You've already seen
Samsung's new LED-backlit LCDs for 2007, now check what cross-K-town rival LG.Philips has in store. Last week's ICDL 2007 had LG.Philips demonstrating their 47-, 26-, 15.4-, 12.1-, 8-, and 7-inch LED backlit LCD panels. The big daddy 47-inch panel appears to be the guts of
the LG HDTV we heard rumors about. And just like we heard, this panel brings a Full HD 1920 x 1080 resolution and a "Mega CS"
1,000,000:1 contrast ratio for truly black, black-levels obtained though a process of local dimming. It's listed with a 500cd/m2 brightness, 178-degree viewing angle, 8-ms response, and 1.07 billion colors covering 105% of the NTSC color gamut. No word on release so we'll have to cling to the original "as early as Q2" hearsay for now. Meanwhile, the 26-inch panel brings a 1366 x 728 pixel resolution, 540cd/m2 brightness, 18,000:1 contrast ratio, 178-degree viewing angle, and covers a hot 136% of the NTSC color gamut. The 15.4-inch and 12.1-inch LED-backlit LCDs are destined for laptops. The 15.4-inch panel matches the
equivalent LED-backlit Samsung panel spec-for-spec only it comes in a bit dimmer at 300cd/m2 vs. Sammy's 330cd/m2. The 12.1-inch panel measures just 3.15-mm thin yet packs a respectable 1280 x 800 resolution, 400:1 contrast, 250cd/m2 brightness, and 16-ms response. The 20-mm thick 7-inch panel and 16-mm thick 8-inch panel are destined for navigation devices offering both a wide temperature range of operation and high-brightness. Great, nice to see LG, now please get that 47-incher onto the shelves with your
120Hz TrueMotion technology mkay? Oh, and
less than $2k... pretty please, with sugar?
Read -- 47-inch
Read -- 26-inch
Read -- 15.4-inch
Read -- 12.1-inch
Read -- 8-inch
Read -- 7-inch
posted Feb 5th 2007 8:27AM
Sounds great... except... think about what happens when one of those backlighting LEDs burns out. All of the sudden, your 'local dimming' become permanent. Sounds far worse than a stuck pixel, and it is guaranteed to happen.
It's about as likely as your picture tube burning out, which is way more of a problem than a single pixel, and it's guaranteed to happen eventually.
Do you have any idea how long it takes for an LED to burn out???
you are aware taht LEDs has a life of like 100-150yrs before they even start to dim right?
I want a laser HDTV. They sound better.
Please do not look at the laser HDTV directly as they would burn your eyes out.
Frick, that picture looks incredible.
Mantari- Does sound great and with LEDs' life span at 100,000 hours I really don't see an issue of burn out?? Do some research, LEDs are the future.
1. It is reasonable to assume a 100,000 MTBF for an LED. That is 11 years of constant use.
2. But that's a _MEAN_ time between failure. Not a guarantee.
3. A 47" TV could easily have 100 LEDs.
4. You're betting that all LEDs will follow the mean. Guess how many are going to fit outside of one standard deviation? Two standard deviations?
5. If you've had enough LEDs, you'd know that some *will* fail prematurely. Ask people who have run a number of LED christmas lights for two seasons.
6. Another example: one of the Aqua Teen Hunger Force LED displays on eBay? Did you see the one where a bottom LED was burned out? It happens more often than you'd like.
7. LEDs put out less light as they become older
8. White LEDs fade even worse as they become older because they put out UV light which hits against a white phosphor coating. That coating luminesces less and less over time.
9. Other issues can impact LED lifespan, such as heat.
10. A failure of a single LED will be apparent and will create a dark spot in the image.
I like LEDs myself, but experience is a cruel teacher. An expectation of 100 years before they dim is outrageous. Go to PlanetChristmas and ask them about how their LED based Christmas lights seem less intense when it comes to a second season.
I want the 10 foot version that outputs only 100 watts.
I believed that LED have a lifespan of 50,000-100,000 hrs. So LED TV/Monitors are in for this year?
It's still a backlit display so it still doesn't have a real black, and their isn't a 1:1 ratio of pixels to backlights, so edge effects at light/dark edges are guaranteed. Also, if you've seen these things, you realize that the 1000000:1 ratio is achieved by painful blinding whites.
Mantari is right but it needs to be taken in account that the LEDs will be surely be feeded with some sort of multiplexing not DC wich will increase their life even more, in the other hand i don't think that they will be replaceable i can imagine thousands of them embedded in a polycarbonate sheet with the lenses shaped in the material to guarantee uniformity. I think that advantages are more than drawbacks Power consumption, Dissipated heat, price, contrast ratio, weight against life expectancy. Think what manufacturers cares about.
Summarizing the above entries, there are three concerns:
1- What if an LED burns out?
2- What if an LED "dims" over time?
3- It isn't true-black, because they pump up the brightness to get their "1,000,000:1 levels"
1 - If an LED burns out, you go to your warranty card, and you have them replace either your entire set, or the faulty LED. That's what warranties are for. That's the best that any TV manufacturer can do for you (LCD, Plasma, CRT, whatever).
2 - If an LED goes dim, then the set can presumably detect the variation in impedance, and pump more power to that LED. I am not just taking a guess here. This set (by LG) can individually dim and brighten the LEDs. It controls them with some kinda on board logic system which is very responsive.
3 - The 1,000,000:1 is not achieved solely by brightening the backlight. It is achieved in part by the ability to DIM the backlight LEDs. This way, areas where there is no light being shown (black parts of the screen) are dimmed from the rear, rather than relying on the LCD's "windowshade" technique of just trying to block out all light.
It is this windowshade technique which is the LCD's Achilles' heel. The fact that the projected light is always at the same intensity, and therefore to get black, you have to try hard to "cover it up". You end up with the black areas of your screen giving just "dark gray". But this technology allows areas which are entirely dark to be dimmed down to near total black. LG has fixed the problem that plagues LCD here.
But what about the areas of the screen where there is "some" light. (Imagine the moon on the left side of the screen, on a darkened sky). Those areas will be tricked by your own eye. You look near the moon, and its not completely dark... bummmer... but luckily your eyes compensate, because you're looking at the moon. Your pupil dilation decreases (in milliseconds).
When you look to other (black) areas, your pupils re-dilate, but now you are looking at areas where the LEDs themselves are progressivly dimmed (as they move away from the part with the moon). See?