SIMULATED THREE-DIMENSIONAL IMAGING SYSTEM

Abstract: A method for the simulated three-dimensional imaging of an object, comprises the steps of a) creating, simultaneously or sequentially, first and second panoramic images (25, 25a) of the object from two spatially separated positions offset from a common axis of rotation, b) conveying the first and second images (25, 25a) simultaneously to the viewer's right and left eyes separately, and c) moving the first and second images (25, 25a) in synchronism or near-synchronism in response to, or in simulation of, movement of the viewer's head. There are also described systems for creating the images (25, 25a) in step a), and for viewing the images so created.

Description: Title : Simulated Three-Dimensional Imaging System This invention relates to apparatus and methods for the creation and viewing of three-dimensional images of real or simulated objects. Methods of simulated three-dimensional photography are known. Conventionally, a three-dimensional photograph is created by taking two photographs of the same object from points separated in space by a distance comparable with the separation of human eyes. The two photographs are then viewed separately, but simultaneously, by the viewer's right and left eyes. This creates an illusion of three-dimensional depth. A shortcoming of conventional three-dimensional photography methods of this kind is that the viewer inevitably has the perception of being outside the object, looking in. The technique thus does not provide the viewer with the perception of being inside the object or three-dimensional space being viewed. Virtual Reality is the name given to technology with which a viewer can achieve this effect. Typically, a Virtual Reality system comprises a headset with two small display screens viewed separately by the viewer's right and left eyes. The position and orientation of the viewer's head are sensed and the images displayed on the screens changed accordingly. Such Virtual Reality systems suffer from the disadvantage that the images are of low quality, even though the systems are relatively expensive. There have now been devised methods and apparatus for simulated three-dimensional imaging of an object or three- dimensional space (hereinafter referred to as "object") which overcome or substantially mitigate the above-mentioned disadvantages. According to a first aspect of the present invention, there is provided a method for the simulated three-dimensional imaging of an object, which method comprises a) creating, simultaneously or sequentially, first and second panoramic images of the object from two spatially separated positions offset from a common axis of rotation, b) conveying the first and second images simultaneously to the viewer's right and left eyes separately, and c) moving the first and second images in synchronism or near-synchronism in response to, or in simulation of, movement of the viewer's head. The first and/or second images may be real images or simulated images. Real images may be panoramic photographic images. Simulated images may be generated using a computer. Real or simulated images of high quality may both be easily produced. In all cases, the images are preferably positive images so that they may be viewed directly. The images may be recorded using a system according to a second aspect of the invention, which provides a simulated three-dimensional imaging system comprising first and second objective means spatially separated about a common axis of rotation, means for rotating the first and second objective means relative to the object in synchronism, and first and second recording means for separately recording panoramic images produced by the first and second objective means respectively. The first and second objective means may be the objective lenses of panoramic still photography cameras or of video cameras. The first and second recording means may be panoramic photographic films or plates, or may be video tapes or other long-term storage media. Instead of recording the images simultaneously, for some applications it may be possible to record the images sequentially. For example, a single panoramic camera of conventional form may be used with a mirror attachment to offset the camer 'a optical axis first to one side and then, for recording the second image, to the other side. The recorded images may be viewed using apparatus according to a third aspect of the present invention, which provides a system for the simulated three-dimensional viewing of an object, comprising first and second display means for simultaneously displaying first and second panoramic images respectively of the same object taken from positions spatially separated about a common axis of rotation, means for conveying the first and second images separately to the right and left eyes of a viewer, and means for moving the first and second images in synchronism or near-synchronism in response to, or in simulation of, movement of the viewer's head. The first and second display means may, where the images are panoramic photographic images, simply be suitable means for illumination of the images. The means for conveying the images to the viewer's eyes may be, for example, systems of lenses and/or mirrors. The means for moving the first and second images may be mechanical, eg systems of rollers for shifting panoramic photographic images synchronously. In a preferred embodiment of the viewing system, the images take the form of films or strips which are moved in synchronism by simple mechanical devices. Such a viewing system has the advantages of ease of use and low cost. For many applications, it is preferred that the images be stored in cassettes which can easily and quickly be installed in a viewing system. To enable the images to be moved in response to movements of the viewer's head, position sensors may be used, eg as in known Virtual Reality headsets. Appropriate sounds may be synchronised with movement of the images, eg through an audio headset. The panoramic images may be full panoramic images, taken through 360°, or may be only partial panoramic images taken through less than 360°, eg 180° or less. Where the images are full panoramic images, they may be in the form of loops. For some applications it may be preferable for the images to be taken through more than one, eg two or three, complete rotations. Where the images are recorded on photographic films, for example, this may enable a full panorama to be viewed without encountering a join in the film loop. For most applications, it is preferable that the images are taken, or appear to be taken, from positions the separation of which corresponds to the separation of the human eyes, ie about 70mm. This will give the most realistic three- dimensional effect. However, other effects may be achieved by appropriate choice of the spatial separation of the first and second objective means, or of the points from which simulated images are apparently taken, or of the objective lens magnification. Areas of application of the methods and apparatus of the present invention include the following: Recreation - providing Virtual Reality using low cost viewing systems. Video games could combine this technique with cheap televisual output. Marketing - purchasers, eg of houses or offices, could view the inside of a building without visiting it. Design - architects could present computer-based designs, both interior and exterior, for proposed buildings. Education and training - providing realistic teaching aids using real or simulated images, eg of the inside of the body, astronomical bodies etc. Exhibitions - for example to provide displays of a company's work. Documentary purposes - providing accurate records of, for instance, scenes of crime. The invention will now be described in more detail, by way of illustration only, with reference to the accompanying drawings, in which Figure 1 is a schematic view of a panoramic camera system according to the invention; Figure 2 is a schematic view of a viewing system according to the invention; Figure 3 is a schematic view of a second panoramic camera system according to the invention, utilising only one camera, Figure 4 is a side view of a second, floor-mounted, viewing system according to the invention; Figure 5 is a sectional view along line V-V of Figure 4; Figure 6 is a side view of a third, suspended, viewing system according to the invention; Figure 7 is a schematic plan view of a fourth viewing system according to the invention, in the form of a headset; Figure 8 is a side view of the headset of Figure 7; and Figure 9 is a schematic plan view of a fifth viewing system according to the invention. Referring first to Figure 1, a panoramic camera system comprises a pair of panoramic photographic cameras 1,2, each being of generally conventional design. The two cameras 1,2 have respective objective lenses 3,4 and are mounted side-by- side for rotation about an axis 5 between them. The separation of the objective lenses 3,4 is similar to the separation of human eyes, ie about 70mm. The cameras 1,2 are loaded with conventional transparency film. In use, the camera assembly is rotated about the axis 5, each camera recording a conventional full panoramic transparency. The camera assembly may be rotated through one complete 360° rotation or through multiple rotations, eg two or three rotations. The films from the cameras 1,2 are processed in the conventional way and formed into loops. Referring now to Figure 2, a viewing apparatus is shown with which the transparencies recorded with the camera system of Figure 1 may be viewed. The viewing apparatus comprises an enclosed housing 21 containing a transport mechanism 22,22a for each transparency 25,25a. Each transport mechanism 22,22a comprises a set of three rollers 27,27a about which the respective transparencies 25,25a are mounted. The rollers 27,27a are provided with sprockets (not shown) which engage in marginal sprocket holes in the transparency loops 25,25a. Each transparency 25,25a is backlit by a lamp 26,26a, corresponding portions of the transparencies 25,25a being viewed through an arrangement of viewing lenses 24,24a and mirrors 23,23a. The portion of each transparency 25,25a which is viewed follows a curved track defined by appropriate guides. The optimum radius of curvature is a function of the length of film corresponding to one complete 360° rotation. Specifically, the optimum radius is that length divided by 2π. The transparencies 25,25a are moved in synchronism by means of a knob (not shown) on the underside of the housing 21. he knob is coupled by an appropriate gear train to one of ~ h set of rollers 27,27a, the remaining rollers being freely rotatable. In use, the user holds the housing to his face and looks through the viewing lenses 24,24a and sees a simulated three- dimensional image. Synchronised movement of the transparencies 25,25a simulates the effect of rotation of the user's head, the user having the perception of being inside the viewed object. Turning now to Figure 3, there is shown a schematic view of a camera system analogous to that of Figure 1, but employing only a single panoramic camera 31. As shown in Figure 3(a), the camera is mounted for rotation about an axis 32. An attachment 33 is fitted to the front of the camera 31, the attachment 33 including a pair of mirrors 34,35 arranged effectively to displace the optical axis of the camera 31 to the right by 35mm. In Figure 3(b) the attachment 33 is shown inverted. In this arrangement, the optical axis of the system is displaced 35mm to the left. Thus, by using the camera 31 twice, first with the attachment 33 in the position shown in Figure 3(a) and then in the position shown in Figure 3(b), two panoramic transparencies such as those generated simultaneously by the camera system of Figure 1 may be created. Of course, because the two images are not created simultaneously, the system of Figure 3 is generally only suitable for photographing static objects. A second embodiment of a viewing system is shown in Figure 4. This comprises a viewer unit 41 rotatably mounted on a pole 42 extending upwards from a fixed base 43. The viewer unit 41 is provided with a pair of handles 44 which are gripped by the user when looking into the viewer unit 41. As can be seen from Figure 5, the viewer unit 41 contains two transparency loops 51,51a which pass around sets of rollers 52,52a. As in the system of Figure 2, the portions 53,53a of the transparencies 51,51a which are viewed are backlit by lamps 54,54a and formed into curves. The transparencies 51,51a are viewed through a pair of lenses 55,55a. Fixedly mounted on the top of the pole 42 is a sun gear 56. Planetary gears 57,57a are fixed coaxially with the rearmost of each set of rollers 52,52a. In use, the user grips the handles 44 and views the transparencies 51,51a through the lenses 55,55a. The viewer unit 41 can be freely rotated. As rotation occurs, the planetary gears 57,57a orbit the sun gear 56, causing synchronised movement of the transparency loops 51,51a. Once again, the user has the impression of being inside the object. Figure 6 shows a similar system to that of Figures 4 and 5, with the exception that the viewer unit 61 is suspended from a ceiling. Again, the viewer unit 61 is freely rotatable about a sun gear (not shown) fixed to the bottom of the suspension member 62. It will be appreciated that the suspension member 62 could be replaced by any member capable of maintaining a fixed orientation of the sun gear as the viewer unit is rotated. In the embodiments of Figures 4 to 6, the problem of maintaining a fixed reference point is solved by a fixed mechanical connection to the floor or ceiling respectively. Figures 7 and 8 illustrate an alternative approach. These show a headset comprising once again a pair of panoramic transparency loops 71,71a mounted about rollers 72,72a. As in the viewing systems previously described, there are provided viewing lenses 73,73a and the portions of the transparencies which are viewed are backlit by lamps 74,74a and curved. The transparency loops 71,71a are driven by a sun gear 75 which meshes with planetary gears 76,76a mounted on the axles of one of each set of rollers 72,72a. The sun gear 75 is driven via a gear train by a servo motor 77 under the control of a gyroscope 78 fixedly mounted on the sun gear 75. Power and control of the motor 77 and lamps 74,74a is provided by a battery and circuit pack 79 mounted on the back of the headset. Movement of the headset is sensed by the gyroscope 78, whereupon the servo motor 77 is actuated to realign the sun gear 75 and thereby to rotate the transparency loops 71,71a in synchronism. As alternatives to the gyroscope 78, other forms of direction sensor may be used. Examples are sensors, eg infra-red sensors, able to detect radiation from a source fixed in the surrounding space, compasses, etc. Finally, Figure 9 shows schematically a viewing system in the form of a booth. The user sits on a swivel stool 91 above which, approximately at eye level, is fixed an annular gear track 92. A viewer unit 93 is mounted for orbital motion around the track 92. The internal construction of the viewer unit 93 is broadly similar to that of the systems previously described, the difference being that the transparency strips 94,94a are driven by gears 95,95a meshing with the annular track 92. In use, the user sits on the stool 91 and holds the viewer unit 93 to his eyes. As the user swivels on the stool 91, the viewer unit 93 follows around the track 92, the transparencies 94,94a again being moved in synchronism.

Claims: Claims 1. A method for the simulated three-dimensional imaging of an object, which method comprises a) creating, simultaneously or sequentially, first and second panoramic images (25,25a) of the object from two spatially separated positions offset from a common axis of rotation, b) conveying the first and second images (25,25a) simultaneously to the viewer's right and left eyes separately, and c) moving the first and second images (25,25a) in synchronism or near-synchronism in response to, or in simulation of, movement of the viewer's head. 2. A method as claimed in Claim 1, wherein the first and/or second images (25,25a) are real images. 3. A method as claimed in Claim 2, wherein the images (25,25a) are panoramic photographic images. 4. A method as claimed in Claim 1, wherein the first and/or second images are simulated images. 5. A method as claimed in Claim 4, wherein the images are generated using a computer. 6. A method as claimed in any one of the preceding claims, wherein the images (25,25a) are positive images. 7. A method as claimed in any one of the preceding claims, wherein the panoramic images (25,25a) are full panoramic images. 8. A method as claimed in Claim 7, wherein the panoramic images are taken, or appear to be taken, through more than one complete rotation. 9. A method as claimed in any one of the preceding claims, wherein the images (25,25a) are taken, or appear to be taken, from positions the separation of which corresponds to the separation of the human eyes. 10. A method as claimed in any one of the preceding claims, wherein the images (25,25a) are recorded simultaneously. 11. A method as claimed in any one of Claims 1 to 9, wherein the images (25,25a) are recorded sequentially. 12. A simulated three-dimensional imaging system comprising first and second objective means (3,4) spatially separated about a common axis of rotation (5) , means for rotating the first and second objective means (3,4) relative to the object in synchronism, and first and second recording means for separately recording panoramic images produced by the first and second objective means (3,4) respectively. 13. A system as claimed in Claim 12, wherein the first and second objective means (3,4) are the objective lenses of panoramic still photography cameras or of video cameras. 14. A system as claimed in Claim 12 or Claim 13, wherein the first and second recording means are panoramic photographic films or plates. 15. A system as claimed in Claim 12 or Claim 13, wherein the first and second recording means are video tapes. 16. A system for the simulated three-dimensional viewing of . an object, comprising first and second display means (26,26a) for simultaneously displaying first and second panoramic images (25,25a) respectively of the same object taken from positions spatially separated about a common axis of rotation. means (23,23a,24,24a) for conveying the first and second images (25,25a) separately to the right and left eyes of a viewer , and means (22,22a) for moving the first and second images (25,25a) in synchronism or near-synchronism in response to, or in simulation of, movement of the viewer's head. 17. A system as claimed in Claim 16, wherein the images (25,25a) are panoramic photographic images, and the first and second display means (26,26a) are suitable means for illumination of the images. 18. A system as claimed in Claim 16 or Claim 17, wherein the means for conveying the images (25,25a) to the viewer's eyes comprise lenses (24,24a) and/or mirrors (23,23a). 19. A system as claimed in any one of Claims 16 to 18, wherein the means (22,22a) for moving the first and second images (25,25a) are mechanical. 20. A system as claimed in any one of Claims 16 to 19, wherein the images (25,25a) take the form of films or strips which are moved in synchronism by simple mechanical devices. 21. A system as claimed in any one of Claims 16 to 20, wherein the images are stored in cassettes which can easily and quickly be installed. 22. A system as claimed in any one of Claims 16 to 21, further comprising a position sensor (78) to detect movements of the viewer's head. 23. A system as claimed in any one of Claims 16 to 22, wherein the images (25,25a) are real photographic images and the portion of each which is viewed follows a curved track, the radius of curvature being the length of film corresponding to one complete 360° rotation divided by 2π. 24. A system as claimed in any one of Claims 16 to 23, comprising a viewer unit (41) rotatably mounted on a fixed base (43), the viewer unit (41) containing a fixed sun gear (56) and a pair of planetary gears (57,57a) operably linked to a pair of real panoramic images (53,53a) such that as rotation occurs the planetary gears (57,57a) orbit the sun gear (56) causing synchronised movement of the images (53,53a). 25. A system as claimed in any one of Claims 16 to 23, comprising a rotatable, suspended viewer unit (61), the viewer unit (61) containing a fixed sun gear and a pair of planetary gears operably linked to a pair of real panoramic images such that as rotation occurs the planetary gears orbit the sun gear causing synchronised movement of the images. 26. A system as claimed in Claim 22, in the form of a headset. 27. A system as claimed in any one of Claims 16 to 23, comprising a viewer unit (93) mounted for orbital motion around the internal rim of an annular gear track (92), the viewer unit (93) containing means for displaying a pair of panoramic images (94,94a), said means being operably linked to the gear track (92) to bring about synchronised movement of the images (94,94a) as orbital motion of the viewer unit (93) occurs. 28. A camera system for the sequential recording of panoramic photographic images comprising means (33) for offsetting the optical axis a fixed distance from the axis of rotation (32) of the camera (31), first in one direction and then in a second, diametrically opposite direction.

Inventors: KEW MICHAEL JEREMY, KEW, MICHAEL, JEREMY
Applicants: KEW MICHAEL JEREMY, KEW, MICHAEL, JEREMY
Application year: 1992
Main classification: G02B27
IPC codes: G02B27, G03B35, H04N13