JP2003202635A - Image pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image pickup device of reduced size by making a mirror and the entire image pickup device smaller in size. <P>SOLUTION: This image pickup device has a plurality of plane mirrors 4 arranged pyramidally and a plurality of cameras 1 respectively arranged to be opposed to the mirrors 4. The incident angle of a light beam passing through the optical axis 7 of the lens 2 of the camera 1 on the mirror 4 is set to be <45°. <P>COPYRIGHT: (C)2003,JPO

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 capable of shooting a wide range such as all directions and all circumferences.

[0002]

BACKGROUND OF THE INVENTION As is well known, many video cameras have
Various cameras have been developed that are housed in one housing and simultaneously image in all directions or all around.

As one of the methods, for example, a method of eliminating parallax (parallax) generated between a plurality of cameras by virtually matching imaging viewpoints by using mirrors arranged in a polygonal pyramid shape is proposed. (US Patent 6
115176).

FIG. 6 shows a schematic configuration diagram of an example of an image pickup apparatus having a configuration using the above-mentioned mirrors arranged in a polygonal pyramid shape.
This image pickup device includes eight plane mirrors 44 arranged in a polygonal pyramid shape, in this case, an octagonal pyramid shape, and a camera 41 arranged so as to face each plane mirror 44. In FIG. 6, of these, two plane mirrors 44 and two cameras 41 on a vertical plane passing through the center line of the image pickup apparatus are shown.
It is shown. Each camera 41 is provided with a lens 42 and an image pickup element 43, and the lens 42 is attached to a camera body (not shown) in which the image pickup element 43 and other parts are housed, whereby the camera 41 is configured.

In this image pickup apparatus, the angle-of-view end ray 46A at the top of the angle of view, the angle-of-view edge ray 46B at the bottom of the angle of view, and the ray passing on the lens optical axis 47 are reflected by the mirror 44 and are reflected by the lens 42. The light enters and forms an image on the image sensor 43.

Then, in the plurality of cameras 41, parallax can be suppressed by making the virtual viewpoint center 45 by the plane mirror 44 substantially coincide with each other. As a result, images from a plurality of cameras 41 are pasted together to obtain an image in a wide range such as all directions or all around.

In the case of FIG. 6, the incident angle of the light ray passing through the lens optical axis 47 on the plane mirror 44 is 45 degrees. Therefore, the light ray passing through the lens optical axis 47 enters the plane mirror 44 horizontally, is reflected by the plane mirror 44, and enters the lens 42 in the vertical direction.

In the image pickup device of FIG. 6, the distance between the angle-of-view end ray 46A at the bottom of the angle of view and the tip angle of the lens 42 is CL.
Has become. In order to prevent the front end of the lens 42 from being reflected, that is, in order to capture an image without "vignetting", it is necessary that CL> 0. As shown in FIG. 6, it is the height HL from the top end of the mirror 44 to the bottom end of the camera 41 (up to the image sensor 43 in FIG. 6) and the octagonal pyramidal mirror that determine the size of the imaging device. 44 is the size LL of the upper end portion. Then, in order to downsize the imaging device, it is required to reduce the height HL and the size LL.

In order to reduce the height HL and the size LL, as shown in FIG.
2 and the image sensor 43) may be brought close to a plane mirror.
As a result, the plane mirror 44S can be made smaller than the plane mirror 44 of FIG. 6, and the height HS from the upper tip of the mirror 44S to the lower end of the camera 41 and the size LS of the upper end of the octagonal pyramidal mirror 44S. About HS <H
L and LS <LL. That is, the image pickup device can be downsized.

[0010]

However, in the case of FIG. 7, the distance between the ray at the bottom of the angle of view and the angle of the tip of the lens 42 is negative, and "vignetting" occurs. Therefore, it is inconvenient for imaging. Therefore, it is necessary that the distance C between the angle-of-view end ray at the bottom of the angle of view and the tip angle of the lens 42 has a positive value and is as small as possible.

At this time, the tip diameter D of the lens 42 of the camera 41 is a constraint for downsizing the image pickup apparatus.

From this, the camera 41 is moved to the distance C = 0.
It cannot be closer to the plane mirror than the position.
Further, as indicated by a broken line in FIG. 6, the size (particularly the width) of the camera body 41A accommodating the image sensor 43 and the like is equal to that of the lens 4
When the size of the camera 41 is considerably larger than that of 2, when the cameras 41 are brought closer to the plane mirror, the camera body 4 of each camera 41
1A will hit each other. For example, 3 as an image sensor
When one CCD image pickup device is used to form one camera, the camera body becomes large. From these constraints,
Further downsizing of the image pickup device has been difficult.

Further, in the configuration of the image pickup apparatus shown in FIG.
Since the plane mirror 44 and the optical axis 47 of the lens 42 of the camera 41 are in a positional relationship of an incident angle of 45 degrees, and this positional relationship determines the dimension of the plane mirror 44, as a result, the polygonal pyramidal mirror and the entire image pickup apparatus. The size increases. In particular, it is the plane mirror 4 that determines the size of the image pickup device.
4 is the height HL from the upper end of 4 to the lower end of the camera 41 and the size LL of the upper end of the pyramidal mirror 44.

Further, the values of the height HL and the size LL are also influenced by the distance C (CL in FIG. 6) between the ray at the lowest angle of view and the angle of the tip of the lens 42. It is necessary to set this distance C appropriately.

However, regardless of the value of the distance C, since the virtual viewpoint centers 45 of the plurality of cameras 41 can be made to substantially coincide with each other, the distance C can take an arbitrary value, and the conventional method can be used. Was not set to an appropriate value, the whole image pickup apparatus was enlarged.

In order to solve the above-mentioned problems, the present invention provides an image pickup apparatus which can be downsized by reducing the size of the entire mirror and the image pickup apparatus.

[0017]

An image pickup apparatus of the present invention has a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror. The angle of incidence of a light ray passing through the optical axis on the plane mirror is less than 45 degrees.

According to the above-mentioned configuration of the image pickup apparatus of the present invention,
Since the incident angle of the light ray passing through the optical axis of the camera lens with respect to the plane mirror is less than 45 degrees, the height from the upper end of the plane mirror to the lower end of the camera can be reduced, and the plane mirror is used. The bottom area of the polygonal pyramid can be reduced. This makes it possible to downsize the entire imaging device.

The image pickup device of the present invention has a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face the plane mirrors, respectively. D / A <4 and f / D> where D is the focal length of the lens and A is the diagonal length of the image sensor of the camera.
It satisfies 0.15.

According to the above-mentioned configuration of the image pickup apparatus of the present invention,
When the diameter of the tip of the lens of the camera is D, the focal length of the lens is f, and the diagonal length of the image sensor of the camera is A, D /
By satisfying A <4 and f / D> 0.15, it is possible to reduce the diameter D of the tip of the lens while the diagonal length A of the image sensor and the focal length f of the lens are fixed. Therefore, it becomes possible to downsize the imaging device.

The image pickup apparatus of the present invention has a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face the plane mirrors, respectively. 0 <C, where C is the distance to the light beam at the edge of the imaging angle of view and A is the diagonal length of the image sensor of the camera.
It satisfies <2A.

According to the configuration of the image pickup apparatus of the present invention described above,
When the distance from the tip angle of the lens of the camera to the closest ray of the imaging angle of view is C and the diagonal length of the imaging element of the camera is A, by satisfying 0 <C <2A, the pair of imaging elements is Since the distance C from the tip angle of the lens of the camera to the closest image pickup angle-of-view edge ray can be reduced in the state where the angle length A is determined, the image pickup apparatus can be downsized.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is an image pickup apparatus having a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror. It is an imaging device in which the incident angle of a light ray passing through the optical axis with respect to the plane mirror is less than 45 degrees.

Further, according to the present invention, in the above image pickup device, the plane mirror is arranged in the middle of a lens group including a plurality of lenses.

The present invention is an image pickup apparatus having a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror, and the diameter of the tip of the lens of the camera. Is D, the focal length of the lens is f, and the diagonal length of the image pickup element of the camera is A, the image pickup apparatus satisfies D / A <4 and f / D> 0.15.

The present invention is an image pickup apparatus having a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror. Assuming that the distance to the closest image pickup angle-of-view ray is C and the diagonal length of the image pickup element of the camera is A,
The imaging device satisfies 0 <C <2A.

FIG. 1 is a schematic block diagram of an image pickup apparatus as an embodiment of the present invention. FIG. 1 is a sectional view taken along a vertical plane passing through the center line of the image pickup apparatus.

This image pickup device has a polygonal pyramid shape, in this case 8
It comprises eight plane mirrors 4 arranged in a pyramid shape, and a camera 1 arranged so as to face each plane mirror 4 one by one. FIG. 1 shows two plane mirrors 4 and two cameras 1 in a vertical plane passing through the center line of the image pickup device. Each camera 1 is provided with a lens 2 and an image pickup element 3, and the lens 2 is attached to a camera body (not shown) in which the image pickup element 3 and the like are housed to configure the camera 1.

The incident light ray is reflected by the mirror 4, enters the lens 2, and forms an image on the image pickup element 3.

In the plurality of cameras 1, parallax can be suppressed by making the virtual viewpoint center 5 by the plane mirror 4 substantially coincide with each other. As a result, images from a plurality of cameras 1 are pasted together to obtain an image in a wide range such as all directions or all around.

In the image pickup apparatus of this embodiment, in particular, the incident angle of the light ray passing through the lens optical axis 7 to the plane mirror 4 is 35 degrees. The ray passing through the lens optical axis 7 is
The light is made incident on the plane mirror 4 horizontally, is reflected by the plane mirror 4, and is made incident on the lens 2 obliquely with respect to the vertical direction.

In this structure, the height of the entire image pickup device is the height H1 from the upper end of the plane mirror 4 to the lower end of the camera 1 (up to the image pickup element 3 in FIG. 1). This height H1
And the size L1 of the upper surface of the polygonal pyramid mirror are the dominant dimensions of the entire imaging device.

As another embodiment of the image pickup apparatus of the present invention, FIG. 2 shows a schematic block diagram of an image pickup apparatus having a modified configuration of the image pickup apparatus shown in FIG. In the present embodiment, the front lens group 8 is arranged in front of the plane mirror 4, and the plane mirror 4 is arranged between the front lens group 8 and the lens (rear lens group) 2 attached to the camera body. It has been configured. That is, the plane mirror 4 is arranged in the middle of the lens group including a plurality of lenses. Also in the image pickup apparatus of the present embodiment, the incident angle of the light ray passing through the lens optical axis 7 to the plane mirror 4 is 35 degrees.

In this structure, the height of the entire image pickup apparatus is the height HH1 of the front lens group 8. This height HH1
And the size L1 of the upper surface of the polygonal pyramid mirror are the dominant dimensions of the entire imaging device. Other configurations are the same as the configurations of the image pickup apparatus according to the previous embodiment shown in FIG. 1, and therefore, the same reference numerals are given and redundant description will be omitted.

Here, for comparison, an image pickup apparatus having a structure in which the incident angle of a light ray passing through the optical axis of the lens of the camera to the plane mirror is 45 degrees, as in the structure shown in FIGS. 6 and 7, is shown in FIG. And shown in FIG. In the image pickup apparatus shown in FIG. 1 and the image pickup apparatus shown in FIG. 8, the cameras 1 and 51 are configured by using the same lenses as the lenses 2 and 52. The distances to the plane mirrors 4 and 54 and the image pickup angle of view are the same. Also,
The imaging device shown in FIG. 9 is different from the imaging device shown in FIG.
A front lens group 58 similar to the front lens group 8 in FIG. 2 is added.

With respect to the image pickup devices shown in FIGS. 1 and 2, and the image pickup devices shown in FIGS. 8 and 9, the height of the entire image pickup device (from the upper ends of the plane mirrors 4, 54 to the cameras 1, 51). H1 to the lower end of the lens or the heights HH1 and HH of the front lens groups 8 and 58) and the sizes L1 and L of the upper surface of the polygonal pyramid mirror, H1 <H, HH
Since 1 <HH and L1 <L, it is clear that the sizes in FIGS. 1 and 2 are smaller.

That is, in each of the image pickup devices shown in FIGS. 1 and 2,
By setting the incident angle of the light ray passing through the optical axis 7 of the lens 2 to the plane mirror 4 to be 35 degrees, which is smaller than 45 degrees in FIG. 8 and FIG. It can be seen that the device can be downsized.

As described above, even when the camera body is large, the image pickup apparatus can be downsized without hitting the camera body, which is particularly effective when the camera body is large.

According to the configuration of the image pickup apparatus of each of the above-described embodiments, the incident angle of the light ray passing through the optical axis 7 of the lens 2 with respect to the plane mirror 4 is 35 degrees, so that the height of the entire image pickup apparatus is reduced. In addition, since the bottom area of the polygonal pyramid formed by the plane mirror can be reduced, the image pickup apparatus can be downsized.

Since the image pickup device can be downsized, it is possible to improve the installation flexibility and portability of the image pickup device. Further, since the optical components such as the mirror and the mechanical components supporting the optical components can be downsized, the manufacturing cost can be reduced and the parallax can be reduced by improving the precision of the components.

In each of the image pickup devices shown in FIGS. 1 and 2,
The incident angle of the light ray passing through the optical axis 7 of the lens 2 with respect to the plane mirror 4 is 35 degrees, but if the incident angle is less than 45 degrees, the image pickup device can be similarly downsized.

Next, FIG. 3 shows a schematic block diagram of still another embodiment of the image pickup apparatus of the present invention. This image pickup device is provided with eight plane mirrors 14 arranged in a polygonal pyramid shape, in this case, an octagonal pyramid shape, and a camera 11 arranged so as to face each plane mirror 14. In Figure 3,
Of these, the two plane mirrors 14 and the two cameras 11 which are in a vertical plane passing through the center line of the image pickup apparatus are shown. Each camera 11 is provided with a lens 12 and an image pickup device 13, and the camera 12 is configured by attaching the lens 12 to a camera body (not shown) that houses the image pickup device 13 and the like.

The incident light beam is reflected by the mirror 14, enters the lens 12, and forms an image on the image pickup device 13. Also,
The incident angle of the light ray passing through the lens optical axis 17 on the plane mirror 14 is 45 degrees.

Then, in the plurality of cameras 11, parallax can be suppressed by making the virtual viewpoint center 15 by the plane mirror 14 substantially coincide with each other. As a result, images from a plurality of cameras 11 are pasted together to obtain an image in a wide range such as all directions or all around.

In the present embodiment, especially the camera 11
A lens having a small diameter D3 at the tip of the lens is used as the lens 12. By configuring the lens 12 by adopting a lens having a small tip end diameter D3, the tip end angle of the lens 12 when the lens 12 is brought close to the plane mirror 14 as shown in FIG. The restriction (distance from the angle-of-view end ray 16B at the bottom of the angle of view to the tip angle of the lens 12> 0) can be relaxed, and the size of the imaging device can be further reduced. be able to.

Further, in this embodiment, the lens 12 of the camera 11 is constructed so as to satisfy the following conditional expression. D / A <4 (1) f / D> 0.15 (2) (where D is the diameter of the tip of the camera lens, A is the diagonal length of the image sensor of the camera, and f is the focal length of the lens. Respectively.)

The meanings of the conditional expressions (1) and (2) are as follows.
When (1) and (2) are satisfied, the diameter D of the tip portion of the lens becomes smaller than the size of the lens or the image sensor when the angle of view is more than a certain angle, and as a result, the size of the image capturing apparatus can be reduced. Becomes

Here, the grounds for conditional expressions (1) and (2) will be described. Assuming that a CCD solid-state image sensor or a CMOS type solid-state image sensor is used in a camera, the value of the diagonal length A of the normal image sensor is about 1 to 12 mm. Further, if the vertical angle of view is 2 × β, β ≦ 45 degrees (11) from the condition for preventing the lens itself from being reflected, and the relationship between β and A is 2f × tan β = A (12) holds. Therefore, from equations (11) and (12), f ≧ A / 2 (13).

Next, considering the value of the diagonal length A of the image pickup element, the case will be considered. (I) In the case of A = 1 mm, f ≧ 0.5 from the equation (13). Therefore, when f = 0.5 and substituting this into the conditional equation, (1) D <4 × A = 4 and ( 2) From D <f / 0.15, D <3.3 Therefore, D <3.3 mm Further, when f = 100 and substituting this into the conditional expression, (1) D <4 × A = 4 and (2) From D <f / 0.15, D <667 Therefore, when D <4 mm (ii) A = 3 mm, f ≧ 1.5 is obtained from the equation (13). (1) D <4 × A = 12 and (2) D <10 from D <f / 0.15, so D <10 mm and f = 100. Substituting this into the conditional expression, ) D <4 × A = 12 and (2) D <f / 0.15, D <667 Therefore, in the case of D <12 mm (iii) A = 6 mm, the formula (13 Therefore, if f = 3, and substituting this into the conditional expression, (1) D <4 × A = 24 and (2) D <f / 0.15, so D <20 Therefore, D < 20 mm Further, assuming that f = 100 and substituting this into the conditional expression, (1) D <4 × A = 24 and (2) D <f / 0.15, so D <667. Therefore, D <24 mm (iv) A = In the case of 12 mm, since f ≧ 6 from the equation (13), if f = 6 and substitute this into the conditional equation, (1) D <4 × A = 48 and (2) D <f / 0.15 <40 Therefore, D <40 mm Further, if f = 100 and this is substituted into the conditional expression, (1) D <4 × A = 48 and (2) D <f / 0.15, so D <667 Therefore, D <667 48 mm

On the other hand, in a video camera optical system, it is necessary to dispose a low-pass filter, an infrared cut filter, or a color separation prism for separating the three colors of R, G, and B after the lens. Needs a large back focus compared to. This causes the diameter D of the tip portion of the imaging lens to be increased. Under the above conditions, the diameter D of the tip portion of the imaging lens in (i) to (iv) is a sufficiently small value and is also a realizable size.

Next, it will be explained by making a specific example that the diameter D of the distal end portion of the image pickup lens is small, which contributes to downsizing of the entire image pickup apparatus.

Here, for example, the angle-of-view end ray 1 at the bottom of the angle of view
6B and the angle C3 between the tip of the lens 12 and C3 = 0.
85 mm, the diameter D3 of the tip of the lens 12 is D3
= 15 mm and the length E3 of the lens 12 is E3 = 18
mm, the angle of view α of the lens 12 corresponding to the rectangular long side of the image sensor 13 is α = 60 degrees, the diagonal length A3 of the image sensor 13 is A3 = 6 mm, and the focal length f of the lens 12 is
3 is f3 = 4.5 mm. Substituting the above numerical values into the equations (1) and (2), D / A = D3 / A3 = 15/6 = 2.5 <4 f / D = f3 / D3 = 4.5 / 15 = 0.3> It becomes 0.15, which satisfies the conditional expression.

Further, in the case of the above-mentioned dimensional structure, the height H3 from the upper end to the lower end of the plane mirror 14 and the size L3 of the upper surface of the pyramidal mirror which govern and determine the size of the image pickup device are: H3 = 59 mm and L3 = 155 mm.
Plane mirror 14 including lens 12 as well as mirror 14.
The height from the upper end to the lower end of the lens 12 is 90 mm. The size of the entire image pickup apparatus further includes the size of the camera 11.

According to the above-described present embodiment, the camera 11
The diameter D3 of the tip of the lens 12, the focal length f3 of the lens 12, and the diagonal length A3 of the image sensor 13 of the camera 11.
With respect to D3 / A3 <4 and f3 / D3> 0.15, the diagonal length A3 of the image sensor 13 and the focal length f3 of the lens 12 are determined, that is, the same camera 11 is used. In this case, since the diameter D3 of the tip portion of the lens 12 can be made smaller, the image pickup device can be made smaller.

Since the image pickup device can be downsized, it is possible to improve the installation flexibility and portability of the image pickup device. Further, since the optical components such as the mirror and the mechanical components supporting the optical components can be downsized, the manufacturing cost can be reduced and the parallax can be reduced by improving the precision of the components.

On the other hand, in the image pickup apparatus having the arrangement shown in FIG. 3, let us consider the size of the image pickup apparatus when neither of the expressions (1) and (2) is satisfied. For example, in the case where the diameter D3 of the tip of the lens 12 is 30 mm, the diagonal length A3 of the image sensor 13 having a rectangular shape with long sides: short sides of 4: 3 = 6 mm, and the focal length of the lens 12 is f3 = 4.5. In the formula (1)
Satisfies D / A = D3 / A3 = 30/6 = 5> 4 and does not satisfy the condition. Further, the equation (2) is also f / D = f3 / D3 = 4.
5/30 = 0.15, which does not satisfy the condition. In this case, if the one having a larger angle of view in the height direction (that is, the longer side direction of the image sensor 13) is used, the height from the upper end to the lower end of the plane mirror 14, which determines the size of the device, is determined. H3
And the size L3 of the upper surface of the pyramidal mirror is H3 = 136
mm, L3 = 369 mm, which is impractical when it is mounted on a stage for photographing or when photographing the inside of a small passenger car.

Further, for example, the diameter D of the tip of the lens 12
When the diagonal length A3 of the image sensor 13 is 3 = 15 mm, the long side: the short side is 4: 3, and the focal length f3 of the lens 12 is 2.25, the formula (1) is D / A = D
3 / A3 = 15/3 = 5> 4 and the condition is not satisfied.
Further, the equation (2) is also f / D = f3 / D3 = 2.25 / 15 =
It becomes 0.15 and the condition is not satisfied. In this case, if the one having a larger angle of view in the height direction (that is, the longer side direction of the image sensor 13) is used, the height from the upper end to the lower end of the plane mirror 14, which determines the size of the device, is determined. H3 and the size L3 of the upper surface of the pyramidal mirror are H3 = 76 mm and L3 = 1.
The size is 96 mm, which is a large image pickup device in spite of using a small image pickup element having a diagonal length A3 = 3 mm.

Further, in the image pickup apparatus having the arrangement shown in FIG. 3, let us consider the size of the image pickup device when the expression (1) is satisfied but the expression (2) is not satisfied. For example lens 12
If the diagonal length A3 of the image sensor 13 having a rectangular shape with a long side: short side of 4: 3 mm and a focal length f3 of the lens 12 is f3 = 1, the formula ( 1) is D
/A=D3/A3=7/2=3.5<4, which satisfies the condition. However, the equation (2) is f / D = f3 / D3 = 1/7
= 0.14 <0.15 is not satisfied. In this case, if the one having a larger angle of view in the height direction (that is, the longer side direction of the image sensor 13) is used, the height from the upper end to the lower end of the plane mirror 14, which determines the size of the device, is determined. H3
And the size L3 of the upper surface of the pyramidal mirror is H3 = 182
mm, L3 = 390 mm, and a small image pickup element having a diagonal length A3 = 2 mm is used, and the diameter D of the tip portion of the lens 12 is made small, resulting in a large image pickup apparatus.

Next, FIG. 4 shows a schematic block diagram of another embodiment of the image pickup apparatus of the present invention. This image pickup device includes eight plane mirrors 24 arranged in a polygonal pyramid shape, in this case an octagonal pyramid shape, and a camera 21 arranged so as to face each plane mirror 24. FIG. 4 shows the two plane mirrors 24 and the two cameras 21 in the vertical plane passing through the center line of the imaging device. Each camera 21 is provided with a lens 22 and an image pickup device 23, and the camera 22 is configured by attaching the lens 22 to a camera body (not shown) in which the image pickup device 23 and the like are housed.

The incident light beam is reflected by the mirror 24, enters the lens 22, and forms an image on the image pickup device 23. Also,
The incident angle of the light ray passing through the lens optical axis 27 on the plane mirror 24 is 35 degrees.

In the plurality of cameras 21, parallax can be suppressed by making the virtual viewpoint center 25 by the plane mirror 24 substantially coincide with each other. As a result, images from a plurality of cameras 21 are combined to obtain an image in a wide range such as all directions or all around.

Also in this embodiment, as the lens 22 of the camera 21, a lens having a small diameter D4 at the tip of the lens is adopted. By configuring the lens 22 by adopting a lens having a small tip end diameter D4 in this way, when the lens 22 is brought close to the plane mirror 24, the lens 2
The restriction for preventing "vignetting" at the tip angle of 2 can be relaxed, and the image pickup apparatus can be further downsized.

Further, in the present embodiment, the conditional expression (1) described above for the lens 12 of the camera 21 is used.
It is configured to satisfy (2). That is, this embodiment is
The configuration that satisfies the conditional expressions (1) and (2) is combined with a configuration in which the incident angle of a light ray passing through the lens optical axis to the plane mirror is less than 45 degrees.

Here, for example, the angle-of-view end ray 2 at the bottom of the angle of view
The distance C4 between 6B and the tip of the lens 22 is C4 = 1m
m, and the diameter D4 of the tip of the lens 22 is D4 = 9 m
m, the length E4 of the lens 22 is E4 = 17 mm, the angle of view α of the lens 22 corresponding to the rectangular long side of the image sensor 23 is α = 60 degrees, and the diagonal length A4 of the image sensor 23 is A4 = 6 mm and the focal length f4 of the lens 22 is f4
= 4.5 mm. The above numerical value (1)
Substituting into equation (2), D / A = D4 / A4 = 9/6 = 1.5 <4 f / D = f4 / D4 = 4.5 / 9 = 0.5> 0.15 Meet

Further, in the case of the above-described dimensional configuration, the height H4 from the upper end to the lower end of the plane mirror 24 and the size L4 of the upper surface of the pyramidal mirror, which govern and determine the size of the image pickup device, are H4 = 74 mm and L4 = 171 mm.
Plane mirror 24 including lens 22 as well as mirror 24
The height from the upper edge of the lens to the lower edge of the lens 22 is 111 mm
Becomes In addition, the size of the entire imaging device further includes the size of the camera 21.

According to the above-described present embodiment, the camera 21
The diameter D4 of the tip of the lens 22, the focal length f4 of the lens 22, and the diagonal length A4 of the image sensor 23 of the camera 21.
With respect to D4 / A4 <4 and f4 / D4> 0.15, the diagonal length A4 of the image sensor 23 and the focal length f4 of the lens 22 are determined, that is, the same camera 21 is used. In this case, since the diameter D4 of the tip portion of the lens 22 can be made smaller, the image pickup device can be made smaller.

Since the image pickup device can be downsized, it is possible to improve the installation flexibility and portability of the image pickup device. Further, since the optical components such as the mirror and the mechanical components supporting the optical components can be downsized, the manufacturing cost can be reduced and the parallax can be reduced by improving the precision of the components.

On the other hand, in the image pickup apparatus having the arrangement shown in FIG. 4, let us consider the size of the image pickup apparatus when the expression (2) is satisfied but the expression (1) is not satisfied. For example, in the case where the diameter D4 of the tip of the lens 22 is 36 mm, the diagonal length A4 of the image pickup device 23 having a long side: short side of 4: 3 is 4: 3, and the focal length f4 of the lens 22 is 4.5. In the formula (1)
Satisfies D / A = D4 / A4 = 36/6 = 6> 4 and does not satisfy the condition. Formula (2) is f / D = f4 / D4 = 4.5 /
36 = 0.125 <0.15, which satisfies the condition. In this case, the plane mirror 2 that governs the size of the device
4, the height H4 from the upper end to the lower end and the size L4 of the upper surface of the pyramidal mirror are H4 = 140 mm or more, L4 =
When the size is 400 mm or more, the line of sight of the spectator is blocked when the image is set on the stage for shooting, and the size becomes impractical. Further, when an image is to be taken in a narrow space such as the interior of a small passenger car, the size of the device is an obstacle, and the image cannot be taken physically.

Next, FIG. 5 shows a schematic block diagram of still another embodiment of the image pickup apparatus of the present invention. This image pickup device includes eight plane mirrors 34 arranged in a polygonal pyramid shape, in this case, an octagonal pyramid shape, and a camera 31 arranged so as to face each plane mirror 34. In FIG.
Of these, the two plane mirrors 34 and the two cameras 31 which are in a vertical plane passing through the center line of the image pickup apparatus are shown. Each camera 31 is provided with a lens 32 and an image pickup element 33, and the lens 32 is attached to a camera body (not shown) in which the image pickup element 33 and the like are housed to configure the camera 31.

The incident light beam is reflected by the mirror 34, enters the lens 32, and forms an image on the image pickup device 33. Also,
The incident angle of the light ray passing through the lens optical axis 37 to the plane mirror 34 is 45 degrees.

In the plurality of cameras 31, parallax can be suppressed by making the virtual viewpoint center 35 by the plane mirror 34 substantially coincide with each other. As a result, images from a plurality of cameras 31 are pasted together to obtain an image in a wide range such as all directions or all around.

In this embodiment, in particular, the distance C5 between the angle-of-view end ray 36B at the lowest angle of view and the tip angle (corner) of the lens 32 is made sufficiently small. By thus sufficiently reducing the distance C5 between the angle-of-view end beam 36B at the lowest angle of view and the tip angle of the lens 32, it is possible to further reduce the size of the imaging device.

Further, in the present embodiment, the lens 32 of the camera 31 is constructed so as to satisfy the following conditional expression. 0 <C <2A (3) (where C is the distance between the angle-of-view end ray at the bottom of the angle of view and the tip angle of the camera lens, and A is the diagonal length of the image sensor of the camera).

The above-mentioned conditional expression means that the distance between the ray at the bottom of the angle of view and the angle at the tip of the lens is made sufficiently small with respect to the size of the image pickup element. It is possible to configure the omnidirectional camera.

Here, for example, the ray 3 at the bottom of the angle of view
6B and the distance C5 between the tip angle of the lens 32 and C5 = 0.
36 mm, the diagonal length A5 of the image sensor 33 is A5 = 6
mm. Substituting the above numerical values into the equation (3), C = C5 = 0.36 and 2A = 2 · A5 = 1
Since it is 2, 0 <C <2A, which satisfies the conditional expression.

In the case of the above-described dimensional structure, the height H5 from the upper end of the plane mirror 34 to the lower end of the camera 31 (the lower end of the image pickup device 33 in FIG. 5), which determines the size of the image pickup device, is determined. And the size L5 of the upper surface of the pyramidal mirror is
H5 = 42 mm and L5 = 56 mm.

According to the above-described present embodiment, the distance C5 between the angle-of-view end ray 36B at the bottom of the angle of view and the tip angle of the lens 32 of the camera 31 and the diagonal length A of the image pickup device 33 of the camera 31.
By satisfying 0 <C5 <2 · A5 for 5,
When the diagonal length A5 of the image sensor 33 is fixed, that is, when the same camera 31 is used, the distance C5 between the angle end ray 36B at the bottom of the angle of view and the tip angle of the lens 32 of the camera 31 is set to Since the size can be made smaller, the size of the image pickup device can be reduced.

Since the image pickup device can be downsized, it is possible to improve the installation flexibility and portability of the image pickup device. Further, since the optical components such as the mirror and the mechanical components supporting the optical components can be downsized, the manufacturing cost can be reduced and the parallax can be reduced by improving the precision of the components.

Each of the above-mentioned configurations of the present invention, that is, a configuration in which the incident angle of a light ray passing through the lens optical axis to the plane mirror is less than 45 degrees, conditional expressions (1) D / A <4 and (2) f. / D
> 0.15 and conditional expression (3), 0 <C <2A, it is possible to combine two or three configurations to form an image pickup apparatus. It is possible to reduce the size of the imaging device.

The present invention is not limited to the above-mentioned embodiments, and various other configurations can be adopted without departing from the gist of the present invention.

[0081]

As described above, according to the present invention, it is possible to reduce the size of the image pickup apparatus for photographing a wide range. Therefore,
Due to the miniaturization of the image pickup device, it is possible to improve the installation flexibility and portability of the image pickup device, and it is also possible to miniaturize the optical parts such as mirrors and the mechanical parts that support the optical parts.
It is possible to reduce parallax by reducing manufacturing costs and improving parts accuracy.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an image pickup apparatus of the present invention.

FIG. 2 is a schematic configuration diagram of another embodiment of the image pickup apparatus of the present invention.

FIG. 3 is a schematic configuration diagram of still another embodiment of an image pickup apparatus of the present invention.

FIG. 4 is a schematic configuration diagram of another embodiment of an image pickup apparatus of the present invention.

FIG. 5 is a schematic configuration diagram of yet another embodiment of an image pickup apparatus of the present invention.

FIG. 6 is a schematic configuration diagram of an example of an imaging device configured to use mirrors arranged in a polygonal pyramid shape.

7 is a diagram showing a configuration in which a camera is close to a plane mirror with respect to the image pickup apparatus of FIG.

FIG. 8 is a schematic configuration diagram of an example of an imaging device configured to use mirrors arranged in a polygonal pyramid shape.

9 is a schematic configuration diagram of an image pickup apparatus having a configuration in which a lens front group is added to the image pickup apparatus in FIG.

[Explanation of symbols]

1,11,21,31 camera, 2,12,22,32
Lens, 3,13,23,33 Image sensor, 4,1
4,24,34 plane mirrors, 5,15,25,35
Center of viewpoint, 8 lens front group

Claims (4)

[Claims] 1. An image pickup apparatus comprising a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror, wherein the light beam passes through an optical axis of a lens of the camera. The image pickup device, wherein the incident angle with respect to the plane mirror is less than 45 degrees. 2. The image pickup apparatus according to claim 1, wherein the plane mirror is arranged in the middle of a lens group including a plurality of lenses. 3. An imaging device comprising a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror, wherein a diameter of a tip portion of a lens of the camera is D, the focal length of the lens is f, and the diagonal length of the image sensor of the camera is A, D / A <4 and f / D> 0.15 are satisfied. 4. An imaging device having a plurality of plane mirrors arranged in a polygonal pyramid shape and a plurality of cameras arranged so as to face each plane mirror, the camera being the most distant from the tip angle of the lens of the camera. An image pickup apparatus characterized by satisfying 0 <C <2A, where C is a distance to an image pickup angle-of-angle light ray which is close to the image pickup angle end ray, and A is a diagonal length of the image pickup element of the camera.