I've seen Polarized HDTV demos at CES...but it requires a
specially built LCD with a polarity switching cell layered on
top of the LCD pixels. The LCD pixels alternatively display
L and R images with the polarizing layer switching between
Vertical and Horizontal polarization. Hence the overall
image alternates between L and R images and the glasses
attenuate (imperfectly) the opposite polarization image.
Cost must be rather high to build the polarized displays.
OTOH, cost is very reasonable to add a polarization layer
on top of a DLP chip....as used in Mitsubishi & Samsung
HDTVs and ("Fake") IMAX 3D theaters:http://www.crunchgear.com/2008/03/11...replaces-film/
A similar pixel overlay is apparently used in the various
demos I've seen at CES for the "Look Ma, No Glasses" 3D
flat panels...but since the very blurry images DON'T use
polarization, I'm guessing it might use some sort of
MOVABLE? diffraction grating like you see in greeting
cards, etc. where the image changes as you move your
head back and forth.....
"Word on the Street" is that this magical technology is
at least 3-5 years away.....but I don't think it will EVER
be good enough for home use....polarized eye contacts
for EVERYONE might be a better solution....
In active shutter technology, the cost increase is pushed
to the shutter glasses....which "should" come down in
cost whenever this monster goes into mass production,
but if you have a few friends over to watch a 3D "event"
you might want to pass the donation hat.....
I wonder if the active shutter glasses used in theaters
are compatible with any of the new "3D Ready" HDTVs...
Simply reusing theater issued glasses solves this problem.
And my old video card came with a set of active shutter
glasses for playing video games.....how hard is it to
"adapt" these....and other existing 3D glasses.....
About the only technical advantage I know of for active
shutter glasses is a much better ability to switch "OFF"
the image to the opposite eye. Both require running
the image refresh rate at half the "normal" rate, so
120 Hz LCDs would alternate L and R at 60 Hz rate.
FYI: You can't lie down and watch 3D on Samsung 3DTV
LCD but you can on Panasonic 3DTV Plasma:http://tvtechnology.com/article/97018