Glasses are required for all versions of 3D cinema systems. There are several reasons for this, and except for a few unique circumstances, this will also apply to home theater for a long time. Most 3D glasses come from the equipment manufacturers, which are built to handle "one size fits all" abuse. In the past year there have been companies offering alternative glasses, personalized glasses, so to speak. But Polaroid's announcement yesterday gives the subject a new potential, in this case, for the polarized lens systems, RealD and MasterImage.