Autostereoscopic display having a high resolution 2D mode

DETAILED DESCRIPTION It is thus possible to provide an autostereoscopic display having enhanced resolution in a 2D mode.
Advantageously the display may simultaneously display a 3D image and a 2D image.
This may be of great benefit when a display is used as an output device of a computer.
Preferably the display comprises at least two spatial light modulators arranged such that, in a two dimensional mode of operation of the display, picture regions of the image produced by a first spatial light modulator are interspersed with picture regions of the image produced by the or each other spatial light modulator thereby giving enhanced resolution in the two dimensional mode compared to the resolution in the autostereoscopic mode.
Preferably the display further comprises at least one beam combiner for combining the images produced by the first and second spatial light modulators.
Preferably the display produces a display output comprising a plurality of "windows", the windows being substantially contiguous at a nominal viewing position when in the autostereoscopic mode and being overlapping when in the two dimensional mode.
Preferably the spatial extent of the illumination source for each spatial light modulator is controllable, such that the illumination source has a first spatial extent when the display is operated in the autostereoscopic mode and a second spatial extent greater than the first spatial extent when in the two dimensional mode.
An autostereoscopic display operates by presenting different views to each eye of an observer.
EP-A-0 602 934 discloses, amongst other things, a beam combiner type display.
In a basic form, the display comprises a plurality of spatial light modulators each illuminated by a respective light source (which may comprise a plurality of light emitting elements).
An imaging system is included such that images of the light sources modulated by the respective spatial light modulators are directed along predetermined directions and, more specifically, are formed at "windows" at a nominal viewing position