JPH09218435A - Image blurring correction camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect the translational vibration of a camera, to efficiently obtain initial velocity, to accurately correct image blurring and to obtain a distinct image by providing an acceleration detection part, a speed arithmetic calculation part, a displacement arithmetic calculation part, a correction driving quantity arithmetic calculation part and a correction driving part which are respectively specified. SOLUTION: Displacement is calculated by removing a gravitational acceleration component from the output values of acceleration detection devices 1 to 3 and using only an acceleration component produced by translational motion. In this camera, the speed arithmetic calculation part calculates the speed by using the acceleration from the first peak to the last peak at specified time intervals out of the detected acceleration. The displacement arithmetic calculation part calculates the displacement in the midst of correcting the image blurring from the speed calculated by the speed arithmetic calculation part. The correction driving quantity arithmetic calculation part 11 calculates the image blurring quantity based on the displacement calculated by the displacement arithmetic calculation part and calculates the driving quantity of a lens for correction so that the image blurring quantity may be negated. The correction driving part 12 drives the lens for correction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image blur correction camera for correcting image blur caused by camera shake or the like that occurs during shooting.

[0002]

2. Description of the Related Art Conventionally, an image blur correction camera having an image blur correction device has been known in order to correct an image blur that occurs during photographing. The image blur correction device is provided in a part of the photographing lens system for canceling the blur based on the output of the blur sensor while the shutter is open when the blur sensor provided in the camera detects the blur. The lens is driven to correct image blur.

26 and 27 are block diagrams showing first and second examples of conventional image blur correction cameras, respectively.
These are disclosed in JP-A-3-37616 and JP-A-3-46642. Further, FIG. 28 is a schematic configuration diagram of a correction optical device of a conventional image blur correction camera (JP-A-5-158100). The one in FIG. 26 is
Angular velocity detection devices 23 and 24, and correction drive amount calculation means 25
And a correction driving device 26. Angular velocity detector 2
3 and 24 are the X axis and Y of the camera orthogonal to the optical axis of the camera.
Detects the angular velocity (blurring) around the axis. The correction drive amount calculation means 25 is based on the displacement (rotation angle) in the X-axis and Y-axis directions calculated from the outputs of the angular velocity detection devices 23 and 24.
The drive amount of the correction lens 38 is calculated to cancel the blur. The correction drive device 26 drives the correction lens 38 according to the calculated drive amount, and corrects the image blur generated in the camera.

FIG. 27 shows an acceleration detecting device 27, 2
8, an angular velocity detecting device 29, 30, an object distance measuring device 31, a correction drive amount calculating device 32, and a correction drive device 33. The acceleration detection devices 27 and 28 detect the acceleration of the camera in the X-axis and Y-axis directions. The angular velocity detection devices 29 and 30 detect the angular velocity around the X axis and the Y axis of the camera. The subject distance measuring means 31 measures the distance between the subject and the camera. The correction drive amount calculation means 32 has a displacement (movement amount) in the Y-axis direction calculated by the output of the acceleration detection device 28 and a displacement (rotation angle) about the X-axis calculated by the output of the angular velocity detection device 29. Based on the output from the subject distance measuring means 31, in order to cancel the blur,
The amount of rotation about the X axis is calculated. Similarly, based on the displacement in the X-axis direction calculated by the output of the acceleration detection device 27, the displacement around the Y-axis calculated by the output of the angular velocity detection device 30, and the output of the subject distance measuring means 31, The rotation amount around the Y axis is calculated in order to cancel the blur. The correction drive device 33 rotates the optical system of the image pickup device around the X-axis and the Y-axis in accordance with these calculated drive amounts, and corrects image blur in the Y-axis and X-axis directions, respectively.

[0005]

However, the above-mentioned conventional image blur correction camera has the following problems. In the case of FIG. 26, the camera shake is detected only by the angular velocity detecting devices 23 and 24, so that the shake in the translational direction of the camera cannot be detected. Therefore, there is a problem in that it is not possible to correct the image blur caused by the blur in the translation direction. In particular, when the photographing magnification is high, there is a problem that the image quality is remarkably deteriorated because the image blur caused by the blur in the translational direction of the camera is large.

27, the acceleration detecting device 2 is shown.
7, 28, the translational vibration of the camera can be detected. However, when the camera is accompanied by rotational vibration, the rotational acceleration of the camera changes the gravitational acceleration component acting on the acceleration detection devices 27 and 28. Therefore, the acceleration acting on the acceleration detection devices 27 and 28 is an acceleration including a gravitational acceleration component, and is different from the acceleration generated only by the translational vibration of the camera. Furthermore, in order to integrate the acceleration to calculate the velocity, the value of the initial velocity is required to determine the integration constant. However, if the acceleration including the gravity acceleration component is used when calculating the initial velocity, the initial velocity is The calculation accuracy of is reduced. Due to these factors, the translational vibration could not be detected accurately. Therefore, there is a problem that the image blur cannot be accurately corrected and a clear image cannot be obtained.

In order to solve this problem, the applicant of the present invention corrects the image blur by calculating the velocity and the displacement from the acceleration from which the gravitational acceleration component has been removed, so that even if the gravitational acceleration component changes An image blur correction camera capable of correcting image blur has already been proposed (Japanese Patent Application No. 7-232387). In these cases, it is necessary to integrate the acceleration in order to obtain the velocity and the displacement from the acceleration, but when the integration is performed, an integration constant, that is, an initial condition is necessary. In particular, the initial velocity at the start of integration is required to obtain the velocity from the acceleration when performing image blur correction of the camera. In order to calculate the translational displacement after the start of the camera exposure (t1), the acceleration is integrated from time t0 to t1 which is a predetermined time before t1, and the integrated value, that is, the initial value at t0 so that the speed vibrates around 0. The speed V0 is calculated.
Using this result, the initial velocity at t1 can be obtained. In this method, the calculation accuracy of the speed changes depending on the value of the predetermined time (t1-t0), and the predetermined time (t1-t0) may be 10 seconds or more in order to improve the accuracy.

Conventionally, a method has been used in which integration is started with a stationary state as an initial state and the velocity is set to 0 for calculation. When this method is used for image blur correction of a camera, it is necessary to start integration with the camera stationary, and there is a problem that it is inconvenient or difficult to realize the stationary state. Furthermore, if the time from the stationary state to shooting is long, the accumulation of integration errors that occur during integration during that time causes
The displacement error required at the time of shooting becomes large. In addition, since it is necessary to constantly detect acceleration and continue integral calculation for a long time from a stationary state to shooting, a large amount of power is required to operate the acceleration detector and calculation means, especially for a camera using a battery. Is a problem. Furthermore, if the integral calculation is interrupted even once between the stationary state and the photographing, there is a problem that it is necessary to set the stationary state again.

It is an object of the present invention to accurately detect the translational vibration of the camera and efficiently obtain the initial velocity, thereby accurately correcting the image blur and obtaining a clear image.

[0010]

According to a first aspect of the present invention, there is provided an acceleration detecting section (1, 2 ,,) for detecting an acceleration acting on a camera.
3) and the acceleration detected by the acceleration detecting unit between the first peak value time and the last peak value time in a predetermined time interval, the first peak value time and the last peak value are used. A velocity calculation unit that calculates a velocity from the acceleration by assuming that the displacement of the camera at the time of value is equal, and a displacement calculation unit that calculates the displacement during image blur correction from the velocity calculated by the velocity calculation unit. A correction drive amount calculation unit (11) for calculating an image blur amount based on the displacement calculated by the displacement calculation unit and calculating a drive amount of the correction lens and / or the imaging surface to cancel the image blur amount. And a correction drive unit (12) for driving the correction lens and / or the imaging surface.

According to a second aspect of the present invention, an acceleration detecting section (1, 2, 3) for detecting accelerations acting on the camera in the three axial directions.
And an angular velocity detection unit (4, 5, 6) for detecting an angular velocity around the three axes acting on the camera, an initial posture of the camera with respect to the stationary coordinate system and the angular velocity around the three axes, and the camera coordinate system and the stationary coordinate system. A posture calculation unit (9) for calculating a coordinate conversion matrix between the above and the following, a gravity acceleration component calculation unit (10) for calculating a gravity acceleration component in the camera coordinate system using the coordinate conversion matrix, and the gravity acceleration component. Using the acceleration from the first peak value to the last peak value in the predetermined time interval among the accelerations from which the camera has been removed, the camera displacements at the first peak value and the last peak value are equal. And a displacement calculator that calculates the displacement during image blur correction from the velocity calculated by the velocity calculator. A subject distance measuring unit (7) for measuring the distance between the camera and the subject, a photographing magnification detecting unit (8) for detecting the photographing magnification of the camera, and the displacement in the X-axis and Y-axis directions or the triaxial direction. , An image blur amount based on a rotation angle about the X-axis and the Y-axis or about the three-axis calculated from an angular velocity about the X-axis and the Y-axis or about the three-axis, a distance between the camera and a subject, and the photographing magnification. And a correction drive amount calculation unit (11) that calculates the drive amount of the correction lens and / or the imaging surface to cancel the image blur amount, and the correction drive that drives the correction lens and / or the imaging surface. Division (12)
And characterized in that:

According to a third aspect of the present invention, there is provided an acceleration detecting section (1, 1, which detects accelerations acting on the camera in the X-axis and Y-axis directions.
2), an angular velocity detection unit (4, 5, 6) that detects the angular velocity around the three axes acting on the camera, and a posture detection unit (13) that detects the posture of the camera by detecting the gravitational acceleration direction. A posture calculation unit (9) that calculates a coordinate conversion matrix between a camera coordinate system and a stationary coordinate system from the camera posture and the angular velocities around the three axes, and the camera coordinate system using the coordinate transformation matrix. Acceleration component calculating unit (10) for calculating the gravity acceleration component in
Of the acceleration from which the gravitational acceleration component is removed, the acceleration between the first peak value time and the last peak value time in a predetermined time interval is used to determine the first peak value time and the last peak value time. And a displacement calculation unit that calculates a velocity from the acceleration by assuming that the displacements of the cameras are equal, a displacement calculation unit that calculates a displacement during image blur correction from the velocity calculated by the velocity calculation unit, and a camera. Subject distance measurement unit (7) that measures the distance to the subject
And a photographing magnification detection unit (8) for detecting the photographing magnification of the camera
Based on the displacement in the X-axis and Y-axis directions, the rotation angle about the X-axis and the Y-axis calculated from the angular velocities about the X-axis and the Y-axis, the distance between the camera and the subject, and the photographing magnification. A correction drive amount calculation unit (11) for calculating the image blur amount and calculating the drive amount of the correction lens and / or the imaging surface to cancel the image blur amount; and the correction lens and / or the imaging surface. And a correction driving unit (12) for driving.

According to a fourth aspect of the present invention, an acceleration detecting section (1, 2, 3) for detecting accelerations acting on the camera in the three axial directions.
And an angular velocity detection unit (4, 5, 6) for detecting an angular velocity around the three axes acting on the camera, an initial posture of the camera with respect to the stationary coordinate system and the angular velocity around the three axes, and the camera coordinate system and the stationary coordinate system. A posture calculation unit (9) for calculating a coordinate conversion matrix between the above and the following, a gravity acceleration component calculation unit (10) for calculating a gravity acceleration component in the camera coordinate system using the coordinate conversion matrix, and the gravity acceleration component. Using the acceleration from the first peak value to the last peak value in the predetermined time interval among the accelerations from which the camera has been removed, the camera displacements at the first peak value and the last peak value are equal. And a displacement calculator that calculates the displacement during image blur correction from the velocity calculated by the velocity calculator. From the subject distance measuring unit (7) for measuring the distance between the camera and the subject, the photographing magnification detecting unit (8) for detecting the photographing magnification of the camera, the displacement in the three axis directions, and the angular velocity around the three axes. An image blur amount and a focus shift amount are calculated based on the calculated rotation angles around the three axes, the distance between the camera and the subject, and the shooting magnification, and correction is performed to cancel the image blur amount and the focus shift amount. Drive amount calculation unit (1) for calculating the drive amount of at least one of the lens for focusing, the imaging surface, and the focusing lens.
1) and a correction driving unit (12) for driving at least one of the correction lens, the imaging surface, and the focusing lens.

The invention of claim 5 is the invention of claim 2 or claim 4.
In the image blur correction camera described in (3), the posture calculation unit calculates an initial posture of the camera with respect to a stationary coordinate system from a gravitational acceleration direction in the camera coordinate system obtained from acceleration in the three axis directions.

According to a sixth aspect of the present invention, in the image blur correction camera according to any one of the first to fifth aspects, the acceleration detection unit is a full-push switch after the half-push switch of the camera is turned on. It is characterized in that the speed is calculated from the acceleration until is turned on.

According to a seventh aspect of the present invention, in the image blur correction camera according to any one of the first to sixth aspects, in the speed calculating section, the acceleration detecting section detects acceleration of one cycle or more. In this case, the speed is calculated, and when the acceleration detecting unit does not detect the acceleration of one cycle or more, the photographing process is performed without performing the image blur correction, or the photographing process is stopped.

According to an eighth aspect of the present invention, in the image blur correction camera according to any one of the first to seventh aspects, in the speed calculating section, the acceleration detecting section is configured to accelerate at or above the predetermined time interval. When the acceleration is detected, the speed is calculated, and when the acceleration detection unit does not detect the acceleration equal to or longer than the predetermined time interval, the shooting process is performed without image blur correction, or the shooting process is stopped. Is characterized by.

[0018]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. The correction optical device of the image blur correction camera according to the present invention is similar to that shown in FIG. FIG. 1 is a block diagram showing a first embodiment of an image blur correction camera according to the present invention. This image blur correction camera includes acceleration detection devices 1, 2, 3 and angular velocity detection devices 4, 5, 6. FIG. 2 shows the acceleration detection device 1,
It is a figure which shows one Embodiment of the mounting position of 2,3 and the angular velocity detection apparatus 4,5,6. The acceleration detection devices 1, 2, 3 and the angular velocity detection devices 4, 5, 6 are mounted in the camera body 15 and detect the acceleration in the three-axis directions and the angular velocity around the three axes, respectively. In the embodiment, the intersection of the film surface 16 and the optical axis 17 of the camera lens 14 is represented as the origin 18 of the orthogonal coordinates, the optical axis 17 of the camera lens 14 is represented as the Z axis, and the film surface 16 is represented as the XY plane.

The output values of the acceleration detecting devices 1, 2, 3 include
The acceleration generated by translational vibration and the gravitational acceleration are included. Further, since the camera posture changes due to the rotational vibration of the camera, the angle formed between the detection axis direction of the acceleration detection devices 1, 2 and 3 fixed to the camera coordinate system and the gravity acceleration direction changes. Therefore, the magnitude of the gravitational acceleration included in the output values of the acceleration detection devices 1, 2, 3 changes. Therefore,
The gravitational acceleration component is removed from the output values of the acceleration detection devices 1, 2 and 3, and the displacement is calculated using only the acceleration component generated by the translational vibration.

In order to calculate this gravitational acceleration component, the image blur correction camera is provided with a posture calculating means 9 and a gravitational acceleration component calculating means 10. As shown in FIG. 3, the attitude calculating means 9 calculates a coordinate conversion matrix T for converting from the inertial coordinate system 19 which is a stationary coordinate system to the camera coordinate system 20 which is a moving coordinate system. This coordinate conversion matrix T is calculated using the initial posture of the camera and the angular velocities around the three axes which are the outputs of the angular velocity detectors 4, 5, 6. This calculation method is a method used in a strapdown inertial navigation system and the like, and the details thereof are disclosed in, for example, Japanese Patent Laid-Open No. 2-309702.

First, the initial posture of the camera is obtained by utilizing the gravitational acceleration direction obtained from the outputs of the acceleration detecting devices 1, 2, 3. Here, since the camera has rotational vibration and translational vibration, the gravitational acceleration direction is continuously measured for an appropriate time, and the average of the measurement results is calculated to obtain the average gravitational acceleration direction. In this way, the average posture of the camera with respect to the inertial coordinate system is obtained from the direction of gravitational acceleration in the camera coordinate system, and this is set as the initial posture of the camera.

Equation 1 is a differential equation for calculating the coordinate transformation matrix T. Ω _C is obtained by substituting the angular velocities ω _X , ω _Y , and ω _Z around the X, Y, and Z axes, which are the outputs of the angular velocity detectors 4, 5, and 6, into Equation 1, and the initial posture of the camera is set to the initial condition. By solving the differential equation as, the coordinate transformation matrix T is calculated.

[0023]

[Equation 1]

The gravitational acceleration component computing means 10 multiplies the gravitational acceleration component in the inertial coordinate system by the coordinate conversion matrix T to obtain the gravitational acceleration component in camera coordinates. X-axis, which is the output value of the acceleration detection devices 1 and 2,
When this gravitational acceleration component is removed from the acceleration in the Y-axis direction, the acceleration generated by the translational vibration is obtained, and this value is further integrated to calculate the displacement of the translational vibration in the X-axis and Y-axis directions. On the other hand, the X-axis, which is the output value of the angular velocity detectors 4 and 5,
The angular velocity around the Y axis is integrated to calculate the rotation angle around the X axis and the Y axis.

Here, description will be made on the case where the calculation is performed without removing the gravity acceleration component and the case where the calculation is performed without removing the gravity acceleration component. FIG. 4 is a diagram showing a direction (assumed) of vibration generated in the camera. FIG.
(A) is the detection axis direction of the acceleration detection device 1, that is, X
An example of translational vibration in the axial direction is shown. FIG. 4 (B)
In addition to the translational vibration of FIG.
It shows an example in which it is rotationally oscillating about the Z-axis around.

FIG. 5 and FIG. 6 respectively show the acceleration detecting device 1 generated by the displacement of the translational vibration and the rotational vibration at this time.
5 is a graph showing a gravitational acceleration component in the detection axis (X axis) direction of FIG. Here, in order to simplify the explanation, the translational vibration and the rotational vibration are sinusoidal, and the amplitude and frequency of each are 0.8 mm, 2.0 Hz, 0.2 deg, 0.5
Hz. The gravity direction at this time is downward. In FIG. 4A, the X axis of the camera coordinate system is
Since the angle formed by the X-axis and the gravity direction does not change while remaining orthogonal to the gravity direction, the gravity acceleration component acting on the detection axis of the acceleration detection device 1 does not change and is 0. Therefore, the acceleration acting on the detection axis of the acceleration detecting device 1 is only the acceleration generated by the translational vibration. FIG. 7 is a graph showing the output of the acceleration detection device 1 at this time. FIG.
FIG. 8 is a graph showing a velocity obtained by integrating the acceleration of FIG. 7. Here, a method of integrating the acceleration and determining the initial velocity to calculate the velocity will be described later.

In FIG. 4B, the angle between the X axis of the camera coordinate system and the direction of gravity changes. Therefore, the acceleration acting on the detection axis of the acceleration detecting device 1 is the acceleration generated by the translational vibration including the gravitational acceleration component acting on the detecting axis of the acceleration detecting device 1. FIG. 9 and FIG. 10 are graphs showing the acceleration output of the acceleration detection device 1 at this time, respectively showing before the gravity acceleration component is removed and after the gravity acceleration component is removed. Also, FIG. 11 and FIG.
[Fig. 11] is a graph showing velocities obtained by integrating the accelerations of Figs. 9 and 10, respectively.

Since the translational vibration shown in FIG. 4B is the same as the translational vibration shown in FIG. 4A, the acceleration and velocity generated by the translational vibration in FIG. 4B are those shown in FIGS. Is equal to Therefore, when the gravitational acceleration component is removed,
It can be seen that accurate acceleration and velocity cannot be obtained if accurate acceleration and velocity are obtained and the gravitational acceleration component is not removed. FIG. 13 is a graph showing a velocity error when the gravitational acceleration component is not removed. From these, the translational displacement can be obtained by integrating the acceleration output after removal of the gravitational acceleration component. As described above, by removing the gravitational acceleration component, the acceleration generated by the translational vibration can be accurately calculated, and the translational vibration can be detected with high accuracy.

Next, a method of calculating the initial velocity will be described. Although the initial velocity cannot be theoretically obtained, the outputs of the acceleration detection devices 1 to 3 are due to camera shake, and therefore, the initial velocity is obtained on the assumption that the motion is periodic. In the present invention, as shown in the block diagram of FIG. 1, the acceleration is first integrated to obtain the velocity while the initial velocity remains undetermined, and the velocity is further integrated to obtain the displacement.
After that, the initial speed calculation unit 51 determines the initial speed and calculates the speed. FIG. 14 is a graph showing the output of the acceleration detection device 1. As described above, this acceleration is after the gravitational acceleration component has been removed. Since the output value contains noise as shown in (A) in the figure, noise is removed by using a low-pass filter, a high-pass filter, a moving average, etc., and an acceleration as shown in (B) in the figure is obtained. .

Then, as shown in FIG. 15, the maximum value (or the minimum value) of the acceleration is detected, and the acceleration for a predetermined number (time interval T) is cut out. Since the frequency of camera shake is generally about 1 to 15 Hz, 2 in this embodiment.
Assuming camera shake of Hz, the time interval T is set to 4 cycles (2 seconds). Next, the acceleration is cut out while the initial speed is undetermined, and the speed is calculated. Further, this velocity is integrated to calculate the displacement. When performing image blur correction of the camera, it is only necessary to obtain the relative displacement from the start of integration, and thus the initial displacement at the start of integration is unnecessary. That is, when the velocity is integrated to calculate the displacement, the integration constant is not necessary. Therefore, the initial displacement of the velocity is set to 0 and integrated to obtain the displacement. Then, the displacement at time t0 at time interval T and t1
The initial velocity (integral constant) is calculated assuming that the time displacement is equal. This is based on the assumption that the camera shake makes a periodic motion, as described above. FIG. 16 is a graph showing the speed thus calculated. As a result, the speed v1 at time t1 is obtained.

Next, in FIG. 17, if the shutter is opened from time t2 to t3, the speed v1 at time t1 is used as an initial condition to integrate the acceleration from time 1 to t2 to obtain the speed. As a result, the velocity v2 at the time t2 is obtained. Then, in FIG. 18, at time t
Acceleration is 2 with velocity v2 of 2 as initial velocity (integral constant)
Integrate twice to find the displacement from time t2 to t3. Since the displacement obtained at this time is a relative displacement, the displacement at time t2 is zero. By calculating as described above, the displacement during the shutter opening can be obtained from the acceleration before the shutter opening.

In the above description, the calculation method has been described according to the flow of time, but the actual shutter release time t2 is the time when the release button is pressed, so
It is not possible to predict the time t2 in advance. Therefore, the speed within that time is calculated in advance from the acceleration at the time interval T1,
Time interval T1 The last speed is stored. Then, if the release button is not pressed even after the lapse of a predetermined time, the time interval is extended or moved to move to the time interval T2 or T3.
The speed within that time is obtained from the acceleration of, and the speed at the last time of the time interval is stored. By repeating this, calculation is performed until the release button is pressed.

When the release button is pressed, the speed at the time when the release button is pressed (speed v2 at time t2 in FIG. 17) is calculated using the speed obtained immediately before (speed v1 at time t1 in FIG. 17). Then, using that as the initial speed, the displacement during shutter opening (from time t2 to t3 in FIG. 18)
Displacement).

By the way, when an inertial navigation system used in an aircraft or the like integrates acceleration to obtain a displacement, it takes a long time (a few minutes to a few hours) to obtain an acceleration. Error), the displacement error increases as time passes. In order to correct the image blur of the camera, it is necessary to accurately obtain the displacement during the shutter opening time. The time is 1 second or less (1/16 seconds or 1 /
4 seconds). For example, in order to suppress the displacement error caused by the initial velocity error to 10 μm in 1/4 second, the initial velocity error may be suppressed to 0.04 mm / s or less.

The object distance measuring means 7 (FIG. 1) uses a lens equipped with an encoder to measure the distance from the moving amount of the focusing lens to the object when the object is in focus. The photographing magnification detecting means 8 detects a magnification at the time of photographing by the camera.

The correction drive amount calculation means 11 calculates the drive amount of the correction lens 38 (FIG. 28) for correcting the image blur. The correction drive amount calculation means 11 calculates the displacement of the translational vibration in the X-axis and Y-axis directions calculated as described above, and X.
The motion of the camera that affects the image blur is obtained by the rotation angle about the axis and the Y-axis. Further, depending on the distance to the subject and the photographing magnification, the film surface 1 as shown in FIG.
The two-dimensional image blur amount on 6 is obtained. Next, using these signals, a signal for driving the correction lens 38 so as to cancel the image blur is calculated. Correction drive device 12
Drives the correcting lens 38 in accordance with this signal. As the correction driving device here, for example, JP-A-5-15
The one disclosed in Japanese Patent No. 8100 is known.

As described above, the acceleration detecting devices 1 and 2 are
By driving the correction lens 38 using a signal obtained by removing the gravitational acceleration component from the output value of, the image blur can be corrected without being affected by the gravitational acceleration component, and a clear image can be obtained. it can. Further, the displacement can be calculated by efficiently obtaining the initial speed at the start of integration.

Next, the calculation of the initial velocity and the control of the image blur correction will be described. FIG. 20 is a flowchart showing an embodiment of the timing of pressing the release button and the correction method at that time. In this example, for simplification, only one axial direction will be described. When the half-push switch is turned on in step 101, the process proceeds to step 102 and the acceleration detection device 1 is turned on. Then, in the next step 103, FIG.
As shown in, the maximum acceleration value (peak value) is detected. Then, in step 104, it is determined whether or not the full-press switch has been turned on. The maximum value of acceleration is detected until it is turned on, and when it is turned on in step 104, the process proceeds to step 105.

In step 105, it is determined whether or not the acceleration is detected for one cycle or more after the half-push switch is turned on until the full-push switch is turned on. When one cycle or more is detected, the routine proceeds to step 106, the initial velocity is obtained by the method described above, and the image blur correction operation is started at step 107. Then, after opening and closing the shutter in steps 108 and 109, the image blur correction operation is ended in step 110, and the acceleration detection device 1 is turned off in the next step 111.

On the other hand, in step 105, the acceleration is set to 1
If it is not detected for a period or more, it is not possible to calculate the speed and displacement thereafter, so control is performed so that image blur correction is not performed, and the shutters are opened and closed in steps 112 and 113.

21 to 23 are flowcharts showing a modification of FIG. 21 is the same as step 10
If the acceleration is not detected for one cycle or more before the full-press switch is turned on after the half-press switch is turned on in step 5, in step 114, a shooting prohibition display is displayed on the display unit (in the viewfinder) of the camera. This is done (the shooting process is not performed). Further, in the case of FIG. 22, when the acceleration is detected for one cycle or more in the same step 105 as described above, the process further proceeds to step 115, and it takes 2 seconds from when the half-push switch is turned on until the full-push switch is turned on. It is determined whether or not the above has passed. If 2 seconds or more has elapsed, the process proceeds to step 106 to perform image blur correction to perform shooting processing, and if 2 seconds or more has not passed to step 112 to perform image capture processing without image blur correction. I do.

Furthermore, in FIG. 23, the step 1
If two or more cycles are detected from the half-press switch being turned on to the full-press switch being turned on in step 15, step 1
In step 115, the initial velocity is calculated from the latest two cycles, and if two or more cycles are not detected in step 115, step 10 is performed.
6B, the initial velocity is calculated from one cycle. 22 and 23, like the one in FIG. 21, the photographing may be prohibited without performing the normal photographing process.

24 and 25 are block diagrams showing second and third embodiments of the image blur correction camera according to the present invention. Hereinafter, parts different from the image blur correction camera of FIG. 1 will be described. In FIG. 24, the posture detecting means 13 is provided without providing the acceleration detecting device 3. The posture detection means 13 detects the posture of the camera by detecting the direction of gravitational acceleration. Therefore, the attitude calculating means 9 includes the attitude detecting means 13 and the angular velocity detecting devices 4, 5, 5.
And the output of 6 are used to calculate the coordinate transformation matrix T.

If the acceleration detecting devices 1, 2, and 3 cannot detect static acceleration such as piezoelectric type,
Since the gravitational acceleration direction cannot be detected by the acceleration detecting devices 1, 2, 3, it is necessary to use the posture detecting means 13 as shown in FIG. In this case, the acceleration detecting device 3 that detects the acceleration in the Z-axis direction becomes unnecessary.

Further, in the case of FIG. 1, the two-dimensional image blur amount on the film surface 16 is obtained from the displacement of translational vibration in the X-axis and Y-axis directions and the rotation angle about the X-axis and Y-axis. Although the correction is performed, in the case of FIG. 25, the three-dimensional image blur amount is obtained from the displacement of the translational vibration in the Z-axis direction and the rotation angle around the Z-axis to perform the correction. Therefore, the gravitational acceleration component calculated by the gravitational acceleration component calculating means 10 is removed from the acceleration in the Z-axis direction, which is the output value of the acceleration detection device 3, and this value is integrated to determine the displacement of the translational vibration in the Z-axis direction. It is calculated and transmitted to the correction drive amount calculation means 11. Further, the angular velocity around the Z-axis, which is the output value of the angular velocity detection device 6, is integrated to calculate the rotation angle around the Z-axis, which is transmitted to the correction drive amount calculation means 11.

At this time, as a method of correcting the focus shift due to the displacement of the translational vibration in the Z-axis direction, for example, a focusing lens 37 used in autofocus (see FIG. 2).
8) can be driven in the Z-axis direction. Further, as a method of correcting the image blur caused by the rotational vibration around the Z axis, there are a method of rotating the image pickup surface and a method of using an image rotator, for example.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications such as the following are possible within an equivalent range. (1) For example, although the acceleration detection devices 1, 2, 3 and the angular velocity detection devices 4, 5, 6 are mounted inside the camera body 15, they may be mounted inside the camera lens 14. Further, the acceleration detection devices 1, 2, and 3 may be replaced with one three-dimensional acceleration detection device, as long as they can detect accelerations in the three axis directions.

(2) In the embodiment, the image blur is corrected by driving the correction lens 38, but the image blur may be corrected by driving a film, for example. In the case of a video camera, either the correction lens 38 or the image pickup device may be driven.

(3) Further, in FIG. 1 or 25, the posture calculation means 9 uses the direction of gravitational acceleration in the camera coordinate system obtained from the outputs of the acceleration detection devices 1, 2 and 3 to determine the initial posture of the camera. However, the method of obtaining the initial posture of the camera is not limited to this method. For example, the camera may be placed in a certain posture (horizontal, vertical, etc.), and the posture at this point may be recognized by the camera by pressing a button or the like, and this may be set as the initial posture of the camera.

(4) In FIG. 20, etc., in this embodiment, the acceleration detection device 1 is turned on after the half-push switch is turned on in order to save power consumption. However, the present invention is not limited to this. It may be after the power switch is turned on. (5) Further, in FIG. 20, in the case of the biaxial acceleration detecting devices 1 and 2, when the X axis is one cycle or more and the Y axis is less than one cycle, the Y axis does not satisfy the condition, and thus the image blur is not satisfied. The correction may not be performed. Further, in FIG.
When the X-axis has two cycles or more and the Y-axis has one cycle or more and less than two cycles, the initial speed is calculated from two cycles for the X-axis and the initial speed is calculated from one cycle for the Y-axis. good.

(6) In FIGS. 20 to 23, "2
The conditions of “second”, “1 cycle”, and “2 cycle” are not limited to these. In order to detect the image blur amount with high accuracy, it is desirable to use acceleration of 4 cycles or more for initial velocity calculation. (7) For a video camera with a long shooting time, at a certain time during shooting, the speed can be calculated from the acceleration for a predetermined time before that time, and the displacement can be calculated using that as the initial speed. Is. By repeating this, the accumulated displacement error can be reduced.

[0052]

According to the first aspect of the present invention, the image blur correction can be performed by efficiently obtaining the initial velocity from the acceleration acting on the camera. Further, according to the inventions of claims 2 to 5, the initial velocity and displacement of the translational vibration are calculated by using the acceleration output from which the gravitational acceleration component is removed, and the image blur (claim 4).
In the invention, since the image blur and the focus shift are corrected, even if the gravitational acceleration component acting on the detection axis of the acceleration detecting means changes due to the rotational vibration, the image blur (according to claim 4) is accurately performed. According to the invention, it becomes possible to correct image blur and focus shift, and a clear image can be obtained.

According to the sixth aspect of the present invention, it is possible to save the power consumption of the calculation units such as the acceleration detection unit and the speed calculation unit. According to the invention of claim 7 or claim 8, whether or not the image blur correction is to be performed is determined according to the acceleration detection time or the like by the acceleration detector, so that the image blur correction can be accurately performed. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of an image blur correction camera according to the present invention.

FIG. 2 is a diagram showing an embodiment of mounting positions of acceleration detection devices 1, 2, and 3 and angular velocity detection devices 4, 5, and 6.

FIG. 3 is a diagram showing an inertial coordinate system 19 which is a stationary coordinate system and a camera coordinate system 20 which is a moving coordinate system.

FIG. 4 is a diagram showing directions of vibrations generated in the camera.

FIG. 5 is a graph showing a displacement of translational vibration.

FIG. 6 is a graph showing a gravitational acceleration component in the detection axis (X axis) direction of the acceleration detection device 1 caused by rotational vibration.

FIG. 7 is a graph showing an output of the acceleration detection device 1.

FIG. 8 is a graph showing speed.

FIG. 9 is a graph showing an acceleration output (before removal of a gravitational acceleration component) of the acceleration detection device 1.

FIG. 10 is a graph showing acceleration after removal of a gravitational acceleration component.

FIG. 11 is a graph showing a velocity obtained from acceleration before removal of a gravitational acceleration component.

FIG. 12 is a graph showing a velocity obtained from acceleration after removal of a gravitational acceleration component.

FIG. 13 is a graph showing a velocity error when the gravitational acceleration component is not removed.

FIG. 14 is a graph showing an output of the acceleration detection device 1.

FIG. 15 is a graph showing a state in which the maximum value of the acceleration of FIG. 14 is detected and the acceleration of the time interval T is cut out.

16 is a graph showing a velocity calculated from the acceleration of FIG.

FIG. 17 is a graph showing speeds after time t1.

FIG. 18 is a graph showing the displacement from time t2 to time t3.

FIG. 19 is a diagram showing an image blur on the film surface 16.

FIG. 20 is a flowchart showing an embodiment of the timing of pressing the release button and the correction method at that time.

FIG. 21 is a flowchart showing a modified example of FIG.

22 is a flowchart showing a modified example of FIG.

FIG. 23 is a flowchart showing a modified example of FIG.

FIG. 24 is a block diagram showing a second embodiment of an image blur correction camera according to the present invention.

FIG. 25 is a block diagram showing a third embodiment of an image blur correction camera according to the present invention.

FIG. 26 is a block diagram showing a first example of a conventional image blur correction camera.

FIG. 27 is a block diagram showing a second example of a conventional image blur correction camera.

FIG. 28 is a schematic configuration diagram of a correction optical device of a conventional image blur correction camera.

[Explanation of symbols]

 1,2,3 Acceleration detection device (X, Y, Z axis directions) 4, 5, 6 Angular velocity detection device (around X, Y, Z axes) 7 Subject distance measurement means 8 Imaging magnification detection means 9 Attitude calculation means 10 Gravity Acceleration component calculation means 11 Correction drive amount calculation means 12 Correction driving device 13 Attitude detection means 14 Camera lens 15 Camera body 16 Film surface 21 Subject 22 Lens 34 Lens with image blur correction function 35 Camera 36 Fixed lens 37 Focusing lens 38 For correction Lens 51 Initial speed calculator

Claims (8)

[Claims] 1. An acceleration detecting section for detecting an acceleration acting on a camera, and among accelerations detected by the acceleration detecting section between a first peak value time and a last peak value time in a predetermined time interval. Using the acceleration, a speed calculation unit that calculates the speed from the acceleration by assuming that the displacement of the camera at the time of the first peak value and the displacement of the last peak value are equal, and from the speed calculated by the speed calculation unit A displacement calculation unit that calculates a displacement during image blur correction; and a correction lens and / or an imaging surface that calculates an image blur amount based on the displacement calculated by the displacement calculation unit and cancels the image blur amount. An image blur correction camera, comprising: a correction drive amount calculation unit that calculates a drive amount of the correction lens; and a correction drive unit that drives the correction lens and / or the imaging surface. 2. An acceleration detector for detecting acceleration in the three-axis directions acting on the camera, an angular velocity detector for detecting angular velocities around the three axes acting on the camera, an initial posture of the camera with respect to a stationary coordinate system, and the three axes. A posture calculation unit that calculates a coordinate conversion matrix between a camera coordinate system and a stationary coordinate system from an angular velocity about an axis, and a gravity acceleration component calculation that calculates a gravity acceleration component in the camera coordinate system using the coordinate conversion matrix. Part and acceleration from which the gravitational acceleration component has been removed, using the acceleration from the first peak value to the last peak value in a predetermined time interval, using the first peak value and the last peak value. A velocity calculation unit that calculates a velocity from the acceleration by assuming that the displacements of the cameras are equal to each other; , A displacement calculation unit that calculates the displacement during image blur correction, a subject distance measurement unit that measures the distance between the camera and the subject, a shooting magnification detection unit that detects the shooting magnification of the camera, X-axis and Y-axis Direction or triaxial displacement, X axis and Y
X-axis and Y calculated from the angular velocity around the axis or around three axes
An image blur amount is calculated based on a rotation angle about an axis or about three axes, a distance between the camera and a subject, and the photographing magnification, and a correction lens and / or an imaging surface is driven to cancel the image blur amount. An image blur correction camera, comprising: a correction drive amount calculation unit that calculates an amount; and a correction drive unit that drives the correction lens and / or the imaging surface. 3. An acceleration detecting section for detecting accelerations in the X-axis and Y-axis directions acting on the camera, an angular velocity detecting section for detecting angular velocities around the three axes acting on the camera, and detecting a gravitational acceleration direction. A posture detection unit that detects a posture of the camera; a posture calculation unit that calculates a coordinate transformation matrix between a camera coordinate system and a stationary coordinate system based on the posture of the camera and the angular velocities about the three axes; A gravitational acceleration component calculation unit that calculates a gravitational acceleration component in the camera coordinate system using a matrix, and among accelerations from which the gravitational acceleration component is removed, from a first peak value to a last peak value in a predetermined time interval. Using accelerations between and between the accelerations by assuming equal camera displacements at the first and last peak values. A speed calculation unit that calculates, a displacement calculation unit that calculates the displacement during image blur correction from the speed calculated by the speed calculation unit, and a subject distance measurement unit that measures the distance between the camera and the subject, A photographing magnification detection unit that detects a photographing magnification of the camera; a displacement angle in the X-axis and Y-axis directions; a rotation angle around the X-axis and the Y-axis calculated from an angular velocity around the X-axis and the Y-axis; A correction drive amount calculation unit that calculates an image blur amount based on the distance between the two and the shooting magnification, and calculates the drive amount of the correction lens and / or the imaging surface to cancel the image blur amount; An image blur correction camera, comprising: a lens and / or a correction drive unit that drives the imaging surface. 4. An acceleration detecting section for detecting accelerations in three-axis directions acting on the camera, an angular velocity detecting section for detecting angular velocities around the three axes acting on the camera, an initial posture of the camera with respect to a stationary coordinate system, and the three axes. A posture calculation unit that calculates a coordinate conversion matrix between a camera coordinate system and a stationary coordinate system from an angular velocity about an axis, and a gravity acceleration component calculation that calculates a gravity acceleration component in the camera coordinate system using the coordinate conversion matrix. Part and acceleration from which the gravitational acceleration component has been removed, using the acceleration from the first peak value to the last peak value in a predetermined time interval, using the first peak value and the last peak value. A velocity calculation unit that calculates a velocity from the acceleration by assuming that the displacements of the cameras are equal to each other; , A displacement calculation unit that calculates the displacement during image blur correction, a subject distance measurement unit that measures the distance between the camera and the subject, a shooting magnification detection unit that detects the shooting magnification of the camera, and Displacement, rotation angle about three axes calculated from angular velocity about three axes, distance between the camera and the subject,
And an image blur amount and a focus shift amount are calculated based on the photographing magnification, and at least one driving amount of a correction lens, an imaging surface, or a focusing lens is calculated to cancel the image blur amount and the focus shift amount. An image blur correction camera, comprising: a correction drive amount calculation unit that performs the correction drive amount calculation; and a correction drive unit that drives at least one of the correction lens, the imaging surface, and the focusing lens. 5. The image blur correction camera according to claim 2, wherein the posture calculation unit is a camera relative to a stationary coordinate system from a gravity acceleration direction in a camera coordinate system obtained from acceleration in the three axis directions. An image blur correction camera characterized by calculating an initial posture of the camera. 6. The image blur correction camera according to any one of claims 1 to 5, wherein the acceleration detection unit is turned on after a half-push switch of the camera is turned on, and then until a full-push switch is turned on. An image blur correction camera characterized by calculating the speed from the acceleration of the camera. 7. The image blur correction camera according to claim 1, wherein the speed calculation unit determines the speed when the acceleration detection unit detects acceleration of one cycle or more. An image blur correction camera, wherein the image blur correction camera performs a photographing process without performing the image blur correction or stops the photographing process when the acceleration detection unit does not detect acceleration of one cycle or more. 8. The image blur correction camera according to claim 1, wherein the speed calculation unit is configured to, when the acceleration detection unit detects acceleration of the predetermined time interval or more. When the acceleration is calculated and the acceleration detecting unit does not detect the acceleration over the predetermined time interval, the image capturing process is performed without image blur correction, or the image capturing process is stopped. Anti-shake camera.