WO2006077324A1

WO2006077324A1 - Two-screen three-dimensional image display system

Info

Publication number: WO2006077324A1
Application number: PCT/FR2006/000123
Authority: WO
Inventors: Patrick Levy-Rosenthal
Original assignee: 3Dsolar Ltd.
Priority date: 2005-01-20
Filing date: 2006-01-19
Publication date: 2006-07-27
Also published as: FR2880955A1

Abstract

The invention relates to a system for reproducing three-dimensional images. The inventive system comprises: a first screen (10; 100) and at least one second screen (10; 110<SUB>1</SUB>) which receives and reproduces images, said two screens being disposed at a distance from one another; an optical device (20, 22; 38<SUB>1</SUB>) for producing an image from the screens in space (18); and synchronising means that synchronise the nature of the images produced at the spatial position (12, 12') of the viewer relative to the system such that, on the one hand, the image remains in the field of vision of the viewer and, on the other hand, the angle of view of the image obtained on the screens corresponds to the position of the viewer, in particular, that of the viewer's face.

Description

IMPROVEMENTS TO A SYSTEM OF VISUALIZATION OF IMAGES IN

RELIEF

The invention relates to a system for viewing or restoring images in relief, allowing the observation of scenes from various angles.

The systems for displaying three - dimensional or relief images are of various kinds: hologram systems, systems requiring the wearing of spectacles, Fresnel lens system, etc.

The invention starts from the observation that these known systems do not allow spectators to see without effort the scene represented at various angles and along several axes. By "scene" we mean here any element: one or more objects, one or more characters, one or more animals, plants, landscapes, etc.

The invention provides a three - dimensional image generation system for performing this function.

Thus, the system according to the invention comprises: - a mobile screen receiving and projecting images, a means for producing an image of the screen providing a relief impression, and. synchronization means for adjusting the position of the screen and the projected images according to the position in the spectator space with respect to the system.

In these conditions, if the images appearing on the screen come from computer means containing or receiving images of a scene taken from various angles of view, the synchronization means provide the images corresponding to the position of the spectator and ensure a displacement of the screen so that the viewer always keeps the vision of the image.

In one embodiment, the images taken from various angles of view are extracted from a memory.

In another embodiment, the images arriving on the screen come from shooting means that can capture images of the scene from various angles depending on the position of the viewer.

The synchronization means are for example such that the viewing angle of the projected image varies in proportion to the movement of the viewer. In one embodiment, the viewing angle of the projected image varies more than the viewer 's movement to minimize viewer movement relative to the system.

In one embodiment, the system includes shooting means, such as at least one camera, for monitoring in real time the position of the viewer in the space. The position of the viewer is determined by the position of a part of his body, preferably at least one of the following parts: the eyes, the nose, the hands, the feet.

For the detection of a part of the body, it is possible for example to use the software products distributed by the Australian company Seeing Machines.

According to one embodiment, the system comprises, on the one hand, means for detecting a part of the face such as the eyes or the nose and, on the other hand, means for detecting another part of the spectator 's body. , including his hand, or both hands. In this case, preferably, the detection means of the hand (or other part of the body) of the viewer detect the presence of the hand in the area where the viewer sees the relief image and, the system comprises means for making interacting with these means for detecting the hand with means for creating or selecting images. Thus, for example, a pressure of the hand in the area where there must be an object which, when it is real, is soft, causes a deformation of this object, or a gesture causes the displacement of the object. In general, the interaction between the hand, or other part of the body, and the scene may change other parameters of the virtual scene, for example its color or texture.

Thus, the interaction between the viewer and the virtual scene seen in relief (that is to say the synchronization of the nature of the images produced and the position of the screen at the position in the space of the viewer relative to to the system) is carried out in two ways: in the first way, the movement of the viewer, especially his face, causes the representation of a different angle of view of the virtual scene. For example, if the viewer moves from sitting to standing, the viewer moves from a front view of an object to a top view of that object. In the second way, a gesture of the hand involves a modification or a displacement of a virtual object.

The applications of the system according to the invention are numerous. Some examples are: television, video, cinematographic films and computer science. In particular, the invention can be used for the presentation of virtual objects, especially for sale, whether in a store or in distribution, in particular by the Internet type network.

The invention can also be applied to videoconferencing. So, in one embodiment of the applied system at videoconferencing, at least one of the interlocutors is expected to have a system of the type defined above, and this system, which is in a first location, includes means for providing a signal representing the position of the viewer and means for transmitting said viewer position signal to photographing means at the second location where the second interlocutor is located, said shooting means providing the viewing angle of the second interlocutor corresponding to the second speaker; angle desired by the position (especially eyes) of the viewer at the first location. For example, a camera of the second interlocutor (at the second location) moves to provide at the first location, an angle of view of the second interlocutor which corresponds to the angle desired by the first interlocutor. In a variant, to avoid the displacement of a transmitting camera, the system comprises, at one location, two camera cameras of the interlocutor which simultaneously send their images from two different angles in the system of relief vision. located at the other location, and at this other location, the system includes means for reconstructing the 3D image of the second party. Note however that in this embodiment, twice as much information is transmitted on the line between the two interlocutors as in the first embodiment of videoconferencing systems. Whatever its application in the system according to the invention, the relief effect can be obtained in various ways.

According to one embodiment, an optical device, such as a mirror or a set of mirrors, is associated with the screen, which returns the image of the screen to a position of the space to which the viewer 's gaze is directed.

In this case, the system comprises, for example, means for modifying separately the position of the screen and the position of the optical device. In a variant, the screen and the optical device are integral with a housing or frame and have a fixed position relative to the housing or chassis which is provided with control means to rotate it, for example, along two orthogonal axes. When the optical device comprises at least one mirror, the latter is shaped, for example, spherical or parabolic.

The invention thus relates to a system for restoring three - dimensional images, comprising: a mobile screen receiving and reproducing images,

an optical device for producing an image of the screen in the space, and

means for synchronizing the nature of the images produced and the position of the screen at the position in the spectator 's space with respect to the system, so that, on the one hand, the image always remains in the field of view; viewer 's vision and, on the other hand, that the angle of view of the image obtained on the screen corresponds to the position of the viewer, in particular that of his face. In one embodiment, the system comprises means for changing the angle of view of the image to be rendered according to the movement of the viewer, the modification of the viewing angle being, for example, proportional to the movement of the viewer. The system preferably includes camera means for detecting, in real time, the position of the viewer in the space.

According to one embodiment, the system comprises a memory in which a plurality of images of the same scene are stored in a plurality of viewing angles, the synchronization means being such that they restore the image corresponding to the angle viewpoint associated with the viewer's position.

In a variant, the system comprises means for shooting a controlled scene, thanks to the synchronization means, to take the image of the scene according to an angle of view which corresponds to the position of the spectator.

In this case, the shooting means of the scene can be movable according to the position of the spectator.

As a variant, the imaging means comprise at least two cameras or the like to provide two angles of view of the same scene, the synchronization means comprising processing means for restoring, from the two angles of

10 view, the viewing angle corresponding to the position of the viewer.

The system constitutes, in one embodiment, a system that can be used for videoconferences, and includes a means of shooting intended to restore, for a remote party, the image of the party using the system.

In one embodiment, the synchronization means comprise, on the one hand, means for detecting the position of the face of the spectator, or part of this face, in particular the eyes, and, on the other hand, means for detecting another part of the viewer 's body such as the hands or the feet, and processing means so that the appearance or the displacement of this other part of the body causes a modification of the image obtained in three. dimensions, this modification being, for example, a displacement, a deformation or a change of texture or color. The optical diαpocitive is, for example, fixed position.

In a variant, the system comprises a frame of which is secured, on the one hand, the screen and, on the other hand, the optical device, the screen and the optical device being fixed relative to this frame, the synchronization means including

30. means for changing the position of the chassis.

Preferably, the optical device comprises at least one spherical or parabolic mirror.

The improvements according to the present invention are intended to make it possible to present an extended scene in depth or to present multiple objects at different distances from the viewer.

Thus, the improvements according to the invention relate to a system for restoring three-dimensional images comprising:

a first screen and at least one second screen receiving and reproducing images, these two screens being at a distance from one another, an optical device for producing an image of the screens in the space, and

means for synchronizing the nature of the images produced at the position in the spectator 's space with respect to the system, so that, on the one hand, the image remains in the spectator' s field of view and, on the other hand, , that the angle of view of the image obtained on the screens corresponds to the position of the spectator, in particular that of his face.

In one embodiment, the second screen is closer to the optical system than the first screen and is substantially parallel to the first screen, and portions of the second screen that do not produce images are transparent. The second screen is for example organic electroluminescent diodes. According to one embodiment, the system comprises control means so that the images appear simultaneously on the two screens. In a variant, the system comprises control means for the images to appear at different times on the two screens, the frequency of appearance being sufficiently high for the spectator, by the retinal persistence, to simultaneously see the images of the two screens. In one embodiment, the system comprises computer processing means which comprise image generating means, for example memory means, and means for assigning each part of an image to a screen according to the relative distance of this part to the image. spectator. According to one embodiment, the system comprises computer processing means for effecting a correction of the geometry of the images as a function of the position in the space of the viewer with respect to the system and / or according to the position of the screen relative to to the optical device, these computer processing means performing a geometric correction for correcting the deformations caused by the different distances of the screens.

Other characteristics and advantages of the invention will become apparent with the description of some of its embodiments, this being done with reference to the attached drawings in which:

FIG. 1 is a diagram of an embodiment of a system according to the invention; FIGS. 2 and 3 are diagrams of another embodiment of the invention;

FIG. 4 is a diagram of a use of a system according to the invention, and

- Figure 5 is a diagram of a variant of the system according to the invention.

In the example shown in Figure 1, the system according to the invention comprises a screen 10 on which are formed ^"of a computer from image (not shown) or line provided by a television system such as that of a videoconference. The screen is, for example, of the liquid crystal, plasma or cathode ray type.

On the screen are associated image - generating means which provide views of a scene which are a function of the position of a spectator, in particular of the position of the face and more particularly of his eyes 12.

The screen 10 is secured to a vertical support 14 which is associated with a control means for rotating the support about its axis. In addition, the screen 10 is movable about a horizontal axis 16, by a hinge or support 14, by means of second control means. These first and second control means adjust the position of the screen 10 according to the position of the viewer 12 so that the three-dimensional virtual image, 18, seen by the viewer 12 remains in the field of view of the latter. The system comprises an optical device which comprises, in the example, two parabolic mirrors 20 and 22. When the viewer is in the position 12 shown in FIG. 1 and when the screen is in the position 10 shown in solid lines , the image on the screen is reflected on the upper part 24 of the parabolic mirror 20 and is then reflected on the lower part 26 of the same mirror 20 to focus at the location 18.

When the viewer moves from position 12 to position 12 ', the screen takes the position 10' shown in broken lines in FIG. 1. The image that it produces is reflected by the upper portion 28 of the parabolic mirror 22. then by the lower part 30 of this mirror 22 and from there is focused at the same location 18.

The position of the spectator is detected by a means of shooting comprising a camera 32 as well as means for recognizing the body of the spectator, such as a part of his face, especially the eyes.

The relief effect comes from the fact that the image of the screen is focused at a point in the space and, thus, the viewer does not have the impression to observe a screen but to see a floating object in the air . In addition, the relief effect is magnified by the synchronization of images to the viewer 's movement.

In another embodiment, which is shown in Figures 2 and 3, there is provided a screen 36 and an optical device with two reflecting mirrors 38 and 40 and the entire screen and mirrors 38 and 40 is integral with a housing or chassis 42 associated with control means for rotating this frame about a horizontal axis and a vertical axis 46. The screen 36 and the mirrors 38 and 40 have a fixed position relative to the frame 42. Thus, as can be seen in FIG. 3, the housing 42 has a large front opening 48 in front of the mirror 40. And the virtual image is formed in front of this front opening 48.

The front part of the system comprises, in the upper part, a camera 50 for detecting the position of a part of the face, such as the eyes or the nose, for example, of the viewer. In addition, two cameras 52 and 54 are provided in the lower part for detecting the position of the spectator 's hands when they approach the opening 48, that is to say when they approach the location where is focused the virtual object.

Alternatively, the camera 50 is used to detect both the position of a part of the face and the position of the hands.

Of course, depending on the desired interaction between the virtual object and the viewer, the cameras and the associated processing means are arranged to detect other parts of the body. For example, in one variant, the cameras 52 and 54 (or the camera 50) are provided for detecting the feet of the viewer in the case of a game using a virtual balloon.

In one embodiment, the computer processing means associated with the device represented in FIGS. 2 and 3 are such that they comprise means for effecting a correction of the geometry of the scene when the parameters of the optical systems change, such as, for example, , the distance between the screen 36 and the mirror 38 or the focal length of the mirrors 38 and 40.

Such corrections of the geometry of the images are conventional. These software means are for example included in a graphic processing unit or GPU (graphie processor unit). It is also possible to use a software means of processing of images to limit the movement of the screen assembly 36 and mirrors 38 and 40. In this case, the computer processing means comprise, for example in the graphics processing unit, a software means for performing a correction of the geometry of the object or scene examined in relation to the position of the viewer relative to the frame or casing 42.

This software means allows the geometric correction of the images so that they do not appear deformed to the viewer when it moves away from the line of sight for the case 42. The correction depends only on certain characteristics of the optical system, in particular the characteristics of the mirrors 40 and 38.

This software means is of the same type as that used to correct images projected on curved screens, for example parabolic or spherical screens.

In addition or alternatively, the computer processing means modify the position of the object or the scene when the viewer moves so that the object or the scene remains in the central position.

The correction, performed by the computer processing means, can be used to maintain the fixed housing 42 when the movements of the viewer are small. For displacements of an amplitude greater than a predetermined value, the movements of the spectator cause the housing 42 to move as described above.

These computer processing means performing the geometry correction or the position correction also make it possible to increase the relief effect because the object or scene represented moves relative to the frame. There is also the possibility of increasing the impression of the object 's immobility in space when this object is close to the viewer, whereas distant scenes or objects may appear to move more than nearby objects. (parallax effect due to movement). These computer processing means can also be used to reduce the reaction time of the system to the movements of the viewer. Indeed, even if the housing 42 moves for slight movements of the viewer, this displacement of the housing 42 is not always immediate because of the inertia of this housing. To oppose this delay, the computer processing means perform a geometry correction or position that takes into account, at each moment, the actual relative position of the viewer relative to the optical system.

FIG. 4 is a diagram of an assembly for videoconferencing providing relief images which comprises, for each interlocutor, a system 60, 62 of the type shown in FIG. 1 or in FIGS. 2 and 3. or systems 60, 62 comprises the various components already described in relation with FIGS. 1, 2 and 3, that is to say in particular a camera (not shown in FIG. 4) for detecting the position of the face, in particular the eyes, the viewer. In this system, the images provided are in particular the faces of the interlocutors. In other words, the image supplied to the viewer 64 of the system 60 is the image of the face of the viewer 66 of the system 62.

So that the angle under which the viewer 66 is viewed by the viewer 64 corresponds to the desired angle, which is determined by the position of the eyes of this viewer 64, the camera 62 is associated with a camera 70 and means to move the latter along a trajectory 72, so that this camera takes the image of the viewer 66 according to the angle desired by the viewer 64.

Similarly, the camera 60 is associated with a camera 74 traveling on a trajectory 76, this camera 74 providing the viewer 66 with a view of the interlocutor 64 according to the angle desired by the viewer 66, that is to say say according to the position of the eyes of the interlocutor 66 in the example. In a variant, each apparatus 60, 62 is associated with two cameras (not shown) providing two different viewing angles of the viewer and these two viewing angles are transmitted to the other speaker's camera. In this case, the apparatus comprises processing means for providing, from the two views received, a view corresponding to the angle desired by the viewer at the other end.

We will now describe in connection with Figure 5, an embodiment for presenting an extended scene in depth or several objects at different distances from the viewer.

In this embodiment, several screens are provided at a distance from each other, on each of which is formed or projected an image. There is thus provided a first screen 100 intended, for example, to represent a landscape or a distant object. This screen 100 is, for example, liquid crystal TFT technology. At least one other screen HO ₁ is disposed above the screen 100, that is to say between the screen 100 and the mirror 3B ₁ . This screen HO ₁ is intended to represent an object remote from the scene or object represented by the screen 100.

This screen HO ₁ is transparent so as not to completely obscure the image projected by the screen 100 to the mirror 3S ₁ . To obtain this result, use is made, for example, of an HO ₁ screen of the OLED type, that is to say a screen of electroluminescent diodes of the organic type.

It is of course possible to provide other transparent screens above the screen HO ₁ to increase the relief effect obtained by the system.

Because the screens 100 and HO ₁ not located at the same distance from the mirror 38 would be ₁₇ the images produced without treatment views so deformed by the viewer. That is why, in the computer processing means generating the images, means for correcting the image geometry are provided, so that the object or scene coming from the screen 100 and coming from the screen HO ₁ appear without distortion or focus defect for the viewer.

The means for correcting the geometry is also associated with control means making it possible to supply each screen with the image that belongs to it. The distribution of the images on the screens is carried out, in one embodiment, during the creation of the scene. For example, a scene is created in two dimensions and each object is assigned a Z coordinate value (distance to the viewer or depth) that is different from one object to another, the value of Z determining the screen on which we must form each object. In other words, either the assignment of the screen is predetermined, or the assignment of each object to a screen depends on the range of coordinates Z in which this object is located. In one embodiment, the images formed on each of the screens appear continuously.

Alternatively, the images on each of the screens alternately appear at a rate sufficient for the viewer to feel, by the effect of retinal persistence, to see both images simultaneously. Under these conditions, the image coming from the screen 100 is not obscured by the image on the screen HO ₁ since, when the screen 100 is active, the screen HO ₁ is inactive and therefore transparent. In addition, the visual effect obtained with this realization is different from the visual effect obtained when the screens continuously produce the images. Thus one will choose the mode of continuous or alternating operation according to the desired visual effect.

The invention is of course not limited to the specifically described embodiments. It encompasses the variants. In particular, for the shooting means, it is possible to use different devices of a camera. Thus, in the case where the apparatus is of the holographic type, a laser system is provided for shooting.

Claims

1. Three-dimensional image rendering system comprising:

a first screen (100) and at least one second screen (HO ₁ ) receiving and reproducing images, these two screens being at a distance from one another,

an optical device (20, 22; 38, 40) for producing an image (18) of the screens in the space, and

synchronization means (32, 50, 52, 54, 70, 74) of the nature of the images produced at the position in the spectator space (12) with respect to the system, so that, on the one hand, the The image remains in the spectator 's field of vision and, on the other hand, the viewing angle of the image obtained on the screens corresponds to the viewer' s position, especially that of his / her face.

2. System according to claim 1 wherein the second screen is closer to the optical system than the first screen and is substantially parallel to the first screen, and parts of the second screen that do not produce images are transparent.

3. System according to claim 2 wherein the second screen is organic-type light emitting diodes.

4. System according to one of claims 1 to 3 comprising control means for the images to appear simultaneously on both screens.

5. System according to claim 1, comprising control means for the images to appear at different times on the two screens, the frequency of appearance being sufficiently high for the spectator, by the retinal persistence, to simultaneously see the images. two screens.

6. System according to one of claims 1 to 5 comprising computer processing means which comprise image generating means, for example memory, and means for assigning each part of an image to a screen according to the relative distance of that part to the viewer.

7. System according to one of the preceding claims, comprising computer processing means for effecting a correction of the geometry of the images as a function of the position in the spectator's space with respect to the system and / or according to the position of the viewer. screen relative to the optical device, these computer processing means performing a geometric correction for correcting the deformations caused by the different distances of the screens.