Abstract:
A method and apparatus for use in connection with a theatrical stage presentation for rendering an actor or object located on the stage visible or invisible at will. The apparatus used to create the illusion includes a strategically located, selectively transparent screen and a large, generally vertically extending mirror. In carrying out the method of the invention, the mirror is controllably moved across the stage at a location intermediate a rear wall and the selectively transparent screen from a first position out of sight of the audience to a second position wherein the mirror is disposed between the rear wall and the selectively transparent screen.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to theatrical productions. More particularly, the invention concerns a method and apparatus for producing optical illusions. 
         [0003]    2. Discussion of the Prior Art 
         [0004]    A number of methods and apparatus for producing optical illusions have been suggested in the past. A very early apparatus of this type was disclosed by Pepper and Walker in U.S. Pat. No. 221,605 that was first patented in England in March of 1879. Pepper and Walker suggested an arrangement of apparatus to render an actor or object gradually visible or invisible at will and also to substitute for an object in the sight of the audience the image of another similar object hidden from direct vision without the audience being aware that any such substitution had been made. At the heart of the Pepper and Walker apparatus was a large plate of glass which was transparent and more and more densely silvered in passing from one end toward the other end. The plate glass was placed diagonally across the stage so that as it was advanced the glass obscured the view of the actor or object in front of which it passed and substituted the reflection of an object in front of the glass, but suitably concealed from the direct view of the audience. 
         [0005]    In recent years, a number of different types of apparatus have been suggested for performing optical illusions both on stage and in the media of television and motion pictures. These apparatus tend to be quite elaborate and are typically complex and usually quite expensive. The thrust of the present invention is to provide a method and apparatus for performing optical illusions that is of a simple construction and one that can be relatively inexpensively constructed and easily set up for performing optical illusions on a conventional theatrical stage. However, the apparatus can be readily adapted for use in other performing media. 
       SUMMARY OF THE INVENTION 
       [0006]    By way of brief summary, a principal object of the present invention is to provide a method and apparatus for use in connection with a theatrical stage presentation for rendering an actor or object located on the stage visible or invisible at will. 
         [0007]    In one form of the apparatus of the invention a strategically located, selectively transparent screen and a large, generally vertically extending mirror are used to create the illusion. In accordance with one form of the method of the invention the mirror is controllably moved across the stage at a location intermediate a rear wall and the selectively transparent screen from a first position out of sight of the audience to a second position wherein said mirror is disposed between the rear wall and the selectively transparent screen. 
         [0008]    With the forgoing in mind, it is an object of the present invention to provide a method and apparatus for creating an optical illusion wherein actors or other objects on the stage are made to appear to magically vanish. 
         [0009]    Another object of the invention is to provide an apparatus of the aforementioned character which is of a simple, straightforward construction and easy to set up and use. 
         [0010]    Another object of the invention is to provide an apparatus as described in the preceding paragraphs which is relatively inexpensive and is adapted to be used on a conventional theatrical stage. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a front view of the theatrical stage upon which the illusion is performed. 
           [0012]      FIG. 2  is a cross-sectional view taken along lines  2 - 2  of  FIG. 1 . 
           [0013]      FIG. 3  is a view taken along lines  3 - 3  of  FIG. 2 . 
           [0014]      FIG. 4  is a cross-sectional view taken along lines  4 - 4  of  FIG. 3 . 
           [0015]      FIG. 5  is a view taken along lines  5 - 5  of  FIG. 2 . 
           [0016]      FIG. 6  is an enlarged cross-sectional view taken along lines  6 - 6  of  FIG. 5 . 
           [0017]      FIG. 7  is a fragmentary view similar to the central portion of  FIG. 2  but showing the mirror having been moved from the left side of the stage to the right side of the stage. 
           [0018]      FIG. 8  is a view taken along lines  8 - 8  of  FIG. 7 . 
           [0019]      FIG. 9  is an enlarged cross-sectional view taken along lines  9 - 9  of  FIG. 8 . 
           [0020]      FIG. 10  is an enlarged cross-sectional view taken along lines  10 - 10  of  FIG. 8 . 
           [0021]      FIG. 11  is a generally diagrammatic, top plan view further illustrating the method of carrying out the illusion of the invention. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0022]    Referring to the drawings, and particularly to  FIGS. 1 through 4 , one form of the apparatus of the invention for performing an optical illusion can be seen to comprise a stage  14  that is viewable by an audience “A” (see also  FIG. 11 ). As best seen by referring to  FIG. 2 , stage  14  has a width “W”, a forward portion  16 , a rear wall  18  and a transversely extending line  20  that is disposed between the forward portion  16  and the rear wall  18 . The portion of the stage that is directly viewable by the audience is identified in  FIG. 1  by the numeral  22  and is defined by a decorative superstructure  24  that is located proximate each side of the stage. 
         [0023]    As illustrated in  FIG. 2 , the rear wall  18  of the stage has a first image  26  formed thereon. This first image, which can be formed on the wall itself, or on a scrim panel, can comprise a decorative scene, a distinctive pattern, a particular texture, or similar image that is readily recognizable by the audience. 
         [0024]    Disposed out of sight of the audience and partially behind a portion of the superstructure  24  is a generally vertically extending mirror  28 . Mirror  28 , which has a reflective front surface  28   a , is controllably movable along transversely extending line  20  from a first position out of sight of the audience (see  FIG. 2 ), to a second extended position (see  FIGS. 7 and 8 ). Mirror  28 , which is preferably relatively thin having a thickness of between about ¼ and about ⅜ inch, can be quickly and noiselessly moved across the stage by running it in guides and upon rollers or the like in a manner well understood by those skilled in the art. 
         [0025]    Positioned between the audience “A” and the generally vertically extending mirror  28  is a selectively transparent, perforated screen, or scrim  30 , which is of a character well known to those skilled in the art. Screen  30 , which is maintained substantially parallel to mirror  28 , has a front surface  30   a  and a rear surface  30   b  that is provided with a second image  32  that generally corresponds to the mirror image of the first image  26  that is formed on rear wall  18 . More particularly, as will be discussed in greater detail in the paragraphs which follow, image  32  is formed on rear surface  30   b  of the scrim in a manner such that when the mirror  28  is moved across the stage and the image  32  is reflected from the front surface  28   a  of the mirror, the audience will believe that they are at all times seeing the rear wall of the stage rather than the reflection of the image formed on the scrim  30 . 
         [0026]    For a purpose presently to be described, the apparatus of the present embodiment of the invention further includes first and second light sources  34  and  36  that are mounted on the stage superstructure in a manner to selectively illuminate the stage and the front and rear surfaces  30   a  and  30   b  respectively of the screen  30  (see  FIG. 11 ). 
         [0027]    Referring particularly to  FIGS. 1 ,  2 ,  3  and  11 , during the performance of the optical illusion, several objects of different character are strategically positioned on the stage. These objects here include a first object  38 , depicted as a person that is positioned between the transversely extending line  20  and the rear wall  18  of the stage. A second object, here depicted as an article of furniture in the form of a chair  40  of unique design, is positioned at a location proximate the right side of the stage. Uniquely, chair  40  is bisected so that its first side portion  40   a  is disposed on one side of the transversely extending line  20  and its second side portion  40   b  is disposed on the opposite side of the transversely extending line  20 . 
         [0028]    As best seen in  FIGS. 2 and 10  of the drawings, a third object is here depicted as a person  44  sitting on the second side portion of the chair. It is to be observed that in this position the person is located between the transversely extending line  20  and the rear wall  18 . A fourth object, also shown as a person  46 , is positioned proximate the left side of the stage and between the transversely extending line  20  and the rear wall  18 . As illustrated in  FIG. 11 , person  46  will be hidden from the view of the audience when the mirror  28  is advanced to the position shown in  FIG. 11 . 
         [0029]    Also positioned on the stage proximate the central viewing area is a fifth object that here comprises a table  50 . Table  50 , which is of the unique bisected construction best seen in  FIGS. 2 ,  9  and  11 , includes a first portion  50   a  disposed on one side of the transversely extending line  20  and a second portion  50   b  disposed on the opposite side of the transversely extending line. A sixth object, here depicted as a person  52 , is positioned proximate the right-hand portion of the stage in a manner illustrated in  FIG. 2  of the drawings. 
         [0030]    In carrying out one form of the method of the invention for performing the optical illusion, the theatrical stage is first arranged in the manner shown in  FIGS. 1 ,  2  and  3  of the drawings. In this starting configuration, the mirror  28  is hidden from the view of the audience by the superstructure  24  (see particularly  FIG. 2 ). Additionally, the selected first image  26  has been appropriately formed on the rear wall  18  and the second image  32  that corresponds thereto has been formed on surface  30   b  of the scrim, or perforated panel  30 . 
         [0031]    As is well understood by those skilled in the art, the scrim  30 , which is typically constructed from a perforated fabric or the like, appears opaque when front lighted and transparent or translucent when back lighted. Accordingly, in carrying out the method of the invention, when light  34  is illuminated, the scrim will appear opaque to the audience. However, when light  34  and the stage  16  are illuminated, the scrim will appear substantially transparent to the audience and the audience will see the image on the rear wall  18  as well as the various objects on the stage in front of the rear wall. 
         [0032]    Referring to  FIGS. 9 and 11 , when the mirror is advanced to the position there shown, the audience will see the reflection in the mirror of the image  32  on the front scrim and a portion of the table  50  (see the arrows  55 ). However, because the reflected image formed on the scrim is substantially identical to the image  26  formed on the rear wall and because the table is bisected to receive the mirror, the audience will think they are still seeing the image  26  formed on the rear wall  18 . This uniquely creates the illusion that persons  46  and  38  have mysteriously disappeared. 
         [0033]    When the mirror is further advanced along the transversely extending line  20  from the position shown in  FIG. 11  to the advanced position to the position shown in  FIGS. 7 and 8  of the drawings, the audience will see the reflection in the mirror of the front portion  50   a  of the table  50 , the front portion  40   a  of the chair  40  and the complete image  32  formed on the front scrim as reflected by the mirror. Once again, because the reflected image formed on the scrim is substantially identical to the image  26  formed on the rear wall and because both the table and chair are uniquely bisected to receive the mirror in the manner shown in  FIG. 7 , the audience will think they are still seeing the table and chair disposed in front of the image  26  formed on the rear wall  18  (see also  FIGS. 8 ,  9  and  10 ). This uniquely creates the illusion that persons  46 ,  38  and  44  have all mysteriously disappeared, but the table and chair have remained. Person  52 , who is in front of the superstructure  24 , will, of course, remain visible, thereby further enhancing the illusion. 
         [0034]    Having now described the invention in detail in accordance with the requirements of the patent statutes, those skilled in this art will have no difficulty in making changes and modifications in the individual parts or their relative assembly in order to meet specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention, as set forth in the following claims.