JP7398907B2 - Image stabilization system and method, imaging device and imaging system - Google Patents

Description

The present invention relates to an image stabilization system and method, an imaging device, and an imaging system.

2. Description of the Related Art Various methods have been proposed for image blur correction to prevent image deterioration that may occur due to the effects of camera shake or the like when photographing with a digital camera. For example, an optical image stabilization method in which a correction lens is shifted in a direction substantially perpendicular to the optical axis, and an imaging plane image stabilization method in which an image sensor is shifted in a direction substantially perpendicular to the optical axis are known. ing. Furthermore, in Patent Document 1, an imaging system to which an interchangeable lens can be attached and detached has both an optical image stabilization means on the interchangeable lens side and an image pickup surface type image blur correction means on the camera side, and each of the image stabilization means A system has been disclosed in which image blur is corrected by driving the camera.

Japanese Patent Application Publication No. 2009-251492

However, Patent Document 1 has the following problems. That is, in Patent Document 1, both the interchangeable lens side and the camera side have shake detection means, but when the focal plane shutter in the camera is driven during shooting, the signal obtained by the shake detection means on the camera side is It is thought that noise associated with shutter driving is mixed in. If noise is mixed into the signal from the shake detection means, the accuracy of shake correction will decrease.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to highly accurately correct shake in an imaging system consisting of an interchangeable lens and a camera body.

In order to achieve the above object, the image stabilization system of the present invention includes a determining means for determining whether or not a predetermined motion accompanied by vibration is instructed, and an image stabilization system that performs image stabilization based on the result of the determination by the determining means. a setting means for setting a correction ratio for image stabilization performed by the apparatus and the lens unit; and a setting means for generating a first image stabilization signal based on the image stabilization signal detected in the imaging device and the correction percentage in the imaging device. 1 generation means, and a first control means for controlling the first shake correction means in the imaging device based on the first shake correction signal, the first shake correction means: The setting means includes an image sensor and a moving means for moving the image sensor on a plane on which the image sensor is installed, and when the judgment means determines that the predetermined operation is instructed, the setting means: A first period during which vibrations due to the predetermined action continue after it is determined that the predetermined action has been instructed, and before it is determined that the predetermined action has been instructed. The correction rate in the imaging device is switched to a second correction rate that is lower than the first correction rate in the device.

According to the present invention, it is possible to correct shake with high precision in an imaging system including an interchangeable lens and a camera body.

FIG. 1 is a block diagram showing the configuration of an imaging system according to a first embodiment of the present invention. FIG. 3 is a schematic diagram showing an example of a signal output from the camera side shake detection section in the first embodiment. 5 is a timing chart showing control of correction ratio in the first embodiment. 7 is a flowchart showing image blur correction processing during still image shooting in the first embodiment. 7 is a timing chart showing switching of correction ratios in a modified example. 7 is a flowchart showing image blur correction processing during still image shooting in the second embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the claimed invention. Although a plurality of features are described in the embodiments, not all of these features are essential to the invention, and the plurality of features may be arbitrarily combined. Furthermore, in the accompanying drawings, the same or similar components are designated by the same reference numerals, and redundant description will be omitted.

<First embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4.

●Configuration of Imaging System FIG. 1 is a block diagram showing the configuration of a digital single-lens camera as an example of an imaging system equipped with an image stabilization system according to this embodiment. As shown in FIG. 1, the imaging system in this embodiment mainly includes a camera body 1 and an interchangeable lens 2 (lens unit). The camera body 1 and the interchangeable lens 2 can exchange signals via a communication section 30 that is electrically connected.

The interchangeable lens 2 includes a photographing optical system 22 that allows light to pass through, a lens side shake correction mechanism 23, a lens drive section 24, a lens side shake detection section 25, and a lens system control section 20 that controls each component of the interchangeable lens 2. include.

The photographing optical system 22 includes a plurality of lenses such as a shake correction lens, a focus lens, and a zoom lens, an aperture, and the like. The lens system control section 20 receives a command signal from the camera system control section 10, which will be described later, and sends a control signal to the lens drive section 24 for controlling the focus lens, zoom lens, aperture, etc. included in the photographic optical system 22. send. The lens driving section 24 adjusts the optical system by driving the focus lens, zoom lens, aperture, etc. based on this control signal.

The lens side shake detection section 25 is composed of a gyro sensor, detects angular shake in the interchangeable lens 2, and sends the detected shake signal to the lens side shake correction control section 26 included in the lens system control section 20. The lens side shake correction control section 26 performs filter processing, integration processing, etc. on the shake signal from the lens side shake detection section 25 to calculate the amount of shake. Then, a shake correction signal, which is a drive signal for the shake correction lens included in the photographing optical system 22, is generated based on the calculated shake amount and a correction rate from a correction rate control unit 34, which will be described later. The lens side shake correction mechanism 23 corrects shake by shifting the shake correction lens in a direction substantially orthogonal to the optical axis 21 of the photographing optical system 22 in response to a shake correction signal from the lens side shake correction control unit 26. Correct.

In the camera body 1, the focal plane shutter 14 (hereinafter referred to as "shutter 14") has a shutter curtain consisting of a front curtain and a rear curtain, and each shutter curtain is made to run within a shutter opening. Thereby, blocking and passing of the light beam that has passed through the photographing optical system 22 of the interchangeable lens 2 to the image sensor 11 is controlled. The drive of the shutter 14 is controlled by a shutter drive control section 35 within the camera system control section 10.

The image sensor 11 is composed of a CMOS sensor, a CCD, or the like, and receives the light beam that has passed through the photographing optical system 22 of the interchangeable lens 2 and the aperture of the shutter 14, and photoelectrically converts it into an analog electrical signal. The converted analog electrical signal is quantized by an A/D converter (not shown), converted into a digital signal (image data), and sent to the image processing section 12. The image processing unit 12 includes a white balance circuit, a gamma correction circuit, an interpolation calculation circuit, etc. therein, and generates image data from the signal acquired from the image sensor 11 in response to an instruction from the camera system control unit 10. . The image data generated by the image processing section 12 is stored in the memory 13.

The camera body 1 also includes an operation section 15 for accepting operations by a user, and an image display section 16 for displaying images and the like.

The camera system control unit 10 includes a CPU (central processing unit) and the like, and controls the camera body 1 including communication with the interchangeable lens 2 . When the release button included in the operation unit 15 is pressed and a shooting instruction is received, the camera system control unit 10 generates a timing signal etc. in accordance with the shooting instruction, controls the image sensor 11, etc., and controls the lens. A control signal is transmitted to the system control unit 20.

Further, in the camera body 1, the camera side shake detection section 31 is composed of a gyro sensor, detects angular shake in the camera body 1, and transmits the detected shake signal to the camera side shake correction control section in the camera system control section 10. Send to 32. The camera side shake correction control section 32 performs filter processing, integration processing, etc. on the signal from the camera side shake detection section 31 to calculate the amount of shake. Then, based on the calculated shake amount and the correction rate from the correction rate control unit 34 in the camera system control unit 10, a shake correction signal that is a drive signal for the image sensor 11 is generated. The camera side shake correction mechanism 33 reduces shake by shifting the image sensor 11 in a direction substantially orthogonal to the optical axis 21 of the photographing optical system 22 in response to a shake correction signal from the camera side shake detection section 31. to correct.

The correction ratio control unit 34 controls the correction ratio of the correction drive to be shared between the camera body 1 side and the interchangeable lens 2 side when the imaging system performs shake correction according to the focal length of the interchangeable lens 2, the shooting sequence, etc. decide. Then, the correction ratio determined by the correction ratio control section 34 is sent to the camera side shake correction control section 32 and the lens side shake correction control section 26, respectively.

For example, if the correction ratio is 1:1 between the camera body 1 side and the interchangeable lens 2 side, the camera side shake correction control section 32 attenuates the shake signal detected by the camera side shake detection section 31 to 50%, The correction drive amount in the camera side shake correction mechanism 33 is calculated. On the other hand, the lens side shake correction control unit 26 attenuates the shake signal detected by the lens side shake detection unit 25 to 50%, and calculates the correction drive amount of the lens side shake correction mechanism 23.

●Influence of Vibration Noise Next, using FIG. 2, the influence of vibration noise on the shake signal of the camera side shake detection unit 31 due to the drive of the shutter 14 will be explained.

FIG. 2 shows a shake signal detected by the camera side shake detection unit 31, with the horizontal axis indicating time and the vertical axis indicating the angular velocity [deg/s] which is the detection level of the shake signal. In FIG. 2, the camera side shake detection unit 31 detects rotational vibration due to camera shake of the camera body 1 in the entire time domain, but at time t11, vibration noise (shutter This indicates that noise (noise) is starting to mix in. The shutter noise gradually attenuates from time t11 to time t12.

When the camera side shake correction control unit 32 performs processing such as integration on the shake signal mixed with this shutter noise component to calculate the correction drive amount, the shake correction cannot be performed correctly and the shake correction accuracy decreases. It ends up. Since the exposure of a still image is started by the movement of the front curtain of the shutter 14, the accuracy of shake correction during still image exposure is particularly reduced. Therefore, in the present embodiment, by controlling the correction ratio, a decrease in shake correction accuracy during still image exposure due to the influence of vibrations accompanying the operation, such as shutter noise, is suppressed. Specifically, by changing the correction rate depending on whether or not an operation that is known to cause vibration (predetermined operation accompanied by vibration), such as driving the shutter 14, is being performed, Reduces the effects of vibrations associated with operations such as shutter noise.

Note that the shutter noise component is also mixed into the shake signal detected by the lens side shake detection section 25, but the shutter 14 is attached inside the camera body 1, and the vibration transmission path is higher than that of the camera side shake detection section 31. Because it is far away, the impact is small.

●Correction ratio and timing Next, using FIG. 3, the control of the correction ratio by the correction ratio control unit 34 and its timing in this embodiment will be explained.

FIG. 3 is a timing chart showing the control of the correction ratio by the correction ratio control unit 34 and the running timing of the front curtain of the shutter 14, and the horizontal axis shows time. "Lens-side correction ratio" and "camera-side correction ratio" indicate the correction ratio shared between the interchangeable lens 2 side and the camera body 1 side, respectively, and "shutter" indicates the running timing of the front curtain of the shutter 14. There is.

As shown in FIG. 3, at time t0, which is the start of the shake correction drive, the correction ratio control unit 34 sets the correction ratio to 60% on the camera body 1 side and 40% on the interchangeable lens 2 side.

At time t1, when a still image shooting instruction is issued by pressing the release button included in the operation unit 15, the correction ratio control unit 34 changes the correction ratio to 0% on the camera body 1 side and 100% on the interchangeable lens 2 side. be done.

Then, at time t2, the shutter drive control section 35 starts running the front curtain of the shutter 14, thereby starting exposure, and at time t3, the running of the front curtain ends. Time t2 corresponds to the timing of time t11 in FIG.

Next, at time t4, the correction ratio control unit 34 resets the correction ratio to 60% on the camera body 1 side and 40% on the interchangeable lens 2 side. The movement of the front curtain of the shutter 14 ends at time t3, but as shown in FIG. 2, the vibration of the shutter noise continues even after the movement of the front curtain ends, so the vibration of the shutter noise continues until the shutter noise falls to a certain level. does not change the correction ratio.

Thereafter, the rear curtain of the shutter 14 runs, exposure is completed, and still image photography is completed. Note that since still image shooting ends when the rear curtain of the shutter 14 runs, the correction ratio is not changed in this embodiment.

In this way, during the period when shutter noise is mixed in the camera side shake detection unit 31 during shooting, the correction rate control unit 34 controls the correction rate to be 0% on the camera body 1 side and 100% on the interchangeable lens 2 side. do. By performing such control, it is possible to prevent a decrease in correction accuracy by the camera side shake correction mechanism 33 due to shutter noise mixed in the shake signal of the camera side shake detection section 31.

Note that, as long as the magnitude of the shutter noise at time t4 has a small influence on the shake correction operation, the shutter noise does not need to be completely suppressed. Therefore, the signal until only the shutter noise stabilizes is measured in advance, and the time required until the amplitude of the shutter noise reaches an allowable value is determined, and the period from time t1 to time t4 may be determined.

Alternatively, instead of predetermining the length of the period from time t1 to t4, the predetermined period may be determined using the signal from the camera side shake detection section 31 as follows. First, high frequency components such as 100 Hz or more, which are different from camera shake, are extracted from the shake signal from the camera side shake detection section 31 using a BPF (band pass filter) or the like. Then, when it is determined from the extracted high-frequency component signal that the shutter noise has fallen within a desired amplitude, a command may be issued to the correction ratio control section 34 to change the correction ratio. In addition to using the shake signal from the camera side shake detection section 31, a separate acceleration sensor or the like is installed near the camera side shake detection section 31, and the timing for switching the correction ratio is determined based on the result of the acceleration sensor signal. Also good.

Note that the correction ratios on the camera body 1 side and the interchangeable lens 2 side described above are not limited to the values mentioned above, and the correction ratio on the camera body 1 side is determined by adjusting the correction ratio on the camera body 1 side while shutter noise is occurring. Control can be performed to make it smaller than when it is not occurring. At that time, it may be determined based on the amount that can be corrected by the camera side shake correction mechanism 33 and the lens side shake correction mechanism 23 and the focal length of the interchangeable lens 2.

●Image blur correction processing Next, the flow of image blur correction processing in the first embodiment will be described using FIG. 4. FIG. 4 is a flowchart of image blur correction processing during still image shooting, which is controlled by the camera system control unit 10.

When the process starts, in S101, shake correction driving is started on the camera body 1 side and the interchangeable lens 2 side based on a correction ratio predetermined by the correction ratio control unit 34. The correction ratio in S101 corresponds to the time before time t1 in FIG. 3, and is set, for example, to 60% on the camera body 1 side and 40% on the interchangeable lens 2 side.

In S102, it is determined whether the release button included in the operation unit 15 has been pressed and an instruction to shoot a still image has been issued. The process waits by repeating S102 until it is determined that a photographing instruction has been given. If it is determined that a photographing instruction has been given, the process advances to S103.

In S103, the correction ratio control unit 34 changes the correction ratio set in S101 to 0% on the camera body 1 side and 100% on the interchangeable lens 2 side. S103 corresponds to time t1 in FIG.

In S104, the shutter drive control unit 35 causes the front curtain of the shutter 14 to start moving, thereby starting still image photography exposure. S104 corresponds to time t2 in FIG.

In S105, it is determined whether a predetermined change condition such as the elapse of a predetermined period after changing the correction ratio in S103 is satisfied, and the process waits until the change condition is satisfied, and the process waits until the change condition is satisfied. If it is determined that this is the case, the process advances to S106.

In S106, the correction ratio control unit 34 changes the correction ratio to the original ratio. S106 corresponds to time t4 in FIG.

In S107, the shutter drive control unit 35 drives the shutter 14, and the trailing curtain starts running. This completes the still image shooting exposure.

In S108, the process returns to S102 and repeats the process until the camera body 1 is powered off. When it is determined that the power of the camera body 1 has been turned off, the process ends.

As described above, according to the first embodiment, the camera body 1 side and the interchangeable lens 2 side share the shake correction based on the correction ratio determined by the correction ratio control unit 34, so that the entire imaging system The amount of shake correction can be increased. Further, while shutter noise is occurring, by lowering the correction ratio of the shake correction amount on the camera body 1 side, which is more affected by shutter noise, it is possible to correct shake with high precision.

In addition, since the correction ratio control unit 34 only sends correction ratio information to the camera side shake correction control unit 32 and the lens side shake correction control unit 26, compared to sending a shake signal, a shake correction signal, etc. , the communication load can be reduced.

For example, when transmitting a signal from the camera side shake detection section 31 to the lens side shake correction control section 26 via the communication section 30 and calculating the correction driving amount of the lens side shake correction mechanism 23 using the result, the shake correction Since the sampling rate of the shake signal required for control is high, high-speed communication via the communication section 30 is required. Further, it is conceivable that the calculation processing load increases due to the influence of communication delay and the communication processing of the camera system control section 10 and the lens system control section 20.

On the other hand, in the present embodiment, it is only necessary to communicate information on the correction ratio only at the timing of changing the correction ratio, so high-speed communication is not required and the computational processing load associated with communication can be kept low.

<Modified example>
In the first embodiment described above, the correction ratio is changed discontinuously by the correction ratio control unit 34, but the correction ratio may be controlled as follows. FIG. 5 is a timing chart showing the correction ratio by the correction ratio control unit 34 and the shutter travel timing in the modified example. Similar to FIG. 3, the horizontal axis shows time, and the vertical axis shows the shared correction ratio and drive timing of the front curtain of the shutter 14.

The operation from time t20 to time t23 is the same as the operation from time t0 to time t3 in FIG. 3, so a description thereof will be omitted.

At time t24, the correction ratio control unit 34 changes the correction ratio, but gradually changes the correction ratio on the interchangeable lens 2 side from time t24 to time t25 so that it approaches asymptotically from 100% to 40%. Similarly, the correction ratio on the camera body 1 side is gradually changed from time t24 to time t25 so that the correction ratio approaches asymptotically from 0% to 60%. Note that control is performed so that the sum of the correction ratios on the interchangeable lens 2 side and on the camera body 1 side at each time becomes 100%.

At time t25, the correction ratio returns to the one before the change, and thereafter, shake correction is performed at the fixed correction ratio until the end of shooting.

By controlling the correction ratio in this way, the change in the correction ratio for shake correction becomes smoother, so compared to changing the correction ratio on the camera body 1 side from 0% to 60% all at once, it is easier to start driving. The movement becomes smoother. Note that when changing the correction ratio at time t21, the correction ratio may be similarly changed so as to approach the changed correction ratio, but if the period from time t21 to time t22 is set appropriately, Since the unstable operation of the shake correction operation caused by discontinuous changes in the shake correction ratio is stabilized, there is little influence on the shake correction accuracy. Specifically, when the correction ratio on the camera body 1 side is changed from 60% to 0% at time t21, the shake correction amount drive amount becomes discontinuous, and the operation wave of the camera side shake correction mechanism 33 becomes like a step response. This may result in so-called overshoot, which may result in unstable operation. In that case, it takes a certain amount of time until the so-called overshoot subsides and the blur correction operation stabilizes.

On the other hand, when overshoot is reduced by PID control, it takes a certain amount of time for the operation of the camera side shake correction mechanism 33 to eliminate the delay with respect to the shake correction driving amount and to follow the movement as desired. However, if the period from time t21 to time t22 is set appropriately, the shake correction operation will be stabilized by time t22, so there will be little effect on shake correction accuracy. Therefore, when changing the correction ratio after at least the period related to the driving of the shutter 14 ends, it is desirable that the correction ratio asymptotically approximates the value of the period other than the period related to the driving of the shutter 14 as described above.

Further, as described above, the correction ratio control unit 34 determines the correction ratio for periods other than the period in which shutter noise is mixed, based on the focal length of the interchangeable lens 2 and the like. For example, when the same amount of shake occurs, if the focal length is short, the amount of shake on the image plane of the image sensor 11 will be smaller, so the camera side shake correction mechanism 33 will need more image capture to perform shake correction. The amount of movement of the element 11 is smaller than when the focal length is long. Therefore, the correction ratio on the camera body 1 side is set to increase as the focal length becomes shorter.

On the other hand, as the focal length becomes longer, the amount of shake on the image plane of the image sensor 11 increases, and the drive capacity of the camera side shake correction mechanism 33 becomes insufficient, so the correction ratio on the side of the interchangeable lens 2 is set to be increased. Ru. For example, assume that the interchangeable lens 2 with a long focal length is attached and the correction ratio is set to 10% on the camera body 1 side and 90% on the interchangeable lens 2 side. In this case, even if a signal mixed with shutter noise from the camera side shake detection section 31 is used, the correction ratio on the camera body 1 side is small, so the influence on the shake correction accuracy is small. Therefore, when the focal length is longer than a predetermined distance, the correction ratio control unit 34 may not switch the correction ratio during the predetermined period required for the front curtain of the shutter 14 to travel.

Furthermore, if the still image exposure time is very short, the still image exposure may end before the shutter noise subsides to a desired level. Furthermore, if the still image exposure time is short, the amount of shake during the exposure period will be small, so it is conceivable that it can be compensated for only by the amount of correction drive of the lens side shake correction mechanism 23. Therefore, if the photographing exposure time predetermined before photographing is shorter than the predetermined time, the correction ratio control unit 34 may not switch the correction ratio during the predetermined period related to the operation of the shutter 14. For example, when the still image exposure time is 1/100 seconds, the correction ratio on the interchangeable lens 2 side before starting still image exposure is set to 100%, and the correction ratio controller also controls the predetermined period for the front curtain of the shutter 14 to travel. 34 may not be performed.

Further, in the above embodiment, the camera side shake correction mechanism 33 is changed to 0% during a predetermined period related to the movement of the front curtain of the shutter 14, but it is limited to 0% if the effect of shutter noise is reduced. isn't it. At least, it is desirable that the correction ratio on the side of the interchangeable lens 2 is larger during other periods than during the predetermined period related to the running of the front curtain of the shutter 14.

In addition, the correction ratio is determined before still image exposure (time t0 to t1 in FIG. 3, time t20 to t21 in FIG. 5) and after the end of a predetermined period (after time t4 in FIG. 3, after time t25 in FIG. 5). do not have to be the same. For example, the correction ratio on the camera body 1 side may be set to 100% before still image exposure, and the correction ratio on the camera body 1 side may be set to 60% after the end of a predetermined period.

Furthermore, the amount of correction may be limited before still image exposure. For example, before still image exposure, driving may be performed with the correction amount limited to less than 100% (for example, 1/2) of the amount of shake determined from the signal from the shake detection section. This is because shake correction is performed before still image exposure, so if still image exposure is started with the shake correction mechanism at the edge of its movable range, the shake correction mechanism will be able to correct the shake during still image exposure. This is because the amount of correction may become smaller. Therefore, before still image exposure, the original correction ratios are each halved and the correction ratios are sent to the camera side shake correction control section 32 and the lens side shake correction control section 26. For example, if the original correction ratio is 60% on the camera body 1 side and 40% on the interchangeable lens 2 side, the correction ratio may be controlled as 30% on the camera body 1 side and 20% on the interchangeable lens 2 side.

Furthermore, in the above embodiment, the period in which the correction rate is reduced on the camera body 1 side is set as the period related to the running of the front curtain of the shutter 14, but the period related to the running of the trailing curtain of the shutter 14 and the shutter charging operation of the shutter 14 is also taken. This is the period during which the shutter, which is a driving mechanism, is operating. Therefore, the period related to the running of the rear curtain of the shutter 14 and the shutter charging operation of the shutter 14 may be similarly controlled by switching the correction ratio. For example, noise is mixed into the camera side shake detection unit 31 due to the running of the rear curtain of the shutter 14 and the shutter charging operation. As a result, the image displayed on the image display unit 16 immediately after still image shooting (so-called live view image) displays a low-quality shake-corrected image affected by noise. Further, when the imaging system is a single-lens reflex camera having a mirror, the mirror drive mechanism is also the photographing drive mechanism. Therefore, the operation of the photographing drive mechanism may be the mirror-up operation (retreating the mirror from the optical path) of the mirror drive mechanism. In this way, the correction rate on the camera body 1 side may be lowered when a predetermined operation accompanied by vibration as described above is instructed other than the movement of the front curtain shutter.

It is also conceivable that an interchangeable lens not equipped with a shake correction mechanism may be attached to the camera body 1. In that case, the communication unit 30 determines whether the interchangeable lens 2 to which the camera system control unit 10 is attached is equipped with a shake correction mechanism. If a shake correction mechanism is not installed, the correction ratio control unit 34 may control the correction ratio on the camera side to always be 100% during the period related to the operation of the shutter 14 and other periods as well.

<Second embodiment>
Next, a second embodiment of the present invention will be described. Note that the configuration of the imaging system in the second embodiment is the same as that described in the first embodiment with reference to FIG. 1, so a description thereof will be omitted. However, the imaging system of the second embodiment is capable of high-speed communication via the communication unit 30.

●Image blur correction processing Next, processing in the second embodiment will be explained using FIG. 6. FIG. 6 is a flowchart of image blur correction processing during still image shooting. In the second embodiment, except for the predetermined period related to the operation of the shutter 14, the shake correction drive of the lens side shake correction mechanism 23 and the camera side shake correction mechanism 33 is performed using the shake signal detected by the camera side shake detection unit 31. Calculate the amount.

When the process starts, in S201, a shake signal detected by the camera side shake detection section 31 is sent to the camera system control section 10. Then, the sent shake signals are divided based on a predetermined ratio by the correction ratio control section 34 and sent to the camera side shake correction control section 32 and the lens side shake correction control section 26 via the communication section 30, respectively. sent to. For example, the shake signal detected by the camera side shake detection unit 31 is sent to the camera side shake correction mechanism 33 at a rate of 60%, and to the lens side shake correction mechanism 23 at a rate of 40%. Then, the camera side shake correction control section 32 and the lens side shake correction control section 26 perform filter processing, integration processing, etc. on the shake signals sent at a predetermined rate, and calculate the amount of shake. Then, from the calculated shake amount, shake correction signals for the camera side shake correction mechanism 33 and the lens side shake correction mechanism 23 are generated, and shake correction is performed. At this time, the lens side shake detection section 25 is controlled not to operate, or is controlled not to use the shake signal detected by the lens side shake detection section 25.

In S202, it is determined whether the release button included in the operation unit 15 has been pressed and an instruction to shoot a still image has been issued. The process repeats S202 and waits until it is determined that a photographing instruction has been given. If it is determined that a photographing instruction has been given, the process advances to S203.

In S203, the correction ratio control unit 34 changes the correction ratio set in S201 to 0% on the camera body 1 side and 100% on the interchangeable lens 2 side. At the same time, the camera system control unit 10 instructs the lens side shake correction control unit 26 to generate a shake correction signal for the lens side shake correction mechanism 23 using the shake signal detected by the lens side shake detection unit 25. send.

In S204, the camera side shake correction control unit 32 stops driving the camera side shake correction mechanism 33 according to the correction ratio changed in S203. Stopping the drive of the camera side shake correction mechanism 33 means stopping and holding the movement of the image sensor 11 at that position. On the other hand, the lens side shake correction control section 26 performs filter processing, integration processing, etc. on the shake signal detected by the lens side shake detection section 25 to generate a shake correction signal. As a result, shake correction is performed only by driving the lens side shake correction mechanism 23.

In S205, the shutter drive control unit 35 causes the front curtain of the shutter 14 to start moving, thereby starting still image shooting exposure.

In S206, it is determined whether a predetermined change condition such as the elapse of a predetermined period after changing the correction ratio in S204 is satisfied, and the process waits until the change condition is satisfied, and the process waits until the change condition is satisfied. If it is determined that this is the case, the process advances to S207.

In S207, the correction ratio control unit 34 changes the correction ratio to the original ratio. Then, the camera system control unit 10 sends a command to the lens side shake correction control unit 26 to generate a shake correction signal for the lens side shake correction mechanism 23 using the shake signal detected by the camera side shake detection unit 31. .

In S208, a signal indicating the detection result of the camera side shake detection section 31 is sent to the camera system control section 10. The sent signals are then transmitted to the lens side shake correction control unit 26 via the camera side shake correction control unit 32 and the communication unit 30, respectively, based on the ratio determined in S207. Then, the camera side shake correction control unit 32 and the lens side shake correction control unit 26 each perform filter processing, integration processing, etc. on the signals sent at a predetermined rate, and the camera side shake correction mechanism 33 and the lens side shake correction A shake correction signal for the side shake correction mechanism 23 is generated to perform shake correction.

In S209, the shutter 14 is driven by the shutter drive control unit 35, and the trailing curtain starts running. This completes the still image shooting exposure.

In S210, the process returns to S201 and is repeated until the camera body 1 is powered off. When it is determined that the power of the camera body 1 has been turned off, the process ends.

As described above, according to the second embodiment, the shake correction is performed based on the shake signal detected by the lens side shake detection unit 25 during a predetermined period from immediately before the front curtain travels, which is a period related to the drive of the shutter 14. . Thereby, it is possible to prevent a decrease in the accuracy of shake correction due to shutter noise mixed into the camera side shake detection section 31, so that shake can be corrected with high accuracy.

Furthermore, in the second embodiment, high-speed communication via the communication unit 30 is possible, so a shake signal with a high sampling rate can be transmitted. If such high-speed communication is possible, if the performance of the lens side shake detection section 25 of the attached interchangeable lens 2 is lower than the performance of the camera side shake detection section 31, it will be detected by the camera side shake detection section 31. Using the shake signal, shake correction can be performed using shake correction mechanisms on both the camera side and the lens side. On the other hand, by using the signal from the lens side shake detection section 25 only during a predetermined period related to the operation of the shutter 14, the influence of shutter noise can be reduced, and highly accurate shake correction can be performed.

Note that before the signal from the camera side shake detection section 31 is transmitted to the lens side shake correction control section 26 via the communication section 30, the signal may be down-sampled in accordance with the communication rate at the communication section 30. For example, if the signal from the camera side shake detection unit 31 before downsampling is 20kHz, the signal is changed to 500Hz or the same as the communication rate by downsampling.

In addition, in the second embodiment, except for a predetermined period related to the operation of the shutter 14, the communication unit transmits the result of multiplying the shake signal detected by the camera side shake detection unit 31 by the correction rate determined by the correction rate control unit 34. 30 to the lens side shake correction control unit 26. However, the present invention is not limited to this, and may be controlled as follows. For example, based on the result of the camera side shake detection unit 31 and the correction rate set by the correction rate control unit 34, the camera side shake correction control unit 32 generates a shake correction signal for the camera side shake correction mechanism 33, and also generates a shake correction signal for the camera side shake correction mechanism 33. A shake correction signal for the shake correction mechanism 23 is also generated. Then, the shake correction signal of the lens side shake correction mechanism 23 generated by the camera side shake correction control section 32 is transmitted to the lens side shake correction control section 26 via the communication section 30 .

<Other embodiments>
Note that even if the present invention is applied to a system composed of a plurality of devices (for example, a host computer, an interface device, a scanner, a video camera, etc.), it can be applied to a system composed of a single device (for example, a copying machine, a facsimile machine, etc.). May be applied to

Further, the present invention provides a system or device with a program that implements one or more functions of the above-described embodiments via a network or a storage medium, and one or more processors in a computer of the system or device executes the program. This can also be realized by reading and executing processing. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

The invention is not limited to the embodiments described above, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the following claims are hereby appended to disclose the scope of the invention.

1: Camera body, 2: Interchangeable lens, 10: Camera system control section, 11: Image sensor, 12: Image processing section, 14: Focal plane shutter, 15: Operation section, 20: Lens system control section, 22: Photographing optics System, 23: Lens side shake correction mechanism, 24: Lens drive section, 25: Lens side shake detection section, 30: Communication section, 31: Camera side shake detection section, 32: Camera side shake correction control section, 33: Camera side Shake correction mechanism, 34: Correction ratio control section, 35: Shutter drive control section

Claims (23)

Judgment means for determining whether a predetermined action involving vibration has been instructed;
a setting means for setting a correction ratio of shake correction performed by the imaging device and the lens unit based on the result of the judgment by the judgment means;
a first generation unit that generates a first shake correction signal based on a shake signal detected in the image pickup device and a correction ratio in the image pickup device;
a first control means for controlling a first shake correction means in the imaging device based on the first shake correction signal;
The first shake correction means includes an image sensor and a moving means for moving the image sensor in a plane on which the image sensor is installed,
When the determining means determines that the predetermined action has been instructed, the setting means may cause the vibration caused by the predetermined action to continue after it is determined that the predetermined action has been instructed. During the first period during which the predetermined operation is performed, the correction rate in the imaging device is set to a second correction rate that is lower than the first correction rate in the imaging device before it is determined that the predetermined operation is instructed. An image stabilization system characterized by switching. When it is determined by the determining means that the predetermined operation is instructed, the setting means further determines the correction rate in the lens unit during the first period so that the predetermined operation instructs the correction ratio in the lens unit. 2. The image stabilization system according to claim 1, wherein the image stabilization system switches to a fourth correction ratio higher than the third correction ratio in the lens unit before it is determined that the image stabilization ratio has been changed. a second generation means for generating a second shake correction signal based on the shake signal detected in the lens unit and a correction ratio in the lens unit;
a second control means for controlling a second shake correction means in the lens unit based on the second shake correction signal;
The image stabilization system according to claim 1 or 2 , further comprising: The setting means is characterized in that after the first period has elapsed, the second correction rate in the imaging device is gradually changed to a 53rd correction rate that is larger than the second correction rate. The image stabilization system according to any one of claims 1 to 3 . If the determining means does not determine that the predetermined action has been instructed,
The first generating means further generates a shake signal to be transmitted to the lens unit based on the shake signal detected in the imaging device and a correction ratio in the lens unit,
The second generation means generates a second shake correction signal based on the transmitted shake signal,
when the determining means determines that the predetermined action is instructed, the first period;
The setting means sets a correction ratio in the imaging device to 0% and sets a correction ratio in the lens unit to 100%,
4. The second generating means generates a second shake correction signal based on a shake signal detected in the lens unit and a correction ratio in the lens unit. Image stabilization system. The image stabilization system according to any one of claims 1 to 5 , wherein the sum of the correction ratio in the imaging device and the correction ratio in the lens unit is 100%. The predetermined operation is still image shooting, and before still image shooting is instructed, the setting means sets the total of the correction ratio in the imaging device and the correction ratio in the lens unit to less than 100%. The image stabilization system according to any one of claims 1 to 5 , wherein the image stabilization system is limited to . Image shake according to any one of claims 1 to 7 , wherein the predetermined operation is an operation including at least one of driving a shutter, charging a shutter, and retracting a mirror from an optical path. correction system. The image forming apparatus according to claim 3 , wherein the setting means sets the first correction ratio based on a correction amount that can be corrected by the first shake correction means and the second shake correction means. Shake correction system. The image blur correction according to any one of claims 1 to 9 , wherein the setting means sets the first correction ratio to increase as the focal length of the lens unit becomes shorter. system. The image shake according to any one of claims 1 to 10 , wherein the setting means sets the correction ratio in the lens unit to increase as the focal length of the lens unit becomes longer. correction system. 2. The setting means does not switch from the first correction ratio to the second correction ratio when the focal length of the lens unit is longer than a predetermined focal length. 12. The image stabilization system described in 11 . The setting means does not switch from the first correction rate to the second correction rate when an instruction is given to shoot a still image with an exposure time shorter than a predetermined exposure time. The image stabilization system according to any one of claims 1 to 12 . The image stabilization system according to any one of claims 1 to 13 , wherein the first period is a time period until vibrations associated with the predetermined operation stabilize. further comprising extraction means for extracting a high frequency component of the shake signal,
3. The first period is a time period from when it is determined that the predetermined operation is instructed until the amplitude of the high frequency component signal falls within a predetermined amplitude. 14. The image stabilization system according to any one of Items 1 to 13 . 14. The first period is set based on a signal from an acceleration sensor provided in the imaging device after it is determined that the predetermined action is instructed . The image stabilization system according to any one of the items. When the lens unit is not equipped with a shake correction means, the setting means sets the correction ratio in the imaging device to 100% regardless of the result of the judgment by the judgment means. The image stabilization system according to item 1. An imaging device equipped with the image stabilization system according to claim 1 or 17 . An imaging system comprising the imaging device and the lens unit, comprising the image stabilization system according to any one of claims 1 to 17 . a determination step in which the determination means determines whether a predetermined action involving vibration is instructed;
a setting step in which the setting means sets a correction ratio of shake correction to be performed by the imaging device and the lens unit based on the result of the judgment by the judgment means;
a first generation step in which a first generation means generates a first shake correction signal based on a shake signal detected in the image pickup device and a correction ratio in the image pickup device;
a first control step in which the first control means controls the first shake correction means in the imaging device based on the first shake correction signal;
The first shake correction means includes an image sensor and a moving means for moving the image sensor in a plane on which the image sensor is installed,
When it is determined in the determination step that the predetermined motion has been instructed, in the setting step, the vibration due to the predetermined motion continues after it is determined that the predetermined motion has been instructed. During the first period during which the predetermined operation is performed, the correction rate in the imaging device is set to a second correction rate that is lower than the first correction rate in the imaging device before it is determined that the predetermined operation is instructed. An image stabilization method characterized by switching. a second generation step in which a second generation means generates a second shake correction signal based on the shake signal detected in the lens unit and the correction ratio in the lens unit;
a second control step in which a second control means controls a second shake correction means in the lens unit based on the second shake correction signal;
21. The image blur correction method according to claim 20 , further comprising: A program for causing a computer to function as each means of the image blur correction system according to any one of claims 1 to 17 . A computer readable storage medium storing the program according to claim 22 .

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