JP2002229137A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mitigate the occurrence of parallax, in the case of connecting several videos and forming a wide video. SOLUTION: An image pickup means 4 with an NP point N on a side opposite to a CCD imaging device 6 is constituting by arranging the CCD imaging device 6 with a stay at the focal position of a convex mirror 5, and the image pickup device is constituted by arranging several image pickup means 4 around the NP point N in a state where the coincidence of the NP point N is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus, in which parallax between images to be pasted together to form a wide-range image is reduced.

[0002]

2. Description of the Related Art In order to obtain a wide area image such as a panoramic image by taking a point in a space as a viewpoint and photographing the surrounding area on a horizontal plane, a plurality of cameras are arranged at equal intervals along a circumference centered on the viewpoint. It is conceivable to arrange the images and fix the optical axes of the respective cameras in the radial direction, and connect the images captured by the respective cameras.

FIG. 12 shows an arrangement in which four video cameras 1 are arranged at 90-degree intervals in order to obtain a wide-range image of 360 degrees around a horizontal plane. The angle of view θ in the horizontal direction of the video camera 1 is required to be 90 degrees or more, and an overlapping portion a occurs in the shooting range of the adjacent video cameras 1,
Parallax occurs in this part.

Since the value of the parallax varies depending on the distance from the video camera, it is difficult to determine which distance is used as a reference when pasting adjacent images, and this hinders automation.

On the other hand, in order to eliminate the parallax, it is necessary to set such that the ends of the image determined by the angle of view θ are adjacent to each other as shown in FIG. In order to achieve such a state, it is necessary that the position of the NP point (described later) N, which is the vertex of the angle of view θ, be arranged at the same point in the four video cameras 1.

[0006]

However, the position of the NP point N of the video camera 1 depends on the angle of view θ and the effective diameter d of the lens, which are defined as parameters for designing a plurality of lenses in the lens barrel 1a shown in FIG. The position is uniquely located between the outermost lens 1b and the imaging surface, and as can be seen from FIG. 13, the four video cameras 1 interfere with each other and make the NP point N the same point. Placement is physically impossible.

Therefore, an object of the present invention is to provide an image pickup apparatus which solves the above problem.

[0008]

According to a first aspect of the present invention, there is provided an image pickup apparatus configured to divide an object to be photographed into a plurality of parts to be photographed, An image pickup apparatus comprising a plurality of image pickup means for individually picking up an image of a portion to be imaged, and obtaining a wide-range image by pasting images from the respective image pickup means, wherein a principal ray passing through a center of a diaphragm provided in the image pickup means is provided. Then, a principal ray passing through the Gaussian region is selected, and a point intersecting the optical axis by extending a linear component in the object space of the principal ray is set as an NP point, and the imaging unit faces the portion to be imaged. A concave mirror having an NP point on a side opposite to the portion to be imaged, and a photoelectric conversion unit disposed at a focal position of the concave mirror and receiving light reflected by the concave mirror and converting the light into electricity. And claim 2 Configuration of the imaging apparatus according, in claim 1, characterized by using the imaging device as the photoelectric conversion unit, the configuration of an imaging apparatus according to claim 3, claim 2
The method according to claim 1, wherein another NP point is arranged in an NP point area inside a sphere centered on any one of the NP points among the NP points in each imaging means. The configuration of the imaging apparatus according to claim 4 is characterized in that, in claim 3, the radius of the NP point region is set to approximately 20 mm, and the configuration of the imaging apparatus according to claim 5 is that in claim 4, It is characterized in that an elimination means for eliminating infrared rays reaching the element is provided.

The NP point and the NP point area are defined below. FIG. 11 illustrates a state in which light reflected by a subject (not shown) reaches the imaging unit 301 via the equivalent convex lens 300 and forms an image on the imaging unit 301. The equivalent convex lens expresses a group of a single or a plurality of lenses for forming an image on the imaging unit as one convex lens, and not only a lens but also a convex mirror or a concave mirror is a component of the equivalent convex lens. Here, the equivalent convex lens 300 includes lenses 302 to 308, and an aperture 309 is provided between the lens 304 and the lens 305. Among the innumerable chief rays passing through the center of the stop 309, a chief ray 311 whose lens aberration is negligible is selected through a Gaussian region near the optical axis 310, and a straight line in the object space 312 among the selected chief rays 311 is selected. A point where the component is extended and intersects with the optical axis 310 is defined as an NP (non-parallax) point 313, and a radius of 20 m centered on the NP point
The inside of the sphere within m is the NP point area 314. The reason why the NP point area is within the sphere having a radius of 20 mm centered on the NP point is that the NP point of another imaging means is located within the sphere having a radius of 20 mm centered on the NP point in any one of the imaging means. Further, if the NP points are close to each other, the occurrence of parallax can be suppressed to a negligible level. 315 is an image space.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an imaging apparatus according to the present invention will be described.

(A) First Embodiment FIG. 1 shows an imaging apparatus according to a first embodiment of the present invention. As shown in the figure, an imaging group 3 is provided on a base 10 via a support 2. The imaging group 3 includes a plurality of imaging units 4.

FIG. 2 shows the structure of the image pickup means 4. A substantially circular concave mirror 5 is provided, and a protective film 5a is formed on the inner peripheral surface thereof. As the protective film 5a, a film (exclusion means) having a property of absorbing only an infrared portion of the light incident on the concave mirror 5 is used. At the position of the focal point in the concave mirror 5, a CCD image pickup device (photoelectric conversion unit) 6 is arranged.
The CCD image sensor 6 is provided with a concave mirror 5 through a plurality of stays 7.
It is supported by. A processing means 8 and a connector 9 are attached to the outside of the concave mirror 5, and the CCD imaging device 6 is provided by a flexible substrate 16 disposed along the stay 7.
Are connected to the processing means 8 and the connector 9. The flexible board 16 is shielded as necessary in order to clear regulations such as FCC (Federal Communications Commission). In addition,
All or a part of the processing means 8 may be constituted by a bare chip mount or the like in the portion of the CCD image sensor 6.

Next, the relationship between the light and the concave mirror 5 is shown in FIG. The angle of view θ depends on the relationship between the CCD image sensor 6 and the concave mirror 5.
Is determined. That is, the concave mirror 5
The angle θ formed by extending the light S and T incident on the CCD imaging device 6 after being reflected by the CCD imaging device 6 is the angle of view. The point where the lights S and T intersect on the optical axis is the NP point N. The position of the NP point N is in a space on the opposite side of the concave mirror 5 from the CCD image pickup device 6. As described above, since the position of the NP point N exists in the space on the opposite side of the CCD image sensor 6, the NP points N in the plurality of image pickup means 4 are arranged at the same point in the space, and the plurality of concave mirrors 5 It is possible to arrange so as to surround the point N.

In view of the above, the image pickup apparatus shown in FIG. 1 is provided with twelve image pickup means 4 around the NP point N by arranging the NP points N at the same point. However, only the imaging means 4 on the lower surface is deleted, and the column 2 is inserted in the deleted portion. A mounting base 11 is connected to the upper end of the support column 2, and eleven imaging units 4 are detachably mounted on the mounting base 11 via a bayonet (detachment unit) 12.

In order to minimize parallax, the outer shape of the concave mirror 5 is optimized according to the number of imaging units 4 used. For example, as in the first embodiment, the imaging device
In the case of a regular dodecahedron in which 12 can be arranged, the outer shape of the concave mirror 5 is a regular pentagon. In this case, if the photographing range is determined and the angle of view is determined, the external shape of the concave mirror 5 will be determined.

FIG. 4 shows the structure of the bayonet 12. The bayonet 12 includes fixed members 13 and 14 and a movable member 15. The fixing member 13 includes a rectangular mounting plate 13b having a hole 13a for inserting a screw (not shown) through a flat portion 11a formed on the mounting base 11, a cylindrical portion 13c integrated with the mounting plate 13b, and a cylindrical portion 13c. And a hexagonal fitting hole 13e formed in the end face of the cylindrical portion 13c. The fixing member 14 is attached to the concave mirror 5 via a screw (not shown), a supporting portion 14c having a flange portion 14b, and the fitting hole 13e.
And a hexagonal column portion 14d for determining the angle. The movable member 15 has an inner diameter corresponding to the outer diameter of the cylindrical portion 13c and the flange 14b, and a cylindrical portion 15a having an inner diameter at the right end corresponding to the support 14c.
And a lock groove 15b into which the pin 13d is inserted. The hexagonal column portion 14d is fitted into the fitting hole 13e and the pin 1
By inserting the 3d into the lock groove 15b and rotating the movable member 15, the eleven imaging means 4 are detachably connected to the mounting base 11.

The bayonet 12 may be used not only for mechanical attachment but also for electrical ground connection. Further, by providing a conductive coating on the back surface of the concave mirror 5 and connecting it to the mounting base 11 via the bayonet 12, an electric shield can be obtained. Further, a screw may be used instead of the bayonet.

FIG. 5 shows an electric signal processing block diagram. The CCD image sensor 6 is driven by the timing generator 17, and the output signal of the CCD image sensor 6 is
, And AD converted by the A / D converter 16. Then, this digital signal is sent to the signal processing unit 18.
And the signal is output. This signal processing method is exactly the same as that of a video camera currently generally manufactured.

As shown in FIG. 1, a wiring 20 connected to each connector 9 in FIG. 2 controls a power supply, a video monitor, and a control device 21 for controlling camera parameters (iris, shutter speed, white balance, etc.). It is connected to a recording device 22 such as a hard disk or a VTR via the hard disk.

As shown in FIG. 1, the total number of the imaging means 4 is 11
The angle of view of the concave mirror 5 is theoretically set to 72 degrees with a slight overlap. The mounting table 11 is set small so that the position of the NP point N of the concave mirror 5 intersects at one point. Adjacent concave mirrors 5 need to be in contact with one line, and it is difficult to completely design in this way. However, even if the NP point N does not become one point, the NP point N
Parallax can be reduced if they approach each other.

The case of taking a picture using such an image pickup apparatus will be described. In FIG. 6, the NP points N of the respective imaging means 4 are arranged so as to share the same point. The eleven imaging units 4 have the same configuration, and the eleven imaging units 4 shoot a wide area video. For this reason, the photographing range (the part to be photographed) by the adjacent image pickup means 4 is (a),
(B) and (c), and the boundary lines when the images from the respective image pickup means 4 are combined are b, c, and d. Then, the image from each imaging means 4 also becomes a regular pentagon.

As the configuration of the concave mirror, an inner peripheral surface of a transparent material may be coated with an infrared ray transmitting characteristic so that only the infrared ray is transmitted and other light is reflected. Alternatively, a stay having high thermal conductivity may be used and a heat sink may be attached.

(B) Second Embodiment Next, a second embodiment will be described. FIG. 7 shows a part of the imaging means according to the second embodiment. This is a concave mirror 5
In order to prevent contamination of the CCD, the concave mirror 5 is covered with a protective glass 23 and hermetically sealed.
Is provided.

As shown in the figure, the flexible substrate 26 and the connector 27 are adhered to the inner surface of the protective glass 23, while the transparent electrode 28 and the anisotropic conductor 29 are attached to the protective glass 2.
The CCD image sensor 6 is attached between the connector 27 and the anisotropic conductor 29.
Another anisotropic conductor 30 is provided at the outer end of the transparent electrode 28.
Is connected. 2, the other end of the flexible substrate 16 whose one end is connected to the processing means 8 is connected to the anisotropic conductor 30. Flexible substrate 26
Is connected to the timing generator 17 shown in FIG. The power of the CCD image sensor 6 is supplied by the flexible substrate 26, but when CMOS is used as the image sensor and the power consumption is very small, a transparent electrode may be used.

In this case, as compared with the case where the CCD image pickup device 6 is supported using the stay, the aperture effect is small and the decrease in the brightness of the lens is alleviated. In addition, the light shielding area is reduced by the amount of the use of the transparent electrode 28, and the amount of light incident on the CCD image sensor 6 is increased.

Incidentally, the CCD image pickup device 6 and the like may be provided outside the protective film 23. Further, since infrared rays are reflected by the concave mirror 5 and the temperature of the CCD imaging device 6 rises, an infrared absorbing glass (exclusion means) may be used as the protective glass 23.

The other configuration and operation are the same as those of the first embodiment, and the description is omitted.

(C) Third Embodiment Next, a third embodiment will be described. As shown in FIG. 8A, a mounting plate 25 is mounted on the concave mirror 5 of the imaging means 4 via a plurality of stays 7, and the CCD imaging device 6 is mounted on the mounting plate 25. The concave mirror 5 is made of aluminum, and is formed by mirror-finish or mirror-coating the inner peripheral surface. The mounting plate 25 and the stay 7 are integrally formed of a material having high thermal conductivity. As shown in FIG. 8B, a fin 5b for heat radiation is formed on the outer peripheral surface of the concave mirror 5.

In such an image pickup device, since the light is reflected by the concave mirror 5 and enters the CCD image pickup device 6, the CCD image pickup device 6
Is generated, and this heat is transmitted through the mounting plate 25, the stay 7, and the concave mirror 5, and is released from the fin 5b.

The other configuration and operation are the same as those of the first embodiment, and the description is omitted.

Incidentally, a heat pipe may be used as the stay 3. Such a countermeasure against heat is effective when a CCD image pickup device is used, but is effective as a countermeasure against heat when a heat source such as the sun is photographed even when a CMOS is used.

(D) Fourth Embodiment Finally, a fourth embodiment will be described with reference to FIG. In this embodiment, the shape of the concave mirror 5 is set to be circular, and the concave mirrors 5 are in contact with each other at points e, f, and G.

The NP points N of the concave mirror 5 in such an image pickup apparatus are separated from each other as shown in FIG. 10, and a parallax occurs in the overlap portion h. However, when the distance between the NP points N is sufficiently small, the occurrence of parallax can be sufficiently reduced. As shown in FIG. 9, the concave mirrors 5 can be brought into contact at one point or separated from each other. And a circular concave mirror 5 can be used.

In the embodiment, the case where the NP points of all the image pickup means coincide with each other has been described. However, if another NP point is arranged in any one of the NP point areas in the image pickup means, the parallax is obtained. Can be suppressed to a negligible extent.

[0035]

As can be seen from the above description, claim 1
According to the imaging devices of (1) to (5), since the imaging device is configured by providing a plurality of imaging units each including a concave mirror and a photoelectric conversion unit disposed at the focal position of the concave mirror, the NP point is opposite to the photoelectric conversion unit. And any one of N in the imaging means
Other NP points can be arranged in the P point area, and a wide-range image without parallax can be obtained.

Further, according to the imaging apparatus of the fifth aspect, since the elimination means for eliminating the infrared rays directed to the photoelectric conversion unit is provided, heat generation in the photoelectric conversion unit is reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of an imaging device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an imaging unit that forms the first embodiment of the imaging apparatus according to the present invention;

FIG. 3 is an explanatory diagram of an NP point in an image pickup unit that forms the first embodiment of the image pickup apparatus according to the present invention;

FIG. 4 is a configuration diagram of a bayonet in the imaging device according to the first embodiment of the present invention;

FIG. 5 is an electric signal processing block diagram of an imaging unit that forms the first embodiment of the imaging apparatus according to the present invention;

FIG. 6 is an explanatory diagram showing the operation of the imaging device according to the first embodiment of the present invention;

FIG. 7 is a cross-sectional view of an imaging unit that constitutes an imaging device according to a second embodiment of the present invention.

FIGS. 8A and 8B are sectional views and FIG. 8B is a rear perspective view of an imaging device according to a third embodiment of the imaging apparatus according to the present invention.

FIG. 9 is a configuration diagram of a coupling portion between imaging means that constitutes an imaging device according to a fourth embodiment of the present invention.

FIG. 10 is an explanatory diagram of an NP point of an imaging unit that constitutes an imaging device according to a fourth embodiment of the present invention.

FIG. 11 is an explanatory diagram for defining an NP point and an NP point area of the imaging means according to the present invention.

FIG. 12 is an explanatory diagram of parallax occurrence when video cameras are arranged at every 90 degrees in the horizontal direction.

FIG. 13 is an explanatory diagram showing that parallax does not occur if the positions of NP points substantially coincide with each other when the video cameras are arranged every 90 degrees in the horizontal direction.

FIG. 14 is a configuration diagram showing a position of an NP point of the video camera.

[Explanation of symbols]

 4 ... Imaging means 5 ... Concave mirror 6 ... CCD imaging device N ... NP point (A)-(C) ... Shooting range

Claims (5)

[Claims] 1. A plurality of image pickup means for separately dividing a part to be photographed into a plurality of parts to be photographed and photographing each part to be photographed, and pasting an image from each image pickup means. In addition, an imaging apparatus that obtains a wide-range image, wherein a principal ray that passes through a Gaussian region is selected from among principal rays that pass through the center of an aperture provided in the imaging unit, and a linear component in the object space of the principal ray is selected. Extend and intersect the optical axis with N
P is set as the point, and the imaging means faces the portion to be imaged and N
A concave mirror having a point P on the side opposite to the portion to be imaged, and a photoelectric conversion unit arranged at a focal position of the concave mirror and receiving light reflected by the concave mirror and converting the light into electricity. Imaging device. 2. The imaging device according to claim 1, wherein an imaging device is used as the photoelectric conversion unit. 3. An NP point is arranged in an NP point area inside a sphere centered on one of the NP points among the NP points in each image pickup means. The imaging device according to claim 2, wherein: 4. The radius dimension of the NP point region is approximately 20 mm
The imaging device according to claim 3, wherein: 5. The imaging apparatus according to claim 4, further comprising an exclusion unit that eliminates infrared rays reaching the imaging device.