Image display apparatus

Patent metadata

Field	Value
Publication number	US-12025810-B2
Application number	US-201915733984-A
Country	US
Kind code	B2
Filing date	May 29, 2019
Priority date	Jun 8, 2018
Publication date	Jul 2, 2024
Grant date	Jul 2, 2024

Abstract

An image display apparatus ( 1 C) of the present disclosure includes: an image light formation section ( 30 ) that outputs image light; a diffractive optical system that includes a first diffractive section ( 11 ) including at least one diffractive device and a second diffractive section ( 12 ) causing the image light to converge at a pupil position of a viewer, the first diffractive section ( 11 ) having a property of correcting a chromatic aberration that occurs at the second diffractive section ( 12 ); and a relay optical system ( 20 ) disposed closer to the image light formation section ( 30 ) than the second diffractive section ( 12 ) and relaying the image light to the second diffractive section ( 12 ) to correct the chromatic aberration that occurs at the second diffractive section ( 12 ).

First claim

The invention claimed is:

1. An image display apparatus comprising:
an image light formation section that outputs image light;
a diffractive optical system that includes a first diffractive section including at least one diffractive device and a second diffractive section causing the image light to converge at a pupil position of a viewer, the first diffractive section having a property of correcting a chromatic aberration that occurs at the second diffractive section;
a relay optical system disposed closer to the image light formation section than to the second diffractive section, and relaying the image light to the second diffractive section to correct the chromatic aberration that occurs at the second diffractive section; and
a light guide plate that guides the image light outputted from the relay optical system to the second diffractive section, wherein
the light guide plate has a first surface and a second surface opposed to each other, and
the second diffractive section is disposed on the first surface, the second surface, or both, of the light guide plate.

2. The image display apparatus according to claim 1 , wherein the first diffractive section has a property of causing a chromatic aberration to occur on at least part of light that enters the second diffractive section, the chromatic aberration being optically symmetrical to that occurring at the second diffractive section.

3. The image display apparatus according to claim 1 , wherein the image light formation section includes a plurality of optical devices, and one or more but not all of the plurality of optical devices are disposed between the first diffractive section and the second diffractive section.

4. The image display apparatus according to claim 3 , wherein the image light formation section includes, as the plurality of optical devices, a scanning optical device that forms the image light, the scanning optical device being disposed between the first diffractive section and the second diffractive section.

5. The image display apparatus according to claim 1 , wherein the image light formation section is entirely disposed farther than the first diffractive section and the second diffractive section as viewed from the viewer.

6. The image display apparatus according to claim 1 , wherein the image light formation section includes a corrective optical device that corrects astigmatism occurring at the second diffractive section.

7. The image display apparatus according to claim 1 , wherein the first diffractive section and the second diffractive section each have a structure in which a plurality of diffraction patterns are layered, a structure in which a plurality of diffraction patterns are multiplexed, or a structure in which the layered structure and the multiplexed structure are combined with each other to allow a plurality of pieces of the image light that are different in wavelength band from each other to converge toward the pupil position of the viewer.

8. The image display apparatus according to claim 1 , further comprising:
a detector that detects the pupil position of the viewer; and
a controller that causes, on a basis of a result of detection by the detector, the second diffractive section to move in at least one moving direction corresponding to a horizontal direction of a field of view of the viewer, a vertical direction of the field of view of the viewer, or a depth direction of an eyeball of the viewer, and thereby causes a convergence position of the image light to move to the pupil position of the viewer.

9. The image display apparatus according to claim 1 , further comprising:
a detector that detects the pupil position of the viewer; and
a controller that causes, on a basis of a result of detection by the detector, the image light formation section to move in at least one moving direction corresponding to a horizontal direction of a field of view of the viewer, a vertical direction of the field of view of the viewer, or a depth direction of an eyeball of the viewer, and thereby causes a convergence position of the image light to move to the pupil position of the viewer.

10. The image display apparatus according to claim 1 , wherein the image light formation section includes
a light source, and
a scanning optical device that forms the image light by scanning a flux of light emitted from the light source.

11. The image display apparatus according to claim 1 , further comprising a movable reflective device that allows a disposition angle thereof to be changed to enable movement of a convergence position of the image light.

12. The image display apparatus according to claim 11 , further comprising:
a detector that detects the pupil position of the viewer; and
a controller that changes, on a basis of a result of detection by the detector, the disposition angle of the movable reflective device, and thereby causes the convergence position of the image light to move to the pupil position of the viewer.

13. The image display apparatus according to claim 11 , wherein the movable reflective device is disposed on an optical path of the image light outputted from the image light formation section.

14. The image display apparatus according to claim 13 , wherein the movable reflective device is disposed between the image light formation section and the second diffractive section.

15. An image display apparatus comprising:
an image light formation section that outputs image light;
a diffractive optical system that includes a first diffractive section including at least one diffractive device and a second diffractive section causing the image light to converge at a pupil position of a viewer, the first diffractive section having a property of correcting a chromatic aberration that occurs at the second diffractive section; and
a relay optical system disposed closer to the image light formation section than to the second diffractive section and relaying the image light to the second diffractive section to correct the chromatic aberration that occurs at the second diffractive section,
wherein the first diffractive section includes
a first diffractive device having the property of correcting the chromatic aberration that occurs at the second diffractive section, and
a second diffractive device disposed on an optical path between the first diffractive device and the second diffractive section and causing the image light outputted from the first diffractive device to converge.

16. The image display apparatus according to claim 15 , wherein the second diffractive device constitutes a portion of the relay optical system.

17. The image display apparatus according to claim 15 , wherein
the first diffractive device is a transmissive diffractive device, and
the second diffractive device is a transmissive or reflective diffractive device.

18. The image display apparatus according to claim 15 , wherein
the first diffractive device is a reflective diffractive device, and
the second diffractive device is a transmissive or reflective diffractive device.

19. The image display apparatus according to claim 1 , further comprising a prism.

20. The image display apparatus according to claim 1 , wherein
the second diffractive section is disposed on the first surface of the light guide plate, and
the prism is disposed on the second surface of the light guide plate.

Assignees

• Sony Corp

Inventors

• Yoshikaie Akira
• Ueda Daisuke

Classifications

• G02C2202/22

  Correction of higher order and chromatic aberrations, wave front measurement and calculation · CPC title

• G02C7/083

  Electrooptic lenses · CPC title

• G02B2027/0187

  slaved to motion of at least a part of the body of the user, e.g. head, eye · CPC title

• G02B2027/0116

  comprising devices for correcting chromatic aberration · CPC title

• G02B27/0172 Primary

  characterised by optical features · CPC title