JPH11271831A - Interchangeable lens and shake correction camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interchangeable lens and a shake correction camera capable of accurately calculating shake amount in accordance with photographing circumstances. SOLUTION: Whether or not photographic image magnification β is larger than a threshold B is judged in S203. When the magnification β is equal to or under the threshold B, angular shake by which the optical axis of a photographing optical system is inclinend occupies most of the factor of the shake. Therefore, the shake amount D1 on an image surface is calculated considering only the angular shake. Meanwhile, when the magnification β is larger than the threshold B, parallel shake by which the optical axis is displaced in parallel can not be neglected as the factor of the shake. Therefore, displacing amount dY caused by the parallel shake is calculated in S204, and the shake amount Di on the image surface is calculated considering the angular shake and the parallel shake. As a result, the shake amount is accurately calculated in accordance with the magnification β.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an interchangeable lens and a shake correction camera equipped with a shake correction device for correcting shake such as camera shake.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 2-66535 discloses a blur correction device that detects a change in the angle of an optical axis due to a camera shake of a photographing device and corrects the camera shake.

Japanese Patent Application Laid-Open No. 3-46642 discloses a first angular velocity sensor for detecting an angular velocity about a first axis orthogonal to an optical axis of a photographing optical system, and a second angular velocity sensor for detecting an angular velocity about a second axis orthogonal to the first axis. A second angular velocity sensor for detecting the angular velocity of the first, the first acceleration sensor for detecting the acceleration in the first axial direction, the second acceleration sensor for detecting the acceleration in the second axial direction, the first and the second A rotation mechanism for driving the optical system to rotate about an axis 2;
FIG. 1 discloses a shake correction device including a servo circuit that drives and controls a rotation mechanism based on output signals of first and second angular velocity sensors and output signals of first and second acceleration sensors. doing. This blur correction device uses both an angular velocity sensor and an acceleration sensor in order to prevent blurring during close-up shooting with a short shooting distance.

[0004]

Problems to be Solved by the Invention
The shake correction device disclosed in Japanese Patent Application Laid-Open Publication No. H10-209400 constitutes a shake vibration detection system using an angular velocity sensor and an acceleration sensor as sensors for detecting shake. This image stabilizer is
Two types of sensors having different detection characteristics detect blurring vibrations having different characteristics, and improve image stabilization performance by correcting image blurring. However, the shake correction device has a problem that the amount of calculation increases when calculating the amount of shake based on the output signals of these sensors due to the large number of sensors.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an interchangeable lens and a shake correction camera capable of accurately calculating a shake amount according to a shooting situation.

[0006]

The present invention solves the above-mentioned problems by the following means. In addition, in order to make it easy to understand, description is given with reference numerals corresponding to the embodiment of the present invention, but the present invention is not limited to this. That is, the invention according to claim 1 is an interchangeable lens that can be mounted on a camera body, wherein a parallel shake detection unit (8) that detects a shake that translates an optical axis (O) of a photographing optical system, and the optical axis. An angle shake detection unit (7) for detecting a shake that tilts the camera, and a calculation unit (6) for calculating the amount of shake, wherein the calculation unit includes the parallel shake detection unit and the parallel shake detection unit according to a subject distance or a photographed image magnification. And / or based on the output signal of the angle blur detection unit,
This is an interchangeable lens characterized by calculating a blur amount (S206).

According to a second aspect of the present invention, in the interchangeable lens according to the first aspect, the calculating section is configured to determine whether the subject distance is longer than a predetermined distance or when the photographed image magnification is smaller than the predetermined magnification. An interchangeable lens characterized in that a shake amount is calculated based only on an output signal of the angle shake detection unit.

[0008] The invention of claim 3 is claim 1 or claim 2.
In the interchangeable lens described in the above, when the subject distance is shorter than a predetermined distance, or when the photographed image magnification is larger than the predetermined magnification, the arithmetic unit outputs the parallel blur detection unit and the output signal of the angle blur detection unit. This is an interchangeable lens that calculates a shake amount based on the calculated amount.

[0009] The invention of claim 4 is the invention of claims 1 to 3.
In the interchangeable lens according to any one of the above, when the object distance is longer than a predetermined distance, or when the photographed image magnification is smaller than the predetermined magnification, the calculation unit outputs the parallel blur detection signal to the output signal of the parallel shake detection unit. This is an interchangeable lens characterized in that the calculation based on it is stopped.

[0010] The invention of claim 5 is the invention of claims 2 to 4.
The interchangeable lens according to any one of the above, further comprising a variable setting section (20) for variably setting the predetermined distance or the predetermined magnification to a predetermined value.

[0011] The invention of claim 6 is the invention of claims 1 to 5.
In the interchangeable lens according to any one of the above, the shake correcting optical system (1) for correcting shake, a driving unit (2) for driving the shake correcting optical system, and the driving according to the shake amount. A control unit (6) for driving and controlling the unit, wherein the parallel shake detection unit includes an acceleration detector (8) for detecting acceleration.
Wherein the angular blur detector is an angular velocity detector (7) for detecting an angular velocity.

A seventh aspect of the present invention is a parallel blur detecting section (8) for detecting a blur that shifts the optical axis (O) of the photographing optical system in parallel, and an angle blur detecting section (the shake detecting section) for detecting a blur that tilts the optical axis. 7) and a shake correction optical system (1) for correcting shake
A drive unit (2) for driving the shake correction optical system, a calculation unit (6) for calculating the shake amount, and
A control unit (6) for controlling the driving of the driving unit, wherein the calculation unit is configured to output the parallel shake detection unit and / or the angle shake detection unit based on an output signal of the parallel shake detection unit according to a subject distance or a captured image magnification. And a shake correction camera that calculates a shake amount (S206).

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a first embodiment of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a block diagram of the shake correction camera according to the first embodiment of the present invention.

An image stabilizing camera according to a first embodiment of the present invention includes an image stabilizing optical system 1, a driving unit 2, and a position detecting unit 3.
A main CPU 4, a blur correction CPU 6, an angular velocity sensor 7, an acceleration sensor 8, a distance encoder 9,
It includes a lens information ROM 10, a switching unit 20, and a signal processing circuit (not shown) that processes these output signals.

The blur correction optical system 1 is an optical system that constitutes at least a part of the photographing optical system and changes the optical path of the photographing optical system. The blur correction optical system 1 is, for example, a blur correction lens that optically shifts an image to correct blur by driving in a direction substantially orthogonal to the optical axis.

The driving section 2 drives the blur correction optical system 1. The driving unit 2 is, for example, a voice coil motor that drives the blur correction optical system 1 in a direction substantially orthogonal to the optical axis by an electromagnetic driving method. The drive unit 2 includes a motor that drives the blur correction optical system 1 in the x-axis direction and a motor that drives the blur correction optical system 1 in the y-axis direction.

The position detecting section 3 detects the position of the blur correction optical system in a plane substantially perpendicular to the optical axis.
The position detection unit 3 includes, for example, a light emitting element (IRED), a slit member attached to the blur correction optical system 1 for limiting a light beam incident from the IRED, and a light receiving element (PSD) to which a light beam passing through the slit member enters. ). The position detection unit 3 detects the position of the light that moves on the PSD as the slit member moves, and outputs drive position information of the shake correction optical system 1 to the shake correction CPU 6. The position detection unit 3 includes a device for detecting the position of the blur correction optical system 1 in the x-axis direction and a device for detecting the position in the y-axis direction.

The main CPU 4 is a central processing unit for controlling the entire camera. The main CPU 4 selects whether or not to perform a blur correction operation based on information output from the blur correction CPU 6, information on a power supply capacity (not shown), and outputs command information regarding start of blur correction and stop of blur correction. , To the blur correction CPU 6.

The blur correction CPU 6 calculates a blur amount (a blur correction amount) on the image plane based on vibration detection information output from the angular velocity sensor 7 and the acceleration sensor 8, position detection information output from the position detector 7, and a subject distance. ) Is a central processing operation unit. The shake correction CPU 6 controls the drive of the drive unit 2 based on the shake correction amount. The shake correction CPU 6 includes an angular velocity sensor 7 and an acceleration sensor 8.
From the output signal, a DC component that causes a calculation error of the blur amount is removed. Further, the blur correction CPU 6 calculates a subject distance, a lens position, and a photographic image magnification based on the output signal of the distance measuring encoder 9 and the lens information read from the lens information ROM 10. The blur correction CPU 6 includes:
Drive unit 2, position detection unit 3, main CPU 4, angular velocity sensor 7, acceleration sensor 8, distance measuring encoder 9,
, A lens information ROM 10 and a switching unit 20 are connected. The blur correction CPU 6 can communicate with the main CPU 4.

FIG. 2 is a graph showing the ratio of the blur factor to the subject distance. FIG. 3 is a graph showing a ratio of a blur factor to a photographed image magnification. The blur includes a blur caused by rotation about an X axis or a Y axis perpendicular to the optical axis (hereinafter, referred to as angle shake) and a shake caused by displacement in the X axis or Y axis direction (hereinafter, referred to as parallel shake). I do. FIG.
FIG. 3 and FIG. 3 schematically show the results of substituting the typical values of the angular blur and the parallel blur, respectively, assuming an imaging optical system having a certain focal length. In FIG.
The horizontal axis indicates the subject distance, and the vertical axis indicates the ratio of the factors of the angular blur and the parallel blur to the blur amount on the image plane (film surface). In FIG. 3, the horizontal axis represents the magnification of the photographed image, and the vertical axis represents the ratio of the factors of the angular blur and the parallel blur in the blur on the image plane.

As shown in FIG. 2, when the subject distance (photographing distance) is far, most of the causes of blurring are due to angular blurring. When the photographing distance is infinity, theoretically all It is angle blur. Also, as shown in FIG. 3, when the photographed image magnification is low, the cause of the blur is almost entirely due to the angle blur, and the angle blur is based on the output signal of the angular velocity sensor 7 and the amount of change in the angle is calculated. It can be obtained by calculation. On the other hand, when the subject distance (photographing distance) becomes short and the photographing image magnification increases, the proportion of parallel blurring increases, so that the cause of parallel blurring as well as angle blurring cannot be ignored. As described above, since the ratio of the cause of the blur differs depending on the subject distance or the photographed image magnification, in the embodiment of the present invention, the blur correction device is configured by combining two types of sensors that detect different physical quantities. doing.

The angular velocity sensor 7 shown in FIG. 1 is a sensor having a characteristic of detecting an angular shake that tilts the optical axis. The angular velocity sensor 7 is, for example, a vibration gyro-type angular velocity sensor that detects an angular velocity around an axis orthogonal to the optical axis. The angular velocity sensor 7 includes a pitching detection sensor that detects an angular velocity about the X axis orthogonal to the optical axis, and a yawing detection sensor that detects an angular velocity about the Y axis orthogonal to the optical axis. . The angular velocity sensor 7 includes a processing circuit (not shown) that processes the detected vibration detection information (angular velocity signal).

The acceleration sensor 8 is a sensor having a characteristic different from that of the angular velocity sensor 7, and has a characteristic of detecting a parallel shake which is translated in the optical axis direction.
The acceleration sensor 8 is, for example, a piezoresistive, capacitive or piezoelectric acceleration sensor that detects acceleration in a direction orthogonal to the optical axis. The acceleration sensor 8 includes an X-axis detection sensor for detecting X-axis acceleration and a Y-axis acceleration for detecting vibrations in two independent directions at least in a plane orthogonal to the optical axis. And a Y-axis detection sensor for detecting. The acceleration sensor 8 includes a processing circuit (not shown) that processes detected vibration detection information (acceleration signal).

The distance measuring encoder 9 is an encoder that detects a distance to a subject and outputs a signal (subject distance information) proportional to the subject distance as a pulse signal. The distance measuring encoder 9 outputs the detected subject distance information to the blur correction CPU 6.

The lens information ROM 10 stores focal length information relating to the focal length, information unique to the lens, coefficients for converting a pulse signal output from the distance measuring encoder 9 into physical quantities required for calculation, and the like. . The lens information ROM 10 stores in advance a photographed image magnification corresponding to a combination of the focal length and the subject distance as a table, and the blur correction CPU 6 reads out a value corresponding to the combination.

The switching unit 20 allows the photographer to change the threshold value which is used as a reference for calculating the amount of blur considering only the angular blur or calculating the amount of blur considering the angular blur and the parallel blur. Is set. The switching unit 20 is a dial-type changeover switch that continuously changes the threshold value from the shortest to the longest object distance illustrated in FIG. 2 or from the large to the small captured image magnification illustrated in FIG. 3. is there. Further, the switching unit 20 may be a slide switch that switches the threshold value to a plurality of stages.

FIG. 4 is a block diagram showing a calculation process in a case where the shake amount is calculated in consideration of only the angle shake in the camera according to the first embodiment of the present invention. FIG.
FIG. 5 is a block diagram showing a calculation process when calculating a shake amount in consideration of an angle shake and a parallel shake in the shake correction camera according to the first embodiment of the present invention. In addition, FIG.
It is a diagram showing an operation process of the shake amount D _i for 1 axis angular velocity, FIG. 5 is a diagram showing an operation process of the shake amount D _i for 1 about the axis of the angular velocity and uniaxial direction of the acceleration.

As shown in FIG. 5, the CPU 6 for blur correction includes an integrating section 61, an angular displacement converting section 62, and an integrating section 6.
3, 64, a parallel displacement amount calculating section 65, and a photographed image magnification multiplying section 66.

The integrator 61 calculates the amount of angular fluctuation dθ based on the angular velocity signal ω in the pitch or yaw direction output from the angular velocity sensor 7. The integrator 61 corrects the angular velocity signal ω so that the angular velocity zero value becomes the center of the output, and then multiplies the angular velocity signal ω by the unit time dt for each unit time dt to obtain an angular variation dθ with respect to the optical axis. Is calculated. As shown in FIG. 4, when considering only the angular shake, the integration unit 61 outputs the angle variation dθ to the angle displacement conversion unit 62. In addition, as shown in FIG. 5, when considering the angular blur and the parallel blur, the integrator 61 outputs the angle variation dθ to the angle displacement converter 62 and the parallel displacement calculator 65.

The angular displacement converter 62 calculates an angle blurring amount Dθ (hereinafter, θ of Dθ is a suffix) based on the angle fluctuation amount dθ calculated by the integrating unit 61. Angular displacement transducer 62, as shown in FIG. 4, when considering only the angle blur outputs the angular shake amount Dθ as shake amount D _i in the image plane.

The integrators 63 and 64 integrate the acceleration signal α output from the acceleration sensor 8 twice for each unit time dt.
The displacement amount d _Y per unit time dt is calculated. The integration units 63 and 64 output the displacement amount d _Y to the parallel displacement amount calculation unit 65.

The parallel displacement calculating section 65, an angle variation amount dθ the integral unit 61 is calculated, the integration section 63 and 64 on the basis of the displacement amount d _Y computed calculates the displacement amount d _p by parallel shake Things. The parallel displacement calculator 65 outputs the displacement d _p due to the parallel blur to the photographed image magnification multiplier 66.

The photographed image magnification multiplying section 66 includes a lens information RO.
A photographing magnification β read from M10, by multiplying the displacement amount d _p by parallel motion, and thereby calculates the parallel shake amount D _para. The photographed image magnification multiplying unit 66 outputs the parallel blur amount _Dpara to the angular displacement converting unit 62. Image stabilization CPU
6 is the angle blur amount Dθ calculated by the angle displacement conversion unit 62
And the parallel blur amount D _para calculated by the photographing image magnification multiplying unit 66.
Based on the bets, it calculates the shake amount D _i in the image plane.

Next, a description will be given of a process of calculating a shake amount by the shake correction camera according to the first embodiment of the present invention. FIG.
5 is a flowchart illustrating a process of calculating a blur amount by the shake correction camera according to the first embodiment of the present invention. In step (hereinafter, referred to as S) 200, the blur correction CPU 6 acquires focal length information and subject distance information. The blur correction CPU 6 calculates the subject distance based on the focal length information of the photographing optical system read from the lens information CPU 10 and the output signal of the distance measuring encoder 9.
Further, the blur correction CPU 6 reads out the photographed image magnification from the lens information CPU 10.

In step S201, the CPU 6 for blur correction
Acquires the photographed image magnification β. The photographed image magnification β is determined by the combination of the subject distance and the focal length, and the blur correction CPU 6 reads a value corresponding to these combinations from the table of the lens information ROM 10 as the photographed image magnification β.

In step S202, the CPU 6 for blur correction
Calculates the angle variation dθ. As shown in FIGS. 4 and 5, the integrator 61 calculates the amount of angular change dθ based on the angular velocity signal ω output from the angular velocity sensor 7.

In S203, the CPU 6 for blur correction
Determines whether the absolute value of the photographed image magnification β is larger than the threshold value B. When the magnification β of the captured image is smaller than 1/30, most of the causes of the camera shake vibration can be considered to be caused by the angular shake vibration. The blur correction CPU 6 presets the absolute value of the threshold value B as a reference for determining whether to calculate the displacement amount d _Y to, for example, 1/30. When the absolute value of the photographed image magnification β is larger than the threshold value B, the process proceeds to S204, and when the absolute value of the photographed image magnification β is equal to or smaller than the threshold value B, the process proceeds to S205.

In step S204, the CPU 6 for blur correction
Calculates the displacement d _Y. When the absolute value of the photographed image magnification β is greater than the threshold value B, as shown in FIG. As shown in FIG. 5, the integration units 63 and 64
Calculates the displacement amount d _Y based on the acceleration signal α output by.

In step S205, the CPU 6 for blur correction
Calculates the shake amount D _i in the image plane. Stabilizer C
When the PU 6 determines that the absolute value of the photographed image magnification β is equal to or smaller than the threshold value B, as shown in FIG. 3, the cause of the blur can be considered to be almost entirely caused by the angular blur. Motion compensation CPU6, considering only the angle shake, and calculates the shake amount D _i in the image plane. The angle displacement conversion unit 62 calculates the amount of angular shake Dθ by the following equation (1).

[0040]

(Equation 1)

Where β is the magnification of the photographed image and θ is
This is the blur angle, and l is the subject distance. As shown in FIG. 4, the angular displacement conversion unit 62 calculates the blur amount D on the image plane.
_The angle fluctuation amount Dθ is output as _i .

On the other hand, if the blur correction CPU 6 determines that the absolute value of the photographed image magnification β is larger than the threshold value B, as shown in FIG. Disappears. Motion compensation CPU6 calculates the shake amount D _i in the image plane summarizes the angular shake and parallel shake. The parallel displacement amount calculation unit 65 calculates the displacement amount d _p due to the parallel shake, and the photographed image magnification multiplication unit 66 calculates the parallel shake amount D _para by the following equation (2).

[0043]

(Equation 2)

Here, d _p is the displacement amount (parallel blurring amplitude) due to parallel blurring. Motion compensation CPU6 is the shake amount D _i in the image plane is the sum of these shake amount, including angular shake amount Dθ and parallel shake amount D _para, calculates the number 3 shown below.

[0045]

(Equation 3)

[0046] Here, the ratio occupied by the angle shift amount Dθ for the shake amount D _i in the image plane Pshita (the θ of Pshita a subscript) is as shown in the equation (4) below.

[0047]

(Equation 4)

As shown in equation (4), when the subject distance is infinity, in principle, the cause of blur is angular blur, but as the subject distance becomes closer, the proportion of parallel blur increases. . In the first embodiment of the present invention, a blur correction device is configured by combining two types of sensors that detect different physical quantities. Then, motion compensation CPU6 is shooting magnification β becomes the close object distance is at greater than the threshold value B, taking into account the angular shake and parallel shake calculates the shake amount D _i. On the other hand, the blur correction CPU
6 indicates that the subject distance is long and the photographed image magnification β is equal to the threshold B
When the angle is less than or equal to,
Calculate _i .

Next, a method of calculating the amount of blur will be described for a case where the angle changes with respect to the optical axis and a case where a parallel change occurs in addition to the angle change. FIG. 7 is a diagram for explaining the amount of blur when the angle changes with respect to the optical axis. a
Is a distance from the photographing object S to the front main plane H of the photographing optical system G. b is the distance from the rear principal plane H ′ of the photographing optical system G to the image plane I. T is the distance from the front main plane H to the rear main plane H ′ (the thickness of the imaging optical system G).
R is the distance from the object S to the image plane I. In addition,
The relationship shown in the following Expression 5 holds for the distance R.

[0050]

(Equation 5)

Here, a minute time dt is set for a stationary subject.
In the meantime, it is assumed that the camera changes by an angle variation dθ about a certain point N on the optical axis. n is the distance from the rotation center N to the image plane I. In this case, the subject can be considered to have changed by the amount of angle variation −dθ about the point N, assuming the optical axis of the camera as a reference. D _O is the amount of movement of the subject due to this change. −dφ is a change amount of the incident angle of the subject light to the photographing optical system G, and is as shown in the following Expression 6.

[0052]

(Equation 6)

[0053] angular displacement transducer 62, a shake amount D _i in the image plane can be calculated by the following equation 7 from the relationship of the imaging.

[0054]

(Equation 7)

(When Angle Change and Parallel Change Occur) FIG. 8
FIG. 7 is a diagram for explaining a blur amount when a parallel change occurs in the optical axis in addition to an angle change. L is, for example, the distance from the acceleration sensor 8 mounted in the lens barrel to the image plane I. d _Y is the displacement amount from the point P0 to the point P1 calculated by integrating the acceleration signal α output from the acceleration sensor 8 by the second order. As shown in FIG. 8, when the camera moves in parallel by the displacement d _p during the short time dt from time t0 to time t1, and further changes the angle by the angle change dθ,
The acceleration sensor 8 is displaced from the point P0 to the point P1 during the short time dt. The displacement d _Y can be regarded as linear when the angle change d θ is small.

FIG. 9 is a diagram for explaining a method of calculating the amount of parallel movement. The displacement d _Y is the sum of the displacement due to the angular shake and the displacement d _p due to the parallel shake, and the displacement d
_The following relationship is established between _Y , the angle change amount dθ, and the displacement amount d _p due to parallel shake.

[0057]

(Equation 8)

The parallel displacement calculator 65 calculates the angle change dθ.
Is small, the displacement d _p due to the parallel shake is
It is calculated by the following equation (9).

[0059]

(Equation 9)

The photographic image magnification calculation unit 66 calculates the photographic image magnification β by adding the displacement d _p due to parallel blurring as shown in the following Expression 10.
To calculate the parallel blur amount D _para on the image plane.

[0061]

(Equation 10)

Shake amount D _i in [0062] image plane, the short time dt
Is the sum of the angular shake amount Dθ and parallel shake amount D _para between. Motion compensation CPU6 is the following Equation 11, and calculates a blurring amount D _i in the image plane.

[0063]

[Equation 11]

The thickness T, distance b and focal length f of the photographing optical system G can be calculated based on the pulse signal of the distance measuring encoder 9 and the lens information stored in the lens information ROM 10. The remaining variables a and R can be calculated by Newton's imaging formula. Thus, the blur correction for CPU6 calculates the number 5 to number 11 of the shake amount D _i in the image plane.

The camera according to the first embodiment of the present invention has the following effects. (1) The first embodiment of the present invention includes an angular velocity sensor 7 and an acceleration sensor 8 for detecting shakes having different properties. For this reason, angle blur can be detected and corrected, and the amount of blur can be calculated with high precision even in a shooting situation at a close distance where the shooting image magnification is high so that the effects of parallel blur cannot be ignored. As a result, it is possible to improve the shake correction ability.

(2) In the first embodiment of the present invention, a photographed image magnification β is obtained based on the focal length of a lens and a subject distance, and it is determined whether or not the photographed image magnification β is larger than a threshold value B. Thus, the reference ratio of the output signals of the angular velocity sensor 7 and the acceleration sensor 8 can be changed. For this purpose, the output signals of the angular velocity sensor 7 and the acceleration sensor 8 are switched according to shooting conditions such as the focal length and the subject distance,
It is possible to accurately calculate the blur amount and correct the blur with high accuracy.

(3) The first embodiment of the present invention is based on only the angular velocity signal ω when the photographed image magnification β is low, the subject distance is long, and most of the causes of the blur are angular blur. Te, can be accurately calculated shake amount D _i. As a result, motion compensation CPU6 in order to stop the processing of the parallel shake amount D _para by the acceleration signal alpha, reduce it is possible to calculation error is prevented from accumulating, the load of the power consumption and amount of calculation can do. Further, since the arithmetic processing is simplified, the speed of the arithmetic processing can be increased, and a low-cost microcomputer can be used, so that an inexpensive shake correction camera can be manufactured.

(Other Embodiments) The present invention is not limited to the above-described embodiments, and various modifications or changes can be made as described below. Within range. (1) Although the embodiment of the present invention has been described by taking an example of a lens-integrated image stabilizing camera, the present invention is also applicable to a camera body, an interchangeable lens or an intermediate adapter detachable from the camera body. Can be. Further, the present invention is not limited to an interchangeable lens having a fixed focal length, but can also be applied to a zoom lens having a continuously variable focal length. Further, the present invention is not limited to a still camera, but can be applied to an imaging device such as a digital still camera or a video camera, or an optical device such as a binocular or a telescope.

(2) In the embodiment of the present invention, the angular velocity sensor 7 has been described as an example. However, the present invention can be applied to an angular acceleration sensor that detects angular acceleration. Further, a rolling detection sensor for detecting shake around the optical axis O may be added, or a Z-axis detection sensor for detecting acceleration in the optical axis O direction may be added. Further, each of the angular velocity sensor 7 and the acceleration sensor 8 may be configured by a plurality of sensor groups, or may be configured by a single component. For example, the acceleration sensor 8 may be a sensor that detects two axes or three axes simultaneously.

(3) In the embodiment of the present invention, the threshold B
Has been described as an example, but is not limited to this value. For example, if you want to correct blur with high accuracy, set the threshold value B to a small value,
When it is desired to reduce the calculation load, the threshold value B can be set to a large value. In addition, since a high-performance interchangeable lens is equipped with a high-precision microcomputer, even if the calculation amount increases, the threshold value B can be set to a small value, and the blur amount can be calculated accurately. On the other hand, inexpensive interchangeable lenses
By setting the threshold value B to a large value, it is possible to reduce a calculation error caused by using the acceleration sensor 9.

[0071] (4) embodiments of the present invention has been compared with the imaging magnification β and the threshold B, and after the operation of the angular shake amount Dθ and parallel shake amount D _para, the ratio of the respective vibration amplitude calculates and may calculate the shake amount D _i without considering blur the smaller. In this case, the influence of the other axis sensitivity (crosstalk) of the sensor can be reduced, and the influence of the output drift and noise of the sensor can be removed.
Further, although the blur correction CPU 6 compares the photographed image magnification β with the threshold value B, it may compare whether the subject distance 1 is smaller than a certain threshold value.

(5) In the embodiment of the present invention, when the photographed image magnification β is low, the processing of calculating the parallel blur amount _Dpara is stopped, but the power supply to the acceleration sensor 8 and its amplifier circuit is stopped. Thus, power consumption can be further reduced. Further, although the calculation processing of the parallel shake amount _Dpara is stopped, the supply of power to the acceleration sensor 8 may be continued to detect a fluctuation in the output of the sensor. In this case, since the acceleration sensor 8 does not frequently repeat the ON operation and the OFF operation, it is possible to prevent drift immediately after turning on the power and use the acceleration sensor 8 in a stable state.

(6) In the embodiment of the present invention, the switching unit 20
Although the threshold value B is set to an arbitrary value, a mode in which the acceleration sensor 9 is not used may be provided.

[0074]

As described above in detail, according to the present invention, based on the output signal of the parallel blur detection unit and / or the angle blur detection unit in accordance with the subject distance or the photographed image magnification,
Since the calculation unit calculates the amount of blur, the amount of blur can be calculated with high accuracy according to the shooting situation, and the blur can be accurately corrected.

[Brief description of the drawings]

FIG. 1 is a block diagram of a shake correction camera according to a first embodiment of the present invention.

FIG. 2 is a graph showing a ratio of a blur factor to a subject distance.

FIG. 3 is a graph showing a ratio of a blurring factor to a photographed image magnification.

FIG. 4 is a block diagram illustrating a calculation process in a case where a shake amount is calculated in consideration of only an angle shake in the shake correction camera according to the first embodiment of the present invention.

FIG. 5 is a block diagram illustrating a calculation process when calculating a shake amount in consideration of an angle shake and a parallel shake in the shake correction camera according to the first embodiment of the present invention.

FIG. 6 is a flowchart illustrating a process of calculating a shake amount in the shake correction camera according to the first embodiment of the present invention.

FIG. 7 is a diagram for explaining a blur amount when an angle change occurs with respect to an optical axis.

FIG. 8 is a diagram for explaining a blur amount when a parallel change occurs in the optical axis in addition to an angle change.

FIG. 9 is a diagram for explaining a method of calculating a parallel movement amount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blur correction optical system 2 Drive unit 4 Main CPU 6 Blur correction CPU 7 Angular velocity sensor 8 Acceleration sensor 20 Switching unit O Optical axis

Claims (7)

[Claims] 1. An interchangeable lens that can be mounted on a camera body, comprising: a parallel shake detection unit that detects a shake that translates an optical axis of a photographing optical system in parallel; And a calculation unit for calculating a shake amount, wherein the calculation unit is configured to calculate a shake amount based on an output signal of the parallel shake detection unit and / or the angle shake detection unit in accordance with a subject distance or a captured image magnification. An interchangeable lens characterized in that: 2. The interchangeable lens according to claim 1, wherein the calculating unit is configured to detect the angular blur when the subject distance is longer than a predetermined distance or when the photographed image magnification is smaller than the predetermined magnification. Based only on the output signal of
An interchangeable lens characterized by calculating a blur amount. 3. The interchangeable lens according to claim 1, wherein the calculation unit is configured to determine when an object distance is shorter than a predetermined distance.
Alternatively, when the photographed image magnification is larger than a predetermined magnification, a shake amount is calculated based on output signals of the parallel shake detection unit and the angle shake detection unit. 4. One of claims 1 to 3
In the interchangeable lens according to the item, the calculation unit, when the subject distance is longer than a predetermined distance,
Alternatively, when the photographed image magnification is smaller than a predetermined magnification, the calculation based on the output signal of the parallel blur detection unit is stopped. 5. One of claims 2 to 4
The interchangeable lens according to any one of the preceding claims, further comprising: a variable setting unit that variably sets the predetermined distance or the predetermined magnification to a predetermined value. 6. Any one of claims 1 to 5
The interchangeable lens according to claim, further comprising: a blur correction optical system that corrects blur, a drive unit that drives the blur correction optical system, and a control unit that drives and controls the drive unit according to the blur amount. The interchangeable lens, wherein the parallel shake detection unit is an acceleration detector that detects acceleration, and the angle shake detection unit is an angular velocity detector that detects an angular velocity. 7. A blurring detector that detects blurring that moves the optical axis of the photographing optical system in parallel, an angle blurring detector that detects blurring that tilts the optical axis, a blurring correction optical system that corrects blurring, A driving unit that drives the shake correction optical system; a calculation unit that calculates a shake amount; and a control unit that drives and controls the drive unit in accordance with the shake amount. A shake correction camera, wherein a shake amount is calculated based on an output signal of the parallel shake detection unit and / or the angle shake detection unit according to an image magnification.