GB2146877A - Producing stereoscopic visual displays - Google Patents

Abstract

A stereoscopic visual effect is obtained by viewing two non-overlapping displays 22, 23 on a single screen through a binocular eyepiece 26, 27 so that the left eye sees only the left screen 22 and the right eye only the right screen 23. The two displays may be produced from and changed by a programmed device 25 including for example a magnetic tape which changes at least part of the displays to give a moving stereoscopic effect. The apparatus may be used to play a video game using controls 33, 35. Other methods of generating a view such as television cameras can be used, the view being changeable by a viewer or in some cases a programmed electronic device. Hand-held and head-set devices are described. <IMAGE>

Description

SPECIFICATION Improvements in or Relating to Apparatus and Methods for Producing Visual Displays This invention relates to apparatus and methods for producing visual displays.

Two methods of creating a three-dimensional visual effect are known.

One method uses a camera with two lenses positioned side by side, i.e. simulating the positioning of a human's eyes. One lens is equipped with a red filter and the other lens with a green filter. The camera duplicates, in a very approximate way, on film the images seen by the eyes. When the film is projected onto a screen, the viewer covers his eyes respectively with red and green filters which separates the two images and creates a three-dimensional visual effect.

A second method also employs two lenses positioned side by side to imitate the function of eyes. Two slightly displaced images of the same view are created as is the case for human vision. When the separate images are viewed in such a way that each eye only sees its corresponding image, for example through a binocular viewer, a three-dimensional visual effect is created.

Video games of various kinds employ a cathode ray tube which displays visual images according to a programme which a player can affect by moving levers or buttons. Such games incorporate single image displays and the effect is therefore two dimensional.

According to another aspect of the invention a method of producing a visual display comprises producing two simultaneous visual displays, and viewing the displays to obtain a three-dimensional view, input means changing at least part of one display relative to the other to change the view, the displays being on a single screen.

The displays may be produced electronically.

The displays may be side by side and the viewer sees only one display through only one eye and only the other display through only the other eye.

The displays may be obtained through lenses respectively having green and red filters and are displayed on a single screen, and the viewer views the displays through respective green and red filters.

The input means may comprise a computer or the viewer.

One method comprises providing two visual displays on cathode-ray tube means, providing means enabling said displays to be viewed in such a manner that one eye sees only one display and the other eye sees only the other display, and the viewer producing relative movement between at least parts of the displays in a manner such that when viewed through the enabling means a moving three-dimensional effect is produced.

Also according to the invention apparatus in producing a visual display comprises means for providing two simultaneous visual displays, means for viewing the displays to obtain a three-dimensional view, and input means operable to cause relative movement between at least a part of the displays to change the view, the displays being on a single screen.

The input means may be adapted for operation by a viewer.

The display providing means may comprise a camera with two lenses respectively with red and green filters, a screen for said visual displays, and the viewing means comprises red and green filters respectively for a viewers' eyes.

The display providing means may comprise cathode-ray tube means having a display screen, and the viewing means comprises means enabling the viewer to see only one display through one eye and only the other display through the other eye, and including means for providing signals to said tube means to form the displays.

The signal providing means may comprise a magnetic tape, or two video cameras whose outputs are respectively connected to form the displays the outputs having a predetermined relation so as to simulate the displacement between a viewers' eyes.

There may be sound reproducing means operatively linked to the signal providing means.

The input means may comprise a computer.

Also according to the invention there is provided a method of flying an aircraft comprising obtaining by electromagnetic, for example infra-red, means displaced views of the view ahead, displaying said views respectively on two displays, and viewing said two displays to obtain a three-dimensional view, the displays being on a single screen.

The invention may be performed in various ways and some specific embodiments with possible modifications will now be described by way of example with reference to the accompanying diagrammatic drawings, in which: Figures 1 to 6 show the relationship between two visual displays to create a three-dimensional effect; Figure 7 is a perspective view of a video game apparatus; Figure 8 shows an initial display; Figure 9 shows a final display; Figure 10 illustrates objects at game start; Figure 11 is a side view, part in section, of a head set; Figure 12 is a plan view, part in horizontal section, of the head set; and Figure 13 is a perspective view of a three-dimensional viewer device for holding in the hand.

Described generally, in an exploratory test developed from the second of the three-dimensional methods described above, two cathode ray tubes were placed side by side and a viewing device was placed in front of them. It was arranged so that the left eye could only see the left-hand screen, and the right eye could only see the right-hand screen. In one case the signals from two television cameras, placed side-by-side with their lenses approximately three inches apart, were fed so that the signal from the left-hand camera was fed to the left-hand screen and the signal from the right-hand camera to the right-hand screen. The viewer when looking through the eyepiece saw a single three-dimensional picture.

In the present case a visual display is obtained using the same general arrangement, but the three-dimensional view is developed electronically using a computer programme and presented in a way which allows for slightly displaced images as described below, simulating the small difference of viewing position between the human eyes. When these displays are viewed through a binocular eyepiece, they appear as a single three-dimensional view. The programme may be designed so as to allow an operator to alter and thereby control the content of the picture, for example with the object of achieving some goal.

Programming devices as such are known in two-dimensional displayvideo games. However, in the present case, the changes are effected in one display and the other display is linked, by the programme, to the one display in a fixed relation simulating the displacement of the human eyes from each other. The result, when continuously viewed through a binocular eyepiece, presents a moving three-dimensional video display.

Some consideration relating to the changes in the displays on the two-dimensional screen in order to achieve a three-dimensional effect when viewed through a binocular eyepiece will now be given, the left eye of the viewer looking only at the left-hand display and the right eye of the viewer looking only at the right-hand display. Each eye sees a two-dimensional image or display although the viewer has a sense of depth by perspective or overlapping of objects in the image; when the two displays are viewed by binocular vision as above a three-dimensional or stereo-scopic visual effect is obtained. Thus an object may appear to be between the viewer and the screen, for example.

Position in Space Objects A, B, C displayed by corresponding images A, B, C, as in Figure 1 would appear when viewed through a binocular eyepiece with object B in front of object A and object C in front of object B.

An object appears further forward in relation to another object the greater the relative displacement of their respective images or displays.

Movement in Space In Figure 2 if displays a and b are viewed consecutively through a binocular eyepiece the object B in the three-dimensional view will appear to move towards the viewer.

The visual representations or displays on the screen of objects A have remained stationary and are of equal and unchanged size; the left-hand representation or display of object B has moved to the right whereas the right-hand representation object B has moved correspondingly to the left; the two representations of B have also increased in size by equal amounts. This makes B appear to move forwards.

The two images have also moved downwards which increases the apparent forward movement.

If the displays are viewed b first then a the apparent movement is reversed, and this applies also to Figures 3 to 6.

In Figure 3 if displays a and b are viewed consecutively through the binocular eyepiece the viewer will appear to move towards the objects A and B. In display 3a, B is in front of A. Both representations in the left-hand screen move to the right, but because object B is in front of A the representation of B moves further. The movements in the right-hand display are equal and opposite to those on the left-hand display.

Both representations increase in size by the same factor.

In Figure 4 if displays a and b are viewed consecutively, object B will appear to move upwards whilst remaining the same distance in front of object A. In this case, the representations of A do not move on the displays, but the representation of B in the left-hand display moves upwards and to the left whilst remaining the same size; the movement in the right-hand display is a mirror-image to this.

In Figure 5 if displays a and b are viewed consecutively, object B will move leftward whilst remaining the same distance in front of object A. In this case, the representations of object B on the left-hand and right-hand displays move equally leftwards without changing in size.

In Figure 6 if displays a and b are viewed consecutively, the viewer will appear to move leftwards whilst object B remains the same distance in front of object A. In this case, the representations of both objects A and B move equally to the right in both displays without changing in size but representation of A moves further than that of B.

It will be noted that the representations used in the above Figures are circular and the corresponding objects would appear spherical when viewed three-dimensionally through the binocular viewer. As spheres are the only shapes not affected by the rules of perspective, any other shape or object would require the computer programme which produces the signals forming the display to take account of changes in perspective in addition to the changes described above.

Referring to Figure 7 a three-dimensional video display apparatus 20 comprises a console 21 in which is mounted a television (TV) or video tube having an upwardly facing screen providing two displays separated by a vertical opaque wall 24a. A computer device 25 is arranged for playing a magnetic tape carrying a programme controlling the movements of one or more display symbols or representations on the displays 22, 23. Flat mirrors 24, 25 respectively reflect the images on the displays 22, 23 into the left-hand and right-hand lens systems 26, 27 of a binocular viewer device 28 arranged so that the left eye of a viewer sees only the image on the left-hand display 22 and the right eye of the viewer sees only the image on the right-hand display 23.The movements of the symbols on the two displays are controlled by the programme so as to produce relative movements of the symbols on the displays in the manner described above to produce a moving three-dimensional effect. The device 25 may include sound-reproducing means coordinated with the movements of the visual symbols and arranged to produce stereophonic sound through speakers such as 30 in housings 31,32. Instead of the tape a magnetic disc can be used.

It will be understood that relative movement between at least parts of the displays can be achieved by moving all or part of only one (either) display or all or part of both displays.

The view in display 22 and the view in display 23 are each viewed through only one eye and one or more parts of these views which are present in both views are displaced relative to each other to simulate three-dimensional movement of these parts relative to the background and/or viewer, or movement of the background and/or viewer relative to the parts, as described above. If the views are stationary, the viewer sees a stationary three-dimensional view. The views are produced electronically (real time).

The movements of some or all of the symbols may be under the control of the viewer through knob 35 and buttons or levers 33 operatively connected to the device 25 who thus provides an input to the device 25.

The screen is partly masked by an opaque wall 34. The console 20 may, as shown, be arranged for mounting on a wall. Control buttons 33' may enable a player to select a desired one of a plurality of games available from the device 25, and to select the number of players.

The programme may be arranged to move a background, as viewed through the viewer device, in a desired direction, for example to one side.

Using the rules described above in relation to Figures 1 to 6 and with a two display in the configuration described above, a typical game which could be played on the device would have the following programme if the purpose of the game were for the player/viewer to guide himself to a target without hitting any other objects displayed and within a time limit.

Programme The opening or initial display is shown in Figure 8.

Programme Conditions 1. If the representation or symbol cross coincides with the representation A, B, C or D the display is cleared, the game re-started by displaying the original display. Repeat three times.

2. If the cross coincides with the representation of a square, the display is cleared and the game re-started.

3. After two minutes the display is cleared and the game re-started. Repeat three times. The cross represents the player/operator, the square represents the target.

Programme Running Left display Right display Representation A Increase size, Increase size, move right move left Representation B (after Increase size, Increase size, 3 secs.) move right move left Representation C (after a Move leftwards Move leftwards further 3 secs.) Representation D (after a Move rightwards Move rightwards yet further 3 secs.) Repeat from Representation A Controls Lever 33 controls the representations.

Lever moved up: Representations A, B, C and D move downwards. The rate of descent increases proportionately for larger representations (nearer objects). Cross (Player) and Square (Target) remain stationary.

Lever moved down: Representations A, B, C and D move upwards. The rate of upward movement increases proportionately for larger representations. Cross and Square remain stationary.

Lever moved left. Representations A, B, C and D move right. The rate of rightwards movement increases proportionately for larger representations. Cross and square do not move.

Lever moved right. Representations A, B, C and D move left. The rate of leftwards movement increases proportionately for larger representations. Cross and square do not move.

Buttons or knobs 35 control forward and reverse. Left knob or button. All representations on display (except cross) increase in size and move rightwards on left display and leftwards on right display. Larger representations increase in size at a rate proportionately. Cross remains the same size and in the same position. Right knob or button. All representations on display (except cross) decrease in size and move leftwards on left display and rightwards on right display. Larger representations decrease in size and move leftwards or rightwards at a rate proportionately. Cross remains the same size and in the same position.

Successful Completion ofthe Game Square (target) is reached when sufficient forward movement without incident has been achieved to have caused the squares on the left and right displays to have increased in size and move rightwards and leftwards to a position where the crosses on the left and right displays are in the centres of their respective square as shown in Figure 9.

Figure 10 shows in perspective the three dimensional disposition of the cross, square and objects A, B, C, D as seen in the displays at the start of play (the initial display). The objects A, B, C, D are all the same size.

It wiil be understood that the apparatus may be used other than for playing a video game, for example it could be used for providing a three-dimensional presentation for use in training aircraft pilots.

Figure 11 shows a head set for use by an aircraft pilot. Signals from two spaced TV cameras, linked as above, on the aircraft represent the view ahead in three dimensions, as above, when viewed through the binocular viewer as shown in Figures 11,12. The electrical signals producing the visual representations are supplied on line 40 and the corresponding two display representations appear on the downwardly facing screen of TV tube 41,42 the representations being reflected to the viewer's eyes by mirrors 43. The pilot sees a three-dimensional view. Awall 44 Figure 12 ensures each eye sees only one display. Stereo sound may also be provided through speakers 45,46. The images on the screen may also include a display of instrument and other readings, similar to the so-called head-up display.The portion of the head-set housing the tubes and mirrors may be slidable upwards as shown dotted in Figure 11 to enable the pilot to see forwardly in the normal way, if desired. The cameras on the aircraft could be infra-red cameras to give improved visibility in certain circumstances.

Thus, in training a pilot in a flight simulator for example, a programmed magnetic tape could be used to provide a desired three-dimensional visual display, and a trainer/controller or the trainee pilot could operate controls to vary the visual display as desired, for example to simulate a sudden movement of part of the field of view of the pilot or a movement of the aircraft.

In Figure 13 a hand-held binocular viewer 50 includes a small TV tube providing displays 51, 52, respectively viewablethrough ports or lenses 53, 54 which are supplied with display signals through connector 55 leading to a programme device such as 25. Buttons such as 56, 57, 58 may be operated by a user to effect selected movements of the display to give a three-dimensional effect as above, operation of the buttons sending control signals to the programme device.

The invention may find application for example in the leisure, commercial or industrial fields. One example is in relation to aircraft. Another application of the invention might be for the control of aircraft in the airspace above an airport.

Information for Air Traffic Controllers is produced by a radar scanner, which indicates relative positions of aircraft to the airport and to each other. A signal from the aircraft identifies the aircraft and denotes its height from the ground. In a conventional display, this information is presented on a two-dimensional screen, with the aircraft represented as dots and their respective heights and code numbers shown numerically alongside. The controller infers the true positions in space by experience and directs aircraft movements accordingly.

Using apparatus arranged as described above for 3D viewing, the reflected signals, producing a display indicating the aircraft positions as though they were in a single plane relative to the airfield, would be modified electronically (item 25) by information from the various aircraft indicating respective heights, to produce new signals which when displayed in the dual manner described above, would give a moving three-dimensional display.

Aircraft identification codes would be presented numerically alongside the respective aircraft. The Air Traffic Controller (viewer) by operating controls linked to the signal-producing means (the device 25) as described, would be abie to alter his apparent position in space in relation to the objects displayed three-dimensionally, thereby improving his understanding of the real positions of the various aircraft in space.

In a more sophisticated arrangement, a computer could be linked to the display and be programmed to signal instructions to the aircraft, to achieve predetermined conditions, in response to the display or the signals forming the display.

A similar effect can be created by presenting an image formed by using two lenses attached to a camera respectively using red and green filters as described hereinbefore. When this image is presented on a single colour television screen and the viewer places red and green filters in front of the corresponding eyes a three-dimensional picture is created. This green/red method of presentation also can be combined with a computer programme as described earlier which allows the viewer to continuously alter the electronic signals to the programme and thus make a changing three-dimensional image on a single screen.

With the arrangements described a more realistic display is obtained than with a conventional two-dimensional display.

With an electronically-generated three-dimensional view, movable or changeable as described above, the objects may appear in front of the screen, with the screen if apparent forming a background. This is to be contrasted with a three-dimensional view obtained via a camera, in which the screen largely appears nearer than the objects; if the object appears to be in front of the screen it is more or less distorted: the camera can only "see" objects in front of it.

With an electronically-generated three-dimensional view there is no camera to act as an obstacle or limitation to forward movement of an object. With this method, the object furthest away from the viewer may in effect be the background.

Claims (13)

1. A method of producing a visual display comprising producing two simultaneous visual displays, and viewing the displays to obtain a stereoscopic view, input means changing at least part of one display relative to the other to change the view, the displays being on a single screen and non-overlapping.

2. A method as claimed in Claim 1, in which the displays are produced electronically.

3. A method as claimed in Claim 1 or Claim 2, in which the displays are side by side and the viewer sees only one display through only one eye and only the other display through only the other eye.

4. A method as claimed in any preceding claim comprising providing two visual displays on cathode-ray tubes means, providing means enabling said displays to be viewed in such a manner that one eye sees only one display and the other eye sees only the other display, and the viewer producing relative movement between at least parts of the displays in a manner such that when viewed through the enabling means a moving stereoscopic effect is produced.

5. A method as claimed in Claim 1 and substantially as herein before described.

6. Apparatus for producing a visual display comprising means for providing two simultaneous visual non-overlapping displays, means for viewing the displays to obtain a stereoscopic view, and input means operable to cause relative movement between at least a part of the displays to change the view, the displays being on a single screen.

7. Apparatus as claimed in Claim 6, in which the input means is adapted to be operated by a viewer.

8. Apparatus as claimed in Claim 6 or Claim 7, comprising cathode-ray tube means having a display screen, and the viewing means comprises means enabling the viewer to see only one display through one eye and only the other display through the other eye, and including means for providing signals to said tube means to form the displays.

9. Apparatus as claimed in any of Claims 6 to 8, in which the signal providing means comprises a magnetic tape.

10. Apparatus as claimed in any of Claims 6 to 8, in which the signal providing means comprises two cameras whose outputs are respectively connected to form the displays the outputs having a predetermined relation so as to simulate the displacement between a viewers' eyes.

11. Apparatus as claimed in any of Claims 6 to 10, comprising sound reproducing means operatively linked to the signal providing means.

12. Apparatus as claimed in any of Claims 6 to 11, in which the input means comprises a computer.

13. Apparatus for providing a visual display substantially as herein before described with reference to and as shown in Figure 7, or Figures 11 and 12, or Figure 13, of the accompanying drawings.