JPH0758990A - Camera - Google Patents

Abstract

PURPOSE:To provide a cemra which can easily photograph an inclined subject in a state without one-sided narrowing or upper/lower narrowing and which can prevent photographing with improper shifting control. CONSTITUTION:The camera having a lens unit 1 holding an image pickup lens 1 forming a photographing optical axis O and an image pickup element 4 so that they can integrally turn by applying the image pickup element 4 is provided. The facing status degree of the subject is detected by using multiarea AF information. Then the shifting correction, namely, the parallel shifting control is performed for obtaining a photographing picture in the state where one-sided narrowing or upper/lower narrowing, etc., is not caused and a whole image-forming surface is in focusing state based on the information. Furthermore, alarm display is executed when the facing status degree of the subject is out of a permissible range.

Description

Detailed Description of the Invention

[0001]

[Industrial applications]

The present invention relates to a camera, and more particularly to a camera capable of tilt and shift driving.

2. Description of the Related Art When the subject to be photographed is in a state where the degree of confrontation is poor with respect to the photographing optical system of the camera,
For example, when trying to shoot a blackboard diagonally from the edge or when shooting a tall building from below, with conventional large-sized cameras, parallel tilt adjustment is performed so that the shooting optical system faces the subject. I was taking pictures with no dents.

Incidentally, the above-mentioned state of facing is shown in FIG.
As shown in FIG.
The optical axis O of 2 is orthogonal. In addition, the parallel tilt adjustment means that the optical axis O faces the subject as shown in FIG. 14, and the image plane 103 is kept perpendicular to the optical axis O while keeping the target subject. A tilt adjustment operation for shifting to the image forming position. When shooting is performed with this parallel tilt adjustment, the magnification of the size of the subject image on the same screen does not change, and an image with no one-sided dents or upper and lower dents is obtained.

On the other hand, as for the conventional camera using the image pickup device, various cameras for moving the image pickup device to adjust the tilt have been proposed. For example, actual fairness 1-152
A tilt movement device for a solid-state image sensor in a captured image recording apparatus disclosed in Japanese Patent Laid-Open No. 58 has a mechanism for shifting or tilting the position of the solid-state image sensor with respect to an imaging lens according to a subject by a photographer's manual operation. Is. Further, the photoelectric conversion surface tilting device for a television camera disclosed in Japanese Patent Application Laid-Open No. 1-91574 is applicable to a television camera, and shifts of an image sensor,
Alternatively, the tilt can be continuously performed even during shooting, and the photographer specifies the shift amount, that is, the parallel movement direction moving amount, and the tilt amount, that is, the tilt amount, The above adjustment is performed.

Further, the tilting photographing device disclosed in Japanese Patent Laid-Open No. 3-159377 detects the tilt of the object surface by using the focus information generating means, and tilts the image pickup device according to the detected tilt of the object surface. It is a photographing device.

[0006]

However, in the photographed image recording apparatus disclosed in the above-mentioned Japanese Utility Model Publication No. 1-158258, and in the tilting apparatus of the television camera disclosed in Japanese Patent Application Laid-Open No. 1-91574, the camera is The inclination of the subject has not been detected, and the photographer has to observe the state of the subject and arbitrarily specify the tilt angle and the like. Further, the operation such as changing the optical path of the imaging lens system is not performed.

Further, the tilting photographing apparatus disclosed in the above-mentioned Japanese Patent Laid-Open No. 3-159377 detects the inclination of the subject, and the tilting is automatically set.

FIG. 15 is a diagram showing a state of the tilt correction operation by the tilt shooting device 113 disclosed in Japanese Patent Laid-Open No. 3-159377. As shown in the figure, when the subject 110 is tilted with respect to the photographing device 113, a tilt angle α indicating the degree of tilt of the subject 110 with respect to the photographing device 113 is detected. Then, based on the inclination degree, the image pickup element 112 is driven for tilt correction, that is, shift and tilt, so that the entire image forming surface 112a of the subject 110 is in focus. Then, all the imaging planes of the near and far subjects are in focus.

However, since this photographing apparatus does not perform the above-described parallel tilt adjustment, in the photographing state shown in FIG. 15, both end portions 112a1 at the image plane 112a.
And 112a2 have different magnifications due to differences in subject distances along the respective optical axes O.
It becomes an image of the lower bud. In this photographing state, especially for the purpose of photographing a subject such as a character or a figure on a blackboard or an open book, the screen is distorted and a preferable photographing screen cannot be obtained.

Therefore, in order to take an image of a tilted subject without any one-sided dents or upper and lower dents, a camera incorporating the parallel tilt adjustment mechanism is proposed as in the case of the large-sized camera. It was also possible. However, in such an image pickup apparatus, the photographer needs to check the degree of facing of the subject each time the image is taken, set the optical axis direction of the image pickup lens, and perform focusing. Furthermore,
It was also necessary to confirm whether or not the degree of the above-mentioned confrontation was within the allowable range, and it was necessary to perform extremely complicated and sophisticated operation and confirmation.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to easily perform photographing without tilting one side or upper and lower sides even on a tilted subject.
Moreover, it is an object of the present invention to provide a camera that facilitates shooting in a state other than the facing state.

[0012]

The camera of the present invention is a face-to-face recognition for recognizing the degree to which the image pickup lens and the image pickup surface of the image pickup element optically face the surface of the subject. Means and, when the degree of facing recognized by the facing degree recognizing means deviates from a predetermined limit value, an alarm means for displaying or issuing an alarm to that effect. .

[0013]

The degree of confrontation of the subject is recognized by the degree of confrontation recognition means, and it is determined whether or not the degree of the degree of confrontation deviates from a predetermined limit value. Display or issue an alarm.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a camera showing a first embodiment of the present invention. The present camera is a camera to which an image pickup element is applied, and holds an image pickup lens 1 and an image pickup element 4 forming an image pickup optical axis O integrally rotatably, and a multi-area A.
The F (autofocus) distance measurement method is applied to detect the degree of the camera facing the subject, and based on the information, there is no one-sided dent or top-bottomed dent, and moreover, the entire image plane is matched. It is a camera capable of tilt correction, that is, parallel tilt adjustment to obtain a shooting screen in a focused state.

FIG. 2 is an optical path diagram showing the parallel tilt adjusting operation state of the camera. As shown in the figure, when the camera body 100 is aimed at the subject 120, the subject 1 is the degree of facing the subject before the parallel tilt adjustment.
The angle α of the photographing optical axis O ′ with respect to 20 is detected. Parallel tilt adjustment is performed based on the information of the angle α. That is, the imaging lens 3 and the imaging element 4 are rotated to a position where the photographing optical axis O is orthogonal to the subject 120. Then, the subject 12
The image forming surface 4a of the image pickup device 4 is shifted to the image forming position of 0.

The structure of the present camera will be described with reference to FIG. 1. The subject image is captured by an image sensor 4 through an imaging lens 3 incorporated in the lens unit 1 and converted into an image signal, which is then transferred to an image signal processing circuit 2. Is output. The video output of the image pickup signal processing circuit 2 is output to a recording system (not shown). Further, the lens unit 1 further includes a stepping motor (M) 5 for focusing and driving the image pickup lens 3 and an image pickup element shift mechanism 6 described later for shifting the image pickup element 6. The lens barrel body 23 (see FIG. 4) that supports the image pickup lens 3 and the image pickup device 6 is rotationally driven by the facing mechanism 10.

The focus motor 5, shift mechanism 6,
The facing mechanism 10 is a system control circuit 1 respectively.
It is driven by a focus motor drive circuit 7, a shift mechanism drive circuit 8, and a facing mechanism drive circuit 9 controlled by 5. The system control circuit 15 is
It is composed of U, ROM, RAM and the like.

Further, the distance measuring light emitting element 11 is driven by the AF distance measuring circuit 13 on the basis of the timing control signal from the system control circuit 15, and emits distance measuring light toward the object. The distance measuring light is reflected by the subject, and the distance measuring areas A and B in the upper and lower positions and the distance measuring areas C and D in the left and right positions on the photographing screen 19 shown in FIG. As the distance light, the light receiving elements 12a, 12
b and the light receiving elements 12c and 12d.

The light receiving elements 12a, 12b, 12c, 12
The output signal of d is taken into the system control circuit 15 as distance measurement information. Then, based on the distance information, the degree of facing of the subject is recognized by the degree-of-facing recognition built in the system control circuit 15. That is, the up and down facing degree is recognized by the output signals of the light receiving elements 12a and 12b, and the left and right facing degree is recognized by the output signals of the light receiving elements 12c and 12d. The lens barrel main body 23 of the lens unit 1 is driven to face the Y and X axes in accordance with the vertical and horizontal facing degree information.

Further, the focus position of the image pickup lens 3 and the shift amount of the image pickup element 4 are calculated based on the distance measurement information. Further, the focusing drive and the shift drive are executed. However, the focus position of the image pickup lens 3 is set to a focus position in consideration of a change in subject distance due to the facing drive.

When the facing degree of the subject recognized by the facing degree recognizing means deviates from a predetermined limit value and the facing drive of the lens unit 1 is impossible,
The system control circuit 15 outputs a warning display signal, which indicates that the degree of confrontation deviates from a predetermined limit value, to a finder (not shown), an LCD display unit or the like via the warning display circuit 14. The warning display may be alarm means for issuing a warning.

FIG. 4 is a perspective view of the lens unit mechanism incorporated in the camera of this embodiment. This lens unit mechanism is a mechanism that allows the lens frame body 23 to rotate in two directions θx and θy by two sets of rotating members 24 and 25 via an outer spherical surface portion 23b as shown in the figure. . The main configuration of the mechanism includes the lens unit 1, the image pickup element block 35, and the facing mechanism 10 of the lens unit 1.

The lens unit 1 has an image pickup lens 3, a driven and supported spherical surface portion 23b, and a guide groove 23a extending parallel to the optical axis O direction. A lens frame body 23 rotatably supported about horizontal and vertical axes X and Y about a point G through which O passes.
A focus drive focus motor 5 for driving the focusing lens 3 built in the lens frame body 23, and a motion restricting part for restricting rotation around the optical axis O (hereinafter referred to as rolling restriction). A cylindrical rotation restricting pin 30 slidably fitted in the guide groove 23a, and two spherical receiving members 28 for restricting movement in the optical axis direction, which are receiving parts on the lower surface side of the spherical surface part 23b. The spherical receiving member 29 serves as a receiving portion on the side surface side of the spherical surface portion 23b. In the neutral state of rotation as shown in FIG. 4, the optical axis O coincides with the Z axis.

Further, the facing mechanism 10 has X and Y axis rotary members 24 and 25, which are spherical rotary members whose surfaces are friction members, and X and Y rotary members 24 and 25.
It is composed of X and Y axis stepping motors 31 and 32 that are driven via the axial worm gear boxes 26 and 27. The X and Y axis rotating members 24 and 25 are the same as the spherical portion 2
3b are brought into contact with each other in a substantially point contact relationship, and are brought into rolling contact with each other in order to give a displacement to be rotationally driven in predetermined directions. Further, it has a function of regulating the position of the lens frame body 23 in the horizontal and vertical directions in the X and Y axis directions via the spherical surface portion 23b. The image sensor block 35 includes the image sensor 4 and the shift mechanism 6 of the image sensor 4, and the details of the shift mechanism will be described later.

FIG. 5 is a side view of the lens frame body 23. Further, FIG. 6 is a view on arrow A of FIG. As shown in FIG. 5, when the lens frame body 23 is supported by the support portions 28 and 29 and is rotated about the X axis, for example, the optical axis O of the lens frame body 23 is rotated.
Is rotated to the O'direction.

FIG. 7 is a perspective view of the shift mechanism 6 inside the image pickup device block 35. This shift mechanism 6
Is a mechanism for performing shift driving of the image pickup device 4 along the X axis and the Y axis which are orthogonal to the optical axis O. Image sensor 4
Is fixed to a first base 41 having an opening for imaging light that faces the image plane 4a. The first base 41
Is X by the guide shaft 42 held by the second base 43.
It is slidably supported in the axial direction. The second base 43
Is set to Y by the guide shaft 44 held by the third base 45.
It is slidably supported in the axial direction. Third base 4 above
5 is fixed to the lens frame body 23 of the lens unit 1.

An X-axis shift motor 48 is supported on the second base 43, and a pinion 47 fixed to the output shaft of the motor 48 meshes with a rack 46 attached to the first base 41. ing. In addition, the third
A Y-axis shift motor 51 is supported by the base 45, and a pinion 50 fixed to the output shaft of the motor 51 meshes with a rack 49 attached to the second base 43. In the shift mechanism 6 as described above, Y, X
When the shaft shift motors 51 and 48 are driven, the second base 43 or the first base 41 is driven in the Y and X axis directions via the rack 49 or 46, and the image pickup device 4 is shift-driven.

The subroutine "shooting preparation process" in the shooting sequence of the camera of the present embodiment configured as described above will be described with reference to the flowchart of FIG. 8 and the block diagram of FIG. The shooting preparation process is a subroutine process that is called when the camera body 100 shown in FIG. 2 is aimed at the subject and the release button is half-pressed there.

As shown in FIG. 8, in step S1, based on the output signals of the light receiving elements 12a to 12d,
Distance measuring area A on the screen 19 of the subject shown in FIG.
Distance measurement of B, C, D is performed. Then, in step S2,
Based on the distance measurement information of the areas A, B, C, and D, the optical axis of the camera body 100, that is, the optical axis O ′ in the neutral state of the lens frame body 23 with respect to the subject surface, which is the degree of facing the subject.
Angle α (see FIG. 2) is calculated. Note that this angle α
Is displayed as the inclination angle on the horizontal plane in FIG. 2,
Actually, the angle between the two directions of the vertical direction and the horizontal direction, that is, the vertical inclination angle α1 obtained from the distance measurement data of the upper and lower distance measurement areas A and B, and the distance measurement data of the left and right distance measurement areas C and D. The tilt angle α2 in the left-right direction is calculated.

Subsequently, in step S3, AF driving of the image pickup lens 3 is performed based on the distance measurement information. In step S4, it is determined whether the subject is tilted with respect to the camera body 100, that is, whether the tilt angle α is 0 °. If it is not tilted, it is not necessary to perform parallel tilt processing, so this routine is ended as it is. If it is determined that the subject is tilted, the process proceeds to step S5.

In step S5, it is determined whether or not the tilt angle α of the subject exceeds a permissible range in which the lens frame body 23 can be rotated for face-up correction. If the allowable range is exceeded and the face-to-face adjustment drive is impossible, the process jumps to step S9. In step S9, a display signal indicating that the face-to-face correction is impossible is output to the display device (not shown) via the warning display circuit 14, and the display is performed.

If it is determined in step S5 that the rotation drive for the face-to-face adjustment is possible, the process proceeds to step S6, and the rotation drive amount of the face-up mechanism of the lens unit 1 is calculated. . As the rotation driving amount, the direction of the optical axis O is the angle α, specifically, the above-mentioned vertical inclination angle α1.
Since the lens frame body 23 is rotated by the inclination angle α2 in the left-right direction, the rotation angle is the Y-axis and the X-axis of the lens frame body 23. However, in reality,
The rotation angle is obtained as the number of drive pulses for the Y-axis and X-axis step motors 32 and 31.

In step S7, the shift amount of the image sensor 4 is calculated. As the shift amount, in the case of the state shown in the photographing optical path diagram of FIG. 9, the distance L1 to the object 120, the inclination angle α of the object surface, the image forming position L2, the focal length f of the imaging lens 3
Then, 1 / f = (1 / L1) + (1 / L2) …………………… (1) Furthermore, tan (α) = x / L2 …………… (2) Then, from the above equations (1) and (2), the shift amount x
Is represented by x = ((L1 * f) / (L1-f)) * tan ([alpha]) ... (3).

For example, when the lens focal length f is 35 mm,
When the subject distance L1 is 2 m, the inclination of the subject 15
The shift amount x for 9 °, 30 ° and 45 ° is 9.
54 mm, 20.6 mm and 35.6 mm. Next, in step S8, parallel tilt drive of the rotational drive angle α of the lens frame body 23 and the shift amount x of the image sensor 4 obtained in steps S6 and 7 is performed, and this routine is ended.

As described above, according to the camera of this embodiment, the distances of four areas of the object are measured by the four light receiving elements to obtain the degree of confrontation of the object, and the image pickup lens and the image pickup element are parallel to each other. Face-to-face drive while being held at
Perform parallel tilt adjustment. By this parallel tilt adjustment, the subject is, for example, a character on a blackboard or a printed character on a book, and even if the subject is tilted with respect to the camera, there is no one-sided dent, or a state in which no dented up or down. You can shoot at. Further, when the degree of facing the subject deviates from the parallel tilt adjustable range of the camera,
By displaying a warning to that effect, the photographer can be made aware that normal parallel tilt adjustment is not possible, and it is possible to prevent poor photography.

Further, according to the present embodiment, since the image pickup lens and the image pickup element are constituted by an integrated unit, the image pickup lens and the image pickup element are always maintained in a parallel relationship. The parallel tilt adjustment can be realized with a simple structure without the need to separately provide the facing drive means.

Next, a modified example of the camera of the first embodiment will be described. This modification is different from the camera of the first embodiment in that the distance measuring method is a passive method and the distance information of the subject is obtained from the contrast information extracted from the image pickup signal of the image pickup device, that is, This is a point configured to obtain the degree of confrontation of the subject by the imager distance measuring method. FIG. 10 is a block diagram of the camera of the above modification. The configuration of this modification is different from that of the first embodiment only in the components related to the imager distance measuring method, and the other configurations are the same. Therefore, the same components are designated by the same reference numerals as in the block diagram of FIG. 1, and the description thereof will be omitted.

In this modification, an image pickup signal of a subject output from the image pickup signal processing circuit 2 is fetched into a BPF (bandpass filter) 61, and contrast data is extracted from the image pickup signal. In the area division circuit 62,
The contrast data is divided into four contrast data corresponding to areas A, B, C and D on the photographing screen shown in FIG. The A / D conversion circuit 63 performs A / D conversion of each contrast data and outputs the output signal to the system control circuit 15.

Then, in the system control circuit 15, the number of steps of the motor at the in-focus position for each of the areas A, B, C and D is grasped, and the amount of extension of the focus lens is obtained from the value. The subject distance information is calculated from the amount of extension of the focus lens to obtain the degree of confrontation of the subject. Parallel tilt adjustment is performed based on this face-to-face degree information, and the processing operation is the same as that of the camera of the first embodiment.

According to this modification, a light emitting element for performing multi-area distance measurement, like the camera of the first embodiment,
It is not necessary to dispose a plurality of light receiving elements and the like, and it is possible to use the output data of the image pickup element, which is advantageous in terms of cost because there are few constituent members.

Next, a camera showing the second embodiment of the present invention will be described. The camera of this embodiment is replaced with the rotatable lens frame body 23 applied to the camera of the first embodiment.
In front of the image pickup lens, as shown in the schematic layout of the camera in FIG. 11, a mirror unit 76 rotatable as a facing mechanism.
, The imaging lens 73 is not rotationally driven, and
The image pickup device 74 is characterized by performing only shift driving. However, the other components are the same as those of the camera of the first embodiment. In FIG. 11, 70 is a camera body and 75 is a protective glass.

FIG. 12 is a perspective view showing the main structure of the mirror unit 76. In the present mirror unit 76, the mirror 81 is rotatably supported by the support frame 82 via the X support shaft 83. Further, the support frame 82 is
It is rotatably supported by the base 84 via a Y support shaft 85. Then, the mirror 81 is rotationally driven about the X axis by an X axis drive motor 87 via a gear 86 fixed to the X support shaft 83. Further, the support frame 82 is
A Y-axis drive motor 89 rotates the Y-axis about the Y-axis via a gear 88 fixed to the Y-support shaft 85. The base 84 is fixed to the camera body 70.

FIG. 13 shows the state of parallel tilt adjustment in the camera of the present embodiment having the above-described structure. First,
In a state where the camera body 70 of the present embodiment is directed to the tilted subject 120, the mirror unit 76 is located at the neutral rotation position 76 (A). The image sensor 74 is also located at the neutral shift position 74 (A). Therefore, the distance measuring areas A, B, as shown in the photographing screen 19 of FIG.
The distance measurement information of C and D is detected, and the degree of confrontation of the subject 120, that is, the inclination angle α (α1, α2) of the subject 120 with respect to the neutral optical axis O ′ is calculated.

When the parallel tilt adjustment is performed on the tilted object 120, the mirror unit 76 is rotated from the rotation position 76 (A) by 1/2 of the calculated tilt angle α to rotate the position 76. Position (B). In this state, the optical axis O passing through the image pickup lens 73 is in a state of directly facing the subject surface.

Further, in order to position the image forming surface of the image pickup device 74 at the image forming position of the object 120, the image pickup device 74 is shift-driven from the neutral shift position 74 (A) to the shift position 74 (B). The shift amount is the same as the shift amount x shown in the equation (3).

As described above, the camera according to the present embodiment does not require the rotatable lens frame body as in the camera according to the first embodiment, but includes the rotatable mirror unit 76 having a simple structure. Since it is sufficient to provide the camera, it is possible to reduce the size and weight of the camera. Further, when the facing drive is performed, it is only necessary to rotate the mirror unit, the control is easy, and the response speed can be improved.

[0047]

As described above, the camera of the present invention recognizes the degree of confrontation of a subject and enables photographing with the imaging lens and the image sensor facing each other. On the other hand, it is easy to take a picture without a single dent or upper and lower dents. Further, in a state where the degree of facing the subject deviates from the allowable range, a warning is issued. It is possible to prevent shooting in an inappropriate facing state.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a camera showing a first embodiment of the present invention.

FIG. 2 is an optical path diagram of the camera of FIG. 1 in a parallel tilt adjusting operation state.

3 is a diagram showing a distance measuring area of the camera shown in FIG. 1;

4 is a perspective view of a lens unit mechanism of the camera shown in FIG.

5 is a side view showing an operating state of a lens unit mechanism of the camera shown in FIG.

6 is a bottom view of the lens unit mechanism of the camera shown in FIG.

7 is a perspective view of a facing mechanism built in an image pickup element block of the lens unit mechanism of the camera shown in FIG.

8 is a flowchart of a subroutine "shooting preparation process" in the shooting sequence of the camera of FIG.

9 is an optical path diagram showing a shift state in the "imaging preparation process" of FIG.

10 is a block configuration diagram of a modified example of the camera of the first embodiment of FIG.

FIG. 11 is a schematic layout diagram of a camera of a second embodiment of the present invention.

12 is a perspective view of a mirror unit mechanism which is a facing mechanism of the camera shown in FIG.

FIG. 13 is an optical path diagram of the camera of FIG. 11 when parallel tilt adjustment is performed.

FIG. 14 is an optical path diagram when the camera faces the subject.

FIG. 15 is an optical path diagram in a state where tilt adjustment is performed in the camera of the conventional example.

[Explanation of symbols]

3,73 Image pickup lens 4,74 Image pickup element 12a, 12b, 12c, 12d ………… Light receiving element (correction degree recognition means) 13 ………… ………… AF distance measuring circuit (correctness recognizing means) 14 …………………… Warning display circuit (displaying means) 15 ……………… System control circuit (correctness recognizing means) 61 ………… ............ BPF (Straightness recognition means) 62 …………………… Area division circuit (Surfaceness recognition means) 63 ……………… A / D conversion circuit (Surfacement recognition means)

Claims (1)

[Claims] 1. A facing degree recognizing means for recognizing a degree to which an image pickup surface of an image pickup lens and an image pickup surface of a subject is optically facing the surface portion of a subject, and the above-mentioned face degree recognizing means. A camera, comprising: when the recognized degree of facing has deviated from a predetermined limit value, a display indicating this fact and an alarm means for issuing an alarm.