JP2008191235A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: an unnatural image where an image is deleted is formed because blur can be corrected in a certain direction but blur can not be corrected in other directions according to the position of a blur correction optical system when starting photography. <P>SOLUTION: The camera is equipped with: blur detection means 14X and 14Y detecting the shake amount of a photographing optical system 2; a blur correction means 151 correcting the blur of a subject image; position detection means 154X and 154Y detecting the position of the blur correction means 151; a calculation means 8 calculating a driving amount and a driving direction based on the position of the blur correction means 151 and the shake amount; and driving means 153X and 153Y driving the blur correction means 151 based on the driving amount and the driving direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

Conventionally, as a camera having a camera shake correction function, a camera having a camera shake correction optical system that changes shooting conditions when a shake amount during exposure exceeds a range that can be corrected by the camera shake correction optical system is known. (For example, Patent Document 1).
JP-A-8-110541

  However, in the prior art camera, depending on the position of the blur correction optical system at the start of shooting, the blur can be corrected in one direction, but the blur cannot be corrected in the other direction, resulting in an unnatural image in which an image flows. There is a problem.

The camera according to the invention of claim 1 is a shake detection unit that detects a shake amount of the photographing optical system, a shake correction unit that corrects a shake of a subject image, a position detection unit that detects a position of the shake correction unit, It is characterized by comprising a calculating means for calculating the driving amount and the driving direction based on the position and the shake amount of the blur correcting means, and a driving means for driving the blur correcting means based on the driving amount and the driving direction.
According to a second aspect of the present invention, in the camera according to the first aspect, the shake correcting means is configured to move within a preset driving range, and the calculating means includes a movable distance within the driving range and a position of the shake correcting means. The driving amount is calculated based on the above.
According to a third aspect of the present invention, in the camera according to the first or second aspect, the driving range includes a first area set in the center of the camera and a second area set outside the first area, The means is characterized in that when the position of the shake correction means is in the second region, the drive amount and the drive direction are calculated based on the shake amount and the position of the shake correction means.
According to a fourth aspect of the present invention, in the camera according to any one of the first to third aspects, the calculating means drives the driving amount and driving of the shake correcting means based on the shake amount detected by the shake detecting means before the start of photographing. The direction is calculated.
According to a fifth aspect of the present invention, in the camera according to any one of the first to fourth aspects, when the position of the shake correction means is deviated from the center of the drive range, the calculation means has a drive direction that is the position of the shake correction means. When the moving distance from the driving range to the limit of the driving range is a short direction, the driving amount is calculated based on the position and the shake amount of the blur correction unit, and the driving direction is from the position of the blur correction unit to the limit of the driving range. When the movement distance is in a long direction, the drive amount is calculated based on the shake amount.
According to a sixth aspect of the present invention, in the camera of the fourth aspect, the start of photographing corresponds to the start of the main photographing by fully pressing the release.
According to a seventh aspect of the present invention, in the camera according to any one of the first to sixth aspects, the blur correction unit includes an optical shake prevention device that optically corrects a shake of the subject image, and an imaging that captures the subject image. It is any of the element movement type shake prevention devices that correct the shake of the subject image by moving the element within the light receiving surface.

  According to the present invention, the drive amount of the shake correction unit can be changed according to the position of the shake correction unit.

-First embodiment-
A digital camera provided with a camera shake correction apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1A is a front perspective view of the digital camera according to the first embodiment, and FIG. 1B is a rear perspective view. A photographing lens 2 is attached to the camera body 1. The photographing lens 2 incorporates a camera shake correction device 15 (FIG. 2) described later. On the upper surface of the camera body 1, a release button 3, a power switch 4, and a mode dial 5 for performing a shooting mode setting operation are provided. A liquid crystal monitor 17 is provided on the back of the camera body 1.

FIG. 2 is a block diagram showing the configuration of the digital camera according to the first embodiment. The digital camera includes an image sensor 6, a timing generator 7, a control circuit 8, a driver 9, an AFE circuit 10, an A / D conversion circuit 11, an image processing unit 12, a buffer memory 13, blur detection sensors 14X and 14Y, and a camera shake correction device. 15 and a recording medium 16.
The image sensor 6 is constituted by a CCD or CMOS image sensor provided with a plurality of photoelectric conversion elements corresponding to pixels. The image sensor 6 captures a subject image formed on the imaging surface, and outputs a photoelectric conversion signal corresponding to the brightness of the subject image. The timing generator (TG) 7 generates a timing signal in response to a command sent from the control circuit 8 and supplies the timing signal to each of the driver 9, the AFE (Analog Front End) circuit 10 and the A / D conversion circuit 11. To do.

  The driver 9 generates a drive signal for accumulating charges in the image sensor 6 and sweeping out the accumulated charges using the timing signal. Then, the driver 9 supplies the generated drive signal to the image sensor 6. The AFE circuit 10 performs analog processing (such as gain control) on the signal output from the image sensor 6. The A / D conversion circuit 11 converts the image pickup signal after analog processing into a digital signal.

  The image processing unit 12 is configured, for example, as an ASIC, and performs image processing such as white balance adjustment, saturation correction, and gradation correction on the image signal from the image sensor 6. The control circuit 8 inputs a signal output from each block, performs a predetermined calculation, and outputs a control signal based on the calculation result to each block. In addition, the control circuit 8 performs compression processing on the image data input from the image processing unit 12 by a predetermined method such as JPEG, and records it on the recording medium 16 in a format such as EXIF. Further, the control circuit 8 calculates and controls the shutter speed and the aperture value of the photographing lens 2 based on the luminance of the subject and the imaging sensitivity (ISO sensitivity) calculated based on the image data input from the image processing unit 12. To do. Further, the control circuit 8 controls the drive amount and drive direction of the camera shake correction device 15 based on shake amount signals from the shake detection sensors 14X and 14Y input via the camera shake correction device 15 described later.

  The buffer memory 13 is used to temporarily store data during or after image processing, image compression processing, and display image data creation processing. The display image data is generated by the control circuit 8 based on the image data generated by the image processing unit 12 based on the output from the image sensor 6 or the image data recorded on the recording medium 16. The generated display image data is stored in the buffer memory 13 by the control circuit 8.

  The LCD drive circuit 171 is a circuit that drives the liquid crystal monitor 17 by outputting a drive signal to the liquid crystal monitor 17 based on the control signal of the control circuit 8. The liquid crystal monitor 17 displays an image based on the display image data. The liquid crystal monitor 17 displays various setting menu screens of the digital camera.

  The half-press switch 31 and the full-press switch 32 that are turned on / off in conjunction with the pressing operation of the release button 3 output an on signal or an off signal to the control circuit 8, respectively.

  Next, the operation of the digital camera will be described. When the power of the digital camera is turned on by the user operating the power switch 4 and the mode dial 5 is used to switch to the still image shooting mode, the control circuit 8 sets the still image shooting mode. The control circuit 8 controls the timing generator 7, the image processing unit 12, and the LCD driving circuit 171 to update the image displayed on the liquid crystal monitor 17 with a period of 1/30 seconds, for example. That is, the moving image of the subject is displayed on the liquid crystal monitor 17 as a through image.

  When the user half-presses the release button 3 to instruct preparation for shooting, the control circuit 8 sets the shutter speed, aperture value, and ISO sensitivity based on the photometric value obtained from the image sensor 6. Then, the control circuit 8 sets an aperture value (not shown) to a set aperture value. Further, when the user fully presses the release button 3 to instruct the main photographing, the control circuit 8 controls a shutter (not shown) and also controls the timing generator 7 to set a time corresponding to the set shutter speed. The image pickup device 6 is driven so as to accumulate charges only.

  The image processing unit 12 performs the above-described processing on the image signal output from the image sensor 6 to generate image data. Next, the control circuit 8 executes a compression process on the generated image data. Then, the control circuit 8 generates an image file based on the compressed image data and writes the image file to the recording medium 16.

A description will be given of shake correction at the time of shooting in the digital camera according to the first embodiment.
The shake detection sensors 14X and 14Y are constituted by, for example, an angular velocity sensor, a gyro sensor, or the like, and detect an angular velocity of shake that occurs in the camera body 1 during photographing. The shake detection sensors 14 </ b> X and 14 </ b> Y detect pitching and yawing generated in the camera body 1 when the user sets the shooting mode, and output a shake amount signal to the camera shake correction device 15. The camera shake correction device 15 performs a camera shake correction by driving a shift lens 151 described later based on the input shake amount signal.

  The camera shake correction device 15 includes a shift lens 151, a lens driver 152, actuators 153X and 153Y, and position detection sensors 154X and 154Y. In FIG. 2, the positional relationship among the shift lens 151, the actuators 153 and 153Y, and the position detection sensors 154X and 154Y is shown for convenience. The shift lens 151 is provided so as to be movable in a direction parallel to the imaging surface of the imaging device 6 by the actuators 153X and 153Y. Due to the movement of the shift lens 151, the subject light that has passed through the photographing lens 2 is refracted in a direction that cancels the shake. As a result, the shake of the optical image due to the shake of the camera body 1 is corrected.

  Actuators 153X and 153Y are, for example, voice coil motors having coils, magnets, and yokes. The actuators 153X and 153Y generate a driving force according to the voltage applied by the lens driver 152 to move the shift lens 151. The position detection sensors 154X and 154Y are, for example, magnetic sensors having a magnet and a magnetic detection element, and detect the position of the shift lens 151.

  The shake amount signals output from the shake detection sensors 14X and 14Y and the position signals output from the position detection sensors 154X and 154Y are input to the control circuit 8 via the lens driver 152. The control circuit 8 calculates a drive amount of the shift lens 151 for correcting shake based on the input shake amount signal and position detection signal, and outputs the drive amount signal to the lens driver 152 as a drive amount signal. The lens driver 152 applies a voltage to the actuators 153X and 153Y based on the input drive amount signal.

  FIG. 3 shows a driving range of the shift lens 151 in a plane orthogonal to the optical axis. The shift lens 151 having a diameter L2 is driven within a range in which a preset width of one side is surrounded by a frame A having an L1. FIG. 3 shows a state where the shift lens 151 is located at the center of the driving range. That is, the shift lens 151 can be driven by the distance L1 / 2 in the vertical and horizontal directions from the state shown in FIG. Note that the coordinate axes are set with the horizontal direction in FIG. 3 as the x axis and the vertical direction as the y axis.

  FIG. 4 shows a state in which the shift lens 151 is driven from the state shown in FIG. 3 by a distance a in the + x direction and a distance b in the + y direction. In the state of FIG. 4, the amount that the shift lens 151 can be driven in the + x direction is (L1 / 2−a). Therefore, the amount that the shift lens 151 can be driven in the + x direction is reduced by a, compared to the case where the shift lens 151 is positioned at the center of the drive range. In the −x direction, the driveable amount of the shift lens 151 is (L1 / 2 + a), and thus the amount of the shift lens 151 that can be driven in the −x direction is increased by a.

  Similarly, the amount of shift lens 151 that can be driven in the + y direction is (L1 / 2−b). Therefore, the amount that the shift lens 151 can be driven in the + y direction is reduced by b, compared with the case where the shift lens 151 is positioned at the center of the drive range. In the −y direction, the amount that the shift lens 151 can be driven is (L1 / 2 + b), and thus the amount that the shift lens 151 can be driven in the −y direction is increased by b.

  When the control circuit 8 receives a shooting mode selection operation signal from the mode dial 5 in a state where the shift lens 151 is at the position shown in FIG. Display the image as a through image. At this time, the control circuit 8 calculates the drive amount of the shift lens 151 based on the shake amount signals from the shake detection sensors 14X and 14Y. Then, the control circuit 8 outputs a drive amount signal corresponding to the calculated drive amount to the lens driver 152. The lens driver 152 applies a voltage to the actuators 153X and 153Y based on the input drive amount signal. As a result, the shift lens 151 is driven by the drive amount calculated by the control circuit 8.

  A case will be described in which main shooting is instructed by the user's full-press operation of the release button 3 in a state where the shift lens 151 is driven to the position shown in FIG. When the control circuit 8 inputs an ON signal from the full-press switch 32, the drive amounts M1 and M2 of the shift lens 151 are calculated based on the shake amount signals from the shake detection sensors 14X and 14Y at the time of shooting start. Further, the control circuit 8 determines the drive direction of the shift lens 151 based on the input shake amount signal. The drive amount M1 is a drive amount in the x direction, and the drive amount M2 is a drive amount in the y direction.

  Further, the control circuit 8 inputs a position signal output from the position detection sensors 154X and 154Y at the time of shooting start. The control circuit 8 determines whether the driving direction of the shift lens 151 is a direction in which the moving distance from the position of the shift lens 151 to the limit of the frame A is short based on the input position signal and the above driving direction. . When the driving direction of the shift lens 151 is a direction with a short movement distance, that is, the + x or + y direction in FIG. 4, the control circuit 8 controls the control coefficient K1 (K1 ≦ 1) with respect to the driving amount M1 of the shift lens 151, or A control coefficient K2 (K2 ≦ 1) for the drive amount M2 is calculated. The control coefficient K1 is a coefficient for the drive amount M1 in the + x direction, and the control coefficient K2 is a coefficient for the drive amount M2 in the + y direction.

The control coefficients K1 and K2 are calculated using the following equations (1) and (2).
K1 = ((L1 / 2) -a) / (L1 / 2) (1)
K2 = ((L1 / 2) -b) / (L1 / 2) (2)

  As described above, in FIG. 4, the driveable amount ((L1 / 2) -a) of the shift lens 151 in the + x direction is the case where the shift lens 151 shown in FIG. 3 is located at the center of the drive range. It is reduced by a from the driveable amount L1 / 2. Accordingly, the control circuit 8 multiplies the drive amount M1 by the control coefficient K1 calculated by the above equation (1) to drive the shift lens 151 in the + x direction from the center of the drive range. Make it smaller. Similarly, also in the + y direction, the control circuit 8 reduces the drive amount by multiplying the drive amount M2 by the control coefficient K2 calculated by the above equation (2).

  Based on the calculated drive amounts M1 and M2 and the control coefficients K1 and K2, the control circuit 8 calculates control drive amounts Mc1 = K1 × M1 and Mc2 = K2 × M2 which are smaller than the original drive amounts (M1, M2). Thus, a drive amount signal corresponding to the control drive amounts Mc1 and Mc2 is output to the lens driver 152. The lens driver 152 applies a voltage to the actuators 153X and 153Y based on the input drive amount signal. As a result, the shift lens 151 is driven by the control drive amounts Mc1 and Mc2 calculated by the control circuit 8, and the control drive amounts Mc1 and Mc2 do not exceed the drive range. In the prior art, when the shift lens 151 starts the blur correction at a position shifted from the center of the driving range, the blur cannot be corrected even if the shift lens 151 is driven in the predetermined direction to the limit of the driving range, Only the blur was left and the subject flowed in that direction. However, by calculating and driving the control drive amounts Mc1 and Mc2, the blur cannot be completely corrected, but an unnatural image that flows only in a predetermined direction can be prevented. The control drive amounts Mc1 and Mc2 vary depending on the drive start position of the shift lens 151. As the drive start position of the shift lens 151 is closer to the center, the drive coefficients K1 and K2 become closer to 1, and sufficient blur correction can be performed.

  When the drive direction of the shift lens 151 is a direction in which the distance from the position of the shift lens 151 to the limit of the frame A is long, that is, in the −x or −y direction in FIG. 4, the control circuit 8 calculates the calculated drive. The amounts M1 and M2 are output to the lens driver 152 as drive amount signals. Then, the lens driver 152 applies a voltage to the actuators 153X and 153Y based on the input drive amount signal. As a result, the shift lens 151 is driven by the drive amounts M1 and M2 calculated by the control circuit 8. In this case, since the drive amount of the shift lens 151 in the −x direction and the −y direction is larger than that at the center of the drive range as shown in FIG. 3, the shift lens 151 is driven with the drive amounts M1 and M2. it can. Therefore, since it is not necessary to make the driving amount of the shift lens 151 relatively small, the control circuit 8 does not calculate the control coefficients K1 and K2. FIG. 5 shows the correspondence between the position of the shift lens 151, the driving direction, and the driving amount.

The camera shake correction operation of the digital camera according to the first embodiment will be described with reference to the flowchart shown in FIG. Each processing procedure in FIG. 6 is performed by executing a program in the control circuit 8. A program for performing each process of FIG. 6 is stored in a memory (not shown), and is activated when a shooting mode selection operation signal is input from the mode dial 5.
In step S1, the above-described camera shake correction process at the time of through image shooting is performed, and the process proceeds to step S2. In step S2, it is determined whether or not the release button 3 has been fully pressed. When an ON signal is input from the full push switch 32, an affirmative determination is made in step S2, and the process proceeds to step S3. When the ON signal is not input from the full push switch 32, a negative determination is made in step S2, and the process returns to step S1.

  In step S3, the drive amounts M1 and M2 of the shift lens 151 are calculated based on the shake amount signals from the shake detection sensors 14X and 14Y, and the process proceeds to step S4. In step S4, a position signal indicating the current position of the shift lens 151 output from the position detection sensors 154X and 154Y is input, and the process proceeds to step S5.

  In step S5, it is determined whether or not the control coefficients K1 and K2 need to be calculated. If calculation of the control coefficients K1 and K2 is necessary, that is, if the drive direction of the shift lens 151 is a direction with a short movement distance, an affirmative determination is made in step S5 and the process proceeds to step S6. In step S6, control coefficients K1 and K2 are calculated using the above-described equations (1) and (2), and the process proceeds to step S7.

  If the drive direction of the shift lens 151 is a direction in which the moving distance is long, a negative determination is made in step S5, and step S6 is skipped and the process proceeds to step S7. In step S7, a driving amount signal is output to the lens driver 152, and camera shake correction processing at the time of actual photographing is performed, and the process proceeds to step S8. In step S8, it is determined whether or not the main photographing process is finished. When the main photographing process is completed, an affirmative determination is made in step S8 and the process proceeds to step S9. If the actual shooting is in progress, a negative determination is made in step S8, and the process waits in step S8 until the actual shooting is completed.

  In step S9, it is determined whether or not the power is turned off. If an off signal is input from the power button 4, an affirmative determination is made in step S9, and the series of processing ends. If no off signal is input from the power button 4, a negative determination is made in step S9 and the process returns to step S1.

According to the digital camera including the camera shake correction apparatus according to the first embodiment described above, the following operational effects can be obtained.
(1) The control circuit 8 calculates the drive amount of the shift lens 151 based on the shake amount signals detected by the shake detection sensors 14X and 14Y before the start of photographing. When the start of shooting is instructed, the control circuit 8 calculates the drive amounts M1 and M2 of the shift lens 151 based on the shake amount signals detected by the shake detection sensors 14X and 14Y at the start of shooting. Further, the control circuit 8 calculates the control drive amounts Mc1 and Mc2 according to the position signal of the shift lens 151 by the position detection sensors 153X and 153Y and the drive amounts M1 and M2, and changes the drive amount of the shift lens 151. I tried to do it. Therefore, it is not necessary to return the shift lens 151 to the center of the driving range, and the time until the photographing operation is performed can be shortened. The shooting start corresponds to the start of the main shooting by the control circuit 8 based on the ON signal input from the full-press switch 8.

(2) The control circuit 8 sets the length L1 / 2 of the driving range of the shift lens 151 set in advance and the distances a and b from the center of the driving range of the shift lens 151 detected by the position detection sensors 153X and 153Y. Are used to calculate the driveable amounts (L1 / 2) -a and (L1 / 2) -b of the shift lens 151. Then, the control circuit 8 controls the control coefficient based on the length L1 / 2 of the driving range of the shift lens 151 and the driveable amounts (L1 / 2) -a and (L1 / 2) -b of the shift lens 151. K1 and K2 were calculated. The control circuit 8 calculates the control drive amounts Mc1 and Mc2 using the calculated control coefficients K1 and K2, and changes the drive amount of the shift lens 151. Therefore, by making the drive amount of the shift lens 151 relatively small, the drive amount of the shift lens 151 does not exceed the frame A that is a driveable range. As a result, since the driving amount exceeds the driving range of the shift lens 151, the shake of the subject image is not partially corrected, and an unnatural image in which only a part of the image flows can be prevented. .

(3) The case where the position of the shift lens 151 is deviated from the center of the drive range, and the drive direction of the shift lens 151 is a direction in which the moving distance from the position of the shift lens 151 to the limit of the frame A is short. In addition, the control circuit 8 changes the drive amount of the shift lens 151 to the control drive amounts Mc1 and Mc2. Therefore, it is possible to prevent an unnatural image such as a subject flowing in a predetermined direction.

  Further, when the position of the shift lens 151 is deviated from the center of the drive range, and the drive direction of the shift lens 151 is a direction in which the moving distance from the position of the shift lens 151 to the limit of the frame A is long. The control circuit 8 drives the shift lens 151 based on the blur detection sensors 14X and 14Y. Accordingly, when the shift lens 151 is driven in a direction in which the moving distance is long, the shift lens 151 is driven with the drive amounts M1 and M2, so that the shake of the subject image is reliably corrected.

-Second Embodiment-
A camera shake correction apparatus for a digital camera according to the second embodiment will be described with reference to FIG. The same components as those of the camera according to the first embodiment are given the same reference numerals, and differences from the digital camera according to the first embodiment will be mainly described.
FIG. 7 shows a drive range in a plane orthogonal to the optical axis of the shift lens 151 in the second embodiment. In the second embodiment, a frame B is provided at the center of the frame A as a shift lens control amount switching range. The frame B has a side length of 2α in the x direction and a length of 2β in the y direction. When the shift lens 151 is positioned within the range of the frame B at the start of shooting, the control circuit 8 does not limit the drive amounts M1 and M2 of the shift lens 151. When the shift lens 151 is positioned within the range surrounded by the frame A and the frame B at the start of photographing and is driven in a direction in which the driveable amount decreases, the control circuit 8 sets the drive amount M1 of the shift lens 151, Add a limit to M2. FIG. 7 shows a state in which the shift lens 151 is driven from the state shown in FIG. 3 by a distance a in the + x direction and a distance b in the + y direction.

  It is assumed that the main photographing is instructed by the user fully pressing the release button 3 in a state where the shift lens 151 is in the frame B (for example, a state where the shift lens 151 is driven to the position shown in FIG. When the control circuit 8 inputs an ON signal from the full-press switch 32, the shift lens is based on the shake amount signals input from the shake detection sensors 14X and 14Y at the time of starting the imaging, as in the case of the first embodiment. The driving amounts M1 and M2 of 151 are calculated. Further, the control circuit 8 determines the driving direction of the shift lens 151 based on the input shake amount signal.

  Further, the control circuit 8 inputs position signals output from the position detection sensors 154X and 154Y at the start of photographing. The control circuit 8 determines whether or not the shift lens 151 is positioned within the range of the frame B based on the input position signal. Then, the control circuit 8 determines whether or not the drive direction of the shift lens 151 is a narrow direction based on the input position signal and the drive direction. When the position of the shift lens 151 exceeds the frame B and the driving direction is the direction in which the moving distance of the shift lens 151 is short, that is, the + x or + y direction in FIG. 7, the control circuit 8 drives the shift lens 151. Control coefficients K1 and K2 for M1 and M2 are calculated.

The control coefficients K1 and K2 are calculated using the following equations (3) and (4).
K1 = (((L1 / 2) −a) / (L1 / 2)) × (((L1 / 2) −α) / (L1 / 2)) (3)
K2 = (((L1 / 2) −b) / (L1 / 2)) × (((L1 / 2) −β) / (L1 / 2)) (4)

  As described above, the amount that the shift lens 151 can be driven in the x direction beyond the frame B is ((L1 / 2) −α), and can be driven when the shift lens 151 is located at the center of the drive range. Less than the critical amount (L1 / 2). Further, the amount (L1 / 2) −a that can be driven in the + x direction of the shift lens 151 at the start of blur correction is greater than the amount L1 / 2 that can be driven when the shift lens 151 is located at the center of the drive range. Only has decreased. Therefore, the control circuit 8 multiplies the drive amount M1 by the control coefficient K1 calculated by the above equation (3) to calculate the control drive amount Mc1 = K1 × M1, thereby driving the shift lens 151 in the + x direction. Is made relatively small as compared with the case of driving from the center of the driving range. As a result, even when the shift lens 151 is positioned between the frame B and the frame A at the start of photographing, the shift lens 151 does not exceed the frame A of the drive range with the control drive amount Mc1. Similarly, in the + y direction, the control circuit 8 multiplies the drive amount M2 by the control coefficient K2 calculated by the above equation (4) to calculate the control drive amount Mc2 = K2 × M2, thereby shifting at the start of photographing. Even when the lens 151 is positioned between the frame B and the frame A, the shift lens 151 does not exceed the frame A of the driving range.

  If the shift lens 151 is located in the range of the frame B and the driving direction of the shift lens 151 is the + x direction at the start of photographing, the control circuit 8 does not calculate the control coefficient K1. Similarly, the case where the shift lens 151 is located in the range of the frame B and the driving direction of the shift lens 151 is the + y direction. The control circuit 8 does not calculate the control coefficient K2. Accordingly, when the position and the driving direction of the shift lens 151 satisfy the above-described conditions, the control circuit 8 does not relatively reduce the driving amount, so that an appropriate image blur correction can be performed according to the input shake amount signal.

  In the state shown in FIG. 7, when the drive direction of the shift lens 151 is the -x or -y direction, the control circuit 8 outputs the calculated drive amounts M1 and M2 to the lens driver 152 as drive amount signals. In this case, since the drive amount of the shift lens 151 in the −x direction and the −y direction is larger than that at the center of the drive range as shown in FIG. 3, the shift lens 151 is driven with the drive amounts M1 and M2. However, the frame A of the driving range is not exceeded. Therefore, since it is not necessary to make the driving amount of the shift lens 151 relatively small, the control circuit 8 does not calculate the control coefficients K1 and K2. FIG. 8 shows a correspondence relationship between the position, the driving direction, and the driving amount of the shift lens 151 according to the second embodiment.

According to the digital camera including the camera shake correction apparatus according to the second embodiment described above, the following functions and effects can be obtained in addition to the functions and effects obtained in the first embodiment.
A frame B is provided as a shift lens control amount switching range at the center of the frame A, which is the driving range of the shift lens 151. When the position of the shift lens 151 detected by the position detection sensors 153X and 153Y at the start of photographing is an area surrounded by the frame B, the control circuit 8 does not change the drive amounts M1 and M2 of the shift lens 151. When the position of the shift lens 151 is a region surrounded by the frame B and the frame A at the start of photographing, and the drive direction of the shift lens 151 is a direction with a short moving distance, the control circuit 8 controls the control drive amount Mc1, The shift lens 151 is driven by Mc2. Therefore, when the shift lens 151 is detected in the frame B, the shake is reliably corrected by driving the shift lens 151, and the shift lens 151 is detected in a range surrounded by the frame A and the frame B. In this case, it is possible to prevent an unnatural image in which a part of the image flows.

The embodiment described above can be modified as follows.
(1) Instead of the one that drives the shift lens 151 and corrects the shake amount, a CCD shift method that drives the image sensor 6 in a direction that cancels the shake may be used. In this case, the control circuit 8 outputs a drive amount signal to the actuators 153X and 153Y based on the shake amount signals input from the shake detection sensors 14X and 14Y. The actuators 153X and 153Y may drive the image sensor 6 within the light receiving surface based on the input drive amount signal.

(2) The control coefficients K1 and K2 are experimentally calculated instead of those calculated by the control circuit 8 based on the drive range L1 / 2 and the driveable amount (L1 / 2-a). A value obtained in advance may be used. In this case, correction coefficients K1 and K2 are associated with the position and drive amount of the shift lens 151 and stored in a predetermined storage area of the control circuit 8. Then, the corresponding control coefficients K1 and K2 may be read based on the shake amount signals input from the shake detection sensors 14X and 14Y and the position signals output from the position detection sensors 154X and 154Y.

(3) Although it has been described that the camera shake correction device 15 is provided in a digital camera, it may be provided in an interchangeable lens.

  In addition, the present invention is not limited to the above-described embodiment as long as the characteristics of the present invention are not impaired, and other forms conceivable within the scope of the technical idea of the present invention are also within the scope of the present invention. included.

It is a figure explaining the external appearance of the digital camera in embodiment of this invention. It is a block diagram explaining the circuit structure of the digital camera in embodiment of this invention. It is a figure explaining the drive range of the shift lens in the plane orthogonal to the optical axis of the camera-shake correction apparatus in an embodiment. It is a figure which shows the state which the shift lens drove on the plane orthogonal to an optical axis by the distance a to + x direction and the distance b to + y direction. It is a figure explaining the correspondence of the position of a shift lens, the drive direction, and the drive amount in 1st Embodiment. 3 is a flowchart for explaining the operation of the digital camera in the embodiment. It is a figure which shows the drive range in the plane orthogonal to the optical axis of the shift lens of the camera-shake correction apparatus in 2nd Embodiment. It is a figure explaining the correspondence of the position of a shift lens, the drive direction, and the drive amount in 2nd Embodiment.

Explanation of symbols

2 Shooting Lens 6 Image Sensor 8 Control Circuit 14X, 14Y Shake Detection Sensor 15 Shake Correction Device 151 Shift Lens 153X, 153Y Actuator 154X, 154Y Position Detection Sensor

Claims (7)

Blur detection means for detecting the shake amount of the photographing optical system;
Blur correction means for correcting shake of the subject image;
Position detection means for detecting the position of the blur correction means;
A calculation means for calculating the drive amount and the drive direction based on the position of the shake correction means and the shake amount;
A camera comprising: drive means for driving the shake correction means based on the drive amount and drive direction. The camera of claim 1,
The blur correction unit is configured to move within a preset driving range,
The camera is characterized in that the calculation means calculates the drive amount based on a movable distance within the drive range and a position of the blur correction means. The camera according to claim 1 or 2,
The driving range includes a first area set at the center thereof, and a second area set outside the first area,
The camera is characterized in that the driving amount and driving direction are calculated based on the shake amount and the position of the shake correcting means when the position of the shake correcting means is in the second region. The camera according to any one of claims 1 to 3,
The camera is characterized in that the calculation means calculates a drive amount and a drive direction of the shake correction means based on the shake amount detected by the shake detection means before the start of photographing. The camera according to any one of claims 1 to 4,
When the position of the blur correction unit is deviated from the center of the driving range, the driving means is a direction in which the moving distance from the position of the blur correction unit to the limit of the driving range is short. The drive amount is calculated based on the position of the shake correction unit and the shake amount, and the driving direction is a direction in which the moving distance from the position of the shake correction unit to the limit of the drive range is long, A camera characterized in that the drive amount is calculated based on the shake amount. The camera according to claim 4, wherein
The camera is characterized in that the start of shooting corresponds to the start of main shooting by pressing the release fully. The camera according to any one of claims 1 to 6,
The blur correction unit includes an optical shake prevention device that optically corrects the shake of the subject image, and an element that corrects the shake of the subject image by moving an imaging element that captures the subject image within the light receiving surface. A camera characterized by being one of mobile shake prevention devices.

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