Control device, lens device, imaging apparatus, camera system, control method, and program

Abstract

To provide a control device that can continue to focus with high accuracy even when obtaining a tilt effect and a shift effect.SOLUTION: A control device is used for a camera system having a lens device comprising an optical system including: an imaging apparatus that comprises an image pickup device; and a focus member that performs focusing with at least one optical member for changing at least one of a tilt effect of tilting a focus surface with respect to an imaging surface of the image pickup device and a shift effect of moving a photographic range. The control device has: an acquisition unit that acquires information indicating an optical state of the optical system; and a control unit that corrects an out-of-focus state occurring due to the movement of the at least one optical member by using the information indicating the optical state of the optical system.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a control device, a lens device, an imaging device, a camera system, a control method, and a program.

Background Art

[0002] Conventionally, an optical system has been proposed that can obtain a tilt effect of tilting the focus plane to achieve good focus overall on an object plane tilted with respect to the optical axis of the imaging optical system, and a shift effect of moving the shooting range. Patent Document 1 discloses an optical system that can obtain a tilt effect and a shift effect by moving two optical elements in a direction perpendicular to the optical axis.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the optical system of Patent Document 1, since the change in the amount of defocus due to moving the optical element in the direction perpendicular to the optical axis is not considered, when trying to obtain a tilt effect or a shift effect after focusing and moving the optical element in the direction perpendicular to the optical axis, the focus will shift.

[0005] An object of the present invention is to provide a control device that can continuously focus with high accuracy even when obtaining a tilt effect or a shift effect.

Means for Solving the Problems

[0006] One aspect of the present invention is a control device used in a camera system having an imaging device equipped with an image sensor and a lens device having an optical system that includes at least one optical member for changing at least one of a tilt effect that tilts the focal plane with respect to the imaging plane of the image sensor and a shift effect that moves the shooting range, and a focusing member for focusing, characterized in that it comprises an acquisition unit for acquiring information indicating the optical state of the optical system and a control unit for correcting the focus shift caused by the movement of at least one optical member using the information indicating the optical state of the optical system. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a control device that can maintain high-precision focusing even when tilt or shift effects are obtained. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view of the camera system according to the first embodiment. [Figure 2] This is an electrical configuration diagram of the camera system. [Figure 3] This is an explanatory diagram of the Scheinproof principle. [Figure 4] This diagram shows the configuration necessary for correcting the focus error in the first embodiment. [Figure 5] This figure shows the focus correction information for the first embodiment. [Figure 6] This is a flowchart showing the focus correction method of the first embodiment. [Figure 7] This diagram shows the configuration necessary for correcting the focus error in the second embodiment. [Figure 8] This figure shows the focus correction information for the second embodiment. [Figure 9] This is a flowchart showing the focus correction method of the second embodiment. [Modes for carrying out the invention]

[0009] The embodiments of the present invention will be described in detail below with reference to the drawings. In each figure, the same reference numeral is used for identical components, and redundant explanations are omitted. [First Embodiment] Figure 1(a) is a cross-sectional view of the camera system 1 according to this embodiment. The camera system 1 includes a lens barrel (lens device) 2 and a camera (imaging device) 3. The lens barrel 2 and the camera 3 are connected via a mount 5 provided on the lens barrel 2 and a mount (not shown) provided on the camera 3, and can communicate with each other via a lens-side communication unit 17 provided on the lens barrel 2 and a camera-side communication unit 18 provided on the camera 3. The lens-side communication unit 17 and the camera-side communication unit 18 each include contacts 1009 and 1010 for supplying power from the camera 3 to the lens barrel 2. In this embodiment, the vertical direction (direction of gravity) in Figure 1 is defined as the Y-axis direction, the direction parallel to the optical axis O of the optical system included in the lens barrel 2 is defined as the Z-axis direction, and the direction perpendicular to the Y-axis direction and the Z-axis direction is defined as the X-axis direction.

[0010] Camera 3 includes an image sensor 1106, a display unit 1108, a camera CPU 1100, and a viewfinder 16. The camera CPU 1100 controls a shutter (not shown) to expose the image formed through the lens barrel 2 to the image sensor 1106 for a desired amount of time, thereby enabling photography. The display unit 1108 displays the captured image and a settings screen for changing various settings of the camera system 1. In this embodiment, the display unit 1108 is located on the back of the camera 3 and has a touch panel function. The photographer can check the captured image and input by looking through the viewfinder 16.

[0011] The lens barrel 2 includes an optical system, a zoom operating ring 6, a guide barrel 7, a cam barrel 8, a lens CPU 1000, and an aperture mechanism 11. The optical system comprises a 1st group lens 21, a 2nd group lens 22, a 3rd group lens 23, a 4th group lens 24, a 5th group lens 25, a 6th group lens 26, a 7th group lens 27, an 8th group lens 28, a 9th group lens 29, and a 10th group lens 30. In this embodiment, by moving at least one lens (optical element) included in the optical system, at least one of a tilt effect, which inclins the focal plane with respect to the imaging plane of the image sensor 1106, and a shift effect, which moves the shooting range, can be obtained. Each lens is held by a lens barrel having a cam follower. The cam follower engages with a straight groove parallel to the optical axis O provided in the guide barrel 7 and a groove inclined with respect to the optical axis O provided in the cam barrel 8. When the zoom operating ring 6 rotates, the cam barrel 8 rotates, and the positional relationship of each lens in the Z-axis direction changes. This changes the focal length of the lens barrel 2. The focal length of the lens barrel 2 can be detected by a zoom position detection unit (not shown) that detects the amount of rotation of the zoom operation ring 6. The lens CPU 1000 changes the aperture diameter of the optical system by controlling the aperture mechanism 11.

[0012] The two-group lens 22 is a focusing group (focusing member) that achieves focus by moving in the Z-axis direction. The lens CPU 1000 controls the two-group lens 22 via a vibration actuator 31 using a detection signal from a focus position detection unit (first detection unit) 410, which will be described later, that detects the position of the two-group lens 22.

[0013] In this embodiment, tilt and shift effects can be obtained by moving the 6-group lens 26 (first optical element) and the 8-group lens 28 (second optical element) in a direction perpendicular to the optical axis O. Specifically, a tilt effect can be obtained by moving the 6-group lens 26 and the 8-group lens 28 in opposite directions, and a shift effect can be obtained by moving them in the same direction. The lens CPU 1000 controls the 6-group lens 26 via a drive unit using a signal from a first shift position detection unit (second detection unit) 420, which will be described later, that detects the position of the 6-group lens 26. The lens CPU 1000 also controls the 8-group lens 28 via a drive unit using a signal from a second shift position detection unit (second detection unit) 430, which will be described later, that detects the position of the 8-group lens 28. The drive unit that moves the 6-group lens 26 and the 8-group lens 28 is, for example, a stepping motor or a voice coil motor (VCM). It is also possible to obtain a tilt effect by tilting (rotating) the lens.

[0014] As shown in Figure 1(b), the lens CPU 1000 comprises an acquisition unit 1000a and a control unit 1000b, and controls the operation of each component of the lens barrel 2. The acquisition unit 1000a acquires information indicating the optical state of the optical system. The control unit 1000b uses the information indicating the optical state of the optical system to correct the focus shift caused by the movement of at least one optical element. In this embodiment, the lens CPU 1000 is mounted inside the lens barrel 2, but it may be configured as a separate control device from the lens barrel 2. Alternatively, the camera CPU 1100 may be configured to have the functions of both the acquisition unit 1000a and the control unit 1000b.

[0015] Figure 2 is an electrical configuration diagram of camera system 1. First, we will explain the internal control flow of camera 3.

[0016] The camera CPU 1100 is composed of a microcomputer and controls the operations of each part within the camera 3. Also, when the lens barrel 2 is attached to the camera 3, the camera-side CPU 15 communicates with the lens CPU 1000 via the lens-side communication unit 17 and the camera-side communication unit 18. The information (signals) transmitted from the camera CPU 1100 to the lens CPU 1000 includes the movement amount information of the two-group lens 22 and the defocus information. Further, it includes the attitude information of the camera 3 based on the signals from the camera attitude detection unit 1110 such as an acceleration sensor. Additionally, it includes the subject distance information of the subject indicated by the signal from the TS instruction unit 1109 for the desired subject the photographer wants to focus on and the shooting range information (picture frame) indicating the desired shooting range.

[0017] The information (signals) transmitted from the lens CPU 1000 to the camera CPU 1100 includes optical information such as the imaging magnification of the lens and lens function information such as zoom and anti-shake mounted on the lens barrel 2. Also, it includes the attitude information of the lens barrel 2 based on the signals from the lens attitude detection unit 1008 such as a gyro sensor and an acceleration sensor. Further, it includes the design information of the optical system such as the defocus correction information by lens shift.

[0018] The power switch 1101 is a switch operable by the photographer and is used to start the camera CPU 1100 and supply power to each actuator, sensor, etc. within the camera system 1. The release switch 1102 is a switch operable by the photographer and includes a first-stroke switch SW1 and a second-stroke switch SW2. The signal from the release switch 1102 is input to the camera CPU 1100. The camera CPU 1100 enters the shooting preparation state in response to the input of the ON signal from the first-stroke switch SW1. In the shooting preparation state, the measurement of the subject brightness by the photometry unit 1103 and the focus detection by the focus detection unit 1104 are performed.

[0019] The camera CPU 1100 calculates the aperture value of the aperture mechanism 11 and the exposure amount (shutter time in seconds) of the image sensor 1106 based on the photometering results from the photometering unit 1103. The camera CPU 1100 also determines the amount of movement (including the drive direction) of the two-group lens 22 based on the focus information (defocus amount and defocus direction) of the optical system detected by the focus detection unit 1104. The focus detection unit 1104 detects the focus information of the optical system from information such as phase difference and contrast.

[0020] In this embodiment, as described above, tilt and shift effects can be obtained by moving the 6-group lens 26 and the 8-group lens 28 in a direction perpendicular to the optical axis O. The camera CPU 1100 calculates the tilt drive amount to focus on the desired subject indicated by the TS indicator unit 1109. In this embodiment, the TS indicator unit 1109 is included in the display unit 1108 which has a touch panel function. The camera CPU 1100 also calculates the shift drive amount to change from the current shooting range to the shooting range indicated by the TS indicator unit 1109. The camera CPU 1100 transmits information about the acquired drive amount to the lens CPU 1000. The 6-group lens 26 and the 8-group lens 28 are controlled based on the information about the drive amount described above.

[0021] The number of subjects indicated by the TS indicator unit 1109 may be multiple. Even if subjects at different distances are indicated, it is possible to focus on them as long as they are positioned on the tilted subject surface due to the tilt effect.

[0022] Furthermore, the TS indicator unit 1109 may be provided on the lens barrel 2 instead of the camera 3. Also, the functions of the TS indicator unit 1109 may be assigned to an operation unit already provided in the camera system 1. The TS indicator unit 1109 also includes an operation unit for selecting tilt shooting to obtain a tilt effect or shift shooting to obtain a shift effect.

[0023] When the camera CPU 1100 is set to a predetermined shooting mode, it starts controlling the eccentric drive of the image-stabilizing lens (not shown), i.e., the image stabilization operation. If the lens barrel 2 does not have an image stabilization function, the image stabilization operation will not be performed. In response to the ON signal input from the second stroke switch SW2, the camera CPU 1100 sends an aperture drive command to the lens CPU 1000 and sets the aperture mechanism 11 to a previously acquired aperture value. The camera CPU 1100 also sends an exposure start command to the exposure unit 1105, causing the mirror (not shown) to retract and the shutter (not shown) to open. If the camera 3 is a mirrorless camera, the mirror retraction operation will not be performed. Furthermore, the camera CPU 1100 causes the image sensor 1106 to perform photoelectric conversion of the subject image, i.e., exposure operation.

[0024] The imaging signal from the image sensor 1106 is digitally converted in the signal processing unit within the camera CPU 1100, and further corrected before being output as an image signal. The image signal (data) is stored in the image recording unit 1107, which may contain semiconductor memory such as flash memory, a magnetic disk, or an optical disk.

[0025] The display unit 1108 can display images captured by the image sensor 1106 during shooting. The display unit 1108 can also display images recorded in the image recording unit 1107.

[0026] Next, the control flow inside the lens barrel 2 will be described. The focus operation rotation detection unit 1002 detects the rotation of the focus operation ring 19. The aperture operation rotation detection unit 1011 detects the rotation of the aperture operation ring 20. The zoom operation rotation detection unit 1003 detects the rotation of the zoom operation ring 6. The subject memory unit 1012 stores the spatial position of the subject instructed by the TS instruction unit 1109 within the shooting range. The TS operation detection unit 1001 includes a manual operation unit for obtaining tilt and shift effects, and a sensor for detecting the amount of operation of the manual operation unit. The IS drive unit 1004 includes a drive actuator for the vibration-damping lens that performs vibration damping operation, and a drive circuit for the drive actuator. Note that if the lens barrel 2 does not have a vibration damping function, the above configuration is unnecessary. The focus drive unit (first movement unit) 1006 includes a two-group lens 22 and a vibration actuator 31 that moves the two-group lens 22 in the Z-axis direction according to the amount of movement information. The amount of movement information may be determined based on a signal from the camera CPU 1100, or based on a signal output by operating the focus operation ring 19. Alternatively, it may be determined based on correction information for focus shift that occurs when the 6-group lens 26 and the 8-group lens 28 are shifted in a direction perpendicular to the optical axis O. The electromagnetic aperture drive unit 1005 changes the aperture mechanism 11 to an open state corresponding to the instructed aperture value in response to an instruction from the lens CPU 1000, which has received an aperture drive command from the camera CPU 1100, or in response to an instruction from the imager via the aperture operation ring 20. The TS drive unit 1007 moves the 6-group lens 26 and the 8-group lens 28 in response to an instruction from the lens CPU 1000 based on subject distance, position information, and shooting range information from the camera CPU 1100. The lens barrel 2 has optical characteristics that allow the focus to change even if the subject distance does not change due to the shift operation of the 6-group lens 26 and the 8-group lens 28. The lens CPU 1000 controls the TS drive unit 1007 and the focus drive unit 1006 to operate optimally in accordance with the optical characteristics in order to obtain the desired focus.

[0027] Furthermore, a gyro sensor electrically connected to the lens CPU 1000 is provided inside the lens barrel 2. The gyro sensor detects the angular velocity of the vertical (pitch direction) and horizontal (yaw direction) oscillations of the camera system 1, and outputs the detected values ​​as angular velocity signals to the lens CPU 1000. The lens CPU 1000 electrically or mechanically integrates the angular velocity signals in the pitch and yaw directions from the gyro sensor to calculate the amount of displacement in each direction, namely the pitch oscillation and yaw oscillation (collectively referred to as the angular oscillation).

[0028] The lens CPU 1000 controls the IS drive unit 1004 based on the combined displacement of the angular and parallel runout amounts described above to move the vibration-damping lens (not shown) and perform angular runout correction and parallel runout correction. Note that if the lens barrel 2 does not have a vibration-damping function, the above configuration is unnecessary.

[0029] The principle of Scheinproof will be explained below with reference to Figure 3. Figure 3(a) shows the range of focus when the optical axis of the optical system 1201 is not tilted with respect to the image sensor 1200. Figure 3(b) shows the range of focus when the optical axis of the optical system 1201 is tilted with respect to the image sensor 1200. The principle of Scheinproof states that, as shown in Figure 3(b), when the image sensor 1200 and the principal surface 1203 of the optical system intersect at intersection 1204, the subject surface 1202 that is in focus also passes through intersection 1204. Therefore, when the optical axis of the optical system 1201 is tilted with respect to the image sensor 1200, the range of focus on the subject is determined by the principle of Scheinproof. If the subject to be photographed has depth, by tilting the subject surface 1202 to follow that depth, it is possible to focus on the subject from the foreground to the background. On the other hand, by tilting the main surface 1203 of the optical system 1201 in the opposite direction to the inclination of the subject with depth, it is also possible to intersect the subject surface 1202 with respect to the depth direction of the subject at an angle close to a right angle. In this case, the range of focus can be made extremely narrow, so it is possible to obtain a diorama-like image.

[0030] In this embodiment, as shown in Figure 3(c), the tilt θobj of the subject plane 1202 is generated without tilting the imaging plane 1200 by the amount of image tilt θimg by utilizing the image drift caused by the eccentricity of the optical system 1201. However, if the tilt θobj of the subject plane 1202 is generated solely by the optical system 1201, the amount of eccentricity of the optical system 1201 increases, resulting in a larger composition shift. Therefore, it is preferable to eccentricate a lens that is designed to minimize aberration fluctuations during eccentricity. In this embodiment, in order to change the tilt effect, the 6-group lens 26 that generates the tilt of the subject plane and the 8-group lens 28 that minimizes aberration fluctuations during eccentricity are eccentrically operated.

[0031] The following describes how to correct the focus shift that occurs when the 6-group lens 26 and the 8-group lens 28 are moved in a direction perpendicular to the optical axis O.

[0032] Figure 4 shows the configuration necessary for correcting focus errors in this embodiment. The lens CPU 1000 includes a focus control unit 400, a shift control unit 401, and an aperture control unit 404. The shift control unit 401 includes a first shift control unit 402 and a second shift control unit 403.

[0033] The focus drive unit 1006 moves the two-group lens 22 in response to instructions from the focus control unit 400. The focus position detection unit 410 detects the current position of the two-group lens 22 and outputs the detection result to the focus control unit 400.

[0034] The first shift drive unit (second movement unit) 421 moves the 6-group lens 26 in response to instructions from the first shift control unit 402. The first shift position detection unit (second detection unit) 420 detects the current position of the 6-group lens 26 and outputs the detection result to the first shift control unit 402.

[0035] The second shift drive unit (second movement unit) 431 moves the 8-group lens 28 in response to instructions from the second shift control unit 403. The second shift position detection unit (second detection unit) 430 detects the current position of the 8-group lens 28 and outputs the detection result to the second shift control unit 403.

[0036] The first shift drive unit 421 and the second shift drive unit 431 are included in the TS drive unit 1007.

[0037] The aperture mechanism 11 includes an electromagnetic aperture drive unit 1005. The electromagnetic aperture drive unit 1005 drives the aperture mechanism 11 in response to instructions from the aperture control unit 404, changing it to an aperture state corresponding to the instructed aperture value. The lens CPU 1000 can acquire the aperture value of the aperture mechanism 11 (information related to the aperture mechanism 11) as information indicating the optical state of the optical system.

[0038] The lens data storage unit 440 stores the optical system design information, namely the first focus shift correction information 441 and the second focus shift correction information 442. The first focus shift correction information 441 includes a table showing the focus correction amount for each position of the second lens group 22, corresponding to the shift amount in the direction perpendicular to the optical axis O of the sixth lens group 26. The second focus shift correction information 442 includes a table showing the focus correction amount for each position of the second lens group 22, corresponding to the shift amount in the direction perpendicular to the optical axis O of the eighth lens group 28. The focus correction amount is 0 when the shift amount is 0. The focus correction amount and shift amount may be relative or absolute values. The focus correction amount may be the absolute value or relative value of the focus shift amount. The first focus shift correction information 441 and the second focus shift correction information 442 may include tables or information derived from mathematical formulas, etc. By using the first focus shift correction information 441 and the second focus shift correction information, it is possible to correct focus shifts that change according to the focus position, thus enabling highly accurate focus shift correction.

[0039] In this embodiment, the table is represented in graph form, but it may also be in tabular form. Furthermore, the data in the table may be discrete values, and values ​​between discrete values ​​may be interpolated. Each focus shift correction information may include a table for each piece of information indicating the position of the 2-group lens 22, for example, a table for each subject distance. Alternatively, information indicating the positions of the 6-group lens 26 and the 8-group lens 28 may be used instead of the shift amount.

[0040] Furthermore, the lens data storage unit 440 may store focus shift correction information corresponding to the image height position to be focused, and focus shift correction information corresponding to aperture information.

[0041] Figure 6 is a flowchart showing the focus correction method of this embodiment.

[0042] In step S501, the lens CPU 1000 uses the output signal from the focus position detection unit 410 to obtain the position of the 2-group lens 22 when both the 6-group lens 26 and the 8-group lens 28, which are information indicating the optical state of the optical system, are located in the center (the shift amount is 0).

[0043] In step S502, the lens CPU 1000 uses the position of the two-group lens 22 acquired in step S501 to select a table to use from among multiple tables included in the first focus shift correction information 441 (second focus shift correction information 442).

[0044] In step S503, the lens CPU 2000 retrieves the previous focus correction amount A. For example, before shifting the 6-group lens 26 and the 8-group lens 28, the focus correction amount A is 0.

[0045] In step S504, the lens CPU 1000 determines whether the two-group lens 22 is moving. If it is determined to be moving, the process proceeds to step S505; otherwise, it proceeds to step S508. For example, if the subject to be photographed changes and the focus position is changed, it is necessary to change the table used, but by performing the processing in this step, the focus shift can be corrected with high accuracy.

[0046] In step S505, the lens CPU 1000 uses the output signal from the focus position detection unit 410 to acquire the amount of movement F of the two-group lens 22, which is information indicating the optical state of the optical system.

[0047] In step S506, the lens CPU 1000 updates the focus correction amount A to the sum of the focus correction amount A obtained in step S503 and the movement amount F obtained in step S505.

[0048] In step S507, the lens CPU 1000 uses the focus correction amount A and the shift amount of the 6-group lens 26 (8-group lens 28) to select a table to use from among multiple tables included in the first focus shift correction information 441 (second focus shift correction information 442).

[0049] In step S508, the lens CPU 1000 determines whether the 6-group lens 26 (8-group lens 28) is moving. If it is determined that it is moving, the process proceeds to step S509; otherwise, this flow terminates.

[0050] In step S509, the lens CPU 1000 uses the output signal of the first shift position detection unit 420 (second shift position detection unit) to acquire the shift amount of the 6-group lens 26 (8-group lens 28), which is information indicating the optical state of the optical system.

[0051] In step S510, the lens CPU 1000 uses the table selected in step S507 to obtain the focus correction amount B1 (focus correction amount B2) corresponding to the shift amount of the 6-group lens 26 (8-group lens 28) acquired in step S509.

[0052] In step S511, the lens CPU 1000 determines whether the absolute value of the value B1+B2-A is greater than the tolerance value. The tolerance value is, for example, the smallest unit that the focus drive unit 1006 can drive, or the tolerance depth of field. The depth of field is determined, for example, from the aperture value or the tolerance circle of confusion. If it is determined that the absolute value of the value B1+B2-A is greater than the tolerance value, the process proceeds to step S512. If it is determined that the absolute value of the value B1+B2-A is greater than the tolerance value, the process returns to step S503. Note that if the absolute value of the value B1+B2-A is equal to the tolerance value, it is possible to arbitrarily set which step to proceed to.

[0053] In step S512, the lens CPU 1000 instructs the focus control unit 400 to move the two-group lens 22 by a value of B1 + B2 - A via the focus drive unit 1006.

[0054] In step S513, the lens CPU 1000 updates the focus correction amount A to the value B1 + B2 - A.

[0055] Here, instead of the position and amount of movement of the second lens group 22, information indicating the position of the second lens group 22 may be used. Information indicating the position of the second lens group 22 may be obtained, for example, using the input signal to the focus drive unit 1006, or from subject distance information, or using the signal from the focus operation rotation detection unit 1002. Also, instead of the amount of shift of the sixth lens group 26, information indicating the position of the sixth lens group 26 may be used. Information indicating the position of the sixth lens group 26 may be obtained, for example, using the input signal to the first shift drive unit 421, or using the signals from the TS operation detection unit 1001 or the TS instruction unit 1109. Also, instead of the amount of shift of the eighth lens group 28, information indicating the position of the eighth lens group 28 may be used. Information indicating the position of the eighth lens group 28 may be obtained, for example, using the input signal to the second shift drive unit 431, or using the signals from the TS operation detection unit 1001 or the TS instruction unit 1109. Furthermore, the information indicating each position may be obtained using velocity and acceleration information. Alternatively, the focus correction amount may be obtained using the previously acquired shift amounts of the 6-group lens 26 and 8-group lens 28, and after moving the 2-group lens 22, the 6-group lens 26 and 8-group lens 28 may be shifted. Alternatively, the 6-group lens 26, 8-group lens 28, and 2-group lens 22 may be moved simultaneously. Furthermore, in addition to correcting the focus shift by moving the 2-group lens 22, the focus shift may also be corrected by changing the depth of field using the aperture mechanism 11. Also, the number of shift units is not limited to two; there may be one or three or more. In addition, each data may be stored as an absolute value or as a relative value before and after the change. Furthermore, focus shift correction may be performed based on focus information from the focus detection unit 1104. In addition, the optical elements may be moved in a direction perpendicular to the optical axis O by manual operation.

[0056] As described above, in this embodiment, it is possible to correct the focus shift that occurs when an optical element is moved in a direction perpendicular to the optical axis O, based on information indicating the optical state of the optical system. Furthermore, by using multiple focus shift correction information corresponding to the focus position (subject distance), it is possible to correct the focus shift with even higher precision. In addition, since the focus shift can be corrected only by the position and movement of the optical element, it is possible to perform focus shift correction control without recognizing the subject. Moreover, since it is possible to perform control with little time lag and good tracking performance, it is possible to perform tilt shooting and shift shooting with little focus shift even when shooting video.Therefore, according to the configuration of this embodiment, it is possible to maintain high precision in focus even when obtaining tilt effects or shift effects. [Second Embodiment] The basic configuration of the camera system in this embodiment is the same as that of the camera system 1 in the first embodiment. In this embodiment, the configurations that differ from the first embodiment will be described, and the configurations that are common to the first embodiment will not be described.

[0057] Figure 7 shows the configuration necessary for correcting focus misalignment in this embodiment. The lens data storage unit 440 stores tilt focus misalignment correction information 443 and shift focus misalignment correction information 444, which are optical system design information. The tilt focus misalignment correction information 443 includes a table showing the amount of focus correction according to the amount of shift in the direction perpendicular to the optical axis O of the 6-group lens 26 in tilt photography, as shown in Figure 8(a). The shift focus misalignment correction information 444 includes a table showing the amount of focus correction according to the amount of shift in the direction perpendicular to the optical axis O of the 6-group lens 26 in shift photography, as shown in Figure 8(b). In tilt photography and shift photography, the correspondence between the shift amounts of the 6-group lens 26 and the 8-group lens 28 is determined, so if the shift amount of the 6-group lens 26 can be obtained, the amount of focus correction can be obtained. Furthermore, the tilt focus shift correction information 443 and the shift focus shift correction information 444 may store a table showing the amount of focus correction corresponding to the amount of shift in a direction perpendicular to the optical axis O of the 8-group lens 28.

[0058] Figure 9 is a flowchart showing the focus correction method of this embodiment.

[0059] Since the process in step S601 is the same as the process in step S501 in Figure 7, a detailed explanation will be omitted.

[0060] In step S602, the lens CPU 1000 uses the position of the two-group lens 22 acquired in step S501 to select a table to use from among multiple tables included in the tilt focus shift correction information 443 (shift focus shift correction information 444).

[0061] Since the processes in steps S603 to S606 are the same as those in steps S503 to S506 in Figure 7, a detailed explanation will be omitted.

[0062] In step S607, the lens CPU 1000 uses the focus correction amount A and the shift amount of the 6-group lens 26 to select a table to use from among multiple tables included in the tilt focus shift correction information 443 (shift focus shift correction information 444).

[0063] In step S608, the lens CPU 1000 determines whether the 6-group lens 26 is moving. If it is determined that it is moving, the process proceeds to step S609; otherwise, this flow terminates.

[0064] In step S609, the lens CPU 1000 uses the output signal of the first shift position detection unit 420 to acquire the shift amount of the 6-group lens 26, which is information indicating the optical state of the optical system.

[0065] In step S610, the lens CPU 1000 uses information from the TS operation detection unit 1001 and the TS instruction unit 1109 to determine whether tilt shooting is in progress. If it is determined that tilt shooting is in progress, the process proceeds to step S611; otherwise, if it is determined that shift shooting is in progress, the process proceeds to step S612.

[0066] In step S611, the lens CPU 1000 obtains a focus correction amount B corresponding to the shift amount of the 6-group lens 26 obtained in step S609, using a table selected from multiple tables included in the tilt focus shift correction information 443 in step S607.

[0067] In step S612, the lens CPU 1000 obtains a focus correction amount B corresponding to the shift amount of the 6-group lens 26 obtained in step S609, using a table selected from multiple tables included in the shift focus correction information 444 in step S607.

[0068] In step S613, the lens CPU 1000 determines whether the absolute value of value BA is greater than the allowable value. If it is determined that the absolute value of value BA is greater than the allowable value, the process proceeds to step S614. If it is determined that the absolute value of value BA is less than the allowable value, the process returns to step S603. Note that if the absolute value of value BA is equal to the allowable value, the process can be arbitrarily configured to proceed to either step.

[0069] In step S614, the lens CPU 1000 instructs the focus control unit 400 to move the two-group lens 22 by a value BA via the focus drive unit 1006.

[0070] In step S615, the lens CPU 1000 updates the focus correction amount A to the value BA.

[0071] As described above, in this embodiment, by determining whether tilt shooting or shift shooting is in progress, it is possible to correct the focus shift using information from one of the two optical elements that are moved to acquire at least one of the tilt effect and the shift effect. [Other examples] The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0072] This embodiment includes the following configurations and methods. (Composition 1) A control device used in a camera system having an imaging device equipped with an image sensor, and a lens device comprising an optical system including at least one optical member for changing at least one of a tilt effect that inclins the focal plane with respect to the imaging plane of the image sensor and a shift effect that moves the shooting range, and a focusing member for focusing, An acquisition unit that acquires information indicating the optical state of the optical system, A control device characterized by having a control unit that corrects a focus shift caused by the movement of at least one optical element using information indicating the optical state of the optical system. (Configuration 2) The acquisition unit acquires the design information of the optical system, The control device according to configuration 1, characterized in that the control unit corrects the focus misalignment using information indicating the optical state of the optical system and design information of the optical system. (Composition 3) The control device according to configuration 2, characterized in that the design information of the optical system includes information for correcting focus deviations corresponding to information indicating the position of the focusing member and information indicating the position of at least one optical member. (Composition 4) The control device according to any one of configurations 1 to 3, characterized in that the information indicating the optical state of the optical system includes information indicating the position of the focusing member and information indicating the position of at least one optical member. (Composition 5) The lens device comprises a first detection unit for detecting the position of the focusing member and a first moving unit for moving the focusing member along the optical axis of the optical system. The control device according to configuration 4, characterized in that the information indicating the position of the focus member is at least one of the output signal from the first detection unit, the input signal to the first moving unit, and the subject distance. (Composition 6) The lens device comprises a second detection unit for detecting the position of the at least one optical element, and a second moving unit for moving the at least one optical element. The control device according to configuration 4 or 5, characterized in that the information indicating the position of the at least one optical element includes at least one of the output signal from the second detection unit and the input signal to the second movement unit. (Composition 7) The control device according to any one of configurations 1 to 6, characterized in that the control unit corrects the focus misalignment by controlling the focus member. (Composition 8) The lens device includes an aperture mechanism that changes the aperture diameter of the optical system, The information indicating the optical state of the optical system includes information regarding the aperture mechanism, The control device according to any one of configurations 1 to 7, characterized in that the control unit corrects the focus error by controlling the aperture mechanism. (Composition 9) A control device described in any one of configurations 1 to 8, A lens device characterized by having an optical system that includes at least one optical element for changing at least one of a tilt effect, which inclins the focal plane with respect to the imaging plane of the image sensor, and a shift effect, which moves the shooting range, and a focusing element for focusing. (Composition 10) The lens device according to configuration 9, characterized in that the at least one optical member comprises a first optical member and a second optical member. (Composition 11) The lens device according to configuration 9 or 10, characterized in that the at least one optical member changes at least one of the tilt effect and the shift effect by moving in a direction perpendicular to the optical axis of the optical system. (Composition 12) A control device described in any one of configurations 1 to 8, An imaging device characterized by having an image sensor. (Composition 13) A control device described in any one of configurations 1 to 8, Image sensor and A camera system characterized by having an optical system that includes at least one optical element for changing at least one of a tilt effect that inclines the focal plane with respect to the imaging plane of the image sensor and a shift effect that moves the shooting range, and a focusing element for focusing. (Method 1) A control method for controlling a camera system having an imaging device equipped with an image sensor, and a lens device having an optical system including at least one optical member for changing at least one of a tilt effect that inclins the focal plane with respect to the imaging plane of the image sensor and a shift effect that moves the shooting range, and a focusing member for focusing, A step of acquiring information indicating the optical state of the optical system, A control method characterized by comprising the step of correcting a focus shift caused by the movement of at least one optical element using information indicating the optical state of the optical system. (Composition 14) A program characterized by causing a computer to execute the control method described in Method 1.

[0073] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its gist. [Explanation of symbols]

[0074] 1 Camera System 2. Lens barrel (lens device) 3. Camera (imaging device) 22. 2-group lens (focusing element) 26. 6-group lens (optical components) 28. 8-group lens (optical components) 1000 Lens CPU (Control Unit) 1000a Acquisition Department 1000b Control Unit 1100 Camera CPU (Control Unit) 1106 Image sensor

Claims

1. A control device used in a lens device having an optical system including a first optical member that is movable when changing at least one of the inclination of a focal plane relative to an imaging plane and the position of a shooting range, and a second optical member that is movable when focusing, comprising: A control unit that controls movement of the first and second optical members; an acquisition unit that acquires first information regarding an optical state of the optical system, The control device, characterized in that the control unit corrects focus deviation caused by movement of the first optical member by moving the second optical member based on the first information.

2. The control device described in Claim 1, characterized in that the control unit corrects the focus shift by moving the second optical element based on the first information and second information regarding design values ​​of the optical system.

3. 3. The control device according to claim 2, wherein the second information includes information indicating a relationship between an amount of movement of the first optical member and an amount of movement of the second optical member required to correct the focus shift.

4. The control device according to claim 1 , wherein the first information includes information regarding a position of at least one of the first and second optical members.

5. the lens device includes a first detection unit that detects a position of the second optical member and a first movement unit that moves the second optical member; 2 . The control device according to claim 1 , wherein the first information includes at least one of an output signal from the first detection unit, an input signal to the first movement unit, and a subject distance.

6. the lens device includes a second detection unit that detects a position of the first optical member and a second movement unit that moves the first optical member; 2. The control device according to claim 1, wherein the first information includes at least one of an output signal from the second detection portion and an input signal to the second movement portion.

7. 2 . The control device according to claim 1 , wherein the control unit corrects a focus error caused by the movement of the first optical member so that the focus state of the optical system approaches a focus state immediately before the movement.

8. A control device for use in a lens device having an optical system including a first optical member that is movable when changing at least one of the inclination of a focal plane relative to an imaging plane and the position of a shooting range, and an aperture mechanism that is capable of changing an aperture diameter, comprising: a control unit that controls the movement of the first optical member and the change in the aperture diameter; an acquisition unit that acquires first information regarding an optical state of the optical system, The control device is characterized in that the control unit corrects focus deviation caused by movement of the first optical member by changing the aperture diameter based on the first information.

9. The control device described in Claim 8, characterized in that the first information includes information regarding the aperture value of the aperture mechanism.

10. A lens device comprising a control device described in any one of claims 1 to 9 and the optical system.

11. An imaging device comprising: the control device according to claim 1 ; and an imaging element including the imaging surface.

12. A camera system comprising: the lens apparatus according to claim 10; and an image sensor including the image pickup surface.

13. A control method for controlling a lens device having an optical system including a first optical member that is movable when changing at least one of an inclination of a focal plane relative to an imaging plane and a position of a shooting range, and a second optical member that is movable when focusing, comprising: a control step of controlling movements of the first and second optical members; and acquiring first information regarding an optical state of the optical system, The control method, wherein the control step corrects focus deviation caused by movement of the first optical member by moving the second optical member based on the first information.

14. A program causing a computer to execute the control method according to claim 13.

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