Apple LED-backlit Laptops?

[Bregalad]

Just as a CRT display uses rows of red green and blue phosphor lines or dots, couldn't a display be made of rows of R G and B LEDs? The problem I see is that LEDs probably can't be made small enough for a computer display or if they can, it would cost too much to make displays with millions of individual "lights".

On the laptop side of things I have to wonder just how much of a power savings could be achieved with LED backlighting. It's currently impractical to light rooms with LEDs because fluourescent lighting is almost as efficient at converting power to light while costing far less and yielding a broader spectrum of light. Scaling down to LCD panel size doesn't alter the basic physics.

 

[ChrisA]

Yes, I forgot about those!

Oy, though! As long as it doesn't have that pulsating look to it... I know 60Hz is faster than the "frame rate" of the human eye, but something about those pulsating LEDs still grinds my gears.

-Clive

I've got an LED dive light that has one LED and runs at either 6 or 4 watts. There is zero flicker. I would imagine the flash rate is well over 1,000/sec

The best thing about LED is the range of adjustment. They could but a 6W LED in that would allow you to use the screen as a flood light but it could adjust down to near zero for watching movies in a dark room

 

[matticus008]

This is a good point. An example of this in everyday life comes from break lights in certain high end cars like range rover, bmw and mercedes benz. Another example comes from the lightbars and undercover lights used by some police agencies. Ironically, the two examples that i gave often tend to be paired together when on the road as well.

Actually, typical LED brake lights operate two different sets. The "bright" LEDs are illuminated when the brakes are applied; when the pedal is released, only the "dim" set remains active. Reflective and silver lenses disperse the light, but you can clearly see that the entire lamps are not illuminated when the brakes are inactive. That's not to say that the voltage regulation method isn't used at all, but it's substantially less common.

LED back lights allow the displays to be thinner.

Not particularly, for large displays as in notebook computers--you still need some method of spreading the light uniformly across the panel. It's unlikely that Apple would build its display housings any thinner even if this weren't the case, as they'd be risking a loss of rigidity. In cell phones, iPods, and the like, there can be some worthwhile space savings.

 

[Butthead]

On the laptop side of things I have to wonder just how much of a power savings could be achieved with LED backlighting. It's currently impractical to light rooms with LEDs because fluourescent lighting is almost as efficient at converting power to light while costing far less and yielding a broader spectrum of light. Scaling down to LCD panel size doesn't alter the basic physics.

Do not confuse high output room lighting requirements with lighting a screen. Put common inexpensive 4 tube, 32w energy efficient T8 flour light in the ceiling of a room, put in a few more fixtures like this, and notice how much light is needed to light an entire room. No big screen TV, plasma or LCD could output enough light to overcome the brightness of thousands of lumens output be a room lighting fixture.

FYI, a single 3watt LED (forget about 5watters, they're insane) can output upwards of 180lumens (current expensive higher efficienty samples @60lm/w) but they get extremely hot! Think how many LED's you'd need then to replace a single 32w T8 tube, which by design distrubutes the light it produces evenly over a broader area than a LED that has a lens. It's an apples and oranges comparison. Home/business lighting large areas has nothing to do with small areas like the screen of a computer. You need a cooling heat sink, if not cooled properly the life span is drastically reduced as well as an efficiency gains just out out the door, they become very inefficient when allowed to get too hot. The 100lm/w LED's that are available which would be comparable to the most efficient fluoro based backlights, are only that efficient in very small sizes that don't heat up nearly as much as a larger LED. you're talking 5mm or smaller sized LED's, then they don't consume large amounts of current, so they don't get too hot.

LED backlighting will become common place, once the cost is equal to or less than other current technology CCFL backlighting (which as you should know, is not exactly cheap when you need to replace one on a laptop), perhaps in a year, or it may take longer. Perhaps in several years (it's been promised now for 5+years) OLED or SED will be the Holy Grail, not requiring backlighting, and therefore allowing both energy savings as well as allowing for thinner screens

 

[MattInOz]

Why just laptops?
I mean why wouldn't apple switch all it's screens and buy in bulk and save.

If what we are talking about is screens for same brightness or better are using say half the power, then that power saving is in pure waste heat. That translates for a machine like the iMac to a faster processor either CPU or GPU in the same case. Or a smaller case.

 

[macEfan]

That would be cool. LED's have come a long way ( and hopefully have a long way to go!) I wonder how much power that would save.

It would save a lot, considering 60 full size christmas light LEDs use only around 4 watts of power. Additionally the LED displays will be more enviromentally friendly, with no mercury in them. LED's also don't burn out as far as I know, becuase they don't have filiments. The electric charge just "jumps" from one terminal to the other.


LED's have come a long way, thats for sure... I recently had the oportunity to see a LED prototype from the 70's. HP was the first company that tried to get them to be used mainstream. It was cool to see the little prototype model flashing various colors of light, all running from two double A batteries

 

[Aniej]

Hey butthead, ha I always wanted to have a good reason to post that on here thanks.

Regarding the samsung tv, can you point mr to or post a link for it because the press release relates to the small monitor you mentioned.

 

[ClimbingTheLog]

color is fine

the color is fine - some slide scanners switched to LED a few years back.

the fluorescent tubes they used previously would change color over time but not so the LED's.

obviously, color is critical (though it can be filtered and adjusted to fine-tune)

 

[popelife]

Sony's TX3 ultra-portable notebook has an LED-backlit 11" widescreen display.

The screen is pretty nice to look at, and it's probably only 4mm thick.

The TX3 never fails to get a "wow, what's that?!" from punters. Even me, and I'm not wowed easily.

 

[Zadillo]

Sony's TX3 ultra-portable notebook has an LED-backlit 11" widescreen display.

The screen is pretty nice to look at, and it's probably only 4mm thick.

The TX3 never fails to get a "wow, what's that?!" from punters. Even me, and I'm not wowed easily.

Yeah. I think that Sony also uses the same sort of LED backlighting on the high-end "premium" versions of their SZ series (which allows the screens to be thinner and brighter than the non-premium). If y ou have a SonyStyle store or another place that stocks Vaios, you can see this screen technology in a laptop like the Sony SZ370 (or again like the TX series).

 

[DMann]

Likely

Incorrect, there are single color white (which tend to be rather bluish, like that you might see in a flashlight), and other single color LED's on die. And there are RGB primary colors on a single die, LED's that can be very accurate with colors, more so than the CCFL backlights currently in LCD screens.. Go to Cree's, or Nichia's websites and read up on them.

However, I think this story is pure bogus speculation. While it is technologically possible, I'm not aware of pricing that would make this possible currently (I could be wrong about that, perhaps we are now at economy of scale just like with NAND memory starting to replace hard drives in iPods, and in a year or two, laptop drives).

I should point out that according to Sharp, in announcing larger sizes of bigscreen LCD TV's earlier this year (or was it last fall?) latest LCD tech was upping the ante as far a color reproduction, but LED backlighting can surpass accuracy of any other LCD tech. LED backlit LCD's have the widest current color gamut, as well as accuracy (other than old some very high-end CRT's). Tests have shown this to be true (I forget which PC centric site published a review). Do a search on NEC's early LED 21in monitor, and you'll find that review re: color accuracy.

http://club.cdfreaks.com/showthread.php?t=195959

What is interesting is that you can see a visible difference in colors being displayed in the demo picture at the link above, but without being there in person, you wouldn't be able to see that full color gamut via images posted on the internet .

Samsung's just announced/released 20in XL20 model, designed for professional uses, is naturally quite expensive at $2k list. But they have also announced (hasn't shipped yet, but is supposed to be available now) a 40in LED backlit LCD TV with estimated $3,000 price tag.

http://ledsmagazine.com/articles/news/3/11/6/1

http://www.macnn.com/articles/06/10/25/samsung.xl20.display/

http://www.samsung.com/PressCenter/PressRelease/PressRelease.asp?seq=20061104_0000298342
"Traditional LCD screens typically cover only 82 percent of the NTSC standard color gamut (CRT covers 76 percent), while the new XL20 utilizes a unique light emitting diode back light unit (LED BLU), increasing the color gamut up to 114 percent of the NTSC color gamut.

The LED BLU increases the ability to create significantly enhanced images producing a more natural range of color, and covering the full Adobe RGB natural color space / gamut."

Being the 1st of it's kind the 20in XL20, if engadget is correct on the spec's is a very disappointing brightness of 250nits. While Cree has newer, 70lm/w and 100lm/w very small size efficient LED's, they are leading edge tech, so even in quantity, I doubt you could get them at a low enough cost to produce a screen with 1,6knits; most dubious figure I see in the Digitimes 'rumor'.

http://www.engadget.com/2006/09/22/samsung-busts-out-the-720td-711nd-and-xl20-lcds-in-japan/

OLED (which does not require backlighting, given that technology) in theory would be capable of being more accurate, but last year's announcement by Samsung of a 40in prototype OLED TV, was producing something on the order of only 80% of the NTSC color gamut, IIRC. LED backlit LCD's in large screen TV's are more accurate.

Less accurate color reproduction, lower cost LED's that might be bright enough, could make it into a laptop screen (or desktop monitor, no reason not to have them there) this year, but probably not until later in the year, when prices come down, technology scales up on the latest gen of LED's to make it so.

Best thing about LED backlighting, besides greater color accuracy, wider color gamut, is evenness of illumination of the entire screen, one of the big flaws of current LCD screens used in laptops.

I could see that being true.

 

[iMeowbot]

Somehow I see this happening in the new iPod before it hits the laptops. Call me crazy...

This kind of backlighting is already used in the iPod line.

 

[Zadillo]

This kind of backlighting is already used in the iPod line.

I don't understand why people are talking about this like it isn't already available on the market. As mentioned above, you can walk into a store today and buy a Sony TX or Sony SZ feature LED backlighting.

 

[Digital Skunk]

It Better Matter

I hope that it matters. If putting LED screens on laptops improves battery life by leaps and bounds, or improves the brightness and quality of the screen exponentially; then I will be glad to see Apple embrace it. A lot of times there is some technology that everyone thinks is hot stuff, but after a few years it turns to crap and shows no substantial improvement (a.k.a. Zip drives)

PC makers embrace crap technology since they change their products every 2 or so months. Apple may take a lifetime to embrace something new sometimes, but at least they do their research and implement the new stuff the right way, they don't just throw it in the lineup.

If LED screen technology adds very little advantage over current LCD tech then Apple should forget about using it.

 

[Zadillo]

I hope that it matters. If putting LED screens on laptops improves battery life by leaps and bounds, or improves the brightness and quality of the screen exponentially; then I will be glad to see Apple embrace it. A lot of times there is some technology that everyone thinks is hot stuff, but after a few years it turns to crap and shows no substantial improvement (a.k.a. Zip drives)

PC makers embrace crap technology since they change their products every 2 or so months. Apple may take a lifetime to embrace something new sometimes, but at least they do their research and implement the new stuff the right way, they don't just throw it in the lineup.

If LED screen technology adds very little advantage over current LCD tech then Apple should forget about using it.

It does help both in screen quality (again, you can easily witness this today by looking at the screen of a Sony Vaio SZ370 or Sony TX series laptop) and to some degree in battery life (I've heard that the Sony Vaio SZ370 gets around half an hour to an hour of extra battery life than the non-premium Sony SZ330, although I am not clear on whether that's with both at highest brightness or something else). If the Sony displays are any indication, they are noticeably brighter, richer and smoother and more consistent than most other laptop displays I've seen.

 

[RichP]

I think digitimes just makes partially educated guesses with their macrumors.

We can all rather agree that we are due for some "next generation" laptops from apple this spring. Santa Rosa chipset with all the goodies it offers (Robson caching) will be out, and LED screens are a very real possibility, given the price is right. Realize with LED backlights, you are adding a repeating manufactured element whose quanity is dependent on screen area. As screen area increases, you add ALOT more LEDs. Hence that NEC screen cost a fortune.

 

[Counterfit]

Upon further review, it appears it is the display they are talking about. sorry. But, this does have a silver lining. Perhaps this rumor is really true and there is a basic move towards what I said, backlighting the keyboard with an LED, what is currently used for the keyboard illumination? Please don't tell me its an LED it will cap off my already cr*p of a day.

Since I haven't taken one apart, I can only speculate that it's an LED piped through some fiber optics (per Apple's advertising, they call it a Fiber Optic backlit keyboard, I just call it awesome )

 

[Stridder44]

So wait, while Im reading these new LED screens are better pretty much in every aspect, are they also brighter? Or at least as bright (as a current iMac display)?

 

[ltcol266845]

Why just laptops?

Maybe the truth is somewhere in between. It seems to me that LED back lighting technology is not quite ready for mainstream use in laptops yet, but it has already been used in larger, desktop formats. And there are already other rumors that Apple might be releasing new displays soon. Perhaps those new displays are to have the LCD back light.

KS

 

[Zadillo]

Maybe the truth is somewhere in between. It seems to me that LED back lighting technology is not quite ready for mainstream use in laptops yet, but it has already been used in larger, desktop formats. And there are already other rumors that Apple might be releasing new displays soon. Perhaps those new displays are to have the LCD back light.

KS

Sure it's ready for mainstream use in laptops. Again, they are used in Sony's high-end SZ laptops, and their TX laptops. Size definitely isn't the issue (the SZ and especially TX are some of the lightest laptops around, and also have some of the thinnest screens).

The only issue I would see would be the additional cost they seem to add right now, but like anything else, that will probably come down as more companies like Apple and HP adopt it (kind of like the old Active Matrix vs. Passive Matrix LCD issue).

-Zadillo

 

[shamino]

Remember, all of our newer Macs have a dimming LED (sleep light). Maybe it's just me, but I can see a pulsation effect on the sleep light if I move my eyes side to side really fast.

LED-based digital clocks also have a noticeable effect like this.

But the frequency used for the dimming doesn't have to be 60Hz. It can be anything - it's the duty cycle (the percent of time on vs. off) that determines the overall brightness.

If people complain about flicker in the first generation of LED-lit panels, I'm sure they'll design the next generation to use higher frequencies, just like they did with CRT refresh rates in the not-too-distant past.

 

[kainjow]

It only makes sense to use something like this. Plus with the additional use of flash memory, battery life will be awesome this year Great year to upgrade to the new MBPs

 

[avalys]

Also, consider that the fluorescent backlights tend to dim over time, which shouldn't be a problem with LEDs.

 

[backspinner]

LEDs do dim over time as well, but not as much as the other light sources

 

[shamino]

LEDs do dim over time as well, but not as much as the other light sources

It all depends on the LED, the amount of power you drive it with, and how long it's on.

I've got several PC keyboards where the "num lock" light is so dim it is barely visible in a lit room. The other lock lights (scroll-lock and caps-lock) are still plenty bright, because they're almost never lit.