JP2014130259A - Optical equipment, imaging apparatus, and method for controlling optical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the power consumption of an imaging apparatus, while accurately correcting an image blur during a photographing operation.SOLUTION: Optical equipment includes shake detection means which can be switched between a normal mode where the shake of the apparatus is detected and a sleep mode where the shake of the apparatus is not detected and detects the shake of the apparatus, arithmetic means for calculating a correction amount by using the output of the shake detection means, image blur correction means for correcting the image blur on the basis of the correction amount, and control means for controlling the arithmetic means, so as to make the followability of the image blur correction means to the image blur, in the sleep mode lower than that in the normal mode.

Description

  The present invention relates to an image shake correction technique for correcting image shake caused by shake such as camera shake in an imaging apparatus such as a camera.

  Recent cameras have been commercialized with an image shake control device (consisting of an image shake correction unit, drive unit, and shake detection unit, etc.) that prevents image shake due to camera shake, etc. There are almost no factors to do this.

  Here, an image blur control apparatus for preventing image blur will be briefly described. The camera shake of the photographer's camera is usually a vibration of 1 Hz to 10 Hz as a frequency. Then, in order to be able to take a picture without image blur even when such a camera shake occurs at the shutter release time, a camera shake is detected and an image blur correction lens (in accordance with the detected value ( Hereinafter, the correction lens) and the image sensor must be displaced.

  Therefore, in order to take a picture with no image shake even if the camera shakes, it is necessary to first detect the camera shake accurately and secondly correct the optical axis change due to the camera shake. Become.

  In a camera with an image shake correction mechanism, for example, the shake detection unit is used in an image playback mode for displaying captured images or in a power saving mode in which the liquid crystal power is turned off when there is no operation for a certain period of time from the user. It continues to operate and consumes power.

  In order to solve this problem, Patent Document 1 discloses that when the angular velocity sensor is in an operation stop state, the power supply to some modules of the angular velocity sensor such as a vibrator or an amplifier is cut off, and the voltage value of the output signal is set. Power consumption is suppressed by making it the same as the reference voltage.

JP 2006-325075 A

  However, the angular velocity sensor generally has a variation inherent in the angular velocity sensor in the reference voltage, and also varies due to a temperature drift of the reference voltage. If the reference voltage varies, the image blur correction control is adversely affected when the angular velocity signal is integrated and converted into an angle signal. This is because integration errors are accumulated, the command value calculation of the image blur correction mechanism becomes an erroneous calculation at the start of image blur correction, and the deviation from the actual position of the image blur correction mechanism increases.

  In order to prevent this problem, as is well known, a measure is taken to remove the DC component of the angular velocity sensor by applying a high-pass filter (hereinafter, HPF) to the output signal of the angular velocity sensor.

  In Patent Document 1, as a method of putting the angular velocity sensor into an operation stop state, a method of cutting off power supply to a module in the angular velocity sensor is used. This is a method of making the output voltage to the analog primary HPF coincide with the reference voltage by resetting the analog output signal of the angular velocity sensor, and is not described for the case of a digital output signal.

  If the signal of the angular velocity sensor is handled as a digital signal and the image blur correction mechanism is to be controlled, various digital filter processes are required for the output signal of the angular velocity sensor.

  In Patent Document 1, an angular velocity sensor having a crystal with high accuracy as a vibrator is used as the angular velocity sensor. The quartz type angular velocity sensor has a feature that the variation of the reference voltage of the output signal may be compared with the MEMS type. However, if the same control is performed using an inexpensive MEMS type angular velocity sensor instead of the crystal type, there are the following problems. In other words, the MEMS type angular velocity sensor is easily affected by inherent variations in the reference voltage and temperature drift. Therefore, the output of the angular velocity sensor after returning from the sleep mode cannot be achieved simply by shutting off the power supply to the module in the sensor. Become stable. In other words, it takes time to remove the DC component after returning from the sleep mode, and it takes time until the operation of the image shake correcting mechanism can be started after returning from sleep, and it becomes conspicuous as a field angle deviation.

  The present invention has been made in view of the above-described problems, and an object thereof is to reduce power consumption of an imaging apparatus while accurately performing image blur correction during a shooting operation.

  An optical apparatus according to the present invention can switch between a normal mode for detecting a shake of the apparatus and a sleep mode for not detecting a shake of the apparatus, a shake detection means for detecting a shake of the apparatus, and the shake detection means Calculating means for calculating a correction amount using the output of the image, image blur correcting means for correcting image blur based on the correction amount, and the image blur in the sleep mode than in the normal mode. Control means for controlling the arithmetic means so as to lower the follow-up performance of the image blur correction means for the image blur correction means.

  According to the present invention, it is possible to reduce the power consumption of the imaging apparatus while accurately performing the image blur correction during the photographing operation.

1 is a top view of a camera equipped with an image shake correction apparatus according to an embodiment of the present invention. 1 is a side view of a camera equipped with an image shake correction apparatus according to an embodiment of the present invention. 1 is a block diagram illustrating an internal configuration of a camera including an image blur correction device that is an embodiment of an imaging device of the present invention. FIG. It is a figure explaining the image blurring correction | amendment process in the operation | movement stop state of the angular velocity sensor in one Embodiment of this invention. It is a figure explaining stability of the imaging device in one embodiment of the present invention. It is a figure explaining the cutoff frequency according to the focal distance in one Embodiment of this invention. 6 is a flowchart of image blur correction processing according to an embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1A and FIG. 1B are a plan view and a side view showing a camera as an image pickup apparatus provided with a lens device including an image shake correction apparatus which is an embodiment of the optical apparatus of the present invention. The image shake correction apparatus mounted on this camera has image shake based on shake (hereinafter referred to as angle shake) in which the optical axis rotates at a certain angle from the rotation center, as indicated by arrows 103p and 103y with respect to the optical axis 102 of the photographing optical system. Perform the correction. In addition, image shake correction based on shake (hereinafter, parallel shake) in which the optical axis moves in parallel with the optical axis, indicated by arrows 104p and 104y, is performed.

  The camera 101 includes a release button 105, a camera CPU 106, an image sensor 107, angular velocity sensors 108p and 108y, accelerometers 109p and 109y, a lens driving unit 110, and an image blur correction lens 111. Angular velocity sensors 108p and 108y as angular velocity detecting means detect angular shakes in the directions of arrows 108pa and 108ya, respectively. Further, the angular velocity sensors 108p and 108y serving as the acceleration detecting means detect the parallel shakes indicated by the arrows 109pa and 109ya, respectively. The accelerometers 109p and 109y in the directions of the arrows 108pa and 108ya, respectively. The lens driving unit 110 is an actuator that freely drives an image blur correction lens 111 as an image blur correction member in a direction orthogonal to the optical axis (directions of arrows 110p and 110y in FIGS. 1A and 1B). The lens driving unit 110 includes a magnet and a coil. Then, the image blur correction lens 111 is driven by passing a current corresponding to the image blur correction amount in consideration of both the angular blur correction amount and the parallel blur correction amount to the coil. Note that the driving direction of the image blur correction lens 111 is not limited to the direction orthogonal to the optical axis (the directions of arrows 110p and 110y in FIGS. 1A and 1B). For example, tilt movement (the optical axis rotates at an angle from the rotation center). ) Direction.

  FIG. 2 is a block diagram showing an internal configuration of a camera provided with an image blur correction apparatus which is an embodiment of the imaging apparatus of the present invention. The outputs of the angular velocity sensors 108p and 108y and the accelerometers 109p and 109y are input to the camera CPU 106 via the A / D converter 201 (Analog to Digital converter). At this time, the A / D converter 201 converts the analog angular velocity signals from the angular velocity sensors 108p and 108y and the analog acceleration signals from the accelerometers 109p and 109y.

  The HPF 202 has a function capable of changing its characteristics in an arbitrary frequency band, and outputs a signal in a high frequency band by cutting off a low frequency component included in the angular velocity signal from the A / D converter 201 ( High-pass filter operation). The LPF 203 has a function of changing its characteristics in an arbitrary frequency band, integrates the output from the HPF 202 (integration calculation), and converts it into an angle signal. The target position calculation unit 204 converts the output from the LPF 203 into a movement target position of the image blur correction lens 111 based on the subject distance information 205 and / or the focal length information 206.

  A lens position detection sensor 205 in the image blur correction unit 200 is a position detection sensor such as a Hall element, and detects the current position of the image blur correction lens 111. Then, the drive control unit 112 outputs a deviation between the movement target position from the target position calculation unit 204 and the current position detected from the lens position detection sensor 205 to the lens drive unit 110 as a drive signal. Then, the lens driving unit 110 performs image blur correction by drivingly controlling the image blur correction lens 111 as an image blur correction member in a direction orthogonal to the optical axis based on the drive signal. In the embodiment of the present invention, the image blur correction lens 111 is used as the image blur correction member. However, even if the drive control unit 112 drives the image sensor 107 as the image blur correction member in a direction orthogonal to the optical axis. Good.

  The RAM 208 serves as a temporary storage unit that stores the angular velocity signal from the A / D converter 201. In the present embodiment, the RAM 208 stores an angular velocity signal immediately before the angular velocity sensors 108p and 108y shift to the sleep mode.

  When the user operates the operation unit 115 and receives an instruction to shift to an image reproduction mode that cannot be captured or a power saving mode, the sleep mode determination unit 209 determines to enter the sleep mode. Further, when the user receives a setting instruction to return from the image reproduction mode or the power saving mode, it is determined to cancel the sleep mode.

  The sleep mode control unit 210 controls the angular velocity sensors 108p and 108y to enter the sleep mode. Specifically, the sleep mode control unit 210 stops the operations of the angular velocity sensors 108p and 108y and the accelerometers 109p and 109y during the sleep mode period, and changes the cutoff frequencies of the HPF 202 and the LPF 203. Specifically, the sleep mode control unit 210 increases the cutoff frequency band of the HPF 202 and the LPF 203 from the low frequency side in the state where the angular velocity sensors 108p and 108y and the accelerometers 109p and 109y are stopped during the sleep mode period. Change to the regional side. When the cutoff frequency band of the HPF 202 and the LPF 203 is changed to a higher frequency side, the movement target position of the image blur correction lens 111 gradually moves toward the center of the movable range, and the followability of the image blur correction lens 111 with respect to the shake decreases. This is effective control when it is not desired to reflect the user's intentional operation (for example, panning) in the image blur correction.

  The sleep mode control unit 210 outputs to the angular velocity sensors 108p and 108y and the accelerometers 109p and 109y a constant angular velocity signal (an angular velocity immediately before the transition to the sleep mode) stored in the RAM 208 from time t1 to time t2. Instruct to continue. In the sleep mode period, priority is given to stopping the operation of the angular velocity sensors 108p and 108y, but the operation of the accelerometers 109p and 109y may or may not be stopped. In the following description, it is assumed that the sleep mode control unit 210 stops the operation of the angular velocity sensors 108p and 108 during the sleep mode period.

  Next, the operation of the sleep mode of the angular velocity sensors (angular velocity sensors 108p and 108y) and ON / OFF (normal mode) of the sleep mode according to the embodiment of the present invention will be described with reference to FIG. The sleep mode of the sensor refers to a state in which the current consumption is suppressed by stopping the operations of both the driving circuit and the signal processing circuit of the vibrator inside the sensor (such as an angular velocity sensor). When the camera is turned on, the angular velocity sensors 108p and 108y detect and sample the angular velocity at a certain sampling frequency. The angular velocity sensors 108p and 108y output an angular velocity 301 (angular velocity signal) that is a shake amount detected around the reference voltage 302. Here, the condition that the angular velocity sensors 108p and 108y enter the sleep mode is that the user operates the operation unit 115 to shift to the image reproduction mode or the power saving mode as described above. The sleep mode control unit 210 receives the sleep mode notification from the sleep mode determination unit 209 at time t1, and sets the angular velocity sensors 108p and 108y to the operation stop state. The time t1 is the time when the sleep mode determination unit 209 determines that the sleep mode is entered based on the operation of the operation unit 115, and in this embodiment, the time t1 is the time when the image reproduction mode or the power saving mode is entered. The angular velocity sensors 108p and 108y output signals corresponding to the shake amount during the period until the time t1 when the sleep mode is entered. When shifting to the sleep mode at time t1, the RAM 208 stores the angular velocity immediately before shifting to the sleep mode. That is, the RAM 208 stores the offset value of the angular velocity signal immediately before the sleep mode. Then, the sleep mode control unit 210 controls the output of the angular velocity sensors 108p and 108y to be a constant value. Then, the CPU 106 performs an image blur correction calculation using a constant angular velocity signal (an angular velocity immediately before shifting to the sleep mode) stored in the RAM 208 from time t1 to time t2. Note that time t2 is a timing at which the sleep mode determination unit 209 determines that the sleep mode is to be turned off. After receiving the sleep mode OFF notification at time t2, the sleep mode control unit 210 instructs the angular velocity sensors 108p and 108y to output an angular velocity signal corresponding to the shake amount of the imaging apparatus again.

  Next, image blur correction processing in a state where the angular velocity sensor is stopped in the sleep mode according to the embodiment of the present invention will be described with reference to FIG.

  In the present embodiment, even when the angular velocity sensors 108p and 108y are in the sleep mode, the camera CPU 106 uses the constant angular velocity signal (the angular velocity immediately before shifting to the sleep mode) to move the image blur correction lens 111. Continue to calculate the position. If the camera CPU 106 stops the calculation of the movement target position of the image blur correction lens 111, the image blur correction state continuity is maintained when the sleep is canceled while the force around the angular velocity sensors 108p and 108y immediately before the sleep is maintained. Lost. When the continuity of the image blur correction state is lost, it is necessary to initialize the output of the angular velocity sensors 108p and 108y and start the image blur correction in the same way as when the camera power is turned on.

  In addition to the image blur correction, the camera functions include a function that uses output signals from the shake detection units (angular velocity sensors 108p and 108y and accelerometers 109p and 109y). For this reason, when the output from the shake detection unit is used for functions other than the image shake correction function, there is a concern that the process becomes complicated when the camera CPU 106 attempts to initialize the output from the shake detection unit.

  On the other hand, if the calculation of the movement target position of the image blur correction lens 111 is continued based on the constant angular velocity signal (angular velocity immediately before the transition to the sleep mode) stored in the RAM 208 even during the sleep period, the output of the angular velocity sensor is It becomes a constant value (state without shaking). Therefore, the outputs of the shake detection units (angular velocity sensors 108p and 108y and accelerometers 109p and 109y) are initialized to a state where there is no shaking.

  The image blur correction unit 200 corrects the image blur caused by the camera shake of the photographer by displacing the image blur correction lens 111 within a movable range from the movable lower end 403a to the movable upper end 403c. If the image blur correction lens 111 is controlled near the movable end, there is a possibility that vignetting or a light amount drop may occur or the image blur correction mechanism may oscillate. Therefore, it is desirable that the drive control unit 112 in the image blur correction unit 200 controls the image blur correction lens 111 in the vicinity of the movable range center 403b.

  The broken line in FIG. 4 represents the movement target position of the image blur correction lens 111 after the filter calculation process is performed on the output signal of the shake detection unit. The solid line in FIG. 4 represents the position of the image blur correction lens 111.

  When the angular velocity sensors 108p and 108y shift to the sleep mode at time t1, the image blur correction lens 111 is in a state in which the movable range center 403b is energized and held (a state in which image blur correction is not performed). As described above, the angular velocity sensors 108p and 108y output the value immediately before entering the sleep mode as a constant value. Then, using the output values of the angular velocity sensors 108p and 108y immediately before entering the sleep mode stored in the RAM 208, a filtering process is performed to calculate the movement target position of the image blur correction lens 111. At this time, it is necessary to perform calculation so that the movement target position of the image blur correction lens 111 is near the center of the movable range of the image blur correction lens 111. This is because if the movement target position of the image blur correction lens 111 is far from the center of the movable range of the image blur correction lens 111, the deviation between the current position of the image blur correction lens 111 and the movement target position is large when the sleep mode is canceled. Become. As a result, the angle of view shift when the image blur correction lens 111 moves by this deviation becomes conspicuous.

  Therefore, the target position calculation unit 204 makes the image angle deviation inconspicuous by gradually bringing the image blur correction lens 111 closer to the movement target position over a certain period of time after the sleep mode is released. The image blur correction mechanism does not perform image blur correction during a period in which the image blur correction lens 111 is gradually brought closer to the movement target position over a certain period of time after the sleep mode is released. If the value of the angular velocity immediately before sleep is large and the movement target position of the image blur correction lens 111 is close to the end of the movable range, the camera CPU 106 moves the image blur correction lens 111 near the end of the movable range after canceling the sleep mode. Control. For this reason, the image blur correction mechanism cannot sufficiently perform its function. In addition, the camera can not maximize the optical performance.

  Therefore, in the present embodiment, when the angular velocity sensors 108p and 108y are stopped (sleep mode period), the sleep mode control unit 210 changes the cutoff frequency of the HPF 202 and the LPF 203 from the low frequency side to the high frequency side. . The reason why the cut-off frequencies of the HPF 202 and the LPF 203 are changed to a high frequency is to detect a shake caused by a button operation when the sleep mode is canceled and prevent the angular velocity signals 108p and 108y from being output sharply. Alternatively, when the offset value of the angular velocity signal held just before the sleep is significantly different from the original offset value, a sudden field angle deviation due to a deviation between the current position of the image blur correction lens 111 and the movement target position is prevented. In order to suppress the field angle deviation as much as possible, it is necessary to minimize the deviation between the current position of the image blur correction lens 111 after the sleep release and the movement target position (specifically, the movable range center 403b). When the movement target position of the image blur correction lens 111 is calculated while the cutoff frequency of the HPF 202 and the LPF 203 is low, the calculation result of the movement target position of the image blur correction lens 111 is image blur correction as indicated by a broken line 401 in the figure. It takes time to converge on the movable center of the lens 111. If the angular velocity immediately before the sleep mode is a large value and the period from the sleep mode ON notification to the sleep mode OFF notification is short, the deviation between the current position of the image blur correction lens 111 and the movement target position becomes large. When the cutoff frequency of the HPF 202 and the LPF 203 is set to a high frequency, the time for the movement target position of the image blur correction lens 111 to converge to the movable center of the image blur correction lens 111 is short as indicated by a broken line 402 in the drawing.

  In a state where the angular velocity sensors 108p and 108y are stopped (sleep mode period), the sleep mode control unit 210 changes the cutoff frequency of the HPF 202 and the LPF 203 from the low frequency side to the high frequency side. Then, the locus of the movement target position of the image blur correction lens 111 is as shown in 402 shown in the figure. In other words, the movement target position of the shake correction lens 111 becomes a value near the movable center position of the image shake correction lens 111 as compared with a state where the cutoff frequencies of the HPF 202 and the LPF 203 are on the low frequency side. Then, the deviation between the movement target position after the release of the sleep mode at time t2 and the image blur correction lens 111 becomes small. Therefore, it is possible to suppress the angle of view displacement.

  Note that if the image blur correction lens 111 is made to follow the movement target position in a step shape after the sleep mode is canceled at time t2, there may be a case where the angle of view is misaligned even if the deviation is small. For this reason, the camera CPU 106 performs a process of gradually bringing the image blur correction lens 111 closer to the movement target position over a certain period until time t3. As described above, during the period from time t2 to time t3, the camera CPU 106 does not perform image blur correction by driving the image blur correction lens 111. In particular, on the telephoto side, the amount of image blur relative to the amount of camera shake is larger than that on the wide angle side. For this reason, on the telephoto side rather than the wide-angle side, it is desired to shorten the time from the sleep release to the start of image blur correction (operation start) as much as possible. Therefore, in the present embodiment, the sleep mode control unit 210 changes the cutoff frequencies of the HPF 202 and the LPF 203 according to the focal length.

  Next, how the sleep mode control unit 210 changes the cutoff frequencies of the HPF 202 and the LPF 203 will be described with reference to FIG. The straight line 501 shown is the cutoff frequency of the HPF 202 and LPF 203 with respect to the focal length. First, on the telephoto side, the amount of image blur relative to the amount of camera shake is larger than that on the wide-angle side. The scene that is expected to be exposed the earliest after the sleep mode is released may be in the lens barrel extended state, transitioning to the image playback mode (sleep mode state), and the user pressing the release button or pressing it halfway. Conceivable. At this time, it is desired to start image blur correction as soon as possible on the telephoto side where the image blur amount is larger than the camera shake amount as compared with the wide angle side. Therefore, in this embodiment, if the focal length is equal to or less than the set threshold f1, the sleep mode control unit 210 sets the cutoff frequency Fc1. On the other hand, if the focal length is greater than f1, the sleep mode control unit 210 sets the cutoff frequency Fc2. In the figure, one threshold is set, but two or more thresholds may be set.

  Next, the operation of the image blur correction process of the present embodiment will be described using the flowchart of FIG. After starting the camera, the camera CPU 106 initializes the HPF 201 and the LPF 202 in step S601. By this initialization, initial parameters of the imaging optical system are set. After initialization, the camera is driven in a shooting mode capable of shooting.

  In step S602, the sleep mode determination unit 209 determines whether there is an operation from the user to the image reproduction mode. When shifting to the image reproduction mode, in the present embodiment, the angular velocity sensor enters the sleep mode and enters the operation stop state. In step S604, the camera CPU 106 performs image blur correction processing in the sleep mode. If the image reproduction mode is not shifted in step S602, the process proceeds to step S603, and the sleep mode determination unit 209 determines whether the power saving mode is shifted.

  When the process shifts to the power saving mode in step S603, the process shifts to step S604, and the camera CPU 106 performs an image blur correction process in the sleep mode. If the camera does not shift to the power saving mode in step S603, the camera is in the shooting mode, and the process returns to step S602 again.

  In step S604, the image reproduction mode or the power saving mode is entered. At the beginning of the image blur correction process in the sleep mode, the sleep mode control unit 210 fixes the image blur correction lens 111 at the center position of the movable range and does not perform the image blur correction.

  In step S605, the sleep mode control unit 210 turns on the sleep mode command and puts the angular velocity sensor into the sleep mode state.

  In step S606, the sleep mode control unit 210 changes the cutoff frequency of the HPF 202 and the LPF 203 from a low frequency to a high frequency. At this time, the sleep mode control unit 210 determines whether the focal length when entering the sleep mode is equal to or less than a preset threshold value. If the focal length is less than or equal to a preset threshold, the process proceeds to step S607, and if the focal distance is greater than the preset threshold, the process proceeds to step S608. Here, the reason for changing the cutoff frequency of the HPF 202 and the LPF 203 in accordance with the focal length is that the image blur amount with respect to the camera shake amount is larger on the telephoto side than on the wide angle side. For this reason, the constant values output by the angular velocity sensors 108p and 108y during the sleep mode period tend to increase. During the sleep mode period, the sleep mode control unit 210 fixes the image blur correction lens 111 at the center position of the movable range. Therefore, when the calculation result of the movement target position is converged near the center of the movable range, the image blur amount with respect to the shake amount tends to increase. This is because, on the telephoto side, by changing the cutoff frequencies of the HPF 202 and the LPF 203 to a high frequency, the time to convergence is made faster than on the wide angle side. In the present embodiment, the focal length threshold is set to one, but two or more thresholds may be set.

  In step S607, the sleep mode control unit 210 sets a cutoff frequency on the wide angle side. In step S608, the sleep mode control unit 210 sets a cutoff frequency on the telephoto side. In step S609, the sleep mode control unit 210 counts down at the interrupt cycle from the set value of the cutoff frequency set in step S607 or step S608. In step S610, the sleep mode control unit 210 counts down the cutoff frequency in step S609, and proceeds to step S611 when it reaches zero.

  In step S611, the cutoff frequencies of the HPF 202 and the LPF 203 are shifted to the high frequency side with respect to the movement target position calculation at all focal lengths. Specifically, the camera shake correction calculation is performed in a relatively high frequency region that is equal to or greater than the camera shake region (-10 Hz). In step S611, the image blur correction effect can be lowered, the driving amount of the image blur correction lens 111 is reduced, and the image blur correction lens 111 is moved near the center of the movable range. In the photographing mode, the cutoff frequency of the HPF 202 and the LPF 203 is shifted to the high frequency side on the telephoto side rather than on the wide angle side. Since the image blur amount relative to the camera shake amount is larger on the telephoto side than on the wide angle side, the image blur correction lens 111 is easily displaced from the movable center position to the movable end. Therefore, the image blur correction lens 111 can be returned to the vicinity of the movable center as quickly as possible by changing the cutoff frequency of the HPF 202 and the LPF 203 to a high frequency range. Therefore, in order to converge the movement target position near the movable center of the image blur correction lens 111, the cutoff frequencies of the HPF 202 and the LPF 203 are shifted to the high frequency side over the entire focal length. By doing so, it is possible to prevent a sudden angle-of-view shift after sleep release.

  In step S612, when the user performs a setting for returning from the image reproduction mode or the power saving mode, the sleep mode determination unit 209 determines release of the sleep mode. The sleep mode determination unit 209 instructs the sleep mode control unit 210 to cancel the sleep mode. The sleep mode control unit 210 sets the angular velocity sensors 108p and 108y to sleep OFF and puts the angular velocity sensors 108p and 108y into an operating state.

  In step S613, as in step S606, if the focal length in the sleep mode is equal to or smaller than a preset threshold value, the process proceeds to step S614. If the focal length in the sleep mode is larger than a preset threshold value, the process proceeds to step S615. Note that the threshold value of the focal length set in step S613 may be the same value as in step S606 or may be a different value.

  In step S614, since the focal length during sleep in step S613 is equal to or less than the threshold value, the target position calculation unit gradually brings the image blur correction lens 111 closer to the movement target position over time T1 [ms]. In step S615, since the focal length during sleep in step S613 is larger than the threshold value, the sleep mode control unit 210 gradually brings the image blur correction lens 111 closer to the movement target position over time T2 [ms]. Here, the reason for dividing the time from when sleep is released until the image stabilization lens 111 gradually approaches the movement target position according to the focal length is that the image blur amount relative to the camera shake amount is larger than the wide angle side on the telephoto side. This is because it becomes larger. For this reason, it is desired to start image blur correction as soon as possible on the wide angle side.

  In step S616, since the image blur correction lens 111 follows the movement target position in T1 [ms] in step S614 or T2 [ms] in step S615, the camera CPU 106 starts image blur correction.

  The present invention is not limited to image blur correction apparatuses for digital single-lens reflex cameras and digital compact cameras, and can also be installed in imaging apparatuses such as photographing with digital video cameras and surveillance cameras, web cameras, and mobile phones.

Claims (9)

A shake detection means for detecting a shake of the device, capable of switching between a normal mode for detecting a shake of the device and a sleep mode in which the shake of the device is not detected;
Arithmetic means for calculating a correction amount using the output of the shake detection means;
Image blur correction means for correcting image blur based on the correction amount;
Control means for controlling the computing means so as to lower the follow-up performance of the image blur correction means for the image blur in the sleep mode than in the normal mode;
An optical apparatus comprising: The computing means includes a filter whose cutoff frequency band can be changed,
When the control means is switched from the normal mode to the sleep mode, the follow-up ability of the image shake correction means to the image shake is lowered in the sleep mode than in the normal mode. The optical apparatus according to claim 1, wherein a cutoff frequency band of the filter is changed.   3. The optical device according to claim 2, wherein when the control unit is switched from the normal mode to the sleep mode, the control unit changes a cutoff frequency of the filter unit in accordance with a focal length of a photographing optical system. machine.   The control unit is configured to change a time until the start of operation of the image blur correcting unit according to a focal length of the photographing optical system when the mode is switched from the normal mode to the sleep mode. Item 4. The optical instrument according to Item 2 or 3.   5. The optical apparatus according to claim 2, wherein the cutoff frequency band of the filter is higher in the sleep mode than in the normal mode. It is an optical device used for an imaging device having a photographing mode capable of photographing, a reproduction mode incapable of photographing and a power saving mode
6. The control unit according to claim 1, wherein the control unit switches the shake detection unit from the shooting mode to the sleep mode when the shooting mode is switched to the reproduction mode or the power saving mode. The optical apparatus described in 1.   The said shake detection means is further provided with the memory | storage means which memorize | stores the output of the said shake detection means immediately before switching to the said sleep mode, when switched from the said imaging | photography mode to the said sleep mode. Item 7. The optical apparatus according to any one of Items 1 to 6.   An imaging apparatus comprising the optical device according to claim 1. A shake detection step for detecting a shake of the device, which can be switched between a normal mode for detecting a shake of the device and a sleep mode in which the shake of the device is not detected,
A calculation step of calculating a correction amount using an output from the shake detection step;
An image blur correction step for correcting image blur based on the correction amount;
A control step for controlling the calculation in the calculation step so as to lower the followability of the image blur correction means for the image blur in the sleep mode than in the normal mode;
A method for controlling an optical apparatus, comprising:

Images