Imaging apparatus for taking images of objects in a plurality of directions and vehicle incorporating the same

• US 8,115,161 B2
• Filed: 02/24/2009
• Issued: 02/14/2012
• Est. Priority Date: 02/26/2008
• Status: Expired due to Fees

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Imaging Corporation (Olympus Corporation)
• Inventors: Takahashi, Koichi
• Primary Examiner(s): Legasse, Jr., Francis M
• Application Number:
  US12/380,234
• Publication Number:
  US 20090212202A1
• Time in Patent Office: 1,085 Days
• Field of Search: 250/208.1, 250/216, 250/214.1, 250/214.R, 348/369, 348/42, 348/49, 348/51, 348/148, 348/333.08, 348/333.09, 348/333.1, 348/341, 359629-638
• US Class Current: 250/216
• CPC Class Codes: B60R 11/04 Mounting of cameras operative during drive; Arrangement of controls thereof relative to the vehicle
• CPC Class Codes: B60R 2001/1253 with cameras, video cameras or video screens
• CPC Class Codes: G02B 5/04 Prisms
• CPC Class Codes: G03B 17/00 Details of cameras or camera bodies; Accessories therefor lens hoods or caps G03B11/04
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/58 Means for changing the camera field of view without moving the camera body, e.g. nutating or panning of optics or image sensors

Abstract

The invention relates to an imaging apparatus that is capable of taking images of objects in at least three directions on a single imaging device, has a wide imaging angle of view and can easily be made compact, and a vehicle incorporating it. The imaging apparatus comprises a single imaging device 30 and at least three imaging optical systems 101, 102 and 103 that are located in juxtaposition to form on an imaging plane of the imaging device 30 at least three images in varying imaging directions. Of the three imaging optical systems 101, 102 and 103, at least two 101 and 102 reflect axial chief rays from objects in the right-and-left direction intersecting the direction of juxtaposition, and each have a curved reflecting surface of concave shape.

Claims

1. An imaging apparatus adapted to take images of objects in a plurality of directions, comprising:

a single imaging device, and

at least three imaging optical systems located in juxtaposition to form at least three images on an imaging plane of said single imaging device in different imaging directions, wherein;

of said at least three imaging optical systems, at least two each comprise a curved reflecting surface of concave shape that reflects light rays from objects in a right-and-left direction intersecting a direction of juxtaposition of said juxtaposed optical systems;

said at least three imaging optical systems include a first imaging optical system, a second imaging optical system and a third imaging optical system; and

the first imaging optical system, the second imaging optical system and the third imaging optical system are positioned such that;

a first axial chief ray exiting out from the first imaging optical system arrives at the imaging device not via the second imaging optical system and the third imaging optical system,

a second axial chief ray exiting out from the second imaging optical system arrives at the imaging device not via the first imaging optical system and the third imaging optical system, and

a third axial chief ray exiting out from the third imaging optical system arrives at the imaging device not via the first imaging optical system and the second imaging system.

2. The imaging apparatus according to claim 1, wherein said curved reflecting surfaces of concave shape in said at least two imaging optical systems are each in an irrotational symmetric, aspheric shape.

3. The imaging apparatus according to claim 1, wherein said at least two imaging optical systems each have a plurality of reflecting surfaces.

4. The imaging apparatus according to claim 1, wherein said at least two imaging optical systems each have a plurality of curved reflecting surfaces.

5. The imaging apparatus according to claim 4, wherein said plurality of curved reflecting surfaces in said two imaging optical systems are each in an irrotational symmetric, aspheric shape.

6. The imaging apparatus according to claim 3, wherein said at least two imaging optical systems each have a prism having said plurality of reflecting surfaces.

7. The imaging apparatus according to claim 6, wherein said prisms in said at least two imaging optical systems each comprise, in order from an object side along an axial chief ray toward an image plane,

a first surface having transmitting action,

a second surface having internal reflecting plus transmitting action, and

a third reflecting surface having reflecting action;

said prisms are each formed of a medium having a refractive index of 1.45 or greater; and

said axial chief ray enters the medium through said first surface, is reflected off said second surface, then off said third surface, and then leaves the medium through said second surface.

8. The imaging apparatus according to claim 7, wherein said at least two imaging optical systems each comprise an aperture stop located on an object side of said first surface of said prism.

9. The imaging apparatus according to claim 1, wherein the reflecting surfaces in said at least two imaging optical systems are tilted with respect to the axial chief ray such that a plane including the axial chief ray is vertical to the direction of juxtaposition of said at least three imaging optical systems.

10. The imaging apparatus according to claim 1, wherein said at least two imaging optical systems are of the same shape, and one imaging optical system is flipped with respect to another with an axis vertical to the imaging plane of the imaging device as an axis of symmetry.

11. The imaging apparatus according to claim 1, wherein of said at least three imaging optical systems, at least one is adapted to reflect an axial chief ray from an object in a direction between imaging directions of said at least two imaging optical systems, and said at least one imaging optical system comprises a curved reflecting surface of concave shape.

12. The imaging apparatus according to claim 1, wherein said at least one imaging optical system is adapted to take an image of an object in a direction vertical to said imaging plane.

13. The imaging apparatus according to claim 11, wherein said at least one imaging optical system comprises a prism that is located in front of the imaging plane and has said curved reflecting surface;

said prism in said at least one imaging optical system is located in the same orientation as any one of said at least two imaging optical systems is located; and

said at least one imaging optical system comprises a reflecting surface that is located on an object side with respect to said prism and reflects light rays.

14. The imaging apparatus according to claim 13, wherein said at least one imaging optical system comprises a prism that is located in front of the imaging plane and has said curved reflecting surface;

said prism in said at least one imaging optical system is located in the same orientation as any one of said at least two imaging optical systems is located;

said at least one imaging optical system comprises a reflecting member that is located on an object side with respect to said prism and reflects light rays;

said reflecting member comprises a fourth surface having transmitting and internal reflecting action, a fifth surface having reflecting action, and a sixth surface having transmitting action; and

said axial chief ray enters the medium through said fourth surface, is reflected off said fifth surface, then off said fourth surface, and then leaves the medium through said sixth surface.

15. The imaging apparatus according to claim 13, wherein said prisms in said at least one imaging optical system comprises, in order from an object side along an axial chief ray toward an image plane,

a first surface having transmitting action,

a second surface having internal reflecting plus transmitting action, and

a third reflecting surface having reflecting action;

said prism in said at least one imaging optical system is formed of a medium having a refractive index of 1.45 or greater; and

said axial chief ray enters the medium through said first surface, is reflected off said second surface, then off said third surface, and then leaves the medium through said second surface.

16. The imaging apparatus according to claim 13, wherein there is an additional imaging optical system located in a different orientation between said at least one imaging optical system and an imaging optical system located in the same orientation as it is located.

17. The imaging apparatus according to claim 12, wherein an imaging field of view set by said at least two imaging optical systems is linked to an imaging field of view of said at least one imaging optical system.

18. The imaging apparatus according to claim 11, wherein said at least one imaging optical system is adapted to form an image of an object in a direction that is tilted in the direction of juxtaposition of said at least three imaging optical systems with respect to a direction vertical to said imaging plane.

19. The imaging apparatus according to claim 18, wherein said at least three imaging optical systems are all identical, and wherein said at least one imaging optical system is located in a different orientation from orientations of said at least two imaging optical systems.

20. The imaging apparatus according to claim 1, wherein said at least three imaging optical systems are provided with a light block member inserted between them that blocks off light rays from the adjacent imaging optical system or systems.

21. A vehicle, comprising:

a vehicle body, and

an imaging apparatus as recited in claim 1, which is attached to a front portion of said body.

22. A vehicle, comprising:

a vehicle body, and

an imaging apparatus as recited in claim 1, which is attached to said body.