EP0680683A1

EP0680683A1 - Method and apparatus for use in producing three-dimensional imagery

Info

Publication number: EP0680683A1
Application number: EP94904921A
Authority: EP
Inventors: Donald Lewis Maunsell Martin
Original assignee: Trutan Pty Ltd
Current assignee: Trutan Pty Ltd
Priority date: 1993-01-22
Filing date: 1994-01-24
Publication date: 1995-11-08
Also published as: PL309947A1; BG99808A; HU9502245D0; HUT73088A; EP0680683A4; JPH08508369A; FI953481A0; WO1994017638A1; NO952876D0; BR9406312A; CZ188295A3; CN1118210A; FI953481A; NO952876L; CA2154259A1; KR960700611A

Abstract

A method and apparatus for producing three-dimensional imagery, inclusive of displaying on the screen, imagery including two or more spaced-apart angles of view about a common centre and being segmented and separated. The segmented and separated imagery is viewed through grid means of a size and shape corresponding substantially to dimensions of the segments of imagery. The grid is placed at a distance from the screen such that segments of imagery acquired left of a common image centre are seen through the grid substantially by the left eye of a viewer, while segments of imagery acquired right of a common image centre are seen through the grid substantially by the right eye of a viewer. The relationship of left and right segments of imagery relative to said grid is maintained by oscillation of said grid relative to said segments of imagery appearing on said screen.

Description

METHOD AND APPARATUS FOR USE IN PRODUCING THREE-DIMENSIONAL

IMAGERY

FIELD OF INVENTION

The present invention relates to a method and apparatus for use in producing three-dimensional imagery.

PRIOR ART

Up until this time, three-dimensicnal imagery has essentiall been produced with means that present different aspects of objects to each eye and usually with filtered, polarised or oscillating imagery that can be observed through filtered, polarised and/or oscillating viewers or spectacles. Lenticular arrays, static or dynamic double vision strips an viewing slots arrangements also attempt a similar effect without the use of such viewers or spectacles.

The term "three-dimensional imagery" is an expression that h been in common use for many years. Since its first use, the meaning of the term has been extended to encompass a wide variety of depth enhancement imagery, as well as imagery tha actually contains three visual dimensions. Within the range of relevant methodologies, equipment and effects, there can be said to be two broad and general categories.

One of these categories involves imagery containing a single angle of view of an object. The other applies to images that simultaneously comprise two or more angles of view of essentially the same object.

Methods and apparatus that enable the presentation of two or more different angles of view of substantially the same objects simultaneously, are also referred to as three-

SUBSTΪTUTE SHEET Rule26 dimensional. Usually, these arrangements present two spaced angles of view, acquired at distances of 2 1/4 - 2 1/2 inches apart with a common centre, by the use of methods and means that isolate left views to left eyes and right views to right eyes. Left and right view separated systems include spectacles, viewers and visors ranging in sophistication from (as indicated hereinbefore) simple filtered or polarised spectacles to liquid crystal visors synchronised to screen signals. Other techniques for keeping left and right angles of view visible only to the corresponding eye include view differentiating lenses - particularly lenticular arrays and separated static right and left image strip arrangements.

In addition, holograms produce three-dimensional imagery containing multiple angles of view. Further, there are many combinations of these various systems.

However, despite the abundance of methods and techniques for enhancing image depth and producing imagery containing three visual dimensions, all have very limited application and have had limited commercial and practical success. In particular, none of the known systems are suitable for adaptation to most imaging systems in general use, such as for example cinemas, video and computer display units, television screens and the wide variety of monitors used in every day life for functions ranging from medical investigations, to entertainment, to military surveillance.

It is an object of at least one aspect of the present invention to provide a method and means for displaying three- dimensional imagery which goes some way towards overcoming or minimising problems and shortcomings associated with methods and means known up until this time. Other objects of this invention will become apparent from the following description.

DISCLOSURE OF THE INVENTION

According to one aspect of this invention there is provided a method of producing three-dimensional imagery including displaying on a screen, imagery including two or more spaced- apart angles of view about a common centre and being segmented and separated; said separated segments of imagery being viewed through grid means of a size and shape corresponding substantially to the dimensions of said segments of imagery, wherein said grid is placed at a distance from said screen, such that segments of imagery acquired left of a common image centre are seen through said grid substantially by the left eye of a viewer, while segments of imagery acquired right of the common image centre are seen through the grid substantially by the right eye of a viewer; the arrangement being such that the relationship of left and right segments of imagery relative to said grid is maintained by oscillation of said grid relative to said segments of imagery appearing on said screen, in substantial synchronisation, and at a speed which produces coherent, complete, three-dimensional imagery to the eyes of a viewer.

According to a further aspect of this invention there is provided a method of producing three-dimensional imagery including displaying on a screen surface, imagery containing two or more spaced-apart angles of view about a common centre, and which angles of view have been segmented and separated; said segmented and separated angles of view being viewed through sections of a grid, of a size and shape corresponding substantially to the dimensions of said segments of imagery; said grid being placed at a distance from said screen where segments of imagery acquired left of a common image centre are seen through sections of said grid substantially by the left eye of a viewer, while segments of imagery acquired right of the common image centre are seen through grid sections substantially by the right eye of a viewer; the relationship of left and right segments of imagery, relative to said grid sections being maintained when said imagery is displayed on said screen, by oscillation of said grid sections in synchronisation with the display of said segments of imagery at a speed which produces the appearance of a coherent, complete, three-dimensional imagery.

According to a further aspect of this invention there is provided a method of producing three-dimensional imagery including displaying on a screen surface, imagery containing two or more spaced-apart angles of view about a common centre, and which angles of view have been segmented and separated; said separated and segmented angles of view being viewed through sections of a grid, of a size and shape corresponding substantially to the dimensions of said segments of imagery; said grid being placed at a distance from said screen where segments of imagery acquired left of a common image centre are seen through sections of said grid substantially by the left eye of a viewer, while segments of imagery acquired right of the common image centre are seen through grid sections substantially by the right eye of a viewer; the relationship of left and right segments of imagery, relative to said grid sections being maintained when said imagery is displayed on said screen, by oscillation of said grid sections in synchronisation with the display of said segments of imagery at a speed which produces the appearance of a coherent, complete, three-dimensional imagery; and wherein said grid sections become substantially invisible to the eye as a transparent window between said eyes of a viewer and said screen.

According to a further aspect of this invention there is provided an arrangement for producing three-dimensional imagery, including means for displaying on a screen surface imagery containing two or more spaced apart adjacent angles of view about a common centre and which angles of view have been segmented and separated; a grid means being provided in front of said screen such that said separated and segmented angles of view of said imagery are viewed through sections of said grid, of a size and shape corresponding substantially to dimensions of said segments of imagery; said grid means being spaced apart from said screen by a distance, such that segments of imagery acquired left of a common image centre are seen through sections of said grid substantially by the left eye of a viewer, while segments of imagery acquired right of the common image centre are seen through grid sections substantially by the right eye of a viewer; the relationship of left and right segments of imagery, relative to said grid sections being maintained when said imagery is displayed of said screen by oscillation of said grid means and grid sections, in synchronisation with the display of said segments of imagery on said screen at a speed which produces the appearance of coherent, complete, three- dimensional imagery.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The invention will be described by way of example only and with reference to the accompanying drawings wherein:

Fig. 1 is a diagrammatic plan view of one form of the present invention, and Fig. 2 is a diagrammatic plan view of a further form of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF THE PRESENT INVENTION AND METHODS OF CARRYING OUT SAME

As described above, this invention provides a method and an apparatus for producing imagery that can be displayed on a screen and viewed through an oscillating grid so that the imagery appears entirely in three physical dimensions.

The invention combines two discoveries. Each of the discoveries are extensions of previous discoveries related to earlier inventions and both of the new discoveries permit improvements on these earlier inventions.

The two improvements, combined together, produce three- dimensional imagery that is practical and commercially viable for many purposes for which it is desired.

The first improvement involves the presentation of three- dimensional imagery on a screen.

Until now it has been believed that it is not possible to present two, or more, angles of view acquired about a common centre of the same object on a screen, in which all elements of each image are fully in alignment, so that, together, the multiple adjacent angles of view appear as a single coherent three-dimensional image, with the exception of the extreme outer edges of the images.

It seems that there are two reasons for this believe. Firstly, because of a general presumption that, for people, three-dimensional imagery is primarily a function of the human eye span. Secondly, because describing human vision in terms of solid geometry, demonstrates, necessarily, that either eye must see any identical point on a screen at a different position to the other eye.

In the first case there is no set standard at which the varying distances between the pupils of the human eyes are established as optimised, averaged, or otherwise laid down as generally appropriate for everyone to view three-dimensional imagery.

Despite this, it appears accepted widely that for the purposes of producing three-dimensional imagery, two-and-a- quarter to two-and-a-half inches of separation between image centres is required.

Images acquired at this order of separation about a common centre cannot be presented on a screen so that they appear aligned completely in three dimensions to the unaided eyes.

Further, because solid geometric depiction of human observations show that each eye must see the same point at a different position on a screen, it has been held to follow, therefore, that, except for the centre, no points of two, or more, adjacent images acquired from different angles around a common centre can be seen by both unaided eyes in the same position on a screen and, therefore, aligned and in three dimensions.

For both these reasons, it seems to have been accepted generally for many years that two or more images of essentially the same object acquired adjacently, in a manner simulating human eye views, cannot be aligned on a screen and, consequently, can be seen in three dimensions only if the images are seen by the respective eyes quite separated so that neither eye can compare any part of the two views on a screen and thus observe two different images.

Human perception of three-dimensional imagery has been widely understood through this century, as the separate and separated viewing of two different angles of view of objects, viewed from positions spaced apart at a distance equivalent to the width of the pupils of the eyes, or about two-and-a- half inches.

The production of three-dimensional imagery has therefore followed this appreciation by presenting it mainly through view differentiating spectacles.

This presentation of three-dimensional imagery with the requirement to wear appropriate viewers appears to be the main impediment to more widespread use of such imagery, due to public resistance to using this type of opticals.

Other attempts, such as applying lenticular arrays to screens have different drawbacks, such as limited viewing area because of the requirement to keep the eyes at the lens focal centre.

Still more different solutions, like holographic approaches, are limited by cost considerations.

It is a primary point of this invention that the basic belief that two or more adjacent angles of view cannot be aligned in three dimensions on a screen for observation by the unaided eyes is fundamentally flawed, and this discovery opens the way to improvements in technology that overcome the impediment of having to wear viewers to see three-dimensional imagery, or use techniques with equal or greater undesirabilities. In 1923 Demetre Daponte demonstrated that two adjacent angles of view, acquired with centres approximately two-and-a-half inches apart, could be aligned partially in three dimensions on a screen by alternatively dissolving each view in and out against the other.

Daponte' s invention demonstrating this discovery was called "The Pulseometor". It comprised two discs of transparency graduated from complete to zero, rotating in opposite directions so that each angle of view projected through the discs fades and brightens in illumination in opposition to the other view.

Daponte' s discovery and invention demonstrated only partial alignment of two images in three dimensions, and the proportion of the images so aligned was small, comprising less than one quarter of the horizontal length of the image.

It is one of the discoveries of this invention that images comprising two, or more adjacent angles of view, can be aligned completely in three dimensions on a screen, providing that the angle between the views and the distances between the foreground and background of the object are sufficiently small.

In practice, this angle of separation and the distance between the background and the foreground of the object is dependent upon the distance of the object centre; the total depth of field; type of lenses used; centres of focus; and vertical as well as horizontal alignment of the images.

Regardless of all these variables, the angle is always very small for objects closer than 40 feet and the differences between both images difficult to discern; despite the physical separation of the image centres, high quality resolution equipment is essential.

As a guide it has been found that this angle of view is less than one quarter of a degree for objects at less than forty feet.

The importance of this discovery is that in combination with another discovery and another improvement of another invention this very small angle of displacement can be increased in a flexible way that permits application to most conventional imagery equipment.

In essence this is accomplished by applying a system of variable separation to the two different images and altering the degree of separation as required.

Like other aspects of three-dimensional imagery, it has been known for more than a century that three-dimensional imagery can be produced by segmenting left and right angles of view of an object and arranging the strips on a flat surface separated by slats, or similar dividers, so that observers can position their eyes to have the left eyes seeing left image strips while the slats block the left eye views of the right image strips and the right eyes see the right image strips, while the slats block the right eye views of the left image strips.

This well known arrangement produces a three-dimensional combination but is always limited by the degradation to the overall effect caused by the view differentiating slats.

Another approach was demonstrated by Francois Savoye in the early 1950s, when he produced and applied for a patent for his "Cyclostereoscope". The cyclostereoscope comprises a circular grid rotating about a screen on to which left and right adjacent angles of view were projected through the grid.

The concept, described by Savoye, envisaged transposing the approach of view separating visors, worn around the eyes of viewers, to a similarly functioning arrangement operating around the screen.

Savoye envisaged the grid, alternatively blocking each eye view of a different combination of strips of angles of view and the whole grid rotating to sequentially reveal all segments at a speed that would permit memory and vision to together perceive the strips combined as two whole images in three dimensions.

This Savoye achieved partially and prescribed zoned seating arrangements to confine viewers to areas where three- dimensional views were optimised and views of two overlapping images minimised.

An improved grid viewing system is an exclusive feature of this invention which overcomes the zonal problems of the Savoye idea as well a dispensing with the limitations of a rotating, circular grid.

It is a second discovery of this invention that images containing two, or more, adjacent angles of view acquired around the common centre of essentially the same object can be aligned in three complete, and coherent, dimensions, except the extreme outer edges, in increasing divergence of angle, with increasing separation between the different images, and the corresponding viewing eyes. In practice, it is necessary to segment and separate the images sequentially so that an equal number of equally sized and equally spaced images are presented on a screen and then viewed through a vertical grid so that left eye views of image segments left of the common object centre are separated from right eye views of image segments right of the common centre in increasing degrees of exclusion as the angles of divergence between the images increase.

As a guide, the system applied to two or adjacent angles of views acquired around a common centre of an object, where the centre of each different view are horizontally separated from approximately a quarter of an inch to five inches for any two adjacent angles of view.

For extreme close-up views or views beyond visual infinity, these positions will be lesser or greater.

To maintain this relationship in a way that overcomes the limitation of a rotating, circular grid, or the inertial forces of an oscillating mechanical grid, the grid system can be supplied by grids formed with a liquid crystal display synchronised with the segmentation of the imagery.

To produce a complete three-dimensional imagery and remove the appearance of grid lines degrading the imagery, the segmented and separated imagery, enhanced in separation by the grids, can be oscillated together in synchronisation so that their functions are maintained at a speed, for example in excess of fifty hertz, where the segments merge into a complete, coherent, three dimensional image and the grid lines are oscillating too fast to be seen.

This combination produces zone-free three-dimensional imagery of any angle capable of human perception by widening or narrowing the grid lines, without inertial limitations, or incompatibility with almost all conventional equipment.

Up until this time, three dimensional imagery has been created and viewed as what could be termed, "the two separate views" type. This can be done through spectacles, known means and apparatus and the like. Essentially however three- dimensional imagery of the "two separate views" type involving separate right- and left-hand views and the sequential blocking off of these views, is not capable of producing visual realism as people are used to experiencing it. In other words, as the eyes normally communicate the views to the brain. Such three-dimensional imagery tends to be identifiable as imagery and thus unnatural. Further, there are other drawbacks with such known forms of three- dimensional imagery, including for example limitations on the angles from which imagery can be seen, incompatibility with conventional equipment, difficulties with transmission and broadcasting, substandard qualities, eye strain and lack of commercial viability and reality, as well as problems with many people who have abnormal vision.

As a background of the present invention, and for the purposes of the description and definition herein, it is generally believed that it can be said that the eye should in many cases be conceived as something of a dynamic sensor. The eyes of a human being generally see both horizontal and vertical planes substantially simultaneously, together with constantly varying fields of depths and focal points. This essential dynamic sensing, coupled with the memory, maintains impressions of infinitely variable views of everything seen by the eyes. It is generally believed that the mind is not given one clear left or one clear right view, but is continually given a range of different partial and adjacent images. These varying partial and adjacent images are combined by the mind or brain of a human being into a single coherent whole which has depth of image and which clearly appears in three dimensions.

It is also generally believed that the eyes of a human are rapidly and continuously scanning. As indicated, they do not, it is believed, continuously focus on one point, giving one right view and one left view. The eyes have a continuously changing field of view and both eyes are continuously shifting over varying points, one crossing over the other's field of view. Further, humans are often continuously moving their heads, and eye balls are often moving within their sockets. Thus, far from the mind or brain of a human having transmitted to it, two dissimilar changing views or photographs (one right and one left) , what the mind or brain is receiving is continuous partial and adjacent, segmented and separated views of imagery.

Up until this time, it is believed that the opticals using the principle of producing two distinct views to simulate the perceptions of three dimensions are limited by inherent restrictions. Such restrictions confine such systems and means to representations of three dimensions in single horizontal planes with fixed field depth and fixed focal length. It will be appreciated from the above that these are not realistic, and are perceived as such. In practice, such known systems are precluded from reproducing realistic three- dimensional imagery.

A fundamental feature of the present invention is that it produces a commercially viable method for producing three- dimensional imagery, by removing the necessity for wearing view differentiating spectacles and for using other intermediate opticals between the imagery and the observer. The present invention, in its preferred forms, accomplishes the production of wide angle three-dimensional imagery, with comparatively little alteration and addition to existing technology, by containing about a common centre within each image, multiple, adjacent angles of view that are displayed partially and progressively across the screen, in apparent full alignment, as separated image segments, or as a combination of separated image segments, changing to cumulatively reveal the continuously varying spatial displacements between the segments of images on the screen and, at sufficient speed, as constant visual displacements between the subject elements of a steady, single, coherent and complete three-dimensional image.

The present invention also provides that the angles between the multiple views about a common centre of each image are such that the rapidly changing segments of images containing the angles produce an apparent constant visual displacement between the subject elements of the image, at the same time that the subject elements within the image appear to remain in alignment, so as to prevent or minimise the appearance of more than one image, or multiple imagery within any part of the image.

The term "production" means acquisition, generation or construction for immediate display upon a screen, or immediate transmission for display, or immediate broadcasting for display. In addition, "production" can mean acquisition, generation, or construction for storage and later display, transmission, broadcasting or projection.

Equipment used for acquisition includes cameras, cine cameras, video cameras, holographic camera arrangements, or any device capable of acquiring imaging containing multiple, adjacent angles of view about a common centre in a manner such that the acquired imagery can be presented, separated and segmented for display so as to appear three-dimensional on a screen.

Segmentation of the multiple adjacent angles of view about a common centre can take place as the imagery is acquired, within a camera-like system, or anywhere before display such as during, or as part of, film processing; storage input or retrieval; or editing; for the production of slides; film prints or video tapes for release; in transmission or broadcasting; or on reception.

In addition, appropriate segmented imagery can be manufactured in the generation of imagery, such as computer imagery or symbology, or in the production of caricatures.

By "image" a single whole image is meant such as contained by a slide; one frame of a film; one image on a video tape; an x-ray; or any other clearly definable view capable of being recorded, stored, transmitted, broadcast, displayed, projected, presented or generated to duplicate actual objects, symbols; or represent objects or symbols such as computer generated imagery or caricatures. In addition, by image or imagery, series of single images presenting the same view or continuation of a view are included.

By display is meant projected, presented, illuminated or generated so as to be visible to the eye.

By screen is meant any surface upon which the imagery can be displayed, presented, projected or generated so that it becomes visible; or any volume in which imagery can be made to appear. By alignment is meant that each imagery is registered apparently exactly upon any other in size, shape, vertical and horizontal position, so that multiple images appear as differing only in the appearance of depth or dimensionality and never as more than one image, or more than one part of any image, necessarily the same shape, that is revealed progressively across the screen.

In practice the size of the segments will vary according to the medium used for acquisition or viewing.

The present invention provides a method and arrangement, whereby imagery is recorded in such a manner that realistic and commercially viable three-dimensional imagery can be subsequently, or substantially simultaneously, be shown on a screen surface. The imagery can be recorded on any appropriate media, such as film, tape, slides, holograms and the like. In one form of the invention the imagery is recorded on media so that it can be subsequently shown such as in the cinema by way of slides or photographs, on a television, on a video set and the like. In further forms of the invention, means for recording the imagery, such as a camera or cameras, are in the form of a camera or cameras which are themselves, or in conjunction with appropriate transmission means, able to immediately transmit the recorded imagery to means such as television sets and the like which will receive and show the recorded imagery on a screen surface. For example, such as television cameras used in outside broadcast units for television news, sporting events and the like. These are by way of example only. Thus, it should be appreciated that the present invention relates to a method and arrangement for the recording of imagery for subsequent or substantially simultaneous viewing on a screen surface. The present invention does not relate to a method and arrangement for enabling previously recorded imagerv to be viewed on a screen so as to appear in three dimensions.

The method and arrangement of the present invention require the provision of a lens or lens system, that allows for the recording or acquisition of two or more substantially adjacent, similarly sized angles of view of imagery or objects that are to be recorded. Generally, it is better to acquire or record a plurality of smaller adjacent angle views rather than a smaller number of larger angle views. It should however be appreciated that in the present invention it is essential that two or more differing angles of view be recorded.

In addition, it is a further feature of the present invention that the imagery be recorded for subsequent or simultaneous viewing so that at all times only partial and adjacent sections of each angle of view are acquired or recorded. As will be appreciated, this means that when the imagery is displayed, none of the multiple angles of view appear to the eyes completely at any one instant, but rather are revealed only as a sequence of segments, at a speed to the eye which merges the segments together at differing angles, so that when viewed, the recorded imagery is perceived by the eyes to have depth in imagery and to be in three dimensions; that is, in accordance with the normal working or operation of the eyes of a human.

Tn one preferred form of the present invention the partial and adjacent angles of view are recorded in a non-sequential manner, by using the apparatus and method of the present invention. The recording of such non-sequential adjacent and partial angles of view, in accordance with the present invention, allows for such non-sequential adjacent and partial angles of view to be subsequently shown by means of the present invention so as to be viewed with depth of imagery and in substantially three dimensions, by the eyes of a viewer.

The present invention provides that means be provided in association with the lens or camera, or in association with the recording of the multiple angle views, so that the imagery is recorded in a partial, adjacent and spaced apart manner. To that end, the invention requires the provision of a grid, grid system, separator, angle of view interrupter, light or signal blocking mechanism, switch or process means, as a component or feature, essential to the recording of the imagery, so that the imagery as recorded, is recorded partially and from two or more spaced apart, adjacent angles of view.

The present invention is described with reference to the imagery being recorded from two spaced angles of view - one left angle and the other a right angle. This is however by way of example only and it should be appreciated that the imagery can be recorded from two or more angles of view.

The means for use in recording partial and adjacent multiple angles of view can be separate from the recording means such as the camera or can be incorporated into the camera. Various forms of the invention will be described hereinafter by way of example only and with reference to the accompanying drawings, but it should be appreciated that these are by way of example only. For example, a camera can have included into it appropriate means for causing the imagery to be partial and adjacent, such a means being in the form of for example an interrupter, such as a grid system which can be built into the camera but arranged so as to avoid interference with the shutter or scanning function. Further, any such arrangement should be timed to obviate as far as possible the production of lines, strobing, moire or other optical noise, distortion or image degradation.

It is however envisaged that in one form a camera can be an electronic camera which can be programmed so that it can record partial and adjacent angles of view of the article or articles being recorded. Such a camera can have a plurality of spaced lenses, or alternatively a plurality of such cameras can be utilised, the recorded imagery thereafter being mixed and processed.

In forms of the invention where an interrupter or grid arrangement might be provided within the camera, such an arrangement can be provided before, within or behind the lens or in any position wherein it positively interrupts the acquisition or recording of imagery, through the lens, so that only partial and adjacent images are recorded on the media or recorded by the camera.

It is envisaged that when such an arrangement is incorporated into a camera, the grid or interrupter arrangement will be preferably placed behind a lens, adjacent and as close as possible to the film plane and will be synchronised with the camera shutter or might replace the shutter or be incorporated into the film gate.

In various forms of the invention, where a plurality of angles of view have been acquired and recorded by films or electronically, the recorded multiple angles of view can then be subsequently altered so as to include partial and adjacent angles of view, such as by known mechanical, electro-optical, electrical, or other means, such as for example segmentation mixes and the like. It is further envisaged that media, such as film or tapes, with a programmed grid or pattern applied thereto, or gaps therein, could be used in a camera to simplify the recording componentry. In yet a further form of the invention it is envisaged that display units presenting image interrupting patterns could be used to mix multiple angle views. For example, a liquid crystal display could be used that presented image segmenting lines or gaps traversing the display of the required speed, to form a dynamic optical grid.

The invention will now be further described with reference to preferred embodiments thereof, and with reference to the accompanying drawings (as referred to hereinbefore) .

In a preferred form of the invention the imagery is shown on a screen, as a result of being computer-generated or produced on the screen, or by being displayed on a screen by way of protection. In the accompanying drawings, by way of example only, the imagery is shown as being viewed through the grid means - (to be described further hereinafter) .

The screen 1 is shown as having a screen surface 2 and grid means is provided substantially in front of and spaced apart from said screen surface 2, the grid means 3 preferably being in the form of a liquid crystal display screen, which on operation generates a plurality of oscillating grid sections 4, through which the imagery can be viewed on the screen. Other forms of grids can be used if desired. For example, physical grids extending across the front of a screen, provided with a plurality of slots or openings 4 thereof of varying depth. It is however preferred that the grid means have a plurality of grid sections or openings therein and is preferred that the grid means 3 be in the form of a liquid crystal display screen or other appropriate electrical or chemical optical arrangement which provides physical separation of imagery.

The liquid crystal display screen is preferably arranged so that the grid 3 oscillates to meet the requirements of the present invention. In other forms of the invention. Grid means can move or oscillate by means of additional mechanisms or electric power means.

By way of example only and referring to Fig. 1 of the accompanying drawings, the grid 3 is shown as being separated forwardly from the screen surface 2 and one form of the invention is shown (diagrammatically) as being embodied into a housing or cover 9 in front of the screen 1, be it a screen of a television set, a cinema screen or the like.

In a further form of the invention as shown by way of example only with reference to Fig. 2 of the drawings, a plurality of spaced apart grid means 3 can be provided to form channel sections or slots 4 therebetween so that on oscillation or movement thereof, imagery on the screen surface 2 will be seen therethrough in three dimensions.

As with other forms of the invention, the screen 1 and spaced-apart grid means 3 can be located or housed in a housing 9 so as to be substantially integral. Alternatively, they can be separate one from the other.

It will be appreciated that at least the grid means 3 can be for example in the form of crystalline, liquid crystal or similarly functioning electro-optical materials.

For use, in forming an appropriate grid or surface, the materials may for example be inorganic compounds, such as gilenium arsenide; lithium niobate; potassium dihydrogen phosphate; and barium borate; as well as organic compounds such as methyl nitroaniline and nitroaminostilbene; also materials from electron donors, such aε amino, methoxy, and hydroxy groups; and electron acceptor groups, such as nitro, cyanide, esther and nitroso groups; polymers; polyenes; and polydiacetglenes or any materials with electro-optical properties; light frequency changing properties; non- centrosymmetric molecular structure; or crystalline structures where anions have been completely replaced by electrons, such as in complex compounds, such as alkalide, potassium hexamethyl hyxacyclen sodium. The electro-optical material may be arranged in single pieces such as blocks, slabs or chips, or in a number of pieces, in large or small pieces of any shape, in films, in thin films, in solutions, in suspensions, sandwiched between other materials, such as glass, as mixtures with other electro-optical compounds, or as mixtures with other materials that are non-electro-optical compounds.

Where for example the electro-optical materials of the grid are arranged in lines, rods, strips, slats, panels or filaments, these can be positioned in rows, in partial rows, staggered rows, in parallel, in parallel rows, in horizontal or vertical rows (or both) or in intersecting rows. Further, of differing lengths and sizes and at different positions within the display.

As indicated, these are by way of example only and grids such as grids formed of any appropriate material with slots therein, adapted to oscillate in an appropriate manner, can be used to meet the requirements of the present invention.

As will be appreciated, in operation, the present invention allows for the display of three-dimensional imagery and the viewing of three-dimensional imagery (be it generated, produced or projected) such as in the manner described and claimed in our international patent application No PCT/AU92/00199. Thus, the imagery projected onto the screen or generated onto a screen or shown on a screen otherwise, involves displaying imagery on a screen which imagery includes two or more spaced apart adjacent angles of view about a common centre which are displayed and in a segmented and separated manner, substantially sequentially or alternately on a screen. The separated segments are viewed through sections of a grid, such as described with reference to Figures 1 and 2 of the accompanying drawings, which have sections or openings of a size and shape corresponding substantially to the dimensions of the segments of imagery displayed on the screen. The grid means is placed at a distance from the screen, such that the segments of imagery acquired left of a common image centre are seen through grid sections only by substantially the left eye of a viewer, while image sections acquired right of a common image centre are seen through grid sections substantially through the right eye of a viewer.

The relationship between the left and right segments of imagery, relative to the grid and sections thereof is substantially maintained when the grid sections oscillate, to enable the imagery to be viewed through the oscillating grid, the oscillation being at a speed and in synchronisation with the display of the segments of imagery, such that the imagery appears to the eyes of a viewer (through said grid means) to be coherent, complete and in three dimensions. It has been found that this avoids flickering, whole or partial appearance of any individual angles of view and it has also been found that the grid sections, on oscillating, become substantially invisible as a substantially transparent window between the eyes of a viewer and the screen. It should be appreciated that modifications and improvements to the invention may be made without departing from the scope thereof as defined by the appended claims.

Claims

1. A method of producing three-dimensional imagery, including displaying on a screen, imagery including two or more spaced apart angles of view about a common centre and being segmented and separated; said separated segments of imagery being viewed through grid means of a size and a shape corresponding substantially to dimensions of said segments of imagery, wherein said grid is placed at a distance from said screen, such that segments of imagery acquired left of a common image centre are seen through said grid substantially by the left eye of a viewer, while segments of imagery acquired right of the common image centre are seen through the grid substantially by the right eye of a viewer; the arrangement being such that the relationship of left and right segments of imagery relative to said grid is maintained by oscillation of said grid relative to said segments of imagery appearing on said screen, in substantial synchronisation, and at a speed which produces coherent, complete, three-dimensional imagery to the eyes of a viewer.

2. A method of producing three-dimensional imagery including displaying on a screen surface, imagery containing two or more spaced apart angles of view about a common centre, and which angles of view have been segmented and separated; said segmented and separated angles of view being viewed through sections of a grid, of a size and shape corresponding substantially to the dimensions of said segments of imagery; said grid being placed at a distance from said screen where segments of said imagery acquired left of a common image centre are seen through sections of said grid substantially by the left eye of the viewer, while segments of imagery acquired right of the common image centre are seen through grid sections substantially by the right eye of the viewer; the relationship of left and right segments of imagery, relative to said grid sections, being maintained when said imagery is displayed on said screen, by oscillation of said grid sections in synchronisation with the display of said segments of imagery at a speed which produces the appearance of a coherent, complete, three-dimensional imagery.

3. A method of producing three-dimensional imagery including displaying on a screen surface, imagery containing two or more spaced apart angles of view about a common centre, and which angles of view have been segmented and separated; said segmented and separated angles of view being viewed through sections of a grid, of a size and shape corresponding substantially to the dimensions of said segments of imagery; said grid being placed at a distance from said screen where segments of imagery acquired left of a common image centre are seen through sections of said grid substantially by the left eye of the viewer, while segments of imagery acquired right of the common image centre are seen through grid sections substantially by the right eye of a viewer; the relationship of left and right segments of imagery, relative to said grid sections, being maintained when said imagery is displayed on said screen, by oscillation of said grid sections in synchronisation with the display of said segments of imagery at a speed which produces the appearance of a coherent, complete, three-dimensional imagery; and wherein said grid sections become substantially invisible to the eye as a transparent window between said eyes of a viewer and said screen.

4. A method of producing three-dimensional imagery as claimed in any one of the preceding claims, wherein said grid means is in the form of a screen including electro-optical materials.

5. A method of producing three-dimensional imagery as claimed in any one of the preceding claims, wherein the grid means is in the form of a liquid crystal screen.

6. An arrangement for producing three-dimensional imagery, including means for displaying on a screen surface, imagery containing two or more spaced apart adjacent angles of view about a common centre and which angles of view have been segmented and separated; a grid means being provided in front of said screen such that separated and segmented angles of view of said imagery are viewed through sections of said grid, of a size and shape corresponding substantially of dimensions of said segments of imagery; said grid means being spaced apart from said screen by a distance, such that segments of imagery acquired left of the common image centre are seen through sections of said grid substantially by the left eye of the viewer, while segments of imagery acquired right of the common image centre are seen through grid sections substantially by the right eye of the viewer; the relationship of left and right segments of imagery, relative to said grid sections, being maintained when said imagery is displayed on said screen; means being provided to cause said grid means to oscillate, such that said grid means and grid sections oscillate in substantial synchronisation with the display of said segments of imagery on said screen at a speed which produces the appearance of coherent, complete, three- dimensional imagery.

7. An arrangement as claimed in claim 6 wherein said grid means is in the form of a screen including electro-optical materials.

8. An arrangement as claimed in claim 6 or claim 7, wherein said grid is in the form of a liquid crystal screen.