The viewer of stereoscopic displays has to use eye glasses. The two views required for 3D vision are obtained either by placing both views into the area of the screen, a method called area division multiplex, or by presenting the views as a time sequential display, also called time division multiplex. In the first approach each view can only exhibit half the resolution of a 2D display. Contrary to that, in the second approach the full resolution of a one-view display is maintained, but the addressing of the time sequential display must work at twice the speed of a regular 2D display.
For area division the light of the two views is polarized differently in order to distinguish the views. In case of a linear polarization, two perpendicular polarizations, crossed polarizations, are used, while circular polarization works with the right-handed and left-handed versions. The eye glasses have lenses, each of which allows only one of the polarizations to pass. So the right eye perceives only the image with one type of polarization and the left eye only the image with the other type of polarization. The solutions with area division differ in the way they create the second polarization from a given first one.
The eye glasses for the time division approach can also operate without polarization as shutter glasses in an on–off mode. While the image for the right eye is displayed, the right eye lens is transparent and the left eye lens opaque, and vice versa ...