[Stuart Wright]

Ever wondered what a locally-dimmed LED LCD TV looks like underneath the picture? Toshiba explain the technology to us.

We hope you enjoy this production from the AVForums team. Please reply with your comments.
Options to view:

• Click the image below to begin playing now (requires Flash player installed on your computer)
• Via our TV productions home page at Home Consumer Electronics Videos from AVForums.tv
• Via our YouTube home (In HD for this video)
• Via our iTunes home

Also you may subscribe to the MP4 (for your video iPod etc.) by clicking this button:

[Buckster]

thanks Stuart - looks good these reports and interviews are superb - although I wish they'd stop calling them LED TVs when they are not

if they want to shorten LCD LED backlit TV then just call it a LCD TV

[lord-dudester]

very interesting that one, local dimming, something i'd never really considered

[Kalos Geros]

Everyone uses local dimming, it's not a Toshiba exclusive, though they sound like it is

[Pejxa]

Originally Posted by Kalos Geros

Everyone uses local dimming, it's not a Toshiba exclusive, though they sound like it is

yeah but not with 512 zones!

[Kalos Geros]

Yeah...at one point they will surely reach the 2-million zone local dimming backlight? I say bring it on :D though, by then probably OLED will become the predominant technology

[wess74]

I think Toshiba have stolen the march on their rivals with regard to 512 dimming zones. I'm guessing that the everyone else is using is about half (256 zones).
It will be very interesting to compare them when the reviews starting hitting in a few months time.

[Phil Hinton]

Originally Posted by Kalos Geros

Everyone uses local dimming, it's not a Toshiba exclusive, though they sound like it is

No they don't. Edge LED lighting in almost all cases (except Sony's new LX) use global dimming which lowers the luminance of the entire backlight in one zone; think Samsung. Local dimming on LED sets with backlights behind the screen as seen here, works by using zones of clustered LEDs which can switch independant of other zones and create a more accurate image. It's almost doing what a Plasma screen does already by having per pixel control over luminance, but in zones. Obviously if plasma does that already doesn't that give you an idea of why LED LCDs have some way to go yet?

[Buckster]

can the LEDs actually be reduced in output, or only off and on

just wondered how these sets fair with content that is just above black

ie does the grayscale get to a certain point, then take a vertical down to completely black ?

[200p]

Originally Posted by Phil Hinton

No they don't. Edge LED lighting in almost all cases (except Sony's new LX) use global dimming which lowers the luminance of the entire backlight in one zone; think Samsung.

Samsung's LE40A786 TVs use local dimming

[Phil Hinton]

Originally Posted by 200p

Samsung's LE40A786 TVs use local dimming

My post was more a quick 101 on the different uses, but thanks.