JP2020184027A - Image tremor correction device and method, and imaging device - Google Patents

Abstract

To compensate for an impact of a self-weight falling of a tremor-proof element in various attitudes.SOLUTION: An image tremor correction device has: acquisition means that shifts in a plane vertical to an optical axis, and thereby acquires an amount of self-weight falling of a first element; control means that shifts in the plane vertical to the optical axis, and thereby controls a second element so as to correct the image tremor; and detection means that detects an attitude, in which the control means is configured to determine an offset direction and amount of offset of a drive center of the second element from a reference position on the basis of the amount of self-weight falling in the attitude detected by the detection means.SELECTED DRAWING: Figure 2

Description

The present invention relates to an image blur correction device and method, and an image pickup device.

In recent years, image blur correction mechanisms have been installed in many imaging devices and photographing lenses due to the high performance of imaging devices. The image blur correction mechanism can reduce the influence of camera shake on the captured image when the image pickup device is hand-held for shooting.

Several types of blur correction mechanisms have been proposed for driving the vibration isolation element used in the image sensor. For example, a method for driving a part of the lens of the photographing optical system or a method for driving the image sensor. It has been known. The method of driving a part of the lens of the photographic optical system is to drive a part of the lens of the photographic optical system in the lens barrel to correct the image blur. Hereinafter, the image blur correction mechanism by this method will be used. It is called "lens vibration isolation mechanism". Further, the method of driving the image sensor is to drive the image sensor in the image sensor main body to correct the image blur, and hereinafter, the image blur correction mechanism by this method will be referred to as an "image sensor vibration isolation mechanism". Further, there is also known a method in which a lens anti-vibration mechanism and an image sensor anti-vibration mechanism are combined to drive both a part of the lens of the photographing optical system and the image sensor to correct image blur.

Two types of lens vibration isolation mechanisms are known depending on the control method. One is a driving method in which a position detection device is mounted on a driving lens unit (hereinafter referred to as "vibration-proof lens unit") to feedback-control the position, and the other is a position detection on the vibration-proof lens unit. This is a drive method that is controlled by an open loop without a device. In the case of open loop control, since the position of the anti-vibration lens unit cannot be detected, it is easily affected by the surrounding environment. For example, the anti-vibration lens unit is slightly displaced in the direction of gravity due to its own weight. May be affected by.

When the self-weight drop occurs, there is a problem that the movable range of the anti-vibration lens unit in the self-weight drop direction is reduced by the displacement due to the self-weight drop, and the performance in image blur correction is deteriorated. In addition, the anti-vibration lens unit is displaced with respect to the design value of the optical axis of the photographing optical system due to the drop in its own weight, so that image quality deterioration such as large aberrations occur at a position where the image height is high during shooting. There are also challenges.

On the other hand, the lens vibration isolation mechanism using open loop control has an advantage that it can be configured at a relatively low cost because it does not use a position detection device.

In Patent Document 1, as a countermeasure against the self-weight drop of the anti-vibration lens unit as described above, the drive lens unit is displaced upward by gravity by using a magnet provided in the vicinity of the image blur correction means to cancel the self-weight drop. The technology is disclosed.

Japanese Unexamined Patent Publication No. 2013-254184

However, in the method of Patent Document 1, if the weight drops in the direction in which the magnet can be arranged, the weight drop can be canceled, but if the direction of the weight drop changes due to a change in the posture of the imaging device or the like. , It is difficult to cancel the weight drop. For example, if the magnet is provided in all directions around the anti-vibration lens unit, or if the magnet can be driven around the optical axis in the direction of its own weight drop, it is possible to cancel the own weight drop. .. However, it is disadvantageous from the viewpoint of cost to provide these mechanisms for canceling the weight drop, so it is difficult to cancel the weight drop in all directions by applying the method shown in Patent Document 1. ..

The present invention has been made in view of the above problems, and an object of the present invention is to compensate for the influence of the weight drop of the vibration isolator in various postures.

In order to achieve the above object, the image blur correction device of the present invention includes an acquisition means for acquiring the amount of weight loss of the first element that corrects image blur by shifting in a plane perpendicular to the optical axis, and the light. It has a control means for controlling the second element so as to correct image blur by shifting in a plane perpendicular to the axis, and a detection means for detecting the posture, and the control means detects by the detection means. It is characterized in that the offset direction and the offset amount from the reference position of the drive center of the second element are determined based on the self-weight drop amount in the determined posture.

According to the present invention, it is possible to compensate for the influence of the weight drop of the vibration isolator in various postures.

The perspective view which shows the appearance of the image pickup apparatus and a lens barrel in an embodiment of this invention. A cross-sectional view of the imaging system according to the embodiment and a block diagram showing a schematic functional configuration. The figure explaining the structure of the image sensor anti-vibration part in embodiment. The figure explaining the structure of the lens vibration isolation part in embodiment. The figure explaining the control method of the vibration isolation part of an image sensor for reducing the bias of the vibration isolation range in embodiment. The figure explaining the control of the vibration isolation part of an image sensor for reducing the deterioration of image quality at the peripheral image height in embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiment, not all of the plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the attached drawings, the same or similar configurations are designated by the same reference numbers, and duplicate description is omitted.

FIG. 1A is a perspective view showing the appearance of the camera body 1 which is an imaging device in the imaging system of the present embodiment, and FIG. 1B shows the appearance of the lens barrel 2 in the imaging system of the present embodiment. It is a perspective view. 2 (a) is a cross-sectional view of the image pickup apparatus provided with the image blur correction mechanism of the present embodiment, and FIG. 2 (b) is a block diagram showing an electrical configuration.

When the lens barrel 2 is attached to the camera body 1, the camera body 1 and the lens barrel 2 are electrically connected via the electrical contact 14a on the camera body 1 side and the electrical contact 14b on the lens barrel 2 side. Will be done. In the present embodiment, a so-called interchangeable lens type camera in which the lens barrel 2 is detachable from the camera body 1 will be described, but the present invention is not limited to this, and the lens barrel is attached to the camera body 1. It can also be applied to an imaging device in which 2 is fixed.

The lens barrel 2 has a photographing optical system 3 composed of a plurality of lenses, and the anti-vibration lens unit 19 (optical element) is included in the photographing optical system 3. Further, the lens barrel 2 is a lens that corrects image blur by driving a lens system control unit 15, a lens-side operation unit 16, a lens-side blur detection unit 17 that detects the amount of blur in the imaging system, and an anti-vibration lens unit 19. It has a vibration isolator 18. In addition to the anti-vibration lens unit 19, the lens system control unit 15 also drives a focus lens (not shown) included in the photographing optical system 3, a diaphragm, and the like.

The camera body 1 has, for example, an image sensor unit 6 including an image sensor such as a CMOS sensor, and the image sensor unit 6 is provided so as to be driveable in a plane perpendicular to the optical axis 4 of the photographing optical system 3. Further, the camera body 1 includes a camera system control unit 5 that controls the entire image pickup system, an image processing unit 7 that processes an image signal obtained from an image sensor, a memory 8 that stores the processed image, a processed image, and the like. It has a display unit 10 for displaying / reproducing an image stored in the memory 8. It also includes a camera-side operation unit 9 that receives instructions from the user. The display unit 10 includes a rear display device, a small display panel (not shown) for displaying shooting information provided on the upper surface of the camera body 1, and an electronic viewfinder (also called an EVF) (not shown).

Further, the camera body 1 corrects image blur by driving an attitude detection unit 11 that detects the posture of the camera body 1 in the direction of gravity, a camera-side blur detection unit 12 that detects the amount of blur of the image pickup system, and an image sensor unit 6. The image sensor vibration isolator 13 is included.

The camera-side blur detection unit 12 and the lens-side blur detection unit 17 can detect rotation with respect to the optical axis 4 applied to the image pickup system, and can be realized by using, for example, a vibration gyro. The image sensor vibration isolation unit 13 drives the image pickup element unit 6 that functions as a vibration isolation element, and the lens vibration isolation unit 18 drives the vibration isolation lens unit 19 that functions as a vibration isolation element in a plane perpendicular to the optical axis 4, respectively (shift). ), And the specific configuration will be described later.

The anti-vibration lens unit 19 and the lens anti-vibration unit 18 form a first optical anti-vibration mechanism, and the image sensor unit 6 and the image sensor anti-vibration unit 13 form a second optical anti-vibration mechanism.

In the imaging system having the above configuration, the light from the subject is incident through the photographing optical system 3, is imaged on the imaging surface of the imaging element included in the imaging element unit 6, and the signal obtained by photoelectric conversion is obtained. It is output.

The image processing unit 7 has an A / D converter, a white balance adjustment circuit, a gamma correction circuit, an interpolation calculation circuit, a color interpolation processing circuit, and the like inside, and performs predetermined pixel interpolation processing and color conversion processing for recording. Image data for display and image data for display are generated. The color interpolation calculation circuit performs color interpolation (demosiking) processing from the signals of the Bayer array to generate a color image. Further, the image processing unit 7 compresses an image, a moving image, a sound, or the like by using a predetermined method. Further, since the image processing unit 7 can generate a blur detection signal based on the comparison between a plurality of images obtained from the image sensor, the camera side blur detection unit 12 is formed by the image sensor and the image processing unit 7. May be configured.

The memory 8 includes a storage unit, and the camera system control unit 5 outputs to the recording unit of the memory 8 and displays an image to be presented to the user on the display unit 10.

The camera system control unit 5 responds to an external operation from the camera-side operation unit 9 to generate and output a timing signal or the like at the time of imaging, and controls the imaging system, the image processing system, and the recording / reproducing system, respectively. For example, the camera system control unit 5 detects the pressing of the shutter release button included in the camera-side operation unit 9, and controls the drive of the image sensor of the image sensor unit 6, the operation of the image processing unit 7, the compression processing, and the like. Further, the display unit 10 controls the state of each segment of the information display device that displays information. The rear display device included in the display unit 10 may be a touch panel, and may also serve as the display unit 10 and the camera-side operation unit 9.

An image processing unit 7 is connected to the camera system control unit 5, and a focus evaluation value and brightness are obtained from a signal obtained from the image sensor of the image sensor unit 6, and an appropriate focus lens position is obtained based on these values. And the amount of drawing. Then, the camera system control unit 5 notifies the lens system control unit 15 of an appropriate focus lens position and aperture amount via the electrical contact 14b. The lens system control unit 15 receives a notification via the electrical contact 14a and drives the focus lens and the diaphragm included in the photographing optical system 3 to obtain an appropriate amount of subject light in the vicinity of the image sensor of the image sensor unit 6. Can be imaged with.

Further, in the mode of performing blur correction, the image sensor vibration isolator 13 and the lens vibration isolator 18 are appropriately controlled based on the signals obtained from the camera side blur detection unit 12 and the lens side blur detection unit 17. As a specific control method, first, the camera system control unit 5 and the lens system control unit 15 detect the camera shake signal detected by the camera side blur detection unit 12 and the lens side blur detection unit 17, respectively. Based on the result, the driving amount of the image sensor unit 6 and the anti-vibration lens unit 19 for correcting the image blur is calculated. After that, the calculated drive amount is sent to the image sensor anti-vibration unit 13 and the lens anti-vibration unit 18 as command values to drive the image sensor unit 6 and the anti-vibration lens unit 19, respectively.

In this way, by controlling the operation of each part of the camera system in response to the user operation on the camera side operation unit 9, it is possible to shoot a still image and a moving image.

Second Optical Vibration Isolation Mechanism Next, the configuration of the second optical vibration isolation mechanism including the image pickup element vibration isolation unit 13 and the image pickup element unit 6 in the present embodiment will be described with reference to FIG. FIG. 3A is a schematic view of the second optical vibration isolation mechanism when viewed from the object side of the optical axis 4, and FIG. 3B is the second optical vibration isolation mechanism in FIG. 3A. It shows the cross-sectional view in the AA cross section of.

In FIG. 3, the fixing portion 31 of the image sensor vibration isolation portion 13 is composed of a front fixing portion 31a on the object side with respect to the movable portion 32 and a rear fixing portion 31b on the opposite side to the movable portion 32, and is formed on the camera body 1. On the other hand, it is fixed. Further, the fixed portion 31 is provided with drive magnets 33a to 33c, and the movable portion 32 is provided with drive coils 34a to 34c so as to correspond to the drive magnets 33a to 33c, respectively. Then, when the image sensor unit 6 is driven, the image sensor vibration isolator 13 is generated by the Lorentz force generated by the magnetic field formed by the drive magnets 33a to 33c and the current flowing when the drive coils 34a to 34c are energized. Is driven in a plane perpendicular to the optical axis 4. In this way, image blurring can be corrected by driving the movable portion 32 provided with the image sensor unit 6 relative to the fixed portion 31.

The position detection units 35a to 35c are composed of Hall elements, are arranged inside the drive coils 34a to 34c, and detect the relative position of the movable portion 32 with respect to the fixed portion 31 as follows. That is, the magnetic flux received by the drive magnets 33a to 33c changes with the relative displacement of the drive coils 34a to 34c with respect to the drive magnets 33a to 33c. The position detection units 35a to 35c detect the relative positions of the drive magnets 33a to 33c by detecting the amount of change thereof.

The rolling ball 36 is provided between the fixed portion 31 and the movable portion 32 to reduce friction during relative movement of both. The yoke 37 controls the magnetic field generated by the driving magnets 33a to 33c.

In the present embodiment, the drive magnets 33a to 33c and the position detection units 35a to 35c are used to detect the relative position of the movable portion 32, but the present invention is not limited to this. For example, the position detection units 35a to 35c are provided at positions different from the drive coils 34a to 34c, and another position detection magnet is provided exclusively at the position of the fixed portion 31 facing the position detection units 35a to 35c. It doesn't matter.

The movable portion 32 can be driven in the lateral direction of the paper surface from the drive magnet 33a and the drive coil 34a, and the relative position of the movable portion 32 in the lateral direction of the paper surface can be detected by using the position detection unit 35a. .. Similarly, by using the driving magnets 33b and 33c and the driving coils 34b and 34c, the movable portion 32 can be driven in the vertical direction of the paper surface, and by using the position detecting portions 35b and 35c, the movable portion 32 can be driven in the vertical direction of the paper surface. The relative position of the movable portion 32 can be detected. Although not shown, by providing another set of a drive magnet, a drive coil, and a position detection unit in the vertical direction of the paper surface, it is possible to drive in the rotation direction centered on the optical axis 4.

The image sensor vibration isolation unit 13 controls a desired movement by performing feedback control based on the detection results of the position detection units 35a to 35c provided as described above. Therefore, the downward displacement of gravity due to the drop of its own weight (drop of its own weight) can be canceled by feedback control according to the output of the position detection units 35a to 35c.

First Optical Anti-Vibration Mechanism Next, the configuration of the first optical anti-vibration mechanism including the lens anti-vibration unit 18 and the anti-vibration lens unit 19 in the present embodiment will be described with reference to FIG. FIG. 4A is a schematic view of the first optical vibration isolation mechanism when viewed from the object side of the optical axis 4, and FIG. 4B is the first optical vibration isolation mechanism in FIG. 4A. It shows the cross-sectional view of the BB cross section of. Further, FIG. 4C shows a case where the anti-vibration lens unit 19 drops its own weight due to the influence of gravity in FIG. 4B, which is a cross section of BB.

In FIG. 4, the fixing portion 41 in the lens anti-vibration portion 18 is composed of a front fixing portion 41a on the object side with respect to the movable portion 42 and a rear fixing portion 41b on the opposite side to the movable portion 42, with respect to the lens barrel 2. Is fixed. Further, the movable portion 42 is provided with drive magnets 43a and 43b, and the fixed portion 41 is provided with drive coils 44a and 44b so as to correspond to the drive magnets 43a and 43b, respectively. When the anti-vibration lens unit 19 is driven, the lens anti-vibration unit 18 is lighted by the magnetic field formed by the driving magnets 43a and 43b and the Lorentz force generated by the current flowing when the driving coil 44 is energized. It is driven in a plane perpendicular to the axis 4. In this way, image blurring can be corrected by driving the movable portion 42 provided with the anti-vibration lens unit 19 relative to the fixed portion 41.

Then, the pulling spring 45 that engages the movable portion 42 and the fixing portion 41 causes the movable portion 42 to stand still at a position in equilibrium with the fixing portion 41. The rolling ball 46 is provided between the fixed portion 41 and the movable portion 42, and reduces friction during relative movement of both. The yoke 47 controls the magnetic field generated by the driving magnets 43a and 43b.

In the present embodiment, the lens vibration isolator 18 does not have a position detection unit unlike the image sensor vibration isolator 13. That is, so-called open-loop control is performed in which the lens vibration isolator 18 is controlled only for the detection result of the lens-side blur detection unit 17 without detecting and feeding back the relative position of the movable unit 42 with respect to the fixed unit 41. I'm taking it. Therefore, for example, when the anti-vibration lens unit 19 receives a force in the direction of gravity due to its own weight, it stands still at a position where the force due to its own weight and the tension due to the tension spring 45 are balanced. That is, a minute displacement (falling of its own weight) occurs due to the force in the direction of gravity due to its own weight.

FIG. 4C shows the movable portion 42 of the lens anti-vibration portion 18 when the weight drops when the lower part of the paper surface is in the direction of gravity, and the arrow 49 indicates the amount of the weight drop with respect to the optical axis 4. Represents. When the self-weight drop occurs, the lens anti-vibration unit 18 narrows the movable range in which the anti-vibration lens unit 19 can be driven in the downward direction of gravity. Further, when the weight drop amount is 49 minutes and the center of the anti-vibration lens unit 19 is deviated from the optical axis 4, there is a possibility that adverse effects on image quality such as an increase in aberration and a decrease in the amount of light in the periphery may occur.

As described above, the lens vibration isolator using the open loop control can be inexpensively configured because the position detection unit is not used, but problems such as a decrease in the movable range and a decrease in image quality may occur.

● Adjustment of anti-vibration range Next, using FIG. 5, when the weight of the anti-vibration lens unit 19 drops, the image sensor anti-vibration unit 13 and the lens anti-vibration unit 18 are used to determine the bias of the anti-vibration range. The method of mitigation will be described. FIG. 5 is a diagram illustrating a control method of the image sensor vibration isolation unit 13 for reducing the bias of the vibration isolation range in the present embodiment when the weight of the vibration isolation lens unit 19 drops. FIG. 5A is a diagram showing a configuration when the anti-vibration lens unit 19 has a negative power (for example, a concave lens), and FIG. 5B is a diagram showing a configuration when the anti-vibration lens unit 19 has a positive power. It is a figure which showed the structure in the case of having (for example, a convex lens). Note that FIG. 5 shows only the image sensor unit 6 and the vibration-proof lens unit 19 in the image pickup system of the present embodiment for the sake of simplification of the description. Further, in FIG. 5, it is assumed that gravity is applied in the downward direction on the paper surface. Further, in FIG. 5, the optical axis 4 is the design center (reference position) of the anti-vibration lens unit 19 and the image sensor unit 6.

FIG. 5A shows the anti-vibration lens unit 19 when its own weight drops, and the broken line 52 indicates the upper end of the movable range of the anti-vibration lens unit 19 (hereinafter, referred to as “lens upper movable end”). , Dashed line 53 represents a lower end (hereinafter, referred to as a “lens lower movable end”). The alternate long and short dash line 54 represents the drive center of the anti-vibration lens unit 19 when the anti-vibration lens unit 19 drops its own weight, and the arrow 55 represents the amount of its own weight drop. The arrow 56 represents the distance to the lower movable end 53 of the lens when the anti-vibration lens unit 19 drops its own weight, that is, the lower movable range (hereinafter, referred to as “lens lower movable range”). Similarly, the arrow 57 represents the distance to the upper movable end 52 of the lens, that is, the upper movable range (hereinafter, referred to as “the upper movable range of the lens”) when the anti-vibration lens unit 19 drops its own weight. Further, the arrow 58 represents the lower movable range of the lens when the anti-vibration lens unit 19 does not drop its own weight, and the arrow 59 represents the upper movable range of the lens at that time.

Further, as shown in FIG. 5A, the lens lower movable range 56 when the anti-vibration lens unit 19 drops its own weight is shorter than the lens lower movable range 58 when its own weight does not drop. On the other hand, the movable range 57 on the upper side of the lens when the anti-vibration lens unit 19 drops its own weight is longer than the movable range 59 on the upper side of the lens when the weight does not drop.

In this way, the lower movable range 56 of the lens becomes shorter than the upper movable range 57 of the lens due to the weight drop of the anti-vibration lens unit 19, so that when the image blur is corrected, the image blur is corrected in the direction of gravity. It is possible that the performance of blur correction will be different.

On the other hand, in the present embodiment, the difference in the vertical movable range of the vibration-proof lens unit 19 is reduced by changing the drive center of the image sensor unit 6 by the image sensor vibration-proof unit 13. In FIG. 5A, the broken line 62 is the upper end of the movable range of the image sensor unit 6 (hereinafter, referred to as “the upper movable end of the image sensor”), and the broken line 63 is the lower end (hereinafter, “below the image sensor”). It is called a "side movable end"). The alternate long and short dash line 64 represents the drive center of the image sensor unit 6 that is set when the anti-vibration lens unit 19 drops its own weight, and the arrow 65 indicates the offset amount from the design center (that is, the optical axis 4) which is the reference position. Represents. The arrow 66 indicates the distance to the lower movable end 63 of the image sensor when the image sensor unit 6 is offset from the design center, that is, the lower movable range (hereinafter, referred to as “the lower movable range of the image sensor”). Represents. Similarly, the arrow 67 indicates the distance to the upper movable end 62 of the image sensor when the image sensor unit 6 is offset from the design center, that is, the upper movable range (hereinafter, referred to as “the upper movable range of the image sensor”). Represents. Further, the arrow 68 represents the lower movable range of the image sensor when the image sensor unit 6 is not offset from the design center, and the arrow 69 represents the upper movable range of the image sensor at that time.

In this way, the drive center of the image sensor unit 6 is offset downward from the design center by gravity so as to be represented by the alternate long and short dash line 64. As a result, the movable range 67 on the upper side of the image sensor can be made larger than the movable range 66 on the lower side of the image sensor, and the bias of the vibration-proof range due to the weight drop of the vibration-proof lens unit 19 can be reduced. That is, when the anti-vibration lens unit 19 drops its own weight, the drive center of the image sensor unit 6 is offset from the design center according to the amount of its own weight drop 55, thereby reducing the bias of the anti-vibration range due to the self-weight drop. It becomes possible to do.

In FIG. 5A, since the lens constituting the anti-vibration lens unit 19 is a lens having a negative power, for example, when the anti-vibration lens unit 19 is driven downward by gravity, an image is displayed on the image sensor. Move upward in gravity. Therefore, in order to reduce the decrease in the vibration isolation range in the gravity direction due to the weight drop of the vibration isolation lens unit 19, the image sensor upper movable range 67 is movable below the image sensor when the image sensor unit 6 moves upward in gravity. Make it longer than the range 66.

FIG. 5B is a diagram when the anti-vibration lens unit 19 shown in FIG. 5A has a positive power, and the offset direction from the design center, which is the reference position of the image sensor unit 6, is FIG. In principle, the same operation is performed except that the case of (a) is reversed.

FIG. 5B shows the anti-vibration lens unit 19 when its own weight drops, the broken line 72 represents the upper movable end of the lens of the anti-vibration lens unit 19, and the broken line 73 represents the lower movable end of the lens. ing. The alternate long and short dash line 74 represents the drive center of the anti-vibration lens unit 19 when the anti-vibration lens unit 19 drops its own weight, and the arrow 75 represents the amount of its own weight drop. The arrow 76 indicates the movable range on the lower side of the lens when the anti-vibration lens unit 19 drops its own weight, and the arrow 77 indicates the movable range on the upper side of the lens when the anti-vibration lens unit 19 also drops its own weight. Further, the arrow 78 represents the lower movable range of the lens when the anti-vibration lens unit 19 does not drop its own weight, and the arrow 79 represents the upper movable range of the lens at that time.

Further, in FIG. 5B, the broken line 82 represents the upper movable end of the image sensor of the image sensor unit 6, and the broken line 83 represents the lower movable end of the image sensor. The alternate long and short dash line 84 represents the drive center of the image sensor unit 6 that is set when the anti-vibration lens unit 19 drops its own weight, and the arrow 85 represents the offset amount from the design center (that is, the optical axis 4). The arrow 86 indicates the lower movable range of the image sensor when the image sensor unit 6 is offset from the design center, and the arrow 87 indicates the upper movable range of the image sensor at that time. Further, the arrow 88 represents the movable range on the lower side of the image sensor when the image sensor unit 6 is not offset from the design center, and the arrow 89 represents the drive stroke on the upper side of the image sensor at that time.

In the case of FIG. 5B, since the lens constituting the anti-vibration lens unit 19 is a lens having positive power, for example, when the anti-vibration lens unit 19 is driven downward by gravity, the image is gravity even on the image sensor. Move down. Therefore, in order to reduce the decrease in the movable range in the gravity direction due to the weight drop of the anti-vibration lens unit 19, the lower movable range 86 of the image sensor when the image sensor unit 6 moves downward in gravity is set to the upper movable range of the image sensor. Make it longer than 87.

Therefore, as can be seen from FIG. 5, the offset direction and the offset amount from the design center of the image sensor unit 6 are adjusted according to the weight drop amount of the anti-vibration lens unit 19, the attitude detection unit 11, and the lens power of the anti-vibration lens unit 19. To determine.

As a method of setting the offset amount 65 from the design center of the image sensor unit 6 when the anti-vibration lens unit 19 drops its own weight, first, the amount of its own weight drop is stored in the lens barrel 2. Then, when the lens barrel 2 is attached to the camera body 1, a method of reading and acquiring the lens barrel 2 can be considered.

Further, in the present embodiment, the direction of gravity is described as below the paper surface, but the direction of gravity is detected by the output of the posture detection unit 11, and the offset direction and offset amount from the design center of the image sensor unit 6 are determined according to the result. Should be changed.

Further, in the present embodiment, a method of reducing all the influence of the self-weight drop of the anti-vibration lens unit 19 by driving the image sensor unit 6 has been described, but the present invention is not limited to this. Only a part of it may be supplemented by driving the image sensor unit 6, and the rest may be supplemented by driving the anti-vibration lens unit 19. That is, according to the output of the attitude detection unit 11, the movable range of the effect of dropping the weight of the anti-vibration lens unit 19 is partially shifted from the optical axis 4 by shifting the drive center of the image sensor unit 6, and the rest is the anti-vibration lens. It may be realized by driving the unit 19 itself above gravity. In either case, the correction for the deviation of the anti-vibration lens unit 19 from the optical axis 4 is realized by offsetting the drive center of the image sensor unit 6 from the design center. That is, the reduction in the anti-vibration range due to the unbalanced movable range of the anti-vibration lens unit 19 may be compensated for by changing the movable range of the image sensor unit 6.

● Reduction of influence on image quality Next, using FIG. 6, when the weight of the anti-vibration lens unit 19 drops, the image sensor anti-vibration unit 13 and the lens anti-vibration unit 18 are used to reduce the deterioration of image quality. The method of doing this will be described. As described above, when the weight of the anti-vibration lens unit 19 drops, there is a possibility that the image quality may be adversely affected, such as an increase in peripheral aberrations and a decrease in the amount of light. Here, a method for reducing such deterioration in image quality will be described.

FIG. 6 is a diagram illustrating a control method of the image sensor vibration isolation unit 13 for reducing deterioration of image quality in the present embodiment when the weight of the vibration isolation lens unit 19 drops. FIG. 6A is a diagram showing a configuration when the anti-vibration lens unit 19 has a negative power (for example, a concave lens), and FIG. 6B is a diagram showing a configuration when the anti-vibration lens unit 19 has a positive power. It is a figure which showed the structure in the case of having (for example, a convex lens). Note that FIG. 6 shows only the image sensor unit 6 and the anti-vibration lens unit 19 in the image pickup system of the present embodiment for the sake of simplification of the description as in FIG. Further, in FIG. 6, it is assumed that gravity is applied in the downward direction on the paper surface. Further, in FIG. 6, similarly to FIG. 5, the optical axis 4 is the design center of the anti-vibration lens unit 19 and the image sensor unit 6.

FIG. 6A shows the anti-vibration lens unit 19 when its own weight drops, and 52 to 57 are the same as those shown in FIG. 5A, so description thereof will be omitted here.

As shown in FIG. 6A, when the anti-vibration lens unit 19 drops by its own weight, the optical axis 4 does not pass through the drive center 154 of the anti-vibration lens unit 19, so that the light passing through the optical axis 4 does not pass through. An image is formed on the image sensor at a position offset from the optical axis 4. In FIG. 6A, the light passing through the optical axis 4 changed by the anti-vibration lens unit 19 when its own weight drops is represented by the alternate long and short dash line 160. In this way, due to the self-weight drop of the anti-vibration lens unit 19, the light passing through the optical axis 4 changes so as to bend upward in gravity like the alternate long and short dash line 160. Therefore, especially at a position where the image height below gravity is high. Image quality may deteriorate, such as an increase in aberration and a decrease in the amount of light.

On the other hand, in the present embodiment, the influence of image quality deterioration is reduced by changing the drive center of the image sensor unit 6 by the image sensor vibration isolation unit 13. In FIG. 6A, the broken line 162 represents the upper movable end of the image sensor of the image sensor unit 6, and the broken line 163 represents the lower movable end of the image sensor. The alternate long and short dash line 164 represents the drive center of the image sensor unit 6 that is set when the anti-vibration lens unit 19 drops its own weight, and the arrow 165 is the offset amount from the design center (that is, the optical axis 4) which is the reference position. Represents. The arrow 166 represents the movable range on the lower side of the image sensor when the image sensor unit 6 is offset. Similarly, the arrow 167 indicates the movable range on the upper side of the image sensor when the image sensor unit 6 is offset. Represents. Further, the arrow 168 represents the lower movable range of the image sensor when the image sensor unit 6 is not offset from the design center, and the arrow 169 represents the upper movable range of the image sensor at that time.

In this way, the drive center of the image sensor unit 6 is offset upward from the design center by gravity so as to be represented by the alternate long and short dash line 164. As a result, by using the optical axis 4 bent by the anti-vibration lens unit 19 as the drive center of the image sensor unit 6, it is possible to reduce the deterioration of image quality due to the weight loss of the anti-vibration lens unit 19. That is, when the anti-vibration lens unit 19 drops its own weight, the drive center of the image sensor unit 6 is offset from the design center according to the amount of its own weight drop 55, thereby reducing the deterioration of image quality due to the drop in its own weight. Is possible.

In FIG. 6A, since the lens constituting the anti-vibration lens unit 19 is a lens having a negative power, for example, when the anti-vibration lens unit 19 is driven downward by gravity, an image is displayed on the image sensor. Move upward in gravity. Therefore, in order to reduce the deterioration of the image quality due to the weight drop of the anti-vibration lens unit 19, the image sensor unit 6 is offset upward by gravity.

FIG. 6B is a diagram when the anti-vibration lens unit 19 shown in FIG. 6A has a positive power, and the offset direction of the image sensor unit 6 from the design center is FIG. 6A. In principle, the operation is the same, only the opposite of the case.

FIG. 6B shows the anti-vibration lens unit 19 when the lens unit is dropped by its own weight, and 72 to 77 are the same as those shown in FIG. 6A, and thus the description thereof will be omitted here.

Further, in FIG. 6B, the broken line 182 represents the upper movable end of the image sensor of the image sensor unit 6, and the broken line 183 represents the lower movable end of the image sensor. The alternate long and short dash line 184 represents the drive center of the image sensor unit 6 that is set when the anti-vibration lens unit 19 drops its own weight, and the arrow 185 represents the offset amount from the design center. The arrow 186 indicates the lower movable range of the image sensor when the image sensor unit 6 is offset from the design center, and the arrow 187 indicates the upper movable range of the image sensor at that time. Further, the arrow 188 represents the lower movable range of the image sensor when the image sensor unit 6 is not offset from the design center, and the arrow 189 represents the upper movable range of the image sensor at that time.

In the case of FIG. 6B, since the lens constituting the anti-vibration lens unit 19 is a lens having positive power, for example, when the anti-vibration lens unit 19 is driven downward by gravity, the image is gravity even on the image sensor. Move down. Therefore, in order to reduce the deterioration of the image quality due to the weight drop of the anti-vibration lens unit 19, the image sensor unit 6 is offset downward by gravity.

Therefore, as can be seen from FIG. 6, the offset direction and the offset amount from the design center of the image sensor unit 6 are adjusted according to the weight drop amount of the anti-vibration lens unit 19, the attitude detection unit 11, and the lens power of the anti-vibration lens unit 19. To determine.

In the case of FIG. 6, as in the case of FIG. 5, as a method of setting the offset amount 165 of the image sensor unit 6 when the anti-vibration lens unit 19 drops its own weight, first, the amount of its own weight dropped on the lens barrel 2. Remember. Then, when the lens barrel 2 is attached to the camera body 1, a method of reading and acquiring the lens barrel 2 can be considered.

Further, in the present embodiment, the direction of gravity is described as below the paper surface, but the direction of gravity is detected by the output of the posture detection unit 11, and the offset direction and offset amount from the design center of the image sensor unit 6 are determined according to the result. Should be changed.

Further, in the present embodiment, a method of reducing all the influence of the self-weight drop of the anti-vibration lens unit 19 by driving the image sensor unit 6 has been described, but the present invention is not limited to this. Only a part of it may be supplemented by driving the image sensor unit 6, and the rest may be supplemented by driving the anti-vibration lens unit 19. That is, according to the output of the attitude detection unit 11, the image quality deterioration correction due to the effect of the self-weight drop of the anti-vibration lens unit 19 is partially shifted by shifting the drive center of the image sensor unit 6 from the optical axis 4, and the rest is prevented. It may be realized by driving the oscillating lens unit 19 itself upward in gravity. In either case, the correction for the deviation of the anti-vibration lens unit 19 from the optical axis 4 is realized by offsetting the drive center of the image sensor unit 6 from the design center. That is, the deterioration in image quality due to the drop in the weight of the anti-vibration lens unit 19 may be corrected by the offset of the drive center of the image sensor unit 6.

● Adjustment of vibration isolation range and proper use of mitigation of influence on image quality As described above using FIGS. 5 and 6, by offsetting the movable center of the image sensor unit 6, the vibration isolation lens unit 19 is driven by its own weight drop. It is possible to reduce the reduction of stroke and the deterioration of image quality. However, as can be seen by comparing FIGS. 5 and 6, the directions in which the image sensor unit 6 is moved are opposite in the case of reducing the bias of the movable range and the case of reducing the deterioration of the image quality. Therefore, it is difficult to obtain both effects at the same time.

Therefore, it is preferable to use the case where the vibration isolation range is prioritized and the case where the image quality is prioritized according to the shooting conditions. Hereinafter, specific examples of selective usage will be described when the adjustment of the vibration isolation range is prioritized as shown in FIG. 5 and when the reduction of the influence on the image quality is prioritized as shown in FIG. 6 according to the shooting conditions.

(I) Selection according to the focal length A case where the correction method is used properly according to the focal length determined by the photographing optical system 3 will be described.

In general, it is known that the longer the focal length, the larger the amount of image blurring, and it is desirable that the vibration isolation range is wide when performing image blurring correction. Therefore, when the focal length is longer than the predetermined focal length, the vibration isolation range is prioritized and the image sensor unit 6 is driven as described with reference to FIG. That is, the offset direction and the offset amount from the design center of the image sensor unit 6 are determined according to the amount of the self-weight drop of the anti-vibration lens unit 19, the posture detected by the posture detection unit 11, and the focal length of the photographing optical system 3. To do.

(Ii) Selection according to shutter speed (exposure time) Next, a case where the correction method is used properly according to the shutter speed set by the user by the camera system control unit 5 and the camera side operation unit 9 will be described.

In general, the longer the exposure time, the larger the amount of image blurring tends to be. Therefore, when performing image blurring correction, it is desirable that the vibration isolation range is wide. Therefore, when the exposure time is longer than a predetermined time, the vibration isolation range is prioritized and the image sensor unit 6 is driven as described with reference to FIG. That is, the offset direction and the offset amount from the design center of the image sensor unit 6 are determined according to the amount of the self-weight drop of the anti-vibration lens unit 19, the posture detected by the posture detection unit 11, and the exposure time of the image sensor.

(Iii) Different use according to the aperture value Next, a case where the correction method is properly used according to the aperture value set by the user by the camera system control unit 5 and the camera side operation unit 9 will be described.

In general, the smaller the aperture value, that is, the larger the aperture of the aperture, the greater the influence of aberrations in the periphery, and the greater the amount of decrease in the amount of peripheral light. Therefore, the drive center of the image sensor does not move away from the optical axis 4. However, it is desirable because the deterioration of the image quality is suppressed. Therefore, when the aperture of the diaphragm is larger than the predetermined aperture, the image quality is prioritized and the image sensor unit 6 is driven as described with reference to FIG. That is, it is preferable to allocate the movable range of the image sensor unit 6 according to the amount of weight drop of the anti-vibration lens unit 19, the posture detected by the posture detection unit 11, and the aperture value (opening).

In this way, the control shown in FIG. 5 and the control shown in FIG. 6 are selectively used according to the shooting conditions such as the focal length, the shutter speed, and the aperture value.

As described above, according to the present embodiment, even when the direction of gravity changes due to a change in posture, the decrease in the anti-vibration range due to the drop of the own weight of the anti-vibration lens unit can be reduced, or the peripheral image of the image can be reduced. It is possible to reduce the deterioration of image quality at high altitude.

In the above example, the case where the lens-side blur detection unit 17 controls the vibration-proof lens unit 19 by open-loop control has been described. However, the lens-side blur detection unit 17 has a position detection unit, and the image sensor vibration-proof unit 17 has a position detection unit. 13 may control the image sensor unit 6 by open loop control. In that case, the same effect can be obtained by reversing the control of the image sensor unit 6 and the control of the anti-vibration lens unit 19 described above.

<Other embodiments>
The present invention also supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and one or more processors in the computer of the system or device implement the program. It can also be realized by the process of reading and executing. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

The invention is not limited to the above embodiments, and various modifications and modifications can be made without departing from the spirit and scope of the invention. Therefore, a claim is attached to make the scope of the invention public.

1: Camera body 2: Lens lens barrel 3: Imaging optical system 4: Optical axis, 6: Imaging element unit, 9: Camera side operation unit, 11: Attitude detection unit, 12: Camera shake detection unit, 13: Imaging Element vibration isolation unit, 15: lens system control unit, 16: lens side operation unit, 17: lens side blur detection unit, 18: lens vibration isolation unit, 35a to 35c: position detection unit

Claims (17)

An acquisition means for acquiring the amount of weight loss of the first element that corrects image blurring by shifting in a plane perpendicular to the optical axis, and
A control means for controlling the second element so as to correct image blur by shifting in a plane perpendicular to the optical axis.
Has a detection means for detecting posture,
The control means determines the offset direction and the offset amount of the drive center of the second element from the reference position based on the weight drop amount in the posture detected by the detection means. Blur correction device. The control means is centered on the drive center of the second element so that the vibration isolation range corresponding to the movable range of the first element reduced by the amount of weight drop in the posture detected by the detection means is widened. The image blur correction device according to claim 1, wherein the first control for determining the offset direction and the offset amount from the reference position is performed. The control means adjusts the offset direction and the offset amount of the drive center of the second element from the reference position so as to correct the shift of the image changed by the weight drop amount in the posture detected by the detection means. The image blur correction device according to claim 1, wherein the second control for determining the determination is performed. The control means adjusts the offset direction and the offset amount of the drive center of the second element from the reference position so as to correct the shift of the image changed by the weight drop amount in the posture detected by the detection means. The image blur correction device according to claim 2, wherein the second control to be determined and the first control are selectively performed according to the shooting conditions. The image blur correction device according to any one of claims 1 to 4, wherein the driving of the first element is performed by open loop control. Further having a detecting means for detecting the position of the second element,
The image blur correction device according to any one of claims 1 to 5, wherein the control means controls the second element using a position detected by the detection means. Any one of claims 1 to 6, wherein the first element is an optical element, and the second element is an image pickup element that photoelectrically converts light incident on the optical element. The image blur correction device described in the section. Any one of claims 1 to 6, wherein the second element is an optical element, and the first element is an image pickup element that photoelectrically converts light incident on the optical element. The image blur correction device described in the section. The claim is characterized in that the control means determines the offset direction and the offset amount of the second element according to the weight drop amount, the posture detected by the detection means, and the lens power of the optical element. Item 7. The image blur correction device according to item 7. The optical element is included in a photographing optical system that forms a subject light on the image sensor.
Any one of claims 7 to 9, wherein the control means controls to perform the first control when the focal length of the photographing optical system is longer than a predetermined focal length. The image blur correction device described in the section. The method according to any one of claims 7 to 10, wherein the control means controls to perform the first control when the exposure time of the image pickup device is longer than a predetermined time. The image blur correction device described. 7. The control means is characterized in that, when the aperture of the diaphragm that controls the amount of light incident on the image sensor is larger than the predetermined aperture, the control means is controlled to perform the second control. The image blur correction device according to any one of No. 11. With the image sensor
An image pickup apparatus comprising the image blur correction apparatus according to any one of claims 1 to 12. The imaging apparatus according to claim 13, further comprising a photographing optical system including an optical element that corrects image blur by shifting in a plane perpendicular to the optical axis. An acquisition step in which the acquisition means acquires the amount of weight loss of the first element that corrects image blur by shifting in a plane perpendicular to the optical axis.
A control step in which the control means controls the second element so as to correct the image blur by shifting in a plane perpendicular to the optical axis.
The detection means has a detection process for detecting the posture.
The control means determines the offset direction and the offset amount of the drive center of the second element from the reference position based on the weight drop amount in the posture detected by the detection means. Blur correction method. A program for causing a computer to function as each means of the image blur correction device according to any one of claims 1 to 14. A computer-readable storage medium that stores the program according to claim 16.

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