JP2005266480A - Blur correction apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a blur correction apparatus capable of preventing an unnatural action by detecting the intentional shake of a photographer, such as composition change or panning, and of performing an effective blur correcting operation even when performing long-second exposure. <P>SOLUTION: The blur correction apparatus is provided with a blur correction control section 120 for judging based on at least a vibration detecting signal whether a shaking state of the apparatus is a non-intentional shake state having much components of the non-intentional shake of a user or an intentional shake state having much components of the intentional shake of the user and for suppressing blur correction in the intentional direction when a result of the judgment is the intentional shake state, thereby the blur correction apparatus corrects the blur of an image to be photographed, wherein the blur correction control section 120 is configured to perform blur correction control of the non-intentional shake state regardless of the vibration detecting signal when a period of exposure seconds of photographing set by a shutter speed setting means 130 is longer than one second. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a shake correction apparatus that is used in a camera, an interchangeable lens, and the like and corrects a shake of a photographed image.

The main vibration source of vibration applied to an optical device such as binoculars and a photographing device such as a camera is user shake. A blur correction device is known as a means for correcting the vibration and blur of an image caused by the hand shake.
The operation of the conventional shake correction apparatus will be described below with reference to FIG.
FIG. 9 is a block diagram showing a basic configuration of a conventional shake correction apparatus including a shake detection apparatus.
The angular velocity sensor 10 is a sensor that detects a shake applied to the shake correction device, and normally uses a piezoelectric vibration type angular velocity sensor that detects a Coriolis force. The output of the angular velocity sensor 10 is transmitted to the reference value calculation unit 40. The reference value calculation unit 40 is a part that calculates a reference value of shake from the output of the angular velocity sensor 10. The shake signal output from the angular velocity sensor 10 is transmitted to the integrating unit 54 after subtracting the reference value. The integration unit 54 is a part that time-integrates a shake signal expressed in units of angular velocity and converts the shake signal into a shake angle of the shake correction apparatus.

  The target drive position calculation unit 56 is a part that calculates target drive position information of the shake correction lens 70 by adding information such as the focal length of the lens to the information on the shake angle obtained by the integration unit 54. The drive signal calculation unit 58 calculates the difference between the target drive position information and the current position information of the shake correction lens 70 in order to drive the shake correction lens 70 according to the target drive position information, and drives the coil 63. Apply current.

  The drive unit 58 is a part for driving the shake correction lens 70, and includes a yoke 61, a magnet 62, and a coil 63. The coil 63 is placed in a magnetic circuit formed by the yoke 61 and the magnet 62. When a current is passed through the coil 63, a force is generated in the coil 63 according to Fleming's left-hand rule. The coil 63 is attached to a lens barrel 72 that houses a shake correction lens 70. Since the blur correction lens 70 and the lens barrel 72 are structured to be movable in a direction perpendicular to the optical axis I, the movement of the coil 63 drives the blur correction lens 70 in a direction perpendicular to the optical axis I. Is possible.

  The optical position detection unit 59 is a part that monitors the movement of the blur correction lens 70, and includes an infrared light emitting diode (hereinafter referred to as IRED) 64, a slit plate 65 having a slit 66, and a PSD (Position Sensitive Device) 67. .

  The light emitted from the IRED 64 first passes through the slit 66, so that the width of the light beam is reduced and reaches the PSD 67. The PSD 67 outputs a signal corresponding to the position of light on the light receiving surface. Since the slit plate 65 is attached to the lens barrel 72, the movement of the blur correction lens 70 becomes the movement of the slit 66, and the movement of the light on the light receiving surface of the PSD 67. Therefore, the position of the light on the light receiving surface of the PSD 67 is equivalent to the position of the blur correction lens 70. The signal output from the PSD 67 is fed back as a position signal 68.

  The vibrations that the user applies to the optical device and the photographing device can be broadly divided into hand shakes not intended by the user and shakes intended by the user such as panning. The blur correction device is an effective means for correcting image vibration and blur due to camera shake not intended by the user. However, if it is left as it is, it will try to correct the vibration caused by the latter panning or the like. In this case, there is a problem that the user's intention and the movement of the image do not match, which makes it very difficult to use.

  In order to solve such a problem, a method of detecting an intended shake (panning, etc.) (Patent Documents 1 and 2), a processing method when an intended shake is detected (Patent Documents 3, 4, and 5), etc. Are intended to improve usability in the intended shake state by stopping the shake correction operation when the intended shake is detected. Alternatively, a method of switching the user's intention with a mode switch (Patent Document 6) is also disclosed, which is a method of reflecting and reflecting a photographer's intention with a mode switch.

However, the above-described conventional method has the following problems in photographing when the exposure time is long (low shutter speed).
In shooting at a low shutter speed with a relatively long finder image loss state, an unstable standing state occurs due to the user's visual blockage, particularly when the finder image is viewed with one eye. Therefore, the amount of blur increases, and large blur due to this often causes vibrations as if intended for panning, etc., so this is erroneously detected as an intended shake, or the blur correction operation is stopped, or However, there is a problem that the effect of blur correction is impaired by the suppression.
JP 05-142614 A Japanese Patent Laid-Open No. 06-197262 Japanese Patent Laid-Open No. 06-347855 JP-A-10-213832 JP 2002-99013 A JP 2003-215562 A

  An object of the present invention is to detect a shake intended by a photographer, such as composition change or panning, so as not to perform an unnatural operation, and to achieve an effective blur even when performing exposure for a long time. It is to propose a shake correction apparatus capable of performing a correction operation.

The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to the Example of this invention is attached | subjected and demonstrated, it is not limited to this.
According to the first aspect of the present invention, the vibration detection unit (10) that detects vibration and outputs a vibration detection signal and the vibration state of the apparatus including the vibration detection unit are not intended to have a large amount of vibration components that are not intended by the user. It is determined based on at least the vibration detection signal whether it is a shake state or an intended shake state with a lot of shake components intended by the user. A blur correction control unit (120) that performs blur correction control that suppresses blur correction in a direction, and corrects blur of a captured image, wherein the blur correction control unit When the exposure time is longer than a predetermined time (1 second), the shake correction device performs shake correction control in an unintended shake state regardless of the vibration detection signal. .

  In the invention according to claim 2, the vibration detection unit (10) that detects vibration and outputs a vibration detection signal and the vibration state of the apparatus including the vibration detection unit are not intended to have a large amount of vibration components that are not intended by the user. It is determined based on at least the vibration detection signal whether it is a shake state or an intended shake state with a lot of shake components intended by the user. A shake correction control unit (120) that performs a shake correction control that suppresses a shake correction in a direction, and a shake correction device that corrects a shake of an image to be shot, wherein the shake correction control unit (120) When the exposure time at the time of shooting is longer than the predetermined time (1 second), a threshold value (threshold value 2) is set so that it is easier to determine that the unintended shake state is present than in other cases. Used when judging the condition. A blur correction device to.

  According to a third aspect of the present invention, in the blur correction device according to the first or second aspect, the predetermined time is 1 second.

  In the invention of claim 4, the vibration detection unit (10) that detects vibration and outputs a vibration detection signal and the vibration state of the apparatus including the vibration detection unit are not intended to have a large amount of vibration components that are not intended by the user. Based on the exposure time at the time of shooting and the vibration detection signal, it is determined whether it is a shake state or an intended shake state with many shake components intended by the user. A blur correction control unit (120) that performs blur correction control that suppresses blur correction in an intended direction, and is a blur correction device that corrects blur of a captured image, The control unit is a shake correction apparatus characterized in that determination is made such that blur correction control in an unintended shake state becomes easier as the exposure time at the time of shooting becomes longer.

  According to a fifth aspect of the present invention, in the shake correction apparatus according to any one of the first to fourth aspects, the shake correction control unit (120) is configured to perform the shake determination when the determination result is an intended shake state. The shake correction apparatus is characterized in that no shake correction is performed for an intended shake component in the vibration detection signal.

According to the present invention, the following effects can be obtained.
(1) When the exposure time at the time of shooting is longer than the predetermined time, the shake correction control unit performs the shake correction control in an unintended shake state regardless of the vibration detection signal. The blur correction can be accurately performed without erroneously determining that the shake due to the standing unstable state that occurs when performing the exposure at the time is an intentional shake.

(2) When the exposure time at the time of shooting is longer than the predetermined time, the blur correction control unit sets a threshold value that makes it easier to determine that the unintended shake state is present than in other cases. Since it is used when determining the shake state, when the long-second exposure is performed, the shake due to the standing unstable state that occurs when performing exposure for a long second is not erroneously determined as the intentional shake, and the panning is performed for a long time. Therefore, it is possible to accurately perform shooting according to the photographer's intention.

(3) Since the predetermined time is 1 second, it is possible to accurately determine an unintended shake due to an unstable standing state and an intended shake in general photographing.

(4) The blur correction control unit makes a determination that makes it easier to perform the blur correction control in an unintended shake state as the exposure time at the time of shooting becomes longer, and thus makes a more natural and detailed shake determination. be able to.

(5) When the determination result is an intended shake state, the shake correction control unit does not perform shake correction for the intended shake component in the vibration detection signal, so that shooting such as panning and composition change is performed. A natural operation can be performed without correcting blurring for the shake intended by the person.

  The purpose of enabling an effective shake correction operation even when exposure is performed for a long time is realized by changing the content of the shake correction control for a long time.

FIG. 1 is a block diagram illustrating an outline of a shake correction apparatus in an embodiment of the present invention.
The blur correction apparatus in the present embodiment is an apparatus used in a single-lens reflex camera system including a camera body 90 and an interchangeable lens 80 that is detachable from the camera body 90.
The camera body 90 is a so-called digital still camera body that has an imaging element (not shown) and captures an image formed on the imaging surface of the imaging element by the imaging optical system of the interchangeable lens 80. May be a camera body. Further, instead of a single-lens reflex camera system with interchangeable lenses, a non-lens-replaceable lens such as a so-called compact camera may be used.

  The half-press switch SW1 is a switch that is turned on in conjunction with a half-press operation of a release button (not shown). When the half-press switch SW1 is turned on, a series of photographing preparation operations such as photometry calculation by a photometry unit (not shown) and autofocus drive by an autofocus drive unit (not shown) are started. If the half-press timer 100 is OFF, the half-press timer 100 is turned ON in synchronization with the half-press switch SW1 being turned ON.

  The full push switch SW2 is a switch that is turned on in conjunction with a full push operation of further pushing a release button (not shown). When this switch is turned on, a series of photographing operations such as opening / closing of a shutter by a shutter mechanism (not shown) and imaging by an image sensor (not shown) are performed.

  The half-press timer 100 is a timer that is turned on at the same time that the half-press switch SW1 is turned on. The half-press timer 100 remains ON while the half-press switch SW1 is ON, and remains ON for a certain time even after the half-press switch SW1 is OFF. The half-press timer 100 starts counting as soon as it is turned on, and continues counting while it is on.

  The power supply unit 110 is a part that supplies power to each part of the camera. When the half-press timer 100 of the camera is ON, the power supply unit 110 supplies power to the places where power is required in the camera system, including the angular velocity sensor 10. Keep doing. When the half-press timer 100 is OFF, the power supply unit 110 stops supplying power to the angular velocity sensor 10 and the like. Therefore, the camera vibration can be detected by the angular velocity sensor 10 only while the camera half-press timer 100 is ON.

The angular velocity sensor 10 is a vibration detection unit that detects vibration applied to the camera by an angular velocity value, detects the angular velocity using the Coriolis force applied to the angular velocity sensor 10, and outputs the detection result as a voltage signal. It is.
The voltage signal output from the angular velocity sensor 10 is transmitted to the amplification unit 20. Further, the angular velocity sensor 10 can detect the angular velocity only while power is supplied from the power supply unit 110.
Normally, since it is necessary to detect angular velocities in the two-axis directions, two similar angular velocity sensors 10 are mounted. However, for simplicity, one axis is not illustrated.

  The amplifying unit 20 is an amplifying unit that amplifies the output voltage value of the angular velocity sensor 10. An angular velocity signal (hereinafter, shake detection signal) amplified by the amplification unit 20 is transmitted to the shake state determination unit 30, the reference value calculation unit 40, and the drive signal calculation unit 50.

The shake correction control unit 120 is a one-chip microcomputer having a shake state determination unit 30, a reference value calculation unit 40, a drive signal calculation unit 50, and the like.
The shake state determination unit 30 is a determination unit that determines a shake state using the shake detection signal transmitted from the amplification unit 20 and the shutter speed obtained from the shutter speed setting unit 130. In the shake state determination unit 30, the shake of the camera is a shake intended by the photographer (a shake state due to an intentional action performed by the photographer, such as composition change, panning, or moving object tracking), or an unintentional shake (shooting) It is determined whether the person intends to be stationary but is experiencing vibration due to camera shake or the like.

The shake state determination unit 30 basically has a magnitude of an absolute value of a difference value between a shake detection signal obtained within a predetermined time and a reference value calculated by a reference value calculation unit 40 (to be described later) When the vibration amount is larger than a predetermined value (threshold value 1), it is determined that the vibration is intended, and otherwise, it is determined that the vibration is not intended. However, if the shutter speed (exposure time) is set to a longer time than a predetermined time by a shutter speed setting means 130 described later, it is determined that the shake is not intended (see FIG. 3 described later). The reason for this is that when the shutter speed (exposure time) is longer than the predetermined time, the photographer's visual interruption due to the raising operation of the mirror (not shown) becomes longer during the exposure, and the standing is unstable. A state occurs, and hence the amount of blur increases, and a large blur due to this may be determined to be an intended shake, so this is erroneously detected as moving object tracking and the blur correction operation is stopped, or This is to prevent suppression.
The determination result of the shake state determination unit 30 is transmitted to the reference value calculation unit 40.

  The reference value calculation unit 40 calculates a reference value for calculating the drive signal from the shake detection signal transmitted from the amplification unit 20. The reference value calculation unit 40 changes the calculation method based on the determination result transmitted from the shake state determination unit 30. An example of an arithmetic expression is shown below.

Here, ω is a shake detection signal, and ω ₀ is a shake reference value. The suffix t attached to these variables is a variable representing elapsed time, and in this embodiment, it is represented by the number of times of sampling, and is an integer value. Each of these equations represents a moving average of shake detection signals, but the number of data used for averaging differs between an unintended shake state and an intended shake state.

  The reference value for the unintended shake state is desirably a value close to the zero output value of the angular velocity sensor. The frequency of the zero output signal of the angular velocity sensor 10 is much lower than the frequency of human hand shaking. Therefore, the reference value may be extracted from the low frequency component of the shake detection signal. Therefore, the reference value of the shake detection signal is calculated by calculating the shake detection signal, that is, the moving average of the shake. In order to extract only the lowest frequency components as much as possible, the number K0 of data used for the moving average is increased.

In an intended shake, the shake detection signal varies more greatly than an unintended shake. For example, in panning or the like, since the photographer intentionally shakes the camera, the amount of shake is larger than the unintended shake and the frequency is also lowered.
It is not preferable to make corrections until then when the shake intended by the photographer is included as in panning. Therefore, in the intended shake state, the number K1 of data used for the moving average is made smaller than the number K0 of data in the unintended shake state. This speeds up the response of the reference value to the low-frequency shake detection signal, so that the composition can be determined as intended by the photographer, and shake correction is performed for the shake intended by the photographer. Therefore, it is possible to perform blur correction only for unintended shakes.
The reference value calculated by the reference value calculation unit 40 is transmitted to the drive signal calculation unit 50.

The drive signal calculation unit 50 calculates a drive signal for driving the shake correction lens 70 using the shake detection signal transmitted from the amplification unit 20 and the reference value transmitted from the reference value calculation unit 40. It is a calculating part. The drive signal calculation unit 50 subtracts the reference value from the shake detection signal and performs an integral calculation to convert the angular velocity signal into an angular displacement signal and further convert it into a drive signal for the shake correction lens 70. The drive signal calculated by the drive signal calculation unit 50 is transmitted to the drive unit 60.
The present embodiment shows an example in which the shake state determination unit 30, the reference value calculation unit 40, and the drive signal calculation unit 50 are all incorporated and integrated in a shake correction control unit 120 formed by a one-chip microcomputer. These may be formed by separate chips or the like.

  The drive unit 60 is a drive unit that drives the shake correction lens 70 based on the drive signal from the drive signal calculation unit 50. The drive unit 60 includes an actuator for driving the shake correction lens 70, a position detection sensor for detecting the position of the shake correction lens 70, and the like.

  The blur correction lens 70 is a part of an imaging optical system (imaging optical system) (not shown), and includes a single lens or a plurality of lenses that can move in a plane substantially orthogonal to the optical axis. This is a blur correction optical system including a lens group. The blur correction lens 70 is driven by the drive unit 60 in a direction substantially orthogonal to the optical axis I to deflect the optical axis I of the imaging optical system.

Image blur such as a photograph occurs when an image on an imaging plane (in this embodiment, an imaging plane of an image sensor) moves during exposure due to vibration applied to the camera such as camera shake. However, the shake correction camera as shown in FIG. 1 has a built-in vibration detection sensor such as the angular velocity sensor 10, and the vibration applied to the camera can be detected by the vibration detection sensor. If the vibration applied to the camera is detected, the movement of the image on the imaging plane due to the vibration can be known. Therefore, the blur correction lens 70 is moved so that the movement of the image on the imaging plane stops. Thus, the movement of the image on the image plane, that is, the blur can be corrected.
The shutter speed setting means 130 is a means for setting the shutter speed by AE (automatic exposure) or manual setting. The shutter speed set by the shutter speed setting unit 130 is transmitted to the shake state determination unit 30.

Next, the operation of the camera in the first embodiment will be described.
FIG. 2 is a flowchart illustrating the operation flow of the camera according to the first embodiment.
The flow in FIG. 2 starts when the main power of the camera is turned on and ends when the main power is turned off.
In step (hereinafter simply referred to as S) 10, it is determined whether or not the half-press switch SW1 is ON. If the half-press switch SW1 is ON, the process proceeds to S20, and if it is OFF, the process proceeds to S90.
In S20, it is determined whether or not the half-press timer 100 is OFF. If the half-press timer 100 is OFF, the process proceeds to S30, and if it is ON, the process proceeds to S100.
In S30, the half-press timer 100 is turned on. Proceeding to this step means that the half-press switch is turned ON only when the half-press timer 100 is OFF, and the half-press timer 100 is also turned ON in synchronization with the half-press switch being turned ON.

In S40, the angular velocity sensor 10 is turned on and angular velocity detection is started. In S30, the half-press timer 100 is turned on, power supply to the angular velocity sensor 10 is started, and vibration detection by the angular velocity sensor 10 becomes possible.
In S50, the calculation of the reference value is started.
In S <b> 60, calculation of a drive signal for the shake correction lens 70 and drive of the shake correction lens 70 are started.
In S70, it is determined whether or not the full push switch SW2 is ON. If the full push switch SW2 is ON, the process proceeds to S80, and if it is OFF, the process returns to SIO.
In S80, a photographing operation is performed. A series of photographing operations such as opening / closing of a shutter by a shutter mechanism (not shown) and imaging by an image sensor (not shown) are performed. After the photographing operation is completed, the process returns to S10.

In S90, it is determined whether or not the half-press timer 100 is ON. If the half-press timer 100 is ON, the process proceeds to S100, and if not, the process proceeds to S130.
In S100, the angular velocity sensor 10 is kept on. While the half-press timer 100 is ON, power is supplied to the angular velocity sensor 10, so that the angular velocity sensor 10 can detect vibration.
In S110, the calculation of the reference value is continued. The reference value calculation expression is typically the above-mentioned moving average, but other low-frequency transmission type digital filters may be used.
The details of this step will be described later in detail.
In S120, the calculation of the drive signal for the shake correction lens 70 and the drive of the shake correction lens 70 are continued. An example of drive signal calculation is shown below.

In S130, if the blur correction lens 70 has been driven at the time of proceeding to this step, the drive of the blur correction lens 70 is stopped. In addition, when the driving of the vibration reduction lens 70 is stopped at the time of proceeding to this step, this step is skipped.
In S140, if the calculation of the reference value has been performed at the time of proceeding to this step, the calculation of the reference value is stopped. If the calculation of the reference value has already been stopped at the time of proceeding to this step, this step is skipped.
In S150, when power is supplied to the angular velocity sensor 10 at the time of proceeding to this step, the supply of power to the angular velocity sensor 10 is stopped, the angular velocity sensor 10 is turned off, and then the process returns to S10. If the angular velocity sensor 10 has already been turned off, this step is skipped.

FIG. 3 is a block diagram illustrating a control flow of the shake state determination unit 30 and the reference value calculation unit 40 according to the first embodiment. FIG. 3 shows the operation in S110 of FIG. 2 in detail.
In S111, it is determined whether or not the shake amount is larger than the threshold value 1. When the shake amount is larger than the threshold value 1, the process proceeds to S112, and when the shake amount is not larger than the threshold value 1, the process proceeds to S116.
In S112, it is temporarily determined that the shake is the intended shake. Note that this step is added to facilitate understanding of the present invention, and may be omitted as an actual operation.

In S113, the shutter speed setting means 130 determines whether or not the shutter speed (exposure time) is set longer than 1 second. If the exposure time is set longer than 1 second, the process proceeds to S116, and if the exposure time is not set longer than 1 second, the process proceeds to S114.
Here, with the exposure time of 1 second as a boundary, the long time side and the other cases are divided. The standing up unstable state starts to occur in the photographer who has the single-lens reflex camera system in this embodiment. However, it is based on the experimental result that it is from the place exceeding about 1 second. In addition, the single-lens reflex camera system in a present Example has the form similar to a general single-lens reflex camera system, and the same weight. Therefore, in other general single-lens reflex camera systems, it can be said that a good result can be obtained if the value of 1 second is set to a predetermined time.

In S114, it is determined that the intended shake is present.
In S115, a reference value calculation for an intended shake is performed. Specifically, the calculation of the reference value is performed by the equation (2) shown above. After completing this step, the flow returns to the flow of FIG.
In S116, it is determined that the shake is not intended.
In S117, unintended shake reference value calculation is performed. Specifically, the calculation of the reference value is performed by the equation (1) shown above. After completing this step, the flow returns to the flow of FIG.

FIG. 4 is a graph illustrating the conditions for the shake state determination unit 30 to determine shake in the first embodiment.
In this embodiment, when the shake amount is larger than the threshold value 1, it is basically determined that the shake is intended. However, when the shutter speed is set to a predetermined value (1 second) or more by the shutter speed setting means 130, an unstable standing state due to the photographer's visual blockage occurs, and the amount of blur increases accordingly. There is a possibility that it is erroneously determined that the shake is intended to cause a large shake due to the above, and the shake correction operation is stopped or suppressed. Therefore, in such a case, even if the calculation result of the shake state determination is an intended shake so that there is no inconvenience (stopping or suppressing blur correction) due to this judgment error, the shake is unintended. Is determined.

  According to the present embodiment, an unsteady standing state that occurs when performing exposure for a long time while detecting a shake intended by the photographer such as composition change or panning to prevent unnatural operation. Therefore, it is possible to accurately perform the blur correction without determining that the shake due to the error is an intentional shake.

Since the second embodiment is an example in which the shake state determination operation in the first embodiment is changed, the same functions as those in the first embodiment are denoted by the same reference numerals, and repeated description is omitted as appropriate. .
FIG. 5 is a block diagram illustrating a flow of control of the shake state determination unit 30 and the reference value calculation unit 40 according to the second embodiment. FIG. 5 shows in detail the operation in S110 of FIG. 2 in the first embodiment.
In S211, it is determined whether or not the shake amount is larger than the threshold value 1. When the shake amount is larger than the threshold value 1, the process proceeds to S212, and when the shake amount is not larger than the threshold value 1, the process proceeds to S217.
In S212, it is temporarily determined that the intended shake is present. Note that this step is added to facilitate understanding of the present invention, and may be omitted as an actual operation.

  In S213, the shutter speed setting unit 130 determines whether the shutter speed (exposure time) is set to a time longer than 1 second. If the exposure time is set to be longer than 1 second, the process proceeds to S217. If the exposure time is not set to be longer than 1 second, the process proceeds to S214.

In S214, it is determined whether or not the shake amount is larger than the threshold value 2. Here, the threshold 2 is a value corresponding to a shake larger than the threshold 1, and there is a relationship of threshold 2> threshold 1. When the shake amount is larger than the threshold value 2, the process proceeds to S215, and when the shake amount is not larger than the threshold value 2, the process proceeds to S217.
In S215, it is determined that the shake is the intended shake.
In S216, a reference value calculation for an intended shake is performed. Specifically, the calculation of the reference value is performed by the equation (2) shown above. After completing this step, the flow returns to the flow of FIG.
In S217, it is determined that the shake is not intended.
In S218, a reference value calculation for unintended shake is performed. Specifically, the calculation of the reference value is performed by the equation (1) shown above. After completing this step, the flow returns to the flow of FIG.

FIG. 6 is a graph illustrating the conditions for the shake state determination unit 30 to determine shake in the second embodiment.
In the first embodiment, when the exposure time is 1 second or longer, it is determined that the shake is unintended. However, in the second embodiment, when the exposure time is 1 second or longer, the intended shake is determined. The threshold value for determining whether or not the threshold value is larger than the threshold value 1 is set to a threshold value 2.
As described in the first embodiment, when an unstable standing state occurs due to a photographer's visual interruption in shooting at a long time, even if the photographer tries to stop, the body shakes and a large shake occurs. However, if there is a shake that is larger than the large shake due to the standing unstable state, it is possible that the photographer is intentionally taking a panning shot rather than the possibility that the shake is caused by the standing unstable state. High nature. Therefore, in this embodiment, when the exposure time is 1 second or longer, the threshold value for determining the intended shake is set to the threshold value 2 having a shake amount larger than the threshold value 1, and the panning is performed for a long time. It is possible to make an appropriate judgment.

  According to the present embodiment, the case of performing a panning shot in a long time without erroneously determining that the shake due to the standing unstable state that occurs when performing the exposure for a long time is an intentional shake. It is possible to carry out photographing in accordance with the photographer's intention by accurately determining.

Since the third embodiment is an example in which the shake state determination operation in the first embodiment is changed, the same functions as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted as appropriate. .
In the first and second embodiments, the change in the threshold value for determining the shake state is different from the exposure time of 1 second. However, in this embodiment, this change is smoothed to perform a more natural operation. It is made to be able to.
FIG. 7 is a block diagram illustrating a flow of control of the shake state determination unit 30 and the reference value calculation unit 40 according to the third embodiment. FIG. 7 shows in detail the operation in S110 of FIG. 2 in the first embodiment.
FIG. 8 is a graph illustrating conditions for the shake state determination unit 30 to determine shake in the third embodiment. The vertical axis in FIG. 8 is the shake amount Y, and the horizontal axis is the exposure time X. In this embodiment, the threshold boundary line for determining the shake state is a straight line of Y = a · X + b. In addition, this boundary line does not need to be a straight line on FIG. 8, and may be a broken line or a curved line.

Hereinafter, the operation will be described by taking as an example a case where the shutter speed is t seconds and the shake amount is y ₁ .
In S311, it is determined whether y ₁ is larger than (a · t + b). If y ₁ is greater than (a · t + b), the process proceeds to S312. If y ₁ is not greater than (a · t + b), the process proceeds to S314.
In the example shown in FIG. 8, P (t, y ₁ ) is on the upper side of the line Y = a · X + b, ie, y ₁ is larger than (a · t + b). It will be.
In S312, it is determined that the intended shake has occurred.

In S313, a reference value calculation for an intended shake is performed. Specifically, the calculation of the reference value is performed by the equation (2) shown above. After completing this step, the flow returns to the flow of FIG.
In S314, it is determined that the shake is not intended.
In S315, a reference value calculation for unintended shake is performed. Specifically, the calculation of the reference value is performed by the equation (1) shown above. After completing this step, the flow returns to the flow of FIG.
According to this embodiment, as the exposure time at the time of shooting becomes longer, the threshold value is continuously changed so that blur correction control in an unintended shake state is easily performed. Can be determined.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
(1) In each embodiment, the example in which the determination of the shake state determination unit 30 is changed according to the shutter time is shown. However, the present invention is not limited to this. For example, the shake correction operation itself can be performed without changing the determination result of the shake state. May be changed directly.

(2) In each embodiment, an example in which the shake correction control suitable for each state is performed by changing the arithmetic expression of the reference value between the intended shake state and the unintended shake state is shown. For example, it is possible not to perform only the shake correction operation in the direction in which the intended shake occurs, or to use other methods to make the shake suitable for the intended shake state and the unintended shake state. Correction control may be performed.

(3) In the first and second embodiments, the example in which the determination content of the shake state is changed with the shutter time being 1 second as the predetermined time is not limited to this. For example, the focal length of the photographing optical system is changed. The predetermined time may be changed as appropriate.

It is a block diagram explaining the outline | summary of the blurring correction apparatus in the Example of this invention. 3 is a flowchart illustrating the operation flow of the camera according to the first exemplary embodiment. FIG. 6 is a block diagram illustrating a control flow of a shake state determination unit 30 and a reference value calculation unit 40 according to the first embodiment. FIG. 6 is a graph illustrating conditions for determining a shake by the shake state determination unit 30 in the first embodiment. FIG. 10 is a block diagram illustrating a flow of control of a shake state determination unit 30 and a reference value calculation unit 40 in the second embodiment. FIG. 6 is a graph illustrating conditions for determining a shake by the shake state determination unit 30 in the second embodiment. FIG. 10 is a block diagram illustrating a flow of control of a shake state determination unit 30 and a reference value calculation unit 40 according to a third embodiment. FIG. 10 is a graph illustrating conditions for determining a shake by the shake state determination unit 30 in the third embodiment. It is a block diagram which shows the basic composition of the conventional blurring correction apparatus containing a shake detection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Angular velocity sensor 20 Amplification part 30 Shaking state determination part 40 Reference value calculation part 50 Drive signal calculation part 60 Drive part 70 Shake correction lens 80 Interchangeable lens 90 Camera body 100 Half-press timer 110 Power supply part 120 Shake correction control part 130 Shutter speed Setting means SW1 half push switch SW2 full push switch

Claims (5)

A vibration detector that detects vibration and outputs a vibration detection signal;
Whether the shake state of the apparatus including the vibration detection unit is an unintended shake state in which there are many unintended shake components of the user or an intentional shake state in which there are many shake components intended by the user. A blur correction control unit that performs a blur correction control for determining blur correction in an intended direction when the determination result is determined based on the vibration detection signal and the determination result is an intended shake state;
A blur correction device that corrects blurring of a captured image,
The blur correction control unit performs blur correction control of an unintended shake state regardless of the vibration detection signal when the exposure time at the time of shooting is longer than a predetermined second time,
A blur correction device characterized by the above. A vibration detector that detects vibration and outputs a vibration detection signal;
Whether the shake state of the apparatus including the vibration detection unit is an unintended shake state in which there are many unintended shake components of the user or an intentional shake state in which there are many shake components intended by the user. A blur correction control unit that performs a blur correction control for determining blur correction in an intended direction when the determination result is determined based on the vibration detection signal and the determination result is an intended shake state;
A blur correction device that corrects blurring of a captured image,
When the exposure time at the time of shooting is longer than a predetermined time, the shake correction control unit sets a threshold value that makes it easier to determine that the unintended shake state is present than in other cases. To use when judging
A blur correction device characterized by the above. The blur correction device according to claim 1 or 2,
The predetermined time is 1 second;
A blur correction device characterized by the above. A vibration detector that detects vibration and outputs a vibration detection signal;
Photographing whether the shake state of the apparatus including the vibration detection unit is an unintended shake state with a lot of shake components unintended by the user or an intention shake state with many shake components intended by the user A blur correction control unit that performs a blur correction control that suppresses blur correction in an intended direction in a case where the determination result is an intended shake state, based on the exposure time at the time and the vibration detection signal;
A blur correction device that corrects blurring of a captured image,
The blur correction control unit performs a determination that makes it easier to perform blur correction control of an unintended shake state as the exposure time at the time of shooting becomes a longer time,
A blur correction device characterized by the above. In the blur correction device according to any one of claims 1 to 4,
The shake correction control unit does not perform shake correction for an intended shake component of the vibration detection signal when the determination result is an intended shake state;
A blur correction device characterized by the above.

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