Back light LED lcd, anyone ??

[ead]

Ok I know the "some what old" NEC
2180WG-LED
Had a back light driven by LED
Is there other LCD's in the market with it ?
Any why don't more brands put LED into the back of LCD ? seem like a very nice tech that can give a good result, isn't ?

 

[Benny]

Samsung XL24 and XL30
ViewSonic VLED221wm
Acer AL1917L and AL2216WLsd

+ gamut, homogeneous
- gamut, expensive

 

[Nenu]

There are a few Philips HDTV sets using LEDs but I found the power consumption figures confusing.
ie the 42PFL5603D 42" set uses 70W, the 37PFL9732D 37" uses 208W and the 32PFL9603D 32" set uses 139W.
No doubt there is a significant difference between the 42" and the others but it would be good to know what that is.

 

[ead]

What are the pluses and minus of those screens ?

 

[Benny]

What are the pluses and minus of those screens ?

on the plus side:
the backlight can be more homogeneous.
the backlight can be dimmed better than a tube so you have more options for dynamic contrast. (a feature I and many others prefer to turn off)
If the screen is large enough (40''+) it's possible to have a locally dimming backlight giving higher in picture contrast. (within limitations)

on the plus and minus side:
they got more saturated color (larger gamut) but since only few programs display colors accordingly, you will have oversaturated colors in almost all applications.

on the minus:
LED is more expensive than CCFL

 

[ead]

ok
So how is the response time of them and input leg ?
how is the Samsung XL24 (the only one I know that is wide and 24")
And won't the photos and things look better on them? or the usually LCD today with IPS are better ?

 

[Benny]

ok
So how is the response time of them and input leg ?
how is the Samsung XL24 (the only one I know that is wide and 24")
And won't the photos and things look better on them? or the usually LCD today with IPS are better ?

haven't seen data on input-lag, but it's basically a 245T with led backlight so I wouldn't expect anything speedy.

PVA and IPS it's the usual thing that has been discussed on this forum frequently,
or in short, most won't consider a pva for color critical work.

The LED gamut will show the more saturated colors if the photos were shot with a camera supporting a wider gamut, if they use sRGB standard colors they will look more colorful but not natural.

I forgot to include the 20'' MVA predecessor of the samsung monitors, it has been tested @ behardware and the data can be found here, http://www.digitalversus.com/duels.php?ty=6&ma1=88&mo1=316&p1=3023&ma2=36&mo2=167&p2=1698&ph=12
it's extremely likely that the 24'' will lag more than the 20''.


and when thinking about a XL24 don't forget that you could easily get a 30'' ips including colorimeter for much less, or a LCD3090WQXI including one for the same price..

 

[Nenu]

This is what I have found so far

42PFL5603D
42"
LED Dimming backlight, 70W operation
4 x 1.3 HDMI
Contrast 30,000
5mS
Viewing angle 176 degrees
Not available yet and not a lot of info around.
70W

37PFL9732D
37"
LED backlight, Light sensor, subwoofers, good image processing, Firmware upgradable
memory cards + USB,
3 x 1.3 HDMI
HDCP compliant
Contrast 8,000 / 1200
Brightness 550 nits
3mS using a new measurement so take this with a pinch of salt.
176 viewing angle
24p
100Hz
14 bit processing (claim 4 trillion colours which is utter bollox) - this is internal processing, the LCD itself is not affected by this and will remain either 8bit or 10bit or whatever it is. The processing involves dithering, resizing and 100Hz interpolation etc...
208W.

32PFL9603D
32"
LED backlight, Subwoofers
3x1.3 + 1 HDMI
HDCP compliant
Contrast 55,000
Brightness 500
24p
4mS using a new measurement so take this with a pinch of salt
176 Viewing angle
17 bit processing (claim 2250 trillion colours which is also utter bollox) - this is internal processing, the LCD itself is not affected by this and will remain either 8bit or 10bit or whatever it is. The processing involves dithering, resizing etc...
139W

LED backlights "can" and usually do give a wider colour gamut and even with a normal LCD panel will give richer colours so it can be a good plus to use LEDs. Ideally the Monitor will limit the dynamic range and use extended colour ranges where appropriate for new higher bit colour sources.
They have a much larger dimming range so generally have larger dynamic contrast ratios.
LEDs should cost much less to run but we can only see the benefits of this in the 42" set.
Time will tell why as its very hard to get hold of any more info.

Be sure to get a HDCP compliant set if you want to continue watching new Blu ray movies or 1080 res HiDef TV/Satellite after 2012 or whenever the HDCP flag gets enabled.

 

[Sycraft]

I'd steer clear of LED screens for now just based on cost. They are too much money for what they do. For example: The LED NEC monitor is 21", 4:3 form factor. The MSRP is $3500. Their 30" 16:10 monitor, which has nearly as wide a gamut despite using CCFLs, is only $2200 MSRP.

So unless you have a specific use for that wider gamut, I don't see the money as being worth it, especially since you get a smaller monitor. In terms of uniformity if you go for the NECs it doesn't matter since you can use colourcomp, which makes the panel extremely uniform.

Until the prices get a little more sane, I don't think they are a good buy.

 

[kleox64]

I'd steer clear of LED screens for now just based on cost. They are too much money for what they do. For example: The LED NEC monitor is 21", 4:3 form factor. The MSRP is $3500. Their 30" 16:10 monitor, which has nearly as wide a gamut despite using CCFLs, is only $2200 MSRP.

So unless you have a specific use for that wider gamut, I don't see the money as being worth it, especially since you get a smaller monitor. In terms of uniformity if you go for the NECs it doesn't matter since you can use colourcomp, which makes the panel extremely uniform.

Until the prices get a little more sane, I don't think they are a good buy.

I agree, the other thing that has annoyed is my samsung has paired PVA with LED's.

 

[BludyRutz]

i think part of the cost with led's is their working lifetime included. i would assume an LED backlit screen would last... uh... as long as the internal power supply lasts? those led lights (both in the lcd and backlight) would last upwards of 50 years and more of full-time use. surely the caps on the circuitry inside is the weak link?

then again i dont know of that many ccfl lcd's that burn out either.... my dad's 5 year old lcd (one of the first years they were massed marketed) has the power supply inside it die. the screen worked one day then nothing. dead. the backlight was still working, although not as bright as it was when new...

 

[djlenoir]

Will LED backlighted displays suffer from backlight bleed in the same fashion as CCFL backlighted displays?

 

[Nenu]

Will LED backlighted displays suffer from backlight bleed in the same fashion as CCFL backlighted displays?

Light bleeding is down to the LCD panel design and its surround, not the backlight itself.
This assumes the same brightness level as clearly higher brightness will bleed more regardless of light type.

 

[Michael Daly]

This is what I have found so far

42PFL5603D
42"
LED Dimming backlight,
70W operation

37PFL9732D
37"
LED backlight, Light sensor, subwoofers, good image
208W.

32PFL9603D
32"
LED backlight, Subwoofers
139W

I'm guessing the wattage numbers include the subwoofer's draw at max. It wouldn't be unreasonable for them to spec about 140W (37") and 70W (32") subwoofers.

 

[Nenu]

I'm guessing the wattage numbers include the subwoofer's draw at max. It wouldn't be unreasonable for them to spec about 140W (37") and 70W (32") subwoofers.

Possibly but I imagine the 42" has a sub too I just havent found the info to confirm it yet.
I expect the subwoofers to be well below 30W though.
I'm currently running a 60W REL sub and it shakes the whole house!