Optical: systems and elements – Stereoscopic
Patent
1998-02-23
2000-06-20
Henry, Jon
Optical: systems and elements
Stereoscopic
359466, 359475, 359 15, G02B 2722, G02B 532
Patent
active
060784237
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a stereoscopic display device.
Many stereoscopic displays are known, there is a growing class of displays which provide for the viewing of stereoscopic images without the use of special viewing aids, these are known as autostereoscopic displays. They are all characterised by the use of some view determining means whereby each of the viewer's two eyes see a different image on a screen.
In a stereoscopic image two 2D images are used (we will call them half images) taken together they are known as a stereo pair. The stereoscopic effect is produced by the difference in perspective of the two half images. Each half image is formed at a certain distance from the viewer and the viewer's eyes will focus on the image. The eye's accommodation is one of the many visual cues interpreted by the brain to give depth information. As the eyes focus on the 2D half image any difference in depth sensation provided by the stereoscopic effect will contradict the depth information provided by accommodation. In practice it is necessary to restrict this conflict, otherwise viewer discomfort and eyestrain will occur. Autostereoscopic displays generally form their half pictures on the plane of a viewing screen. The size of the screen is usually severely limited by a number of factors and to minimise the conflict between accommodation and stereoscopy the 3D image needs to be formed close to the display screen.
It is an obvious characteristic of any three dimensional imaging system that images appear at a definite distance from the viewer.
A consequence of this is that the size of the 3D image is also determinable and clearly observable. (This may be contrasted with a 2D picture where no depth information is present so a large object will appear to be a large object even if the size of the image is small.)
As a consequence of the above existing autostereoscopic displays are incapable of displaying fullsize images of anything larger than the display screen itself; any larger objects must be displayed at a small scale and (unlike 2D images) will appear to be objectively small.
This fact limits the useability of existing autostereoscopic displays as the increased naturalism of the 3D image is compromised by the unrealistic representation of scale.
In accordance with the present invention there is provided a stereoscopic display device comprising: image comprising a different perspective view of a common scene; viewable image(s), the viewing zones being so arranged such that in use each of a viewer's eyes sees different viewable images thereby enabling the viewer to enjoy a stereoscopic 3D image of the common scene; and
wherein elements (a)-(c) are arranged and constructed such that the optical element forms a real image of the viewing zones and a virtual image of the viewable images whereby the or each virtual image is visible to a viewer only where 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, and wherein the means for generating a plurality of viewable images comprises image bearing means which lies between the optical element and the back focal point of the optical element.
The present invention allows the formation of the viewable image(s) at an arbitrary distance from the viewer and of an arbitrary size which is not limited by the size of the display itself.
A convenient analogy is a window: a very large scene can be seen through a small window. In the present invention, a large scene may be seen as if though the display window.
This invention provides a means whereby three dimensional images may be seen without the use of glasses, head mounted displays or similar inconvenient viewing aids, it also provides for the viewing of images which may be substantially larger than the display itself.
The image bearing means may be an--LCD, or a screen (which may be a holographic optical element) onto which the viewable image is projected.
A number of embodiments of the present invention will now be described wit
REFERENCES:
patent: 3447854 (1969-06-01), Minter
patent: 3802769 (1974-04-01), Rotz et al.
patent: 4535354 (1985-08-01), Rickert
patent: 4799739 (1989-01-01), Newswanger
patent: 5379133 (1995-01-01), Kirk
patent: 5418584 (1995-05-01), Larson
patent: 5703717 (1997-12-01), Ezra et al.
Orr Edwina Margaret
Trayner David John
Henry Jon
Richmond Holographic Research & Development Limited
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