VOLUME SCANNING THREE-DIMENSIONAL FLOATING IMAGE DISPLAY DEVICE

• US 20100214394A1
• Filed: 09/19/2008
• Published: 08/26/2010
• Est. Priority Date: 09/21/2007
• Status: Active Grant

• Current Assignee: National Institute of Information and Communications Technology
• Original Assignee: National Institute of Information and Communications Technology
• Inventors: Maekawa, Satoshi
• Granted Patent: US 8,730,308 B2
• Time in Patent Office: Days
• US Class Current: 348/51
• CPC Class Codes: G02B 30/56 by projecting aerial or floating images
• CPC Class Codes: G02B 5/136 plural reflecting elements forming part of a unitary body G02B5/124 takes precedence

Abstract

A volume scanning three-dimensional floating image display is constructed from a real mirror image forming optical system capable of forming the real mirror image of an object to be projected in a planar symmetric position with respect to a symmetry surface, and a display located under the symmetry surface showing images that serve as the object to be projected, and an actuator means capable of moving the display in a direction with a component perpendicular to the display surface, so by changing the displayed image synchronously with the motion of the display, the real mirror image of that image will be formed in the space on the other side of the symmetry surface as a three-dimensional floating image.

Claims

1. A volume scanning three-dimensional floating image display device, comprising:

a real mirror image forming optical system, capable of forming the real mirror image of an object to be projected in a planar symmetric position with respect to a geometrical plane, said plane becoming a symmetry surface, and

a display located under said symmetry surface and comprising a display surface for showing images as said object to be projected, and

an actuator means that can move said display in a path containing a component perpendicular to said display surface;

wherein by changing the images shown in said display surface in synchronicity with the movement of said display due to said actuator means, a three-dimensional floating image of said images will be formed in the space above said symmetry surface.

2. A volume scanning three-dimensional floating image display according to claim 1 wherein said real mirror image forming optical system is a dihedral corner reflector array comprising a plurality of dihedral corner reflectors, said dihedral corner reflectors comprising of two mutually perpendicular specular surfaces arranged perpendicularly to an optical device plane, whereas said optical device plane becomes said symmetry surface.

3. A volume scanning three-dimensional floating image display according to claim 2, wherein a plurality of said dihedral corner reflectors are arranged while being rotated in a plurality of directions around a common axis of rotation that is perpendicular to the said optical device plane, whereby said three-dimensional image will be formed in the space above said optical device plane in a manner to be observable from multiple observing points in said space.

4. A volume scanning three-dimensional floating image display according to claim 1 wherein said real mirror image forming optical system is comprised of a retroreflector array capable of recursively reflecting light, and a half-mirror capable of reflecting and transmitting light, whereas with the surface of said half-mirror becoming said symmetry surface, said retroreflector array is located in the space on the same side of said half-mirror like said object to be projected.

5. A volume scanning three-dimensional floating image display according to claim 4 wherein said retroreflector array is arranged in the space on the back side of said half-mirror in a manner to at least enclose together with said half-mirror the display surface of said display in a three-dimensional way.

6. A volume scanning three-dimensional floating image display according to claim 1 wherein said real mirror image forming optical system is comprised of an afocal lens array comprising of a plurality of afocal lenses arranged along an optical device plane with their optical axis perpendicular to said optical device plane, whereby said optical device plane becomes said symmetry surface.

7. A volume scanning three-dimensional floating image display according to claim 1, wherein said display comprises of display surfaces on both of its front and back sides.

8. A volume scanning three-dimensional floating image display according to claim 1, wherein said display is located with its display surface facing said symmetry surface, and said actuator means is made capable of moving said display in a path containing a component perpendicular to said symmetry surface.