JP2001305681A - Stereocamera device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereocamera device by which an excellent distance resolving function is achieved for a base length. SOLUTION: The image formation ranges S1 and S2 of optical systems 21 and 22 are both set wider than the image pickup range W of imaging devices 41 and 42. Imaging device bases 31 and 32 on which the imaging devices 41 and 42 are respectively mounted are moved in parallel in a base line direction. Also, it is provided with a mechanism to equalize the moving amounts of the imaging device bases 31 and 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereo camera device, and more particularly to a technique for improving the distance resolution of a stereo camera device.

[0002]

2. Description of the Related Art There is known a stereo camera device capable of detecting the presence or absence of an object or measuring the distance to the object by stereo vision. Such a stereo camera device includes two left and right cameras spaced apart, compares the position of a target object in an image captured by these cameras, and detects the presence or absence of the object based on the difference, that is, parallax, Alternatively, the distance to the object is calculated.

In order to increase the distance resolution of such a stereo camera device, the parallax may be increased, and for this purpose, the distance between the optical axes of the left and right cameras, that is, the base line length may be increased. However, if the base line length is too long, the target object does not fit in the images captured by both cameras, and thus this method has a limit.

[0004] In this regard, in the stereo camera device disclosed in Japanese Patent Publication No. 5-27041, both cameras are positioned so that the target object is located at the center of the common range of the images captured by the two right and left cameras. Controlling. According to this technique, the base line length can be made as long as possible, and a high distance resolution can be obtained.

[0005]

However, in order to obtain a high distance resolution with the above-described conventional stereo camera device, it is necessary to increase the base line length by separating the cameras. There was also a limit to the length of the baseline because it moved together.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a stereo camera capable of acquiring an image of a predetermined imaging area even when a long base line is used and a high distance resolution is exhibited. It is to provide a device.

[0007]

In order to solve the above problems, the present invention comprises a first optical system and a first image pickup device for acquiring an image formed by the first optical system. First
And the second imaging means, which is spaced apart from the first imaging means,
And a second image pickup means provided with a second image pickup device for acquiring an image formed by the second optical system, wherein the first optical system comprises: ,
The second optical system has an imaging area larger than the imaging area of the second imaging element, and the first optical system has an imaging area larger than the imaging area of the first imaging element. The imaging device is provided so as to be movable in a baseline direction, the second imaging device is provided so as to be movable in a baseline direction, and a predetermined imaging region is formed on the first and second imaging devices. Features.

In the present invention, the first and second optical systems have an imaging area larger than the imaging area of the first and second imaging elements, respectively. The first and second imaging elements are both provided so as to be movable in the base line direction, that is, in the direction in which the first and second optical systems approach, and the first and second imaging elements are moved so that the imaging range deviates from the center of the imaging range. The mounting positions of the first and second imaging elements can be adjusted. For this reason, it is possible to widen the overlap of the images captured by the first and second image pickup devices for the base line length, and to obtain the long distance resolution by making the base line length as long as possible.

In one aspect of the present invention, the apparatus further comprises an interlocking mechanism for interlocking the first and second imaging elements so that the movement amounts of the first and second imaging elements are equal. I do. In this aspect, when the first image sensor is moved in the baseline direction, the second image sensor also moves by the same distance. In this case, the mounting positions of the first and second imaging elements can be set efficiently.

Further, the present invention provides a first optical system and the first optical system.
A first image pickup device provided with a first image pickup device for acquiring an image formed by the optical system, and a second optical system and the second optical system which are arranged separately from the first image pickup device A second imaging unit having a second imaging device for acquiring an image formed by the first imaging device, wherein the first optical system has an imaging area of the first imaging device. Having a larger imaging area than the second optical system.
Having an imaging area larger than the imaging area of the imaging element of
The first imaging element is arranged such that an imaging area thereof is shifted in a baseline direction with respect to an imaging area formed by the first optical system,
The second imaging element is arranged such that its imaging region is shifted in a baseline direction with respect to an imaging region formed by the second optical system,
It is characterized in that a predetermined imaging region forms an image on the first and second imaging elements.

In the present invention, the first and second optical systems have an imaging area larger than the imaging area of the first and second imaging elements, respectively. Then, the imaging region of the first and second imaging elements is shifted from the imaging region of the first and second optical systems in the base line direction, that is, the direction in which the first and second optical systems approach. . For this reason, it is possible to widen the overlap of the images captured by the first and second image sensors for the base line length, and to obtain the long distance resolution by making the base line length as long as possible.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a front view showing the overall configuration of a stereo camera device according to one embodiment of the present invention. As shown in the figure, this stereo camera device has image pickup device bases 31 and 32 and image pickup devices (CCD) 41 and 42.
And optical systems (lenses) 21 and 22. Image sensor base 31, image sensor 41, and optical system 2
Reference numeral 1 denotes a first camera (imaging unit), and the imaging element base 32, the imaging element 42, and the optical system 22 constitute a second camera. Although not shown here, an image processing device is electrically connected to the imaging elements 41 and 42. The imaging element bases 31 and 32 are moved in the base line direction while maintaining the parallelism between the imaging surfaces of the imaging elements 41 and 42 and the imaging surfaces of the optical systems 21 and 22. Mechanism is installed.

As shown in FIG. 1, optical systems 21 and 22 are spaced apart from each other at the same height above the reference plane R.
Image pickup devices 41 and 42 are arranged on these image forming surfaces. The image pickup devices 41 and 42 are each composed of an image pickup device base 3
1, 32, and this imaging element base 3
By moving the lenses 1 and 32 in the baseline direction, the imaging area of the imaging elements 41 and 42 is shifted from the imaging area of the optical systems 21 and 22. That is, the optical systems 21 and 22 have relatively wide imaging ranges S1 and S2, respectively, as indicated by the broken lines in FIG.
Numerals 1 and 42 capture an image of a part thereof. That is, the optical systems 21 and 22 have an imaging area of the imaging element 4.
The specifications are selected so as to be wider than the imaging area of the imaging device 1, 42. Here, the imaging area is determined by the optical system 2
It is governed by a comprehensive angle of 1 and 22, that is, an angle range in which a clear image can be formed. When the imaging plane is circular,
It is called an image circle.

When the image sensor bases 31 and 32 are positioned at an initial position, that is, a position where the optical axes 11 and 12 of the optical systems 21 and 22 and the centers of the image sensor bases 31 and 32 coincide with each other, the image sensors 41 and 42 operate. Images of the imaging region W ′ are respectively acquired. This imaging area W 'is
The optical systems 21 and 22 are set at the center positions of the two imaging regions.
The optical axes 11 and 12 pass through the center of the imaging region W ′ and also pass through the center of the imaging region. In the state shown in the figure, since the distance between the optical systems 21 and 22 is wide and the base line length X is too long, there is no overlap in the imaging regions W 'of the imaging elements 41 and 42. Therefore, in this stereo camera device, the imaging regions of the imaging devices 41 and 42 are moved inward, that is, in a direction in which the two imaging regions approach each other, by moving the imaging device bases 31 and 32 in the baseline direction. After the movement, the imaging devices 41 and 42 acquire an image of the imaging region W. In this way, both images include the entire target object M. Here, the moving amounts of the imaging elements 41 and 42 are made equal, and the imaging regions W of the imaging elements 41 and 42 are made equal. However, if the entire image of the target object M is included, the two are shifted. There is no problem.
In this case, an overlapping portion of both images may be extracted at the stage of image processing, and may be used as a target image for image processing.

Such a stereo camera device is provided with a mechanism for moving the image pickup element bases 31, 32 in the base line direction as described above. FIG. 2 shows the image sensor base 3
It is a top view which shows the example of a mechanism for moving 1 and 32 to a base line direction. In these mechanisms, the image sensor base 3
1 and 32 may be moved manually or may be driven by a power such as a motor. As the simplest configuration, as shown in FIG.
The image sensor bases 31 and 32 respectively attached with
What is necessary is just to move each independently. Further, the image pickup device base 3 is mounted on a rail 20 having a scale on the surface as shown in FIG.
1, 32 may be mounted so as to be movable along the rail 20.

Further, as shown in FIG. 1C, the racks 14 and 16 and the pinion 18 (both teeth are not shown) may be used to make the moving amounts of the imaging element bases 31 and 32 equal. . In this embodiment, the imaging element base 31
, The end of the rack 14 is fixedly attached, and the imaging element base 32 is fixedly attached to the end of the rack 16. The racks 14 and 16 are slidably attached to an apparatus main body (not shown) in parallel so that the tooth surfaces face each other. A pinion 18 that meshes with the teeth engraved on the racks 14 and 16 is rotatably mounted between the racks 14 and 16. This pinion 18 is also attached to the apparatus main body. Further, the tip of the rack 14 is slidably attached to a guided portion (not shown) provided on the back surface of the imaging element base 32, respectively.
6 is slidably attached to a guided portion (not shown) provided on the back surface of the imaging element base 31. Thus, the imaging element bases 31, 32 are guided by the racks 14, 16 in the movement in the base line direction, and have the same amount of movement.

Further, as shown in FIG. 1D, the movement amounts of the image pickup element bases 31, 32 may be made equal by the arms 28, 30 and the guide member 26. In this embodiment, the rail 24 is inserted through a guided portion (not shown) provided on the back surface of the image sensor bases 31 and 32, so that the image sensor bases 31 and 32 move in parallel in the base line direction. I have. The rail 24 is fixed to an apparatus main body (not shown). A guide member 26 having a rail frame formed therein is attached to the center of the rail 24, and the guide frame formed on the guide portion 26 is orthogonal to the guide direction of the rail 24. . Further, one ends of arms 28 and 30 having the same length are rotatably attached to the image sensor bases 31 and 32 at positions corresponding to each other by pins 34 and 36, respectively, and the other ends thereof are pins 38. It is fastened by.
The pin 38 is engaged with a guide frame formed on the guide member 26 so that the image sensor bases 31 and 32 are moved in the same amount.

The image pickup element bases 31, 32
The horizontal movement mechanism may be used, for example, when installing a stereo camera device. That is, as shown in FIG.
In a case where the comprehensive angle of the optical systems 21 and 22 is constant, if the distance between the optical systems 21 and 22 and the reference plane R is reduced, the image sensor 4
The overlapping range becomes narrower in the images photographed at 1, 42. For this reason, when the stereo camera device is installed, the imaging element bases 31 and 32 are moved in the base line direction in accordance with the distance between the optical systems 21 and 22 and the reference plane R, and the overlapping range of both images is secured as necessary. Then, after the start of operation, an image processing device connected to the imaging devices 41 and 42 cuts out an area to be actually subjected to stereo image processing from the captured image.

The present invention is not limited to the embodiment described above. For example, in the above description, the case where the optical axes 11 and 12 of the optical systems 21 and 22 are parallel to each other has been described. However, even when the optical axes 11 and 12 are non-parallel, the image pickup devices 41 and 42 are connected. It may be moved on the image plane.

[0021]

As described above, according to the present invention, the first
And the second optical system have an imaging area larger than the imaging area of the first and second imaging elements, respectively, and the imaging area of the first and second imaging elements respectively correspond to the first and second imaging elements.
Is shifted in the base line direction from the image formation area of the optical system of (1), so that the overlap of images captured by the first and second image pickup devices can be widened for the base line length, and the base line The length can be increased to obtain a high distance resolution.

[Brief description of the drawings]

FIG. 1 is a front view showing an overall configuration of a stereo camera device according to an embodiment of the present invention.

FIG. 2 is a plan view showing an example of a mechanism for moving an imaging element base in a base line direction.

[Explanation of symbols]

M (imaging) target object, R reference plane, S1, S2 imaging area, W, W 'imaging area, X base line length, 11, 12
Optical axis, 14,16 rack, 18 pinion, 20,2
4 rails, 21 and 22 optical systems, 26 guide members,
28, 30 arm, 31, 32 image sensor base, 3
4, 36, 38 pins, 40 command input unit, 41, 42
Imaging device.

Claims (3)

[Claims] 1. A first optical system comprising: a first optical system; and a first imaging device for acquiring an image formed by the first optical system.
And the second imaging means, which is spaced apart from the first imaging means,
And a second image pickup means provided with a second image pickup device for acquiring an image formed by the second optical system, wherein the first optical system comprises: An imaging area larger than an imaging area of the first imaging element, the second optical system has an imaging area larger than an imaging area of the second imaging element, The image sensor is provided so as to be movable in a baseline direction, and the second image sensor is provided so as to be movable in a baseline direction,
A stereo camera device, wherein a predetermined imaging area forms an image on the first and second imaging elements. 2. The stereo camera device according to claim 1, further comprising an interlocking mechanism that interlocks the first and second imaging elements so that the movement amounts of the first and second imaging elements are equal. A stereo camera device, characterized in that: 3. A first optical system comprising: a first optical system; and a first image sensor for acquiring an image formed by the first optical system.
And the second imaging means, which is spaced apart from the first imaging means,
And a second image pickup means provided with a second image pickup device for acquiring an image formed by the second optical system, wherein the first optical system comprises: An imaging area larger than an imaging area of the first imaging element, the second optical system has an imaging area larger than an imaging area of the second imaging element, The imaging element is arranged such that its imaging area is shifted in the base line direction with respect to the imaging area formed by the first optical system, and the second imaging element has its imaging area formed by the second optical system. Is displaced in the base line direction with respect to the image area,
A stereo camera device, wherein a predetermined imaging area forms an image on the first and second imaging elements.