System for projecting a virtual image within an observer's field of view

• US 20050195491A1
• Filed: 03/03/2005
• Published: 09/08/2005
• Est. Priority Date: 03/04/2004
• Status: Active Grant

• Current Assignee: C.R.F. Societa Consortile Per Azioni
• Original Assignee: C.R.F. Societa Consortile Per Azioni
• Inventors: Repetto, Piermario, Bernard, Stefano, Capello, Davide, Brignone, Mauro, Perlo, Pietro, Pallaro, Nereo, Lambertini, Vito, Pira, Nello Li
• Granted Patent: US 7,318,646 B2
• Time in Patent Office: Days
• US Class Current: 359/649
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 5/7491 of head mounted projectors
• CPC Class Codes: H04N 9/31 Projection devices for colour picture display , e.g. using electronic spatial light modulators [ESLM]

Abstract

A system for projecting a virtual image within an observer'"'"'s field of view comprises a support element, a transparent element mounted on the support element and suitable for being placed in front of the observer'"'"'s eyes, the transparent element comprising a first face and a second face, an image display device suitable for forming an additional image, and a projection and focusing device for projecting the additional image in a manner such as to present it superimposed on the image of the outside world. The display device comprise light-emitting devices disposed on one of the faces of the transparent element, and the projection and focusing device comprise optical elements associated with respective emitting devices and arranged on the other face. Each of the optical elements creates a virtual image of the emitting device associated therewith. The virtual images of the emitting devices together form the additional image.

Claims

1. A system for projecting a virtual image within an observer'"'"'s field of view, comprising:

a support element,

at least one transparent element mounted on the support element and suitable for being placed in front of at least one of the observer'"'"'s eyes in order to transmit an image thereto, the transparent element comprising a first face facing towards the observer and a second face facing towards the outside world,

image display means suitable for forming an additional image, and

projection and focusing means for projecting the additional image in a manner such as to present it superimposed on the image of the outside world, focused at a predetermined distance from the observer,

wherein;

the display means comprise a plurality of light-emitting pixel devices disposed on one of the first and second faces of the transparent element, and

the projection and focusing means comprise a plurality of optical elements associated with respective emitting devices and arranged on the other of the first and second faces of the transparent element in a manner such that each of the optical elements can create a virtual image of the emitting device associated therewith, the virtual images of the individual emitting devices together forming the additional image within the observer'"'"'s field of view.

2. A system according to claim 1 in which the transparent element is a solid element made of transparent glass or plastics material.

3. A system according to claim 1 in which the transparent element is a hollow element formed by a pair of films of transparent material between which a cavity of the element is interposed.

4. A system according to claim 1 in which the transparent element is a solid element made of transparent material to which are applied films or foils of transparent material on which the emitting devices and/or the optical elements are disposed, respectively.

5. A system according to claim 1 in which the optical elements are formed as mirrors so that the face of the transparent element on which the emitting devices are disposed faces towards the observer'"'"'s eye.

6. A system according to claim 1 in which the optical elements are formed as lenses or optical elements which operate by refraction or diffraction, so that the face of the substrate on which the emitting devices are disposed faces towards the portion of the outside world which extends in front of the observer, with respect to his direction of observation.

7. A system according to claim 1 in which each emitting device and the optical elements associated therewith are disposed at opposite ends of tube-like portions of the transparent element, the tube-like portions having opaque side walls.

8. A system according to claim 1 in which the transparent element is flat, the emitting devices and the optical elements being arranged and oriented in a manner such that the optical axis of each system formed by an emitting device and by the respective optical element is oriented towards the observer'"'"'s eye.

9. A system according to any one of claims 1 in which the transparent element is curved so that the optical axis of each system formed by an emitting device and by the respective optical element is oriented towards the observer'"'"'s eye.

10. A system according to any one of claims 1 in which the optical elements comprise a prismatic component so as to project the virtual image of the respective emitting devices in predetermined positions within the observer'"'"'s field of view.

11. A system according to claim 1 in which the emitting devices and the optical elements associated therewith are disposed in a matrix-like arrangement on the respective faces of the transparent element, and are distributed in a non-uniform manner, according to their position relative to the observer'"'"'s field of view.

12. A system according to claim 1 in which the emitting devices are of an organic type, such as an OLED or a PLED, or of an inorganic type, such as a microLED, a quantum dot laser, a nanostructured metallic source, a carbon nanotube source, a metal or polymer nanowire source, or a field emission source.

13. A display device wearable by a user, comprising a projection system according to claim 1, comprising a control unit for controlling the emitting devices, connected to the emitting devices by means of a pattern of electrical connections arranged on the face of the transparent element on which the emitting devices are disposed.

14. A device according to claim 13 in which the curvature of the lens and the projection system as a whole are optimized jointly for the focusing of the image.