JP2015169928A - Imaging apparatus, control method of the same, program, and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus which can be highly accurately and stably controlled for vibration insulation.SOLUTION: The imaging apparatus includes: correction means configured to be movable in a direction orthogonal to an optical axis of a photographing optical system and correcting image blur generated by shake; position detection means for detecting a position of the correction means; first amplification means for amplifying an output signal of the position detection means; second amplification means for amplifying an output signal of the first amplification means; first AD conversion means for converting the output signal of the first amplification means from analog to digital and outputting a first signal; second AD conversion means for converting the output signal of the second amplification means from analog to digital and outputting a second signal; and control means for controlling the correction means on the basis of the first signal and second signal.

Description

  The present invention relates to an imaging apparatus having a camera shake correction function.

  2. Description of the Related Art Conventionally, an imaging apparatus including a correction unit (shift lens) that corrects image blur caused by shake of the imaging apparatus is known. Patent Document 1 is configured to widen the AD conversion range of the AD converter when the output range (or movable stroke amount) of the Hall element that detects the position of the shift lens is wider than the convertible range of the AD converter. An imaging device is disclosed. Specifically, a bias voltage (D / A value) is applied to the input part of an amplifier for amplifying the output signal of the Hall element using a D / A converter, and the output of the Hall element is the output of the AD converter. It is set so that it can be converted.

JP 2009-49569 A

  However, in the configuration of Patent Document 1, it is necessary to change the bias voltage (D / A value) every time the position of the shift lens is out of the AD conversion range. When the bias voltage is changed, the output voltage of the amplifier is not switched instantaneously, and a transient response occurs. For this reason, when the position of the shift lens is controlled at a high-speed sampling cycle (for example, 10 kHz), the shift lens control is disturbed at the time of switching. As described above, if the AD resolution is increased to improve the position control accuracy of the shift lens and only a narrow range is subjected to AD conversion, the position control becomes unstable when a large disturbance is applied.

  Therefore, the present invention provides an imaging device capable of highly accurate and stable image stabilization control, a method for controlling the imaging device, a program, and a storage medium.

  An imaging apparatus according to one aspect of the present invention is configured to be movable in a direction orthogonal to the optical axis of a photographing optical system, and corrector that corrects image blur caused by shake, and position detection that detects the position of the corrector. Means, a first amplifying means for amplifying the output signal of the position detecting means, a second amplifying means for amplifying the output signal of the first amplifying means, and AD converting the output signal of the first amplifying means. A first AD converter that outputs a first signal; a second AD converter that AD-converts an output signal of the second amplifier; and outputs a second signal; and the correction based on the first signal and the two signals Control means for controlling the means.

  According to another aspect of the present invention, there is provided a method for controlling an imaging apparatus, the step of detecting a position of a correction unit that corrects image blur caused by shake using a position detection unit, and the position of the position using a first amplification unit. Amplifying the output signal of the detection means to obtain a first signal; using the second amplification means to amplify the output signal of the first amplification means to obtain a second signal; and And a step of controlling the correction means based on the signal and the two signals.

  A program according to another aspect of the present invention is configured to cause a computer to execute a method for controlling the imaging apparatus.

  A storage medium according to another aspect of the present invention stores the program.

  Other objects and features of the present invention are illustrated in the following examples.

  According to the present invention, it is possible to provide an imaging apparatus capable of performing highly accurate and stable image stabilization control, a method for controlling the imaging apparatus, a program, and a storage medium.

It is a block diagram of the imaging device in this embodiment. It is a basic lineblock diagram of a vibration proof control part in this embodiment. It is a control response diagram of the shift lens in the present embodiment. It is a block diagram of the vibration proof control part in this embodiment. It is a schematic diagram of AD resolution in this embodiment. It is a control response diagram of the shift lens in the present embodiment. It is a related figure of AD value of the amplifier in this embodiment. It is a flowchart which calculates the correction coefficient of AD value of the amplifier in this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, with reference to FIG. 1, the structure of the imaging device in this embodiment is demonstrated. FIG. 1 is a block diagram of an imaging apparatus 100 (digital still camera) in the present embodiment.

  In FIG. 1, a zoom unit 101 includes a zoom lens that performs zooming. The zoom drive control unit 102 drives and controls the zoom unit 101. The correction lens unit 103 (correction means) has a correction lens (shift lens) that can move in a direction orthogonal to the optical axis OA of the photographing optical system. The correction lens has, for example, a circular movable range having a predetermined size centered on the optical axis OA. With such a configuration, the correction lens unit 103 can correct image blur caused by shake of the imaging apparatus 100.

  The image stabilization control unit 104 includes, for example, an angular velocity sensor or an acceleration sensor (shake detection unit 1043), and detects a shake (hand shake) of the imaging apparatus 100. In addition, the image stabilization control unit 104 controls the driving of the correction lens so as to correct the blur of the captured image (image blur) due to the shake of the imaging device 100. The correction lens drive method (correction lens drive range, drive pattern, etc.) by the image stabilization control unit 104 depends on correction information (correction parameter or camera shake correction parameter) set in the image stabilization control unit 104 by the camera control unit 118 described later. It can be controlled. In addition, information (parameter set) corresponding to a plurality of camera shake correction functions that can be realized by the image stabilization control unit 104 can be prepared in advance. In this case, the camera control unit 118 may control the operation of the image stabilization control unit 104 by setting identification information of a camera shake correction function for enabling or disabling the function of the image stabilization control unit 104.

  The aperture / shutter unit 105 includes, for example, a mechanical shutter that also serves as an aperture. The aperture / shutter drive control unit 106 controls driving of the aperture / shutter unit 105. The focus unit 107 includes a lens (focus lens) that performs focus adjustment. The focus drive control unit 108 controls the drive of the focus unit 107. The zoom unit 101, the correction lens unit 103, the aperture / shutter unit 105, and the focus unit 107 constitute a photographing optical system (photographing lens) that forms a subject image (optical image).

  In the present embodiment, the photographing lens (lens device) is configured integrally with an imaging device main body (camera main body) including the imaging unit 109. However, the present embodiment is not limited to this, and the photographing lens may be an interchangeable lens that is detachably attached to the imaging apparatus main body. When the photographing lens is an interchangeable lens, the image stabilization control unit 104 may be provided in the interchangeable lens. Further, a lens control unit (not shown) provided in the interchangeable lens may be configured to execute at least a part of the function of the camera control unit 118.

  The imaging unit 109 includes an imaging element such as a CMOS sensor or a CCD sensor, and photoelectrically converts an optical image formed through the photographing lens into an electrical signal. In this embodiment, the image stabilization control unit 104 controls the driving of the image sensor so as to correct the blur of the captured image (image blur) due to the shake of the imaging device 100 instead of the drive control of the correction lens. It may be configured. Even with such a configuration, the same anti-vibration effect as in the present embodiment can be obtained.

  The imaging signal processing unit 110 converts the electrical signal output from the imaging unit 109 into a video signal. The video signal processing unit 111 processes the video signal output from the imaging signal processing unit 110 according to the application. The display unit 112 displays a live view image as necessary based on the signal output from the video signal processing unit 111, and functions as an electronic viewfinder (EVF). The power supply unit 113 supplies power to the entire imaging device 100 (each unit) according to the application. The external input / output terminal unit 114 inputs / outputs communication signals and video signals to / from external devices and networks. The operation unit 115 is an input device group such as buttons, keys, and a touch panel for a user to input various instructions to the imaging apparatus 100. The storage unit 116 stores various data such as video information.

  The posture information control unit 117 determines the posture (for example, vertical position or horizontal position) of the imaging device 100 and provides the posture information of the imaging device 100 to the display unit 112 and the video signal processing unit 111 based on the determination result. To do. The camera control unit 118 controls the entire imaging apparatus 100. The camera control unit 118 is a programmable processor such as a CPU, for example. The camera control unit 118 executes, for example, a control program stored in the storage unit 116 to control each unit of the imaging apparatus 100 to realize various functions of the imaging apparatus 100. Note that at least one of the imaging signal processing unit 110 and the video signal processing unit 111 may be realized by software by the camera control unit 118. Alternatively, at least a part of the functions realized by the camera control unit 118 may be realized by hardware such as an ASIC or an electronic circuit.

  Next, main operations of the imaging apparatus 100 will be described. The operation unit 115 includes an anti-vibration switch for setting whether the shake correction function (anti-vibration function) is valid or invalid. When a mode in which the shake correction function is effective (a shake correction mode or a shake prevention mode) is selected by the shake prevention switch, the camera control unit 118 instructs the image stabilization control unit 104 to start the image stabilization operation. The image stabilization control unit 104 instructed to start the image stabilization operation performs the image stabilization operation until an instruction to end the image stabilization operation is given.

  The operation unit 115 includes a shooting mode selection switch for setting a shooting mode. The imaging apparatus 100 is configured to be able to select, for example, a still image shooting mode or a moving image shooting mode as a shooting mode. In accordance with the shooting mode set by the shooting mode selection switch, the camera control unit 118 can change the operating condition of the driving member (for example, actuator) of the correction lens.

  In addition, the operation unit 115 includes a shutter release button configured such that the first switch (SW1) and the second switch (SW2) are sequentially turned on in accordance with the pressing amount. The shutter release button has a structure in which the first switch (SW1) is turned on when the shutter release button is depressed about half, and the second switch (SW2) is turned on when the shutter release button is pushed down to the end.

  When the first switch (SW1) is turned on, the focus drive control unit 108 performs AF evaluation based on the image processed by the imaging signal processing unit 110 or the video signal processing unit 111 in accordance with an instruction from the camera control unit 118. A value (contrast evaluation value or focus signal) is calculated. The focus drive control unit 108 drives the focus unit 107 based on the calculated AF evaluation value, and performs contrast type focus control (focus control). However, the present embodiment is not limited to this, and the focus drive control unit 108 may perform focus control by a phase difference detection method using an external measurement sensor or the like. When the first switch (SW1) is turned on, for example, the camera control unit 118 determines a shooting condition for obtaining an appropriate exposure amount from an image processed by the imaging signal processing unit 110 or the video signal processing unit 111. To do.

  When the second switch (SW2) is turned on, the aperture / shutter drive control unit 106 drives the aperture / shutter unit 105 according to the determined imaging condition to expose the imaging unit 109. At this time, the imaging unit 109 photoelectrically converts the optical image and outputs an electrical signal. Thereafter, the imaging signal processing unit 110 performs AD conversion processing, color interpolation processing, white balance adjustment processing, gamma correction processing, and the like, and image data (captured image data) is stored in the storage unit 116.

  The operation unit 115 includes a moving image recording switch. When the moving image recording switch is pressed, the camera control unit 118 starts recording a moving image in the storage unit 116. When the moving image recording switch is pressed again during moving image recording, the camera control unit 118 ends the recording of the moving image. The operation unit 115 includes a reproduction mode selection switch for selecting a reproduction mode. When the playback mode is selected, the camera control unit 118 stops the image stabilization operation by the image stabilization control unit 104. The operation unit 115 also includes a zoom switch that changes the zoom of the photographing lens. When a magnification change instruction is input by the zoom switch, the zoom drive control unit 102 instructed via the camera control unit 118 drives the zoom unit 101 in the instructed direction.

  Next, the basic configuration of the correction lens unit 103 and the image stabilization control unit 104 in the present embodiment will be described with reference to FIG. FIG. 2 is a basic configuration diagram of the correction lens unit 103 and the image stabilization control unit 104 (hall output unit).

  The hall element 1041 is position detection means for detecting the position of the shift lens 1031 (correction lens unit 103). The hall element 1041 outputs a voltage according to the magnetic force from the magnet 1032 for detecting the position of the shift lens 1031. The amplifier AMP1 (first amplification means) amplifies the voltage (output signal) output from the Hall element 1041. The amplifier AMP2 (second amplification means) amplifies the voltage (output signal) output from the amplifier AMP1. The AD converter 1045 (second AD conversion means) performs AD conversion on the voltage (analog signal) output from the amplifier AMP2, and outputs a digital signal. The shift lens control unit 1046 performs feedback control (PID control) of the shift lens 1031 based on the output signal from the AD converter 1045.

  The output offset correction unit 1042 performs output offset correction in order to align the output signal (output value) of the Hall element 1041 with the reference value in the amplifier AMP1. In the present embodiment, the output signal of the amplifier AMP2 is used when aligning the output signal of the Hall element 1041 with the reference value. In the present embodiment, the amplification factors of the amplifier AMP1 and the amplifier AMP2 are different from each other.

  As shown in FIG. 2, the present embodiment is configured to amplify the output signal of the Hall element 1041 using a two-stage amplifier. This is because the amplification magnification and the output offset correction width can be set large. The output value of the Hall element 1041 varies greatly due to variations in the mechanical configuration (for example, an error in the mounting position of the magnet 1032 or the Hall element 1041 or a magnetization deviation of the magnet 1032), or variations in the output of the Hall element 1041 itself. have. The voltage range used in the output offset correction is a predetermined range (for example, 0 to 3 [V]). For this reason, when the output value of the Hall element 1041 varies beyond the range (correction voltage width), correction cannot be performed. In this case, the amplifier of the output signal from the Hall element 1041 has a two-stage configuration (the correction amount for the amplifier AMP1 is further amplified by the amplifier AMP2), and a larger correction amount can be obtained. With such a configuration, even when the variation due to the mechanical configuration and the variation of the Hall element 1041 itself are large, sufficient output offset correction can be performed.

  Here, with reference to FIG. 3, the control response of the shift lens 1031 when only the AD conversion value of the amplifier AMP2 (output value of the AD converter 1045) is used in the still image shooting mode will be described. FIG. 3 is a control response diagram of the shift lens 1031 when only the AD conversion value of the amplifier AMP2 is used in the still image shooting mode.

  Here, as shown in FIG. 3, in the still image shooting mode, for example, it is assumed that the AD conversion value is 400 with respect to a correction angle of 0.4 degrees at the telephoto end. When the camera is held firmly during normal still image shooting, the amount of camera shake is not large, and the position of the shift lens 1031 often falls within the AD conversion range (AD conversion value: 0 to 800) (area A). On the other hand, when a large force (disturbance) is applied to the shift lens 1031 such as shaking the imaging apparatus 100 with a steep movement such as a large pan operation, the shift lens 1031 falls outside the AD conversion range (region B).

  If feedback control is performed in a state where the position of the shift lens 1031 cannot be accurately detected, the amount of return for feedback increases and overshoot occurs. When the shift lens 1031 moves to a position that exceeds the AD conversion range again due to such overshoot, the return amount becomes large again. As a result, the controllability is lowered due to the deterioration of the convergence of the shift lens 1031 to the target position. Therefore, in this embodiment, the configuration shown in FIG. 4 is adopted.

  FIG. 4 is a configuration diagram of the correction lens unit 103 and the image stabilization control unit 104 (hall output unit) in the present embodiment. As shown in FIG. 4, in the present embodiment, in addition to the configuration of FIG. 2, an AD converter 1044 (A / D converter 1044) that AD-converts the output signal of the amplifier AMP1 (first amplification means) that amplifies the output signal of the Hall element 1041. First AD conversion means) is provided. The shift lens control unit 1046 performs feedback control (PID control) of the shift lens 1031 by combining the AD conversion values of the AD converters 1044 and 1045. In this embodiment, the AD conversion bit lengths of the amplifiers AMP1 and AMP2 (AD converters 1044 and 1045) are the same bit length, but the present invention is not limited to this, and the bit lengths may be different from each other. .

  Next, the resolution (AD resolution) when the output value of the amplifier AMP1 (AD converter 1044) and the output value of the amplifier AMP2 (AD converter 1045) are combined will be described with reference to FIG. FIG. 5 is a schematic diagram of the AD resolution when the output value of the amplifier AMP1 and the output value of the amplifier AMP2 are combined. Here, it is assumed that the amplification factor of the amplifier AMP2 is 4 and the AD resolution of the amplifier AMP2 is 400 LSB per 0.4 degrees. The AD resolution of the amplifier AMP1 is determined according to the amplification factor of the amplifier AMP2 and the AD resolution, and is 400 LSB per 1.6 degrees in this embodiment.

  When the output signal of the Hall element 1041 is amplified using the two-stage amplifiers AMP1 and AMP2 as in the present embodiment, the AD values before and after the second-stage amplification (the respective AD conversion values of the amplifiers AMP1 and AMP2) ). For example, the AD conversion value of the amplifier AMP2 is used for an area where the position of the shift lens 1031 needs to be AD converted with high accuracy. On the other hand, when the shift lens 1031 is largely moved due to a large panning operation or the like, the resolution becomes slightly coarse, but the AD conversion value of the amplifier AMP1 is used for an area where the position of the shift lens 1031 needs to be grasped in a wide range. Thereby, highly accurate position detection of the shift lens 1031 and wide-range position detection can be made compatible.

  FIG. 6 is a control response diagram of the shift lens 1031 when the AD converter 1044 is provided. In the range A (second state in which the shake is smaller than the predetermined value) in FIG. 6, the AD conversion value (second signal) of the amplifier AMP2 (AD converter 1045) is used. In regions B and C (first state in which the shake is greater than or equal to a predetermined value) in FIG. 6, the AD conversion value (first signal) of the amplifier AMP1 (AD converter 1044) is used. As a result, as shown by the thick black line in FIG. 6, even when the shift lens 1031 moves greatly due to a large panning operation or a disturbance, the overshoot can be reduced and the convergence to the target position can be accelerated. .

  However, when using a combination of AD conversion values as described above, it may be difficult to perform control by simply combining the AD conversion values of the amplifiers AMP1 and AMP2. This is because, as shown in FIG. 4, the output offsets of the amplifiers AMP1 and AMP2 and the amplification factor of the amplifier AMP2 are different for each design, and even in the same design, variations in amplification factor due to device variations occur. This is shown in FIG. FIG. 7 is a relationship diagram of AD conversion values (AD values) of the amplifiers AMP1 and AMP2 in the present embodiment. As shown in FIG. 7, the center AD values of the amplifiers AMP1 and AMP2 may be shifted from each other due to the above-described factors. Therefore, in this embodiment, it is preferable to correct this deviation.

  With reference to FIG. 8, a description will be given of a process for correcting a shift that occurs when two AD conversion values are used in combination. FIG. 8 is a flowchart illustrating a correction coefficient calculation method (control method for the imaging apparatus 100) for correcting the shift. Each step in FIG. 8 is mainly executed by the camera control unit 118. However, at least a part of each step may be executed by the shift lens control unit 1046 of the image stabilization control unit 104 based on a command from the camera control unit 118. The camera control unit 118 and the shift lens control unit 1046 constitute a control unit in this embodiment.

  First, in step S101, the camera control unit 118 fixes the shift lens 1031 at the center (center position) and sets the camera shake correction function to OFF in order to calculate the reference of the AD values of the amplifiers AMP1 and AMP2. In step S102, the camera control unit 118 (shift lens control unit 1046) sets the AD values (AD conversion values) of the amplifiers AMP1 and AMP2 (AD converters 1044 and 1045) with the shift lens 1031 fixed at the center. get.

Subsequently, in step S103, the camera control unit 118 calculates a reference value (first reference value) of the amplifier AMP1. Here, the AD value of the amplifier AMP2 is set to be a reference value (second reference value) (for example, 400 in this embodiment). For this reason, the AD value of the amplifier AMP1 deviates from the AD value of the amplifier AMP2 (400 in this embodiment) due to the output offset of the amplifier AMP1 and the deviation of the reference voltage Vref of the amplifier AMP2. In the present embodiment, the AD value of the amplifier AMP1 at this time is set as the reference value (first reference value) of the amplifier AMP1. When the displacement amount (difference between a reference value of the reference value and the amplifier AMP2 of the amplifier AMP2) and delta _offset, the reference value of the AMP1 (first reference value), the amount of deviation from the reference value of the AMP2 (second reference value) A value obtained by subtracting _Δoffset . As described above, steps S101 to S103 are steps of calculating the first reference value output from the amplifier AMP1 based on the second reference value output from the amplifier AMP2 in a state where the correction lens unit 103 is fixed.

  In step S104, the camera control unit 118 turns on the camera shake correction function and starts camera shake correction. When the camera shake correction function is on, the shift lens 1031 moves in the direction orthogonal to the optical axis in accordance with the shaking state (vibration state) of the imaging apparatus 100, and the output values (AD values) of the amplifiers AMP1 and AMP2 change. . In step S105, the camera control unit 118 (shift lens control unit 1046) acquires both AD values of the amplifiers AMP1 and AMP2. At this time, the AD values of the amplifiers AMP1 and AMP2 can be acquired simultaneously.

  Subsequently, in step S106, the camera control unit 118 determines whether or not the AD value of the amplifier AMP2 is not a reference value (second reference value) and is within a predetermined range (for example, within 400 ± 300). If the AD value of the amplifier AMP2 is the reference value or outside the predetermined range, the process returns to step S105. Then, the camera control unit 118 (shift lens control unit 1046) acquires the AD value of the amplifier AMP2 again. On the other hand, if the AD value of the amplifier AMP2 is not the reference value and is within the predetermined range, the process proceeds to step S107.

  In step S107, the camera control unit 118 calculates a correction coefficient α (correction information) for the AD value of the amplifier AMP1. In the present embodiment, the calculation of the reference value (first reference value) of the amplifier AMP1 in step S103 and the calculation of the correction coefficient α of the amplifier AMP1 in step S107 are preferably executed a predetermined number of times to increase the accuracy. In the present embodiment, the correction coefficient α of the amplifier AMP1 can be calculated as in the following formula (1).

Correction coefficient α = (AD value of AMP2−reference value of AMP2) ÷ (AD value of AMP1−reference value of AMP1) (1)
As described above, in steps S104 to S107, the correction coefficient α is calculated using the first signal and the second signal obtained while the correction lens unit 103 is driven, and the first reference value and the second reference value. It is a process.

  Subsequently, the AD value (first signal) of the amplifier AMP1 is calculated using the correction coefficient α calculated by the equation (1) and the reference value (first reference value) of the amplifier AMP1 calculated in step S103. , Converted to the AD range (AD conversion range) of the amplifier AMP2. The converted AD value (converted AD value) can be expanded as shown in the following equation (2).

Conversion AD value = ((AD value of AMP1−reference value of AMP1) × correction coefficient α + reference value of AMP2) (2)
When the shift lens 1031 is within the AD conversion range of the amplifier AMP2 (in the second state), the shift lens control unit 1046 performs high-precision feedback control with high AD resolution based on the AD value of the amplifier AMP2. On the other hand, when the shift lens 1031 moves out of the AD conversion range of the amplifier AMP2 due to a large panning operation or disturbance (in the second state), the shift lens control unit 1046 calculates the converted AD value calculated by Expression (2). Is used to perform stable feedback control.

  In the present embodiment, the camera control unit 118 first fixes the shift lens 1031 at the center for a predetermined time (for example, 100 ms) in order to obtain the reference value of the amplifier AMP1 after the imaging apparatus 100 is activated. Thereafter, the correction coefficient α of the amplifier AMP1 is calculated during normal camera shake correction. For this reason, since the camera control unit 118 can automatically correct the correction coefficient α, it is possible to eliminate the need to adjust the correction coefficient in the shipping process of the imaging apparatus 100. Even if the characteristics of the image stabilization control unit 104 (hall output configuration unit) change in the temperature environment, the correction coefficient α can be automatically calculated every time the image pickup apparatus 100 is activated. Can be done.

  In this embodiment, an example of the still image shooting mode has been described. However, the present embodiment can be applied to other modes such as an image stabilization off mode (ISOFF), a tripod processing mode, or a movie shooting mode in the still image shooting mode. Applicable. Even when the AD resolution of the amplifier AMP2 is switched to be high in order to improve the control accuracy of the shift lens 1031, the conversion correction of the AD value of the first-stage amplifier AMP1 is performed in the same procedure as described above. Can be automatically performed again. Further, even when the AD resolution of the amplifier AMP2 is switched to a lower value in order to further increase the movable range during moving images, the AD value conversion correction of the first-stage amplifier AMP1 can be automatically performed again in the same manner.

  In the present embodiment, the digital still camera capable of capturing still images and moving images has been described as the imaging device, but the present invention is not limited to this. For example, the present embodiment can be applied to an electronic device such as a game machine having a photographing function, a communication device such as a mobile phone having a photographing function, and the same effect can be obtained. In the above-described embodiment, only the lens shift type shake correction mechanism has been described. However, the principle of this embodiment is similarly applied to other optical shake correction mechanisms, for example, a sensor shift type shake correction mechanism. Applicable.

  As described above, in the present embodiment, the first AD converter (AD converter 1044) AD-converts the output signal of the first amplifier (amplifier AMP1) and outputs the first signal. The second AD conversion means (AD converter 1045) AD-converts the output signal of the second amplification means (amplifier AMP2) and outputs the second signal. The control unit (shift lens control unit 1046, camera control unit 118) controls the correction unit (correction lens unit 103) based on the first signal and the second signal. Preferably, the control means performs feedback control of the correction means based on position information obtained by combining the first signal and the second signal. Preferably, the first signal has a first resolution, and the second signal has a second resolution higher than the first resolution.

  Preferably, the control unit calculates a correction coefficient (correction information) for reducing an output offset between the first amplification unit and the second amplification unit. Preferably, the control means controls the correction means based on the first signal in the first state where the shake is a predetermined amount or more. On the other hand, in the second state in which the shake is smaller than the predetermined amount, the correction unit is controlled based on the second signal. More preferably, in the first state, the control means converts the first signal obtained from the first AD conversion means to the AD conversion range of the second AD conversion means using the correction information, and converts the first signal to the converted first signal. Based on this, the correction means is controlled.

  The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads the program. To be executed.

  According to the present embodiment, it is possible to ensure an AD conversion range corresponding to a large shake such as walking while performing position control of the shift lens with high accuracy. For this reason, according to the present embodiment, it is possible to provide an imaging apparatus capable of performing highly accurate and stable image stabilization control, a method for controlling the imaging apparatus, a program, and a storage medium.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

100 Imaging device 103 Correction lens unit (correction means)
1041 Hall element (position detection means)
1044 AD converter (first AD conversion means)
1045 AD converter (second AD conversion means)
1046 Shift lens control unit (control means)
AMP1 amplifier (first amplification means)
AMP2 amplifier (second amplification means)

Claims (13)

A correction unit configured to be movable in a direction orthogonal to the optical axis of the imaging optical system, and correcting image blur caused by shake;
Position detecting means for detecting the position of the correcting means;
First amplification means for amplifying an output signal of the position detection means;
Second amplification means for amplifying the output signal of the first amplification means;
First AD converting means for AD converting the output signal of the first amplifying means and outputting a first signal;
Second AD converting means for AD converting the output signal of the second amplifying means and outputting a second signal;
An imaging apparatus comprising: control means for controlling the correction means based on the first signal and the two signals.   The imaging apparatus according to claim 1, wherein the control unit performs feedback control of the correction unit based on position information obtained by combining the first signal and the second signal. The first signal has a first resolution;
The imaging apparatus according to claim 1, wherein the second signal has a second resolution higher than the first resolution.   4. The control unit according to claim 1, wherein the control unit calculates correction information for reducing an output offset between the first amplification unit and the second amplification unit. 5. Imaging device. The control means includes
In the first state where the shake is a predetermined amount or more, the correction unit is controlled based on the first signal,
The imaging apparatus according to claim 4, wherein the correction unit is controlled based on the second signal in a second state in which the shake is smaller than the predetermined amount.   In the first state, the control unit converts the first signal obtained from the first AD conversion unit into an AD conversion range of the second AD conversion unit using the correction information, and converts the first signal after the conversion. The imaging apparatus according to claim 5, wherein the correction unit is controlled based on a signal. Further comprising shake detection means for detecting the shake;
The imaging apparatus according to claim 1, wherein the correction unit corrects the image blur caused by the shake.   The imaging apparatus according to claim 1, wherein the correction unit is a shift lens. Detecting a position of a correction means for correcting image blur caused by shake using a position detection means;
Amplifying an output signal of the position detecting means using a first amplifying means to obtain a first signal;
Using a second amplifying means to amplify the output signal of the first amplifying means to obtain a second signal;
And a step of controlling the correction means based on the first signal and the two signals. Obtaining the first signal comprises:
The method for controlling an imaging apparatus according to claim 9, further comprising: calculating correction information for reducing an output offset between the first amplifying unit and the second amplifying unit. The step of calculating the correction information includes:
Calculating a first reference value output from the first amplifying means based on a second reference value output from the second amplifying means in a state where the correction means is fixed;
Calculating the correction information using the first signal and the second signal obtained during driving of the correction means, and the first reference value and the second reference value. The method of controlling an imaging apparatus according to claim 10, wherein   A program configured to cause a computer to execute the control method for an imaging apparatus according to any one of claims 9 to 11.   A storage medium storing the program according to claim 12.