WO2009134228A1

WO2009134228A1 - Improved apparatus for creating brighter illusions

Info

Publication number: WO2009134228A1
Application number: PCT/US2008/005674
Authority: WO
Inventors: Gary Nicholson Baker
Original assignee: Gary Nicholson Baker
Priority date: 2008-05-02
Filing date: 2008-05-02
Publication date: 2009-11-05
Also published as: EP2276545A1

Abstract

The present invention relates to a system for projecting images through a beam splitter arrangement (20,22,24) in the fashion of a 'Peppers Ghost'. A novel beam splitter pack is also taught in which multiple beam splitter layers (20,24,26) are combined to form a pack which when employed in the subject system, results in a greatly enhanced image of great brightness.

Description

IMPROVED APPARATUS FOR CREATING BRIGHTER

ILLUSIONS

[0001] The present invention relates generally to systems for creating illusions in the manner of what has become known in the industry as Pepper's Ghost and is intended to provide apparatus which is capable of providing significantly brighter images than apparatus and systems currently available.

BACKGROUND OF THE INVENTION

Field of the Invention

[0002] Since at least the 1860's, entertainers, sometimes referred to as magicians, or illusionists, have been delighting and mystifying their audiences by making objects appear where they are not. One of the more common illusions involved the magical appearance of a deceased person, or a person believed to be in a remote location.

Overview of the Related Prior Art

[0003] The creation of illusions by merger of mechanical and optical devices is believed to have been the brain child of one Henry Dirks who created the Dirksian Phanstasmgoria in about 1862. John Pepper and James Walker made the basic process famous with their patent number 221,605, issued in 1879, and which has become known, euphemistically, as "Pepper's Ghost".

[0004] Pepper and Walker envisioned a large glass plate disposed on stage at an angle relative to the audience. A light source is strategically positioned so as to cause a portion of the light source to be reflected of the glass plate, while another portion passes through the glass. By so doing, the light source [usually an image of an object or person] can be made to appear and to appear in places where it is not.

[0005] After a substantial hiatus, others found applications for the underlying concept, e.g, video conferencing, desktop projection systems and teleprompters. McNelley et al, e.g., issued a family of patents such as 5,639,151 and 5,777,665, together with continuations on each.

[0006] Machtig, who joined with McNelley on several of the aforementioned patents, also caused others to issue, e.g., 5,582,547, 5,923,469 and their progeny. All of the McNelley and Machtig patents are assigned to Videotronics Systems, and all appear to employ a single transparent/reflective beam splitter element which is at the root of the Pepper's Ghost concept, as employed in a variety of modern image transmitting equipment.

[0007] Rogers ventured into the industry with his patent 4,805,895 which provides means for projecting virtual images to an audience in a theater setting, and Melville, in his patent 6,257,727 provides a similar focus.

[0008] Finally, O'Connell, et al. publication number US2007/0201004, is a Pepper's ghost variation, which also includes a tensioning system. It is also suggested, but not detailed in Maass, et al. patent number 5,865,519. That tensioning system is indicative of the old art, over which the present invention constitutes a distinct improvement.

[0009] In summary, there is a wealth of prior art directed to different uses for the basic principals espoused in Pepper. There is a paucity of art, however, directed to improving the performance of the various systems.

SUMMARY OF THE INVENTION

[0010] The complaint heard most among those who regularly use beam splitter technology in various communication and entertainment devices, is the lack of adequate brightness of the reflected image. This is especially true in those devices where the beam splitter is very large. It is a fundamental objective of the present invention to provide significantly improved brightness of the images projected by the beam splitter apparatus.

[0011] More specifically, and related to the foregoing, it is an objective of the present invention to create an improved beam splitter which is capable of emitting brighter and more vivid images.

[0012] Yet another objective of the present invention is to create a system, at the root of which is an array of beam splitter elements arranged in a pack, which provides the user with a significant savings in power requirements and related costs to use the system.

[0013] Another, and further, objective is to provide a system, which includes a beam splitter pack which is exceptionally strong when placed in prolonged tension so that wrinkles and waves can be minimized and in which the virtual images projected appear brighter, more vivid and realistic than is currently possible.

[0014] The foregoing, as well as other objects and advantages of the present invention, will become apparent to those skilled in the art from a reading of the forthcoming Detailed Description of a Preferred Embodiment taken in conjunction with the drawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 is a graphic representation of a basic beam splitter arrangement which embodies the essential improvement in the beam splitter element;

[0016] FIG. 2 is a perspective of an improved beam splitter element constructed in accordance with the present invention;

[0017] FIG. 3 is a pictorial representation of the "Pepper's Ghost" concept which is at the heart of the improved system herein described;

[0018] FIG. 4 is a portion of a rigid tensioning system, partially sectioned and with the understanding that there is an opposite end which is substantially identical but reversed from FIG. 4;

[0019] FIG. 5 is a portion of a flexible tensioning system, partially sectioned and with the understanding that there is an opposite end which is substantially identical but reversed from FIG. 5; and, [0020] FIG. 6 illustrates a complete tensioning system in which the left end is in the form of the rigid tensioning system, whereas the opposite side is of the flexible system.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0021] Illusionists and magicians have, since time immemorial, been regaling their audiences with seemingly unexplainable appearances of virtual images of such things as long dead relatives or unnatural floating objects.

[0022] In most cases, the answer merely requires a nominal understanding of optics and the propagation of light. Enter John Pepper and his colleague, James Walker, who, in August of 1869 sought patent protection on a system they had devised to amaze and beguile audiences with such mystic appearances. In modern parlance, that has become known as "Pepper's Ghost".

[0023] Referring initially to FIG. 3, the environment in which the present invention has particular, although not exclusive, utility is graphically illustrated and is reflected in two aspects, the first being a vastly improved beam splitter, and, secondly, a substantially enhanced stage or like performances. [0024] RG. 3 reflects the layout envisioned by Pepper et al. The key feature in that scenario is the beam splitter D, which pepper characterized as having graduated opacity. By moving the beam splitter diagonally across the stage to a position shown in dotted lines, and slanting that beam splitter at an appropriate angle [typically 45E] relative to the audience, the audience is able to see the object OR behind the beam splitter. At the same time, an object OF forward of the beam splitter would be perceived to appear adjacent to the rear object.

[0025] By virtue of the beam of light emitted from the forward object, a portion of that beam would be reflected in the mirrored portion of the beam splitter, back toward the audience. At least some of the beam passes through the beam splitter with a result that the brightness of the image is lessened to a significant extent. As a consequence, the ability to provide sharp, cognizable and, perhaps, above all, believable, images to an audience is materially impaired, together with the anticipated entertainment value.

[0026] While seemingly of minimal significance, the loss of brightness in many settings and, in particular, large stage environments where the audience is relatively remote from the light sources, the problem is significant and, in extreme settings, renders a performance, as a practical matter, impossible.

[0027] Thus far, the industry has responded by offering high powered projectors for light sources, with a coincident substantial increase in costs. The present invention is intended to teach an alternative to the need for high tech, high cost equipment.

[0028] Reference is made to FIG. 1, which graphically depicts the preferred embodiment of the beam splitter structure, presenting a split beam structure which demonstrates, as part of a system for creating ghost like images of greatly increased brightness and, in a large setting, a commensurate increase in audience enjoyment.

[0029] Beam splitters, generally, and, in particular, in a stage setting where a substantial audience is anticipated to be present, may be of very considerable dimension, measured in feet, not inches. From the standpoint of appropriate material, it is typically of a clear substance, e.g., plate glass, optically neutral acrylics and polymeric films and some synthetic scrims. [0030] Still referring to FIG. 1, layers of substantially identical beam splitter elements 20, 22 and 24 are shown as being coplanar. Beam splitter element 20 is numbered 1, beam splitter element 22 is numbered 2 and beam splitter element 24 bears the symbol ^WX\ The symbol "X" is intended to represent an integer between 3 and some larger number up to some practical limit, and the designation is intended to indicate that the number of layers of beam splitter material is, within practical limits, a matter of intelligent choice.

[0031] Each beam splitter element has a face surface 26 and a back, or rear, surface 28, and that is true no matter how thin each layer may be. The significance of that simple fact becomes apparent when a light source 31 is positioned such that the beam of light 33 impinges [incident] on the face 26 of each of the beam splitters at an appropriate angle ∑ [omega] resulting in a portion of the beam 35 [reflective] being split, and directed toward the viewers eye E. Coincidently, another portion of the beam 31 continues on to impinge on the inner surface of the rear surface 28, where a portion of it is also reflected toward the viewers eye E along the path at 37.

[0032] In fulfilment of the objectives of the present invention, two or more layers of beam splitter elements are arrayed in face to back touching arrangement, joined in a pack such as seen at 39 in FIG. 2. As will be seen in FIG. 2, every layer of beam splitter material must remain absolutely flat with relatively few waves or wrinkles, since a light wave hitting a surface which is not at the proper angle to the wave will result in at least a portion of the wave being reflected in the wrong direction.

[0033] The concept of achieving a perfectly flat [or at least as flat as can be achieved] array of beam splitters in a pack perhaps seems a simple matter. However, when one considers that a pack may be ten to twenty feet high, or more, and at least that wide, the scope of the problem becomes apparent. It is further exacerbated by the reality that each beam splitter, far from rigid, would most typically be a few mills thick and highly flexible, and combining a few of them in a pack does not ameliorate the situation by creating sufficient stiffness as to maintain the requisite stiffness and wrinkle free attitude without additional apparatus to assist.

[0034] In addition to being essentially wrinkle free, each layer must be immediately adjacent to and touching the adjacent layer. The present view of the invention is that even seemingly optically clear adhesives currently available may tend to neutralize or distort light waves in the inner reaches of the beam splitter pack where an adhesive is in use and, thus, are not presently as effective in assembling a pack as, e.g., engaging the perimeter of the pack to remove possible non uniformity of the plane of the layers which comprise the pack.

[0035] Accordingly, and in furtherance of the objectives of the invention, perimeter clamps 42 are shown and intended to be illustrative of a means, although clearly not the means, of assuring that the layers which comprise the pack are uniformly flat and wrinkle free.

[0036] Thus, and with specific reference to FIGS. 4, 5 and 6, an exemplary tensioning system is illustrated in some detail. The system has as its purpose the application of a uniform tension across the entire surface of a pack of beam splitter elements 39 so as to establish the pack as a fully controlled, unitary, relatively wave and wrinkle free beam splitter pack, usable in any environment in which a beam splitter has utility. Referring initially to F IG. 4, a relatively rigid tensioning support system 48 is illustrated in some detail.

[0037] A clamp 42 is shown as comprising a pair of jaws 50, 51. Each jaw is fitted with a slip resistant gripping pad 53, secured to a rigid backing member 55. The entire edge of the beam splitter pack is uniformly engaged in gripping relation in the jaws 50, 51 between the pads 53. The jaws themselves are secured relative to each other in a "ITchannel beam 57 by means of at least one bolt 59, which can be adjusted with nut 62 to assure that appropriate gripping pressure can be created uniformly across the entire length of the jaws 53, between the post 64, which is fixed and the "IT'channel beam 57. It will be understood that the post is but representative of any stationary member which serves to hold the jaws in a relatively fixed position.

[0038] It will be appreciated that the tensioning system 48 provides uniform pressure on the beam splitter pack along its opposed entire edges. The same tensioning system can be deployed at opposite edges to hold the pack as substantially wrinkle and wave free as reasonably possible given the state of the art. The system creates uniformity of tension at the "l/'channel beam, which is held against a rigid post 64 by a bolt 66, one end of which is secured to the stationary post 64, and the other end being engaged in the "ITchannel beam, and its length is variable by adjustment with the nut 68, to determine tension on the pack.

[0039] FIG. 5 provides an alternative to the rigid system 48. Thus, a flexible system 71. The clamping arrangement of the flex system 71 is essentially the same as that of the rigid system 48. The difference rests with at least one pair of flexible bands 73 which are affixed at one end in the clamps 55, which, coincidently, hold the entire length of the edge of the beam splitter pack 39. The opposite end of the bands 73 are held between the blocks 75, held in clamping relation by an adjustable cross bolt 77. By providing limited flexibility and, thus, limited relaxation of the tension on the beam splitter pack, the bands between the jaws and the "ITchannel beam, potential for damage to the beam splitter pack is minimized.

[0040] Those skilled in the art will appreciate that an operator may use the rigid system 48 or the flex system 71 on either or both ends. It will also be appreciated that other tensioning devices, and/or tensioning means, within each device will occur to those who study this disclosure, all of which are within the contemplation of the invention.

[0041] Returning to FIG. 1, the system includes another light source 45 located on the opposite side of the pack from the viewer E, allowing the viewer to see the light source 45 directly through the pack. The light source 31 will simultaneously visually appear at 47 as though it is adjacent the light source 45 by virtue of the reflection of a portion of the beam of light emanating from the light source off both the face and rear surfaces, 26, 28, of each of the several beam splitters 20, 22, and 24.

[0042] Moreover, and most significantly, the image of the light source 31 will appear substantially brighter than the same image as it would appear as reflected off a single beam splitter. Indeed, with the addition of each layer of beam splitters in a pack, brightness of the image is increased as much as 100%, slightly diminished only by material transmission haze and other optical loss factors.

[0043] While the preferred embodiment of the invention has been shown and described with respect to a particular structure, those skilled in the art will perceive that alternative elements of the structure may exist, which when substituted for those described, may offer the same result. It will be understood that such alternatives are within the contemplation of the invention as described in the accompanying claims, wherein:

Claims

1. A beam splitter pack comprising an array of beam splitter elements; each said beam splitter element is constructed of a transparent/reflective material, and having a front surface and a back surface; said beam splitter elements being arranged in a face-to-back contact, whereby the projection of an image into said beam splitter pack is reflected with increased brightness.

2. The beam splitter pack of Claim 1, wherein said beam splitter pack is maintained in tension so as to substantially remove wrinkles and waves in said beam splitter elements.

3. The beam splitter pack of Claim 1, wherein said beam splitter pack includes at least 2 beam splitter elements.

4. The beam splitter pack of Claim 2, wherein said beam splitter pack includes at least 2 beam splitter elements.

5. Apparatus for use in creating an improved virtual image of enhanced brightness, placing the same relative to a physical image, the entire scene to be viewed by an audience, said apparatus including a beam splitter pack; a light source, said light source projecting an image on to said beam splitter pack at an angle relative thereto; said beam splitter pack comprising an array of beam splitter elements; each said beam splitter element is constructed of a transparent/reflective material, and having a front surface and a back surface; said beam splitter elements being arranged in a face-to-back contact, whereby the projection of an image into said beam splitter pack is reflected with increase brightness; said beam splitter pack being tensioned to substantially remove wrinkles and waves therein.

6. The apparatus of Claim 5, having jaws; said jaws uniformly engaging said beam splitter pack along remote edges thereof to thereby create a uniform tension on said beam splitter pack.

7. The apparatus of Claim 6, each of said jaws being adjustably secured to a stationary post so as to permit adjustment to the amount of tension applied to said beam splitter pack.

8. The apparatus of Claim 6, wherein said jaws are positioned within a bracket; and the tension on said jaws holding the remote edges of said beam splitter pack is adjustable.

9. The apparatus of Claim 8, wherein a bolt connects said bracket and said post, the length of said bolt being adjustable to adjust the tension on said bracket.

10. The apparatus of Claim 8, wherein a flexible band is interposed between said bracket so as to permit limited relaxation of the tension on said beam splitter pack as needed.