Passive vs Active 3D glasses

[Got2LoveGadgets]

Is there much difference between passive and active 3D glasses? I for one would prefer passive glass for use in the home as using active glasses must increase the chance of problems if the two become un-synced? Does anyone have any experience with the two?

[RiseDarthVader]

I have seen IMAX 3D in passive and active and both work great. The only time that you will have issues is when the battery needs charging otherwise everything should by in sync and good to go.

[Afrobean]

They do shutter glasses sometimes in IMAX3D?

I've never had any experience with that. I'd think they'd all be circularly polarized. The handful of times I've seen 3D there, that's how it was done.

And yeah, I'd say that passive is better, but the current screen technology doesn't really support it. However, 240 Hz screens CAN display the 48 alternating frames per second required for stereoscopic 3D with shutter glasses at film's native 24 fps.

[RiseDarthVader]

They used to use shutter glasses AGES back at IMAX Sydney. They were like these huge massive goggle/helmet sort of things that had a strap to hold onto your whole head. And the glasses you looked through were probably 10cm height and width. So glad they have polarized 3D now and todays shutter glasses are as small as the Real-D glasses.

[ay221]

I found this at another website:

http://forums.nvidia.com/lofiversion...hp?t51103.html

....Passive polarized setup (i have it myself): Works by the principle two projectors showing each eye on a special screen (so called silverscreen). Exactly the same principle as an IMAX 3D-cinema.
Upsides: For viewing you only need polarized glasses like when viewing the IZ3D. If more than one want to watch, only a pair of those polarized glasses each are needed. Ghosting rejection (experienced) is superb! I've seen nothing get close to it. Even though by a measurement you might have a ghosting rejection about a factor 80-100 (don't recall exactly but Jahun have a thread at the mtbs3d with a lot of valuable points). The light output is great since you have one projector for each eye. Guaranteed flickerfree reproduction too.
Downsides with this setup: Only one and it's a big one. It's really expensive! You need two projectors, one silverscreen or a special backside projection screen if you have the space and two polarization filters for each projector. The price of a decent silverscreen is about three times as much as an ordinary projectorscreen.....



So I guess for those without a setup like this we have no choice but to use shutter glasses?

[JamesN]

Passive 3D glasses rely on polarized images, which are only possible with front-projection systems. Such setups typically require two separate projectors with polarizing lenses or a single projector that can alter polarization with each frame. They also require a special "silver" screen that retains the polarity of the projected images. Although possible to implement in home theater environments, they are nonetheless impractical for all but the most hardcore of 3D enthusiasts.

Active 3D glasses (typically referred to as "shutter-glasses") rely on alternating left/right images and synchronize to the refresh display of those images. When the left image is displayed, the glasses effectively "black out" the right lens, and when the right image is displayed they black out the left lens, thus ensuring that the right and left images are received by the appropriate eye. If a high enough refresh rate is achieved, the "blacking-out" of each eye is virtually imperceptible.

Unlike passive systems that rely on polarization, active 3D can be achieved on a variety of display technologies, both front projection and direct-view. Currently plasma and DLP technologies are more suited to 3D than LCD (which has issues because of slower refresh rates and pixel persistence).

When 3D Blu-ray becomes a reality, expect active shutter-glasses to be part of the deal.

[syncguy]

Originally Posted by RiseDarthVader

I have seen IMAX 3D in passive and active and both work great. The only time that you will have issues is when the battery needs charging otherwise everything should by in sync and good to go.

Good to hear that active shutter is as good as polarized systems. I have never used active shutter glasses. Just worried about the reliability and robustness of these electronic glasses. Would they be able to stand day-to-day (rough) usage.