Optical-illusion device

[57] ABSTRACT

A device for creating optical illusions comprising a transparent sheet, a plurality of fresnel screens spaced apart and in a regular array on the sheet, a condensing lens formed by each of the fresnel screens and a reflecting surface juxtaposed with the sheet.

Claim, 13 Drawing Figures

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PATENTED MAY 91972

3,661,385

SHEET 1 OF 4

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BY _rl

Attorney

PATENTED may 919?z

3,661,385

SHEET 2 OF 4

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FIG. 2

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PATENTED may 9 isze

3,661,385

SHEET 3 OF 4

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PATENTED MAY 9 1972

3,66.1,385

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Henry Schneider

INVENTOR.

BY

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Attorney

3,661,385

OPTICAL-ILLUSION DEVICE

The present invention relates, in general, to optical-illusion devices and, more particularly, to optical-illusion devices employing light-condensing and light-reflecting means, both moving and stationary.

Heretofore, illusion devices of the above-mentioned type consisted mainly of kaleidoscopes, using a system of angled mirrors and multi-colored, translucent inserts and image-projection devices.

It is, therefore, an object of the invention to provide an optical illusion device for creating a plurality of stationary, upright images.

Another object of the invention is to provide an optical illusion device for creating a plurality of orbiting, up-right images.

The above-mentioned objects and others, which will become apparent hereinafter, are achieved by forming, on a transparent sheet, a plurality of fresnel screens, preferably comprised of concentric grooves, centered on the geometric center that the particular screen outline defines.

The fresnel screens, which act, in the system of the invention, as condensing lenses, are arranged in an array across the transparent sheet, which is juxtaposed with a reflecting surface, such as a mirror. The array may comprise orthogonal rows of spaced condensing lenses.

According to a more specific feature of the invention, the transparent sheet and mirror are adjacent and closely juxtaposed, and are held in a common frame, which is manually movable or is provided with a motor for rotating the sheet.

A viewer, juxtaposed with the sheet and mirror arrangement, will see his reduced, up-right image formed on each of the screens, after his image has passed through, and been reduced by, the condensing fresnel screens and reflected back from the mirror to the screens. A conventional lens (without the fresnel screen) will merely pass light in either direction and display images at its surface.

If the transparent sheet is rotated, the viewer will see his upright images orbiting about a central point.

The above and other objects, features and advantages of the invention will become more readily apparent from the following description, reference being made to the accompanying drawing, in which:

FIG. 1 is a perspective view of a device according to the invention; 45

FIG. 1A is a section taken along line IA in FIG. 1;

FIGS. 2 and 3 are plan views of FIG. 1 in different positions;

FIG. 4 is a sectional view of another embodiment of the invention;

FIG. 5 is a sectional view of still another embodiment of the 50 invention;

FIG. 6 is a perspective view of a further embodiment of the invention;

FIG. 7 is another perspective view of yet a further embodiment of the invention; and 55

FIG. 8 is a plan view of yet another embodiment of the invention;

FIGS. 9-12 are sectional views of different embodiments according to the invention.

The embodiment of the optical illusion device 10, shown in 60 the drawing of FIG. 1, has a rectangular, transparent sheet 1, made of a synthetic resin having a series of fresnel screens 2 formed in the surface 1'.

The screens 2 have a rectangular outline and are arranged in vertical and horizontal rows which are spaced apart, leaving 65 clear strips 3 surrounding the screens 2.

As can best be seen in FIG. 1A, the fresnel screens 2, which act as condensing lenses, are formed in the surface 1' of sheet 1 by pressing or stamping with a heated die.

The screens 2 are comprised by concentric circular grooves 70 2' separated by ridges 2, the grooves 2' being somewhat wider than the ridges 2, the grooves 2' and ridges 2 being concentric with the axis “O” of the screen 2.

The sheet 1 is adjacent a reflecting surface, such as a mirror 4, the sheet 1 and the mirror 4 being held in place by a frame 5 75 which surrounds them, the frame 5 having a groove 5' into which the sheet 1 is fitted and a further groove S into which the mirror 4 is fitted, the sheet 1 and the mirror 4 being held in a fixed, spaced-apart relationship by the grooves S' and 5.

In operation, an object, such as the pencil 6, is held in front of the sheet 1. The light reflected from the pencil 6 passed through the clear strips 3 surrounding the screens 2, forming an image 6' on the mirror 4, as can best be seen in FIG. 2, which is reflected back through the clear strips 3, to an observer juxtaposed with the device 10, beyond the pencil 6. The light reflected from pencil 6 also passes through the screens 2, where the light from the pencil 6 is condensed and passes on to the mirror 4 where a reduced image 6 of the pencil 6 is formed and reflected back through the screens 2, where the reflected light is further condensed, the twice reduced image 6 appearing on the fresnel screens 2 which, in addition to acting as a condensing lens, provides a surface on which an image can be formed.

The images 6 formed on the screens 2 are upright and remain so when the device 10 is rotated, as seen in FIG. 3, giving an illusion of a multitude of independently rotating images 6, revolving about a central image 6'.

In FIG. 6, an optical device 11, specifically designed for rotating, comprises a circular transparent sheet 41 having an array of circular condensing fresnel screens 42, formed in the surface 41'.

The sheet 41 is rotatably held by a frame 45, adjacent to a mirror 44, the sheet 41 being driven by a motor 12 and a toothed wheel 13, engageable with teeth 14 provided along the periphery 15 of sheet 41.

The embodiments shown in FIG. 4 and 5 are similar to that of FIG. 1 except for the mirror 24, which is convex in one plane and the mirror 34, which is concave in one plane. If either or these embodiments is rotated as a unit, the images formed will appear to pulsate as the plane of distortion rotates, in addition to the other illusions earlier mentioned.

In FIG. 7 the sheet 1 forms one wall of an infinity box 50, having pairs of parallel walls 52, 52' and 53, 53', the pairs set at right angles to one another, and an end wall 51, perpendicular to the walls 52, 52', 53, 53' and parallel with the sheet 1. The walls 51, 52, 52', 53, 53' are internally reflective within the box 50, so that any images formed on the screens 2 will be reflected from the mirrored surfaces back and forth, giving a viewer looking through the sheet 1 an illusion of an infinite number of repeating images.

The rotating spheres 100, shown in FIG. 8, comprise an outer transparent sphere 101 having an array of condensing fresnel screens 102 formed about the surface. An inner sphere 104, having a mirrored surface, is concentrically supported within the sphere 101 by a shaft 113, connected to a drive motor 112.

When the spheres are rotated by the motor 112, an illusion of images moving toward and away from a viewer is created.

In the embodiment shown in FIG. 9, the illusion device 20 has a triangular configuration with the legs of the triangle comprised by the mirrors 4 and 4' and the base by the transparent lens sheet 1, through which the illusion is viewed.

The device 30 illustrated in FIG. 10 is another triangle arrangement in which the legs of the triangle are comprised by the lens sheet 1 and the mirror 4 and the base by a clear, transparent sheet 31. The illusion created by the device 30 can be viewed through either the clear side 31 or the lens sheet 1.

FIG. 11 shows an illusion device 60 having a rectangular configuration with the mirror 4 arranged parallel with the lens sheet 1 and spaced from it by the clear sheets 31.

In FIG. 12, the device 70 comprises the flat mirror 4 with a pair of stacked lens sheets 1 abutting the reflective surface of the mirror 4.

To create still further illusions, the clear areas 3 which surround the screens 2 can be masked and the screens provided in colors which are the same or different from each other.