Autostereoscopic displays do not require special glasses for viewing the two images needed for 3D perception and allow the viewer to freely rotate the head and even move around, but with limitations on the latter. This implementation will turn out to be more costly. In the simplest version of an autostereoscopic display the viewer can only perceive an undisturbed 3D image at some specific locations referred to as single view or multiview zones. This fortunately can be expanded to larger areas again, of course, at additional cost.
A further attractive feature of autostereoscopic displays is their capability to offer different 3D images depending on the viewing direction. This is a first step toward true 3D perception. Contrary to this, stereoscopic displays offer for each viewing direction always only the same 3D image.
Spatial and temporal multiplexing here are also the two basic approaches. The special components which avoid the need for viewing glasses are arrays of lenticular lenses or of parallax barriers, or various forms of light guides such as mirrors or directional backlights. They will be treated in different sections, while for each approach the multiview aspect, the use of projectors, and the switching between 2D and 3D, an essential sales feature for TV displays, will be included.
3.1 Spatially Multiplexed Multiview Autostereoscopic Displays with Lenticular Lenses
Figure 3.1  depicts the basic structure of lenticular lenses. In ...