Stereoscopic image pickup system

• US 6,862,140 B2
• Filed: 01/30/2001
• Issued: 03/01/2005
• Est. Priority Date: 02/01/2000
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ogino, Shigeru
• Primary Examiner(s): Chang, Audrey
• Assistant Examiner(s): Allen, Denise S.
• Application Number:
  US09/772,002
• Publication Number:
  US 20010019450A1
• Time in Patent Office: 1,491 Days
• Field of Search: 359/462, 359/473, 359/407, 359/411, 359/412, 396/331, 348/49, 348/343, 369/112.02
• US Class Current: 359/473
• CPC Class Codes: H04N 13/211 using temporal multiplexing
• CPC Class Codes: H04N 13/257 Colour aspects
• CPC Class Codes: H04N 13/296 Synchronisation thereof; Control thereof
• CPC Class Codes: H04N 2013/0081 Depth or disparity estimation from stereoscopic image signals

Abstract

A stereoscopic image pickup system for obtaining parallactic images includes a pair of front optical components, the pair of front optical components respectively including a pair of reflecting members capable of rotating around respective predetermined axes and having a reflecting function, and a pair of amount-of-light control members arranged to respectively vary amounts of transmission of light fluxes coming from the pair of reflecting members alternately in a time-series manner, an optical member arranged to superpose respective optical axes of the pair of front optical components on each other, a rear optical component having an optical axis coinciding with the superposed optical axes of the pair of front optical components and having a magnification varying function, and a controller for controlling an amount of parallax of parallactic images by using the pair of reflecting members in accordance with a magnification varying operation of the rear optical component.

Claims

1. A stereoscopic image pickup system for obtaining parallactic images, said stereoscopic image pickup system comprising:

a pair of front optical components, said pair of front optical components respectively including (a) a pair of reflecting members, each reflecting member rotating around a respective predetermined axis at a first speed, and (b) a pair of amount-of-light control members arranged to respectively vary amounts of transmission of light fluxes traveling from said pair of reflecting members alternately in a time-series manner;

a combining optical member arranged to superpose optical axes of said pair of front optical components;

a rear optical component, said rear component including a zooming optical member, the zooming optical member moving on an optical axis superposed by said combining optical member at a second speed so as to vary an image magnification; and

a controller for calculating the first speed of each one of the pair of reflecting members in accordance with the second speed of the zooming optical member, so that an amount of parallax of parallactic images is within a predetermined range,

wherein said pair of amount-of-light control members are positioned between said pair of reflecting members and said optical member, respectively, along the optical axes.

2. A stereoscopic image pickup system according to claim 1, wherein said controller controls the amount of parallax of parallactic images by varying a convergence distance, which is a distance from a point of intersection between a light flux and each of said pair of reflecting members to a point of intersection between the optical axis of said rear optical component and an optical axis of each of said pair of reflecting members.

3. A stereoscopic image pickup system according to claim 2, further comprising:

a distance detector for detecting distance information of an object; and

a focal length detector for detecting a focal length of said rear optical component,

wherein said controller controls the amount of parallax by using the distance information detected by said distance detector, the convergence distance found on the basis of rotational angle information of said pair of reflecting members, and the focal length detected by said focal length detector.

4. A stereoscopic image pickup system according to claim 1, wherein said controller controls the amount of parallax of parallactic images in such a manner that, during a magnification varying operation of said rear optical component, the amount of parallax for an object becomes approximately equal to an amount of parallax obtained at the time of start of the magnification varying operation.

5. A stereoscopic image pickup system according to claim 1, wherein said controller controls the amount of parallax of parallactic images in such a manner that the sign of a difference value of amounts of parallax for an object during a magnification varying operation of said rear optical component is positive or negative.

6. A stereoscopic image pickup system according to claim 1, wherein said controller causes said pair of reflecting members not to rotate during a magnification varying operation of said rear optical component.

7. A stereoscopic image pickup system according to claim 1, wherein said pair of amount-of-light control members respectively change transmission and non-transmission of light fluxes coming from said pair of reflecting members alternately in a time-series manner.

8. A stereoscopic image pickup system according to claim 1, wherein each of said pair of amount-of-light control members is a liquid crystal shutter.

9. A stereoscopic image pickup system according to claim 1, further comprising a storage device connected to said controller and arranged to store therein the predetermined range of amounts of parallax for every object distance.

10. A stereoscopic image pickup system according to claim 1, wherein said stereoscopic image pickup system is a lens unit capable of being detachably attached to a camera unit having an image sensor.

11. A stereoscopic image pickup system according to claim 10, wherein said controller sends and receives information to and from a controller provided in the camera unit.

12. A stereoscopic image pickup system according to claim 1, further comprising an image sensor for converting light incident on said stereoscopic image pickup system into an electrical signal.

13. A stereoscopic image pickup system according to claim 12, wherein said controller includes a first controller provided in a lens side included in said stereoscopic image pickup system, and a second controller provided in a camera side included in said stereoscopic image pickup system, and wherein sending and receiving of information being performed between said first controller and said second controller.

14. A stereoscopic image pickup system according to claim 1, wherein said controller comprises a microcomputer.

15. A stereoscopic image pickup system according to claim 1, wherein the amount of parallax P of parallactic images at an initial stage satisfies the following equation:

$P=\frac{2·<br><br>S·<br><br>f·<br><br>I·<br><br>\left(H-F\right)}{C·<br><br>\left(I^2+F·<br><br>H\right)}$

wherein H is the object distance, F is the convergence distance, f is the focal length, I is half of the mirror interval, S is the width of a display screen, and C is the length of a longer side of a CCD.