GB2392808A

GB2392808A - 3D enhancement optical system for display monitor

Info

Publication number: GB2392808A
Application number: GB0220544A
Authority: GB
Inventors: John Braithwaite; Eamonn Ansbro
Original assignee: RealView Innovations Ltd
Current assignee: RealView Innovations Ltd
Priority date: 2002-09-04
Filing date: 2002-09-04
Publication date: 2004-03-10
Also published as: WO2004023187A1; EP1636631A1; GB0220544D0; WO2004023187A8; AU2003269108A1

Abstract

The system comprises a fresnel lens 103 having a flat side 105 and a lensed side 104. The lensed side is positioned toward the display. The fresnel lens is curved along a horizontal axis, and angularly disposed or tilted along a vertical axis with respect to the projected visual display. A flexible optical element, such the fresnel lens may be held by adjustable tensioning members to tune the optical element (see figs 6-10).

Description

2392808:

3D ENHANCEMENT SYSTEM FOR MONITOR COMMUNICATIONS DEVICE

[1] Field of the Invention

[a] The present invention relates to opto-mechanical devices for use on video display units or monitors displaying 2 '/: D information, such as those typically employed in the fields of expert visualization data (e.g. medical imaging),

advertising, display, home computing, and computer games.

[31 BackOround [4] Three-dimensional graphics technology has experienced explosive growth in recent years. A significant contribution to this growth has been its adaptability to a wide spectrum of applications, not to mention the numerous advantages it provides over 2D. Currently, 3D graphics technology is used extensively in design-related applications, such as architecture and engineering. It is also used in scientific investigations, such as the re-creation of airplane crash disasters, and, in recreational-type activities, such as computer games, to name a few. The sophistication of these graphics afford an individual a realistic perspective of how various objects appear (and perhaps even dynamically inter-relate) in a virtual setting, thus providing an indispensable tool to a user of such graphics.

[5] Currently, one significant problem encountered with 3D graphics is the user's inability to properly interpret the relative depths of objects in 3D scenes (i.e., depth perception). This is primarily caused by the 3D graphics being projected onto a flat, two-dimensional computer screen, which severely limits the user's perception of this third dimension of 3D. As a result, the user cannot fully realize, and, thus

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appreciate, the depth of a 3D scene that makes these graphics more realistic or life-

like. [a] In the real world, depth perception is typically facilitated by movements that are sub-consciously performed by an individual, whether it is a subtle shift of the individual's body, head, or eyes. Such movements by the individual are commonly known as relative motion. However, although these subtle movements by the individual work in the real world for providing a better understanding of depth, such movements will not facilitate depth perception on conventional computer screens because the screens themselves are two-dimensional, and the light projecting therefrom reaches the right and left eyes at the same angle.

[a] In an attempt to overcome this difficulty in perceiving depth, a computer user will often change the orientation of a 3D graphics scene (e. g., by navigation) to gain the benefits of relative motion as experienced in the real world. However, this action inconveniences the user by placing the burden on him or her to provide such motion, especially if the user desires to remain static in the 3D scene to study a particular object. Moreover, while the user is trying to better interpret the 3D scene by engaging in navigation, he or she is distracted by concentrating more on the navigation process itself. That is, navigation requires the user to perform conscious acts (via a user-input device, for example) to provide this movement and is not sub consciously performed, as relative motion is performed in the real world.

[8] Typically, 3D graphics applications are designed with a variety of features to attempt to improve 3D simulation on a flat computer screen. These features include occlusion, shading, fog, size gradients, among others. However, although these

: e:... '.'::: features may improve depth perception in 3D scenes to some degree, they do not provide the user with a complete concept of depth in a quantitative manner, which is typically satisfied by relative motion in the real world.

[a] A good form of relative motion is the full duplication of the natural vision environment by providing a true 3D display. Such a display would permit the user to perform his or her natural psychomotor abilities (i.e., body, head, and eye movement) to obtain the relative motion necessary to properly interpret a 3D scene.

However, while these displays have been prototyped, their widespread use in the near future is unlikely. Furthermore, if and when these displays do become available, their cost is expected to be quite lofty, thus placing these displays out of the general public's reach.

[to] The present invention is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.

[hi] Visualization of 2 '/: D information has a depth perception based on perspective which has visual limitations. Use of enhanced left eye / right eye separation by the screen adds an illusion of depth, thus closely simulating a 3D image. [121 Summary of the Invention

[ha] The invention comprises a system for enhancing the image from a projected visual display comprising a fresnel lens having a flat side and a lensed side. The flat side is positioned toward the projected visual display. The fresnel lens is curved along a horizontal axis, and angularly disposed along a vertical axis with respect to the projected visual display.

À te c e 8 e e as 8 1 I e eeCel À c e À ee e e e c ce c e Be [141 Brief Description of the Drawinas

Us] Fig. 1 is a side view of monitor having a 3D enhancement system according to the present invention.

[46] Fig. 2 is a top sectional view of monitor having a 3D enhancement system according to the present invention.

[of] Fig. 3 is a side view of a monitor with a pivotal bracket supporting a screen framework. [18] Fig. 4 is a top section view showing the engagement of the fresnel lens within a mechanism for tuning the curvature of the fresnel lens.

[a] Fig. 5 is an embodiment of the present invention in which the fresnel lens is mounted in screen framework supported by a base that is detached from the monitor. [to] Fig. 6 shows an embodiment of the invention in which an optical element is held by a plurality of tensioning members.

[at] Fig. 7 shows a side sectional view of Fig. 6.

[ax] Fig. 8 is a cross sectional view showing one variety of engagement between a tensioning member and optical element.

[as] Fig. 9 shows an alternate embodiment for engaging a tensioning member with an optical element, in which the tensioning member 204 is fitted with a saddle 205. Fig. 10 shows an embodiment of the invention utilizing a rectangular optical element.

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rain Detailed Descrintion [25] [25] Referring now to Fig. 1 there is shown monitor housing 101 which contains monitor. It will be appreciated that the monitor can be of any conventional variety, such as a TV, or computer video tube or LCD screen. Any system for projecting an image is suitable. The monitor includes a monitor display screen 102. Spaced from monitor display screen 102 is fresnel lens 103. The lens collimates the light from monitor display screen. Fresnel lens 103 has two sides, flat side or surface 105 and lensed or grooved side 104. Fresnel lens 103 is angularly disposed (such as a 15 25 degree angle) along a vertical axis with respect to the projected visual display from monitor display screen 102, which is believed to reduce distortion of the image projected by monitor display screen 102. Finally, anti-reflective screen 103 is positioned distal monitor display screen 102. Anti-reflective screen 103 may be a conventional screed made of glass or plastic, such as those that achieve their anti reflective characteristics via a vacuum deposited fluoride, a technique well-known to those of skill in the art. Anti- reflective screen 103 is not mandatory to achieve the enhanced 3D effect, but it may provide an improved view depending on the ambient light conditions in which the invention is deployed.

[26] Fig. 2 is a top section view of monitor having a 3D enhancement system according to the present invention. From this view it will be appreciated that monitor screen 102 and anti-reflective screen 106 may have a generally flat surfaces, although a slight curvature is often used for monitor screens. In contrast, in accordance with the present invention, fresnel lens 103 is curved along a horizontal axis so that its vertical axis is further from the projected visual display than its side

À À e ce À e ece c À À ee ee. edges. In one embodiment, fresnel lens 103 may be a flexible 30 cm fresnel lens, available form Lenses, Ltd. of London England. This particular variety is comprised of flexible plastic, allowing a curvature to be imparted to the lens. In one embodiment, the amount of the curvature is such that the width of a 30 cm lens is reduced to 28 cm by virtue of the curvature. However, the precise amount of curvature may be adjusted to account for the desired extent of 3D effect. The curvature of fresnel lens 103 imparts a visual 3D effect from the display projected from monitor screen. It is believed that this 3D effect results from the alteration of the light waves so they are received by the left and right eyes of a viewer at slightly varied angles.

[at] Fig. 4 is a top section view showing the engagement of fresnel lens 103 within a mechanism for tuning the curvature of the fresnel lens 103. As noted above, it may be desirable to adjust the amount of curvature of fresnel lens 103 to achieve the optimal 3D enhancement for a particular viewer or monitor configuration. In one embodiment of the invention, this can be accomplished by sliding the side edges of fresnel lens 103 into a pair of fresnel lens securement frames 1 10 disposed on each side of the monitor. The fresnel lens securement frames are mounted in fresnel lens channels 109 which allow fresnel lens securement frames to move outward, toward monitor housing 101, or inward, toward the vertical axis of the monitor, by turning fresnel lens tuning knobs 107, which are threadedly secured monitor housing 101. Those of skill in the art will appreciate that because, as shown in Figs 1, 3 and 5, there are upper and lower tuning knobs 107 on each side of monitor housing, that the tension applied to the upper portion of fresnel lens 103 may be different than the

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À.e 6. 6 À À tension applied to the lower portion of fresnel lens. This allows the optical qualities of the system to be tuned to match the precise angle of inclination of fresnel lens 103 with respect to monitor display screen 102.

[28] Fig. 3 is a side view of a monitor with a pivotal bracket supporting a screen framework, which together comprise a structure attaching the fresnel lens to a housing containing a visual display projection system. The shown configuration utilizes bracket 116, monitor locking knob 111 and screen framework locking knob 112 to be easily adjust the angular disposition of fresnel lens 103 relative to the projected visual display from monitor display screen 102.

[zg] Fig. 5 is an embodiment of the present invention in which the fresnel lens is mounted in screen framework supported by a base that is detached from the monitor. Base 1 15 holds screen framework 1 13 via screen framework locking knob 112, which also provides pivotal adjustment of screen framework with respect to monitor display screen 102.

[so] Those of skill in the art will appreciate the desirability of providing a tunable optical element such as fresnel lens 103. However, the application of this concept can be broadly applied to systems other than 3D enhancement systems, and the concept of a tunable optical element as described herein is novel and non-obvious to those of skill in the art. Referring to Fig. 6, there is shown optical element 201 which may be, for example, a lens (including a fresnel lens), mirror, other any other similar device. Optical element 201 has an outer edge and central portion, and the outer edge engaged by a plurality of tensioning members (eight shown in this example). Tensioning members are threadably mounted in rigid frame 202. As

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À # e.. À tensioning members 203 are threaded into or out of frame, they exert a varying tensioning force of optical element 201. This tensioning force deflects the curvature of optical element 201, allowing its optical characteristics to be adjusted. Of course, those of skill in the art will appreciate that the amount of tension exerted by the tensioning members may vary; in other words, it is not required that all tensioning members exert an identical amount of force on optical element 201. This variation in forces can cause one area of optical element 201 to have different light transmissive or reflective properties than other areas of optical element 201. This allows optical element to be 201 to be tuned to create the desired optical effect, or to counteract optical abnormalities in other portions of the system in which optical element 201 is used.

[at] Those of skill in the art will appreciate that the present invention herein described may be supplemented with additional optical features. For example, a lenticular array may be positioned between the fresnel lens and the viewer, which would widen the field of view. Additionally, intermediate field variation optics may be

positioned between the monitor screen and the fresnel lens which can also serve to widen the field of view.

[as] Fig. 7 shows a side sectional view of Fig. 6. From this view, it may be appreciated that optical element is curved, having a generally concave configuration. As tensioning members 203 are screwed inward toward the central portion of optical element 201, they will cause optical element 201 to increase its curvature, which, in turn, alters its optical properties. Fig. 7 also shows how tensioning members 203 are held by rigid ring 202.

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[as] Fig. 8 is a cross sectional view showing one variety of engagement between tensioning member 203 and optical element 201. In this embodiment, optical element 201 has a V-shaped groove along its outer edge, which engages the tip of tensioning member 203.

[ad] Fig. 9 shows an alternate embodiment for engaging tensioning member 204 with optical element 201, in which tensioning member 204 is fitted with saddle 205.

[35] Fig.10 shows an embodiment of the invention utilizing rectangular optical element 207. Again, rigid frame 206 supports a plurality of tensioning members 203. [as] It will be understood that various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description is for illustration only, and not for the purpose of limitation, the invention

being defined by the claims.

Claims

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[3 Claims

[38] We claim: [39] 1. A system for enhancing the image from a projected visual display comprising: À A fresnel lens having a flat side and a lensed side The lensed side facing the projected visual display À The fresnel lens having side edges and being curved along a horizontal axis so that its vertical axis is further from the projected visual display than its side edges, and angularly disposed along a vertical axis with respect to the projected visual display.

[w]
2. The system of claim 1 further comprising: A structure attaching the fresnel lens to a housing containing a visual display projection system.

[at]
3. The system of claim 1 wherein: The fresnel lens is flexible, and further comprising: À Means for adjusting the amount of curvature of the fresnel lens.

[at]
4. The system of claim 1 further comprising: À Means for adjusting the angular disposition of the fresnel lens relative to the projected visual display.

[43]
5. The system of claim 1 further comprising:

J À ee. e e À À e e ce ee e e e e e e e Àee. e e e e - e e e e ee eve An anti-reflective screen positioned to receive a visual image projected by the fresnel lens.

[at]
6. A method of enhancing the image from a projected visual display comprising the steps of: À Passing the projected visual display through a fresnel lens having a flat side and a lensed side, wherein the fresnel lens is positioned so that the lensed side faces the projected display, and wherein the fresnel lens is being curved along a horizontal axis, and angularly disposed along a vertical axis with respect to the projected visual display.

[45]
7. A tunable optical element comprising: a flexible optical element having an outer edge; À a plurality of adjustable tensioning members wherein o each tensioning member engages a portion of the outer edge of the optical element, and o each tensioning member may be moved toward or away from the central portion of the optical element, such movement causing the optical element to flex to thereby alter its optical properties.

[46]
8. The tunable optical element of claim 7 further comprising: À a rigid frame surrounding the outer edge of flexible optical element and which holds the plurality of tensioning members.