3D technology is difficult to ignore, with most cinemas offering 3D films and the rise in popularity of home TV 3D monitors. 3D monitors make it possible for users to feel like they are part of the action as their viewing experience is made more realistic by the extra dimension. But one of the major drawbacks which this technology has presented is the inconvenient glasses which must be worn to experience 3D monitors. Auto-stereoscopic displays offer an advantage on previous technologies (such as that used in cinemas) in that spatial viewing becomes possible without the inconvenient need for red and green, polarized or shutter glasses.

Autostereoscopy is the title given to displaying 3D images (stereoscopic images) without the need for special headgear or glasses worn by the viewer. 3D monitors use an optical illusion to provide their effect. They ensure that each eye sees a slightly different perspective which the mind then uses to process into a single spatial image. There are a variety of techniques which can be employed to enable 3D monitors without the need for glasses. Some examples are parallax barriers, volumetric and lenticular lenses. One technique which 3D monitors use is wider viewing angles, which use eye-tracking (following the eye’s point of view), but 3D monitors that display an image for multiple viewers mean that the display does not need to sense where the viewers' eyes are located.

Autostereoscopic 3D displays were first produced by Reinhard Boerner at the Heinrich Hertz Institute in Berlin in 1985. Prototypes of single-viewer displays using eye-tracking systems were being produced as early as the 1990s, but these days technology is moving towards different techniques to allow for multiple viewers simultaneously.

Most flat-panel solutions use lenticular lenses, an arrangement of curved magnifying lenses so slightly different images are magnified from different angles; and parallax barriers, a device placed in front of an image source consisting of a layer of material with a series of precise slits, allowing each eye to view a different set of pixels. Parallax barriers mean that one group of pixels has its light directed to one eye, and the other group to the other eye. As eyes are positioned apart and see slightly different distances, this produces the 3D effect.

Nintendo have used autostereoscopy technology in their gaming system Nintendo 3DS and Fujifilm introduced a digital camera with a 3D display screen in 2009. The world’s first 3D monitor which doesn’t require glasses was launched this year at the 2011 International Broadcasting Convention (IBC) in Amsterdam. The ORCHID OR-70-3D 7-inch camera-top monitor was displayed for visitors at the convention, displaying its hybrid of parallax barrier and lenticular technology. It can be used as a camera viewfinder or portable 3D production display.

The race to produce multi-view 3D monitors is therefore well underway in the technology sector. Many hold the view that autostereoscopic displays can eventually be used as a form of advertising, a fun effect in night clubs or amusement parks, and for use in information sharing such as in schools, museums, conferences and tourism information centres.