IMAGEING ELEMENT AND DISPLAY

• US 20100231860A1
• Filed: 03/22/2007
• Published: 09/16/2010
• Est. Priority Date: 03/23/2006
• 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 8,057,043 B2
• Time in Patent Office: Days
• US Class Current: 353/10
• CPC Class Codes: G02B 30/56 by projecting aerial or floating images
• CPC Class Codes: G02B 5/08 Mirrors vehicle mirrors involving special optical features B60R1/08
• CPC Class Codes: G02B 5/136 plural reflecting elements forming part of a unitary body G02B5/124 takes precedence
• CPC Class Codes: H04N 13/388 Volumetric displays, i.e. systems where the image is built up from picture elements distributed through a volume

Abstract

As optical elements for bending a light beam when it passes through an element face constituting one plane, a plurality of unit optical elements for reflecting light on one or more mirror surfaces arranged perpendicularly or at an angle nearly perpendicular to the element face are disposed to constitute an optical imaging element. Light emitted from projection object disposed on one side of the element face is reflected on the mirror surface when it passes through the element face so that a real image is formed in a space on the other side of the element face where a physical entity does not exist, thus constituting a display equipped with the optical imaging element. An aerial picture projection system not existing heretofore is also provided.

Claims

1. An optical imaging element comprising:

an optical element for causing a light ray to bend as light passes through an element surface, which is one planar surface, and

an arrangement of a plurality of unit optical elements for reflecting light by at least one specular surface arranged at an angle perpendicular, or nearly perpendicular, to the element surface.

2. The optical imaging element according to claim 1, wherein the unit optical element comprises two non-parallel specular surfaces.

3. The optical imaging element according to claim 2, wherein the plurality of unit optical elements has functionally similar configurations and is arranged to point in a plurality of directions within the element surface.

4. The optical imaging element according to claim 2, wherein the unit optical element functions as a dihedral corner reflector including two orthogonal specular surfaces.

5. The optical imaging element according to claim 4, wherein the dihedral corner reflectors are arranged to point in a plurality of directions within an element surface.

6. The optical imaging element according to claim 4, wherein the dihedral corner reflectors are arranged to point in a similar direction within an element surface.

7. The optical imaging element according to claim 1, wherein an interior wall of an optical hole, assumed to lie in a direction to pass completely through the element surface, is used as the specular surface of the unit optical element.

8. The optical imaging element according to claim 7, wherein the optical holes of the unit optical element are linked together with mutual dependence.

9. The optical imaging element according to claim 7,

further comprising a substrate for partitioning a predetermined space, wherein

one planar surface passing through the substrate is specified as the element surface, and

an interior wall of a hole made in the substrate as the optical hole, assumed to lie in a direction to pass completely through the element surface, is used as the specular surface of the unit optical element.

10. The optical imaging element according to claim 9, wherein the unit optical element comprises a hole made in a substrate and filled with a transparent gas or liquid.

11. The optical imaging element according to claim 7, wherein a tubular body, comprising a transparent solid body, is used as an optical hole of the unit optical element, assumed to lie in a direction to pass completely through the element surface.

12. The optical imaging element according to claim 11, wherein the tubular bodies of the unit optical element are mutually adhered to each other.

13. The optical imaging element according to claim 7, wherein the optical hole comprises a cubic or rectangular parallelepiped shape.

14. The optical imaging element according to claim 13, wherein all of four surfaces of interior walls of the optical hole are specular surfaces.

15. The optical imaging element according to claim 7, wherein

two mutually orthogonal specular surfaces are formed on interior walls of the optical hole, and

a surface of the interior walls other than the two orthogonal specular surfaces is formed non-perpendicularly to the element surface.

16. The optical imaging element according to claim 7, wherein

two mutually orthogonal specular surfaces are formed on interior walls of the optical hole, and

a surface of the interior walls other than the two orthogonal specular surfaces is a non-specular surface.

17. The optical imaging element according to claim 1, wherein the plurality of unit optical elements is arranged in a regular grid shape within the element surface.

18. The optical imaging element according to claim 1, wherein a specular surface of the unit optical element uses a reflection by a flat surface made of a glossy substance.

19. The optical imaging element according to claim 1, wherein a specular surface of the unit optical element uses a reflection or a total internal reflection by a flat interface between transparent media having different refractive indices.

20. The optical imaging element according to claim 1, wherein a specular surface of the unit optical element comprises a plurality of unit specular surfaces arranged in a parallel fashion.

21. A display device comprising

a main unit including the optical imaging element according to claim 1 and

an object arranged on an underside of the main unit, wherein

light emitted by the object is transmitted through the optical imaging element, thereby forming and projecting a real image of the object in a space on an upper side of the main unit.

22. The display device according to claim 21, wherein the object comprises a three dimensional actual object or a three dimensional image displayed by a device for displaying images, and a depth thereof in a direction for viewing the real image is inverted in advance.

23. The display device according to claim 21, wherein

the object comprises an actual object having a movement incurred automatically or by an external force, and

the display device projects a moving floating image, as a real image of the actual object, in a space on an upper side of the main unit.