Patent Publication Number: US-7720367-B2

Title: Anti-shake apparatus

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an anti-shake apparatus for a photographing device, that effectively performs an anti-shake operation for correcting hand-shake caused by roll. 
   2. Description of the Related Art 
   An anti-shake apparatus for a photographing device is proposed. The anti-shake apparatus corrects for the effects of hand-shake by moving a hand-shake-correcting lens or by moving an imaging device in a plane perpendicular to the optical axis, in accordance with the amount of hand-shake which occurs during the imaging process. 
   Japanese unexamined patent publication (KOKAI) No. 2006-71743 discloses an anti-shake apparatus that calculates an anti-shake operation on the basis of a hand-shake angle caused by yaw, a hand-shake angle caused by pitch, and a hand-shake angle caused by roll, and then performs an anti-shake operation on the basis of the hand-shake angles. 
   However, a characteristic of the lens, in particular, the resolution at the edge of the lens is not considered in the anti-shake operation. When the resolution at the edge of the lens is low, the effect of the anti-shake operation for correcting hand-shake caused by roll can not be visually confirmed. 
   SUMMARY OF THE INVENTION 
   Therefore, an object of the present invention is to provide an anti-shake apparatus (an image-stabilization apparatus) that can effectively perform the anti-shake operation for correcting hand-shake caused by roll, inconsideration of the lens characteristics. 
   According to the present invention, an anti-shake apparatus (an image-stabilization apparatus) of a photographing device comprises a movable unit and a controller. The movable unit has an imaging device and is movable and rotatable for an anti-shake operation. The controller controls the movable unit for the anti-shake operation. The controller obtains information regarding a resolution at the edge of a lens that is used for an imaging operation of the imaging device. The controller controls a degree of the anti-shake operation that is performed for correcting hand-shake caused by roll, on the basis of the resolution at the edge of the lens. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The objects and advantages of the present invention will be better understood from the following description, with reference to the accompanying drawings in which: 
       FIG. 1  is a perspective rear view of the embodiment of the photographing device viewed from the back side; 
       FIG. 2  is a front view of the photographing device; 
       FIG. 3  is a circuit construction diagram of the photographing device; 
       FIG. 4  is a flowchart that shows the main operation of the photographing device; 
       FIG. 5  is a flowchart that shows the detail of the interrupt process of the timer; 
       FIG. 6  illustrates calculations in the anti-shake operation; 
       FIG. 7  is a construction diagram of the movable unit; and 
       FIG. 8  is a timing chart of the main operation of the photographing device and the anti-shake operation. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention is described below with reference to the embodiment shown in the drawings. In the embodiment, the photographing device  1  is a digital camera. The camera lens  67  of the photographing device  1  has an optical axis LX. 
   By way of orientation in the embodiment, a first direction x, a second direction y, and a third direction z are defined (see  FIG. 1 ). The first direction x is the direction perpendicular to the optical axis LX. The second direction y is the direction perpendicular to the optical axis LX and the first direction x. The third direction z is the direction parallel to the optical axis LX and perpendicular to both the first direction x and the second direction y. 
   The imaging part of the photographing device  1  comprises a PON button  11 , a PON switch  11   a , a photometric switch  12   a , a release button  13 , a release switch  13   a  for an exposure operation, an anti-shake button  14 , an anti-shake switch  14   a , a display  17  such as an LCD monitor etc., a mirror-aperture-shutter unit  18 , a DSP  19 , a CPU  21 , an AE (automatic exposure) unit  23 , an AF (automatic focus) unit  24 , an imaging unit  39   a  in the anti-shake unit  30 , and a camera lens  67  (see  FIGS. 1 ,  2 , and  3 ). 
   Whether the PON switch  11   a  is in the ON state or the OFF state, is determined by the state of the PON button  11 , so that the ON/OFF states of the photographing device  1  correspond to the ON/OFF states of the PON switch  11   a.    
   The photographic subject image is captured as an optical image through the camera lens  67  by the imaging unit  39   a , and the captured image is displayed on the display  17 . The photographic subject image can be optically observed by the optical finder (not depicted). 
   When the release button  13  is partially depressed by the operator, the photometric switch  12   a  changes to the ON state so that the photometric operation, the AF sensing operation, and the focusing operation are performed. 
   When the release button  13  is fully depressed by the operator, the release switch  13   a  changes to the ON state so that the imaging operation by the imaging unit  39   a  (the imaging apparatus) is performed, and the captured image is stored. 
   The CPU  21  performs a release sequence operation after the release switch  13   a  is set to the ON state. 
   The mirror-aperture-shutter unit  18  is connected to port P 7  of the CPU  21  and performs an UP/DOWN operation of the mirror (a mirror-up operation and a mirror-down operation), an OPEN/CLOSE operation of the aperture, and an OPEN/CLOSE operation of the shutter corresponding to the ON state of the release switch  13   a.    
   The camera lens  67  is an interchangeable lens of the photographing device  1  and is connected to port P 8  of the CPU  21 . The camera lens  67  outputs information regarding the resolution at the edge of the camera lens  67 , and the lens coefficient F, etc., as lens information, stored in a built-in ROM in the camera lens  67 , to the CPU  21 , when the photometric operation is performed. 
   The value of the resolution at the edge of the camera lens  67  is the contrast value at the point on the camera lens  67  whose radial distance from the center of the image has a predetermined length, and is obtained from the MTF (Modulation Transfer Function) or a comparable characteristic of the camera lens  67  (for example aperture and focal length). 
   The DSP  19  is connected to port P 9  of the CPU  21 , and it is connected to the imaging unit  39   a . Based on a command from the CPU  21 , the DSP  19  performs the calculation operations, such as the image-processing operation etc., on the image signal obtained by the imaging operation of the imaging unit  39   a.    
   The CPU  21  is a control apparatus that controls each part of the photographing device  1  in its imaging and anti-shake operation (i.e. the image-stabilization operation). The anti-shake operation includes both the movement of the movable unit  30   a  and position-detection efforts. 
   Furthermore, the CPU  21  stores the value of the anti-shake parameter SR that indicates whether the photographing device  1  is in the anti-shake mode or not, the value of the release-state parameter RP, the value of the mirror state parameter MP, and the value of the lens resolution parameter RMTF. 
   The value of the release-state parameter RP changes with respect to the release sequence operation. When the release sequence operation is performed, the value of the release-state parameter RP is set to 1 (see steps S 21  to S 31  in  FIG. 4 ), otherwise, the value of the release-state parameter RP is set (reset) to 0 (see steps S 13  and S 31  in  FIG. 4 ). 
   When the mirror-up operation is being performed before the exposure operation for the imaging operation, the value of the mirror state parameter MP is set to 1 (see step S 22  in  FIG. 4 ); otherwise, the value of the mirror state parameter MP is set to 0 (see step S 24  in  FIG. 4 ). 
   Whether the mirror-up operation of the photographing device  1  is finished is determined by the detection of the ON/OFF states of the mechanical switch (not depicted). Whether the mirror-down operation of the photographing device  1  is finished is determined by the detection of the completion of the shutter charge. 
   The value of the lens resolution parameter RMTF is set to 1 when the value of the resolution at the edge of the camera lens  67  is greater than a threshold value. In this case, the rotational direction component of the position S n , Sθ n , is calculated on the basis of the hand-shake angle caused by roll. In other words, it is calculated based on the third digital displacement angle Kθ n , so that an anti-shake operation for correcting hand-shake caused by pitch, yaw, and roll, is performed. 
   The value of the lens resolution parameter RMTF is set to 0 when the value of the resolution at the edge of the camera lens  67  is not greater than the threshold value. In this case, the rotational direction component of the position S n , Sθ n , is set to 0 so that the anti-shake operation for correcting hand-shake caused by pitch and yaw is performed without considering the hand-shake caused by roll. 
   When the resolution at the edge of the camera lens  67  is low, the anti-shake operation for correcting hand-shake caused by roll is not effective even if the anti-shake operation considers the roll. Furthermore, correcting for roll limits the range of movement of the movable unit  30   a  available for correction of hand-shake caused by pitch and yaw. Therefore, the anti-shake operation for correcting for roll including the rotation of the movable unit  30   a  is stopped in this case. 
   Therefore, the CPU  21  controls whether the anti-shake operation is performed for correcting hand-shake caused by roll, on the basis of the resolution at the edge of the camera lens  67 . 
   Furthermore, the CPU  21  stores the values of the first digital angular velocity signal Vx n , the second digital angular velocity signal Vy n , the third digital angular velocity signal Vθ n , the first digital angular velocity VVx n , the second digital angular velocity VVy n , the third digital angular velocity VVθ n , the digital displacement angle Kx n  (the hand-shake angle caused by yaw), the second digital displacement angle Ky n  (the hand-shake angle caused by pitch), the third digital displacement angle Kθ n  (the hand-shake angle caused by roll), the horizontal direction component of the position S n , Sx n , the vertical direction component of the position S n , Sy n , the rotational direction component (an inclination angle) of the position S n , Sθ n , the first vertical direction component of the first driving point, Syl n , the second vertical direction component of the second driving point, Syr n , the horizontal driving force Dx n , the first vertical driving force Dyl n , the second vertical driving force Dyr n , the horizontal direction component of the position P n  after A/D conversion, pdx n , the first vertical direction component of the position P n  after A/D conversion, pdyl n , the second vertical direction component of the position P n  after A/D conversion, pdyr n , the lens coefficient F, and the hall sensor distance coefficient HSD. The hall sensor distance coefficient HSD is the relative distance between the first vertical hall sensor hv 1  and the second vertical hall sensor hv 2  in the first direction x. 
   The AE unit (exposure-calculating unit)  23  performs the photometric operation and calculates the photometric values, based on the subject being photographed. The AE unit  23  also calculates the aperture value and the time length of the exposure operation, with respect to the photometric values, both of which are needed for imaging. The AF unit  24  performs the AF sensing operation and the corresponding focusing operation, both of which are needed for imaging. In the focusing operation, the camera lens  67  is re-positioned along the optical axis in the LX direction. 
   The anti-shake part (the anti-shake apparatus) of the photographing device  1  comprises an anti-shake button  14 , an anti-shake switch  14   a , a display  17 , a CPU  21 , an angular velocity detection unit  25 , a driver circuit  29 , an anti-shake unit  30 , a hall-sensor signal-processing unit  45 , and the camera lens  67 . 
   When the anti-shake button  14  is depressed by the operator, the anti-shake switch  14   a  is changed to the ON state so that the anti-shake operation, in which the angular velocity detection unit  25  and the anti-shake unit  30  are driven independently of the other operations which include the photometric operation etc., is carried out at the predetermined time interval. When the anti-shake switch  14   a  is in the ON state, in other words in the anti-shake mode, the anti-shake parameter SR is set to 1 (IS=1). When the anti-shake switch  14   a  is not in the ON state, in other words in the non-anti-shake mode, the anti-shake parameter SR is set to 0 (IS=0). In the embodiment, the value of the predetermined time interval is set to 1 ms. 
   The various output commands corresponding to the input signals of these switches are controlled by the CPU  21 . 
   The information regarding whether the photometric switch  12   a  is in the ON state or OFF state is input to port P 12  of the CPU  21  as a 1-bit digital signal. The information regarding whether the release switch  13   a  is in the ON state or OFF state is input to port P 13  of the CPU  21  as a 1-bit digital signal. Likewise, the information regarding whether the anti-shake switch  14   a  is in the ON state or OFF state is input to port P 14  of the CPU  21  as a 1-bit digital signal. 
   The AE unit  23  is connected to port P 4  of the CPU  21  for inputting and outputting signals. The AF unit  24  is connected to port P 5  of the CPU  21  for inputting and outputting signals. The display  17  is connected to port P 6  of the CPU  21  for inputting and outputting signals. 
   Next, the details of the input and output relationships between the CPU  21  and the angular velocity detection unit  25 , the driver circuit  29 , the anti-shake unit  30 , and the hall-sensor signal-processing unit  45  are explained. 
   The angular velocity detection unit  25  has a first angular velocity sensor  26   a , a second angular velocity sensor  26   b , a third angular velocity sensor  26   c , a first high-pass filter circuit  27   a , a second high-pass filter circuit  27   b , a third high-pass filter circuit  27   c , a first amplifier  28   a , a second amplifier  28   b , and a third amplifier  28   c.    
   The first angular velocity sensor  26   a  detects the angular velocity of rotary motion of the photographing device  1  about the axis of the second direction y (the yaw). In other words, the first angular velocity sensor  26   a  is a gyro sensor that detects the yaw angular velocity. 
   The second angular velocity sensor  26   b  detects the angular velocity of rotary motion of the photographing device  1  about the axis of the first direction x (the pitch). In other words, the second angular velocity sensor  26   b  is a gyro sensor that detects the pitch angular velocity. 
   The third angular velocity sensor  26   c  detects the angular velocity of rotary motion of the photographing device  1  about the axis of the third direction z (the roll). In other words, the third angular velocity sensor  26   c  is a gyro sensor that detects the roll angular velocity. 
   The first high-pass filter circuit  27   a  reduces the low-frequency component of the signal output from the first angular velocity sensor  26   a , because the low-frequency component of the signal output from the first angular velocity sensor  26   a  includes signal elements that are based on null voltage and panning motion, neither of which are related to hand-shake. 
   Similarly, the second high-pass filter circuit  27   b  reduces the low-frequency component of the signal output from the second angular velocity sensor  26   b , because the low-frequency component of the signal output from the second angular velocity sensor  26   b  includes signal elements that are based on null voltage and panning motion, neither of which are related to hand-shake. 
   Likewise, the third high-pass filter circuit  27   c  reduces the low-frequency component of the signal output from the third angular velocity sensor  26   c , because the low-frequency component of the signal output from the third angular velocity sensor  26   c  includes signal elements that are based on null voltage and panning motion, neither of which are related to hand-shake. 
   The first amplifier  28   a  amplifies the signal representing the yaw angular velocity, whose low-frequency component has been reduced, and outputs the analog signal to the A/D converter A/D  0  of the CPU  21  as a first angular velocity vx. 
   The second amplifier  28   b  amplifies the signal representing the pitch angular velocity, whose low-frequency component has been reduced, and outputs the analog signal to the A/D converter A/D  1  of the CPU  21  as a second angular velocity vy. 
   The third amplifier  28   c  amplifies the signal representing the pitch angular velocity, whose low-frequency component has been reduced, and outputs the analog signal to the A/D converter A/D  2  of the CPU  21  as a third angular velocity vθ. 
   The reduction of the low-frequency component is a two-step process. The primary part of the analog high-pass filter processing operation is performed first by the first, second, and third high-pass filter circuits  27   a ,  27   b , and  27   c , followed by the secondary part of the digital high-pass filter processing operation that is performed by the CPU  21 . 
   The cut-off frequency of the secondary part of the digital high-pass filter processing operation is higher than that of the primary part of the analog high-pass filter processing operation. 
   In the digital high-pass filter processing operation, the value of time constants (a first high-pass filter time constant hx, a second high-pass filter time constant hy, and a third high-pass filter time constant hθ) can be easily changed. 
   The supply of electric power to the CPU  21  and each part of the angular velocity detection unit  25  begins after the PON switch  11   a  is set to the ON state (i.e. when the main power supply is set to the ON state). The calculation of a hand-shake quantity begins after the PON switch  11   a  is set to the ON state. 
   The CPU  21  converts the first angular velocity vx, which is input to the A/D converter A/D  0 , to a first digital angular velocity signal Vx n  (A/D conversion operation). It also calculates a first digital angular velocity VVx n  by reducing the low-frequency component of the first digital angular velocity signal Vx n  (the digital high-pass filter processing operation) because the low-frequency component of the first digital angular velocity signal Vx n  includes signal elements that are based on null voltage and panning motion, neither of which are related to hand-shake. It also calculates a hand shake quantity (a hand-shake displacement angle: a first digital displacement angle Kx n  caused by yaw) by integrating the first digital angular velocity VVx n  (the integration processing operation). 
   Similarly, the CPU  21  converts the second angular velocity vy, which is input to the A/D converter A/D  1 , to a second digital angular velocity signal Vy n  (A/D conversion operation). It also calculates a second digital angular velocity VVy n  by reducing the low-frequency component of the second digital angular velocity signal Vy n  (the digital high-pass filter processing operation) because the low-frequency component of the second digital angular velocity signal Vy n  includes signal elements that are based on null voltage and panning motion, neither of which are related to hand-shake. It also calculates a hand shake quantity (a hand-shake displacement angle: a second digital displacement angle Ky n  caused by pitch) by integrating the second digital angular velocity VVy n  (the integration processing operation). 
   Furthermore, the CPU  21  converts the third angular velocity vθ, which is input to the A/D converter A/D  2 , to a third digital angular velocity signal Vθ n  (A/D conversion operation). It also calculates a third digital angular velocity VVθ n  by reducing the low-frequency component of the third digital angular velocity signal Vθ n  (the digital high-pass filter processing operation) because the low-frequency component of the third digital angular velocity signal Vθ n  includes signal elements that are based on null voltage and panning motion, neither of which are related to hand-shake. It also calculates a hand shake quantity (a hand-shake displacement angle: a third digital displacement angle Kθ n  caused by roll) by integrating the third digital angular velocity VVθ n  (the integration processing operation). 
   Accordingly, the CPU  21  and the angular velocity detection unit  25  have a function for calculating the hand-shake quantity. 
   The value “n” is an integer that is greater than 0, and indicates a length of time (ms) from the point when the interrupt process of the timer commences, (t=0, and see step S 12  in  FIG. 4 ) to the point when the last anti-shake operation was performed (t=n). 
   In the digital high-pass filter processing operation regarding the yaw, the first digital angular velocity VVx n  is calculated by dividing the sum of the first digital angular velocity VVx 0  and VVx n-1  (calculated by the interrupt process of the timer before the 1 ms predetermined time interval, before the last anti-shake operation was performed), by the first high-pass filter time constant hx, and then subtracting the resulting quotient from the first digital angular velocity signal Vx n  (VVx n =Vx n −(ΣVVx n-1 )÷hx, see ( 1 ) in  FIG. 6 ). 
   In the digital high-pass filter processing operation regarding the pitch, the second digital angular velocity VVy n  is calculated by dividing the sum of the second digital angular velocity VVy 0  and VVy n-1  (calculated by the interrupt process of the timer before the 1 ms predetermined time interval, before the last anti-shake operation was performed), by the second high-pass filter time constant hy, and then subtracting the resulting quotient from the second digital angular velocity signal Vy n  (VVy n =Vy n-1 (ΣVVy n-1 )÷hy). 
   In the digital high-pass filter processing operation regarding the roll, the third digital angular velocity VVθ n  is calculated by dividing the sum of the third digital angular velocity VVθ 0  and VVθ n-1  (calculated by the interrupt process of the timer before the 1 ms predetermined time interval, before the last anti-shake operation was performed), by the third high-pass filter time constant hθ, and then subtracting the resulting quotient from the third digital angular velocity signal Vθ n  (VVθ n =Vθ n −(ΣVVθ n-1 )÷hθ). 
   In the embodiment, the angular velocity detection operation during (a portion of) the interrupt process of the timer includes a process in the angular velocity detection unit  25  and a process of inputting process of the first, second, and third angular velocities vx, vy, and vθ from the angular velocity detection unit  25  to the CPU  21 . 
   In the integration processing operation regarding the yaw, the first digital displacement angle Kx n  is calculated by summing the first digital angular velocity VVx 0  at the point when the interrupt process of the timer commences, t=0, (see step S 12  in  FIG. 4 ) and the first digital angular velocity VVx n  at the point when the last anti-shake operation was performed (t=n), (Kx n =ΣVVx n , see ( 7 ) in  FIG. 6 ). 
   Similarly, in the integration processing operation regarding the pitch, the second digital displacement angle Ky n  is calculated by summing the second digital angular velocity VVy 0  at the point when the interrupt process of the timer commences and the second digital angular velocity VVy n  at the point when the last anti-shake operation was performed (Ky n =ΣVVy n , see ( 7 ) in  FIG. 6 ). 
   Further, in the integration processing operation regarding the roll, the third digital displacement angle Kθ n  is calculated by summing the third digital angular velocity VVθ 0  at the point when the interrupt process of the timer commences and the third digital angular velocity VVθ n  at the point when the last anti-shake operation was performed (Kθ n =ΣVVθ n , see ( 8 ) in  FIG. 6 ). 
   The CPU  21  calculates the position S n  where the imaging unit  39   a  (the movable unit  30   a ) should be moved, corresponding to the hand-shake quantity (the first, second, and third digital displacement angles Kx n , Ky n , and Kθ n ) calculated for the first direction x, the second direction y, and the rotational direction, based on the lens coefficient F and the hall sensor distance coefficient HSD (Sx n =F×tan(Kx n ), Sy n =F×tan(Ky n ), Sθ n =HSD÷2×sin(Kθ n ), see ( 3 ) in  FIG. 6 ). In this calculation, not only the linear movement of the movable unit  30   a  on the xy plane but also the rotation of the movable unit  30   a  on the xy plane is considered. 
   The horizontal direction component of the position S n  is defined as Sx n , the vertical direction component of the position S n  is defined as Sy n , and the rotational (inclination) direction component of the position S n  is defined as Sθ n . 
   The rotation of the movable unit  30   a  is performed by applying different forces in the second direction y on a first driving point and a second driving point on the movable unit  30   a . The movement of the movable unit  30   a  in the second direction y is performed by applying the same driving forces in the second direction y on the first and second driving points on the movable unit  30   a . The first driving point is the point to which a first vertical electro-magnetic force based on the first vertical coil  32   a   1  is applied. The second driving point is the point to which a second vertical electro-magnetic force based on the second vertical coil  32   a   2  is applied. The first driving point is set to a position close to the first vertical hall sensor hv 1 . The second driving point is set to a position close to the second vertical hall sensor hv 2 . 
   The first vertical direction component of the first driving point corresponding to the position S n  is defined as Syl n . The second vertical direction component of the second driving point corresponding to the position S n  is defined as Syr n . 
   The first vertical direction component of the first driving point, Syl n , and the second vertical direction component of the second driving point, Syr n , are calculated on the basis of the vertical direction component of the position S n , Sy n , and the rotational direction component of the position S n , Sθ n , (Syl n =Sy n +Sθ n , Syr n =Sy n −Sθ n , see ( 4 ) in  FIG. 6 ). 
   The calculations of the first digital displacement angle Kx n , the second digital displacement angle Ky n , the horizontal direction component of the position S n , Sx n , the vertical direction component of the position S n , Sy n , the first vertical direction component of the first driving point, Syl n , and the second vertical direction component of the second driving point, Syr n  are performed only during the first period, under the condition where the anti-shake parameter SR is set to 1 (see steps S 61 , S 63 , and S 64  of  FIG. 5 ). 
   The first period commences when the mirror-up operation is finished; in other words, when the value of the mirror state parameter MP has changed from 1 to 0 after the release button  13  is fully depressed so that the release switch  13   a  is set to the ON state. 
   The first period is finished when the release sequence is finished; in other words, when the value of the release-state parameter RP has changed from 1 to 0. 
   In sum, the calculations of the first digital displacement angle Kx n , the second digital displacement angle Ky n , the horizontal direction component of the position S n , Sx n , the vertical direction component of the position S n , Sy n , the first vertical direction component of the first driving point, Syl n , and the second vertical direction component of the second driving point, Syr n  commence immediately before the shutter is opened and the exposure operation commences. Therefore, in the embodiment, the movement of the movable unit  30   a  commences in accordance with the calculations of the first digital displacement angle Kx n  etc., immediately before the shutter is opened and the exposure operation commences. 
   On the other hand, a parallax may arise between the position of the movable unit including the imaging device  39   a   1  at the time point when the release button  13  is fully depressed and the position of the movable unit including the imaging device  39   a   1  at the time point when the exposure operation commences, if the movement of the movable unit  30   a  commences immediately after the release button  13  is fully depressed. 
   However, in the embodiment, this parallax can be reduced, because the movable unit  30   a  is not moved until the mirror-up operation is finished immediately before the commencement of the exposure operation. 
   The calculation of the third digital displacement angle Kθ n  is performed after the release switch  13   a  is set to the ON state. Therefore, the timing of the commencement of the calculation of the third digital displacement angle Kθ n  does not relate to the mirror-up operation. In other words, it does not relate to the value of the mirror state parameter MP (see steps S 56  and S 61  of  FIG. 5 ). However, when the photographing device  1  is in the non-anti-shake mode, the calculation of the third digital displacement angle Kθ n  is not performed after the completion of the mirror-up operation (see step S 60  of  FIG. 5 ). 
   The calculation of the rotational direction component of the position S n , Sθ n , is performed after the release switch  13   a  is set to the ON state. Therefore, the timing of the commencement of the position S n , Sθ n , does not relate to the mirror-up operation. In other words, it does not relate to the value of the mirror state parameter MP (see steps S 57  and S 64  of  FIG. 5 ). However, when the photographing device  1  is in the non-anti-shake mode, the calculation of the rotational direction component of the position S n , Sθ n , is not performed after the completion of the mirror-up operation (see step S 60  of  FIG. 5 ). 
   While the full depression of the release button  13  for activating the ON state of the release switch  13   a  and the mirror-up operation are performed, in other words, during a second period from when the release button  13  is fully depressed to when the exposure operation commences, the hand-shake caused by roll tends to occur, in other words, the hand-shake angle caused by roll (the third digital displacement angle Kθ n ) tends to increase (see time points t 2  to t 4  of  FIG. 8 ). 
   In the embodiment, because the hand-shake caused by roll in the second period, in which the hand-shake caused by roll tends to occur, is considered for the anti-shake operation, the hand-shake quantity, in particular, the hand-shake angle caused by roll, that is, the third digital displacement angle Kθ n , can be accurately calculated. 
   The hand-shake caused by roll influences the rotation of the movable unit  30   a  in the anti-shake operation, but does not influence the linear movement of the movable unit  30   a  in the anti-shake operation. The rotation of the movable unit  30   a  in the anti-shake operation does not affect the parallax. 
   However, the calculation of the rotational direction component of the position S n , Sθ n , is not performed when the value of the lens resolution parameter RMTF is 0, even if the photographing device  1  is in the anti-shake mode. This is because the resolution at the edge of the camera lens  67  is low, so that the result of the anti-shake operation for correcting hand-shake caused by roll is ineffective, in other words, the effect of the anti-shake operation for correcting hand-shake caused by roll can not be visually confirmed. Moreover, correcting for roll would reduce the range of movement of the movable unit  30   a  for correcting hand-shake caused by pitch and yaw. 
   The movement of the movable unit  30   a , which includes the imaging unit  39   a , is performed by using an electro-magnetic force and is described later. 
   The driving force D n  is for driving the driver circuit  29  in order to move the movable unit  30   a  to the position S n . 
   The horizontal direction component of the driving force D n  for the first and second horizontal coils  31   a   1  and  31   a   2  is defined as the horizontal driving force Dx n  (after D/A conversion, the horizontal PWM duty dx). 
   The vertical direction component of the driving force D n  for the first vertical coil  32   a   1  is defined as the first vertical driving force Dyl n  (after D/A conversion, the first vertical PWM duty dyl). 
   The vertical direction component of the driving force D n  for the second vertical coil  32   a   2  is defined as the second vertical driving force Dyr n  (after D/A conversion, the second vertical PWM duty dyr). 
   The anti-shake unit  30  is an apparatus that corrects for effects of hand-shake by moving and rotating the imaging unit  39   a  to the position S n , by canceling the lag of the photographing subject image on the imaging surface of the imaging device  39   a   1  of the imaging unit  39   a , and by stabilizing the photographing subject image displayed on the imaging surface of the imaging device  39   a   1 , during the first period including the exposure time and when the anti-shake operation is performed (i.e., SR=1). 
   The anti-shake unit  30  has a fixed unit  30   b  and a movable unit  30   a  which includes the imaging unit  39   a  and can be moved about on the xy plane. 
   During the first period and when the anti-shake operation is not performed (i.e., SR=0), the movable unit  30   a  is fixed to (held at) a predetermined position. In the embodiment, this predetermined position is at the center of the range of movement. 
   The driving of the movable unit  30   a  of the anti-shake unit  30 , including movement to a predetermined fixed (held) position, is performed by the electro-magnetic force of the coil unit and the magnetic unit, through the driver circuit  29  which has the horizontal PWM duty dx input from the PWM  0  of the CPU  21 , the first vertical PWM duty dyl input from the PWM  1  of the CPU  21 , and the second vertical PWM duty dyr input from the PWM  2  of the CPU  21  (see ( 6 ) in  FIG. 6 ). 
   The detected-position P n  of the movable unit  30   a , either before or after the movement effected by the driver circuit  29 , is detected by the hall sensor unit  44   a  and the hall-sensor signal-processing unit  45 . 
   Information regarding the horizontal direction component of the detected-position P n , in other words, the horizontal detected-position signal px, is input to the A/D converter A/D  3  of the CPU  21  (see ( 2 ) in  FIG. 6 ). The horizontal detected-position signal px is an analog signal that is converted to a digital signal by the A/D converter A/D  3  (A/D conversion operation). The horizontal direction component of the detected-position P n  after the A/D conversion operation, is defined as pdx n  and corresponds to the horizontal detected-position signal px. 
   Information regarding one of the vertical direction components of the detected-position P n , in other words, the first vertical detected-position signal pyl, is input to the A/D converter A/D  4  of the CPU  21 . The first vertical detected-position signal pyl is an analog signal that is converted to a digital signal by the A/D converter A/D  4  (A/D conversion operation). The first vertical direction component of the detected-position P n  after the A/D conversion operation is defined as pdyl n  and corresponds to the first vertical detected-position signal pyl. 
   Information regarding the other of the vertical direction components of the detected-position P n , in other words, the second vertical detected-position signal pyr, is input to the A/D converter A/D  5  of the CPU  21 . The second vertical detected-position signal pyr is an analog signal that is converted to a digital signal by the A/D converter A/D  5  (A/D conversion operation). The second vertical direction component of the detected-position P n  after the A/D conversion operation is defined as pdyr n  and corresponds to the second vertical detected-position signal pyr. 
   The PID (Proportional Integral Differential) control calculates the horizontal driving force Dx n  and the first and second vertical driving forces Dyl n  and Dyr n  on the basis of the coordinate data for the detected-position P n  (pdx n , pdyl n , pdyr n ) and the position S n  (Sx n , Syl n , Syr n ) following movement (see ( 5 ) in  FIG. 6 ). 
   Driving of the movable unit  30   a  to the position S n , (Sx n , Syl n , Syr n ) corresponding to the anti-shake operation of the PID control, is performed when the photographing device  1  is in the anti-shake mode (SR=1), when the anti-shake switch  14   a  is set to the ON state, and during the first period including the exposure time. 
   During the mirror-up operation from when the value of the mirror state parameter MP is set to 1, to when the value of the mirror state parameter MP is changed from 1 to 0, PID control unrelated to the anti-shake operation is performed so that the movable unit  30   a  is moved to the center of the range of movement (the predetermined position) such that the four sides that compose the outline of the imaging surface of the imaging device  39   a   1  of the imaging unit  39   a  are parallel to the first direction x or the second direction y, in other words, that the movable unit  30   a  is not rotated (inclined). 
   When the anti-shake parameter SR is 0 and during the first period including the exposure time, PID control unrelated to the anti-shake operation is performed so that the movable unit  30   a  is moved to the center of the range of movement (the predetermined position) such that the four sides that compose the outline of the imaging surface of the imaging device  39   a   1  of the imaging unit  39   a  are parallel to the first direction x or the second direction y, in other words, that the movable unit  30   a  is not rotated (inclined). 
   Except for the period during the mirror-up operation and the first period, the movable unit  30   a  is not driven (moved). 
   The movable unit  30   a  has a coil unit for driving that is comprised of a first horizontal coil  31   a   1 , a second horizontal coil  31   a   2 , a first vertical coil  32   a   1 , and a second vertical coil  32   a   2 , an imaging unit  39   a  having the imaging device  39   a   1 , and a hall sensor unit  44   a  as a magnetic-field change-detecting element unit. In the embodiment, the imaging device  39   a   1  is a CCD; however, the imaging device  39   a   1  may be of another type, such as a CMOS, etc. 
   The fixed unit  30   b  has a magnetic driving unit that is comprised of a first horizontal magnet  411   b   1 , a second horizontal magnet  411   b   2 , a first vertical magnet  412   b   1 , a second vertical magnet  412   b   2 , a first horizontal yoke  431   b   1 , a second horizontal yoke  431   b   2 , a first vertical yoke  432   b   1 , and a second vertical yoke  432   b   2 . 
   The fixed unit  30   b  movably and rotatably supports the movable unit  30   a  in the range of movement on the xy plane, using balls, etc. 
   When the center area of the imaging device  39   a   1  is intersected by the optical axis LX of the camera lens  67 , the relationship between the position of the movable unit  30   a  and the position of the fixed unit  30   b  is arranged so that the movable unit  30   a  is positioned at the center of its range of movement in both the first direction x and the second direction y, in order to utilize the full size of the imaging range of the imaging device  39   a   1 . 
   The rectangular form of the imaging surface of the imaging device  39   a   1  has two diagonal lines. In the embodiment, the center of the imaging device  39   a   1  is at the intersection of these two diagonal lines. 
   Furthermore, the movable unit  30   a  is positioned at the center of its range of movement in both the first direction x and the second direction y, and the four sides that compose the outline of the imaging surface of the imaging device  39   a   1  are parallel to the first direction x or the second direction y, in an initial state immediately after the release switch  13   a  is set to the ON state (see step S 58  of  FIG. 5 ). 
   The first horizontal coil  31   a   1 , the second horizontal coil  31   a   2 , the first vertical coil  32   a   1 , the second vertical coil  32   a   2 , and the hall sensor unit  44   a  are attached to the movable unit  30   a.    
   The first horizontal coil  31   a   1  forms a seat and a spiral-shaped coil pattern. The coil pattern of the first horizontal coil  31   a   1  has lines which are parallel to the second direction y, thus creating the first horizontal electro-magnetic force to move the movable unit  30   a  that includes the first horizontal coil  31   a   1 , in the first direction x. 
   The first horizontal electro-magnetic force is created by the current direction of the first horizontal coil  31   a   1  and the magnetic-field direction of the first horizontal magnet  411   b   1 . 
   The second horizontal coil  31   a   2  forms a seat and a spiral-shaped coil pattern. The coil pattern of the second horizontal coil  31   a   2  has lines which are parallel to the second direction y, thus creating the second horizontal electro-magnetic force to move the movable unit  30   a  that includes the second horizontal coil  31   a   2 , in the first direction x. 
   The second horizontal electro-magnetic force is created by the current direction of the second horizontal coil  31   a   2  and the magnetic-field direction of the second horizontal magnet  411   b   2 . 
   The first vertical coil  32   a   1  forms a seat and a spiral-shaped coil pattern. The coil pattern of the first vertical coil  32   a   1  has lines which are parallel to the first direction x, thus creating the first vertical electro-magnetic force to move the movable unit  30   a  that includes the first vertical coil  32   a   1 , in the second direction y and to rotate the movable unit  30   a.    
   The first vertical electro-magnetic force is created by the current direction of the first vertical coil  32   a   1  and the magnetic-field direction of the first vertical magnet  412   b   1 . 
   The second vertical coil  32   a   2  forms a seat and a spiral-shaped coil pattern. The coil pattern of the second vertical coil  32   a   2  has lines which are parallel to the first direction x, thus creating the second vertical electro-magnetic force to move the movable unit  30   a  that includes the second vertical coil  32   a   2 , in the second direction y and to rotate the movable unit  30   a.    
   The second vertical electro-magnetic force is created by the current direction of the second vertical coil  32   a   2  and the magnetic-field direction of the second vertical magnet  412   b   2 . 
   The first and second horizontal coils  31   a   1  and  31   a   2  and the first and second vertical coils  32   a   1  and  32   a   2  are connected to the driver circuit  29 , which drives the first and second horizontal coils  31   a   1  and  31   a   2  and the first and second vertical coils  32   a   1  and  32   a   2 , through the flexible circuit board (not depicted). 
   The horizontal PWM duty dx, that is a duty ratio of a PWM pulse, is input to the driver circuit  29  from the PWM  0  of the CPU  21 . The first vertical PWM duty dyl, that is a duty ratio of a PWM pulse, is input to the driver circuit  29  from the PWM  1  of the CPU  21 . The second vertical PWM duty dyr, that is a duty ratio of a PWM pulse, is input to the driver circuit  29  from the PWM  2  of the CPU  21 . 
   The driver circuit  29  supplies the same power to the first and second horizontal coils  31   a   1  and  31   a   2 , corresponding to the value of the horizontal PWM duty dx, to move the movable unit  30   a  in the first direction x. 
   The driver circuit  29  supplies power to the first vertical coil  32   a   1  corresponding to the value of the first vertical PWM duty dyl and to the second vertical coil  32   a   2  corresponding to the value of the second vertical PWM duty dyr, in order to move the movable unit  30   a  in the second direction y and to rotate the movable unit  30   a.    
   The positional relationship between the first and second horizontal coils  31   a   1  and  31   a   2  is determined so that the optical axis LX is located between the first and second horizontal coils  31   a   1  and  31   a   2  in the first direction x, in the initial state. In other words, the first and second horizontal coils  31   a   1  and  31   a   2  are arranged in a symmetrical position centered on the optical axis LX, in the first direction x in the initial state. 
   The first and second vertical coils  32   a   1  and  32   a   2  are arranged in the first direction x in the initial state. 
   The first and second horizontal coils  31   a   1  and  31   a   2  are arranged such that the distance between the center of the imaging device  39   a   1  and the center area of the first horizontal coil  31   a   1  in the first direction x is the same as the distance between the center of the imaging device  39   a   1  and the center area of the second horizontal coil  31   a   2  in the first direction x. 
   The first and second vertical coils  32   a   1  and  32   a   2  are arranged such that in the initial state, the distance between the center of the imaging device  39   a   1  and the center area of the first vertical coil  32   a   1  in the second direction y is the same as the distance between the center of the imaging device  39   a   1  and the center area of the second vertical coil  32   a   2  in the second direction y. 
   The first horizontal magnet  411   b   1  is attached to the movable unit side of the fixed unit  30   b , where the first horizontal magnet  411   b   1  faces the first horizontal coil  31   a   1  and the horizontal hall sensor hh 10  in the third direction z. 
   The second horizontal magnet  411   b   2  is attached to the movable unit side of the fixed unit  30   b , where the second horizontal magnet  411   b   2  faces the second horizontal coil  31   a   2  in the third direction z. 
   The first vertical magnet  412   b   1  is attached to the movable unit side of the fixed unit  30   b , where the first vertical magnet  412   b   1  faces the first vertical coil  32   a   1  and the first vertical hall sensor hv 1  in the third direction z. 
   The second vertical magnet  412   b   2  is attached to the movable unit side of the fixed unit  30   b , where the second vertical magnet  412   b   2  faces the second vertical coil  32   a   2  and the second vertical hall sensor hv 2  in the third direction z. 
   The first horizontal magnet  411   b   1  is attached to the first horizontal yoke  431   b   1 , such that the N pole and S pole are arranged in the first direction x. The first horizontal yoke  431   b   1  is attached to the fixed unit  30   b , on the side of the movable unit  30   a , in the third direction z. 
   Likewise, the second horizontal magnet  411   b   2  is attached to the second horizontal yoke  431   b   2 , such that the N pole and S pole are arranged in the first direction x. The second horizontal yoke  431   b   2  is attached to the fixed unit  30   b , on the side of the movable unit  30   a , in the third direction z. 
   The first vertical magnet  412   b   1  is attached to the first vertical yoke  432   b   1 , such that the N pole and S pole are arranged in the second direction y. The first vertical yoke  432   b   1  is attached to the fixed unit  30   b , on the side of the movable unit  30   a , in the third direction z. 
   Likewise, the second vertical magnet  412   b   2  is attached to the second vertical yoke  432   b   2 , such that the N pole and S pole are arranged in the second direction y. The second vertical yoke  432   b   2  is attached to the fixed unit  30   b , on the side of the movable unit  30   a , in the third direction z. 
   The first and second horizontal yokes  431   b   1  and  431   b   2  are made of a soft magnetic material. 
   The first horizontal yoke  431   b   1  prevents the magnetic-field of the first horizontal magnet  411   b   1  from dissipating to the surroundings, and raises the magnetic-flux density between the first horizontal magnet  411   b   1  and the first horizontal coil  31   a   1 , and between the first horizontal magnet  411   b   1  and the horizontal hall sensor hh 10 . 
   Similarly, the second horizontal yoke  431   b   2  prevents the magnetic-field of the second horizontal magnet  411   b   2  from dissipating to the surroundings, and raises the magnetic-flux density between the second horizontal magnet  411   b   2  and the second horizontal coil  31   a   2 . 
   The first and second vertical yokes  432   b   1  and  432   b   2  are made of a soft magnetic material. 
   The first vertical yoke  432   b   1  prevents the magnetic-field of the first vertical magnet  412   b   1  from dissipating to the surroundings, and raises the magnetic-flux density between the first vertical magnet  412   b   1  and the first vertical coil  32   a   1 , and between the first vertical magnet  412   b   1  and the first vertical hall sensor hv 1 . 
   Likewise, the second vertical yoke  432   b   2  prevents the magnetic-field of the second vertical magnet  412   b   2  from dissipating to the surroundings, and raises the magnetic-flux density between the second vertical magnet  412   b   2  and the second vertical coil  32   a   2 , and between the second vertical magnet  412   b   2  and the second vertical hall sensor hv 2 . 
   The first and second horizontal yokes  431   b   1  and  431   b   2  and the first and second vertical yokes  432   b   1  and  432   b   2  may be composed of one body or separate bodies. 
   The hall sensor unit  44   a  is a one-axis hall sensor with three component hall sensors that are magnetoelectric converting elements (magnetic-field change-detecting elements) using the Hall Effect. The hall sensor unit  44   a  detects the horizontal detected-position signal px, the first vertical detected-position signal pyl, and the second vertical detected-position signal pyr. 
   One of the three hall sensors is a horizontal hall sensor hh 10  for detecting the horizontal detected-position signal px, and another of the three hall sensors is a first vertical hall sensor hv 1  for detecting the first vertical detected-position signal pyl, with the third being a second vertical hall sensor hv 2  for detecting the second vertical detected-position signal pyr. 
   The horizontal hall sensor hh 10  is attached to the movable unit  30   a , where the horizontal hall sensor hh 10  faces the first horizontal magnet  411   b   1  of the fixed unit  30   b  in the third direction z. 
   The horizontal hall sensor hh 10  may be arranged outside the spiral shape of the winding of the first horizontal coil  31   a   1  in the second direction y. However, it is desirable for the horizontal hall sensor hh 10  to be arranged inside the spiral shape of the winding of the first horizontal coil  31   a   1 , midway along the outer circumference of the spiral shape of the winding of the first horizontal coil  31   a   1  in the first direction x (see  FIG. 7 ). 
   The horizontal hall sensor hh 10  is layered on the first horizontal coil  31   a   1  in the third direction z. Accordingly, the area in which the magnetic-field is generated for the position-detecting operation and the area in which the magnetic-field is generated for driving the movable unit  30   a  are shared. Therefore, the length of the first horizontal magnet  411   b   1  in the second direction y and the length of the first horizontal yoke  431   b   1  in the second direction y can be shortened. 
   The first vertical hall sensor hv 1  is attached to the movable unit  30   a , where the first vertical hall sensor hv 1  faces the first vertical magnet  412   b   1  of the fixed unit  30   b  in the third direction z. 
   The second vertical hall sensor hv 2  is attached to the movable unit  30   a , where the second vertical hall sensor hv 2  faces the second vertical magnet  412   b   2  of the fixed unit  30   b  in the third direction z. 
   Similarly, the first vertical hall sensor hv 1  may be arranged outside the spiral shape of the winding of the first vertical coil  32   a   1  in the first direction x. However, it is desirable for the first vertical hall sensor hv 1  to be arranged inside the spiral shape of the winding of the first vertical coil  32   a   1 , midway along the outer circumference of the spiral shape of the winding of the first vertical coil  32   a   1  in the second direction y. 
   The first vertical hall sensor hv 1  is layered on the first vertical coil  32   a   1  in the third direction z. Accordingly, the area in which the magnetic-field is generated for the position-detecting operation and the area in which the magnetic-field is generated for driving the movable unit  30   a  are shared. Therefore, the length of the first vertical magnet  412   b   1  in the first direction x and the length of the first vertical yoke  432   b   1  in the first direction x can be shortened. 
   The second vertical hall sensor hv 2  may be arranged outside the spiral shape of the winding of the second vertical coil  32   a   2  in the first direction x. However, it is desirable for the second vertical hall sensor hv 2  to be arranged inside the spiral shape of the winding of the second vertical coil  32   a   2 , midway along the outer circumference of the spiral shape of the winding of the second vertical coil  32   a   2  in the second direction y. 
   The second vertical hall sensor hv 2  is layered on the second vertical coil  32   a   2  in the third direction z. Accordingly, the area in which the magnetic-field is generated for the position-detecting operation and the area in which the magnetic-field is generated for driving the movable unit  30   a  are shared. Therefore, the length of the second vertical magnet  412   b   2  in the first direction x and the length of the second vertical yoke  432   b   2  in the first direction x can be shortened. 
   Furthermore, the first driving point to which the first vertical electro-magnetic force based on the first vertical coil  32   a   1  is applied can be close to a position-detecting point by the first vertical hall sensor hv 1 , and the second driving point to which the second vertical electro-magnetic force based on the second vertical coil  32   a   2  is applied can be close to a position-detecting point by the second vertical hall sensor hv 2 . Therefore, accurate driving control of the movable unit  30   a  can be performed. 
   In the initial state, it is desirable for the horizontal hall sensor hh 10  to be located at a place on the hall sensor unit  44   a  which faces an intermediate area between the N pole and S pole of the first horizontal magnet  411   b   1  in the first direction x, as viewed from the third direction z, to perform the position-detecting operation utilizing the full range within which an accurate position-detecting operation can be performed based on the linear output change (linearity) of the one-axis hall sensor. 
   Similarly, in the initial state, it is desirable for the first vertical hall sensor hv 1  to be located at a place on the hall sensor unit  44   a  which faces an intermediate area between the N pole and S pole of the first vertical magnet  412   b   1  in the second direction y, as viewed from the third direction z. 
   Likewise, in the initial state, it is desirable for the second vertical hall sensor hv 2  to be located at a place on the hall sensor unit  44   a  which faces an intermediate area between the N pole and S pole of the second vertical magnet  412   b   2  in the second direction y, as viewed from the third direction z. 
   The first hall-sensor signal-processing unit  45  has a first hall-sensor signal-processing circuit  450  and a second hall-sensor signal-processing circuit  460  and a third hall-sensor signal-processing circuit  470 . 
   The first hall-sensor signal-processing circuit  450  detects a horizontal potential difference between the output terminals of the horizontal hall sensor hh 10 , based on the output signal of the horizontal hall sensor hh 10 . 
   The first hall-sensor signal-processing circuit  450  outputs the horizontal detected-position signal px to the A/D converter A/D  3  of the CPU  21 , on the basis of the horizontal potential difference. The horizontal detected-position signal px represents the location of the part of the movable unit  30   a  which has the horizontal hall sensor hh 10 , in the first direction x. 
   The first hall-sensor signal-processing circuit  450  is connected to the horizontal hall sensor hh 10  through the flexible circuit board (not depicted). 
   The second hall-sensor signal-processing circuit  460  detects a first vertical potential difference between the output terminals of the first vertical hall sensor hv 1 , based on the output signal of the first vertical hall sensor hv 1 . 
   The second hall-sensor signal-processing circuit  460  outputs the first vertical detected-position signal pyl to the A/D converter A/D  4  of the CPU  21 , on the basis of the first vertical potential difference. The first vertical detected-position signal pyl represents the location of the part of the movable unit  30   a  which has the first vertical hall sensor hv 1  (the position-detecting point by the first vertical hall sensor hv 1 ), in the second direction y. 
   The second hall-sensor signal-processing circuit  460  is connected to the first vertical hall sensor hv 1  through the flexible circuit board (not depicted). 
   The third hall-sensor signal-processing circuit  470  detects a second vertical potential difference between the output terminals of the second vertical hall sensor hv 2 , based on the output signal of the second vertical hall sensor hv 2 . 
   The third hall-sensor signal-processing circuit  470  outputs the second vertical detected-position signal pyr to the A/D converter A/D  5  of the CPU  21 , on the basis of the second vertical potential difference. The second vertical detected-position signal pyr represents the location of the part of the movable unit  30   a  which has the second vertical hall sensor hv 2  (the position-detecting point by the second vertical hall sensor hv 2 ), in the second direction y. 
   The third hall-sensor signal-processing circuit  470  is connected to the second vertical hall sensor hv 2  through the flexible circuit board (not depicted). 
   In the embodiment, the three hall sensors (hh 10 , hv 1  and hv 2 ) are used for specifying the location of the movable unit  30   a  including the rotational angle. 
   The locations in the second direction y of the two points on the movable unit  30   a  are determined by using two of the three hall sensors (hv 1  and hv 2 ). The location in the first direction x of the one point on the movable unit  30   a  is determined by using another of the three hall sensors (hh 10 ). The location of the movable unit  30   a  which includes the rotational angle on the xy plane, can be determined on the basis of the information regarding the locations in the first direction x of the one point and the location in the second direction y of the two points. 
   Next, the main operation of the photographing device  1  in the embodiment is explained using the flowchart of  FIG. 4 . 
   When the PON switch  11   a  is set to the ON state, the electrical power is supplied to the angular velocity detection unit  25  so that the angular velocity detection unit  25  is set to the ON state in step S 11 . 
   In step S 12 , the interrupt process of the timer at the predetermined time interval (1 ms) commences. In step S 13 , the value of the release-state parameter RP is set to 0 (see time point t 0  of  FIG. 8 ). The details of the interrupt process of the timer in the embodiment are explained later using the flowchart of  FIG. 5 . 
   In step S 14 , it is determined whether the photometric switch  12   a  is set to the ON state. When it is determined that the photometric switch  12   a  is not set to the ON state, the operation returns to step S 14  and the process in step S 14  is repeated. Otherwise, the operation continues on to step S 15  (see time points t 1  and t 7  of  FIG. 8 ). 
   In step S 15 , it is determined whether the anti-shake switch  14   a  is set to the ON state. When it is determined that the anti-shake switch  14   a  is not set to the ON state, the value of the anti-shake parameter SR is set to 0 in step S 16 . Otherwise, the value of the anti-shake parameter SR is set to 1 in step S 17 . 
   In step S 18 , the AE sensor of the AE unit  23  is driven, the photometric operation is performed, and the aperture value and the time length of the exposure operation are calculated. 
   The AF sensor and the lens control circuit of the AF unit  24  are driven to perform the AF sensing and focus operations, respectively. 
   In step S 19 , the lens information including the resolution at the edge of the camera lens  67  and the lens coefficient F is communicated from the camera lens  67  to the CPU  21 . 
   The value of the lens resolution parameter RMTF is set to 1 when the value of the resolution at the edge of the camera lens  67  is greater than the threshold value. 
   The value of the lens resolution parameter RMTF is set to 0 when the value of the resolution at the edge of the camera lens  67  is not greater than the threshold value. 
   In step S 20 , it is determined whether the release switch  13   a  is set to the ON state. When the release switch  13   a  is not set to the ON state, the operation returns to step S 14  and the process in steps S 14  to S 19  is repeated. Otherwise, the operation continues on to step S 21 , and then the release sequence operation commences. 
   In step S 21 , the value of the release-state parameter RP is set to 1. In step S 22 , the value of the mirror state parameter MP is set to 1 (see time points t 2  and t 8  of  FIG. 8 ). 
   In step S 23 , the mirror-up operation and the aperture closing operation corresponding to the aperture value that is either preset or calculated, are performed by the mirror-aperture-shutter unit  18 . 
   After the mirror-up operation is finished, the value of the mirror state parameter MP is set to 0 (see time point t 3  of  FIG. 8 ), in step S 24 . In step S 25 , the opening operation of the shutter (the movement of the front curtain of the shutter) commences (see time point t 4  of  FIG. 8 ). 
   In step S 26 , the exposure operation, that is, the electric charge accumulation of the imaging device  39   a   1  (CCD etc.), is performed. After the exposure time has elapsed, the closing operation of the shutter (the movement of the rear curtain in the shutter), the mirror-down operation, and the opening operation of the aperture are performed by the mirror-aperture-shutter unit  18 , in step S 27  (see time point t 5  of  FIG. 8 ). 
   In step S 28 , the electric charge accumulated in the imaging device  39   a   1  during the exposure time is read. In step S 29 , the CPU  21  communicates with the DSP  19  so that the image-processing operation is performed based on the electric charge read from the imaging device  39   a   1 . The image, on which the image-processing operation is performed, is stored in the memory of the photographing device  1 . In step S 30 , the image stored in the memory is displayed on the display  17 . In step S 31 , the value of the release-state parameter RP is set to 0 so that the photometric switch  12   a  and the release switch  13   a  are set to the OFF state and the release sequence operation is finished, and the operation then returns to step S 14 . In other words, the photographing device  1  is returned to a state in which the next imaging operation can be performed (see time point t 6  of  FIG. 8 ). 
   Next, the interrupt process of the timer in the embodiment, which commences in step S 12  in  FIG. 4  and is performed at every predetermined time interval (1 ms) independent of the other operations, is explained using the flowchart of  FIG. 5 . 
   When the interrupt process of the timer commences, the first angular velocity vx, which is output from the angular velocity detection unit  25 , is input to the A/D converter A/D  0  of the CPU  21  and converted to the first digital angular velocity signal Vx n , in step S 51 . The second angular velocity vy, which is also output from the angular velocity detection unit  25 , is input to the A/D converter A/D  1  of the CPU  21  and converted to the second digital angular velocity signal Vy n . Similarly, the third angular velocity vθ, which is also output from the angular velocity detection unit  25 , is input to the A/D converter A/D  2  of the CPU  21  and converted to the third digital angular velocity signal Vθ n  (the angular velocity detection operation). 
   The low frequencies of the first, second, and third digital angular velocity signals Vx n , Vy n , and Vθ n  are reduced in the digital high-pass filter processing operation (the first, second, and third digital angular velocities VVx n , VVy n , and VVθ n , see ( 1 ) in  FIG. 6 ). 
   In step S 52 , it is determined whether the value of the release-state parameter RP is set to 1. When it is determined that the value of the release-state parameter RP is not set to 1, driving the movable unit  30   a  is set to the OFF state, in other words, the anti-shake unit  30  is set to a state where the driving control of the movable unit  30   a  is not performed in step S 53 . Otherwise, the operation proceeds directly to step S 54 . 
   Therefore, during the period from the time point t 0  of  FIG. 8  to the time point t 2  of  FIG. 8 , the period from the time point t 6  of  FIG. 8  to the time point t 7  of  FIG. 8 , and the period from the time point t 7  of  FIG. 8  to the time point t 8  of  FIG. 8 , the movable unit  30   a  is not driven. In stead, during these periods, the calculations of the first, second, and third digital angular velocity VVx n , VVy n , and VVθ n  are performed (the first hand-shake quantity calculation (a)). 
   In step S 54 , the hall sensor unit  44   a  detects the position of the movable unit  30   a . The horizontal detected-position signal px and the first and second vertical detected-position signals pyl and pyr are calculated by the hall-sensor signal-processing unit  45 . The horizontal detected-position signal px is then input to the A/D converter A/D  3  of the CPU  21  and converted to the digital signal pdx n , the first vertical detected-position signal pyl is then input to the A/D converter A/D  4  of the CPU  21  and converted to the digital signal pdyl n , and the second vertical detected-position signal pyr is input to the A/D converter A/D  5  of the CPU  21  and also converted to the digital signal pdyr n , both of which thus specify the present position P n  (pdx n , pdyl n , pdyr n ) of the movable unit  30   a  (see ( 2 ) in  FIG. 6 ). 
   In step S 55 , it is determined whether the value of the mirror state parameter MP is set to 1. When it is determined that the value of the mirror state parameter MP is not set to 1, the operation proceeds directly to step S 59 . Otherwise, the operation continues to step S 56 . 
   In step S 56 , the third digital displacement angle Kθ n  is calculated on the basis of the third digital angular velocity VVθ n  (see ( 8 ) in  FIG. 6 ). 
   In step S 57 , the rotational direction component of the position S n , Sθ n  is calculated on the basis of the third digital displacement angle Kθ n  and the hall sensor distance coefficient HSD (see ( 3 ) in  FIG. 6 ). 
   However, the calculations of the first digital displacement angle Kx n , the second digital displacement angle Ky n , the horizontal direction component of the position S n , Sx n , and the vertical direction component of the position S n , Sy n  are not performed. 
   In step S 58 , the position S n  (Sx n , Syl n , Syr n ) where the movable unit  30   a  (the imaging unit  39   a ) should be moved is set to the center of the range of movement of the movable unit  30   a  (Syl n =Syr n ). 
   Therefore, the rotational direction component of the position S n , Sθ n , which is calculated in step S 57 , is not used for calculating in step S 58 . However, the rotational angle (the inclination angle) of the photographing device  1  during the period from when the release switch  13   a  is set to the ON state to when the mirror-up operation is finished, is calculated as the third digital displacement angle Kθ n , and the movement quantity of the movable unit  30   a  to correct the inclination angle is calculated as the rotational direction component of the position S n , Sθ n , and it is used for calculation in steps S 64  and S 65 . 
   Thus, during the period from the time point t 2  of  FIG. 8  to the time point t 3  of  FIG. 8 , the movable unit  30   a  is held at the center of its range of movement, and the calculations of the first, second, and third digital angular velocities VVx n , VVy n , and VVθ n , the third digital displacement angle Kθ n , and the rotational direction component of the position S n , Sθ n  are performed (the second hand-shake quantity calculation (b)). 
   In step S 59 , it is determined whether the value of the anti-shake parameter SR is 0. When it is determined that the value of the anti-shake parameter SR is 0 (SR=0), in other words, that the photographing device  1  is not in the anti-shake mode, the position S n  (Sx n , Syl n , Syr n ) where the movable unit  30   a  should be moved is set to the center of the range of movement of the movable unit  30   a  (Syl n =Syr n ), in step S 60  (see ( 4 ) in  FIG. 6 ). 
   Thus, during the period from the time point t 3  of  FIG. 8  to the time point t 6  of  FIG. 8  and when the photographing device  1  is not in the anti-shake mode, the movable unit  30   a  is held at the center of its range of movement, and the calculations of the first, second, and third digital angular velocities VVx n , VVy n , and VVθ n , are performed (the second hand-shake quantity calculation (a)). 
   When it is determined that the value of the anti-shake parameter SR is not 0 (IS=1), in other words when the photographing device  1  is in anti-shake mode, the first, second, and third digital displacement angles Kx n , Ky n , and Kθ n  are calculated on the basis of the first, second, and third digital angular velocities VVx n , VVy n , and VVθ n , in step S 61  (see ( 7 ) and ( 8 ) in  FIG. 6 ). 
   In step S 62 , it is determined whether the value of the lens resolution parameter RMTF is 0. 
   When it is determined that the value of the lens resolution parameter RMTF is 0, the horizontal direction component of the position S n , Sx n  and the vertical direction component of the position S n , Sy n  are calculated on the basis of the first digital displacement angle Kx n , the second digital displacement angle Ky n , and the lens coefficient F (see ( 3 ) in  FIG. 6 ), in step S 63 . 
   However, the rotational direction component of the position S n , Sθ n , is not calculated and is set to 0. 
   Then, the first vertical direction component of the first driving point Syl n  and the second vertical direction component of the second driving point Syr n  are calculated on the basis of the vertical direction component of the position S n , Sy n  and the rotational direction component of the position S n , Sθ n  (Syl n =Syr n , see ( 4 ) in  FIG. 6 ). 
   When it is determined that the value of the lens resolution parameter RMTF is not 0, the horizontal direction component of the position S n , Sx n  and the vertical direction component of the position S n , Sy n  are calculated on the basis of the first digital displacement angle Kx n , the second digital displacement angle Ky n , and the lens coefficient F (see ( 3 ) in  FIG. 6 ), in step S 64 . 
   Furthermore, the rotational direction component of the position S n , Sθ n , is calculated on the basis of the third digital displacement angle Kθ n  and the hall sensor distance coefficient HSD (see ( 3 ) in  FIG. 6 ). 
   Then, the first vertical direction component of the first driving point Syl n  and the second vertical direction component of the second driving point Syr n  are calculated on the basis of the vertical direction component of the position S n , Sy n  and the rotational direction component of the position S n , Sθ n  (see ( 4 ) in  FIG. 6 ). 
   Thus, during the period from the time point t 3  of  FIG. 8  to the time point t 6  of  FIG. 8 , and when the photographing device  1  is in the anti-shake mode, the movable unit  30   a  is moved to the position S n  where the imaging unit  39   a  should be moved according to the anti-shake operation, and the calculations of the first, second, and third digital angular velocities VVx n , VVy n , and VVθ n , the first, second, and third digital displacement angles Kx n , Ky n , and Kθ n , the horizontal direction component of the position S n , Sx n , the vertical direction component of the position S n , Sy n , the rotational direction component of the position S n , Sθ n , the first vertical direction component of the first driving point Syl n , and the second vertical direction component of the second driving point Syr n  are performed (the third hand-shake quantity calculation (c)). 
   However, when the value of the lens resolution parameter RMTF is 0, the value of the rotational direction component of the position S n , Sθ n , is set to 0 so that the value of the first vertical direction component of the first driving point Syl n  is the same as the value of the second vertical direction component of the second driving point Syr n . 
   In step S 65 , the horizontal driving force Dx n  (the horizontal PWM duty dx), the first vertical driving force Dyl n  (the first vertical PWM duty dyl), and the second vertical driving force Dyr n  (the second vertical PWM duty dyr) of the driving force D n , which moves the movable unit  30   a  to the position S n , are calculated on the basis of the position S n  (Sx n , Sy n , Sθ n ) that was determined in step S 58 , step S 60 , step S 63 , or step S 64 , and the present position P n  (pdx n , pdyl n , pdyr n ) (see ( 5 ) in  FIG. 6 ). 
   In step S 66 , the first and second horizontal coils  31   a   1  and  31   a   2  are driven by applying the horizontal PWM duty dx to the driver circuit  29 ; the first vertical coil  32   a   1  is driven by applying the first vertical PWM duty dyl to the driver circuit  29 ; and the second vertical coil  32   a   2  is driven by applying the second vertical PWM duty dyr to the driver circuit  29 , so that the movable unit  30   a  is moved to position S n  (Sx n , Sy n , Sθ n ) (see ( 6 ) in  FIG. 6 ). 
   The process of steps S 65  and S 66  is an automatic control calculation that is performed by the PID automatic control for performing general (normal) proportional, integral, and differential calculations. 
   In the embodiment, it is explained that the photographing device  1  has the mirror-up operation. However, even if the photographing device  1  does not have the mirror-up operation, if the length of time from when the release button  13  is fully depressed to when the exposure operation commences is long, a benefit in the embodiment will be obtained. In this case, the calculations of the third digital displacement angle Kθ n  and the rotational direction component of the position S n , Sθ n , are performed from a first time point TP 1  after the release switch  13   a  is set to the ON state, for example the time point t 2  immediately after the release switch  13   a  is set to the ON state etc. Furthermore, the calculations of the first and second digital displacement angles Kx n  and Ky n , the horizontal direction component of the position S n , Sx n , and the vertical direction component of the position S n , Sy n , are performed from a second point TP 2  after the first point TP 1 , for example the time point t 3  immediately before the exposure operation commences, etc. 
   Furthermore, it is explained that whether the anti-shake operation for correcting hand-shake caused by roll is performed or not is controlled on the basis of the resolution at the edge of the camera lens  67 . However, not only are the ON/OFF states of the anti-shake operation for correcting hand-shake caused by roll controlled, but the degree of the anti-shake operation for correcting hand-shake caused by roll may also be controlled. 
   For example, when the value of the resolution at the edge is greater than a first threshold value, the anti-shake operation considering the hand-shake caused 100% by roll, in other words, the first vertical direction component of the first driving point Syl n  and the second vertical direction component of the second driving point Syr n  are calculated under the condition that the rotational direction component of the position S n , Sθ n  is considered to be 100% (Syl n =Sy n +100%×Sθ n , Syr n =Sy n −100%×Sθ n ). 
   Furthermore, when the value of the resolution at the edge is greater than a second threshold value that is smaller than the first threshold value, and is not greater than the first threshold value, the anti-shake operation considering the hand-shake caused 50% by roll, in other words, the first vertical direction component of the first driving point Syl n  and the second vertical direction component of the second driving point Syr n  are calculated under the condition that the rotational direction component of the position S n , Sθ n  is considered to be 50% (Syl n =Sy n +50%×Sθ n , Syr n =Sy n −50%×Sθ n ). 
   Furthermore, when the value of the resolution at the edge is not greater than the second threshold value, the anti-shake operation considering the hand-shake caused 0% by roll, in other words, the first vertical direction component of the first driving point Syl n  and the second vertical direction component of the second driving point Syr n  are calculated under the condition that the rotational direction component of the position S n , Sθ n  is considered to be 0% (Syl n =Sy n +0%×Sθ n , Syr n =Sy n −0%×Sθ n ). 
   Furthermore, it is explained that the hall sensor is used for position detection as the magnetic-field change-detecting element. However, another detection element, an MI (Magnetic Impedance) sensor such as a high-frequency carrier-type magnetic-field sensor, a magnetic resonance-type magnetic-field detecting element, or an MR (Magneto-Resistance effect) element may be used for position detection purposes. When one of either the MI sensor, the magnetic resonance-type magnetic-field detecting element, or the MR element is used, the information regarding the position of the movable unit can be obtained by detecting the magnetic-field change, similar to using the hall sensor. 
   Although the embodiment of the present invention has been described herein with reference to the accompanying drawings, obviously many modifications and changes may be made by those skilled in this art without departing from the scope of the invention. 
   The present disclosure relates to subject matter contained in Japanese Patent Application No. 2007-062726 (filed on Mar. 13, 2007), which is expressly incorporated herein by reference, in its entirety.