Control device, imaging device, lens device, camera system, method, and medium

Abstract

The present invention provides a control device, an imaging device, a lens device, a camera system, a method, and a medium. The control device includes: a first acquisition unit configured to acquire information related to an image shift sensitivity with respect to decentration of an image stabilization optical system, the information being associated with an image point position of an imaging optical system, the imaging optical system including the image stabilization optical system configured to perform image stabilization; and a second acquisition unit configured to acquire a first image stabilization driving amount of the image stabilization optical system during image stabilization. The second acquisition unit acquires the first image stabilization driving amount associated with the predetermined image point position by using the information related to the image shift sensitivity associated with the predetermined image point position.

Description

Technical Field

[0001] The present disclosure relates to a control device, a imaging device, a lens device, a camera system, a control method, and a storage medium that respectively control image stabilization. Background Art

[0002] When using an optical system that uses a central projection method, the movement of image points on the imaging plane is different between the central part and the peripheral part of the image, and the movement of image points is caused by camera shake. As Figure 18A shown, the amount of movement of image points in the peripheral part of the image is greater than the amount of movement of image points in the central part of the image. Therefore, as Figure 18B shown, even when image stabilization is performed, the movement amplitude of image points in the peripheral part of the image is still greater than that of image points in the central part of the image. Japanese Patent Application Laid-Open ("JP") No. 2018-173632 discloses an imaging device that reduces image blurring at the image point position in the peripheral part of the image in consideration of the difference between the amount of image blurring in the central part of the image and the amount of image blurring at a predetermined image point position caused by the central projection method.

[0003] In JP 2018-173632, the imaging device calculates the amount of image stabilization for reducing image blurring at a predetermined image point position in consideration of the image shift sensitivity with respect to the tilt of the optical system, and the image shift sensitivity depends on the image height of the subject image. However, in the case of performing image stabilization by a lens shift type image stabilization mechanism, the image shift sensitivity with respect to the decentration of the image stabilization optical system has characteristics different from those of the image shift sensitivity with respect to the tilt of the optical system. Therefore, in the case of performing image stabilization on image blurring at a predetermined image point position by using an image stabilization optical system, if the amount of image stabilization is calculated without considering the image shift sensitivity with respect to the decentration of the image stabilization optical system for the image point position, the image stabilization may be insufficient or excessive. Summary of the Invention

[0004] The present disclosure provides a control device, an imaging device, a lens device, a camera system, a control method, and a storage medium that can each easily and satisfactorily reduce image blurring at a predetermined image point position including the optical axis center.

[0005] A control device according to an aspect of an embodiment of the present disclosure includes: a first acquisition unit configured to acquire information related to an image shift sensitivity with respect to decentration of an image stabilization optical system, the information being associated with an image point position of an imaging optical system, the imaging optical system including the image stabilization optical system configured to perform image stabilization; and a second acquisition unit configured to acquire a first image stabilization drive amount of the image stabilization optical system during image stabilization. The second acquisition unit acquires the first image stabilization drive amount associated with the predetermined image point position by using the information related to the image shift sensitivity associated with the predetermined image point position.

[0006] An imaging device and a lens device each including the above control device also constitute other aspects of an embodiment of the present disclosure.

[0007] A camera system according to an aspect of an embodiment of the present disclosure includes: a first acquisition unit configured to acquire information related to an image shift sensitivity with respect to decentration of an image stabilization optical system, the information being associated with an image point position of an imaging optical system, the imaging optical system including the image stabilization optical system configured to perform image stabilization; and a second acquisition unit configured to acquire a first image stabilization drive amount of the image stabilization optical system during image stabilization. The second acquisition unit includes: a lens device configured to acquire the first image stabilization drive amount associated with the predetermined image point position by using the information related to the image shift sensitivity associated with the predetermined image point position; a third acquisition unit configured to acquire information capable of being used to acquire a movement amount of the predetermined image point position for obtaining tilt of the imaging optical system; and a fourth acquisition unit configured to acquire a second image stabilization drive amount of an image stabilization unit during image stabilization, the image stabilization unit being configured to perform image stabilization. The fourth acquisition unit includes: an imaging device configured to acquire the second image stabilization drive amount associated with the predetermined image point position by using the information capable of being used to acquire a movement amount of the predetermined image point position for obtaining tilt of the imaging optical system.

[0008] A control method according to an aspect of an embodiment of the present disclosure is a control method for acquiring an image stabilization drive amount of an image stabilization optical system during image stabilization, the image stabilization optical system being configured to perform image stabilization. The control method includes: acquiring information related to an image shift sensitivity with respect to decentration of the image stabilization optical system, the information being associated with an image point position of an imaging optical system; and acquiring an image stabilization drive amount of the image stabilization optical system associated with the predetermined image point position by using the information related to the image shift sensitivity associated with the predetermined image point position.

[0009] A non - transitory computer - readable storage medium according to one aspect of an embodiment of the present disclosure stores a computer program that causes a computer to execute the above - described control method.

[0010] Other features of the present invention will become clear from the following description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic configuration diagram showing a camera system according to a first embodiment.

[0012] Figure 2 is a flowchart showing a control method for obtaining an image - stabilization driving amount according to a first embodiment.

[0013] Figure 3A shows the relationship between the image height in the image - point movement direction and the tilt - image - shift sensitivity of the central portion of an image when the imaging optical system according to the first embodiment is tilted. Figure 3B shows the relationship between the image height in the direction orthogonal to the image - point movement direction and the tilt - image - shift sensitivity of the central portion of an image when the imaging optical system according to the first embodiment is tilted.

[0014] Figure 4 is a diagram showing a comparison between the image - point movement at a predetermined image - point position and the image - point movement of the central portion of an image when rotational jitter about the Y - axis occurs according to a first embodiment.

[0015] Figure 5A is a diagram showing the image - point position on the imaging plane. Figure 5B is a diagram showing an image - stabilization coefficient table including image - stabilization coefficient information associated with the image - point position.

[0016] Figure 6A shows the relationship between the image height in the centrifugal direction and the centrifugal - image - shift sensitivity of the central portion of an image when the image - stabilization optical system according to the first embodiment is centrifuged. Figure 6B shows the relationship between the image height in the direction orthogonal to the centrifugal direction and the centrifugal - image - shift sensitivity of the central portion of an image when the image - stabilization optical system according to the first embodiment is centrifuged.

[0017] Figure 7 is a diagram showing a comparison between the image - point movement at a predetermined image - point position and the image - point movement of the central portion of an image when the image - stabilization optical system according to the first embodiment is centrifuged.

[0018] Figure 8It is a diagram showing the arrows according to the first embodiment, where each arrow indicates the ratio and direction of the amount of image point movement of the remaining blur residue at the image point after reducing image blur at a predetermined image point position by OIS.

[0019] Figure 9 It is a structural diagram showing the lens microcomputer and the camera microcomputer according to the second embodiment.

[0020] Figure 10A It shows the process from the state of turning on the power of the imaging system to the state where the image stabilization function is turned on and the imaging device becomes the imaging standby state. Figure 10B It shows the process for stabilizing the rotational shake during imaging.

[0021] Figure 11 It is a cross-sectional view showing the optical system according to Example 1 at the wide-angle end focused on an object at infinity.

[0022] Figure 12 It is an aberration diagram in the state where the optical system according to Example 1 at the wide-angle end is focused on an object at infinity.

[0023] Figure 13 It is a cross-sectional view showing the optical system according to Example 2 at the wide-angle end focused on an object at infinity.

[0024] Figure 14 It is an aberration diagram in the state where the optical system according to Example 2 at the wide-angle end is focused on an object at infinity.

[0025] Figure 15 It is a cross-sectional view showing the optical system according to Example 3 focused on an object at infinity.

[0026] Figure 16 It is an aberration diagram in the state where the optical system according to Example 3 is focused on an object at infinity.

[0027] Figures 17A to 17C It is a diagram showing the light ray trajectories at the d-line of each viewing angle of the chief ray incident from the object plane of the optical system according to Example 1.

[0028] Figure 18A It shows the ratio and direction of the amount of image point movement at each image point on the subject image in the case where image blur caused by rotational shake occurs in the -X axis direction in the central part of the image. Figure 18B It shows each indicating that in the case of reducing Figure 18A the image blur in the central part of the image by the lens shift type image stabilization mechanism, the ratio and direction of the amount of image point movement of the remaining blur residue at the image point. Detailed Description

[0029] Embodiments of the present invention will now be described with reference to the accompanying drawings. Corresponding elements in the drawings will be designated by the same reference numerals, and their description will be omitted.

[0030] In the following description, in a three-dimensional orthogonal coordinate system of the X-axis direction, the Y-axis direction, and the Z-axis direction, the long side direction of the imaging plane is the X-axis direction, the short side direction of the imaging plane is the Y-axis direction, and the optical axis direction of the imaging optical system is the Z-axis direction.

[0031] First Embodiment

[0032] Figure 1 FIG. is a schematic configuration diagram showing an imaging system (camera system) 1 of the present embodiment. The imaging system 1 includes a lens device 100 and an imaging device 200. The lens device 100 includes an imaging optical system 101, a lens microcomputer 102, an OIS encoder 103, an OIS driver 104, an OIS actuator 105, and a lens memory (memory unit) 106. OIS is image stabilization performed by moving an image stabilization optical system 1014 included in the imaging optical system 101. The imaging device 200 includes an image sensor 201, a camera microcomputer 202, a display operation unit 203, and a recording medium 204. The imaging device 200 also includes a gyro sensor 205, an acceleration sensor 206, an IIS encoder 208, an IIS driver 209, an IIS actuator 210, and a camera memory (memory unit) 211. IIS is image stabilization performed by moving the image sensor 201. The lens microcomputer 102 and the camera microcomputer 202 can be configured as control devices separate from the lens device 100 and the imaging device 200, respectively.

[0033] The imaging optical system 101 includes a focusing optical system 1011, a zoom optical system 1012, an aperture 1013, and an image stabilization optical system 1014. The imaging optical system 101 guides light from a subject at a focus position in a set viewing angle so that a subject image is formed on the imaging plane of the image sensor 201. The focusing optical system 1011 performs focusing. The zoom optical system 1012 changes the magnification to change the imaging viewing angle. The aperture 1013 adjusts the amount of light captured from the subject. The image stabilization optical system 1014 is decentered from the optical axis of the imaging optical system 101 so that image blur occurring when shooting a still image or a moving image is reduced.

[0034] The lens microcomputer 102 controls the image stabilization optical system 1014. Specifically, the lens microcomputer 102 determines the OIS driving amount of the OIS actuator 105 by using the image stabilization driving amount output from the camera microcomputer 202 and the position signal output from the OIS encoder 103, and the OIS encoder 103 is configured to detect the position of the image stabilization optical system 1014. The lens microcomputer 102 determines the OIS driving amount such that the OIS driving amount does not exceed the movable range of the OIS actuator 105. When the OIS actuator 105 receives the OIS driving amount signal output from the OIS driver 104, the OIS actuator 105 decenters the image stabilization optical system 1014 with respect to the optical axis of the imaging optical system 101 by moving the image stabilization optical system 1014 in a direction including a component in a direction orthogonal to the Z-axis direction, and performs image stabilization.

[0035] The lens memory 106 stores optical design information of the imaging optical system 101, such as focal length information and object distance information. The optical design information includes information on the tilting image shift sensitivity for each image height of the imaging optical system 101 (information on the tilting image shift sensitivity of the imaging optical system 101, which is associated with the image point position of the imaging optical system 101). The optical design information further includes information on the decentering image shift sensitivity for each image height of the image stabilization optical system 1014 (information on the decentering image shift sensitivity of the image stabilization optical system 1014, which is associated with the image point position of the imaging optical system 101). In the case where rotational jitter occurs in the imaging system 1 and the XY plane orthogonal to the optical axis is tilted with respect to the optical axis, using the information on the tilting image shift sensitivity and the information on the decentering image shift sensitivity enables good reduction of image blur at a predetermined image point position of the imaging optical system 101. The camera memory 211 may store the optical design information of the imaging optical system 101, which includes the information on the tilting image shift sensitivity and the information on the decentering image shift sensitivity. Alternatively, both the lens memory 106 and the camera memory 211 may store the optical design information of the imaging optical system 101, which includes the information on the tilting image shift sensitivity and the information on the decentering image shift sensitivity.

[0036] The image sensor 201 is a charge-coupled device (CCD) image sensor, a complementary metal oxide semiconductor (CMOS) image sensor, or other image sensors. The image sensor 201 converts the subject image formed on the imaging plane of the image sensor 201 by the imaging optical system 101 into an electrical signal, and outputs it as an image signal. The image signal as an analog signal is converted into a digital signal by an A / D converter (not shown) and output.

[0037] The camera microcomputer 202 controls the entire imaging system 1. For example, the camera microcomputer 202 reads out an image signal as image data from the image sensor 201. After that, the camera microcomputer 202 performs the following processing on the image data, such as image processing based on optical design information, processing for displaying the image data on the display operation unit 203, and processing for storing the image data on the recording medium 204. The camera microcomputer 202 sends instructions such as instructions for focusing, magnification change, and aperture adjustment of the imaging optical system 101 to the lens microcomputer 102. Some settings related to the above processing can be changed by an operation unit such as the display operation unit 203 and buttons (not shown).

[0038] The camera microcomputer 202 obtains an image stabilization drive amount (the image stabilization drive amount of the image stabilization optical system 1014 during image stabilization) according to Figure 2 the flow. Figure 2 FIG. is a flowchart of a control method for obtaining an image stabilization drive amount, and this control method is performed by the camera microcomputer 202. In the first acquisition step S1, the camera microcomputer 202 serves as a first acquisition unit and acquires information related to the image shift sensitivity with respect to the eccentricity of the image stabilization optical system 1014, and this information is associated with the image point position of the imaging optical system 101. In the second acquisition step S2, the camera microcomputer 202 serves as a second acquisition unit and acquires a drive amount associated with a predetermined image point position by using the information related to the image shift sensitivity with respect to the eccentricity of the image stabilization optical system 1014, and this information is associated with the predetermined image point position. The camera microcomputer 202 can calculate the image stabilization drive amount, or can obtain the image stabilization drive amount from a table stored in a server, a memory, etc. In this embodiment, the camera microcomputer 202 serves as the first acquisition unit and the second acquisition unit, but the lens microcomputer 102 can serve as the first acquisition unit and the second acquisition unit.

[0039] The gyro sensor 205 outputs information about the angular velocity of the imaging system 1 as a motion detection signal. The acceleration sensor 206 outputs information about the amount of movement of the imaging system 1 in the translation direction as a motion detection signal. In response to receiving the motion detection signals sent from the respective sensors, the camera microcomputer 202 sends the image stabilization drive amount to the IIS control unit 207 in the lens microcomputer 102 or the camera microcomputer 202, and performs image stabilization on the subject image blurred due to the shake of the imaging system 1. In image stabilization, OIS or IIS can be performed, or the share of image stabilization can be determined (for example, 50% of image stabilization is performed by OIS, and 50% of image stabilization is performed by IIS), and both OIS and IIS can be performed.

[0040] The IIS control unit 207 controls the image sensor 201. Specifically, the IIS control unit 207 determines the IIS drive amount of the IIS actuator 210 by using the image stabilization drive amount transmitted from the camera microcomputer 202 and the position signal output from the IIS encoder 208, which is configured to detect the position of the image sensor 201. The IIS drive amount is determined such that the IIS drive amount does not exceed the movable range of the IIS actuator 210. In response to receiving the IIS drive amount signal from the IIS driver 209, the IIS actuator 210 decenters the image sensor with respect to the optical axis of the imaging optical system 101 by moving the image sensor in a direction including a component in a direction orthogonal to the Z-axis direction, and performs image stabilization. That is, the IIS actuator 210 serves as one of the image stabilization units for reducing image blurring.

[0041] The lens device 100 may include a gyro sensor 107 or an acceleration sensor 108. In this case, when OIS is to be performed, the lens microcomputer 102 may determine the OIS drive amount by using the image stabilization drive amount obtained by using the motion detection signal output from these sensors and the position signal output from the OIS encoder 103.

[0042] Hereinafter, the processing in OIS in the case of reducing image blurring at a predetermined image point position will be described. When the gyro sensor 205 or the acceleration sensor 206 detects the shake of the imaging system 1, each sensor outputs a motion detection signal (information about the shake) to the camera microcomputer 202. The camera microcomputer 202 obtains the image stabilization drive amount by using the information about the tilt image shift sensitivity, the information about the decentering image shift sensitivity, the information about the image stabilization position on the imaging plane, and the motion detection signal stored in the lens memory 106. The camera microcomputer 202 sends the obtained image stabilization drive amount to the lens microcomputer 102 or the IIS control unit 207.

[0043] Obtaining Information about Tilt Image Shift Sensitivity

[0044] In the present embodiment, the tilt image shift sensitivity is the amount of image point movement in a direction orthogonal or parallel to a predetermined rotation axis, around which the imaging optical system 101 tilts, and the predetermined rotation axis is orthogonal to the optical axis of the imaging optical system 101 and intersects the optical axis on the imaging plane. Figure 3A The relationship between the image height and the tilt image shift sensitivity in the case of tilting the imaging optical system 101 of the present embodiment is shown, where the image height is in the moving direction of the image point and in the central portion of the image. As Figure 3AAs shown, the higher the image height in the moving direction of the image point, the greater the amount of image point movement when the imaging optical system 101 is tilted. The imaging optical system is designed to optically reduce aberrations by the central projection method. Figure 3B Fig. shows the relationship between the image height and the tilt image shift sensitivity in the case where the imaging optical system 101 of the present embodiment is tilted. The image height is in the direction orthogonal to the moving direction of the image point and in the central portion of the image. As Figure 3B shown, the higher the image height in the direction orthogonal to the moving direction of the image point, the smaller the amount of image point movement when the imaging optical system 101 is tilted. The imaging optical system 101 is designed to be able to reduce barrel aberrations by the central projection method. In the present embodiment, the amount of image point movement for each image height in the case of occurrence of rotational jitter can be obtained by using the tilt image shift sensitivity (which is obtained by using the design values of the imaging optical system 101), and there is no need to use the image height expression based on the projection method or perform arithmetic processing using the amount of distortion. The tilt image shift sensitivity of the present embodiment is a value obtained by dividing the amount of image point movement when the imaging optical system 101 is tilted by 0.5° around a predetermined rotation axis by 0.5°. The tilt angle of the imaging optical system 101 is not limited to 0.5° and can be set appropriately.

[0045] Figure 4 Fig. is a diagram showing a comparison of the image point movement at a predetermined image point position A and the image point movement in the central portion of the image in the case of occurrence of rotational jitter about the Y axis, and schematically shows a state in which the still subject image 301 is distorted into a trapezoidal subject image 302 due to image blur. With a wide-angle lens that optically reduces distortion by the central projection method, when rotational jitter occurs, the trapezoidal distortion such as that occurring in the subject image 302 becomes larger. When each image point on the imaging plane moves along the movement vector of the image point indicated by the arrow, image blur occurs.

[0046] Hereinafter, the amount of image point movement t x0 in the +X-axis direction at the center position O of the imaging plane (the center position O is in the central portion of the image) and the amount of image point movement t y at a predetermined image point position A in the case of occurrence of a rotational jitter amount ω x will be described.

[0047] The amount of image point movement t x0 is represented by the following equation (1), where LS represents the tilt image shift sensitivity at an image height of 0.

[0048] t x0 = ω y ·LS (1)

[0049] The imaging plane on the X-Y plane is a polar coordinate system (R-θ coordinate system), where the origin is the central position O, and the coordinates of the predetermined image point position A are (r, θ). That is, in this embodiment, the predetermined image point position A is a position on the imaging plane represented by multiple parameters. The Figure 3A image height indicated by the horizontal axis of Figure 4 corresponds to the image height h in the R direction in the polar coordinate system of r , and the image height indicated by the horizontal axis of Figure 3B corresponds to the image height h in the direction orthogonal to the R direction (i.e., the θ direction) in the polar coordinate system of Figure 4 . The image height h regarding the tilt image shift sensitivity LS is represented by the following equation (2) θ . The tilt image shift sensitivity coefficient k at r the image height h LS_r (h r ), where LS r (h r ) represents the tilt image shift sensitivity at the image height h r .

[0050] k LS_r (h r ) = LS r (h r ) / LS (2)

[0051] The tilt image shift sensitivity coefficient k at the image height h regarding the tilt image shift sensitivity LS is represented by the following equation (3) θ , where LS LS_θ (h θ ) represents the tilt image shift sensitivity at the image height h θ (h θ ). θ

[0052] k LS_θ (h θ ) = LS θ (h θ ) / LS (3)

[0053] The image point movement amount t x0 is represented by the following equations (4) to (6), where t rx0 represents the parallel component parallel to the straight line OA, and t θX0 represents the orthogonal component orthogonal to the straight line OA.

[0054] t rx0 = t x0 ·cosθ = ω y ·LS·cosθ (4)

[0055] t θx0 = tx0 ·(-sinθ) = -ω y ·LS·sinθ (5)

[0056] |t x0 | = (t rx0 2 +t θx0 2 ) 1 / 2 (6)

[0057] For the sign of the parallel component t rx0 , the direction away from the central position O (i.e., the R direction) is positive, and for the sign of the orthogonal component t θx0 , the direction counterclockwise around the central position O and orthogonal to the R direction (i.e., the θ direction) is positive. The R direction and the θ direction are also referred to as the meridian direction and the sagittal direction, respectively.

[0058] Next, the image point displacement amount t x at a predetermined image point position A will be described. For the tilt image shift sensitivity LS r (h r ), the parallel component t rx parallel to the straight line OA is affected by the tilt image shift sensitivity LS r (r) at an image height of r. The orthogonal component t θx orthogonal to the straight line OA is affected by the tilt image shift sensitivity at an image height of 0. For the tilt image shift sensitivity LS θ (h θ ) in the direction orthogonal to the R direction, the parallel component t rx parallel to the straight line OA is affected by the tilt image shift sensitivity at an image height of 0. The orthogonal component t θx orthogonal to the straight line OA is affected by the tilt image shift sensitivity LS θ (r) at an image height of r. Therefore, the image point displacement amount t x is represented by the following equations (7) to (9), where the parallel component t rx and the orthogonal component t θx are used.

[0059] t rx = k LS_r (r)·k LS_θ (0)·t rx0 = k LS_r (r)·ω y ·LS·cosθ (7)

[0060] t θx = k LS_r (0)·k LS_θ (r)·t θx0 = -kLS_θ (r)·ω y ·LS·sinθ (8)

[0061] |t x |=(t rx 2 +t θx 2 ) 1 / 2 (9)

[0062] As described above, the movement amount t of the image point is calculated x , in the case of a rotational jitter amount ω y about the Y-axis, the movement amount t of the image point x is at the predetermined image point position A. Similarly, in the case of a rotational jitter amount ω x about the X-axis, the movement amount t of the image point at the predetermined image point position A in the polar coordinate system is represented by the following equations (10) to (12) y , where t ry represents the parallel component parallel to the straight line OA, and t θy represents the orthogonal component orthogonal to the straight line OA.

[0063] t ry =k LS_r (r)·k LS_θ (0)·t ry0 =k LS_r (r)·ω x ·LS·sinθ (10)

[0064] t θy =k LS_r (0)·k LS_θ (r)·t θy0 =k LS_θ (r)·ω x ·LS·cosθ (11)

[0065] |t y |=(t ry 2 +t θy 2 ) 1 / 2 (12)

[0066] Therefore, the movement amount t of the image point at the predetermined image point position A in the case of a rotational jitter amount (ω x , ω y ) about a predetermined rotation axis (the predetermined rotation axis is orthogonal to the optical axis and intersects the optical axis on the imaging plane) is represented by the following equations (13) to (15), where t r represents the parallel component parallel to the straight line OA, and t θIndicates the orthogonal component orthogonal to the straight line OA.

[0067] t r = t rx + t ry = k LS_r (r)·LS(ω y ·cosθ + ω x ·sinθ) = K LS1 (r,θ)·ω y + K LS2 (r,θ)·ω x (13)

[0068] t θ = t θx + t θy = k LS_θ (r)·LS(-ω y ·sinθ + ω x ·cosθ) = K LS3 (r,θ)·ω y + K LS4 (r,θ)·ω x (14)

[0069] |t| = (t r 2 + t θ 2 ) 1 / 2 (15)

[0070] The coefficients (K LS1 , K LS2 , K LS3 , K LS4 ) in equations (13) and (14) are as follows.

[0071] K LS1 (r,θ) = k LS_r (r)·LS·cosθ

[0072] K LS2 (r,θ) = k LS_r (r)·LS·sinθ

[0073] K LS3 (r,θ) = -k LS_θ (r)·LS·sinθ

[0074] K LS4 (r,θ) = k LS_θ (r)·LS·cosθ

[0075] As shown in equations (13) to (15), the image point movement amount t includes image stabilization coefficient information (K LS1 , KLS2 , K LS3 , K LS4 ), and the rotational jitter amount (ω x , ω y ), the image stabilization coefficient information (K LS1 , K LS2 , K LS3 , K LS4 ) includes the tilt image shift sensitivity and the position information (r, θ) regarding the image point position. In the present embodiment, the lens memory 106 stores in advance an image stabilization coefficient table as information regarding the tilt image shift sensitivity, and this image stabilization coefficient table includes image stabilization coefficient information (KLS1, KLS2, KLS3, KLS4) in matrix format associated with the image point positions indicated in Figure 5A and Figure 5B . As a result, in the case where a rotational jitter amount (ω x , ω y ) occurs, the image point movement amount t at a predetermined image point position A can be easily obtained. The intervals between the image point positions in the image stabilization coefficient table are set appropriately. The image stabilization coefficient table can be managed not by using a polar coordinate system but by using a rectangular coordinate system.

[0076] In order to reduce the information to be stored in the lens memory 106, the information regarding the tilt image shift sensitivity can be the tilt image shift sensitivity for each image height, or can be information by which the image point movement amount t can be obtained by using the position information regarding a predetermined image point position to be image-stabilized. Further, the position information of the image point position can be information regarding a polar coordinate system, or can be information regarding a predetermined coordinate system such as a rectangular coordinate system. The information regarding the tilt image shift sensitivity can be obtained by using the focal length depending on the specifications of the imaging optical system 101 or the image height expression based on the projection method.

[0077] In the present embodiment, the decentering image shift sensitivity is the image point movement amount in the decentering direction and the direction orthogonal to the decentering direction with respect to the amount of decentering of the image stabilization optical system 1014 with respect to the optical axis of the imaging optical system 101. Figure 6A Indicates the relationship between the image height and the decentering image shift sensitivity in the case of decentering the image stabilization optical system 1014 of the present embodiment, where the image height is in the decentering direction and in the central portion of the image. Figure 6B Indicates the relationship between the image height and the decentering image shift sensitivity in the case of decentering the image stabilization optical system 1014 in the present embodiment, where the image height is in the direction orthogonal to the decentering direction and in the central portion of the image. As Figure 6A and Figure 6BAs shown, the higher the image height, the greater the amount of image point movement when the image stabilization optical system 1014 is decentered. The image stabilization optical system 1014 is designed to reduce decentering distortion. In this embodiment, an appropriate image stabilization driving amount for image blur at a predetermined image point position can be obtained by using the decentering image shift sensitivity, which is obtained by using the design values of the imaging optical system 101. The decentering image shift sensitivity of this embodiment is a value obtained by dividing the amount of image point movement when the image stabilization optical system 1014 is decentered by 0.1 mm by 0.1 mm. However, the decentering amount of the image stabilization optical system 1014 is not limited to 0.1 mm and can be set appropriately.

[0078] Figure 7 It is a diagram showing a comparison between the movement of the image point at a predetermined image point position A and the movement of the image point at the center position of the image when the image stabilization optical system 1014 is decentered. Figure 7 Schematically shows a state in which the still subject image 301 is distorted into a trapezoidal subject image 303 when each image point on the subject image 301 moves along the movement vector of the image point indicated by the arrow.

[0079] Hereinafter, the amount of image point movement s at the center position O of the imaging plane when the image stabilization optical system 1014 is decentered by a decentering amount x in the X-axis direction will be described. x0 and the amount of image point movement s at a predetermined image point position A x .

[0080] The amount of image point movement s x is represented by the following equation (16), where TS represents the decentering image shift sensitivity at an image height of 0.

[0081] s x0 = x·TS (16)

[0082] The imaging plane on the X-Y plane is a polar coordinate system (R-θ coordinate system) with the center position O as the origin, and the coordinates of the predetermined image point position A are (r, θ). The image height indicated by the Figure 6A horizontal axis of Figure 7 corresponds to the image height h r ' in the R direction in the polar coordinate system of Figure 6B , and the image height indicated by the θ horizontal axis of r corresponds to the image height h TS_r ' in the direction orthogonal to the R direction (i.e., the θ direction). The decentering image shift sensitivity coefficient k r (h r ') of the decentering image shift sensitivity TS at the image height hr ') represents the centripetal image shift sensitivity at the image height h r '.

[0083] k TS_r (h r ') = TS r (h r ') / TS (17)

[0084] The centripetal image shift sensitivity coefficient k at the image height h θ ' for the centripetal image shift sensitivity TS is represented by the following equation (18), where TS TS_θ (h θ ') represents the centripetal image shift sensitivity at the image height h θ (h θ ') θ '.

[0085] k TS_θ (h θ ') = TS θ (h θ ') / TS (18)

[0086] The image point displacement amount s x0 is represented by the following equations (19) to (21), where s rx0 represents the parallel component parallel to the straight line OA, and s rx0 represents the orthogonal component orthogonal to the straight line OA

[0087] s rx0 = s x0 · cosθ = x · TS · cosθ (19)

[0088] s θx0 = s x0 · (-sinθ) = -x · TS · sinθ (20)

[0089] |s x0 | = (s rx0 2 + s θx0 2 ) 1 / 2 (21)

[0090] For the sign of the parallel component s rx0 , the direction away from the central position O (i.e., the R direction) is positive, and for the sign of the orthogonal component s θx0 , the direction counterclockwise around the central position O and orthogonal to the R direction (i.e., the θ direction) is positive

[0091] Next, the image point displacement amount s at the predetermined image point position A xFor the centrifugal image shift sensitivity TS in the R direction r (h r )), the parallel component s parallel to the straight line OA rx is affected by the centrifugal image shift sensitivity TS at the image height r r (r). The orthogonal component s orthogonal to the straight line OA θx is affected by the centrifugal image shift sensitivity TS at the image height 0. For the centrifugal image shift sensitivity TS in the direction orthogonal to the R direction θ (h θ ')), the parallel component s parallel to the straight line OA rx is affected by the centrifugal image shift sensitivity TS at the image height 0. The orthogonal component s orthogonal to the straight line OA θx is affected by the centrifugal image shift sensitivity TS at the image height r θ (r). Therefore, the image point movement amount sx is represented by the following equations (22) to (24), where the parallel component s rx and the orthogonal component s θx are used.

[0092] s rx = k TS_r (r)·k TS_θ (0)·s sx0 = k TS_r (r)·x·TS·cosθ (22)

[0093] s θx = k TS_r (0)·k TS_θ (r)·s θx0 = -k TS_θ (r)·x·TS·sinθ (23)

[0094] |s x | = (s rx 2 + s θx 2 ) 1 / 2 (24)

[0095] As described above, the image point movement amount s at the predetermined image point position A is calculated when the image stabilization optical system 1014 is centrifuged by the centrifugation amount x in the X-axis direction x . Similarly, when the image stabilization optical system 1014 is centrifuged by the centrifugation amount y in the Y-axis direction, the image point movement amount s at the predetermined image point position A in the polar coordinate system is represented by the following equations (25) to (27), where s y represents the parallel component parallel to the straight line OA, and s ry represents the orthogonal component orthogonal to the straight line OA θyIndicates the orthogonal component orthogonal to the straight line OA.

[0096] s ry = k TS_r (r)·k TS_θ (0)·s ry0 = k TS_r (r)·y·TS·sinθ (25)

[0097] s θy = k TS_r (0)·k TS_θ (r)·s θy0 = k TS_θ (r)·y·TS·cosθ (26)

[0098] |s y |=(s ry 2 + s θy 2 ) 1 / 2 (27)

[0099] Therefore, when the image stabilization optical system 1014 is eccentric from the optical axis, the amount of image point movement s at the predetermined image point position A is represented by the following equations (28) to (30), where s r represents the parallel component parallel to the straight line OA, and s θ represents the orthogonal component orthogonal to the straight line OA.

[0100] s r = s rx + t ry = k TS_r (r)·TS(x·cosθ + y·sinθ)= K TS1 (r,θ)·x + K TS2 (r,θ)·y (28)

[0101] s θ = s θx + s θy = k TS_θ (r)·TS(-x·sinθ + y·cosθ)= K TS3 (r,θ)·x + K TS4 (r,θ)·y (29)

[0102] |s|=(s r 2 + s θ 2 ) 1 / 2 (30)

[0103] The coefficients (K TS1 , KTS2 , K TS3 , K TS4 ) is as follows.

[0104] K TS1 (r, θ) = k TS_r (r)·TS·cosθ

[0105] K TS2 (r, θ) = k TS_r (r)·TS·sinθ

[0106] K TS3 (r, θ) = -k TS_θ (r)·TS·sinθ

[0107] K TS4 (r, θ) = k TS_θ (r)·TS·cosθ

[0108] As shown in equations (28) to (30), the image point movement amount s includes image stabilization coefficient information (K TS1 , K TS2 , K TS3 , K TS4 ) and the eccentricity amount (x, y). The image stabilization coefficient information (K TS1 , K TS2 , K TS3 , K TS4 ) includes the eccentricity image shift sensitivity and the position information (r, θ) of the image point position. In this embodiment, the lens memory 106 pre-stores an image stabilization coefficient table as information about the eccentricity image shift sensitivity. The image stabilization coefficient table includes image stabilization coefficient information (K TS1 , K TS2 , K TS3 , K TS4 ) in a matrix format associated with the image point position. As a result, the image point movement amount s at a predetermined image point position A when the image stabilization optical system 1014 is eccentric can be easily obtained. The interval between the image point positions in the image stabilization coefficient table is set appropriately. The image stabilization coefficient table can be managed by using a rectangular coordinate system instead of using a polar coordinate system.

[0109] In order to reduce the information to be stored in the lens memory 106, the information about the eccentricity image shift sensitivity can be the eccentricity image shift sensitivity for each image height, or can be information by which the image point movement amount s can be obtained by using the position information of a predetermined image point position to be image-stabilized. In addition, the position information about the image point position can be information about a polar coordinate system, or can be information about a predetermined coordinate system such as a rectangular coordinate system.

[0110] Setting of information on the image stabilization position on the imaging plane

[0111] In this embodiment, the setting mode of the imaging system 1 can be set to the image center image stabilization mode and the image stabilization position setting mode. In the image center image stabilization mode, the position of a predetermined image point (image stabilization position) to be image-stabilized is set to the center of the imaging plane. In the image stabilization position setting mode, the image stabilization position is set to a predetermined image point position other than the center of the imaging plane. When the image stabilization position setting mode is set, the image stabilization position can be set via the display operation unit 203. The position that can be set via the display operation unit 203 can be associated with the image point position for performing autofocus or automatic photometry. The image point position for performing autofocus can be a position automatically detected by pupil detection, person detection, etc. Information on the image stabilization position (r, θ) on the imaging plane is sent to the camera microcomputer 202, and the image stabilization coefficient information to be used is selected from the image stabilization coefficient table.

[0112] Motion detection signal

[0113] The gyro sensor 205 detects the angular velocity about a plurality of rotation axes of the imaging system 1 and outputs information on the amount of rotational jitter as a motion detection signal. In this embodiment, the gyro sensor 205 detects the angular velocity about the X-axis and the Y-axis and outputs information on the amount of rotational jitter (ω x , ω y ). The acceleration sensor 206 detects the acceleration in the directions of a plurality of axes of the imaging system 1 and outputs information on the amount of translational jitter as a motion detection signal. In this embodiment, the acceleration sensor 206 detects the acceleration in the X-axis direction and the Y-axis direction and outputs information on the amount of translational jitter (a x , a y ). The gyro sensor 205 may include a plurality of sensors, each of which detects the angular velocity about one axis. Similarly, the acceleration sensor 206 may include a plurality of sensors, each of which detects the acceleration in one direction.

[0114] Obtaining the image stabilization driving amount

[0115] The camera microcomputer 202 obtains an image stabilization drive amount by using information on tilt image shift sensitivity, information on centrifugal image shift sensitivity, information on the image stabilization position, and a motion detection signal. For example, when reducing image blurring at a predetermined image point position A by OIS, the image stabilization optical system 1014 can be moved so that the image point movement amount t caused by rotational jitter and the image point movement amount s caused by centrifuging the image stabilization optical system 1014 cancel each other out. Specifically, the image point movement amount t obtained by decomposing the image point movement amount t caused by rotational jitter into two orthogonal components in the polar coordinate system (t r , t θ ) and the image point movement amount s obtained by decomposing the image point movement amount s caused by centrifuging the image stabilization optical system 1014 into two orthogonal components in the polar coordinate system (s r , s θ ) can cancel each other out, that is, s r = -t r and s θ = -t θ . That is, the following equations (31) and (32) can be satisfied.

[0116] K TS1 (r,θ)·x + K TS2 (r,θ)·y = -K LS1 (r,θ)·ω y - K LS2 (r,θ)·ω x (31)

[0117] K TS3 (r,θ)·x + K TS4 (r,θ)·y = -K LS3 (r,θ)·ω y - K LS4 (r,θ)·ω x (32)

[0118] The camera microcomputer 202 can obtain the image stabilization drive amount (x, y) of the image stabilization optical system 1014 from the image point movement amounts (t, s) by using equations (31) and (32).

[0119] Figure 8 is a diagram showing arrows according to the present embodiment, and each arrow indicates the ratio and direction of the image point movement amount of the remaining blur residue at each image point after reducing the image blurring at the predetermined image point position A by OIS. As Figure 8As shown, the image blur at the predetermined image point position A is well reduced, while the image blur in the central part of the image is retained. Image point movement with the same motion vector as that at the image point position A occurs at the image point position A' that is symmetric to the origin of the predetermined image point position A (where the central part of the image is taken as the origin), thereby reducing the image blur at the image point position A' as well. Therefore, by appropriately setting the image stabilization position at a predetermined position that is not on the optical axis within the range where the image blur in the central part of the image is not obvious, the image blur can be reduced while the difference in the amount of image blur in the entire image is minimized.

[0120] Since equations (31) and (32) are linear simultaneous equations related to the image stabilization driving amounts (x, y) of the image stabilization optical system 1014, the image stabilization driving amounts (x, y) of the image stabilization optical system 1014 can be represented by the following equations (33) and (34).

[0121] x = K 1 (r,θ)ω x +K 2 (r,θ)ω y (33)

[0122] y = K 3 (r,θ)ω x +K 4 (r,θ)ω y (34)

[0123] The coefficients (K 1 , K 2 , K 3 , K 4 ) in equations (33) and (34) are as follows.

[0124] K 1 (r,θ) = (-K LS2 (r,θ)·K TS4 (r,θ)+K LS4 (r,θ)·K TS2 (r,θ)) / (K TS1 (r,θ)·K TS4 (r,θ)-K TS2 (r,θ)·K TS3 (r,θ))

[0125] K 2 (r,θ) = (-K LS1 (r,θ)·K TS4 (r,θ)+K LS3 (r,θ)·K TS2 (r,θ)) / (K TS1 (r,θ)·KTS4 (r,θ)-K TS2 (r,θ)·K TS3 (r,θ))

[0126] K 3 (r,θ)=(-K LS2 (r,θ)·K TS3 (r,θ)+K LS4 (r,θ)·K TS1 (r,θ)) / (K TS2 (r,θ)·K TS3 (r,θ)-K TS1 (r,θ)·K TS4 (r,θ))

[0127] K 4 (r,θ)=(-K LS1 (r,θ)·K TS3 (r,θ)+K LS3 (r,θ)·K TS1 (r,θ)) / (K TS2 (r,θ)·K TS3 (r,θ)-K TS1 (r,θ)·K TS4 (r,θ))

[0128] As shown in equations (33) and (34), the image stabilization driving amounts (x, y) include image stabilization coefficient information (K 1 , K 2 , K 3 , K 4 ) and rotational jitter amounts (ω x , ω y ). The lens memory 106 can store an image stabilization coefficient table including image stabilization coefficient information (K 1 , K 2 , K 3 , K 4 ) in a matrix format. In this case, it is possible to more easily obtain the image stabilization driving amounts (x, y) of a predetermined image point position A in the case where rotational jitter amounts (ω x , ω y ) occur.

[0129] For image blur caused by translational jitter, the image stabilization driving amount can be obtained by using the information on the translational jitter amount output from the acceleration sensor 206. The translational jitter amounts (a x , a y ) can be converted into rotational jitter amounts (ω x , ω y) to obtain the image stabilization driving amount for translational jitter. In the case where rotational jitter and translational jitter occur simultaneously, the image stabilization driving amount can be obtained by adding the image stabilization driving amount for translational jitter and the image stabilization driving amount for rotational jitter. The image stabilization driving amount for translational jitter at a predetermined image point position can be obtained by multiplying the converted rotational jitter amount by the image stabilization coefficient included in the information regarding the tilt image shift sensitivity.

[0130] The tilt image shift sensitivity and the centrifugal image shift sensitivity vary according to the distance (focus position) to the object focused by the imaging optical system 101 and the focal length (imaging angle of view). In the present embodiment, the lens memory 106 stores a plurality of different image stabilization coefficient tables for the focus position determined by the focusing optical system 1011 and the focal length determined by the zoom optical system 1012. As a result, even during zooming and focusing, image blur at a predetermined image point position can be reduced well.

[0131] The lens device 100 can be detachably attached to the imaging device 200. In this case, the information regarding the tilt image shift sensitivity and the information regarding the centrifugal image shift sensitivity suitable for each lens device 100 can be used. As a result, even when different lens devices 100 are attached to and used with the imaging device 200, image blur at a predetermined image point position can be reduced well.

[0132] Second Embodiment

[0133] In the present embodiment, a method for reducing image blur by both OIS and IIS will be described. In the present embodiment, only the differences from the first embodiment will be described. In the present embodiment, the schematic configuration of the imaging system 1 and the method for obtaining the image stabilization driving amount of the image stabilization optical system 1014 are the same as those according to the first embodiment, and thus the description thereof will be omitted.

[0134] Figure 9It is a structural diagram showing the lens microcomputer 102 and the camera microcomputer 202 of this embodiment. The lens microcomputer 102 includes a lens acquisition unit 1021 and an OIS control unit 1022. The camera microcomputer 202 includes a camera acquisition unit 2021, an OIS image stabilization coefficient information acquisition unit (first acquisition unit) 2022, an IIS image stabilization coefficient information acquisition unit (third acquisition unit) 2023, and a setting unit 2024. The camera microcomputer 202 further includes an OIS image stabilization drive amount acquisition unit (second acquisition unit) 2025, an IIS image stabilization drive amount acquisition unit (fourth acquisition unit) 2026, and an IIS control unit 207. In this embodiment, the camera microcomputer 202 includes an OIS image stabilization coefficient information acquisition unit 2022, an IIS image stabilization coefficient information acquisition unit 2023, an OIS image stabilization drive amount acquisition unit 2025, and an IIS image stabilization drive amount acquisition unit 2026, but the present invention is not limited thereto, and the lens microcomputer 102 may include these. Alternatively, the lens microcomputer 102 may include an OIS image stabilization coefficient information acquisition unit 2022 and an OIS image stabilization drive amount acquisition unit 2025, and the camera microcomputer 202 may include an IIS image stabilization coefficient information acquisition unit 2023 and an IIS image stabilization drive amount acquisition unit 2026. Alternatively, the camera microcomputer 202 may include an OIS image stabilization coefficient information acquisition unit 2022 and an OIS image stabilization drive amount acquisition unit 2025, and the lens microcomputer 102 may include an IIS image stabilization coefficient information acquisition unit 2023 and an IIS image stabilization drive amount acquisition unit 2026.

[0135] In this embodiment, since image blur at a predetermined image point position A is reduced by OIS and IIS, a higher image stabilization effect can be achieved compared to the case where image blur is reduced only by OIS. When reducing image blur at a predetermined image point position A by IIS, the image sensor 201 can be moved so as to eliminate the image point movement amount t represented by the equations (13) to (15) described in the first embodiment. The image stabilization drive amount x' in the X-axis direction and the image stabilization drive amount y' in the Y-axis direction of the IIS actuator 210 are represented by the following equations (35) and (36).

[0136] x′ = t r ·cosθ - t θ ·sinθ

[0137] = ω y {k LS_θ (r)·sin 2 θ + k LS_r (r)·cos 2 θ}LS + ω x {kLS_r (R)-K LS_θ (R)}LS·sinθ·cosθ

[0138] =K' 1 (r,θ)·ω y +K' 2 (r,θ)·ω x (35)

[0139] y' = t r ·sinθ + t θ ·cosθ

[0140] =ω y {K LS_r (r)-K LS_θ (r)}LS·sinθ·cosθ + ω x {K LS_r (r)·sin 2 θ + K LS_θ (r)·cos 2 θ}LS

[0141] =K' 3 (r,θ)·ω y +K' 4 (r,θ)·ω x (36)

[0142] The coefficients (K 1 , K 2 , K 3 , K 4 ) in equations (35) and (36) are as follows.

[0143] K' 1 (r,θ) = {K LS_θ (r)·sin 2 θ + K LS_r (r)·cos 2 θ}LS

[0144] K' 2 (r,θ) = {K LS_r (r)-K LS_θ (r)}LS·sinθ·cosθ

[0145] K' 3 (r,θ) = {K LS_r (r)-K LS_θ (r)}LS·sinθ·cosθ

[0146] K' 4 (r,θ) = {K LS_r (r)·sin 2θ + k LS_θ (r)·cos 2 θ}LS

[0147] As shown in equations (35) and (36), the image stabilization driving amounts (x', y') include image stabilization coefficient information (K' 1 , K' 2 , K' 3 , K' 4 ) and rotational jitter amounts (ω x , ω y ). The lens memory 106 can store an image stabilization coefficient table including the image stabilization coefficient information (K' 1 , K' 2 , K' 3 , K' 4 ) in a matrix format as information about the tilt image shift sensitivity. Using K'1 etc. instead of the above image stabilization coefficient information (K 1 , K 2 , K 3 , K 4 ) enables easier acquisition of the image stabilization driving amounts (x', y') of a predetermined image point position A in the case where rotational jitter amounts (ω x , ω y ) occur.

[0148] Figure 10A Shows the process from the state of turning on the power of the imaging system 1 to the state where the image stabilization function is turned on and the imaging device 200 becomes the imaging standby state. Figure 10B Shows the process for image stabilization of rotational jitter during imaging.

[0149] The process is started by turning on the power of the imaging system 1 Figure 10A .

[0150] In step S11, the lens microcomputer 102 sends the optical design information of the imaging optical system 101, which has been stored in the lens memory 106 and acquired by the lens acquisition unit 1021, to the camera microcomputer 202.

[0151] In step S12, the camera acquisition unit 2021 acquires the optical design information sent by the lens microcomputer 102.

[0152] In step S13, the camera acquisition unit 2021 acquires the information about the image stabilization position set in the imaging device 200.

[0153] In step S14, the camera microcomputer 202 determines whether the OIS function is turned on. If the camera microcomputer 202 determines that the OIS function is turned on, the process proceeds to step S15. If the camera microcomputer 202 determines that the OIS function is not turned on, the process proceeds to step S16.

[0154] In step S15, the OIS image stabilization coefficient information acquisition unit 2022 obtains OIS image stabilization coefficient information (K 1 , K 2 , K 3 , K 4 ) from the image stabilization coefficient table based on the information about the image stabilization position and the information about the focal length and the object distance set in the lens device 100.

[0155] In step S16, the camera microcomputer 202 determines whether the IIS function is turned on. If the camera microcomputer 202 determines that the IIS function is turned on, the process proceeds to step S17. If the camera microcomputer 202 determines that the IIS function has not been turned on, the camera microcomputer 202 sets the imaging device 200 to the imaging standby state.

[0156] In step S17, the IIS image stabilization coefficient information acquisition unit 2023 obtains IIS image stabilization coefficient information (K' 1 , K' 2 , K' 3 , K' 4 ) from the image stabilization coefficient table based on the information about the image stabilization position and the information about the focal length and the object distance set in the lens device 100.

[0157] In the process described below Figure 10B , it is assumed that both the OIS function and the IIS function are turned on.

[0158] In response to camera shake detected by the gyro sensor 205 during imaging (exposure) (in response to the detection of the angular velocity), the camera microcomputer 202 obtains information about the rotational shake amount from the gyro sensor 205 in step S21.

[0159] In step S22, the setting unit 2024 sets the ratio (share ratio) between the image stabilization by OIS and the image stabilization by IIS. In this embodiment, the share ratio is set such that 50% of the image stabilization is performed by OIS and 50% of the image stabilization is performed by IIS.

[0160] In step S23, the OIS image stabilization drive amount acquisition unit 2025 uses the OIS image stabilization coefficient information (K 1 , K 2 , K 3, K 4 ) and information on the rotational jitter amount and the share ratio to obtain the OIS image stabilization driving amount (first image stabilization driving amount).

[0161] In step S24, the OIS control unit 1022 acquires the position of the image stabilization optical system 1014 output from the OIS encoder 103.

[0162] In step S25, the OIS control unit 1022 acquires the OIS driving amount of the OIS actuator 105 so as not to exceed the movable range of the OIS actuator 105. If the OIS driving amount and the OIS image stabilization driving amount match, the amount of image blur is reduced by 50% by the OIS.

[0163] After the process of step S25, the OIS control unit 1022 drives the OIS actuator 105 via the OIS driver 104.

[0164] In step S26, the IIS image stabilization driving amount acquisition unit 2026 obtains the IIS image stabilization driving amount (second image stabilization driving amount) by using the IIS image stabilization coefficient information (K' 1 , K' 2 , K' 3 , K' 4 ), information on the rotational jitter amount, and the share ratio.

[0165] In step S27, the IIS control unit 207 acquires the position of the image sensor 201 output from the IIS encoder 208.

[0166] In step S28, the IIS control unit 207 acquires the IIS driving amount of the IIS actuator 210 so as not to exceed the movable range of the IIS actuator 210. If the IIS driving amount and the IIS image stabilization driving amount match, the amount of image blur is reduced by 50% by the IIS.

[0167] The processes of steps S26 to S28 are executed in parallel with the processes of steps S23 to S25.

[0168] Example

[0169] Hereinafter, examples of the imaging optical system 101 of the present disclosure will be described with reference to the drawings.

[0170] Figure 11 And Figure 13 are cross-sectional views of the optical system L0 focused on an object at infinity at the wide-angle end according to the first example and the second example, respectively. The arrows in each cross-sectional view indicate the movement trajectories of the respective lens units during zooming from the wide-angle end to the telephoto end. Figure 15It is a cross-sectional view showing an optical system L0 focused on an object at infinity according to the third embodiment. Figure 15 The arrows in [ ] indicate the movement trajectories of the lens units during focusing from infinity to close range. The optical system L0 according to each example is used in imaging devices such as digital video cameras, digital still cameras, broadcast cameras, surveillance cameras, and smartphone cameras.

[0171] In each cross-sectional view, the left side is the object side, and the right side is the image side. The optical system L0 according to each example includes a plurality of lens units. In this specification, a lens unit is a set of lenses that moves and stops as a whole during zooming, focusing, or image stabilization. That is, in the optical system L0 according to each example, each distance between adjacent lens units changes during zooming or focusing. A lens unit may be a single lens or may include a plurality of lenses. A lens unit may include an aperture.

[0172] SP represents the aperture. IP represents the image plane and is the imaging plane of an image sensor (photoelectric conversion element) such as a CCD sensor and a CMOS sensor. During OIS, the image stabilization optical system is eccentric from the optical axis of the optical system L0.

[0173] Figure 12 and Figure 14 are aberration diagrams when the optical system L0 at the wide-angle end according to the first embodiment and the second embodiment is focused on an object at infinity, respectively. Figure 16 is an aberration diagram when the optical system L0 according to the third embodiment is focused on an object at infinity.

[0174] In each spherical aberration diagram, Fno represents the F-number and indicates the amount of spherical aberration of the d-line (wavelength 587.6 nm) and the g-line (wavelength 435.8 nm). In each astigmatism diagram, S indicates the amount of astigmatism of the sagittal image plane, and M indicates the amount of astigmatism of the meridional image plane. In each distortion diagram, it indicates the amount of distortion of the d-line. Each chromatic aberration diagram indicates the amount of lateral chromatic aberration of the g-line. ω represents the imaging half-angle of view (°).

[0175] Numerical examples 1 to 3 corresponding to Examples 1 to 3 are given below.

[0176] In the surface data of each numerical example, r represents the radius of curvature of the optical surface, and d (mm) represents the on-axis distance (distance on the optical axis) between the m-th surface and the (m + 1)-th surface, and m represents the surface number counted from the light incident surface. nd represents the refractive index of the d-line of the optical member, and νd represents the Abbe number of the optical member. The Abbe number νd of a certain material is represented by the following equation, where Nd, NF, and NC represent the refractive indices of the d-line (wavelength 587.6 nm), F-line (wavelength 486.1 nm), and C-line (wavelength 656.3 nm) in the Fraunhofer lines, respectively.

[0177] νd = (Nd - 1) / (NF - NC)

[0178] In each numerical example, d, focal length (mm), F-number, and half field of view (°) are values in a state where the optical system L0 according to the example is focused on an object at infinity. The back focal length (BF) is the air conversion length of the distance from the last lens surface (the lens surface closest to the image side) on the optical axis to the paraxial image plane. The total optical length is the length obtained by adding the back focal length and the distance from the front lens surface (the lens surface closest to the object side) to the last lens surface on the optical axis.

[0179] * A symbol is attached to the right of the surface number of the optical surface that is an aspherical surface. The aspherical shape is represented by the following equation, where X represents the displacement amount from the surface vertex in the optical axis direction, h represents the height from the optical axis in the direction orthogonal to the optical axis, R represents the paraxial curvature radius, k represents the conic constant, and A4, A6, A8, A10, A12 represent the aspherical coefficients of each order.

[0180] X = (h 2 / R) / [1 + {1 - (1 + k)(h / R) 2} 1 / 2 + A4 × h 4 + A6 × h 6 + A8 × h 8 + A10 × h 10 + A12 × h 12 + A14 × h 14 + A16 × h 16

[0181] In the “e±XX” in each aspherical coefficient, it means “×10± XX ”.

[0182] In each numerical example, tilt image shift sensitivity data and centrifugal image shift sensitivity data are given. The method for obtaining these data is described below with reference to Figures 17A to 17C the description.

[0183] Figures 17A to 17C is the ray trace diagram of the chief rays of the d-line for each field of view (the chief ray with a half field of view of 0 and the chief ray with a half field of view of ω), and this chief ray is incident from the object side surface of the optical system L0 according to Example 1. Figures 17A to 17C shows the optical system L0 in a stationary state, a state where the image stabilization optical system tilts by an angle ω around the X-axis with the intersection of the image plane IP and the optical axis as the center x and a state where the image stabilization optical system is centrifuged by a centrifugal amount y in the Y-axis direction.

[0184] By the amount of image point movement Δy LSr (hr ) Divide by the tilt angle ω x to obtain the tilt image shift sensitivity of each image height in the tilt direction (R direction), and the image point movement amount Δy LSr (h r ) is the difference in the imaging positions on the image plane IP corresponding to the respective half viewing angles of Figure 17A and Figure 17B . By using the image point movement amount Δy of each image height h in the X-axis direction θ , to obtain the tilt image shift sensitivity of each image height in the direction orthogonal to the tilt direction. In each example, the tilt image shift sensitivity is obtained based on the image point movement amount when the optical system L0 is tilted by 0.5°. For the sign of the tilt angle ω LSθ , x the counterclockwise direction in Figure 17B is positive, while Figure 17B the clockwise direction in Figure 17B is negative. For the sign of the image point movement amount Δy, Figure 17B the upward direction in

[0185] is positive, while TSr (h r ) Divide the image point movement amount Δy by the decentration amount y of the image stabilization optical system to obtain the decentration image shift sensitivity of each image height in the decentration direction (R direction), and the image point movement amount Δy TSr is the difference in the imaging positions on the image plane IP corresponding to the respective half viewing angles of Figure 17A and Figure 17C . In each example, by using the image point movement amount Δy of each image height h in the X-axis direction θ , to obtain the decentration image shift sensitivity of each image height in the direction orthogonal to the decentration direction. The decentration image shift sensitivity data in each embodiment is obtained based on the image point movement amount when the image stabilization optical system is decentered by 0.1 mm. TSθ

[0186] [Numerical Example 1]

[0187] Unit: mm

[0188] Surface data

[0189]

[0190]

[0191]

[0192] Aspherical data

[0193] The 12th surface ​

[0194] K = 0.00000e+000 A4 = -5.69442e-006 A6 = -2.29053e-009

[0195] A8 = -4.72363e-011 A10 = 4.65343e-013 A12 = -1.99227e-015

[0196] The 22nd surface

[0197] K = 0.00000e+000 A4 = 1.87606e-006 A6 = 1.45872e-009

[0198] A8 = 2.78338e-011 A10 = -2.10980e-013 A12 = 3.98590e-016

[0199] The 30th surface

[0200] K = 0.00000e+000 A4 = -2.01869e-005 A6 = 6.17344e-008

[0201] A8 = -2.64177e-010 A10 = -2.98832e-013 A12 = 2.64092e-015

[0202] The 31st surface

[0203] K = 0.00000e+000 A4 = 1.63774e-006 A6 = 9.32838e-008

[0204] A8 = -2.34772e-010 A10 = -7.39973e-013 A12 = 4.51086e-015

[0205] The 34th surface

[0206] K = 0.00000e+000 A4 = -2.51719e-005 A6 = 1.25180e-007

[0207] A8 = -5.32709e-010 A10 = 5.08044e-013 A12 = 7.30860e-016

[0208] The 35th surface

[0209] K = 0.00000e+000 A4 = -2.60571e-005 A6 = 1.26402e-007

[0210] A8 = -6.23562e-010 A10 = 1.45147e-012 A12 = -1.39940e-015

[0211] Various data

[0212]

[0213]

[0214]

[0215] At the wide-angle end, the tilt image shift sensitivity data of each image height in the tilt direction

[0216]

[0217] At the wide-angle end, the tilt image shift sensitivity data of each image height in the direction orthogonal to the tilt direction

[0218]

[0219] At the wide-angle end, the decentering image shift sensitivity data of each image height in the decentering direction

[0220]

[0221] At the wide-angle end, the decentering image shift sensitivity data of each image height in the direction orthogonal to the decentering direction

[0222]

[0223] [Numerical example 2]

[0224] Unit: mm

[0225] Surface data

[0226]

[0227]

[0228] Aspherical data

[0229] The first surface

[0230] K = 0.00000e+000 A4 = 8.30213e-006 A6 = -1.33976e-008

[0231] A8 = 4.25008e-011 A10 = -8.60253e-014 A12 = 1.03363e-016

[0232] A14 = -7.03702e-020 A16 = 2.16318e-023

[0233] Second surface

[0234] K = -9.81344e-001 A4 = 4.49709e-007 A6 = -2.34544e-008

[0235] A8 = -1.05516e-010 A10 = 8.07443e-013 A12 = -2.78552e-015

[0236] A14 = 3.05128e-018

[0237] Third surface

[0238] K = 0.00000e+000 A4 = -9.01759e-006 A6 = -1.39642e-007

[0239] A8 = 1.23272e-009 A10 = -3.49283e-012 A12 = 3.62808e-015

[0240] A14 = 5.24953e-019 A16 = -2.43479e-021

[0241] Fourth surface

[0242] K = 0.00000e+000 A4 = 6.34981e-006 A6 = -1.29871e-007

[0243] A8 = 1.67920e-009 A10 = -6.48374e-012 A12 = 1.50043e-014

[0244] A14 = -1.59777e-017

[0245] Twenty-seventh surface

[0246] K = 0.00000e+000 A4 = -8.04129e-005 A6 = 2.64851e-007

[0247] A8 = -1.06038e-009 A10 = 4.87911e-012 A12 = -8.56493e-015

[0248] A14 = -1.17880e-018 A16 = -3.10043e-023

[0249] Twenty-eighth surface

[0250] K = 0.00000e+000 A4 = -6.00659e-005 A6 = 2.67376e-007

[0251] A8 = -7.05021e-010 A10 = 2.04492e-012 A12 = -2.97985e-015

[0252] Various data

[0253]

[0254]

[0255] At the wide-angle end, the tilt image shift sensitivity data of each image height in the tilt direction

[0256]

[0257] At the wide-angle end, the tilt image shift sensitivity data of each image height in the direction orthogonal to the tilt direction

[0258]

[0259]

[0260] At the wide-angle end, the decentering image shift sensitivity data of each image height in the decentering direction

[0261]

[0262] At the wide-angle end, the decentering image shift sensitivity data of each image height in the direction orthogonal to the decentering direction

[0263]

[0264]

[0265] [Numerical example 3]

[0266] Unit: mm

[0267] Surface data

[0268]

[0269]

[0270] Aspherical data

[0271] The 15th surface

[0272] K = 0.00000e+000 A4 = 2.14904e-005 A6 = -6.26885e-009 A8 = 3.11936e-010 A10 = -1.96590e-012 A12 = 3.25155e-015

[0273] Various data

[0274]

[0275] Wide angle Telephoto

[0276] d17 1.50 11.92

[0277] When an object at infinity is focused, the tilt image shift sensitivity data of each image height in the tilt direction

[0278]

[0279] When an object at infinity is focused, the tilt image shift sensitivity data of each image height in the direction orthogonal to the tilt direction

[0280]

[0281] When an object at infinity is focused, the decentering image shift sensitivity data of each image height in the decentering direction

[0282]

[0283] When an object at infinity is focused, the decentering image shift sensitivity data of each image height in the direction orthogonal to the decentering direction

[0284]

[0285]

[0286] As described above, by using the configuration of the present disclosure, it is possible to easily and favorably reduce image blurring at a predetermined image point position including the optical axis center.

[0287] In each embodiment, the information on the decentering image shift sensitivity of the image stabilization optical system 1014 associated with the image point position is an image stabilization coefficient table including the image stabilization coefficient information associated with the image point position in a matrix format, but the present disclosure is not limited thereto. The information on the decentering image shift sensitivity of the image stabilization optical system 1014 associated with the image point position may be the decentering image shift sensitivity TS r (h r ) and TS θ (h θ), or can be the off-axis image stabilization coefficient information (K obtained based on the centripetal image shift sensitivity TS1 , K TS2 , K TS3 , K TS4 ). Alternatively, the information on the centripetal image shift sensitivity of the image stabilization optical system 1014 associated with the image point position can be the image stabilization coefficient information (K calculated by combining the information on the tilt image shift sensitivity of the imaging optical system 101 associated with the image point position 1 , K 2 , K 3 , K 4 ). That is, the information on the centripetal image shift sensitivity of the image stabilization optical system 1014 associated with the image point position can be any information that enables obtaining the movement amount of a predetermined image point position with respect to the centripetal of the image stabilization optical system 1014.

[0288] In various embodiments, the information on the tilt image shift sensitivity of the imaging optical system 101 associated with the image point position is an image stabilization coefficient table including the image stabilization coefficient information associated with the image point position in matrix format, but the present disclosure is not limited thereto. The information on the tilt image shift sensitivity of the imaging optical system 101 associated with the image point position can be an image height expression based on the focal length or projection method specified in the imaging optical system 101, or can be the tilt image shift sensitivity LS r (h r ) and LS θ (h θ ). Alternatively, the information on the tilt image shift sensitivity of the imaging optical system 101 associated with the image point position can be the off-axis image stabilization coefficient information (K obtained based on the tilt image shift sensitivity LS1 , K LS2 , K LS3 , K LS4 ). That is, the information on the tilt image shift sensitivity of the imaging optical system 101 associated with the image point position can be any information that enables obtaining the movement amount of a predetermined image point position with respect to the tilt of the imaging optical system 101.

[0289] In each embodiment, the centrifugal image shift sensitivity and the tilt image shift sensitivity are described as information on each image height in the centrifugal direction (R direction) or in a direction orthogonal to the centrifugal direction of the image stabilization optical system 1014. However, the centrifugal image shift sensitivity and the tilt image shift sensitivity may be information determined for each image point position on the entire imaging plane in a predetermined direction on the imaging plane. In this case, the centrifugal image shift sensitivity or the tilt image shift sensitivity can be directly obtained based on the amount of image point movement on the entire imaging plane obtained by using the design values of the imaging optical system 101.

[0290] In each numerical example, the image point position is obtained by using the imaging position of the chief ray, but the image point position can be obtained by using the peak position of the modulation transfer function (MTF).

[0291] The camera microcomputer 202 can perform image stabilization by using an electronic image stabilization function that changes the effective pixel region of the image sensor 201. That is, the camera microcomputer 202 can be used as one of the image stabilization units.

[0292] The projection method of the imaging optical system 101 is not limited to the central projection method, and can also be other projection methods such as the equidistant projection method.

[0293] Other embodiments

[0294] Embodiments of the present invention can also be implemented by a computer of a system or apparatus that reads and executes computer-executable instructions (for example, one or more programs) recorded on a storage medium (which may also be more completely referred to as a "non-transitory computer-readable storage medium") to perform one or more functions of the above-described embodiments, and / or includes one or more circuits (for example, an application specific integrated circuit (ASIC)) for performing one or more functions of the above-described embodiments. Moreover, embodiments of the present invention can be implemented by a method of causing the computer of the system or apparatus to, for example, read and execute the computer-executable instructions from the storage medium to perform one or more functions of the above-described embodiments, and / or control the one or more circuits to perform one or more functions of the above-described embodiments. The computer may include one or more processors (for example, a central processing unit (CPU), a microprocessing unit (MPU)), and may include a network of separate computers or separate processors to read and execute the computer-executable instructions. The computer-executable instructions may be provided to the computer from a network or the storage medium, for example. The storage medium may include, for example, a hard disk, a random access memory (RAM), a read only memory (ROM), a memory of a distributed computing system, an optical disc (such as a compact disc (CD), a digital versatile disc (DVD), or a Blu-ray disc (BD)TM ) one or more of a flash memory device, a memory card, and the like.

[0295] Embodiments of the present invention can also be implemented by the following method, that is, software (program) that executes the functions of the above embodiments is provided to a system or device through a network or various storage media, and a method in which a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0296] Although the present invention has been described with reference to exemplary embodiments, it should be understood that the present invention is not limited to the disclosed exemplary embodiments. The scope of the appended claims should be given the broadest interpretation so as to cover all such variations and equivalent structures and functions.

Claims

1. A control device, which comprises: A first acquisition unit configured to acquire information on image shift sensitivity from a storage unit storing an image stabilization coefficient table as information on image shift sensitivity of each image point position with respect to the eccentricity of an image stabilization optical system provided in an imaging optical system, the image stabilization coefficient table including image stabilization coefficient information in a matrix format associated with the image point position, the image stabilization coefficient information including eccentricity image shift sensitivity and position information of the image point position; and A second acquisition unit configured to acquire a first image stabilization driving amount during image stabilization of the image stabilization optical system, characterized in that the second acquisition unit acquires the first image stabilization driving amount associated with the predetermined image point position by using the information on the image shift sensitivity associated with the predetermined image point position.

2. The control device according to claim 1, wherein information on image shift sensitivity is acquired by using design values of the imaging optical system.

3. The control device according to claim 1, wherein the information on image shift sensitivity is information that can be used to acquire the amount of movement of the predetermined image point position with respect to the eccentricity of the image stabilization optical system.

4. The control device according to claim 1, wherein the information on image shift sensitivity is information determined for each position on the image plane.

5. The control device according to claim 1, wherein information on image shift sensitivity is acquired by using information that can be used to acquire the amount of movement of the predetermined image point position with respect to the tilt of the imaging optical system.

6. The control device according to claim 1, wherein the first image stabilization driving amount is acquired by using information on shake and information on image shift sensitivity.

7. The control device according to claim 1, wherein the first image stabilization driving amount is acquired by using information on shake, information on the predetermined image point position, and information on image shift sensitivity.

8. The control device according to claim 6, wherein the information on shake includes information on angular velocities about a plurality of rotation axes.

9. The control device according to claim 6, wherein the information on shake includes information on accelerations in a plurality of axial directions.

10. The control device according to claim 1, wherein the predetermined image point position is a position on the image plane and is represented by a plurality of parameters.

11. The control device according to any one of claims 1 to 10, wherein the information on image shift sensitivity varies according to the focal length of the imaging optical system.

12. The control device according to claim 1, wherein the information on image shift sensitivity varies according to the distance to an object to be focused.

13. The control device according to claim 1, the control device further comprises: A third acquisition unit configured to acquire information that can be used to acquire the amount of movement of the predetermined image point position with respect to the tilt of the imaging optical system; and A fourth acquisition unit configured to acquire a second image stabilization driving amount of an image stabilization unit during image stabilization, the image stabilization unit being configured to perform image stabilization. Wherein, the fourth acquisition unit acquires the second image stabilization driving amount associated with the predetermined image point position by using information capable of acquiring a movement amount of the predetermined image point position for obtaining the tilt of the imaging optical system.

14. The control device according to claim 13, Wherein, The image stabilization unit eccentrically positions the image sensor from the optical axis of the imaging optical system.

15. The control device according to claim 13, Wherein, The image stabilization unit changes the effective pixel region of the image sensor.

16. The control device according to any one of claims 13 to 15, the control device further Comprises: A setting unit configured to set a ratio between image stabilization performed by the image stabilization optical system and image stabilization performed by the image stabilization unit, and Wherein, the first image stabilization driving amount and the second image stabilization driving amount are set based on the ratio.

17. An imaging device, which Comprises: An image sensor; And The control device according to any one of claims 1 to 16.

18. The imaging device according to claim 17, the imaging device further Comprises: A memory unit configured to store information related to image shift sensitivity regarding eccentricity of the image stabilization optical system, the information being associated with the image point position of the imaging optical system.

19. A lens device, which Comprises: An imaging optical system; And The control device according to any one of claims 1 to 16.

20. The lens device according to claim 19, the lens device further Comprises: A memory unit configured to store information related to image shift sensitivity regarding eccentricity of the image stabilization optical system, the information being associated with the image point position of the imaging optical system.

21. A camera system, which Comprises: A first acquisition unit configured to acquire information on image shift sensitivity from a storage unit storing an image stabilization coefficient table as information on image shift sensitivity for each image point position with respect to eccentricity of an image stabilization optical system provided in an imaging optical system, the image stabilization coefficient table including image stabilization coefficient information in a matrix format associated with the image point position, the image stabilization coefficient information including position information of the eccentricity image shift sensitivity and the image point position; And A second acquisition unit configured to acquire a first image stabilization driving amount of the image stabilization optical system during image stabilization, Characterized in that the second acquisition unit comprises: A lens device configured to acquire the first image stabilization driving amount associated with the predetermined image point position by using information on the image shift sensitivity associated with the predetermined image point position; A third acquisition unit configured to acquire information capable of acquiring a movement amount of the predetermined image point position for obtaining the tilt of the imaging optical system; and A fourth acquisition unit configured to acquire a second image stabilization driving amount of an image stabilization unit during image stabilization, the image stabilization unit being configured to perform image stabilization, wherein the fourth acquisition unit includes: An imaging device configured to acquire the second image stabilization driving amount associated with the predetermined image point position by using information capable of being used to acquire an amount of movement of the predetermined image point position for obtaining tilt of the imaging optical system.

22. A control method for acquiring an image stabilization driving amount of an image stabilization optical system during image stabilization, the image stabilization optical system being configured to perform image stabilization, the control method comprising: acquiring information on image shift sensitivity from a storage unit storing an image stabilization coefficient table as information on image shift sensitivity of respective image point positions with respect to decentration of the image stabilization optical system provided in the imaging optical system, the image stabilization coefficient table including image stabilization coefficient information in a matrix format associated with the image point position, the image stabilization coefficient information including decentered image shift sensitivity and position information of the image point position; and acquiring the image stabilization driving amount of the image stabilization optical system associated with the predetermined image point position by using the information on the image shift sensitivity associated with the predetermined image point position.

23. A non-transitory computer-readable storage medium storing a computer program that causes a computer to execute the control method according to claim 22.

Images