GB2478358A

GB2478358A - Viewing device providing an increase in depth perception

Info

Publication number: GB2478358A
Application number: GB1003690A
Authority: GB
Inventors: Robert Black
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-03-05
Filing date: 2010-03-05
Publication date: 2011-09-07
Anticipated expiration: 2030-03-05
Also published as: GB201003690D0; GB2478358B

Abstract

A head mountable viewing device 10 has a support structure 12 so the device 10 can be worn on a users face in alignment with their eyes; a binocular disparity cancelling optical apparatus 26 having a lens 28, for example a prism, into which light from an image in front of a user enters and reflectors 30, 36, for example mirrored prisms 22,24 positioned to the left and right of the lens 28 and being in micro alignment with the lens 28. Light beams from an image that enter the lens 28 are split into two by the lens 28, one entering the left reflector 30, one entering the right reflector 36 and both being reflected to exit the device as two parallel light beams, one each from the left and right sides. The beams form an image to the eyes of a user which is without binocular disparity.

Description

An Optical Device

Technical field

[0001] The invention relates to a head mountable viewing device. The invention relates further to a head mountable viewing device which includes a binocular disparity cancelling optical apparatus for viewing images in three dimensions (3D).

Background art

[0002] The display and viewing of pictures in three dimensions (3D) has been known since the invention of the stereoscope. The stereoscope displays a different image to each eye, and the brain fuses these differences to form a single image. The fundamental component of stereoscopic 3D is binocular disparity which refers to the difference in image location of an object seen by the left and right eye of a human being, resulting from horizontal separation of the eyes.

The brain uses binocular disparity to extract depth information from the two-dimensional retinal images in stereopsis. In computer vision, binocular disparity refers to the same differences seen by two different cameras instead of eyes.

[0003] At any given time the line of sight of the left and right human eyes meet at a point in space. The point in space projects to the same location on the retina of each of the two eyes. Because of the different viewpoints observed by the left and right eye, many other points in space do not fall on corresponding retinal locations.

[0004] Microscopes which display a nearly identical image to each eye have been around since the late 17th century. Javal invented a device called the iconoscope, which reduced binocular disparity by a half, allowing observers to look at a picture without being aware of the surface. In 1907 Moritz von Rohr, an eminent figure at the Jena-based Carl Zeiss Werks, patented a synopter' device which was designed for the purpose of viewing pictures in more depth.

The synopter was rated as the most perfect and elegant design optically, but never entered production due to prohibitive production costs from over-engineering, and also the design being a cumbersome, heavy and unwieldy object at least as large as a Victorian parlour stereoscope, which proved unpopular and impractical to carry round art galleries.

[0005] The basic optical system of the synopter' device endured in microscopes and later telescope viewer attachments.

[0006] The Von Rohr patent, GB190700916A, entitled "Reflecting Intruments Annulling the Perception of Depth in Binocular Vision" contained several methods of implementing a "synopter" device. In these methods light is shown to enter through the front aperture and is split by a semi-silvered coating into two equal beams, which are doubly reflected by two sets of prisms to form two equal parallel beams of light 65mm apart (approximately human interpupilliary distance). A key feature of the design is that each eye sees an identical image, and that the eyes are not converging, but parallel, or diverged.

[0007] The disadvantages of the "synopter" device disclosed in Figure 8 of the Von Rohr patent are that it would not have worked to a satisfactory standard for an observer to obtain a convincing depth effect. The "synopter" device was also very expensive and had ergonomic issues as it was so large and cumbersome.

[0008] Further developments in this area were the Myopter viewer disclosed in US patent number 3,883,225, which was a small interocular device (55-60mm effective range) designed for use by children. The patent disclosed a therapeutic optical apparatus comprising an optical system for splitting and deflecting objective light, together with reflectors for reflecting the split portions of the light along parallel paths into the eyes of the patient, in avoidance of both convergence and stereopsis. Viewing lenses of the apparatus are matched to the patient's eyes and are provided with such power as to accommodate for close work.

[0009] Hegg described the high efficiency low glare x-prism in patent no. US5245472 (A). The patent disclosed a high efficiency x-prism beamsplitter for use in such applications such as helmet visor displays. The problem with the device disclosed in this patent is that the x-prism beamsplitter cannot be located very close to the wearer's eyes because of its shape. This shape therefore restricts its application to such applications as helmet visor displays and not direct application to a wearer's face and close to the eyes.

[0010] The advantage of the current invention is that there is room for the nose in the device and it can therefore be mounted on a person's face in closer proximity to the eyes. The device of the current invention is also lightweight and practical for extended wearing as a head mounted device, and it has a much larger field of view than known devices.

[0011] The device of the current invention also uses better materials, modern optical coatings for beam splitting and reflection limitation, and benefits from more advanced laser alignment techniques than were available previously.

Disclosure of the invention

[0012] According to a first aspect of the invention there is provided a head mountable viewing device comprising: -a support structure which is locatable on a user's face in alignment with the user's left and right eyes; -a binocular disparity cancelling optical apparatus being locatable by the support structure; -the binocular disparity cancelling optical apparatus comprising a first lens means operable to allow light from an image in front of a user, on whose head the viewing device is mounted, to enter the first leans means; at least one reflective surface being located on the left side of the support structure, and at least one reflective surface being located on the right side of the support structure; -the left and right reflective surfaces each being in micro alignment with the first lens means, and each light beam from an image that has entered the first lens means being operable to be split into two light beams by the first lens means, one of the light beams being operable to enter the left side of the support structure and the other light beam being operable to enter the right side of the support structure; and -each of the left and the right reflective surfaces being operable to reflect the two split light beams such that they are able to exit the support structure as two parallel light beams, one from the left side and the other from the right side of the support structure, the left and the right light beams providing an image which is substantially without binocular disparity to the left and right eyes of a user.

[0013] According to the invention there may be more than one left reflective surface located on the left side of the support structure and each of the left reflective surfaces are located in a second lens means, and there may be more than one right reflective surface located on the right side of the support structure and each of the right reflective surfaces are located in a third lens means.

[0014] Further according to the invention there may be more than one left reflective surface located on the left side of the support structure and these left reflective surfaces are located in a fourth and a fifth lens means, and there may be more than one right reflective surface located on the right side of the support structure and right reflective surfaces are located in a sixth and a seventh lens means.

[0015] Even further according to the invention the first lens means may be a first prism lens. Preferably this first prism lens is comprised of a right angled prism.

[0016] In one form of the invention the second and third lens means may each be in micro alignment with the first lens means. Further, the second and third lens means may be a second and third prism lens, respectively.

[0017] In another form of the invention the fourth, fifth, sixth and seventh lens means may be in micro alignment with the first lens means. Further, the fourth, fifth, sixth and seventh lens means may be a fourth, fifth, sixth and seventh prism lens, respectively.

[0018] In an even further form of the invention the distance between where the left split light beam is able to exit the support structure and where the right split light beam is able to exit the support structure may be adjustable.

[0019] According to the invention the split light beams from the image in front of the user and which exits the support structure are operable to enable a user to view the image with an increase in depth perception compared to the unaided depth perception of the user's eyes.

[0020] Further according to the invention the head mountable viewing device of the invention may be combined with a set of three-dimensional viewing glasses.

[0021] Typically the head mountable viewing device may be operable to view images such as pictures, paintings, computing displays, television screens, projector screens and the like, substantially without binocular disparity.

[0022] According to a second aspect of the invention there is provided a method of cancelling binocular disparity by means of a head mountable viewing device, the method comprising: -locating the device on a user's head, the device comprising a support structure which is locatable on a user's face in alignment with the user's left and right eyes, a binocular disparity cancelling optical apparatus being located by the support structure; -viewing an image with the binocular disparity cancelling optical apparatus of the device, the binocular disparity cancelling optical apparatus comprising a first lens means operable to allow light from an image in front of a user to enter the first lens means, at least one reflective surface being located on the left side of the support structure, and at least one reflective surface being located on the right side of the support structure, the left and the right reflective surfaces being in micro alignment with the first lens means, and each light beam from an image that has entered the first lens means being operable to be split into two light beams by the first lens, and one of the light beams being operable to enter the left side of the support structure and other light beam being operable to enter the right side of the support structure, and each of the left and the right reflective surfaces being operable to reflect the two split light beams such that they are able to exit the support structure as two light beams, one from the left side and the other from the right side of the support structure, the left and right light beams providing an image which is substantially without binocular disparity to the left and right eyes of the user.

[0023] According to the invention there may be more than one left reflective surface located on the left side of the support structure and each of the left reflective surfaces are located in a second lens means, and wherein there may be more than one right reflective surface located on the right side of the support structure and each of the right reflective surfaces are located in a third lens means.

[0024] Further according to the invention there may be more than one left reflective surface located on the left side of the support structure and these left reflective surfaces are located in a fourth and a fifth lens means, and wherein there may be more than one right reflective surface located on the right side of the support structure and right reflective surfaces are located in a sixth and a seventh lens means.

[0025] Even further according to the method of the invention the first lens means may be a first prism lens. Preferably this first prism lens is comprised of a right angled prism.

[0026] In one form of the invention the second and third lens means may each be in micro alignment with the first lens means. Further, the second and third lens means are a second and third prism lens, respectively.

[0027] In another form of the invention the fourth, fifth, sixth and seventh lens means may be in micro alignment with the first lens means. Further, the fourth, fifth, sixth and seventh lens means may be a fourth, fifth, sixth and seventh prism lens, respectively.

[0028] The method may further comprise adjusting the distance between the position where the left split light beam is able to exit the support structure and the position where the right split light beam is able to exit the support structure.

[0029] According to the method of the invention the split light beams from the image in front of the user and which exits the support structure are operable to enable a user to view the image with an increase in depth perception compared to the unaided depth perception of the user's eyes.

[0030] Further according to the method of the invention the head mountable viewing device of the invention may be combined with a set of three-dimensional viewing glasses for viewing an image.

[0031] Typically the head mountable viewing device may be operable to view images such as pictures, paintings, computing displays, television screens, projector screens and the like, substantially without binocular disparity.

Brief description of the drawings

[0032] The invention will now be described in more detail with reference to the accompanying drawings wherein: Figure 1 shows a schematic top view of a head mountable viewing device according to a first embodiment of the invention; Figure 2 shows a three dimensional view of a head mountable viewing device according to a second embodiment of the invention; Figure 3 shows a three dimensional view of a head mountable viewing device according to the second embodiment of the invention, including a first attachment means; Figure 4 shows a three dimensional view of a head mountable viewing device according to the second embodiment of the invention, including a second attachment means; Figure 5 shows a three dimensional view of a head mountable viewing device according to the second embodiment of the invention, including a third attachment means; Figure 6 shows a three dimensional view of a head mountable viewing device according to the third embodiment of the invention; Figure 7 shows a three dimensional view of a head mountable viewing device according to the third embodiment of the invention, including a first attachment means; Figure 8 shows a three dimensional view of a head mountable viewing device according to the third embodiment of the invention, including a second attachment means; and Figure 9 shows a three dimensional view of a head mountable viewing device according to the third embodiment of the invention, including a third attachment means.

Detailed description of the invention

[0033] A head mountable viewing device 10 according to a first embodiment of the invention is shown in Figure 1. The viewing device 10 comprises a support structure in the form of a housing 12 having a mounting means (not shown) such as a head strap, temple arms or the like for locating the device on a user's head and face.

[0034] The housing 12 has a rear portion 14 which is locatable on a user's face in alignment with the user's left eye 16 and right eye 18. Housing 12 further has a front portion 20 which faces away from a user's face and has an opening therein to allow light from an image in front of the user to enter the housing 12.

Housing 12 further includes a right side portion 22 and a left side portion 24.

[0035] As shown in Figure 1 binocular disparity cancelling optical apparatus 26 is located in the housing 12. The binocular disparity cancelling optical apparatus 26 is a double beam splitter which includes a first lens means in the form of a right angled first prism lens 28. It further includes at least two reflective surfaces 30, 32 which are located in the left side portion 24 of the housing 12, and at least two reflective surfaces 34, 36 which are located in the right side portion 22 of the housing 12.

[0036] The first prism lens 28 is located in the front portion 38 of the housing 12 and it is operable to allow light from an image in front of the user in the direction in which the user is facing to enter the front side 40 of prism lens 28.

[0037] The left reflective surfaces 30, 32 and right reflective surfaces 34, 36 are each in micro alignment with the first prism lens 28. As shown in Figure 1, the reflective surfaces 30, 32 are preferably located in a second prism lens 42 and the other reflective surfaces 34, 36 are preferably located in a third prism lens 44. The second prism lens 42 is located in the left portion 24 of the housing 12 and the third prism lens 44 is located in the right portion 22 of the housing 12.

In this case the second and third prism lenses 42, 44 are in micro alignment with the first prism lens 28. Such micro alignment may be accomplished by using laser alignment techniques. The second and third prism lenses 44, 46 may each be comprised of a single right angled triangle plus a square combined in one piece of material such as glass, or these pieces may be separate so that they are each adjustable for their IPD (interpupillary distance) as shown in Figures 6 to 9.

[0038] As shown in Figure 1, a beam of light from an image that has entered the front side 40 of the first prism lens 28 is then split into two light beams by prism lens 28. One of the split light beams being operable to enter the left side portion 24 and the other light beam being operable to enter the right side portion 22 of the housing 12. Each of the left 30, 32 and the right 34, 36 reflective surfaces of the second prism lens 42 and the third prism lens 44, respectively are operable to reflect the two light beams such that they are able to exit housing 12 as two substantially parallel beams one from the left side and the other from the right side of the housing 12, the left and right light beams providing an image which is substantially without binocular disparity to the left and right eyes of a user.

Thus the parallel light of two identical images exit the device 10, one image entering a user's left eye 16 and the other image entering the user's right eye 18 when the device is located on the user's head and in front of the user's face.

[0039] The split and reflected light from an image in front of a user and which exits the second and the third portions 24,22 of the housing 12 are operable to enable a user to view the image with an increase in depth perception compared to the unaided depth perception of the user's eyes. This is because of the fact that there is substantially no binocular disparity and both of the user's eyes can view an identical image. The advantage of this is that the image is viewed by the user with its natural implicit depth map. The result is that any image ever created or any image viewed by the user can look more three dimensional (3D), by removing the real depth information through the use of a head mounted device of the invention such as the illustrated in Figures 1 to 9. The cancellation of distracting surrounding information and removal of flatness from an image viewed results in a dramatically more vibrant and convincing 3D image viewed by the user.

[0040] A head mountable viewing device according to a second embodiment of the invention is shown in Figures 2 to 5. In Figure 2 to 5 a head mountable viewing device 46 comprises a support structure 48 which is locatable on a user's face in alignment with a user's left and right eyes. In Figure 3 the device 46 is shown to include a first attachment means in the form of flaps 50 and 52 which may be used to fold over a part of a pair of glasses, spectacles, sport goggles or the like. In Figure 4 the device 46 is shown to include a second attachment means in the form of temple arms 54 and 56 which are typically locatable on the sides of a user's head neat the temples. In Figure 5 the device 46 is shown to include a third attachment means in the form of a headband 58 which is locatable around a user's head.

[0041] A binocular disparity apparatus as described above with reference to Figure 1 is located by the support structure 48. In this second embodiment, however, the second and third prism lenses 42, 44 are each comprised of two separate parts.

The second prism lens 42 is itself comprised of a right angled prism lens 60 and another prism lens 62. The reflective surface 32 is provided by the right angled prism lens 60 and the reflective surface 30 is provided by prism lens 62.

[0042] In the same way the third prism lens 44 is itself comprised of a right angled prism lens 64 and another prism lens 66. The reflective surface 34 is provided by the right angled prism lens 64 and the reflective surface 36 is provided by prism lens 66.

[0043] A head mountable viewing device according to a third embodiment of the invention is shown in Figures 6 to 9. In Figure 6 to 9 a head mountable viewing device 68 comprises a support structure 70 which is locatable on a user's face in alignment with a user's left and right eyes. In Figure 7 the device 68 is shown to include a first attachment means in the form of flaps 72 and 74 which may be used to fold over a part of a pair of glasses, spectacles, sport goggles or the like. In Figure 8 the device 68 is shown to include a second attachment means in the form of temple arms 76 and 78 which are typically locatable on the sides of a user's head neat the temples. In Figure 9 the device 68 is shown to include a third attachment means in the form of a headband 80 which is locatable around a user's head.

[0044] A binocular disparity apparatus as described above with reference to Figure 1 is also located by the support structure 70. In this second embodiment, however, the second and third prism lenses 42, 44 are each also comprised of two separate parts. The second prism lens 42 in this embodiment is itself comprised of a right angled prism lens 82 and another prism lens 84. The reflective surface 32 is provided by the right angled prism lens 82 and the reflective surface 30 is provided by prism lens 62.

[0045] In the same way the third prism lens 44 is itself comprised of a right angled prism lens 86 and another prism lens 88. The reflective surface 34 being provided by the right angled prism lens 86 and the reflective surface 36 being provided by prism lens 88.

[0046] As shown in Figures 6 to 9, the third embodiment of the invention further has an adjustment means 90, by which the distance between where the left split light beam is able to exit the support structure 70, and where the right split light beam is able to exit the support structure 70, is adjustable. The way in which this may be done is that the user may be able to adjust the position of the prism lenses 84 and 88 sO that the left and right light beams enter the user's eyes correctly.

[0047] This double beam-splitting technique which is used in devices 10, 46 and 68 of the invention uses prism lenses which are preferably of glass and have a high refractive index. Each of the prism lenses also has silvered coatings so that their surfaces are reflective and/or refractive as the case may be. The first prism lens 28 preferably has a 50% silvered mirror coating 92 on its two back sides. The prism lenses 42, 44, 60, 62, 64, 66, 82, 84, 86 and 88 preferably have 100% silvered mirror coatings 94 on the inner reflective surfaces.

[0048] The devices 10,46 and 68 according to the illustrated embodiments of the invention are lightweight and practical for extended wearing as a head mounted device by the user. This is accomplished by the devices being constructed from modern materials, the use of modern optical coatings for beam splitting and reflection limitation, and benefits from more advanced laser alignment techniques than were previously available. Typically the head mountable viewing device may be used to view images such as pictures, paintings, computing displays, television screens, projector screens and the like, substantially without binocular disparity.

[0049] The effect of each of the devices 10, 46 and 68 work on a similar principle to the Magic EyeTM books, where the readers were told to diverge their eyes beyond the plane of the page. Doing this produced two results, a pop-out 3D sensation, and also a sense of deeper vision with the rest of the page diverged in space. It is this second effect which the devices exploit. Diverged eyes enable a calm, relaxed viewing experience of an image on a medium (e.g. page, canvas, computer or television screen). The lack of binocular disparity (or presence of parity) removes a conflict which most people are unaware of, that when the two eyes see their slightly different versions of a flat picture, the eyes have provided unambiguous flatness information about that page and its contents all being on the same plane. However, when this information is removed, by giving the observer only one perspective, the brain cannot tell (even though we still know consciously) where the true surface of the paper is. This unambiguous lack-of-flatness information is used by the brain to paint in a depth map based on the content of the image.

[0050] This invention exploits a known visual perception effect which is that when identical pictures are presented to each eye with no binocular disparity, an increase in depth relief is observed.

[0051] Use of a device of the invention, such as devices 10,46 and 68, demonstrates a further unexpected and previously unreported finding. The effect of using such a device in a wearable assembly whilst viewing a high definition computer display or television screen is one of dramatically improved motion sensation as it exploits the parallax cue in particular. An accompanying effect is an ability to visually interrogate all parts of the scene with the eyes relaxed thereby obtaining a greater feeling of immersion in the scene. This is not widely known due to the false baseline (i.e. the medium on which the image is presented) of the normal viewing experience.

[0052] Current commercially available head mounted displays and 3D glasses each have limitations. Firstly, for a head mountable 3D device to be sufficiently realistic, it must have a resolution of at least 400dpi due to proximity to the eyeball, which is sufficiently expensive to effectively exclude it from current mainstream consumer electronics. The devices of the invention retain all the detail of the real world, which is orders of magnitude higher than these available devices.

[0053] 3D glasses, be they anaglyph, shutter, or polarising, all have a common problem. The most popular method of 3D capture is using parallel cameras (converging at infinity), but due to observer eyestrain issues, there is no such convergence correction when they are projected or displayed on a screen, so the brain receives crude depth information that the objects presented are all in the near field. An analogy would be that a watch (disparity) can tell the time exactly, however, our own eyes (convergence) can inform us whether it is night or day. If convergence information does not agree with the disparity information, this creates a perceptual conflict between deciding what objects are distant objects and which are near objects. The devices of the invention may also be combined with a set of standard three-dimensional viewing glasses.

This combination with commercially available 3D glasses, would improve 3D perception by cancelling real-world flatness information about the screen, and also driving convergence beyond the plane of the screen to remove the rough distance cue. The binocular disparity cue would also be scaled, given that any disparities present when the eyes are looking at infinity would be interpreted as being very large, which would create a much greater stereo depth map.

[0054] As the device of the invention is made of lightweight materials such as polycarbonate and high density foam it can be made into or combined with a comfortable pair of spectacles, sport goggles or other head-mounted implementation.

[0055] It will also be understood that added depth effects can be gained by adding accommodative correction through two lenses or variable aperture pinholes to the front portion of a device of the invention.

[0056] Further changes can also be made to invention while to remaining with the scope of the invention. For example in order to keep the weight of the device excess glass may be chamfered away from the prisms. Other suitable materials such as acrylic may be used to form the prism. Mirrors lens may be used instead of or in combination with the prisms.

Claims

Claims 1. A head mountable viewing device comprising: -a support structure which is locatable on a user's face in alignment with the user's left and right eyes; -a binocular disparity cancelling optical apparatus being locatable by the support structure; -the binocular disparity cancelling optical apparatus comprising a first lens means operable to allow light from an image in front of a user, on whose head the viewing device is mounted, to enter the first lens means; -at least one reflective surface being located on the left side of the support structure, and at least one reflective surface being located on the right side of the support structure; -the left and right reflective surfaces each being in micro alignment with the first lens means, and each light beam from an image that has entered the first lens means being operable to be split into two light beams by the first lens means, one of the light beams being operable to enter the left side of the support structure and the other light beam being operable to enter the right side of the support structure; and -each of the left and the right reflective surfaces being operable to reflect the two split light beams such that they are able to exit the support structure as two light beams, one from the left side and the other from the right side of the support structure, the left and right light beams providing an image to the left and right eyes of a user which is substantially without binocular disparity.
2. A head mountable viewing device as claimed in claim 1, wherein there is more than one left reflective surface located on the left side of the support structure and each of the left reflective surfaces are located in a second lens means, and wherein there is more than one right reflective surface located on the right side of the support structure and each of the right reflective surfaces are located in a third lens means.
3. A head mountable viewing device as claimed in claim 1, wherein there is more than one left reflective surface located on the left side of the support structure and these left reflective surfaces are located in a fourth and a fifth lens means, and wherein there is more than one right reflective surface located on the right side of the support structure and right reflective surfaces are located in a sixth and a seventh lens means.
4. A head mountable viewing device as claimed in claim 1, wherein the first lens means is a first prism lens.
5. A head mountable viewing device as claimed in claim 4, wherein the first prism lens is a right angled prism.
6. A head mountable viewing device as claimed in claim 2, wherein the second and third lens means are each in micro alignment with the first lens means.
7. A head mountable viewing device as claimed in claim 2, wherein the second and third lens means are a second and third prism lens, respectively.
8. A head mountable viewing device as claimed in claim 3, wherein the fourth, fifth, sixth and seventh lens means are in micro alignment with the first lens means.
9. A head mountable viewing device as claimed in claim 3, wherein the fourth, fifth, sixth and seventh lens means are a fourth, fifth, sixth and seventh prism lens, respectively.
10. A head mountable viewing device as claimed in any of the preceding claims, wherein the distance between where the left split light beam is able to exit the support structure and where the right split light beam is able to exit the support structure is adjustable.
11. A head mountable viewing device as claimed in any of the preceding claims, wherein the split light beams from the image in front of the user and which exit the support structure are operable to enable a user to view the image with an increase in depth perception compared to the unaided depth perception of the user's eyes.
12. A head mountable viewing device as claimed in any of the preceding claims, which is combined with a set of three-dimensional viewing glasses.
13. A method of cancelling binocular disparity by means of a head mountable viewing device, the method comprising: -locating the device on a user's head, the device comprising a support structure which is locatable on a user's face in alignment with the user's left and right eyes, a binocular disparity cancelling optical apparatus being located by the support structure; -viewing an image with the binocular disparity cancelling optical apparatus of the device, the binocular disparity cancelling optical apparatus comprising a first lens means operable to allow light from an image in front of a user to enter the first lens means, at least one reflective surface being located on the left side of the support structure, and at least one reflective surface being located on the right side of the support structure, the left and the right reflective surfaces being in micro alignment with the first lens means, and each light beam from an image that has entered the first lens means being operable to be split into two light beams by the first lens, and one of the light beams being operable to enter the left side of the support structure and other light beam being operable to enter the right side of the support structure, and each of the left and the right reflective surfaces being operable to reflect the two split light beams such that they are able to exit the support structure as two parallel light beams, one from the left side and the other from the right side of the support structure, the left and right light beams providing an image which is substantially without binocular disparity to the left and right eyes of the user.
14. A method as claimed in claim 13, wherein there is more than one left reflective surface located on the left side of the support structure and each of the left reflective surfaces are located in a second lens means, and wherein there is more than one right reflective surface located on the right side of the support structure and each of the right reflective surfaces are located in a third lens means.
15. A method as claimed in claim 13, wherein there is more than one left reflective surface located on the left side of the support structure and these left reflective surfaces are located in a fourth and a fifth lens means, and wherein there is more than one right reflective surface located on the right side of the support structure and right reflective surfaces are located in a sixth and a seventh lens means.
16. A method as claimed in claim 13, wherein the first lens means is a first prism lens.
17. A method as claimed in claim 16, wherein the first prism lens is a right angled prism.
18. A method as claimed in claim 14, wherein the second and third lens means are each in micro alignment with the first lens means.
19. A method as claimed in claim 14, wherein the second and third lens means are a second and third prism lens, respectively
20. A head mountable viewing device as claimed in claim 15, wherein the fourth, fifth, sixth and seventh lens means are in micro alignment with the first lens means.
21. A head mountable viewing device as claimed in claim 15, wherein the fourth, fifth, sixth and seventh lens means are a fourth, fifth, sixth and seventh prism lens, respectively.
22. A method as claimed in any of claims 13 to 21, which further comprises adjusting the distance between the position where the left split light beam is able to exit the support structure and the position where the right split light beam is able to exit the support structure.
23. A method as claimed in any of claims 13 to 22, wherein the split light beams from the image in front of the user and which exits the support structure are operable to enable a user to view the image with an increase in depth perception compared to the unaided depth perception of the user's eyes.
24. A method as claimed in any of claims 13 to 23, wherein the head mountable viewing device is combined with a set of three-dimensional viewing glasses.