Imaging device

Abstract

To provide an imaging apparatus, an operation method of the imaging apparatus and a program which can achieve both of suppression of shake of an image following vibration of a mechanical shutter and suppression of the uncomfortable feeling given to a user.SOLUTION: A processor of an imaging apparatus is configured to: perform, based on vibration of the imaging apparatus, movement control of moving an image sensor in a direction in which shake of an image, which is obtained by imaging performed by the image sensor, is corrected; and perform, in the imaging performed by the image sensor, gain-up control of increasing a gain of the movement control in a case where a shutter speed of the mechanical shutter is shorter than a first default time compared to a case where the shutter speed of the mechanical shutter is longer than the first default time.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The technology of the present disclosure relates to an imaging device.

Background Art

[0002] The imaging device disclosed in Japanese Unexamined Patent Application Publication No. 2009-63664 includes a feedback gain control unit that gradually controls the gain setting of the feedback path from the position detection unit to the drive control unit according to the shutter speed of the imaging unit during the imaging operation by the imaging unit. The feedback gain control unit of Patent Document 1 sets the gain to a high level when the shutter speed of the imaging unit is high during the imaging operation by the imaging unit, and sets the gain to a low level when the shutter speed of the imaging unit is low.

[0003] The imaging device disclosed in Japanese Unexamined Patent Application Publication No. 2009-168938 includes a feedback gain control unit that controls the gain of the feedback path from the position detection unit to the drive control unit according to the shutter speed of the imaging unit. The feedback gain control unit of Patent Document 2 sets the gain to a high level when the shutter speed of the imaging unit is high, sets the gain to a medium level when the shutter speed of the imaging unit is medium, and sets the gain to a low level when the shutter speed of the imaging unit is low.

Summary of the Invention

[0004] One embodiment according to the technology of the present disclosure provides, as one aspect, an imaging device, an operating method of the imaging device, and a program that can achieve both suppression of image blurring associated with the vibration of a mechanical shutter and suppression of discomfort given to a user.

Means for Solving the Problems

[0005] A first aspect of the technology of this disclosure is an imaging device comprising a mechanical shutter, an image sensor, and a processor, wherein the processor performs movement control to move the image sensor in a direction that corrects blur in the image obtained by imaging with the image sensor, based on vibrations of the imaging device, and in imaging with the image sensor, when the shutter speed of the mechanical shutter is shorter than a first predetermined time, the processor performs gain-up control to increase the gain of the movement control compared to when the shutter speed of the mechanical shutter is longer than a first predetermined time.

[0006] A second aspect of the technology of this disclosure is an imaging apparatus according to the first aspect, wherein the processor performs gain-up control when the shutter speed of the mechanical shutter is shorter than a first predetermined time and longer than a second predetermined time during imaging by the image sensor.

[0007] A third aspect of the technology of this disclosure is an imaging apparatus according to the first or second aspect, wherein the processor performs gain-up control in a mechanical shutter mode in which the rear curtain of the mechanical shutter is driven after the front curtain of the mechanical shutter has been driven.

[0008] A fourth aspect of the technology of this disclosure is an imaging device relating to any one of the first to third aspects, wherein the processor controls the gain of the movement control to a gain lower than the gain set by the gain-up control in the electronic shutter mode for operating the electronic shutter.

[0009] A fifth aspect of the technology of this disclosure is an imaging device relating to any one of the first to fourth aspects, wherein the processor performs gain-up control when continuous imaging by the image sensor is performed in an electronic front curtain shutter mode in which the rear curtain of the mechanical shutter is driven after the electronic front curtain of the image sensor is activated.

[0010] A sixth aspect of the technology of this disclosure is an imaging device according to any one of the first to fifth aspects, wherein, in imaging by an image sensor, if the shutter speed of the mechanical shutter is longer than a first predetermined time, the processor performs a low-pass filter on the signal obtained due to the vibration of the imaging device at a predetermined cutoff frequency, and performs movement control based on the low-pass filtered signal.

[0011] A seventh aspect of the technology of this disclosure is an imaging device relating to any one of the first to sixth aspects, wherein the processor performs gain-up control when the frequency of the drive signal for motion control is a second frequency that is higher than the first frequency.

[0012] An eighth aspect of the technology of this disclosure is an imaging device relating to any one of the first to seventh aspects, wherein the first predetermined time is 1 / 4 second.

[0013] A ninth aspect of the technology of this disclosure is an imaging device relating to any one of the first to seventh aspects, wherein the first predetermined time is 1 / 8 second.

[0014] A tenth aspect of the technology of this disclosure is an imaging device relating to the second aspect and any one of the third to ninth aspects dependent on the second aspect, wherein the second predetermined time is 1 / 60 second.

[0015] An eleventh aspect of the technology of this disclosure is an imaging device relating to the second aspect and any one of the third to ninth aspects dependent on the second aspect, wherein the second default time is 1 / 30 second.

[0016] A twelfth aspect of the technology of this disclosure is an imaging device relating to any one of the first to eleventh aspects, further comprising an actuator for moving an image sensor, wherein the actuator has a first actuator and a second actuator, and the processor provides a phase difference between a first drive signal for driving the first actuator and a second drive signal for driving the second actuator.

[0017] A thirteenth aspect of the technology of this disclosure is an imaging device according to the twelfth aspect, wherein the first drive signal and the second drive signal are PWM signals, respectively.

[0018] A fourteenth aspect of the technology of this disclosure is an imaging device relating to any one of the first to thirteenth aspects, further comprising an actuator for moving an image sensor, wherein the actuator has a first voice coil motor and a second voice coil motor arranged side by side, the first voice coil motor having a first coil and a first magnet, the second voice coil motor having a second coil and a second magnet, the winding direction of the first coil being opposite to the winding direction of the second coil, and the north and south poles of the first magnet being arranged opposite to the north and south poles of the second magnet.

[0019] A fifteenth aspect of the technology of the present disclosure is a method for operating an imaging device comprising a mechanical shutter and an image sensor, the method comprising: performing movement control to move the image sensor in a direction that corrects blur in the image obtained by imaging with the image sensor based on vibration of the imaging device; and, in imaging with the image sensor, performing gain-up control to increase the gain of the movement control compared to when the shutter speed of the mechanical shutter is shorter than a first predetermined time.

[0020] A 16th aspect of the technology of the present disclosure is a program for causing a computer applied to an imaging device including a mechanical shutter and an image sensor to perform movement control for moving the image sensor in a direction in which blur of an image obtained by imaging with the image sensor is corrected based on vibration of the imaging device, and to perform gain-up control for increasing a gain of the movement control when a shutter speed of the mechanical shutter is shorter than a first predetermined time compared to when the shutter speed of the mechanical shutter is longer than the first predetermined time, in imaging by the image sensor.

Brief Description of Drawings

[0021] [Figure 1] FIG. 8 is a perspective view showing an example of an appearance of an imaging device according to an embodiment of the technology of the present disclosure. [Figure 2] FIG. 11 is a rear view showing an example of an appearance of the back side of the imaging device shown in FIG. 1. [Figure 3] FIG. 14 is a schematic configuration diagram showing an example of a hardware configuration of the imaging device shown in FIG. 1. [Figure 4] FIG. 17 is a block diagram showing an example of a configuration of a feedback circuit shown in FIG. 3. [Figure 5] FIG. 20 is a block diagram showing an example of a main part function of the CPU shown in FIG. 3. [Figure 6] FIG. 23 is a conceptual diagram showing an example of processing of a low-pass filter processing unit shown in FIG. 5. [Figure 7] FIG. 26 is a conceptual diagram showing an example of processing of a drive control unit and a phase control unit shown in FIG. 5. [Figure 8] FIG. 29 is a conceptual diagram showing an example of processing of a drive control unit, a shutter speed determination unit, and a gain control unit shown in FIG. 5. [Figure 9] FIG. 32 is a conceptual diagram showing an example of processing of a drive control unit and a gain control unit shown in FIG. 5. [Figure 10] FIG. 35 is a conceptual diagram showing an example of processing of a shutter mode determination unit shown in FIG. 5. [Figure 11] FIG. 38 is a conceptual diagram showing an example of processing of a gain control unit shown in FIG. 5. [Figure 12] It is a flowchart showing an example of the flow of the gain control process of the CPU shown in FIG. 5. [Figure 13] It is an exploded perspective view showing an example of the shake correction mechanism mounted on the imaging device shown in FIG. 1. [Figure 14] It is a front view showing an example of the movable member shown in FIG. 13. [Figure 15] It is a front view showing an example of the first fixing member shown in FIG. 13. [Figure 16] It is a front view showing an example of the second fixing member shown in FIG. 13. [Figure 17] It is a bottom view showing an example of the third VCM and the fourth VCM shown in FIG. 13. [Figure 18] It is a conceptual diagram showing a modified example of the processing of the gain control unit shown in FIG. 9. [Figure 19] It is a block diagram showing an example of the first modified embodiment of the imaging device shown in FIG. 1. [Figure 20] It is a block diagram showing an example of the second modified embodiment of the imaging device shown in FIG. 1.

Embodiments for Carrying Out the Invention

[0022] Hereinafter, an example of an embodiment of an imaging device, an operation method of the imaging device, and a program according to the technology of the present disclosure will be described with reference to the accompanying drawings.

[0023] First, the terms used in the following description will be described.

[0024] CPU stands for "Central Processing Unit". NVM stands for "Non-Volatile Memory". RAM stands for "Random Access Memory". AE stands for "Auto Exposure". AF stands for "Auto Focus". MF stands for "Manual Focus". PID stands for "Proportional Integral Differential". VCM stands for "Voice Coil Motor". I / F stands for "Interface". UI stands for "User Interface". CMOS stands for "Complementary Metal Oxide Semiconductor". CCD stands for "Charge Coupled Device". GPU stands for "Graphics Processing Unit". IC stands for "Integrated Circuit". ASIC stands for "Application Specific Integrated Circuit". PLD stands for "Programmable Logic Device". FPGA stands for "Field-Programmable Gate Array". SoC stands for "System-on-a-chip". SSD stands for "Solid State Drive". USB stands for "Universal Serial Bus". HDD stands for "Hard Disk Drive". EEPROM stands for "Electrically Erasable and Programmable Read Only Memory". EL stands for "Electro-Luminescence". LAN stands for "Local Area Network". WAN stands for "Wide Area Network". IIR stands for "Infinite Impulse Response". PWM stands for "Pulse Width Modulation".

[0025] In this specification, “perpendicular” means not only perfect perpendicularity but also an error that is generally acceptable in the art to which the disclosed technology belongs, provided that the error is not contrary to the spirit of the disclosed technology. In this specification, “identical” means not only perfect identicality but also an error that is generally acceptable in the art to which the disclosed technology belongs, provided that the error is not contrary to the spirit of the disclosed technology. In this specification, “parallel” means not only perfect parallelism but also an error that is generally acceptable in the art to which the disclosed technology belongs, provided that the error is not contrary to the spirit of the disclosed technology.

[0026] (Imaging device 10) As an example, the imaging device 10 shown in Figure 1 is a device for capturing images of a subject. In the example shown in Figure 1, a lens-interchangeable digital camera is shown as an example of the imaging device 10. The imaging device 10 comprises an imaging device body 12 and an interchangeable lens 14. The interchangeable lens 14 is interchangeably mounted on the imaging device body 12. The interchangeable lens 14 is provided with a focus ring 16. The focus ring 16 is operated by the user of the imaging device 10 (hereinafter simply referred to as "user") when the user manually adjusts the focus on the subject using the imaging device 10.

[0027] In this embodiment, the imaging device 10 is exemplified as a digital camera with interchangeable lenses, but this is merely one example. It could also be a digital camera with a fixed lens, or a digital camera built into various electronic devices such as smart devices, wearable terminals, cell observation devices, ophthalmic observation devices, or surgical microscopes.

[0028] In Figure 1, the P-axis corresponds to the pitch axis of the imaging device 10, the Y-axis corresponds to the yaw axis of the imaging device 10, and the R-axis corresponds to the roll axis of the imaging device 10. Hereafter, the direction along the P-axis will be referred to as the P-axis direction, the direction along the Y-axis as the Y-axis direction, and the direction along the R-axis as the R-axis direction. The P-axis direction, Y-axis direction, and R-axis direction are orthogonal to each other.

[0029] The imaging device body 12 is equipped with an image sensor 18. The image sensor 18 is a CMOS image sensor. The image sensor 18 captures an imaging range that includes at least one subject. When the interchangeable lens 14 is attached to the imaging device body 12, subject light indicating the subject passes through the interchangeable lens 14 and is imaged by the image sensor 18, and image data indicating the image of the subject is generated by the image sensor 18.

[0030] In this embodiment, a CMOS image sensor is given as an example of the image sensor 18, but the technology of this disclosure is not limited to this, and the technology of this disclosure can be established even if the image sensor 18 is another type of image sensor such as a CCD image sensor.

[0031] A release button 20 and a dial 22 are provided on the top surface of the imaging device body 12. The dial 22 is operated when setting the operating mode of the imaging system and the operating mode of the playback system, and when the dial 22 is operated, the imaging device 10 selectively sets the operating mode to either imaging mode or playback mode.

[0032] The release button 20 functions as both an image preparation instruction unit and an image acquisition instruction unit, and can detect two stages of pressing: an image preparation instruction state and an image acquisition instruction state. The image preparation instruction state refers to the state in which the button is pressed from, for example, the standby position to an intermediate position (half-press position), and the image acquisition instruction state refers to the state in which the button is pressed to the final pressed position (full-press position).

[0033] In the following, the state in which the button is pressed from the standby position to the half-press position will be referred to as the "half-press state," and the state in which the button is pressed from the standby position to the fully-press position will be referred to as the "fully-pressed state." Depending on the configuration of the imaging device 10, the imaging preparation instruction state may be the state in which the user's finger is in contact with the release button 20, and the imaging instruction state may be the state in which the operating user's finger has moved away from the state in which it was in contact with the release button 20.

[0034] As an example, as shown in Figure 2, a touch panel display 24 and instruction keys 26 are provided on the back of the imaging device body 12.

[0035] The touch panel display 24 comprises a display 28 and a touch panel 30. An example of the display 28 is an EL display (for example, an organic EL display or an inorganic EL display). The display 28 may be other types of displays, such as a liquid crystal display, instead of an EL display 28.

[0036] The display 28 displays images and / or text information. When the imaging device 10 is in imaging mode, the display 28 is used to display the live view image obtained by imaging for the live view image, that is, by continuous imaging. The imaging performed to obtain the live view image (hereinafter also referred to as "imaging for the live view image") is performed according to a frame rate of, for example, 60fps. 60fps is merely an example; the frame rate may be less than 60fps or more than 60fps.

[0037] Here, "live view image" refers to a moving image for display based on image data obtained by capturing images with the image sensor 18.

[0038] The display 28 is also used to display still images obtained when the imaging device 10 is instructed to take still images via the release button 20. The display 28 is also used to display playback images when the imaging device 10 is in playback mode. Furthermore, when the imaging device 10 is in setting mode, the display 28 is used to display a menu screen where various menus can be selected, and a setting screen for setting various setting values ​​used in control related to imaging.

[0039] The touch panel 30 is a transmissive touch panel and is superimposed on the surface of the display area of ​​the display 28. The touch panel 30 receives user input by detecting contact with an object such as a finger or stylus pen. For the sake of explanation, the "fully pressed state" described above also includes the state in which the user has turned on the soft key for starting image capture via the touch panel 30.

[0040] In this embodiment, an out-cell type touch panel display in which the touch panel 30 is superimposed on the surface of the display area of ​​the display 28 is given as an example of the touch panel display 24, but this is merely one example. For example, an on-cell type or in-cell type touch panel display can also be used as the touch panel display 24.

[0041] The instruction key 26 accepts various instructions. Here, "various instructions" refers to various instructions such as switching the image stabilization mode on and off, displaying the menu screen, selecting one or more menus, confirming the selection, deleting the selection, zooming in, zooming out, and frame by frame. These instructions may also be given via the touch panel 30.

[0042] As an example, as shown in Figure 3, the image sensor 18 has a light-receiving surface 18A. The image sensor 18 is, for example, a photoelectric conversion element. The image sensor 18 is sometimes referred to as a solid-state image sensor. As an example, the image sensor 18 is positioned within the imaging device body 12 such that the center of the light-receiving surface 18A coincides with the optical axis OA of the interchangeable lens 14.

[0043] The image sensor 18 may be a monochrome image sensor or a color image sensor in which multiple physical pixels are assigned color filters of different colors. The image sensor 18 has multiple photosensitive pixels arranged in a matrix, and the light-receiving surface 18A is formed by multiple photosensitive pixels. Each photosensitive pixel is a physical pixel having a photodiode (not shown), which converts received light into photoelectric signals and outputs an electrical signal corresponding to the amount of light received.

[0044] (Interchangeable lens 14) The interchangeable lens 14 includes an imaging lens 40. The imaging lens 40, as an example, has an objective lens 42, a focusing lens 44, a zoom lens 46, and an aperture 48. The objective lens 42, focusing lens 44, zoom lens 46, and aperture 48 are arranged in that order along the optical axis OA from the subject side to the imaging device body 12 side.

[0045] The interchangeable lens 14 also includes a control device 50, a focus actuator 52, a zoom actuator 54, and an aperture actuator 56. The control device 50 controls the entire interchangeable lens 14 according to instructions from the imaging device body 12. The control device 50 is, for example, a device having a computer including a CPU, NVM, and RAM. Although a computer is used as an example here, this is merely one example, and devices including ASICs, FPGAs, and / or PLDs may also be used. Furthermore, the control device 50 may be a device realized by, for example, a combination of hardware and software configurations.

[0046] The focusing actuator 52 includes a focusing slide mechanism (not shown) and a focusing motor (not shown). A focusing lens 44 is mounted on the focusing slide mechanism so as to be slidable along the optical axis OA. A focusing motor is also connected to the focusing slide mechanism, and the focusing slide mechanism operates by receiving power from the focusing motor, thereby moving the focusing lens 44 along the optical axis OA.

[0047] The zoom actuator 54 includes a zoom slide mechanism (not shown) and a zoom motor (not shown). A zoom lens 46 is mounted on the zoom slide mechanism so as to be slidable along the optical axis OA. A zoom motor is also connected to the zoom slide mechanism, and the zoom slide mechanism operates by receiving power from the zoom motor, thereby moving the zoom lens 46 along the optical axis OA.

[0048] The aperture actuator 56 includes a power transmission mechanism (not shown) and an aperture motor (not shown). The aperture 48 has an opening 48A, and the size of the opening 48A is variable. The opening 48A is formed by a plurality of aperture blades 48B. The plurality of aperture blades 48B are connected to the power transmission mechanism. An aperture motor is also connected to the power transmission mechanism, and the power transmission mechanism transmits the power of the aperture motor to the plurality of aperture blades 48B. The plurality of aperture blades 48B change the size of the opening 48A by operating in response to the power transmitted from the power transmission mechanism. The aperture 48 adjusts the exposure by changing the size of the opening 48A.

[0049] The focus motor, zoom motor, and aperture motor (none of which are shown) are connected to the control device 50, and the control device 50 controls the drive of each of these motors. In this embodiment, stepping motors are used as examples of the focus motor, zoom motor, and aperture motor. Therefore, the focus motor, zoom motor, and aperture motor operate in synchronization with pulse signals in response to commands from the control device 50.

[0050] In this example, a focus motor, zoom motor, and aperture motor are provided on the interchangeable lens 14. However, this is merely one example, and at least one of the focus motor, zoom motor, and aperture motor may be provided on the imaging device body 12. Furthermore, the components and / or operating method of the interchangeable lens 14 can be changed as needed.

[0051] In the imaging device 10, when in imaging mode, MF mode and AF mode are selectively set according to instructions given to the imaging device body 12. MF mode is an operation mode in which the focus is adjusted manually. In MF mode, for example, the user operates the focus ring 16, etc., and the focus lens 44 moves along the optical axis OA by an amount of movement corresponding to the amount of operation of the focus ring 16, etc., thereby adjusting the focus.

[0052] In AF mode, the imaging device body 12 calculates the focus position according to the subject distance and adjusts the focus by moving the focus lens 44 toward the calculated focus position. Here, the focus position refers to the position of the focus lens 44 on the optical axis OA when the focus is correct. For the sake of explanation, the control that aligns the focus lens 44 to the focus position will also be referred to as "AF control" below.

[0053] (Imaging device main unit 12) As an example, as shown in Figure 3, the imaging device body 12 includes an image sensor 18, an image sensor driver 60, a signal processing circuit 62, a mechanical shutter 64, a shutter actuator 66, a shutter driver 68, a vibration sensor 70, a blur correction mechanism 72, a feedback circuit 74, a blur correction driver 76, a controller 78, an image memory 80, a UI system device 82, an external I / F 84, and an input / output I / F 86.

[0054] The input / output interface 86 is connected to an image sensor driver 60, a signal processing circuit 62, a shutter driver 68, a feedback circuit 74, a blur correction driver 76, a controller 78, an image memory 80, a UI device 82, and an external interface 84. The input / output interface 86 is also connected to a control device 50 for the interchangeable lens 14.

[0055] The controller 78 includes a CPU 90, an NVM 92, and RAM 94. The CPU 90, NVM 92, and RAM 94 are connected via a bus 96, which is connected to an input / output interface 86.

[0056] In the example shown in Figure 3, for illustrative purposes, a single bus is depicted as bus 96, but multiple buses are also possible. Bus 96 may be a serial bus, or a parallel bus including a data bus, address bus, and control bus, etc.

[0057] NVM92 is a non-temporary storage medium that stores various parameters and programs. For example, NVM92 is an EEPROM. However, this is merely one example, and an HDD and / or SSD may be used as NVM92 instead of, or in conjunction with, an EEPROM. RAM94 temporarily stores various information and is used as work memory.

[0058] The CPU 90 reads the necessary program from the NVM 92 and executes the read program in the RAM 94. The CPU 90 controls the entire imaging device 10 according to the program executed on the RAM 94. In the example shown in Figure 3, the image sensor driver 60, shutter driver 68, feedback circuit 74, blur correction driver 76, image memory 80, UI device 82, external I / F 84, and control device 50 are controlled by the CPU 90.

[0059] An image sensor driver 60 is connected to the image sensor 18. The image sensor driver 60 supplies imaging timing signals, which define the timing of imaging performed by the image sensor 18, to the image sensor 18 according to instructions from the CPU 90. The image sensor 18 performs reset, exposure, and outputs electrical signals according to the imaging timing signals supplied by the image sensor driver 60. Examples of imaging timing signals include a vertical synchronization signal and a horizontal synchronization signal.

[0060] When the interchangeable lens 14 is attached to the imaging device body 12, the subject light incident on the imaging lens 40 is imaged onto the light-receiving surface 18A by the imaging lens 40. Under the control of the image sensor driver 60, the image sensor 18 converts the subject light received by the light-receiving surface 18A into photoelectric signals and outputs an electrical signal corresponding to the amount of subject light as analog image data representing the subject light to the signal processing circuit 62. Specifically, the signal processing circuit 62 reads out the analog image data from the image sensor 18 in units of one frame and for each horizontal line using an exposure sequential readout method.

[0061] The signal processing circuit 62 generates digital image data by digitizing analog image data. For the sake of explanation, in the following, when it is not necessary to distinguish between the digital image data that is processed internally by the imaging device body 12 and the image shown by the digital image data (i.e., the image that is visualized based on the digital image data and displayed on the display 28, etc.), the term "imaging image" will be used.

[0062] The image memory 80 stores the captured image generated by the signal processing circuit 62. In other words, the signal processing circuit 62 causes the image memory 80 to store the captured image. The CPU 90 retrieves the captured image from the image memory 80 and performs various processes using the retrieved image.

[0063] The UI device 82 includes a display 28, and the CPU 90 displays various information on the display 28. The UI device 82 also includes a reception device 83. The reception device 83 includes a touch panel 30 and a hard key section 31. The hard key section 31 consists of multiple hard keys, including an instruction key 26 (see Figure 1). The CPU 90 operates according to the various instructions received by the touch panel 30. Although the hard key section 31 is included in the UI device 82 here, the technology of this disclosure is not limited to this, and for example, the hard key section 31 may be connected to an external I / F 84.

[0064] The external I / F84 is responsible for the exchange of various types of information between the imaging device 10 and devices located outside of it (hereinafter also referred to as "external devices"). An example of the external I / F84 is a USB interface. External devices such as smart devices, personal computers, servers, USB memory, memory cards, and / or printers (not shown) can be directly or indirectly connected to the USB interface.

[0065] The mechanical shutter 64 is, for example, a focal-plane shutter and is positioned between the aperture 48 and the light-receiving surface 18A. The mechanical shutter 64 comprises a front curtain 64A and a rear curtain 64B. For example, each of the front curtain 64A and the rear curtain 64B comprises multiple blades. The front curtain 64A is positioned closer to the subject than the rear curtain 64B.

[0066] The shutter actuator 66 is an actuator having a link mechanism (not shown), a front curtain solenoid (not shown), and a rear curtain solenoid (not shown). The front curtain solenoid is the drive source for the front curtain 64A and is mechanically connected to the front curtain 64A via the link mechanism. The rear curtain solenoid is the drive source for the rear curtain 64B and is mechanically connected to the rear curtain 64B via the link mechanism. The shutter driver 68 controls the shutter actuator 66 according to instructions from the CPU 90.

[0067] The front curtain solenoid generates power under the control of the shutter driver 68 and applies the generated power to the front curtain 64A to selectively wind up and down the front curtain 64A. The rear curtain solenoid generates power under the control of the shutter driver 68 and applies the generated power to the rear curtain 64B to selectively wind up and down the rear curtain 64B. In the imaging device 10, the opening and closing of the front curtain 64A and the opening and closing of the rear curtain 64B are controlled by the CPU 90, thereby controlling the amount of exposure to the image sensor 18.

[0068] In the imaging device 10, imaging for live view images and imaging for recording still images and / or moving images are performed using a sequential exposure readout method (rolling shutter method). The image sensor 18 has an electronic shutter function, and imaging for live view images is achieved by operating the electronic shutter without driving the mechanical shutter 64 while it is in the fully open position.

[0069] In contrast, imaging with exposure, i.e., imaging for still images, is achieved by operating the electronic shutter and driving the mechanical shutter 64 to transition from the front curtain closed state to the rear curtain closed state. The imaging device 10 also has an electronic front curtain shutter function. The electronic front curtain shutter function is achieved by operating the electronic shutter as an electronic front curtain while keeping the front curtain 64A open, and driving the image sensor 18 and the mechanical shutter 64 to transition the rear curtain 64B to the closed state.

[0070] The vibration sensor 70 is, for example, a gyro sensor and detects vibrations of the imaging device 10. The gyro sensor included in the vibration sensor 70 detects vibrations around the P-axis, Y-axis, and R-axis. The vibration sensor 70 detects vibrations in the P-axis direction and the Y-axis direction by converting the vibrations around the P-axis and Y-axis detected by the gyro sensor into vibrations in a two-dimensional plane parallel to the P-axis and Y-axis. The vibration sensor 70 outputs a P-axis angular velocity signal corresponding to vibrations in the P-axis direction, a Y-axis angular velocity signal corresponding to vibrations in the Y-axis direction, and an R-axis angular velocity signal corresponding to vibrations around the R-axis. The P-axis angular velocity signal is a signal indicating the angular velocity around the P-axis, the Y-axis angular velocity signal is a signal indicating the angular velocity around the Y-axis, and the R-axis angular velocity signal is a signal indicating the angular velocity around the R-axis. In the following, for the sake of convenience, if it is not necessary to distinguish between the P-axis angular velocity signal, the Y-axis angular velocity signal, and the R-axis angular velocity signal, they will be collectively referred to as "angular velocity signals."

[0071] The image blur correction mechanism 72 is integrated with the image sensor 18. The image blur correction mechanism 72 corrects image blur when blur occurs in the image obtained by the image sensor 18 due to vibration of the imaging device 10 by moving the image sensor 18 in a direction that corrects the image blur.

[0072] Here, "image blur" refers to the phenomenon in which the subject image shifts from its reference position due to the tilting of the optical axis OA in conjunction with the vibration phenomenon of the imaging device 10, that is, the phenomenon in which the subject image shifts from its reference position due to the relative movement of the optical axis OA with respect to the subject. "Vibration phenomenon" refers to the phenomenon in which the interchangeable lens 14 vibrates due to vibrations being transmitted to the interchangeable lens 14 from outside and / or inside the imaging device 10.

[0073] Furthermore, "the optical axis OA is tilted" means, for example, that the optical axis OA is tilted with respect to the reference axis (for example, the optical axis OA before the vibration phenomenon occurs (i.e., the optical axis OA when the imaging device 10 is stationary)). "Reference position" refers to, for example, the position of the subject image obtained when no vibration is applied to the interchangeable lens 14 (for example, the position of the subject image within the light-receiving surface 18A).

[0074] "Correcting image blur" includes not only matching the position of the image blurred by the vibration of the imaging device 10 to the position of the image before the vibration acted on the imaging device 10, but also bringing the position of the image blurred by the vibration of the imaging device 10 closer to the position of the image before the vibration acted on the imaging device 10.

[0075] The image stabilization mechanism 72 includes a position sensor 100 and an image stabilization actuator 102. The position sensor 100 includes, for example, a Hall element and a sensor magnet, and detects the position of the image sensor 18 in the P-axis direction, the Y-axis direction, and the position around the R-axis. The position sensor 100 outputs a P-axis position detection signal corresponding to the position of the image sensor 18 in the P-axis direction, a Y-axis position detection signal corresponding to the position in the Y-axis direction, and an R-axis position detection signal corresponding to the position around the R-axis. In the following explanation, for convenience, when it is not necessary to distinguish between the P-axis position detection signal, the Y-axis position detection signal, and the R-axis position detection signal, they will be collectively referred to as "position detection signals".

[0076] The image stabilization actuator 102 includes, for example, a voice coil motor and is driven in accordance with a drive signal output from the image stabilization driver 76. The image stabilization actuator 102 moves the image sensor 18 in the P-axis direction and the Y-axis direction, and rotates the image sensor 18 around the R-axis. The image stabilization actuator 102 is an example of an "actuator for moving an image sensor" according to the technology of this disclosure. Details of the image stabilization mechanism 72, including the position sensor 100 and the image stabilization actuator 102, will be described later.

[0077] The feedback circuit 74 feeds back the vibration detection results from the vibration sensor 70 and the position detection results from the position sensor 100 to the shake correction driver 76. The details of the feedback circuit 74 are described below.

[0078] (Processor 220, CPU 90, and feedback circuit 74) As an example, as shown in Figure 4, the imaging device 10 (see Figures 1 to 3) includes a processor 220. The processor 220 includes a CPU 90 and a feedback circuit 74. The processor 220 is an example of a "processor" according to the technology of this disclosure. The feedback circuit 74 includes a high-pass filter 112, an amplifier 114, an A / D converter 116, an averager circuit 118, a subtractor 120, a long-time integrator 122, a coring circuit 124, an integrator 126, a phase compensator 128, a multiplier 130, an adder 132, a subtractor 134, an amplifier 136, an A / D converter 138, a current position converter 140, a filter calculator 142, and a control output calculator 144.

[0079] The high-pass filter 112 extracts high-frequency components (for example, frequency components predetermined as high-frequency noise) from the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal output from the vibration sensor 70. The amplifier 114 amplifies the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal from which the high-frequency components have been extracted by the high-pass filter 112. The A / D converter 116 converts the analog signals P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal, which have been amplified by the amplifier 114, into digital signals.

[0080] The averaging circuit 118 averages multiple P-axis angular velocity signals, multiple Y-axis angular velocity signals, and multiple R-axis angular velocity signals obtained over a predetermined period of time. The averaging circuit 118 outputs the averaged P-axis angular velocity signals, Y-axis angular velocity signals, and R-axis angular velocity signals to the subtractor 120 and the long-time integrator 122.

[0081] The long-time integrator 122 calculates the drift components of the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal by performing a cyclic integral of the averaged P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal, respectively. The long-time integrator 122 outputs the calculated drift components of the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal to the subtractor 120.

[0082] The subtractor 120 subtracts the drift components of the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal, calculated by the long-time integrator 122, from the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal output from the averaging circuit 118, thereby correcting the drift of the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal, respectively.

[0083] The coring circuit 124 performs coring processing (for example, noise reduction processing that reduces angular velocity signals below a certain level to zero) on the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal, which have been drift-corrected by the subtractor 120.

[0084] The integration circuit 126 integrates the P-axis angular velocity signal, Y-axis angular velocity signal, and R-axis angular velocity signal, respectively, which have been cored by the corering circuit 124, and converts them into P-axis angle signal, Y-axis angle signal, and R-axis angle signal. The P-axis angle signal is a signal indicating the rotation angle around the P-axis, the Y-axis angle signal is a signal indicating the rotation angle around the Y-axis, and the R-axis angle signal is a signal indicating the rotation angle around the R-axis. In the following explanation, for convenience, when it is not necessary to distinguish between the P-axis angle signal, Y-axis angle signal, and R-axis angle signal, they will be collectively referred to as "angle signals."

[0085] The phase compensator 128 compensates for the phase delays of the P-axis angle signal, Y-axis angle signal, and R-axis angle signal obtained by the integration circuit 126. In other words, the angle signal input to the phase compensator 128 has a delay time from when the vibration sensor 70 detects vibration of the imaging device 10 until it outputs an angular velocity signal, and a delay time required for integration processing by the integration circuit 126. The phase compensator 128 compensates for the phase delay which is the sum of the delay time in the vibration sensor 70 and the delay time in the integration circuit 126.

[0086] As described later, CPU90 operates as a low-pass filter processing unit 202. The P-axis angle signal, Y-axis angle signal, and R-axis angle signal, whose phase delay has been compensated by the phase compensator 128, are subjected to low-pass filtering by the low-pass filter processing unit 202 (described later) and then output to the multiplier 130, provided that the shutter speed of the mechanical shutter 64 meets certain conditions.

[0087] On the other hand, if the shutter speed of the mechanical shutter 64 does not meet certain conditions, the P-axis angle signal, Y-axis angle signal, and R-axis angle signal, whose phase delay has been compensated by the phase compensator 128, are output to the multiplier 130 without being subjected to low-pass filtering by the low-pass filter processing unit 202, which will be described later. The low-pass filtering in the low-pass filter processing unit 202 will be described later. The angle signal is an example of a "signal obtained in conjunction with vibration of the imaging device" related to the technology disclosed in this application.

[0088] The NVM92 stores a P-axis conversion coefficient that defines the amount of displacement of the image sensor 18 in the P-axis direction in response to a P-axis angle signal (for example, a coefficient that converts the rotation angle indicated by the P-axis angle signal to the amount of displacement of the image sensor 18 in the P-axis direction), a Y-axis conversion coefficient that defines the amount of displacement of the image sensor 18 in the Y-axis direction in response to a Y-axis angle signal (for example, a coefficient that converts the rotation angle indicated by the Y-axis angle signal to the amount of displacement of the image sensor 18 in the Y-axis direction), and an R-axis conversion coefficient that defines the amount of displacement of the image sensor 18 around the R-axis in response to an R-axis angle signal (for example, a coefficient that converts the rotation angle indicated by the R-axis angle signal to the amount of displacement of the image sensor 18 in the R-axis direction). In the following, for the sake of convenience, when it is not necessary to distinguish between the P-axis conversion coefficient, Y-axis conversion coefficient, and R-axis conversion coefficient, they will be collectively referred to as "conversion coefficients."

[0089] The multiplier 130 generates a P-axis displacement signal corresponding to the displacement of the image sensor 18 in the P-axis direction by multiplying the P-axis angle signal by the P-axis conversion coefficient stored in the NVM 92. The multiplier 130 also generates a Y-axis displacement signal corresponding to the displacement of the image sensor 18 in the Y-axis direction by multiplying the Y-axis angle signal by the Y-axis conversion coefficient stored in the NVM 92. Furthermore, the multiplier 130 generates an R-axis displacement signal corresponding to the displacement of the image sensor 18 around the R-axis by multiplying the R-axis angle signal by the R-axis conversion coefficient stored in the NVM 92.

[0090] The adder 132 generates a P-axis target position signal by adding a predetermined reference voltage to the P-axis displacement signal generated by the multiplier 130. The adder 132 also generates a Y-axis target position signal by adding a predetermined reference voltage to the Y-axis displacement signal generated by the multiplier 130. Furthermore, the adder 132 generates an R-axis target position signal by adding a predetermined reference voltage to the R-axis displacement signal generated by the multiplier 130. For the sake of clarity, in the following explanation, unless it is necessary to distinguish between the P-axis target position signal, the Y-axis target position signal, and the R-axis target position signal, these will be collectively referred to as the "target position signal."

[0091] The amplifier 136 amplifies the P-axis position detection signal, the Y-axis position detection signal, and the R-axis position detection signal output from the position sensor 100, respectively.

[0092] The A / D converter 138 converts the analog signals amplified by the amplifier 136, namely the P-axis position detection signal, the Y-axis position detection signal, and the R-axis position detection signal, into digital signals, respectively.

[0093] The current position converter 140 generates a P-axis current position signal (for example, a signal that can identify the current position of the image sensor 18 in the P-axis direction) corresponding to the current position of the image sensor 18 in the P-axis direction, based on the P-axis position detection signal converted into a digital signal by the A / D converter 138. The current position converter 140 also generates a Y-axis position detection signal (for example, a signal that can identify the current position of the image sensor 18 in the Y-axis direction), which has been converted into a digital signal by the A / D converter 138. Furthermore, the current position converter 140 generates an R-axis position detection signal (for example, a signal that can identify the current position of the image sensor 18 in the R-axis direction), which has been converted into a digital signal by the A / D converter 138. In the following, for the sake of explanation, when it is not necessary to distinguish between the P-axis current position signal, the Y-axis current position signal, and the R-axis current position signal, they will be collectively referred to as the "current position signal."

[0094] The subtractor 134 subtracts the Y-axis target position signal from the P-axis target position signal, subtracts the Y-axis current position signal from the Y-axis target position signal, and subtracts the R-axis current position signal from the R-axis target position signal.

[0095] As will be described later, the CPU 90 operates not only as the low-pass filter processing unit 202, but also as a drive control unit 204, a phase control unit 206, and a gain control unit 212.

[0096] The filter calculator 142 calculates a P-axis drive amount signal representing the drive amount in the P-axis direction, a Y-axis drive amount signal representing the drive amount in the Y-axis direction, and an R-axis drive amount signal representing the drive amount around the R-axis, based on the subtraction result by the subtractor 134 and whether or not low-pass filtering is performed by the low-pass filter processing unit 202. For the sake of explanation, in the following, unless it is necessary to distinguish between the P-axis drive amount signal, the Y-axis drive amount signal, and the R-axis drive amount signal, these will be collectively referred to as "drive amount signals."

[0097] Furthermore, the filter calculator 142 amplifies the P-axis drive amount signal, the Y-axis drive amount signal, and the R-axis drive amount signal based on the gain calculated by the gain control unit 212. The gain calculated by the gain control unit 212 is, for example, the gain of feedback control (here, as an example, PID control). Note that the amplification process based on the gain calculated by the gain control unit 212 may be performed in the filter calculator 142. Also, the gain used in the amplification process may be other than the gain of feedback control (here, as an example, PID control).

[0098] The control output calculator 144 calculates the allocation of drive amounts for the first VCM 170, second VCM 172, third VCM 174, and fourth VCM 176 (see Figure 13 for all of them), which constitute the shake correction actuator 102, based on the drive amount signals calculated by the filter calculator 142. Then, according to the allocation of drive amounts, the control output calculator 144 outputs a first control signal for the first VCM 170, a second control signal for the second VCM 172, and a third control signal for the third VCM 174 and fourth VCM 176 to the shake correction driver 76.

[0099] The first control signal is used to control the first VCM 170 by the drive amount allocated to the first VCM 170 by the control output calculator 144. The second control signal is used to control the second VCM 172 by the drive amount allocated to the second VCM 172 by the control output calculator 144. The third control signal is used to control the third VCM 174 and fourth VCM 176 by the drive amounts allocated to the third VCM 174 and fourth VCM 176 by the control output calculator 144.

[0100] The drive control unit 204 outputs a drive command to the control output calculator 144. Upon receiving the drive command from the drive control unit 204, the control output calculator 144 outputs a first control signal, a second control signal, and a third control signal to the image stabilization driver 76. The image stabilization driver 76 generates a first drive signal, a second drive signal, and a third drive signal based on the first control signal, the second control signal, and the third control signal.

[0101] The phase control unit 206 outputs a phase difference command to the control output calculator 144. Based on the phase difference command input from the phase control unit 206, the control output calculator 144 sets a first phase difference between the first control signal and the second control signal, and a second phase difference between the first control signal and the third control signal. As a result, a first phase difference is set between the first drive signal and the second drive signal output from the image stabilization driver 76, and a second phase difference is set between the first drive signal and the third drive signal. Here, an example is given in which the first and second phase differences are set according to instructions from the phase control unit 206, but the technology of this disclosure is not limited thereto. For example, assuming that the first and second phase differences are known, the image stabilization driver 76 may be equipped with a phase difference function that can operate independently of the CPU 90, and the first and second phase differences may be set by the phase difference function of the image stabilization driver 76.

[0102] The image stabilization driver 76 outputs a first drive signal, a second drive signal, and a third drive signal to the image stabilization actuator 102. For the sake of explanation, unless it is necessary to distinguish between the first drive signal, the second drive signal, and the third drive signal, these will be collectively referred to as the "drive signal." The drive signal is a signal that drives the system in a direction that makes the difference between the current position and the target position zero, and specifically, it is a voltage value.

[0103] The image blur correction actuator 102 is driven based on a drive signal. This causes the image blur correction actuator 102 to move the image sensor 18 in a direction that corrects the blur in the image captured by the image sensor 18, thereby correcting the image blur. The processing in the drive control unit 204, phase control unit 206, and gain control unit 212 will be described in detail below.

[0104] (CPU90 functionality) As an example, as shown in Figure 5, the imaging support process is realized by the CPU 90 executing the imaging support process program 180. The imaging support process program 180 is an example of a "program" related to the technology of this disclosure. In the example shown in Figure 5, the imaging support process program 180 is stored in the NVM 92, and the CPU 90 reads the imaging support process program 180 from the NVM 92 and executes it on the RAM 94.

[0105] The CPU 90 performs imaging support processing according to the imaging support processing program 180 executed on the RAM 94. By executing the imaging support processing program 180 on the RAM 94, the CPU 90 operates as a low-pass filter processing unit 202, a drive control unit 204, a phase control unit 206, a shutter mode determination unit 208, a shutter speed determination unit 210, and a gain control unit 212.

[0106] As an example, the low-pass filter processing unit 202 shown in Figure 6 performs low-pass filtering on the P-axis angle signal, Y-axis angle signal, and R-axis angle signal, whose phase delay has been compensated by the phase compensator 128 (see Figure 4), at a predetermined cutoff frequency. The cutoff frequency is stored in, for example, the NVM 92. For low-pass filtering, for example, IIR filtering is used. In imaging by the image sensor 18, the low-pass filter processing unit 202 performs low-pass filtering when the shutter speed Sp of the mechanical shutter 64 is Sp ≥ 1 / 4 second, and does not perform low-pass filtering when the shutter speed Sp of the mechanical shutter 64 is Sp < 1 / 4 second.

[0107] As an example, as shown in Figure 7, when the image stabilization mode is set according to instructions received by, for example, the receiving device 83 (see Figure 3), the drive control unit 204 outputs a drive command to the control output calculator 144. When the control output calculator 144 receives the drive command output by the drive control unit 204, it outputs a control signal to the image stabilization driver 76, and when the image stabilization driver 76 receives the control signal, it outputs a first drive signal, a second drive signal, and a third drive signal. The first drive signal, the second drive signal, and the third drive signal are, for example, PWM signals. The first drive signal, the second drive signal, and the third drive signal may also be sinusoidal signals.

[0108] The first VCM 170 is driven based on the first drive signal, the second VCM 172 is driven based on the second drive signal, and the third VCM 174 and fourth VCM 176 are driven based on the third drive signal. As a result, power is supplied to the image sensor 18 by the blur correction actuator 102, causing the image sensor 18 to move in a direction that corrects the blur of the image captured by the image sensor 18, thereby correcting the image blur. In this way, the imaging device 10 performs movement control to move the image sensor 18 in a direction that corrects the blur of the image captured by the image sensor 18, based on the vibration of the imaging device 10. Details of the configuration of the blur correction actuator 102 having the first VCM 170, second VCM 172, third VCM 174, and fourth VCM 176 will be described later.

[0109] As an example, as shown in Figure 7, the phase control unit 206 outputs a phase difference command to the control output calculator 144. Based on the phase difference command input from the phase control unit 206, the control output calculator 144 sets a first phase difference between the first control signal and the second control signal, and a second phase difference between the first control signal and the third control signal. As a result, a first phase difference ΔT1 is set between the first drive signal that drives the first VCM 170 and the second drive signal that drives the second VCM 172, and a second phase difference ΔT2 is set between the first drive signal that drives the first VCM 170 and the third drive signal that drives the third VCM 174 and the fourth VCM 176.

[0110] As an example, the first phase difference ΔT1 is 180° and the second phase difference ΔT2 is 45°. The second phase difference ΔT2 may also be 90°. Furthermore, the first phase difference ΔT1 may be other than 180°, and the second phase difference ΔT2 may be other than 45°. It is preferable that the first phase difference and the second phase difference are different. The first drive signal is an example of the "first drive signal" according to the technology of this disclosure, and the second drive signal and the third drive signal are examples of the "second drive signal" according to the technology of this disclosure.

[0111] Figure 8 shows, as an example, the operation of the CPU 90 when the system transitions from a state where a live view image is displayed to a state where exposure and image storage are performed, and then the live view image is displayed again.

[0112] In Figure 8, "Live View Image Display" means the state in which the live view image is displayed on the display 28, "S1 Pressed" means the state in which the release button 20 is half-pressed, "AE" means that automatic exposure is being performed, "AF" means that automatic focus is being performed, "Front Curtain Drive" means that the front curtain 64A is open, "Exposure" means that image capture is being performed by the image sensor 18, "Rear Curtain Drive" means that the rear curtain 64B is closed, and "Image Storage" means that the captured image is stored in the image memory 80.

[0113] Furthermore, in Figure 8, the first mode is the operating mode of the CPU 90 that displays the live view image on the display 28 until the release button 20 is half-pressed; the second mode is the operating mode of the CPU 90 that performs automatic exposure and autofocus from the time the release button 20 is half-pressed until the release button 20 is fully pressed; and the third mode is the operating mode of the CPU 90 that performs exposure and storage of the captured image from the time the release button 20 is fully pressed until the captured image is stored.

[0114] The drive control unit 204 specifies the frequency of the drive signal to the control output calculator 144 via a drive command, and controls the shake correction driver 76 to change the frequency of the drive signal output from the shake correction driver 76 to the shake correction actuator 102.

[0115] Specifically, when the CPU 90 is operating in the first mode, the drive control unit 204 controls the image stabilization driver 76 to drive the image stabilization actuator 102 with a drive signal of the first frequency F1. When the CPU 90 is operating in the second mode, the drive control unit 204 controls the image stabilization driver 76 to drive the image stabilization actuator 102 with a drive signal of the second frequency F2. When the CPU 90 is operating in the third mode, the drive control unit 204 controls the image stabilization driver 76 to drive the image stabilization actuator 102 with a drive signal of the third frequency.

[0116] For example, the first frequency F1 is 100 Hz, the second frequency F2 is 200 Hz, and the third frequency F3 is 400 Hz. However, the first frequency F1 may be other than 100 Hz, the second frequency F2 may be other than 200 Hz, and the third frequency F3 may be other than 400 Hz. The first frequency F1 and the second frequency F2 are examples of the "first frequency" relating to the technology of this disclosure, and the third frequency F3 is an example of the "second frequency" relating to the technology of this disclosure.

[0117] Figure 9 shows, as an example, the operation of the CPU 90 when transitioning from a state where a live view image is displayed to a state where continuous imaging is performed by the image sensor 18 in electronic front curtain shutter mode. In Figure 9, "electronic front curtain operation" refers to the state in which the front curtain 64A remains open and the electronic shutter operates as an electronic front curtain, and "continuous imaging" refers to the process in which multiple frames of images are obtained by imaging performed by the image sensor 18, and these multiple frames of images are sequentially stored in the image memory 80. Examples of "continuous imaging" include so-called burst shooting or imaging for recording video.

[0118] Furthermore, in Figure 9, the fourth mode is the operating mode of the CPU 90 that enables continuous imaging. When the CPU 90 is in the fourth mode, the drive control unit 204 controls the image stabilization driver 76 to drive the image stabilization actuator 102 with a drive signal of the third frequency F3.

[0119] As an example, as shown in Figure 10, the shutter mode determination unit 208 determines the shutter mode. Specifically, the shutter mode determination unit 208 determines that the operating mode of the CPU 90 is the electronic shutter mode if it is the first mode or the second mode. The electronic shutter mode is the operating mode in which the electronic shutter is activated.

[0120] Furthermore, the shutter mode determination unit 208 determines that the operating mode of the CPU 90 is the mechanical shutter mode if it is the third mode. The mechanical shutter mode is an operating mode in which the front curtain 64A of the mechanical shutter 64 is driven first, followed by the rear curtain 64B. The time interval from the start of driving the front curtain 64A to the start of driving the rear curtain 64B when one frame is captured is determined, for example, according to the imaging conditions (e.g., exposure amount) specified by the user.

[0121] Furthermore, the shutter mode determination unit 208 determines that the operating mode of the CPU 90 is the fourth mode, and that it is the electronic front curtain shutter mode. The electronic front curtain shutter mode is an operating mode in which the electronic shutter is operated as the electronic front curtain, and then the rear curtain 64B of the mechanical shutter 64 is driven. The time interval from the start of operation of the electronic front curtain to the start of driving of the rear curtain 64B when one frame is captured is determined, for example, according to the imaging conditions (e.g., exposure amount) specified by the user.

[0122] The shutter speed determination unit 210 shown in Figure 8 determines the shutter speed in mechanical shutter mode. In mechanical shutter mode, the shutter speed corresponds to the time from when the front curtain 64A opens until the rear curtain 64B closes.

[0123] The gain control unit 212 controls the gain that amplifies the control signal. Increasing the gain improves the response performance of the image sensor 18's movement control. More specifically, it increases the response speed when the image sensor 18 moves from its current position to the target position. This increases the energy that holds the image sensor 18 on the optical axis OA. In order to ensure vibration damping performance during exposure, the gain control unit 212 increases the gain in the third and fourth exposure modes compared to the first and second modes.

[0124] In other words, in the first and second modes, the gain is set to the first gain G1; in the third mode, the gain is set to the second gain G2 or the third gain G3; and in the fourth mode, the gain is set to the second gain G2. The second gain G2 is higher than the first gain G1, and the third gain G3 is higher than the second gain G2. The first gain G1, the second gain G2, and the third gain G3 may each be a gain value, or they may be a gain width having a certain range.

[0125] Hereafter, control that sets the gain to the first gain G1 or the second gain G2 will be referred to as normal gain control, and control that raises the gain to the third gain G3, which is higher than the second gain G2, will be referred to as gain-up control. The second gain G2 is set to the optimal value for suppressing image blur caused by camera shake, and the third gain G3 is set to the optimal value for suppressing image blur caused by vibration of the mechanical shutter 64.

[0126] Incidentally, the camera shake vibrations acting on the imaging device 10 are generally vibrations with a frequency of about 1 Hz to 20 Hz. The mechanical shutter 64 is positioned adjacent to the image sensor 18, and when the mechanical shutter 64 is driven in mechanical shutter mode, vibrations of the mechanical shutter 64 may be transmitted to the image sensor 18. The vibrations of the mechanical shutter 64 are generally vibrations with a frequency of 30 Hz to 100 Hz, which are higher frequency vibrations than camera shake vibrations. If the gain is kept at the second gain G2 in the third mode, when vibrations of the mechanical shutter 64 are transmitted to the image sensor 18, the image sensor 18 may move, potentially causing image blur.

[0127] Therefore, in order to suppress image blur caused by vibrations of the mechanical shutter 64, it is conceivable to uniformly raise the gain to the third gain G3 in the third mode. However, raising the gain increases the gain across the entire frequency band. For this reason, if the shake correction actuator 102 is driven to suppress image blur caused by hand shake while the gain is raised to the third gain G3, the volume of the drive sound will increase, generating noise that may cause discomfort to the user. Therefore, it is desirable to be able to achieve both the suppression of image blur caused by vibrations of the mechanical shutter 64 and the suppression of discomfort to the user.

[0128] Figure 11 shows the measurement results regarding the relationship between shutter speed and resolution degradation rate for both mechanical shutter mode and electronic front curtain shutter mode. The measurement results shown in Figure 11 are data when the gain is set to the second gain G2.

[0129] The resolution degradation rate refers to the ratio indicating the degree of resolution degradation due to blur. As an example of the resolution degradation rate, the ratio of the number of all pixel lines (for example, pixel lines in the column direction and / or row direction) forming the first pixel region facing the shutter frame among the imaging surfaces of the image sensor 18 to the number of all pixel lines forming the second pixel region affected by shake in the first pixel region can be cited. Here, the number of pixel lines is exemplified, but it is not limited to this, and it may be the number of pixels, the area, or the number of charts expressing a group of a plurality of pixel lines in a plurality of stages in the row direction or column direction, etc.

[0130] As an example, as shown in FIG. 11, in the case of the electronic front curtain shutter mode, even if the shutter speed Sp changes, the resolution degradation rate is generally low. In the case of the mechanical shutter mode, when the shutter speed Sp satisfies Sp≧1 / 4 second or Sp≦1 / 60 second, the resolution degradation rate becomes low and the image quality of the captured image can be ensured. On the other hand, in the case of the mechanical shutter mode, when the shutter speed Sp satisfies 1 / 60 second < Sp < 1 / 4 second, due to the influence of image blur accompanying the vibration of the mechanical shutter 64, the resolution degradation rate becomes high and the image quality of the captured image deteriorates. Also, in the case of the mechanical shutter mode, when the shutter speed Sp satisfies 1 / 30 second < Sp < 1 / 8 second, due to the influence of image blur accompanying the vibration of the mechanical shutter 64, the resolution degradation rate becomes even higher and the image quality of the captured image deteriorates further.

[0131] Therefore, the gain control unit 212 performs control to set the gain as follows so as to achieve both suppression of image blur accompanying the vibration of the mechanical shutter 64 and suppression of discomfort given to the user.

[0132] That is, as an example, as shown in FIGS. 8 and 11, when the shutter speed Sp in the mechanical shutter mode (i.e., the third mode) is such that 1 / 60 second < Sp < 1 / 4 second, the gain control unit 212 performs gain-up control to increase the gain to a third gain G3 that is higher than the second gain G2. On the other hand, when the shutter speed Sp in the mechanical shutter mode is such that Sp ≥ 1 / 4 second or Sp ≤ 1 / 60 second, the gain control unit 212 performs normal gain control to set the gain to the second gain G2.

[0133] 1 / 4 second is an example of the "first predetermined time" according to the technology of the present disclosure, and 1 / 60 second is an example of the "second predetermined time" according to the technology of the present disclosure.

[0134] Incidentally, as an example, as shown in FIG. 9, when continuous imaging by the image sensor 18 is performed in the electronic front curtain shutter mode (i.e., in the case of the fourth mode), the gain control unit 212 performs normal gain control to set the gain to the second gain G2.

[0135] Also, as an example, as shown in FIGS. 8 and 9, in the case of the electronic shutter mode (i.e., the first mode or the second mode), the gain control unit 212 performs normal gain control to set the gain to the first gain G1.

[0136] (Gain Control Process) Next, a process for controlling the gain in the imaging device 10 (hereinafter referred to as the gain control process) will be described with reference to FIG. 12.

[0137] In the gain control process shown in Figure 12, first, in step ST102, the shutter mode determination unit 208 (see Figure 5) determines the shutter mode. For example, if the operating mode of the CPU 90 is the first mode or the second mode (see Figures 8 and 9), the shutter mode is the electronic shutter mode, so the gain control process proceeds to step ST104. Also, if the operating mode of the CPU 90 is the fourth mode (see Figure 9), the shutter mode is the electronic front curtain shutter mode, so the gain control process proceeds to step ST104.

[0138] In step ST104, the gain control unit 212 performs normal gain control. Specifically, if the operating mode of the CPU 90 is the first mode or the second mode (see Figures 8 and 9), and the shutter mode is the electronic shutter mode, the gain control unit 212 controls the gain to the first gain G1. Also, if the operating mode of the CPU 90 is the fourth mode (see Figure 9), and the shutter mode is the electronic front curtain shutter mode, and continuous imaging is performed by the image sensor 18, the gain control unit 212 controls the gain to the second gain G2.

[0139] On the other hand, if the operating mode of the CPU 90 in step ST102 described above is the third mode (see Figure 8), the shutter mode is the mechanical shutter mode, so the gain control process proceeds to step ST106.

[0140] In step ST106, the shutter speed determination unit 210 (see Figure 5) determines the shutter speed Sp. If the shutter speed Sp is Sp ≥ 1 / 4 second or Sp ≤ 1 / 60 second, the gain control process proceeds to step ST108.

[0141] In step ST108, the gain control unit 212 performs normal gain control. That is, when the operation mode of the CPU 90 is the third mode (see FIG. 8), the shutter mode is the mechanical shutter mode, and the shutter speed Sp satisfies Sp ≧ 1 / 4 second or Sp ≦ 1 / 60 second, the gain control unit 212 performs control to set the gain to the second gain G2.

[0142] On the other hand, in step ST106 described above, when the shutter speed Sp satisfies 1 / 60 second < Sp < 1 / 4 second, the gain control process proceeds to step ST110.

[0143] In step ST110, the gain control unit 212 performs gain-up control. That is, when the operation mode of the CPU 90 is the third mode (see FIG. 8), the shutter mode is the mechanical shutter mode, and the shutter speed Sp satisfies 1 / 60 second < Sp < 1 / 4 second, the gain control unit 212 performs control to set the gain to the third gain G3.

[0144] Note that the gain control process in the imaging device 10 described above is an example of the "operation method of the imaging device 10" according to the technology of the present disclosure.

[0145] (Shake correction mechanism 72) Next, an example of the shake correction mechanism 72 applied to the imaging device 10 will be described with reference to FIGS. 13 to 16.

[0146] As an example, as shown in Figures 13 to 16, the image stabilization mechanism 72 comprises a movable member 150, a first fixed member 152, and a second fixed member 154. The first fixed member 152 is positioned opposite the movable member 150 in the R-axis direction, and the second fixed member 154 is positioned on the opposite side of the movable member 150 from the first fixed member 152 in the R-axis direction. The first fixed member 152 and the second fixed member 154 are fixed to a fixed part 156 provided on the imaging device body 12 (for example, a frame forming the housing of the imaging device body 12). The movable member 150 is supported by the first fixed member 152 and the second fixed member 154 so as to be movable in the P-axis direction and the Y-axis direction and rotatable around the R-axis.

[0147] Multiple tension springs 158 are provided between the first fixed member 152 and the movable member 150. When the movable member 150 is not powered by the vibration correction actuator 102 (described later), the tensile force of the multiple tension springs 158 holds the movable member 150 in a predetermined reference position.

[0148] The image stabilization mechanism 72 includes a position sensor 100, as described below. The position sensor 100 comprises a first position sensor 160, a second position sensor 162, and a third position sensor 164. The first position sensor 160 has a first Hall element 160A and a first sensor magnet 160B that face each other in the R-axis direction. The second position sensor 162 has a second Hall element 162A and a second sensor magnet 162B that face each other in the R-axis direction. The third position sensor 164 has a third Hall element 164A and a third sensor magnet 164B that face each other in the R-axis direction.

[0149] The second position sensor 162 and the third position sensor 164 are positioned apart from each other in the P-axis direction. For example, the first Hall element 160A, the second Hall element 162A, and the third Hall element 164A are fixed to the movable member 150, and the first sensor magnet 160B, the second sensor magnet 162B, and the third sensor magnet 164B are fixed to the first fixed member 152. The north and south poles of the first sensor magnet 160B are aligned in the P-axis direction, the north and south poles of the second sensor magnet 162B are aligned in the Y-axis direction, and the north and south poles of the third sensor magnet 164B are aligned in the Y-axis direction. The north and south poles of the second sensor magnet 162B are positioned in the opposite direction to the north and south poles of the third sensor magnet 164B.

[0150] When the position of the movable member 150 changes to the positive or negative side in the P-axis direction relative to the first fixed member 152 and the second fixed member 154, the magnetic field acting from the first sensor magnet 160B to the first Hall element 160A changes according to the P-axis position of the movable member 150. The first Hall element 160A outputs a P-axis position detection signal (see Figure 4) corresponding to the P-axis position of the movable member 150.

[0151] When the position of the movable member 150 changes to the positive or negative side in the Y-axis direction relative to the first fixed member 152 and the second fixed member 154, the magnetic field acting from the second sensor magnet 162B to the second Hall element 162A changes according to the Y-axis position of the movable member 150. The second Hall element 162A outputs a position detection signal corresponding to the Y-axis position of the movable member 150. Similarly, when the position of the movable member 150 changes to the positive or negative side in the Y-axis direction relative to the first fixed member 152 and the second fixed member 154, the magnetic field acting from the third sensor magnet 164B to the third Hall element 164A changes according to the Y-axis position of the movable member 150. The third Hall element 164A outputs a position detection signal corresponding to the Y-axis position of the movable member 150.

[0152] When the position of the movable member 150 changes to the positive or negative side in the Y-axis direction, a position detection signal having the same phase and amplitude as the position detection signal output from the second Hall element 162A is output from the third Hall element 164A. For example, a first output circuit (not shown) is connected to the position sensor 100, and the first output circuit outputs an averaged signal, which is an average of the position detection signal output from the second Hall element 162A and the position detection signal output from the third Hall element 164A, as a Y-axis position detection signal (see Figure 4) corresponding to the Y-axis position of the movable member 150.

[0153] When the position of the movable member 150 changes to the positive or negative side around the R axis relative to the first fixed member 152 and the second fixed member 154, the magnetic field acting from the second sensor magnet 162B to the second Hall element 162A changes according to the position of the movable member 150 around the R axis. The second Hall element 162A outputs a position detection signal corresponding to the position of the movable member 150 around the R axis. Similarly, when the position of the movable member 150 changes to the positive or negative side around the R axis relative to the first fixed member 152 and the second fixed member 154, the magnetic field acting from the third sensor magnet 164B to the third Hall element 164A changes according to the position of the movable member 150 around the R axis. The third Hall element 164A outputs a position detection signal corresponding to the position of the movable member 150 around the R axis.

[0154] When the position of the movable member 150 changes to the positive or negative side around the R axis, the position detection signal output from the second Hall element 162A is inverted from the position detection signal output from the third Hall element 164A. For example, a second output circuit (not shown) is connected to the position sensor 100. The second output circuit outputs a difference signal indicating the difference between the position detection signal output from the second Hall element 162A and the position detection signal output from the third Hall element 164A as an R-axis position detection signal (see Figure 4) corresponding to the position of the movable member 150 around the R axis.

[0155] The image stabilization mechanism 72 includes an image stabilization actuator 102, as described below. The image stabilization actuator 102 comprises a first VCM 170, a second VCM 172, a third VCM 174, and a fourth VCM 176. The first VCM 170 and the second VCM 172 are arranged side by side in the Y-axis direction. The third VCM 174 and the fourth VCM 176 are arranged side by side in the P-axis direction.

[0156] The first VCM 170 has a first coil 170A and a pair of first motor magnets 170B and 170C. The second VCM 172 has a second coil 172A and a pair of second motor magnets 172B and 172C. The third VCM 174 has a third coil 174A and a pair of third motor magnets 174B and 174C. The fourth VCM 176 has a fourth coil 176A and a pair of fourth motor magnets 176B and 176C.

[0157] For example, the first coil 170A, the second coil 172A, the third coil 174A, and the fourth coil 176A are fixed to the movable member 150. The first motor magnet 170B, the second motor magnet 172B, the third motor magnet 174B, and the fourth motor magnet 176B are fixed to the first fixed member 152. The first motor magnet 170C, the second motor magnet 172C, the third motor magnet 174C, and the fourth motor magnet 176C are fixed to the second fixed member 154.

[0158] The north and south poles of the first motor magnet 170B are aligned in the P-axis direction. The north and south poles of the second motor magnet 172B are aligned in the P-axis direction. The north and south poles of the third motor magnet 174B are aligned in the Y-axis direction. The north and south poles of the fourth motor magnet 176B are aligned in the Y-axis direction.

[0159] Similarly, the north and south poles of the first motor magnet 170C are aligned in the P-axis direction. The north and south poles of the second motor magnet 172C are aligned in the P-axis direction. The north and south poles of the third motor magnet 174C are aligned in the Y-axis direction. The north and south poles of the fourth motor magnet 176C are aligned in the Y-axis direction.

[0160] The first coil 170A and the second coil 172A are independently connected to the image stabilization driver 76 (see Figures 3 and 4). On the other hand, the third coil 174A and the fourth coil 176A are connected in parallel to the image stabilization driver 76 (see Figures 3 and 4).

[0161] The winding direction of the first coil 170A is the same as the winding direction of the second coil 172A, and the north and south poles of the first motor magnet 170B are positioned in the same direction as the north and south poles of the second motor magnet 172B. Furthermore, the north and south poles of the first motor magnet 170C are positioned in the same direction as the north and south poles of the first motor magnet 170B, and the north and south poles of the second motor magnet 172C are also positioned in the same direction as the north and south poles of the second motor magnet 172B.

[0162] On the other hand, the winding direction of the third coil 174A is opposite to that of the fourth coil 176A, and the north and south poles of the third motor magnet 174B are positioned opposite to those of the fourth motor magnet 176B. The north and south poles of the third motor magnet 174C are positioned in the same direction as those of the third motor magnet 174B, and the north and south poles of the fourth motor magnet 176C are also positioned in the same direction as those of the fourth motor magnet 176B.

[0163] The first coil 170A is supplied with a first drive signal (see Figure 4) from the image stabilization driver 76, and the second coil 172A is supplied with a second drive signal (see Figure 4) from the image stabilization driver 76. When the first drive signal is supplied to the first coil 170A, current flows through the first coil 170A, and when the second drive signal is supplied to the second coil 172A, current flows through the second coil 172A.

[0164] When current flows in the same direction through the first coil 170A and the second coil 172A, a first force P1 (see Figure 14) in the P-axis direction is generated between the first coil 170A and the pair of first motor magnets 170B and 170C, and a second force P2 (see Figure 14) in the same direction as the first force P1 is generated between the second coil 172A and the pair of second motor magnets 172B and 172C, causing the movable member 150 to move in the P-axis direction. Depending on the direction of the current flowing through the first coil 170A and the second coil 172A, the directions of the first force P1 and the second force P2 are switched, and the movable member 150 moves to the + side or - side in the P-axis direction. When the movable member 150 moves to the + side or - side in the P-axis direction, the image sensor 18 moves to the + side or - side in the P-axis direction together with the movable member 150.

[0165] When current flows in the opposite direction through the first coil 170A and the second coil 172A, the first power P1 generated between the first coil 170A and the pair of first motor magnets 170B and 170C, and the second power P2 generated between the second coil 172A and the pair of second motor magnets 172B and 172C, are reversed in direction, causing the movable member 150 to rotate around the R axis. Depending on the direction of the current flowing through the first coil 170A and the second coil 172A, the directions of the first power P1 and the second power P2 are switched, and the movable member 150 rotates to the + side or the - side around the R axis. When the movable member 150 rotates to the + side or the - side around the R axis, the image sensor 18 rotates to the + side or the - side around the R axis together with the movable member 150.

[0166] The third coil 174A and the fourth coil 176A are supplied with a third drive signal (see Figure 4) from the shake correction driver 76. When the third drive signal is supplied to the third coil 174A and the fourth coil 176A, current flows through the third coil 174A and the second coil 172A.

[0167] When current is supplied to the third coil 174A and the fourth coil 176A, a third force P3 in the Y-axis direction is generated between the third coil 174A and the pair of third motor magnets 174B and 174C, and a fourth force P4 in the same direction as the third force P3 is generated between the fourth coil 176A and the pair of fourth motor magnets 176B and 176C, causing the movable member 150 to move in the Y-axis direction. Depending on the direction of the current flowing through the third coil 174A and the fourth coil 176A, the directions of the third force P3 and the fourth force P4 are switched, and the movable member 150 moves to the + side or - side in the Y-axis direction. When the movable member 150 moves to the + side or - side in the Y-axis direction, the image sensor 18 moves to the + side or - side in the Y-axis direction together with the movable member 150.

[0168] As an example, as shown in Figure 14, the movable member 150 has a first support portion 171 that supports the first coil 170A, a second support portion 173 that supports the second coil 172A, a third support portion 175 that supports the third coil 174A, and a fourth support portion 177 that supports the fourth coil 176A.

[0169] The first support portion 171 is formed in a generally C-shape with a first notch 171A that opens on the + side in the P-axis direction, and the first coil 170A is positioned inside the first support portion 171. The second support portion 173 is formed in a generally C-shape with a second notch 173A that opens on the + side in the P-axis direction, and the second coil 172A is positioned inside the second support portion 173.

[0170] The third support portion 175 is formed in a generally C-shape with a third notch 175A that opens to the negative side in the Y-axis direction, and the third coil 174A is positioned inside the third support portion 175. The fourth support portion 177 is formed in a generally C-shape with a fourth notch 177A that opens to the negative side in the Y-axis direction, and the fourth coil 176A is positioned inside the fourth support portion 177.

[0171] Since the first support portion 171 and the second support portion 173 are both formed in a roughly C-shape that opens to the + side in the P-axis direction, the movable member 150 is made smaller in the P-axis direction compared to, for example, the case where the first support portion 171 and the second support portion 173 are formed in annular shapes that surround the first coil 170A and the second coil 172A, respectively. Similarly, since the third support portion 175 and the fourth support portion 177 are both formed in a roughly C-shape that opens to the - side in the Y-axis direction, the movable member 150 is made smaller in the Y-axis direction compared to, for example, the case where the third support portion 175 and the fourth support portion 177 are formed in annular shapes that surround the third coil 174A and the fourth coil 176A, respectively.

[0172] Furthermore, if the first support portion 171 and the second support portion 173 have first notches 171A and 2 notches 173A that open to the + side in the P-axis direction, there is a risk that the magnetic fields of the first coil 170A and the second coil 172A will be emitted through the first notches 171A and 2 notches 173A. Similarly, if the third support portion 175 and the fourth support portion 177 have third notches 175A and 4 notches 177A that open to the - side in the Y-axis direction, there is a risk that the magnetic fields of the third coil 174A and the fourth coil 176A will be emitted through the third notches 175A and 4 notches 177A. When magnetic fields are emitted from the first coil 170A, the second coil 172A, the third coil 174A, and the fourth coil 176A, there is a risk that the image sensor 18 will be affected by electromagnetic noise.

[0173] Therefore, as a first measure to suppress the image sensor 18 from being affected by electromagnetic noise, as described above, the phase control unit 206 shown in Figure 7 provides a first phase difference ΔT1 between the first drive signal and the second drive signal, and a second phase difference ΔT2 between the first drive signal and the third drive signal. When a first phase difference ΔT1 is provided between the first drive signal and the second drive signal, and a second phase difference ΔT2 is provided between the first drive signal and the third drive signal, the generation of electromagnetic noise from the first coil 170A, the second coil 172A, the third coil 174A, and the fourth coil 176A due to the rising and falling edges of the first drive signal, the second drive signal, and the third drive vibration is suppressed compared to the case where there is no first phase difference ΔT1 and the second phase difference ΔT2.

[0174] Furthermore, as a second measure to suppress the image sensor 18 from being affected by electromagnetic noise, as described above, the winding direction of the third coil 174A is set to be opposite to the winding direction of the fourth coil 176A. As an example, as shown in Figure 17, when the winding direction of the third coil 174A is opposite to that of the fourth coil 176A, the direction of the current I3 flowing through the third coil 174A and the direction of the current I4 flowing through the fourth coil 176A are opposite, and the direction of the magnetic flux M3 emitted from the third coil 174A and the direction of the magnetic flux M4 emitted from the fourth coil 176A are also opposite. Therefore, the magnetic flux M3 emitted from the third coil 174A and the magnetic flux M4 emitted from the fourth coil 176A cancel each other out, so the generation of electromagnetic noise from the third coil 174A and the fourth coil 176A is suppressed.

[0175] As described above, the north and south poles of the third motor magnet 174B are positioned in opposite directions to the north and south poles of the fourth motor magnet 176B. Similarly, the north and south poles of the third motor magnet 174C are positioned in opposite directions to the north and south poles of the fourth motor magnet 176C. Therefore, even if the winding direction of the third coil 174A is opposite to the winding direction of the fourth coil 176A, the direction of the third power P3 generated by the third VCM 174 and the direction of the fourth power P4 generated by the fourth VCM 176, as shown in Figure 14, can be aligned.

[0176] As a third measure for suppressing the influence of electromagnetic noise on the image sensor 18, a measure may be taken to cover the first coil 170A, the second coil 172A, the third coil 174A, and the fourth coil 176A with a member having electromagnetic shielding properties such as a copper sheet or the like.

[0177] The first VCM 170 is an example of the "first actuator" according to the technology of the present disclosure, and the second VCM 172, the third VCM 174, and the fourth VCM 176 are examples of the "second actuator" according to the technology of the present disclosure. Further, the third VCM 174 is an example of the "first voice coil motor" according to the technology of the present disclosure, and the fourth VCM 176 is an example of the "second voice coil motor" according to the technology of the present disclosure. The third coil 174A of the third VCM 174 is an example of the "first coil" according to the technology of the present disclosure, and the third motor magnets 174B and 174C of the third VCM 174 are examples of the "first magnet" according to the technology of the present disclosure. Also, the fourth coil 176A of the fourth VCM 176 is an example of the "second coil" according to the technology of the present disclosure, and the fourth motor magnets 176B and 176C of the fourth VCM 176 are examples of the "second magnet" according to the technology of the present disclosure.

[0178] (Effect) Next, the effects of the imaging device 10 will be described.

[0179] As described in detail above, in the imaging device 10, in imaging by the image sensor 18, when the shutter speed Sp of the mechanical shutter 64 is 1 / 60 second < Sp < 1 / 4 second, the CPU 90 performs gain-up control to increase the gain as compared with the case where the shutter speed Sp of the mechanical shutter 64 is Sp ≥ 1 / 4 second or Sp ≤ 1 / 60 second. Therefore, when the shutter speed Sp of the mechanical shutter 64 is 1 / 60 second < Sp < / 4 second, blurring of the image due to vibration of the mechanical shutter 64 can be suppressed.

[0180] That is, as shown in FIG. 11, when the shutter speed Sp of the mechanical shutter 64 is 1 / 60 second < Sp < 1 / 4 second and normal gain control is performed without gain-up control, due to the influence of image blur caused by the vibration of the mechanical shutter 64, the resolution degradation rate increases and the image quality of the captured image deteriorates. In contrast, in the imaging device 10 according to the present embodiment, when the shutter speed Sp of the mechanical shutter 64 is 1 / 60 second < Sp < 1 / 4 second, gain-up control is performed, so the influence of image blur caused by the vibration of the mechanical shutter 64 can be suppressed. Thereby, the resolution degradation rate is reduced and the image quality of the captured image can be ensured.

[0181] Also, in other words, in the imaging device 10, in imaging by the image sensor 18, when the shutter speed Sp of the mechanical shutter 64 is Sp ≧ 1 / 4 second or Sp ≦ 1 / 60 second, the gain is suppressed lower than when the shutter speed Sp of the mechanical shutter 64 is 1 / 60 second < Sp < 1 / 4 second. Therefore, when the shutter speed Sp of the mechanical shutter 64 is Sp ≧ 1 / 4 second or Sp ≦ 1 / 60 second, by suppressing the volume of the driving sound of the shake correction actuator 102, the discomfort given to the user can be suppressed.

[0182] Also, the CPU 90 performs the above-described gain-up control in the mechanical shutter mode in which the rear curtain 64B of the mechanical shutter 64 is driven after the front curtain 64A of the mechanical shutter 64 is driven. Therefore, in the mechanical shutter mode, it is possible to suppress the vibration transmitted from the driving of the mechanical shutter 64 to the image sensor 18.

[0183] Furthermore, in the electronic shutter mode, when the electronic shutter is activated, the CPU 90 controls the movement control gain, which moves the image sensor 18 in the direction that corrects image blur, to a gain lower than the gain set by the gain-up control. In other words, as an example, in the electronic shutter mode, the CPU 90 controls the gain to set the first gain G1 to be lower than the third gain G3. Therefore, in the electronic shutter mode, the volume of the drive sound of the blur correction actuator 102 can be kept low, thereby reducing discomfort to the user.

[0184] Similarly, in the electronic front curtain shutter mode, where the electronic shutter is operated as the electronic front curtain before driving the rear curtain 64B of the mechanical shutter 64, the CPU 90 controls the gain of the movement control that moves the image sensor 18 in the direction in which image blur is corrected, to a gain lower than the gain set by the gain-up control. In other words, as an example, in the electronic front curtain shutter mode, the CPU 90 controls the gain to be set to the second gain G2, which is lower than the third gain G3. Therefore, in the electronic front curtain shutter mode, the volume of the drive sound of the blur correction actuator 102 can be kept low, thereby reducing discomfort to the user.

[0185] Furthermore, when the image sensor 18 is capturing an image, if the shutter speed Sp of the mechanical shutter 64 is Sp ≥ 1 / 4 second, the CPU 90 performs a low-pass filter on the angle signal obtained due to the vibration of the imaging device 10 at a predetermined cutoff frequency, and then performs movement control to move the image sensor 18 in the direction in which image blur is corrected based on the low-pass filtered angle signal. Therefore, when the shutter speed Sp of the mechanical shutter 64 is Sp ≥ 1 / 4 second, the volume of the drive sound of the blur correction actuator 102 can be kept low due to the low-pass filter processing.

[0186] Furthermore, the CPU 90 performs the gain-up control described above when the frequency of the drive signal is a third frequency F3 that is higher than the first frequency F1 and the second frequency F2, that is, when the CPU 90 is in the third mode. Therefore, when the CPU 90 is in the third mode, it is possible to suppress both image blur caused by vibration of the mechanical shutter 64 and the discomfort caused to the user.

[0187] Furthermore, the CPU 90 provides a first phase difference ΔT1 between the first drive signal that drives the first VCM 170 and the second drive signal that drives the second VCM 172, and a second phase difference ΔT2 between the first drive signal that drives the first VCM 170 and the third drive signal that drives the third VCM 174 and fourth VCM 176. Therefore, compared to the case without the first phase difference ΔT1 and the second phase difference ΔT2, the electromagnetic noise generated from the first coil 170A, the second coil 172A, the third coil 174A, and the fourth coil 176A due to the rising and falling edges of the first drive signal, the second drive signal, and the third drive vibration can be reduced.

[0188] Furthermore, the winding direction of the third coil 174A is opposite to that of the fourth coil 176A. Therefore, the magnetic flux M3 emitted from the third coil 174A and the magnetic flux M4 emitted from the fourth coil 176A cancel each other out, thus suppressing the generation of electromagnetic noise from the third coil 174A and the fourth coil 176A.

[0189] Furthermore, the north and south poles of the third motor magnet 174B are positioned in opposite directions to the north and south poles of the fourth motor magnet 176B. Similarly, the north and south poles of the third motor magnet 174C are positioned in opposite directions to the north and south poles of the fourth motor magnet 176C. Therefore, even if the winding direction of the third coil 174A is opposite to the winding direction of the fourth coil 176A, the direction of the third power P3 generated by the third VCM 174 and the direction of the fourth power P4 generated by the fourth VCM 176 can be aligned.

[0190] (modified version) Next, a modified example of the imaging device 10 will be described.

[0191] In the above embodiment, when the shutter speed Sp in the mechanical shutter mode satisfies 1 / 60 second < Sp < 1 / 4 second, the CPU 90 performs gain-up control to increase the gain to the third gain G3. When the shutter speed Sp in the mechanical shutter mode satisfies Sp ≥ 1 / 4 second or Sp ≤ 1 / 60 second, the CPU 90 performs normal gain control to set the gain to the second gain G2.

[0192] However, when the shutter speed Sp in the mechanical shutter mode satisfies 1 / 30 second < Sp < 1 / 8 second, the CPU 90 may perform gain-up control to increase the gain to the third gain G3. When the shutter speed Sp in the mechanical shutter mode satisfies Sp ≥ 1 / 8 second or Sp ≤ 1 / 30 second, the CPU 90 may perform normal gain control to set the gain to the second gain G2. In this case, when the shutter speed Sp of the mechanical shutter 64 satisfies 1 / 30 second < Sp < 1 / 8 second, blurring of the image due to vibration of the mechanical shutter 64 can be suppressed.

[0193] That is, as an example shown in FIG. 11, in the case of the mechanical shutter mode, when the shutter speed Sp satisfies 1 / 30 second < Sp < 1 / 8 second, compared with the case where the shutter speed Sp satisfies 1 / 60 second < Sp < 1 / 4 second, due to the influence of image blurring caused by vibration of the mechanical shutter 64, the resolution degradation rate becomes higher and the image quality of the captured image further deteriorates. On the contrary, when the shutter speed Sp of the mechanical shutter 64 satisfies 1 / 30 second < Sp < 1 / 8 second, if gain-up control is performed, the influence of image blurring caused by vibration of the mechanical shutter 64 can be more effectively suppressed. Thereby, the resolution degradation rate is reduced and the image quality of the captured image can be ensured.

[0194] Furthermore, in the above explanation, the first default time, which is the lower limit threshold for whether or not to perform gain-up control, is set to 1 / 4 second or 1 / 8 second as an example, based on the measurement results shown in Figure 11. However, if, for example, other measurement results other than those shown in Figure 11 are obtained, the first default time may be set to a time other than 1 / 4 second or 1 / 8 second based on the other measurement results.

[0195] Similarly, in the above explanation, the second default time, which is the upper limit threshold for whether or not to perform gain-up control, is set to 1 / 60 second or 1 / 30 second as an example, based on the measurement results shown in Figure 11. However, if, for example, other measurement results other than those shown in Figure 11 are obtained, the second default time may be set to a time other than 1 / 60 second or 1 / 30 second based on the other measurement results.

[0196] Furthermore, in the above embodiment, the CPU 90 performs normal gain control without performing gain-up control when the shutter speed Sp in mechanical shutter mode is the first predetermined time. However, if, for example, the above-mentioned other measurement results are obtained, the CPU 90 may or may not perform gain-up control when the shutter speed Sp in mechanical shutter mode is the first predetermined time. Similarly, if, for example, the above-mentioned other measurement results are obtained, the CPU 90 may or may not perform gain-up control when the shutter speed Sp in mechanical shutter mode is the second predetermined time.

[0197] Furthermore, in the above embodiment, when the image sensor 18 is capturing an image, the CPU 90 performs low-pass filtering if the shutter speed Sp of the mechanical shutter 64 is Sp ≥ 1 / 4 second, and does not perform low-pass filtering if the shutter speed Sp of the mechanical shutter 64 is Sp < 1 / 4 second.

[0198] However, when the image sensor 18 captures an image, the CPU 90 performs low-pass filtering if the shutter speed Sp of the mechanical shutter 64 is Sp ≥ 1 / 8 second, but does not need to perform low-pass filtering if the shutter speed Sp of the mechanical shutter 64 is Sp < 1 / 8 second.

[0199] Furthermore, in the above explanation, the first default time, which is the threshold for whether or not to perform low-pass filtering based on the measurement results shown in Figure 11, is set to 1 / 4 second or 1 / 8 second as an example. However, if, for example, other measurement results other than those shown in Figure 11 are obtained, the first default time may be set to a time other than 1 / 4 second or 1 / 8 second based on the other measurement results.

[0200] Furthermore, in the above embodiment, the CPU 90 performs low-pass filtering when the shutter speed Sp in mechanical shutter mode is the first predetermined time. However, if, for example, any of the above-mentioned other measurement results are obtained, the CPU 90 may or may not perform low-pass filtering when the shutter speed Sp in mechanical shutter mode is the first predetermined time.

[0201] Furthermore, in the above embodiment, when continuous imaging is performed by the image sensor 18 in electronic front curtain shutter mode, the CPU 90 performs normal gain control without performing gain-up control. However, as shown in Figure 18 as an example, the CPU 90 may perform gain-up control when continuous imaging is performed by the image sensor 18 in electronic front curtain shutter mode. In this case, image blur caused by vibrations associated with the driving of the rear curtain 64B of the mechanical shutter 64 during the operation of the electronic front curtain can be suppressed.

[0202] Furthermore, in the above embodiment, a filter arithmetic unit 142 and a control output arithmetic unit 144 are used separately from the CPU 90, but the processing in the filter arithmetic unit 142 and the control output arithmetic unit 144 may be executed by the CPU 90.

[0203] Furthermore, although feedback control was exemplified in the above embodiment, the technology of this disclosure is not limited thereto, and other motion control methods such as feedforward control may also be used.

[0204] Furthermore, in the above embodiment, the vibration sensor 70 is, for example, a gyro sensor, but any sensor capable of detecting vibrations, such as an acceleration sensor, may be used.

[0205] Furthermore, in the above embodiment, the shake correction actuator 102 is provided with a voice coil motor as an example, but any actuator that can move the image sensor 18 in a direction that corrects image shake may be used, such as a stepping motor, a DC motor, or a piezoelectric element.

[0206] Furthermore, in the above embodiment, the position sensor 100 is a sensor that includes a Hall element and a sensor magnet, but any sensor that can detect the position of the image sensor 18 may be used, such as a magnetic sensor or a photosensor.

[0207] Furthermore, although the above embodiment describes an example in which imaging support processing is performed by a controller 78 within the imaging device 10, the technology of this disclosure is not limited thereto. For example, as shown in Figure 19, imaging support processing may be performed by a computer 314 in an external device 312 that is communicably connected to the imaging device 10 via a network 310 such as a LAN or WAN. In the example shown in Figure 19, the computer 314 includes a CPU 316, storage 318, and memory 320. The storage 318 stores the imaging support processing program 180.

[0208] The imaging device 10 requests the external device 312 to perform imaging support processing via the network 310. In response, the CPU 316 of the external device 312 reads the imaging support processing program 180 from the storage 318 and executes the imaging support processing program 180 on the memory 320. The CPU 316 performs imaging support processing according to the imaging support processing program 180 executed on the memory 320. The CPU 316 then provides the processing results obtained from the execution of the imaging support processing to the imaging device 10 via the network 310.

[0209] Furthermore, the imaging device 10 and the external device 312 may perform imaging support processing in a distributed manner, or multiple devices including the imaging device 10 and the external device 312 may perform imaging support processing in a distributed manner. In the example shown in Figure 19, the imaging device 10 and the external device 312 are examples of "imaging devices" related to the technology of this disclosure.

[0210] Furthermore, although the above embodiment described an example in which the imaging support processing program 180 is stored in the NVM92, the technology of this disclosure is not limited thereto. For example, as shown in Figure 20, the imaging support processing program 180 may be stored in a storage medium 330. The storage medium 330 is a non-temporary storage medium. An example of the storage medium 330 is any portable storage medium such as an SSD or a USB memory.

[0211] The imaging support processing program 180 stored in the storage medium 330 is installed in the controller 78. The CPU 90 executes imaging support processing according to the imaging support processing program 180.

[0212] Alternatively, the imaging support processing program 180 may be stored in the memory of another computer or server device connected to the controller 78 via a communication network (not shown), and the imaging support processing program 180 may be downloaded and installed on the controller 78 in response to a request from the imaging device 10.

[0213] Furthermore, it is not necessary to store the entire imaging support processing program 180 in the memory unit of another computer or server device connected to the controller 78, or in the NVM 92; it is acceptable to store only a portion of the imaging support processing program 180.

[0214] In the example shown in Figure 20, the controller 78 is built into the imaging device 10, but the technology of this disclosure is not limited to this, and for example, the controller 78 may be provided outside the imaging device 10.

[0215] In the example shown in Figure 20, CPU90 is a single CPU, but it could be multiple CPUs. Alternatively, a GPU could be used instead of CPU90.

[0216] In the example shown in Figure 20, a controller 78 is illustrated, but the technology of this disclosure is not limited thereto, and devices including ASICs, FPGAs, and / or PLDs may be used instead of the controller 78. Alternatively, a combination of hardware and software configurations may be used instead of the controller 78.

[0217] The hardware resources used to perform the imaging support processing described in the above embodiment include the following types of processors. Examples of processors include a CPU, which is a general-purpose processor that functions as a hardware resource for performing imaging support processing by executing software, i.e., a program. Other examples of processors include dedicated electrical circuits, which are processors with circuit configurations specifically designed to perform particular processing, such as FPGAs, PLDs, or ASICs. Each processor has built-in or connected memory, and each processor performs imaging support processing by using this memory.

[0218] The hardware resources that perform the imaging support processing may consist of one of these various processors, or a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, or a combination of a CPU and an FPGA). Alternatively, the hardware resources that perform the imaging support processing may consist of a single processor.

[0219] Examples of configurations using a single processor include, firstly, a configuration in which one or more CPUs and software are combined to form a single processor, and this processor functions as a hardware resource that performs imaging support processing. Secondly, there is a configuration using a processor that realizes the functions of the entire system, including multiple hardware resources that perform imaging support processing, on a single IC chip, as exemplified by SoCs. In this way, imaging support processing is realized using one or more of the above types of processors as hardware resources.

[0220] Furthermore, the hardware structure of these various processors can more specifically utilize electrical circuits combining circuit elements such as semiconductor devices. Also, the above imaging support processing is merely an example. Therefore, it goes without saying that unnecessary steps can be deleted, new steps added, or the processing order rearranged, as long as it does not deviate from the main purpose.

[0221] The descriptions and illustrations presented above are detailed explanations of the technical aspects of this disclosure and are merely examples of the technical aspects. For example, the above descriptions of the structure, function, operation, and effect are examples of the structure, function, operation, and effect of the technical aspects of this disclosure. Therefore, it goes without saying that you may delete unnecessary parts, add new elements, or replace elements in the descriptions and illustrations presented above, as long as you do not deviate from the essence of the technical aspects of this disclosure. Furthermore, in order to avoid confusion and facilitate understanding of the technical aspects of this disclosure, explanations of common technical knowledge and the like that do not require special explanation to enable the implementation of the technical aspects of this disclosure have been omitted from the descriptions and illustrations presented above.

[0222] In this specification, "A and / or B" is synonymous with "at least one of A and B." That is, "A and / or B" means that it may be A alone, or B alone, or a combination of A and B. Furthermore, in this specification, the same concept as "A and / or B" applies when expressing three or more things linked by "and / or."

[0223] All documents, patent applications, and technical standards described herein are incorporated by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference.

[0224] The following additional information is disclosed regarding the embodiments described above.

[0225] (Note 1) An image sensor having a light-receiving surface, An actuator for moving the image sensor along the light-receiving surface, A processor that controls the actuator, Equipped with, The actuator comprises a first actuator and a second actuator. The processor provides a phase difference between a first drive signal for driving the first actuator and a second drive signal for driving the second actuator. Imaging device. (Note 2) An image sensor having a light-receiving surface, An actuator for moving the image sensor along the light-receiving surface, Equipped with, The actuator has a first voice coil motor and a second voice coil motor arranged side by side. The first voice coil motor has a first coil and a first magnet, The second voice coil motor has a second coil and a second magnet, The winding direction of the first coil is opposite to the winding direction of the second coil. The north and south poles of the first magnet are positioned in opposite directions to the north and south poles of the second magnet. Imaging device.

Claims

1. An image sensor having a light-receiving surface, An actuator for moving the image sensor along the light-receiving surface, Equipped with, The actuator has a first voice coil motor and a second voice coil motor arranged side by side. The first voice coil motor has a first coil and a first magnet, The second voice coil motor has a second coil and a second magnet, The winding direction of the first coil is opposite to the winding direction of the second coil. The north and south poles of the first magnet are arranged in opposite directions to the north and south poles of the second magnet. The first coil and the second coil are connected in parallel to the driver. The direction of the current flowing through the first coil and the direction of the current flowing through the second coil are always opposite. Imaging device.

2. Equipped with movable members and fixed members, The image sensor, the first coil, and the second coil are fixed to the movable member. The first magnet and the second magnet are fixed to the fixing member, The image sensor is arranged alongside the first coil and the second coil in the direction in which the image sensor moves. The movable member has a first support portion that supports the first coil and a second support portion that supports the second coil. The first support portion has a first notch that opens on the side opposite to the image sensor, The second support portion has a second notch that opens on the side opposite to the image sensor, The first coil is positioned inside the first notch. The second coil is located inside the second notch. The imaging apparatus according to claim 1.

3. The actuator has a third voice coil motor and a fourth voice coil motor arranged side by side. The first voice coil motor and the second voice coil motor move the image sensor in the first direction. The third voice coil motor and the fourth voice coil motor move the image sensor in a second direction intersecting the first direction, and rotate it around a third direction intersecting the first and second directions. The imaging apparatus according to claim 1 or claim 2.

4. Equipped with a processor, The processor provides a phase difference between a first drive signal for driving the first voice coil motor and a second drive signal for driving the second voice coil motor. The imaging apparatus according to any one of claims 1 to 3.

5. The first drive signal and the second drive signal are PWM signals, respectively. The imaging apparatus according to claim 4.

6. Equipped with a mechanical shutter and a processor, The aforementioned processor, Based on the vibration of the imaging device, movement control is performed to move the image sensor in a direction that corrects the blur of the image obtained by imaging with the image sensor. In imaging by the image sensor, if the shutter speed of the mechanical shutter is shorter than a first predetermined time, gain-up control is performed to increase the gain of the motion control compared to when the shutter speed of the mechanical shutter is longer than a first predetermined time. The imaging apparatus according to any one of claims 1 to 5.

7. The processor performs the gain-up control when, during imaging by the image sensor, the shutter speed of the mechanical shutter is shorter than the first predetermined time and longer than the second predetermined time. The imaging device according to claim 6.

8. The processor performs the gain-up control in a mechanical shutter mode in which the rear curtain of the mechanical shutter is driven after the front curtain of the mechanical shutter has been driven. The imaging apparatus according to claim 6 or claim 7.

9. In the electronic shutter mode in which the electronic shutter is activated, the processor performs control to set the gain of the movement control to a gain lower than the gain set by the gain-up control. The imaging apparatus according to any one of claims 6 to 8.

10. The processor performs the gain-up control when continuous imaging is performed by the image sensor in an electronic front curtain shutter mode, in which the rear curtain of the mechanical shutter is driven after the electronic front curtain of the image sensor is activated. The imaging apparatus according to any one of claims 6 to 9.

11. The aforementioned processor, In imaging using the image sensor, if the shutter speed of the mechanical shutter is longer than the first predetermined time, the signal obtained due to the vibration of the imaging device is processed with a low-pass filter at a predetermined cutoff frequency. Based on the signal that has been filtered using the low-pass filter, the movement control is performed. The imaging apparatus according to any one of claims 6 to 10.

12. The processor performs the gain-up control when the frequency of the drive signal used for movement control is a second frequency that is higher than the first frequency. The imaging apparatus according to any one of claims 6 to 11.

13. The first predetermined time is 1 / 4 second. The imaging apparatus according to any one of claims 6 to 12.

14. The first predetermined time is 1 / 8 second. The imaging apparatus according to any one of claims 6 to 12.

15. The second predetermined time is 1 / 60 of a second. An imaging apparatus according to claim 7, and any one of claims 8 to 14 dependent on claim 7.

16. The aforementioned second default time is 1 / 30 of a second. An imaging apparatus according to claim 7, and any one of claims 8 to 14 dependent on claim 7.

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