Image display apparatus and head-mounted display

Patent metadata

Field	Value
Publication number	US-9229224-B2
Application number	US-201313906866-A
Country	US
Kind code	B2
Filing date	May 31, 2013
Priority date	Jun 4, 2012
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

An image display apparatus includes laser light sources, a light combining section that combines laser light from the laser light sources, and an optical scanner that deflects drawing laser light from the light combining section for two-dimensional scanning. The optical axes of the laser light outputted from the laser light sources and directed toward the optical scanner are present in the same plane. Further, the optical scanner has a light reflection surface configured to be perpendicular to the plane when the optical scanner is not driven. The optical scanner deflects the drawing laser light reflected off the light reflection surface for two-dimensional scanning by causing the light reflection surface to swing within the plane and in the direction perpendicular to the plane.

First claim

What is claimed is:

1. An image display apparatus comprising:
a plurality of light source sections each of which outputs a light;
a light combining section that combines the light from the plurality of light source sections; and
an optical scan section that deflects the combined light from the light combining section for two-dimensional scanning around a first axis and a second axis perpendicular to the first axis,
wherein an optical axis of the light outputted from each of the plurality of light source sections and directed through the light combining section toward the optical scan section is present in a first plane,
the optical scan section includes:
a base that swings around the first axis and the second axis,
a light reflection plate having a light reflection surface that reflects the light from the light combining section, the light reflection surface having an area larger than an area of the base, and
a spacer that connects the base and the light reflection plate to each other,

the first axis is present in the first plane,
the second axis is parallel to a normal of the first plane, and
the light reflection surface is perpendicular to the first plane when the optical scan section is not driven.

2. The image display apparatus according to claim 1 ,
wherein the light reflection surface is irradiated with the combined light traveling in a direction inclined to a normal to the light reflection surface.

3. The image display apparatus according to claim 1 ,
wherein an amplitude of the swing motion of the base around the first axis is greater than an amplitude of the swing motion of the base around the second axis.

4. The image display apparatus according to claim 1 ,
wherein the optical scan section includes:
a frame that surrounds the base,
a support that supports the frame,
a first shaft that connects the base to the frame so that the base is rotatable around the first axis relative to the frame, and
a second shaft that connects the frame to the support so that the frame is rotatable around the second axis relative to the support.

5. The image display apparatus according to claim 4 ,
wherein the light reflection plate is spaced apart from the first shaft in a thickness direction of the light reflection plate but overlaps at least a part of the first shaft when viewed in a thickness direction.

6. The image display apparatus according to claim 4 ,
wherein the first shaft is disposed in parallel to an in-plane direction in the first plane, and
the base resonantly swings around the first axis by resonantly driving a first oscillation system including the light reflection plate, the spacer, the base, and the first shaft.

7. The image display apparatus according to claim 5 ,
wherein a width of the frame in a direction of the normal to the first plane is smaller than a width of the frame in an in-plane direction in the first plane.

8. The image display apparatus according to claim 5 ,
wherein the optical scan section further includes a permanent magnet provided on the frame and a coil that faces the frame and produces a magnetic field that acts on the permanent magnet.

9. The image display apparatus according to claim 1 , further comprising:
a prism on an optical axis of the combined light from the light combining section, the prism inclining the optical axis of the combined light from the light combining section, and changing a cross-sectional shape of the combined light.

10. The image display apparatus according to claim 9 ,
wherein the light from each of the light source sections is linearly polarized light that behaves as s-polarized light with respect to a light incident surface of the prism.

11. The image display apparatus according to claim 9 ,
wherein the prism increases a width of the cross-sectional shape of the combined light in an in-plane direction in the first plane.

12. The image display apparatus according to claim 9 ,
wherein a light exiting surface of the prism is a light collecting lens surface.

13. The image display apparatus according to claim 1 ,
wherein a radiation angle of the light outputted from each of the plurality of light source sections in the direction of the normal to the first plane is greater than a radiation angle of the outputted light in an in-plane direction in the first plane.

14. The image display apparatus according to claim 2 ,
wherein an amplitude of the swing motion of the base around the first axis is greater than an amplitude of the swing motion of the base around the second axis.

15. The image display apparatus according to claim 5 ,
wherein the first shaft is disposed in parallel to an in-plane direction in the first plane, and
the base resonantly swings around the first axis by resonantly driving a first oscillation system including the light reflection plate, the spacer, the base, and the first shaft.

16. The image display apparatus according to claim 6 ,
wherein a width of the frame in the direction of the normal to the first plane is smaller than a width of the frame in the in-plane direction in the first plane.

17. The image display apparatus according to claim 10 ,
wherein the prism increases a width of the cross-sectional shape of the combined light in an in-plane direction in the first plane.

18. The image display apparatus according to claim 10 ,
wherein a light exiting surface of the prism is a light collecting lens surface.

19. The image display apparatus according to claim 11 ,
wherein a light exiting surface of the prism is a light collecting lens surface.

20. A head-mounted display comprising:
a light reflection member that reflects at least part of light incident thereon; and
an image display apparatus that irradiates light to the light reflection member,
the image display apparatus including:
a plurality of light source sections each of which outputs a light,
a light combining section that combines the light from the plurality of light source sections, and
an optical scan section that deflects the combined light from the light combining section for two-dimensional scanning around a first axis and a second axis perpendicular to the first axis,

wherein an optical axis of the light outputted from each of the plurality of light source sections and directed through the light combining section toward the optical scan section is present in a first plane,
the optical scan section includes:
a base that swings around the first axis and the second axis,
a light reflection plate having a light reflection surface that reflects the light from the light combining section, the light reflection surface having an area larger than an area of the base, and
a spacer that connects the base and the light reflection plate to each other,

the first axis is present in the first plane,
the second axis is parallel to a normal of the first plane, and
the light reflection surface is perpendicular to the first plane when the optical scan section is not driven.

21. The image display apparatus according to claim 1 ,
wherein the plurality of light source sections are provided along a predetermined direction, and light emitting directions of the plurality of light source sections are the same.

22. The image display apparatus according to claim 21 , further comprising:
a prism provided on an optical axis of the light combined by the light combining section, wherein
the prism inclines the optical axis of the light combined by the light combining section,

Assignees

• Seiko Epson Corp

Inventors

• Mizoguchi Yasushi
• Ishida Daisuke

Classifications

• G02B5/30 Primary

  Polarising elements (light-modulating devices with active elements G02F1/00) · CPC title

• G02B27/0172

  characterised by optical features · CPC title

• G02B2027/015

  involving arrangement aiming to get less bulky devices · CPC title

• G02B26/101 Primary

  with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129) · CPC title

• G02B26/10

  Scanning systems · CPC title