewing TV content while an LCD monitor has jacks, software and circuitry, designed for viewing PC content. With a media center PC, you could use a LCD monitor as a LCD TV.

It would be fairly expensive to create a dual-use LCD screen, given that LCD screens are specialized for either of the two aforementioned tasks, most likely to save costs.


By lumbergeek on 2/8/2007 2:25:20 PM , Rating: 2
re: "It would be fairly expensive to create a dual-use LCD screen, given that LCD screens are specialized for either of the two aforementioned tasks, most likely to save costs."

I have one - Samsung205BW - 20" Dual-input Widescreen 1680x1050 LCD. My HD Sat Reveiver is plugged into it via DVI-D and my PC via DSub15. It's my office TV. You can get a 22" one too. I'm sure it will get bigger. Only complaint is that it could be full-HD 1920x1080. I imagine one will be around soon enough and the kids will get this one.


By EastCoast on 2/8/2007 2:17:50 PM , Rating: 2
I won't touch it until they increase the resolution to accommodate the size of the monitor/TV. What kind of marketing crap have they thought of now? It's a waste of time to invest in something this backwards in my book. What they want to sell to you is a bright, high contrast, stretched (40" in this example) screen at 1366 x 768. My 19" monitor does 1280x1024, do you see the difference now?

Folks, don't believe the marketing hype. What makes a good picture starts first with the resolution, not the contrast ratio or brightness of it. To me ignoring the need to accommodate the resolution to the size of the TV/monitor to increase contrast ratio and brightness levels is putting the carriage before the horse (have the horse face the carriage) and instruct him to gallop. Don't waste your time with this, it's all marketing.




By EastCoast on 2/8/2007 2:26:55 PM , Rating: 2
What you end of having is a bright, high contrast picture that looks no different then a cheap monitor at the same resolution. Where is the crisp, sharp picture? Where is the detail? Oh, you won't get that with the current resolution will you? Tell you what take the movie Kingdom of Heaven and freeze the portion where is shows a wide angle of the massive army. With this current setup you will get a nice blurry contrast to the farthest side of the army/calvary at that resolution (1/3 to 1/2 mile away).

Now take that same clip and put it on a higher resolution without the high contrast. Using a 40" TV/monitor at 4096x2160 you will be able to see the eye balls (in detail) looking at the farthest side of the army/calvary (which can be 1/3 to 1/2 mile away).

Clear, crisp, sharp and detail picture is what the most consumers want. Not a whole lot of contrast!!!!
MEH!!!!!!!!!!!!!!!!!!!!!!!!!!!!


By masher2 (blog) on 2/8/2007 6:29:46 PM , Rating: 2
> "Clear, crisp, sharp and detail picture is what the most consumers want. Not a whole lot of contrast!!!!"

I'm sorry, this just isn't true at all. On the salesroom floor, consumers rate color saturation highest, followed by contrast. As for 1080p vs 720p, most can't tell a difference unless pointed out to them by a salesman.


Not 1080p
By electriple9 on 2/7/2007 3:09:35 PM , Rating: 2
I wont be buying this since isnt true hd, 1080p. I taught 1366 x 768 pixel was 1080i not 720p.
Thanks




RE: Not 1080p
By meson2000 on 2/7/2007 4:43:44 PM , Rating: 2
Actually, all digital flat panels like Plasma and LCD TV's can only display a progressive signal. 1080i singles are converted by the TV's internal scaler into 720p or 1080p depending on the TV. In this case, since the LCD only has 768 vertical pixels, it can only display 720p.

However, like some of the people noted above, at 8-10 feet away, its very difficult for your eye to tell the difference between 720p and 1080p.


By chinna on 2/7/2007 2:00:12 PM , Rating: 2
This trick has been known for years and no one has implemented until now. Technology was demonstrated by a company called BrightSpot couple of years ago( AnandTech article).

It is well known there will be light leakage( though it may vary by panel) this is best technique to attain best constrast as well as good black levels to LCD. Another benefits of using LEDs are better colors, longlife and less power consumption compared to CCFLs.

Hats of to Samsung for finally bringing it. I hope we will see many 40+ inch 1080P panel soon.




Some nerve
By FXi on 2/8/2007 12:59:39 AM , Rating: 2
Anyone else notice that the notebook screen is brighter than the 30" model? 300 cd/m2 is just not really all that bright. The notebook model at 330 is just hilarious. Good screens are 400-450. I guess Samsung isn't really at the top of the game anymore.

Too bad, since I was thinking about a 30" led backlit model...




Rip-off
By scrapsma54 on 2/8/2007 5:08:17 PM , Rating: 2
this is almost a rip off of Briteside techs Hdr display. Either way, what will the monitor do in Hdr games? I don't think a dimming leds will fix anything if Hdr requires both bright and dark. A swing and a miss.




Wonderful product!
By SprintSlash on 2/9/2007 6:15:28 PM , Rating: 2
If I read this correctly, I think this will be wonderful! We won't have to worry about light leakage in LCDs... Black will look the same as if monitor wasn't on!

Now.. does this mean.. average linux user would save more power than average Windows user... and average Windows user will save more power than average Mac user?

Save power by using gray instead of white, save more power by using black backgrounds (desktop, web site, applications, ...)?




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