Originally Posted by Ron Jones
Also be aware that projectors that use polarization require the use of a special sliver screen for viewing 3D. Since such screens are not well suited for viewing normal 2D video, most people that will probably need to install two screens, ie., one for viewing 2D videos and a 2nd screen for viewing 3D video. So while polarized glasses are cheap as compared to shutter glasses, the cost and hassle of needing a 2nd projection screen is a significant factor that must be considered.
The digital cinemas I been to using RealD 3D (circular polarization) had a normal looking screen that looked perfectly all-right during the 2D trailers before the movie. Couldn't see any hotspotting or other artifacts either. In fact, the screen looked like a perfectly normal white screen even with the lights on. Maybe a newly developed technology to retain polarization without going to silver?
Then we also have the Dolby 3D system which is based on slightly shifted wavelengths for RGB for each eye and narrow-band filter glasses. The system is passive, looks very good and doesn't require a special screen.
I don't like the active systems I have seen so far (3D TVs). The left and right eye images leaks into each other, creating ghosting, and I got eye-fatigue almost immediately. I think it was caused by the flickering nature of the glasses.