LCD/Plasma/DLP @ 1080i? (1 Viewer)

[Camp]

Most, if not all, currently available LCD, DLP, & Plasma sets (that I've seen) only run up to 720p. I'd like native 1080i as well. When can we expect to see TVs using these technologies at 1080i?

Last I heard broadcasters were sketchy with plans for 720p.

 

[Bill Slack]

There's a JVC(?) DLP set that does 1080p, but I don't think it's quite released yet.

You won't see any fixed pixel displays that are interlaced.

 

[Camp]

You won't see any fixed pixel displays that are interlaced.

Doh! That makes sense. Didn't think about that.

So, is there a work-around for this? Will manufacturers have to make displays capable of 1080p (a difficult task as I understand it) or will the displays convert 720p to 1080i?

What's the point of a 720p display if no one broadcasts in 720p? I guess that's what I'm really asking.

 

[Bill Slack]

Oh. All the displays currently scale 720p->1080i. With a good internal or external scaler the results can look fantastic.

And the sets generally aren'y 720p anyway, buy fairly close. 1080p might may be preferabble, but like you said, it's difficult (and more importantly) really expensive to pull off.

Give it a few years and that's what the high-end stuff will be. For now, the best fixed pixel displays look quite good, though they all have problems with black level.

 

[EricHaas]

Bill is largely correct, but not completely. There is an exception. Plasma glass panels based upon ALIS (Alternate Lighting of Surfaces) technology display 1024 horizontal lines, interlaced. This is an exception to the rule that fixed pixel displays are never interlaced. The resolution of all ALIS panels is 1024x1024i. 1080i on these displays is not scaled at all, but it isn't quite displayed natively either. The display simply crops 28 pixel rows from the top and 28 from the bottom (probably barely noticeable to the naked eye). Examples of ALIS based panels are the Fujitsu 4242, a Hitachi based on the same glass, and a Sony model also based on the same glass (but different electronics).

Most people think the ALIS panels have poor PQ for SDTV and DVD sources. Their 1080i performance is of course very good, but perhaps not sufficiently superior to sets with 768p native resolution to justify either the higher price or the poorer PQ with lower resolution sources.

 

[Camp]

Thanks guys, good info.

I have a question about this statement:

1080i.

The display itself does the scaling? Is that correct? I thought this occured in the HD receiver?

 

[EricHaas]

It occurs either internally in the display, or in an external scaler which could be in a set top box. AV receivers do not have scalers. Receivers pass video signals; they do not process them.

 

[Camp]

I didn't mean an AV receiver. I was talking about the "set top box" as some of them (direcTV, Dish) are also called "receivers".

 

[Bill Slack]

Yes most (all, afaik...) HD receivers will scale between 720p/1080i. Most plasma sets list 1080i,720p and 480p as acceptable inputs though. That doesn't mean they necessary do a /good/ job scaling...

 

[EricHaas]

Ah, come to think of it I have heard of HD set top boxes referred to as "receivers."

All fixed pixel displays have onboard scalers or they would only display perfectly native sources without an external scaler. But the quality of internal scalers does vary greatly.

Among plasmas, most enthusiasts will tell you that the Fujitsus have the best internal scalers.

 

[Bill Slack]

Eric:
You seem to know a lot about Plasma displays!
I'm curious as to how interlacing works on a fixed pixel display (and why it's done...) Any links or info appreciated. Thanks.

 

[EricHaas]

Bill:
It has something to do with with electrode configurations. In a conventional display, a pair of electrodes is used to light each row of pixels. In an ALIS display, each pair of electrodes lights two rows of pixels, but each pair can only light one at a time. Hence, odd rows are lit every 60th of a second, and even the next 60th of a second. The idea behind ALIS is that there is a gap between each pair of electrodes and hence a gap between each row of pixels in a conventional display. The ALIS display supposedly closes this gap by having each electrode pair control TWO rows instead of one. This is why they have more horizontal pixel rows. Also, the interlacing that ALIS displays do is supposedly superior to conventional scan line CRT interlacing where each scan line is lit one at a time since ALIS displays light all odd then all even rows simulataneously. Sort of across between interlaced and progressive.
I can only find links from Fujistu, Hitachi, Sony, et al. so this information has the drawback of being written from a marketing perspective. Example:
http://www.fujitsugeneral.co.jp/engl...s4220/alis.htm
You might also check out the plasma FAQ over at AVS.

 

[Rob Tomlin]

There's a JVC(?) DLP set that does 1080p, but I don't think it's quite released yet.

Really? This is the first that I have heard about this. You do question whether it is actually JVC, which is highly unlikely. JVC is promoting their "D-ILA" LCOS technology as competition to DLP.

But, whether JVC is the company coming out with 1080p is not really the issue. Is any company really releasing such a product?

Any info or links you could provide would be appreciated!

 

[Gabriel_Lam]

Well, JVC does have a 1080p capable display, but it's on their enormously expensive DLA-QX1 flagship D-ILA projector.

2048x1536 native resolution
7000 ANSI lumens
1000:1 contrast
10 bit color processing
HD-SDI capable input available
It's also 187lbs without lens, and $225,000 (also without lens). It uses a 2000 watt Xenon arc lens, which gives it excellent color fidelity. It's also always a waiting list to get a QX1.
JVC DLA-QX1 Projector

 

[Bill Slack]

Oops!
I was thinking of the Toshiba set with JBC D-ILA LCOS chip in it. Sorry... but, I was on the right track.
I guess I need to hire a fact-checker.
Here's a current thread on it:
http://www.hometheaterforum.com/htfo...threadid=38082