JP2024071858A - Image stabilizer, image stabilizer method, and image capture device - Google Patents

Abstract

To control shake correction by reducing the influence of vibration generated by a movement of a shake correction mechanism.SOLUTION: A shake correction control device comprises: acquisition means that acquires an imaging apparatus shake detection signal from shake detection means; and shake correction control means that acquires a drive command signal for shake correction means based on the shake detection signal acquired from the shake detection means, and outputs a driving signal to the shake correction means to control shake correction. The shake correction control means acquires the current drive command signal based on the shake detection signal and the previous drive command signal.SELECTED DRAWING: Figure 2

Description

The present invention relates to a blur correction device and method for correcting blur during shooting, and an imaging device.

In recent years, as imaging devices have become more powerful, many imaging devices and photographing lenses are equipped with image stabilization mechanisms. The image stabilization mechanism allows users to reduce the effect of blur on the captured image when taking pictures using an imaging device. Several types of image stabilization mechanisms have been proposed for use in imaging devices, including a method that performs image stabilization by driving a part of the lens in the photographing optical system, and a method that performs image stabilization by driving the image sensor. In lens-interchangeable imaging devices, the former is a method in which image stabilization is performed by driving a part of the lens in the photographing optical system inside an interchangeable lens barrel, and the latter is a method in which image sensor in the camera body is driven to perform image stabilization. A combination of the two is also known, where image stabilization is performed by driving both a part of the lens in the photographing optical system and the image sensor.

In imaging devices that use such image stabilization mechanisms, there is a problem in that vibrations generated by the operation of drive units within the imaging device, such as the shutter, are transmitted to the shake detection means provided to detect camera shake, causing the image stabilization mechanism to operate regardless of camera shake.

To address this issue, a technique is known that changes the signal processing of the shake detection means while the drive unit in the imaging device is operating, thereby reducing the effects of vibration.

JP 2011-59429 A

However, Patent Document 1 does not mention that vibrations generated by the movement of the image stabilization mechanism may affect the image stabilization means.

The present invention was made in consideration of the above problems, and aims to control blur correction by reducing the effects of vibrations caused by movement of the blur correction mechanism.

A blur correction control device according to one aspect of the present invention includes an acquisition means for acquiring a blur detection signal of an imaging device from a blur detection means, and a blur correction control means for acquiring a drive command signal for the blur correction means based on the blur detection signal acquired from the blur detection means and controlling blur correction by outputting a drive signal to the blur correction means, the blur correction control means acquiring a current drive command signal based on the blur detection signal and the previous drive command signal. Other aspects of the present invention will be made clear in the embodiments described below.

The image stabilization can be controlled by reducing the effects of vibrations caused by the movement of the image stabilization mechanism.

1 is a schematic diagram and a block diagram of an imaging device according to a first embodiment of the present invention; Block diagram of a shake correction system in the first embodiment FIG. 4 is a diagram for explaining a shake detection and correction signal in the first embodiment. Control flow chart in the first embodiment Schematic diagram and block diagram of an imaging device according to a second embodiment Block diagram of a shake correction system in the second embodiment 1 is a schematic diagram and a block diagram of an imaging device according to a third embodiment of the present invention; Block diagram of a shake correction system in the third embodiment.

The following embodiments are described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe multiple features, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicate explanations are omitted.

The imaging device according to the first embodiment of the present invention will be described below with reference to Figs. 1 to 4. Fig. 1(a) is a schematic diagram of the imaging system according to the present embodiment, and Fig. 1(b) is a block diagram showing the electrical configuration of the imaging system.

Figure 1(a) shows an imaging system consisting of a camera body 1 and a lens barrel 2 fixed to a tripod.

When the lens barrel 2 is attached to the camera body 1, the camera body 1 and the lens barrel (interchangeable lens) 2 are electrically connected via electrical contacts 11 on the camera body 1 and the lens barrel 2. Note that in this embodiment, a so-called interchangeable lens camera in which the lens barrel 2 is detachable from the camera body 1 is described, but the present invention is not limited to this and can also be applied to a lens-integrated imaging device in which the lens barrel 2 is fixed to the camera body 1.

The configuration of the camera body 1 will be described. The camera body 1 includes a camera system control unit 5, an image sensor 6, an image processing unit 7, a memory unit 8, a display unit 9, an operation detection unit 10, electrical contacts 11, a camera-side shake correction unit 14, a camera-side shake detection unit 15, and a shutter 17.

The camera system control unit 5 includes a CPU (Central Processing Unit) and an arithmetic circuit, and controls the entire imaging system. In addition, when the lens device 2 is attached to the camera body 1 and connected, the camera system control unit 5 can communicate with the lens system control unit 12 provided in the lens device 2 via electrical contacts 11 that communicate between the camera body 1 and the lens device 2. In addition, the camera system control unit 5 generates and outputs timing signals for imaging in response to external operations, and controls the imaging system, image processing system, and recording/playback system. For example, the operation detection unit 10 detects the pressing of a shutter release button (not shown), and the camera system control unit 5 controls the drive of the imaging element 6, the operation of the image processing unit 7, compression processing, etc.

The image sensor 6 is, for example, a CCD or CMOS sensor, and photoelectrically converts the light beam from the subject that passes through the imaging optical system 3 of the lens device 2 into an electrical signal. The image sensor 6 is also provided so as to be drivable (displaceable) in a plane perpendicular to the optical axis 4 of the photographing optical system 3.

The image processing unit 7 acquires the image signal output from the image sensor 6 and performs image processing. 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, etc. inside, and can perform predetermined pixel interpolation processing and color conversion processing to generate image data for recording and image data for display. The color interpolation processing circuit performs color interpolation (demosaic) processing from the Bayer array signal to generate a color image. The image processing unit 7 also compresses images, videos, audio, etc. using a predetermined method. Furthermore, the image processing unit 7 can also generate a shake detection signal based on a comparison between multiple images obtained from the image sensor, so the image sensor 6 and the image processing unit 7 may form a camera-side shake detection unit 12.

Recording and playback are performed using a memory unit 8 and a display unit 9. The memory unit 8 has a storage unit, and the display unit 9 includes a rear display device, a small display panel (not shown) that displays shooting information provided on the top surface of the camera body 1, and an electronic viewfinder (not shown) also called an EVF. The camera system control unit 5 outputs to the recording unit of the memory unit 8, and displays an image to be presented to the user on the display unit 9. The camera system control unit 5 also controls the state of each segment of the information display device that displays information using the display unit 9. The rear display device included in the display unit 9 may be a touch panel, and configured to serve both as the display unit 9 and the operation unit.

The operation detection unit 10 detects signals from operation switches such as a shutter release button (not shown) and various other operating members, and outputs detection signals to the camera system control unit 5.

The shutter 17 is provided in front of the image sensor 6 and is opened and closed under control of the camera system control unit 5 to capture an image.

The camera-side shake correction unit 14 generates a drive command signal for the image sensor 6 based on the shake target signal from the camera system control unit 5, and drives (displaces) the image sensor 6 in a plane perpendicular to the optical axis 4. The camera-side shake correction unit 14 controls an actuator such as a voice coil motor or ultrasonic motor (not shown) using the drive command signal, thereby performing shake correction using the image sensor 6.

Camera-side shake detection unit 15 can detect rotational shake relative to optical axis 4 that is applied to the imaging system, and can be realized, for example, by using an angular velocity sensor. Camera-side shake detection unit 15 can also detect translational shake that is applied to the imaging system, and can be realized, for example, by using an acceleration sensor. Therefore, camera-side shake correction unit 14 performs shake correction by driving image sensor 6 in a plane perpendicular to optical axis 4, based on the rotational shake and translational shake detected by camera-side shake detection unit 15. The shake detection signal detected by camera-side shake detection unit 15 is output to camera system control unit 5.

The configuration of the lens device 2 will be described. The lens device 2 includes an imaging optical system 3 having multiple lenses, a lens system control unit 12, a lens side shake detection unit 16 that detects the amount of shake in the imaging system, and a lens side shake correction unit 13 that corrects image shake by driving a shake correction lens 3a in a plane perpendicular to the optical axis 4. Note that in addition to the shake correction lens 3a, the lens system control unit 12 can also drive a focus lens and an aperture (not shown) using a drive unit (not shown).

The lens system control unit 12 includes a CPU, an arithmetic circuit, etc., and controls each component of the lens device 2.

The lens side image blur correction unit 13 performs image blur correction by driving (displacing) the image blur correction lens 3a in a plane perpendicular to the optical axis 4 according to a control signal from the lens system control unit 12. The lens side image blur correction unit 13 includes an actuator such as a voice coil motor or an ultrasonic motor, and image blur correction is performed by driving and controlling this actuator by the lens system control unit 12.

The lens-side shake detection unit 16 can detect rotational shake relative to the optical axis 4 applied to the imaging system, and can be realized, for example, by using an angular velocity sensor. The shake detection signal detected by the lens-side shake detection unit 16 is output to the lens system control unit 12.

In this embodiment, the camera body 1 and the lens device 2 each have an image blur correction means. That is, the camera side shake correction unit 14 constitutes the first image blur correction means, and the lens side shake correction unit 13a constitutes the second image blur correction means. In addition, the camera side shake detection unit 15 constitutes the first shake detection unit, and the lens side shake detection unit 16 constitutes the second shake detection unit.

Note that, although this embodiment describes an imaging system having two shake correction units, lens side shake correction unit 13 and camera side shake correction unit 14, the present invention is not limited to this. The present invention is also effective for imaging systems having only one of lens side shake correction unit 13 or camera side shake correction unit 14.

In the imaging system having the above configuration, the imaging means includes an imaging optical system 3 and an imaging element 6, and an image is formed near the imaging surface of the imaging element 6 via the photographing optical system 3. Since the evaluation amount for focus state detection and the photometric amount are obtained from the output of the imaging element 6, it is possible to adjust the focus of the imaging optical system 3 and control the exposure of the imaging element 6.

The imaging system is controlled mainly by the camera system control unit 5, the operation detection unit 10, and the lens system control unit 12. The camera system control unit 5 generates timing signals for imaging and outputs them to each unit, thereby controlling the imaging system, image processing system, and recording/playback system in response to the operation signals. This makes it possible to take still images and videos. For example, when the operation detection unit 10 detects the pressing of the shutter release button, the camera system control unit 5 controls the drive of the imaging element 6, the operation of the image processing unit 7, compression processing, etc., and controls the information display by the display unit 9. When the display unit 9 is equipped with a touch panel, the camera system control unit 5 executes various processes according to operations on the display screen.

The adjustment operation of the optical system by the control system will be described. The camera system control unit 5 is connected to the image processing unit 7, which determines the appropriate focus position (position of the focus lens) and aperture position (aperture amount) based on a signal from the image sensor 6. The camera system control unit 5 then notifies the lens system control unit 12 of information indicating the appropriate focus position and aperture position via the electrical contacts 11. The lens system control unit 12 appropriately controls the focus lens driving unit and aperture driving unit (not shown) based on the notification received via the electrical contacts 11. This allows the image sensor to be exposed to an appropriate amount of subject light and the subject image to be formed near the image sensor 6.

Furthermore, in the shake correction mode, the camera system control unit 5 appropriately controls the camera side shake correction unit 14 based on the shake detection signal detected by the camera side shake detection unit 15. Similarly, the lens system control unit 12 appropriately controls the lens shake correction unit 13 based on the shake detection signal detected by the lens side shake detection unit 16. As a basic control operation of the shake correction control means, the camera system control unit 5 and the lens system control unit 12 first acquire the shake detection signals (rotational shake and translational shake) detected by the camera side shake detection unit 15 and the lens side shake detection unit 16, respectively. Based on the acquired shake detection signals, the camera system control unit 5 and the lens system control unit 12 each calculate the drive amount of the image sensor 6 and the shake correction lens 3a to correct the image shake. After that, the calculated drive amount is sent to the camera side shake correction unit 14 and the lens side shake correction unit 13 as a command value, thereby performing shake correction control using the image sensor 6 and the shake correction lens 3a.

Next, using FIG. 2, we will explain the shake correction using the camera system control unit 5 and the camera side shake correction unit 14 in this embodiment. Note that while the camera side shake correction is explained here, it can also be applied to shake correction using the lens system control unit 12 and the lens side shake correction unit 16. FIG. 2 is a control block diagram of the shake correction system provided in the camera body 1.

In FIG. 2, the camera system control unit 5 acquires the shake detection signal output from the camera side shake detection unit 15, and generates a shake target signal to be output to the camera side shake correction unit 14. The camera side shake correction unit 14 generates a drive command signal based on the shake target signal output from the camera control unit 5, and the image sensor 6 performs a shake correction operation by driving based on the drive command signal. The configuration in which the camera system control unit 5 generates the shake target signal will be described. The camera system control unit 5 includes a camera side filter processing unit 5a that performs filter processing on the corrected shake detection signal, a phase compensator 5b that performs phase compensation, and a gain compensator 5c. The characteristics of the camera side filter processing unit 5a are determined according to the characteristics of the camera side shake detection unit 15. The phase compensator 5b performs phase adjustment on the signal output from the camera side filter processing unit 5a. The gain compensator 5c performs gain processing by multiplying the signal output from the phase compensator 5b by a predetermined gain value, thereby generating a shake target signal and sending it to the camera side shake correction unit 14.

The camera system control unit 5 further includes a filter processing unit 5f that acquires the drive command signal generated by the camera-side shake correction unit 14 and performs filter processing on the acquired drive command signal, and a phase compensator 5d and a gain compensator 5e that perform phase compensation on the output of the filter processing unit 5f. Through these filter processing, phase compensation processing, and gain compensation processing, a signal corresponding to the vibration caused by the image sensor 6 being driven based on the previous drive command signal is acquired.

Then, adder 5g subtracts the drive command signal that has been signal-processed by filter processing unit 5f, phase compensator 5d, and gain compensator 5e from the shake detection signal output from camera-side shake detection unit 15 to correct the shake detection signal and generate a shake detection correction signal. A shake correction target signal is created based on this shake detection correction signal, and camera-side shake correction unit 14 generates a drive command signal, which drives image sensor 6 to perform shake correction operation. Details of the signal processing in drive command signal filter processing unit 5f, phase compensator 5d, and gain compensator 5e will be described using FIG. 3.

The effect of obtaining a shake detection and correction signal by subtracting a signal obtained by signal processing the drive command signal from the shake detection signal as shown in FIG. 2 will be described. There are cases where vibration caused by driving the image sensor 6 by a command from the shake correction unit 14 is transmitted to the camera-side shake detection unit 15. In such a case, a signal unrelated to camera shake is detected in the camera-side shake detection unit 15, and the image sensor 6 is driven accordingly, which may cause a problem that camera shake correction cannot be performed. In this embodiment, as described above, a signal corresponding to vibration caused by driving the image sensor 6 is obtained by processing from the filter processing unit 5f to the gain compensator 5d, and this is subtracted from the shake detection signal output from the camera-side shake detection unit 15. This makes it possible to reduce the influence of a signal unrelated to camera shake (a signal caused by driving the image sensor 6) and perform shake correction based on the shake target signal and the drive command signal.

This effect is not limited to handheld shooting. For example, as explained in FIG. 1, when shooting with the camera system mounted on a tripod, the vibration caused by driving the image sensor 6 causes the entire camera system to move around a fixed point on the tripod, making the above-mentioned problems likely to occur. Therefore, when the camera system detects that it is fixed to a tripod, it may be configured to process the shake detection signal output from the camera-side shake detection unit 15 in response to the drive command signal generated by the camera-side shake correction unit 14 as shown in FIG. 2, and generate a shake detection correction signal.

Next, using FIG. 3, we will explain the process of subtracting a signal corresponding to vibrations caused by the image sensor 6 being driven from the signal of the camera-side shake detection unit 15 based on the drive command signal to generate a shake detection correction signal.

Figure 3(a) shows the shake detection signal output from camera-side shake detection unit 15 during a certain period, and Figure 3(b) shows the output of the drive command signal generated by camera-side shake correction unit 14 during the same period. Note that in Figure 3, the output of a gyro sensor is used as the shake detection signal output from camera-side shake detection unit 15, but this is not limited as long as it detects the shake of the camera system, and similar processing may be performed using the output of an acceleration sensor. Figure 3(c) shows the state in which the drive command signal shown in Figure 3(b) is superimposed on the gyro signal shown in Figure 3(a), and Figure 3(d) shows the shake detection correction signal generated based on the previous drive command signal and current gyro signal shown in Figure 3(b).

3(a) shows an example of a blur detection signal 31 when a camera shake occurs at the timing of time 32 and the camera shake is input to the gyro sensor. FIG. 3(b) shows a drive command signal 33 generated by the camera-side blur correction unit 14 based on the blur detection signal 31 shown in FIG. 3(a) (shown by a dotted line in FIG. 3(b)). The drive command signal 33 is basically a signal proportional to the blur detection signal 31. FIG. 3(c) shows a blur detection signal 34. The blur detection signal 34 shows the output of the gyro sensor as in FIG. 3(a), but also shows how the vibration generated when the image sensor 6 is driven by the drive command signal 33 after time 35 affects the output of the gyro sensor (blur detection signal). FIG. 3(d) shows a phase adjustment signal 37 in which the phase of the drive command signal 33 is adjusted, a phase/gain adjustment signal 38 in which the gain of the phase adjustment signal 37 is further adjusted, and a blur detection correction signal 36 in which the blur detection signal 34 is corrected by the phase/gain adjustment signal 38. Phase adjustment signal 37 is the output of phase compensator 5d, and phase adjustment is performed to adjust the difference between time 32 and time 35. Phase/gain adjustment signal 38 is the output of gain compensator 5f.

As shown in FIG. 3(a), when a shake is input to the camera system and the shake is detected as shown in the shake detection signal 31, a drive command signal 33 as shown in FIG. 3(b) is output from the camera-side shake correction unit 14. The image sensor 6 is driven based on the drive command signal 33, but the vibration caused by this drive is also detected by the gyro sensor, and appears in the gyro sensor output 34 as shown in FIG. 3(c).

At the stage of generating the drive command signal 33, it is possible to anticipate changes in the output signal of the gyro sensor output 34 that will occur after time 35, so it is also possible to generate a phase adjustment signal 37 whose phase is adjusted to match time 35, and a phase/gain adjustment signal 38 whose gain is further adjusted. Then, by subtracting the phase/gain adjustment signal 38 from the shake detection signal 34, the camera system control unit 5 generates the shake detection correction signal 36.

When adjusting the gain, the gain may be adjusted based on the focal length of the camera system or the gravity of the drive unit that drives the image sensor 6. This is because the extent to which the camera system has an effect on the shake detection unit varies depending on the focal length of the camera system, and the magnitude of the vibration input to the shake detection unit varies depending on the weight of the drive unit. When the focal length is changeable (when the photographing optical system has a so-called zoom lens), the current focal length may be obtained from the lens device 2, and the gain compensator 5f may adjust the gain based on the focal length obtained from the lens device 2.

In addition, when generating the phase/gain adjustment signal 38, the signal may be passed through other filters in the camera-side filter unit 5f shown in FIG. 2.

The amount of phase to be adjusted when generating the phase/gain adjustment signal 38 and the gain magnification may be determined by determining a value according to the focal length at the design stage and referring to the value according to the focal length. The amount of phase and the magnification may be determined according to the attachment state of the accessory (type and weight of the accessory) as well as the focal length. For example, in the manufacturing process of the camera 1, a predetermined drive command signal may be given and the output of the camera shake detection unit 15 at that time may be monitored to determine the amount of phase and the magnification, thereby dealing with individual differences in the camera body 1.

As described above, by performing shake correction using the generated shake detection and correction signal, the effects of vibrations generated within the imaging device as a result of the imaging element 6 being driven can be reduced even if the vibrations are transmitted to the camera-side shake detection unit 15.

In this embodiment, correction is performed on one gyro sensor output, but many camera systems use multiple gyro sensors. By performing a similar correction on each gyro sensor output, it is possible to perform blur correction by further reducing the effects of vibrations that occur when the image sensor 6 is driven. Furthermore, if the lens device 2 also has a blur correction unit, the drive signal of the blur correction lens 3a may be acquired and the blur detection signal may be corrected based on the drive signal of the blur correction lens 3a as well in order to reduce the effects of vibrations that occur when the blur correction lens 3a is driven. The correction method is the same as the correction based on the drive signal of the image sensor, and involves subtracting a signal that has been adjusted in phase and gain from the drive signal on the lens side.

Next, the control flow of the blur correction using the image sensor 6 in this embodiment will be described with reference to FIG. 4. FIG. 4 is a control flowchart of the blur correction using the image sensor 6 in this embodiment, and this flow starts when the power of the imaging device 1 is turned on.

In step S4001, the camera system control unit 5 determines whether or not to use the shake detection and correction signal, and if so, proceeds to step S4002, otherwise proceeds to step S4005. In step S4001, whether or not to use the shake detection and correction signal is determined depending on whether or not it is expected that the vibrations caused by driving the image sensor 6 will be significantly affected by the detection result of the camera-side shake detection unit 15. For example, a tripod state determination unit that determines whether or not the camera system is mounted on a tripod may be provided, and the determination of whether or not to use the shake detection and correction signal may be made depending on the result of that determination. As described above, when mounted on a tripod, the camera is susceptible to the vibrations caused by driving the image sensor 6, so if it is determined that the camera is mounted on a tripod, proceed to step S4002, and if not, proceed to step S4005.

In step S4002, the camera system control unit 5 refers to the focal length of the camera system and the weight of the drive unit of the image sensor 6, and determines the gain adjustment value for generating the shake detection correction signal, that is, the gain to be multiplied by the gain compensator 5e, and proceeds to step S4003.

In step S4003, the camera system control unit 5 determines a phase adjustment value for generating a shake detection correction signal, in other words, the amount of phase to be adjusted by the phase compensator 5d, and proceeds to step S4004. Note that the gain and phase adjustment values determined in steps S4002 and S4003 may be values determined during manufacture of the camera system, or may be values determined for each shooting. If fixed values determined during manufacture of the camera system are used as adjustment values, steps S4002 and S4003 can be omitted.

In step S4004, the camera system control unit 5 generates a shake detection and correction signal (shake detection and correction signal 36 in FIG. 3(d)) based on the adjustment values determined in steps S4002 and S4003 and the shake detection signal output from the camera-side shake detection unit 15. Once the shake detection and correction signal has been generated, the process proceeds to step S4005.

In step S4005, the camera system control unit 5 generates a blur target signal based on the blur detection and correction signal, and outputs it to the camera side blur correction unit 14. The camera side blur correction unit 14 generates a drive command signal based on the blur target signal input from the camera system control unit 5, starts driving the image sensor 6, and proceeds to step S4006.

In step S4006, the camera system control unit 5 performs a shooting operation, and the process proceeds to step S4007. In step S4007, the camera system control unit 5 determines whether or not to end shooting based on user input, etc., and ends the flow if shooting is to end, and returns to step S4001 if not.

As described above, in this embodiment, signal processing is performed based on the drive command signal generated by the camera-side shake correction unit 14, and the signal is subtracted from the shake detection signal output by the camera-side shake detection unit 15 to remove signals unrelated to camera shake and generate a shake detection correction signal. By generating a drive command signal in the camera system control unit 5 and the camera-side shake correction unit 14 based on the shake detection correction signal, it becomes possible to perform appropriate shake correction.

Below, an imaging system according to a second embodiment of the present invention will be described with reference to Figures 5 and 6. This embodiment is an embodiment of an imaging system that is installed on a ceiling, wall, floor, etc., such as a surveillance camera.

Figure 5 describes the configuration of a surveillance camera that is installed so as to be suspended from the ceiling. The basic configuration is similar to that of Example 1 described using Figures 1 and 2, so only the differences will be described in detail.

In the first embodiment, a configuration was described that reduces the effect on the camera-side shake detection unit 15 of vibrations caused by the driving of the image sensor 6 by the camera-side shake correction unit 14. In this embodiment, a configuration is described that reduces the effect on the shake detection unit of vibrations caused by the driving of the pan-tilt head (pan-tilter), which is the base of the surveillance camera.

Fig. 5(a) is a schematic diagram of the imaging system in this embodiment, and Fig. 5(b) is a block diagram showing the electrical configuration of the imaging system. As shown in Fig. 5(a), the imaging system in this embodiment has a camera body 51 attached to a pan-tilt head 52 and receives pan-tilt drive. The camera body 51 comprises a camera system control unit 5, an image sensor 6, an image processing unit 7, and a memory unit 8. These configurations are the same as in the first embodiment. The camera body 51 in this embodiment further comprises an imaging optical system 3 having a blur correction lens 3a, a blur detection unit 56, a blur correction unit 57 that drives the image sensor 6 and the blur correction lens 3a, and a communication unit 53 that communicates with the pan-tilt head 52.

The pan-tilt head 52 includes a pan-tilt system control unit 54 that controls the driving of the pan-tilt head 52, and a pan-tilt drive unit that is controlled by the pan-tilt system control unit 54 and drives the pan-tilt head to pan and tilt the attached camera body 51.

If vibrations different from the movement (shake) of the camera body 51 are input to the shake detection unit 56 due to the driving of the pan-tilt head 52, the vibrations may drive the shake correction unit 57, reducing the accuracy of shake correction. In this embodiment, a drive command signal generated by the pan-tilt driving unit 55 is sent to the camera system control unit 5 via the pan-tilt system control unit 54 and the communication unit 53, and the camera system control unit 5 generates a shake detection correction signal as in the first embodiment. By driving the shake correction unit 57 using the shake detection correction signal, it is possible to reduce the effects of vibrations associated with pan-tilt driving.

The blur correction using the camera system control unit 5 and the blur correction unit 57 in this embodiment will be described with reference to FIG. 6. FIG. 6 is a block diagram of the blur correction system provided in the camera body 51. Basically, it is the same block diagram as in the first embodiment described with reference to FIG. 2, but only the different parts will be described in detail.

As shown in FIG. 6, in this embodiment, unlike the first embodiment shown in FIG. 2, the camera system control unit 5 obtains a drive command signal output from the pan/tilt system drive unit 55 via the pan/tilt system control unit 54 and the communication unit 53. Then, based on this drive command signal, the camera system control unit 5 corrects the shake detection signal output from the shake detection unit 56. The method of generating a shake detection correction signal for the shake detection signal output from the shake detection unit 56 is the same as in the first embodiment, so a description thereof will be omitted.

In this embodiment, a configuration has been described in which the effect of vibrations generated by pan-tilt driving using the pan-tilt head 52 on the detection results of the shake detection unit 56 is reduced, but other configurations are also possible. For example, the imaging system may be configured to include two shake correction units, and a drive command signal from one shake correction unit may be used to correct the detection signal from the shake detection unit for driving the other shake correction unit.

As described above, by performing signal processing based on the drive command signal generated by the pan/tilt drive unit 55, it is possible to obtain the influence of vibrations caused by the drive unit that performs shake correction. The shake correction unit 57 generates a drive command signal based on the shake detection correction signal obtained by subtracting the influence obtained from the output of the shake detection unit 56, making it possible to perform appropriate shake correction.

Below, an imaging system according to a third embodiment of the present invention will be described with reference to Figures 7 and 8. This embodiment is an embodiment of an imaging system that uses a device such as a gimbal stabilizer to which an imaging device is attached to correct large shakes.

Figure 7 describes a configuration in which a camera body is installed on a gimbal stabilizer (hereinafter, gimbal). The basic configuration is similar to that of Example 1 described using Figures 1 and 2, so only the differences will be described in detail.

In the first embodiment, a configuration was described that reduces the influence of vibrations caused by the driving of the image sensor 6 by the camera-side shake correction unit 14 on the camera-side shake detection unit 15. In this embodiment, a configuration is described that reduces the influence of vibrations caused by the driving of the gimbal 72 on the shake detection unit.

7(a) is a schematic diagram of the imaging system in this embodiment, and FIG. 7(b) is a block diagram showing the electrical configuration of the imaging system. As shown in FIG. 7(a), the imaging system in this embodiment is configured by a camera body 71 attached to a gimbal 72. The camera body 71 includes a camera system control unit 5, an imaging element 6, an image processing unit 7, a memory unit 8, and a display unit 9. These configurations are the same as those in the first embodiment. The camera body 51 in this embodiment further includes an imaging optical system 3 having a shake correction lens 3a, a shake detection unit 78, and a shake correction unit 79 that drives the imaging element 6 and the shake correction lens 3a. The camera body 51 further includes a camera-side operation detection unit 80 that detects user operations input via an operation unit (not shown) provided on the camera body, and a communication unit 73 that communicates with the gimbal 72.

The gimbal 72 includes a gimbal system control unit 74 that controls the driving of the gimbal 72, and a gimbal-side operation detection unit 75 that detects user operations input via an operation unit (not shown) provided on the gimbal 72. The gimbal 72 further includes a gimbal-side shake detection unit 76 that detects shake input to the gimbal 72, and a gimbal-side shake correction unit 77 that drives the gimbal 72.

If the vibrations caused by driving the gimbal 72 are detected by the shake detection unit 78 in the camera body 72, unintended shake correction, that is, a shake correction operation that attempts to correct the vibrations caused by driving the gimbal 72, is performed. This embodiment is configured to make it difficult for this unintended shake correction operation to occur.

If vibrations different from the movement (shake) of the camera body 71 are input to the shake detection unit 78 due to the driving of the gimbal 72, the vibrations may drive the shake correction unit 79, reducing the accuracy of shake correction. In this embodiment, a drive command signal generated by the gimbal side shake correction unit 77 is sent to the camera system control unit 5 via the gimbal system control unit 74 and the communication unit 73, and the camera system control unit 5 generates a shake detection correction signal as in the first embodiment. By driving the shake correction unit 79 using the shake detection correction signal, it is possible to reduce the effects of vibrations associated with driving the gimbal.

The blur correction using the camera system control unit 5 and the blur correction unit 79 in this embodiment will be described with reference to FIG. 8. FIG. 8 is a block diagram of the blur correction system provided in the camera body 71. Basically, this is the same block diagram as in the first embodiment described with reference to FIG. 2, but only the different parts will be described in detail.

As shown in FIG. 8, in this embodiment, unlike the first embodiment shown in FIG. 2, the camera system control unit 5 obtains the drive command signal output from the gimbal side shake correction unit 77 via the gimbal system control unit 74 and the communication unit 73. Then, the camera system control unit 5 corrects the shake detection signal output from the shake detection unit 79 based on this drive command signal.

The method of generating the shake detection correction signal from the shake detection signal output from the shake detection unit 78 is the same as in Example 1, and therefore will not be described here. In this example, a form for reducing the effect on the detection result of the shake detection unit 78 caused by vibrations generated by driving the gimbal 72 has been described, but other configurations are also possible. For example, as in Example 1, a configuration may be used that reduces the effect on the gimbal side shake detection unit 76 caused by vibrations generated by driving the gimbal 72. In this case, the shake detection signal output from the gimbal side shake detection unit 76 and the shake detection signal output from the shake detection unit 78 (on the camera body side) may be corrected based on the drive command signal from the gimbal side shake correction unit 77, and two shake detection correction signals may be generated.

As described above, the influence of vibrations caused by driving the drive unit that performs shake compensation can be obtained by performing signal processing based on the drive command signal generated by the gimbal-side shake compensation unit 77. The shake compensation unit 79 generates a drive command signal based on the shake detection and compensation signal obtained by subtracting this influence from the output of the shake detection unit 78, making it possible to perform appropriate shake compensation.

The above describes preferred embodiments of the present invention, but the present invention is not limited to these embodiments, and various modifications and variations are possible within the scope of the gist of the invention.

3 Photographing optical system 5 Camera system control unit 6 Image sensor 12 Lens system control unit 13 Lens side blur correction unit 14 Camera side blur correction unit 15 Camera side blur detection unit 16 Lens side blur detection unit

Claims (10)

an acquisition means for acquiring a shake detection signal of the imaging device from the shake detection means;
a shake correction control means for acquiring a drive command signal for a shake correction means based on the shake detection signal acquired from the shake detection means, and controlling shake correction by outputting a drive signal to the shake correction means,
The blur correction control device according to claim 1, wherein the blur correction control means obtains a current drive command signal based on the blur detection signal and the previous drive command signal. The blur correction control device according to claim 1, characterized in that the blur correction control means obtains the current drive command signal by subtracting the previous drive command signal from the blur detection signal. The blur correction control device according to claim 1, characterized in that the blur correction control means obtains the current drive command signal based on the blur detection signal and a signal obtained by adjusting the phase of the previous drive command signal. The image stabilization control device according to claim 2, characterized in that the image stabilization control means obtains the current drive command signal by subtracting a signal obtained by adjusting the previous drive command signal based on the focal length of the photographing optical system of the imaging device from the image stabilization detection signal. The blur correction control device according to claim 2, characterized in that the blur correction control means adjusts the phase of the previous drive command signal, and subtracts the signal multiplied by a gain from the blur detection signal to obtain the current drive command signal. The image stabilization control device according to claim 5, characterized in that the gain is changed according to the focal length of the imaging optical system of the imaging device. The image stabilization control device according to claim 5, characterized in that the gain is changed according to the lens device attached to the imaging device. a tripod state determination means for determining whether the imaging device is mounted on a tripod;
2. The image stabilization control device according to claim 1, wherein the image stabilization control means performs image stabilization control based on a blur detection signal obtained from the image stabilization means, a drive command signal for the image stabilization means, and a blur detection and correction signal calculated in accordance with a result of determination by the tripod state determination means. A blur correction control device according to any one of claims 1 to 8,
an image sensor that captures subject light from an imaging optical system;
an imaging apparatus comprising: An acquisition step of acquiring a shake detection signal of an imaging device;
a control step of acquiring a drive command signal for the shake correction means based on the acquired shake detection signal, and controlling shake correction by outputting a drive signal to the shake correction means, wherein in the control step, a current drive command signal is acquired based on the shake detection signal and the previous drive command signal.

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