Abstract: A holographic optical element comprising at least two sets of regions, the regions of each set being different from the regions of the other set(s) and being interleaved or overlapping with the regions of the other set(s) and being constructed such that light incident on each set of regions is directed to a respective one of a plurality of viewing zones. The holographic optical element is typically incorporated in a display device such as a stereoscopic display device.

Abstract: A display device includes an image bearing device for generating one or more viewable images, optical elements for generating one or more viewing zones for viewing the viewable images, and an optical element with positive optical power. The elements are arranged and constructed such that the optical element with positive optical power forms a real image of the or each viewing zone and a virtual image of the or each viewable image, whereby the or each virtual image is visible to a viewer only when a light ray can be traced from the viewer's eye through the real image of an associated viewing zone, the optical element and the viewable image. The display may be an autostereoscopic display.