Originally Posted by Ron Jones
No - shutter glasses need a polarizing element in order to work. What it means if you are using a screen with a zero (0) rating for retaining polarization is that the orientation of the polarizing element in the glasses makes no difference. Thus you could use universal glasses such as the Xpand X103 and have similar brightness as using the projectors manufacturer's own glasses even if the universal shutter glasses have a different orientation from the 3D projector. If you do use a screen that maintains a lot of the polarizaton from an LCoS projector, such as the JVCs, then you need to use glasses that have polarization that matches that of the projector and you will get an additional boost in brightness due to the polarization of the light coming off of the screen, but with the wrong orientation on the glasses you would get a significant reduction in brightness.
I don't think this is quite right or I apologise if I misunderstood. (Edit: or perhaps I am just supplementing what you were already trying to say)
All light is polarised however we often use the expression polarised to mean a light source where all light is polarised the same way (in a single plane). A typical light bulb produces light that is polarised randomly and we often use the misleading term unpolarised. If you wear a pair of horizontally polarised lenses infront of a normal light bulb, some light will pass through and some won't. Confusingly unpolarised light does NOT mean all light will go through a polarised lens.
If the projector is outputting only horizontally polarised light, and then the screen makes it chaotic/random as it reflects it back to the viewer, then only the light that is STILL polarised horizontally will pass through the glasses and the rest effectively is thrown away.
Therefore by having a screen material that preserves polarisation will actually mean with the JVC glasses you have MORE light than a screen that does not preserve polarisation at all. There is no such thing as light not having any polarisation...if you imagine light as particles then imagine each particle is oriented in some direction.
With a screen material not preserving polarisation, then the JVC and XpanD glasses will behave the same and both will throw away the light elements not matching their polarisation. Neither will provide the brightest possible image, but both will provide the same image brightness.
To obtain the brightest possible 3D image, you would choose a material that preserves polarisation and stick with the JVC glasses. Another perspective, and this is an over simplification, is to say a 1.4 gain screen with polarisation preservation will probably be as bright in 3D as a 2.8 gain screen that doesn't preserve polarisation.