A DISPLAY SYSTEM

Abstract: A 3D information image display system (1) comprising a first order reflective surface (9) arranged substantially perpendicular to and between a pair of stereo images (8a, 8b, one 8b) of which is reversed left to right, wherein a viewer (21, 23), directing his line of sight towards the stereo image (8a) behind the reflective surface (9) and positioned such that one eye (21) views the stereo image (8a) behind the reflective surface (9) directly and the other eye (23) views the other stereo image (8b) reflected by the reflective surface (9), can readily appreciate the 3D information provided by the stereo images (8a, 8b).

Description: A DISPLAY SYSTEM This invention relates to display systems, and in particular to a system for displaying three dimensional information in a surprisingly simple and efficient manner. Printed publications, computer screens, televisions, liquid crystal displays (LCD) and other visual information media usually present images in two dimensions. Such images can give a degree of three dimensional "feel" to a picture, but a truly three dimensional (3D) image is impossible to produce on a two dimensional surface without the use of additional equipment or complicated (and expensive) manufacturing techniques or eye acrobatics. Known prior art attempts at producing visual images in three dimensions include the use of special spectacles to be worn by a viewer. However, the simple red/green lenses of the spectacles produce a three dimensional image in monochrome and the image tends to be poor if the spectacles are not properly positioned on the user or do not contain high quality filters. When polarised spectacles are used to create a 3D image, even if the polarising filters are of high quality and are precisely rotated with respect to the plane of polarisation, a risk still exists that the resulting effect will produce a ghost image. Lenticular cards are also known which incorporate a plurality of layered images which individually become visible as the card is tilted. Although in theory a large number of images could be incorporated in a single card, the cost of this would be prohibitively expensive and would still not produce a truly 3D image. "MAGIC EYE" (Trade Mark) pictures and stereoscopic pairs are known, but these require a viewer to control his/her eyes in a particular fashion, often resulting in the viewer going cross-eyed or wall-eyed and feeling uncomfortable. Three-dimensional holograms are also known, but these are once again very expensive to produce and do not lend themselves to the production of accurate colours in the image. In the light of the foregoing, books containing truly three dimensional images are very rare, partly due to the fact that it is uneconomical to produce such a book using known techniques. The present invention, however, overcomes this drawback and enables excellent quality three dimensional images to be viewed without the need for complicated equipment and without the viewer having to control his/her eyes in an unnatural way. The invention can, however, also be applied to the production of three dimensional images from any two dimensional information medium or surface. With the foregoing in mind, the present invention provides a 3D information image display system comprising a first order reflective surface arranged substantially perpendicular to and between a pair of stereo images, one image of which is reversed left to right, wherein a viewer, directing his line of sight towards the stereo image behind the reflective surface and positioned such that one eye views the stereo image behind the reflective surface directly and the other eye views the other stereo image reflected by the reflective surface, can readily appreciate the 3D information provided by the stereo images. As will be understood, the viewer simply needs to look with both eyes in a particular direction to view the three dimensional image. The quality of such an image is surprisingly good and is not dependent upon the viewer being perfectly positioned relative to the reflective surface - the viewer can move around a significant amount without losing the 3D image. Ideally the stereo images lie in a first plane and the reflective surface is positioned midway between the images. Such an arrangement is very simple, yet produces excellent results. However, in theory the relative positions of the components could be altered, if required in a particular application. Preferably the plane in which the stereo images lie is flat. As a result, excellent quality three dimensional images can be produced. Alternatively, the stereo images could lie on oppositely inclined surfaces or on a curved surface, or one of the images could lie on a curved surface and the reflective surface could be appropriately curved to negate the resulting curvature of the image. Other arrangements can of course be envisaged, without departing from the present invention. Preferably the reflective surface is spaced from the plane in which the stereo images lie. By arranging the reflective surface in this way, the vision of a viewer is not complicated by information produced at the corner between the reflective surface and the plane in which the stereo images lie, especially when the reflective surface is less than perfect quality. The height of the top of the reflective surface is preferably designed to be at a distance above the plane of the images that does not compromise an average person's visual near point (which is about 22cm (9 inches) from image to eye) . As a result, comfortable viewing of the 3D information can be readily achieved. If the stereo images lie in a single flat plane and the reflective surface is perpendicular to that plane, visual information from the stereo image in front of the reflective surface must travel further to the viewer's eye than the visual information from the stereo image behind the reflective surface. As a result, it may be preferable to magnify (perhaps by 5%) the stereo image in front of the reflective surface. Additionally or alternatively, the stereo image in front of the reflective surface may simply be brighter than that behind the reflective surface, so that the visual images reaching the viewer's eyes are as clear from both the front and rear stereo images. Preferably the reflective surface is a front surface mirror. A protective coating may be applied to the mirror, to avoid the mirror becoming damaged in any way. The mirror is front surfaced to avoid any possibility of a double reflection occurring due to the surface of a transparent sheet in front of the mirror surface. The reflective surface (or mirror) preferably tapers away from the stereo images. This is because the reflective surface needs only to transfer visual information from the stereo image in front of the reflective surface into the viewer's eye, and this information will clearly need to converge towards the eye. Hence, sharp corners on the mirror can be removed, and the edges of the mirror can be bevelled for safety, without affecting the efficiency of the reflective surface. If the tapering of the reflective surface is curved, an even safer mirror can be produced. The display system can be formed in a multitude of different ways, provided that the basic requirement of the reflective surface being arranged substantially perpendicular to and between a pair of stereo images is satisfied. Hence, the reflective surface can be supported in a boot or clip between the stereo images. Alternatively, a stanchion could be used for supporting, in a cantilevered fashion, the reflective surface so that the reflective surface is positioned substantially perpendicular to and between a pair of stereo images. Many other arrangements can, of course, be envisaged. The means for supporting the reflective surface and the reflective surface itself are preferably handed to ensure that the reflective surface faces the correct one of the pair of stereo images. If the reflective surface faces the wrong stereo image, the viewer would need to look the other way and the three dimensional image viewed by a viewer will be reversed left to right. In an environment where the 3D information needs to be viewed from any direction, such as in a large museum or shop display, the mirror may be double sided. Although the image would be reversed left to right when approached by a viewer from one direction, this should not be a problem provided that the image does not include letters or numerals but is simply a picture. In a particularly preferred embodiment, the stereo images are printed in a book. The images will be printed either on the same page of the book or on adjacent facing pages, so that the reflective surface can be positioned between the two stereo images. If such an arrangement is used, the book may be manufactured in the form of a ring binder so that the pages of the book lie as flat as possible. In alternative embodiments, the stereo images may be displayed on video screens, television screens or any other flat or curved display surface, such as video monitors, LCDs, computer processors, etc. The stereo images may be static images or, alternatively, moving images. Specific embodiments of the present invention are now described, by way of example only, with reference to the accompanying drawings, in which:- Figure 1 is a schematic perspective view of a first embodiment of a display system according to the present invention; Figure 2 is a schematic side view showing the optical paths from the stereo images to a viewer's eyes; and Figure 3 is a schematic perspective view of a second display system according to the present invention. A three dimensional (3D) information image display system 1 according to the present invention is shown in Figure 1 of the drawings. The system 1 comprises an inclined viewing surface 3 formed on an inclined platform 5, two supplies 7a, 7b of stereoscopic images 8a, 8b and a reflective surface 9 substantially perpendicular to and midway between the stereo images 8a, 8b. Although not shown, the inclined platform 5 may incorporate means for adjusting the angle of inclination of the viewing surface 3. In the Figure, the stereo images 8b of the right hand supply 7b have been reversed left to right so that, when viewed after reflection by the reflective surface 9, appear consistent with the left hand supply 7a of stereo images 8a. Each supply 7a, 7b of stereo images 8a, 8b is held together by means of a ring binder 11 and attached to the platform 5 by means of clips 13. The stereo images 8a, 8b can therefore be flipped into position in pairs from the supplies 7a, 7b and can lie substantially flat against the viewing surface 3 of the platform 5. Furthermore, when a particular supply 7a, 7b of stereo images 8a, 8b is no longer required, it can be replaced by a fresh supply. Likewise, ring bound text 15a, 15b can be accommodated on the viewing surface 3, so that information relating to a particular stereoscopic image can be readily accessed by a user of the display system 1. The reflective surface 9 is a front surface mirror, supported by a rigid substrate 17. The substrate 17, which may simply be a rigid plastics sheet, is received in a boot or recess 19 formed in the inclined platform 5 with a tight fit. As a result, the position of the reflective surface 9 is accurately defined. As can be seen in Figure 1, the upper corners of the support substrate 17 have been removed to avoid any danger to a user of the display system 1. If it is considered necessary, an inclined line can be marked on the support substrate 17 to indicate to a user of the display system 1 the orientation in which the support substrate 17 should be entered into the boot 19 in the platform 5. As a result, the reflective surface 9 should always end up facing towards the correct stereo image 8b. In order to use the display device 1 shown in Figure 1, a viewer positions his nose adjacent the edge of the reflective surface 9 as shown in Figure 2. As can be seen, one eye 21 of the viewer views directly the left stereo image 8a, whereas the other eye 23 views the right hand stereo image 8b after it has been reflected by the reflective surface 9. As a result, the viewer can use normal vision to appreciate easily the three dimensional information contained in the two stereoscopic images 8a, 8b. This is a distinct improvement in both comfort and simplicity of apparatus over the known prior art systems. Furthermore, such a display system 1 is remarkably tolerant as regards the exact positioning of the viewer and any movement of the viewer during viewing. Although not shown in Figure 1, if necessary the stereo images 8a, 8b could be back lit or front lit, as required. Further, the angle of inclination of the viewing surface 3 could be adjustable to enable a viewer to use the display system 1 more comfortably. Turning now to Figure 3 of the drawings, a second embodiment of display system 1 according to the present invention is shown. In this embodiment, the reflective surface 9 is supported by a stanchion 30 mounted on a support base 32. The support base 32 includes a fence 34 against which a ring bound book 36 abuts to position accurately the stereo images 8a, 8b either side of the reflective surface 9. In such an embodiment, the support base 32, stanchion 30 and reflective surface 9 can be purchased as one unit with the ring bound books 30 purchased separately, as required. Other arrangements of equipment and sources of stereo images 8a, 8b, which enable the present invention to be put into practice can, of course, be envisaged by those skilled in the relevant art. For example, the cover of a book may accommodate a boot or clip for receiving a mirror, with the mirror being supplied with the book and carried in a pocket therein or purchased separately, as required. With this in mind, if a high quality mirror is used, when extremely detailed stereoscopic images are being viewed, this is likely to be purchased separately and stored carefully. Cheaper mirrors may be used for less detailed stereoscopic images or when children are using the equipment, for example. Although the invention has been described with reference to a single reflective surface, in theory the stereo images could be separated by a double sided mirror. A user could then either look left or right to see the 3D information, although clearly one of the views would reveal the image reversed. It will of course be understood that the present invention has been described above purely by way of example, and that modifications of detail can be made within the scope of the invention.

Claims: CLAIMS 1 . A 3 D information image display system comprising a first or d er reflective surface arranged substantially perpen d icular to and between a pair of stereo images, one of which is reversed left to right, wherein a viewer, d irecting his line of sight towards the stereo image b ehin d the re f lective surface and positioned such that one eye views the stereo image behind the reflective surface d irectly an d the other eye views the other stereo image re f lecte d b y t h e reflective surface, can readily appreciate the 3 D information provided by the stereo images. 2 . A display system as claimed in claim 1 , wherein the stereo images lie in a first plane and the reflective surface is positioned midway between the images. 3 . A display system as claimed in claim 2, wherein the first plane is substantially flat. 4 . A display system as claimed in claim 2 or claim 3 , wherein the reflective surface is spaced f rom the f irst plane. 5. A display system as claimed in claim 2, claim 3 or claim 4 wherein the first plane can be supported at a variety of angles of inclination. 6 . A display system as claimed in any prece d ing claim, wherein the stereo image in front of the reflective surface is magnified relative to the stereo image b ehin d the reflective surface. 7 . A display system as claimed in any preceding claim, w h erein the stereo image in front of the reflective surface is brighter than the stereo image behind the reflective surface. 8. A display system as claimed in any preceding claim, wherein the reflective surface is a front surfaced mirror. 9. A display system as claimed in any preceding claim, wherein the rear of the reflective surface is also reflective. 10. A display system as claimed in any preceding claim, wherein the reflective surface tapers away from the stereo images. 11. A display system as claimed in claim 10, wherein the tapering is curved or bevelled or both. 12. A display system as claimed in any preceding claim, wherein the reflective surface extends to a height above the stereo images which ensures that an average person's near point is not compromised. 13. A display system as claimed in any preceding claim, wherein support means carry the reflective surface. 14. A display system as claimed in claim 13, wherein the support means and the reflective surface are handed to ensure correct positioning of the reflective surface. 15. A display system as claimed in claim 13 or claim 14, wherein the support means comprise a boot or clip. 16. A display system as claimed in claim 13 or claim 14, wherein the support means comprise a stanchion. 17. A display system as claimed in any one of claims 13 to 16. wherein the support means provide a base for the stereo images. 18. A display system as claimed in claim 17, wherein the support means dictate the position of the stereo images relative to the reflective surface. 19. A display system as claimed in any preceding claim, wherein the stereo images are printed in a book. 20. A display system as claimed in claim 19, wherein the book is in the form of a ring binder or several ring binders such that a number of pages can be turned separately. 21. A display system as claimed in any one of claims 1 to 18, wherein the stereo images are back lit or displayed on a video screen. 22. A display system as claimed in any preceding claim, wherein the stereo images are moving images. 23. A 3D information image display system substantially as hereinbefore described with reference to and as shown in the accompanying drawings. 24. An information storage medium containing a plurality of pairs of stereo images, one stereo image in each pair being reversed, for use in a display εystem as claimed in any preceding claim. 25. An information storage medium as claimed in claim 24, wherein the medium is a book, a video compact disc or any other appropriate information storage medium or display surface. 26. An information storage medium substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

Inventors: PARKS CHRISTOPHER PETER, PARKS PETER DENISON, PARKS, CHRISTOPHER, PETER, PARKS, PETER, DENISON
Applicants: IMAGE QUEST LIMITED, PARKS CHRISTOPHER PETER, PARKS PETER DENISON, PARKS, CHRISTOPHER, PETER, PARKS, PETER, DENISON
Application year: 1997
Main classification: G02B27
IPC codes: G02B27