AVS Forum banner
Status
Not open for further replies.
1 - 20 of 37 Posts

·
Registered
Joined
·
187 Posts
Discussion Starter · #1 ·
Some people look at the LCOS Sets and think right now LCOS is better than DLP. This is wrong. Those LCOS sets have 3-Chips, while a DLP set only have 1. A 3-Chip DLP projectors blows any LCOS projector away in PQ. The problem now and according to TI is that it will be many years before a 3-Chip DLP will be cheap enough for consumers, dont expect a 3-Chip to be under $10,000 by 2005 or even 2006, while by then 3-Chip LCOS will probably be under $4000. There is a reason Cinimas use a 3-Chip DLP and not a 3-Chip LCOS because the 3-CHIP DLP is BETTER.


So people who think LCOS technology is a better PQ wise are wrong.
 

·
Registered
Joined
·
32,172 Posts
Actually, cinema-sized LCOS projectors are in development.


Also, TI simply hasn't wanted to produce an inexpensive 3-chip solution. There loss. The market will start running fast from their technology if Sony can deliver the goods with LCOS (aka Sony's SXRD) and Toshiba continues to push the technology and Philips does too.


So when 2006 comes around and the 3-chip LCOS is $4000 and the 60" plasma is $4000 and the 3-chip DLP is still $10000, do you think there will even be a market for DLP? I sure don't. They'd better be a lot more aggressive than that.
 

·
Registered
Joined
·
278 Posts
It doesn't matter how superior a technology is if virtually no one can afford it.
 

·
Registered
Joined
·
807 Posts
Besides, from what I've read LCoS has the potential of equal or better contrast ratios and fill rates compared to DLP. Even if LCoS is not quite there yet, if it lives up to its potential its future is bright. Not to mention that it's produced on regular silicon using regular silicon technology (read: much cheaper to produce in large quantities than DLP)...


-Rob-
 

·
Registered
Joined
·
3,372 Posts
Pardon my ignorance here, but why would I want a 3-chip solution? Doesn't that just bring back alignment and conversion issues? One of the great things about my DLP is its one-chipness. So what am I missing?
 

·
Registered
Joined
·
963 Posts
Quote:
Originally posted by Salmoneous
Pardon my ignorance here, but why would I want a 3-chip solution? Doesn't that just bring back alignment and conversion issues? One of the great things about my DLP is its one-chipness. So what am I missing?
I agree 100%! My old LCD projection set (also a Samsung) used a single panel design, and I would never go with a three panel solution (such as the GWI and GWII) unless I could be guaranteed to never have a convergence issue.
 

·
Registered
Joined
·
93 Posts
>>why would I want a 3-chip solution?


One chip systems are inherently inferior since they can only display one color (R, G or B) at a time. If you hold your eyes perfectly still persistence of vision will trick you into seeing a color image. On the other hand if you move your eyes at all you'll see wonderful "rainbows" since each R, G and B pass will focus on a different part of your retina. Personally I'm astounded that not everyone sees rainbows on DLP sets. Guess I'm just lucky. :(


A three chip system displays all colors at the same time so you actually see a "real" color image.
 

·
Registered
Joined
·
807 Posts
>>why would I want a 3-chip solution?


In addition to the above: We're not talking about the convergence problems associated with tube-based RPTVs. Three chip LCoS/DLP/LCD etc. have the three chips and associated optics bolted to a very compact frame. They're aligned at the factory and never touched again. Alignment/convergence is not adjustable (not even by a technician as far as I know, you'd have to swap the optical engine). Convergence does not change over the life of the TV.


If there's a convergence error on my GWII I sure can't see it. Looks perfectly converged to me (and yes, I have looked at it with the AVIA test patterns).


-Rob-
 

·
Registered
Joined
·
187 Posts
Discussion Starter · #11 ·
A 3-chip has these advanteges.


1. More lumens and according to TI these are all GOOD lumens unlike the 1-chip design. A 3-Chip would have atleast 6000 lumens.


2. NO RAINBOWS


3. More Colors 16.7 Million Vs 35 Trillion.


Convergence is not that big of a problem like some people think it is.


Now one thing that is odd a 3 Chip LCOS only can do 16.7 Million Colors like a 1-Chip DLP. It can't do trillions of colors like a 3-Chip DLP I wonder why.
 

·
Registered
Joined
·
207 Posts
I don't agree with the original statement. LCoS has two distinct advantages so far - fill factor and black levels. However, I imagine over time the differences in these two technologies will be so small as to only effect the purest of videophiles.


irfoton
 

·
Registered
Joined
·
187 Posts
Discussion Starter · #13 ·
LCOS might have an advanteg in fill factor, but DLP has many times more colors, and it has a much greater lumens.
 

·
Registered
Joined
·
121 Posts
How far away are we from seeing a 1920x1080 DLP chip?
 

·
Registered
Joined
·
578 Posts
Let me add if you have a bad pixel on a single chip DLP you have a VERY noticiable black or white dot on your screen.


W/ a three chip design a bad pixel will be much less noticable and annoying.


I see rainbows w/ single chip DLP's even at the fastest color wheels too.


Plus LCoS doesn't have moving parts like the DMD w/ tiny little mirrors on tiny little hinges that I've seen get 'stuck' on about half of the DLP based front and rear systems I've seen -which is about a couple dozen.
 

·
Registered
Joined
·
207 Posts
lumens isn't the same as PQ. CRTs don't have great lumen output but most will tell you that a 9" CRT based FP or RP is the best PQ you can get.
 

·
Registered
Joined
·
32,172 Posts
DLP does not have more colors than LCOS.


Currently, DLP does offer much better contrast ratios than LCOS. That's a fact, but if Sony delivers what it claims with SXRD, it will be an historical fact, only.
 

·
Registered
Joined
·
187 Posts
Discussion Starter · #18 ·
Actually DLP does have more colors than LCOS. DLP has over 35 Trillion colors. LCOS still only has 16.7 Million colors. A 3-chip DLP while VERY VERY VERY expensive can produce the most number of colors, and the lowest lumens on a 3-chip is 6000 lumens, there are even some around 15,000 lumens.


Note I am talking about 3-chip DLPs.
 

·
Registered
Joined
·
252 Posts
If you are feeding your system DVD or HDTV source, more colors is meaningless.


The MPEG2 compressed data doesn't have 35 Trillion colors available.

It has about 16 million possible colors, because 8 bits were originally used to encode R, G, and B (8 bits each), less a few codes "reserved" for blacker-than-black.


And the human eye cannot distinguish 35 Trillion colors... So that number is pointless anyway.


There is no inherent reason you couldn't build a one-chip LCOS (but why?)

Three chips will always have some advantages:

no rainbows

brighter, by more than 2x, for the same light source


and some disadvantages:

higher cost due to 3 chips

higher cost due to the need to split the color paths, and reconverge them

possible convergence issues.


Overall, three chips systems look better.


Oh, and LCDs (which are always 3 "chip"/"panel") can be converged, both manually (by moving the panels) and sometimes by software controlled methods. It's just that in any 3 chip design, the factory convergence is close to perfect, and normally never goes out of convergence (unless you drop the projector, or need to replace a chip).
 

·
Registered
Joined
·
187 Posts
Discussion Starter · #20 ·
But we could encode movies like the do in the theatres with DLP. They encode the video so each color is many times more than 8 bits. Though thats probably why a movie like Starwars was Hundreds and Hundreds of Gigabytes.
 
1 - 20 of 37 Posts
Status
Not open for further replies.
Top