JP2007163687A - Image blur correcting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image blur correcting device capable of performing an image blur correction matching a use state, a user's demand etc., by varying vibration-proof characteristics with continuous characteristics. <P>SOLUTION: A CPU 40 of the image blur correcting device computes a displacement quantity of a vibration-proof lens 28 for preventing an image blur based upon an angular velocity signal from an angular velocity sensor 10 and outputs a control signal for moving the vibration-proof lens 28 to the position to a motor driving circuit 24. Further, the CPU 40 sets and varies an operation parameter used to calculate the displacement quantity of the vibration-proof lens 28 based upon a volume value of a volume 36. The volume value is a continuous value and the operation parameter is varied to a continuous value. Consequently, vibration-proof characteristics can be varied with continuous characteristics and set to vibration-proof characteristics matching the use state, user's demand, etc. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image shake correction apparatus, and more particularly to an image shake correction apparatus that corrects (prevents) image shake of a camera due to vibration.

  As an image shake correction device for a TV camera, an anti-vibration lens is placed in the photographic optical system so that it can move in a plane perpendicular to the optical axis. An image stabilization lens is driven by an actuator so as to cancel the image to correct image blur (see, for example, Patent Documents 1 and 2). In such an image shake correction apparatus, for example, an angular velocity sensor is used as a shake detection sensor for detecting vibration applied to the camera, and the image shake is canceled by integrating the angular velocity signal obtained from the angular velocity sensor. The position of the anti-vibration lens (the amount of displacement from the reference position) is obtained, and the anti-vibration lens is driven accordingly. In addition to the method of using an anti-vibration lens that moves in a plane orthogonal to the optical axis, a method of correcting image blur is known. In any of the image blur correction methods, an image displacement means for optically or electronically displacing an image formation position of an image formed by the optical system in the horizontal or vertical direction within the image formation plane is provided. Image blur correction is performed by controlling the amount of image displacement by the image displacement means so as to cancel the image blur.

Further, Patent Document 3 proposes an image blur correction apparatus that can change a table indicating response characteristics of image blur correction with respect to vibration and can perform image blur correction in accordance with hand shake characteristics for each user. Yes.
JP 2001-142103 A JP 2003-107554 A JP 2002-16837 A

  However, in the image blur correction apparatus proposed in Patent Document 3, the response characteristic (anti-vibration characteristic) is changed by changing the table, so that the number of anti-vibration characteristics is limited (several types). It can only be changed. There are various situations in which image blur correction is used, and what kind of anti-shake characteristics are desired varies depending on the user. There is a problem that it cannot respond to the situation and various requests of users.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an image blur correction apparatus capable of performing image blur correction adapted to usage conditions, user requests, and the like.

  In order to achieve the above object, an image shake correction apparatus according to claim 1 includes a shake detection unit that outputs a shake signal corresponding to vibration applied to an optical system that forms an image, and an image that displaces the image. A displacement means, a photographing composition change operation determining means for determining whether or not a photographing composition changing operation such as panning or tilting is performed based on a shake signal output from the shake detecting means, and the shake detecting means; Based on the output shake signal, the image displacement correction processing for displacing the image by the image displacement means so as to cancel the image shake caused by the vibration applied to the optical system, and the photographing composition change operation determination means When it is determined that the photographing composition change operation is being performed, the control means for stopping or suppressing the image shake correction process and the shake output by the shake detection means The response characteristics when an image is input and the displacement amount of the image obtained by the image displacement means determined by the control means is output can be changed to any of the continuously changing characteristics. Response characteristic setting means for setting the response characteristic, and an instruction means for instructing to set the response characteristic set by the response characteristic setting means to a desired characteristic among the continuously changing characteristics. It is a feature.

  According to the present invention, since the response characteristic (anti-vibration characteristic) with respect to the vibration applied to the optical system can be changed with a continuous characteristic in the calculation of the image displacement amount by the image displacement unit, the anti-vibration characteristic is small. Adjustment is possible, and image blur correction can be performed with image stabilization characteristics that appropriately correspond to usage conditions, user requests, and the like.

  According to a second aspect of the present invention, there is provided the image shake correction apparatus according to the first aspect, wherein the response characteristic setting unit performs an operation when the control unit obtains a displacement amount of the image based on the shake signal. 1 or a plurality of calculation parameters used for processing, and 1 used for calculation processing executed when the shooting composition change operation determination unit determines whether or not the shooting composition change operation is performed based on the shake signal. Alternatively, at least one of the plurality of calculation parameters is set to be changeable to an arbitrary value within a predetermined range, and is set to a value based on an instruction from the instruction means. The present invention shows that the calculation parameter in the control means or the photographing composition change operation determination means is changed in order to change the response characteristic. The change of the calculation parameter in the control means mainly affects the effectiveness of the image shake correction (anti-shake), and the change of the calculation parameter in the photographing composition change operation determination means mainly affects the occurrence of the shakeback during panning or tilting. Affect.

  According to a third aspect of the present invention, in the image blur correction apparatus according to the second aspect of the invention, the photographing composition change operation determination unit determines whether or not the photographing composition change operation is performed based on the shake signal. One or a plurality of calculation parameters used for the calculation process to be executed at the time includes a predetermined threshold value for determining whether or not the photographing composition change operation is performed. The present invention shows a specific example of calculation parameters.

  According to a fourth aspect of the present invention, in the image blur correction apparatus according to the first, second, or third aspect of the invention, the instruction unit includes one instruction value for determining a value of a calculation parameter in the control unit, A desired response characteristic is instructed by one instruction value for determining a value of a calculation parameter in the photographing composition change operation determining means. The present invention shows a mode in which, for example, the calculation parameter of the control means and the calculation parameter of the photographing composition change operation determination means can be changed separately by two volumes. According to this, it is possible to individually adjust calculation parameters that mainly affect the degree of image blur correction (anti-vibration) and calculation parameters that mainly affect the degree of shakeback during panning or tilting. it can.

  The image shake correction apparatus according to claim 5, wherein a shake detection unit that outputs a shake signal corresponding to vibration applied to an optical system that forms an image, an image displacement unit that displaces the image, and the shake detection unit Control means for executing image blur correction processing for displacing an image by the image displacement means so as to cancel image blur caused by vibration applied to the optical system based on a shake signal output by the image sensor, and the shake detection means The response characteristic when the image displacement amount obtained by the image displacement means obtained by the control means with respect to the input is output as an output of the shake signal output by the control means. A response characteristic setting unit that is set to be changeable to a specific characteristic, and an instruction to set a response characteristic set by the response characteristic setting unit to a desired characteristic among the continuously changing characteristics Is characterized by comprising: a stage, a.

  According to the present invention, since the response characteristic (anti-vibration characteristic) with respect to the vibration applied to the optical system can be changed with a continuous characteristic in the calculation of the image displacement amount by the image displacement unit, the anti-vibration characteristic is small. Adjustment is possible, and image blur correction can be performed with image stabilization characteristics that appropriately correspond to usage conditions, user requests, and the like.

  An image blur correction apparatus according to a sixth aspect of the present invention is the image blur correction apparatus according to the fifth aspect, wherein the response characteristic setting unit performs an operation when the control unit calculates the displacement amount of the image based on the blur signal. Among the one or more calculation parameters used for processing, at least one calculation parameter is set to be changeable to an arbitrary value within a predetermined range, and is set to a value based on an instruction from the instruction means. Yes. The present invention shows changing the operation parameter in the control means in order to change the response characteristic.

  According to a seventh aspect of the present invention, in the image blur correction device according to the second, third, or sixth aspect of the present invention, an arithmetic process executed when the control means obtains the displacement amount of the image based on the blur signal. The one or more calculation parameters used in the above include at least one of an integration filter coefficient in the integration process and a gain value in the amplification process. The present invention shows a specific example of calculation parameters.

  The invention according to claim 8 is the invention according to any one of claims 1 to 3, and 5 to 7, wherein the instruction means indicates a desired response characteristic by one instruction value. It is said. The present invention shows a mode in which the response characteristic is changed by an instruction value set by one volume, for example.

  According to the image blur correction apparatus according to the present invention, it is possible to perform image blur correction adapted to the use situation, the user's request, and the like.

  The best mode for carrying out the image blur correction apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing the configuration of an image blur correction apparatus according to the present invention. The image blur correction device is mounted on, for example, a lens device (photographing lens) for a television camera, a movie camera, or a still camera. The image stabilization lens 28 shown in FIG. In an optical system such as a camera, it is arranged so as to be movable up and down (vertical direction) and left and right (horizontal direction) in a plane perpendicular to the optical axis. The anti-vibration lens 28 is driven up and down or left and right by a motor 26. When vibration occurs in the camera (optical system), a position where image stabilization is corrected by the motor 26. It moves to (position where image shake due to vibration is canceled). Since the vibration-proof lens 28 is driven by performing the same processing on the vibration generated in each direction in both the vertical direction and the horizontal direction, the image blur correction in the horizontal direction is shown in FIG. Only the configuration to be performed is shown, and the description is omitted assuming that the configuration is the same in the vertical direction.

  An angular velocity sensor 10 shown in the figure is a shake detection sensor that detects vibration applied to an optical system, and is, for example, a gyro sensor. The angular velocity sensor 10 is installed on the upper surface of the lens barrel, for example, and outputs an electric signal having a voltage corresponding to the angular velocity of vibration generated in the left-right direction of the lens barrel as an angular velocity signal. Note that an acceleration sensor, a displacement sensor, or the like may be used as the shake detection sensor in addition to the angular velocity sensor, and the present invention can be applied even in such a case.

  The angular velocity signal output from the angular velocity sensor 10 is input to a high-pass filter (HPF) 12, and the signal component on the lower frequency side than the predetermined cutoff frequency is blocked by the HPF 12, and the signal on the higher frequency side than the cutoff frequency. Components are extracted and pass through the HPF 12. As a result, a signal component in a low frequency region such as a null voltage (DC offset voltage) is removed from the output of the angular velocity sensor 10, and when the null voltage fluctuates due to temperature drift or the like, the signal component is removed.

  The angular velocity signal that has passed through the HPF 12 is subsequently amplified by the amplifier circuit 14, converted from an analog signal to a digital signal by the A / D converter 16, and input to the CPU 40. The angular velocity signal input from the A / D converter 16 to the CPU 40 is referred to as a first angular velocity signal.

  The CPU 40 has various arithmetic processing functions. When the arithmetic processing functions of the CPU 40 are represented by functional blocks according to processing contents, as shown in the block of the CPU 40 in the figure, the integration processing unit 18, the amplification processing unit 20, the pan / tilt A determination unit 34 and the like are provided.

  The first angular velocity signal input from the A / D converter 16 to the CPU 40 is input to the integration processing unit 18 and is integrated by the integration processing unit 18 to be converted into an angle signal. Then, the amplification processing unit 20 amplifies the angle signal with a predetermined gain value. Thereby, the position (displacement from the reference position (center position)) of the image stabilizing lens 28 for displacing the image in the direction and size to cancel the image shake caused by the vibration of the optical system is obtained. The integration processing unit 18 performs processing of an integration filter (low-pass filter) that performs digital integration.

  The displacement amount value of the image stabilization lens 28 obtained by the amplification processing unit 20 is output from the CPU 40 to the D / A conversion unit 22 as a control signal having a value indicating the movement target position of the image stabilization lens 28. Then, after being converted from a digital signal to an analog signal by the D / A converter 22, it is input to the motor drive circuit 24.

  The motor drive circuit 24 drives the motor 26 based on the value of the control signal input from the D / A converter 22 and moves the image stabilization lens 28 in the left-right direction. As a result, the anti-vibration lens 28 moves to a position corresponding to the value of the control signal output from the CPU 40, and image blur due to vibration applied to the optical system is corrected.

  On the other hand, an angular velocity signal for pan determination is branched from an angular velocity signal output from the angular velocity sensor 10 and before being input to the HPF 12 and input to the amplifier circuit 30. The angular velocity signal input to the amplifier circuit 30 is amplified by the amplifier circuit 30 and then converted from an analog signal to a digital signal by the A / D converter 32 and input to the CPU 40. The angular velocity signal input from the A / D converter 32 to the CPU 40 is referred to as a second angular velocity signal.

  The second angular velocity signal input from the A / D converter 32 to the CPU 40 is input to the pan / tilt determination unit 34, and the pan / tilt determination unit 34 performs pan determination based on the second angular velocity signal. In this description, only the left / right control of the image stabilizing lens 28 will be described, so that the pan / tilt determination unit 34 performs only pan determination processing. Tilt determination processing is performed from the angular velocity signal.

  The pan / tilt determination unit 34 samples the second angular velocity signal from the A / D conversion unit 32 at predetermined time intervals, and executes a pan determination process for determining whether the camera (optical system) is panned. For example, the pan determination process in the present embodiment is performed as follows.

  When the voltage of the second angular velocity signal when the optical system is in a non-vibrating state is set to a reference value (for example, 0) of the second angular velocity signal, the second angular velocity signal changes to the positive and negative sides around the reference value. Since the pan determination process is performed by the same process when the second angular velocity signal changes to the positive side and when it changes to the negative side, the second angular velocity signal changes to the positive side with respect to the reference value. Only the case where this is done will be described.

First, the pan / tilt determination unit 34 sets a predetermined threshold value (pan determination threshold) v _s and pan determination time t _s for the second angular velocity signal. Then, the value v of the second angular velocity signal sampled at predetermined time intervals, and determines whether the pan determination threshold v _s or more. If it is less than the pan judgment threshold value v _s, it is determined that panning is not performed. In contrast, the value v of the second angular velocity signal, if it becomes more pan determination threshold v _s is made from that point to the value v of the second angular velocity signal bread determination threshold v _s or more by measuring the elapsed time between that, the elapsed time, determines whether or not a pan determination time t _s or more. Determining if not a bread decision time t _s or more does not determine that the panning is being performed, when a pan determination time t _s or more, and panning at that time is being performed To do.

FIG. 2 illustrates a graph of the second angular velocity signal detected during the panning operation. In FIG. 2, the value v of the second angular velocity signal is equal to or higher than the pan determination threshold value v _{s at} the point P ₁ . is determined, the time elapsed from the point P ₁ at point P ₂ is determined as the pan determination time t _s or more, it is determined that panning is being performed.

  When the pan / tilt determination unit 34 determines that panning is being performed, the pan / tilt determination unit 34 causes the integration processing unit 18 to execute processing during panning operation (image blur correction stop processing for stopping image blur correction). A process of stopping the image stabilizing lens 28 at the center position of the movable range (a position where the optical axis of the image stabilizing lens 28 coincides with the optical axis of the entire photographing lens) is executed. For example, the value of the first angular velocity signal input to the integration processing unit 18 is invalidated, and the integration processing unit 18 is caused to execute integration processing assuming that a value (for example, 0) in a no-vibration state is forcibly input. Thereby, the anti-vibration lens 28 moves to the center position and stops. In FIG. 2, the locus indicated by the broken line represents the movement of the image stabilization lens 28. When the pan / tilt determination unit 34 determines that panning is being performed, the image blur correction operation is stopped and the center position is reached. Move to.

  If it is determined that panning is being performed, the image blur correction operation is not completely stopped by the image blur correction stop process, but the amount of displacement of the image stabilizing lens 28 is reduced more than usual. It is also possible to change to a process that reduces (suppresses) the effectiveness of image blur correction. The pan / tilt determination unit 34 also detects the end of panning after determining that panning is being performed. For example, the magnitude of the amount of change from the reference value of the acquired second angular velocity signal. Is determined not to exceed a predetermined threshold for a certain period of time, it is determined that panning has ended. At this time, the value of the first angular velocity signal input to the integration processing unit 18 is validated, normal integration processing is executed, and image blur correction is resumed.

  In FIG. 1, the image shake correction apparatus is provided with a volume 36 that outputs a value (voltage) corresponding to the rotational position of the knob. The output value (volume value) of the volume 36 is read by the CPU 40. It has become. It should be noted that the volume 36 can be installed at a desired location such as a lens apparatus housing or a lens apparatus controller in which the present image blur correction apparatus is incorporated. In addition, when the image shake correction apparatus is an adapter type apparatus that is externally attached to the lens apparatus, the image shake correction apparatus can be provided in a housing or the like of the image shake correction apparatus.

  The volume value of the volume 36 (rotary position of the knob) can be adjusted by the user when changing the image stabilization characteristics. The knob of the volume 36 is rotated, and a continuous value is obtained according to the rotational position. By changing the volume value of the output volume 36, the image stabilization characteristic can be continuously changed by the characteristic.

  The CPU 40 sets calculation parameter values used for various calculation processes based on the volume value read from the volume 36, and changes the calculation parameter value according to the volume value when the volume value is changed. . As a result, the vibration isolation characteristics are changed.

  That is, in the functional block of FIG. 1 represented by the contents of the arithmetic processing in the CPU 40, the volume value from the volume 36 is given to each of the integration processing unit 18, the amplification processing unit 20, and the pan / tilt determination unit 34, and integration processing is performed. The values of calculation parameters used in the calculation processing of the unit 18, the amplification processing unit 20, and the pan / tilt determination unit 34 are changed to continuous values corresponding to the volume values.

  The change of the calculation parameter in each processing unit will be described. The integration processing unit 18 uses an integration filter used when performing an integration filter (low-pass filter) calculation process (integration process) according to the volume value from the volume 36. The coefficient is changed, and the cutoff frequency is mainly changed accordingly.

  For example, the transfer function H (z) of the integral filter expressed by z-transform is

Is represented by At this time, by changing the value of the integral filter coefficient k to a value corresponding to the volume value, the cutoff frequency of the integral filter is changed.

Here, if the volume value of the volume 36 is changed so that it can be set to a continuous value in the range of a to c (a <c), each volume value in the range of the volume values a to c (a <c) is assumed. is changed to integral filter coefficient corresponding to the value is continuous value in the range of _{k a ~k c (k a>} k c). Volume value is set a, b, c (a < b <c) integration when it is set in the filter coefficient k is _{k a, k b, k c} (k a> k b> a k _c) Examples Assuming that the frequency characteristics of the term (1-k) / (1-kz ⁻¹ ) in the above equation (1) are as shown in FIG. According to this, the cutoff frequency of the integration filter is changed to f _ca , f _cb , and f _cc (f _ca <f _cb <f _cc ) with respect to the volume values a, b, and c. The frequency characteristic of the transfer function H (z) in the above equation (1) obtained by multiplying the term (1-k) / (1-kz ⁻¹ ) by such a frequency characteristic by A (k) is shown in FIG. It becomes like this. According to this, the cut-off frequency that is changed according to the integral filter coefficient substantially matches the change of the cut-off frequency in FIG. 3, but the gain is about 3 to 3 even if the integral filter coefficient changes according to the volume value. The characteristic is substantially unchanged in the frequency range of 10 Hz.

  As described above, the integration filter coefficient in the integration processing unit 18 is changed according to the volume value of the volume 36, so that the effect of image blur correction mainly on the low-frequency vibration among the vibrations applied to the camera is mainly improved. Be changed. The greater the volume value and the higher the cutoff frequency of the integral filter, the less effective the image blur correction is for low-frequency vibration (or large vibration), and the lower the volume value and the lower the integral filter cutoff frequency. The effectiveness of image blur correction for low frequency vibrations is increased.

  As a phenomenon specific to image blur correction, when the camera starts panning (or tilting), the pan / tilt determination unit 34 determines that panning (or tilting) is being performed. Due to the influence of the displacement of the anti-vibration lens 28 that has been operated, there is a so-called “shake back” phenomenon that the image moves even after panning is completed. By changing the integration filter coefficient in the integration processing unit 18, the degree of occurrence of this “shake back” is also changed. The larger the volume value and the higher the cutoff frequency of the integral filter, the smaller the gain of the integral filter with respect to the vibration of the low frequency, and the smaller the amount of occurrence of swing back. The lower the cut-off frequency, the greater the degree of backlash.

  In the amplification processing unit 20, the gain value used when the amplification process is performed is changed according to the volume value from the volume 36, and the magnitude (amplitude) of the displacement amount of the image stabilization lens 28 is changed.

For example, if the volume value of the volume 36 is changed so that it can be set to a continuous value in the range of a to c (a <c) as described above, the volume values a to c (a <c) Corresponding to each value in the range, the gain value α is changed to be a continuous value in the range of α _{a to} α _c (α _a > α _c ).

Here, when the volume value is set to a, b, c (a <b <c), the gain value α is set to α _a , α _b , α _c (α _a > α _b > α _c ). Shall. For example, when the magnitude of the gain value α _a when the volume value is a is the maximum value of 100%, the gain values α _b and α _c are reduced to 90% and 70%, respectively. At this time, the displacement amount of the anti-vibration lens 28 for canceling the image blur calculated by the amplification processing unit 20 with respect to the angle signal having a constant amplitude output from the integration processing unit 18 and input to the amplification processing unit 20 is a volume value. It changes as shown in FIG. 5 according to a, b, and c. According to this, the gain value α in the amplification processing in the amplification processing unit 20 is changed to α _a , α _b , α _c with respect to the volume values a, b, c, so that the volume value increases as the volume value increases. The displacement amount of the vibration lens 28 is reduced. That is, the amount of displacement of the image stabilizing lens 28 with respect to the same vibration becomes smaller as the volume value becomes larger.

  In this way, the gain value in the amplification processing unit 20 is changed according to the volume value of the volume 36, so that the effectiveness of image blur correction is mainly changed. That is, the greater the volume value and the smaller the gain value, the smaller the effect of image blur correction. The smaller the volume value and the greater the gain value, the greater the effect of image blur correction. Along with this, the occurrence of swing back is also changed. The larger the volume value and the smaller the gain value, the smaller the swing back occurs, and the smaller the volume value and the larger the gain value, the more the swing back occurs. The condition increases.

  Further, in the amplification processing unit 20 (or a processing unit (not shown) provided at the subsequent stage), the maximum displacement amount of the vibration-proof lens 28 is set to a predetermined displacement amount within a movable range regulated by the mechanical end of the vibration-proof lens 28. When the amount of displacement of the anti-vibration lens 28 obtained by limiting and applying the amplification processing to the input angle signal (the value of the control signal output to the D / A converter 22) exceeds the maximum amount of displacement The process of changing the displacement amount of the vibration-proof lens 28 to the value of the maximum displacement amount and limiting the movable range of the vibration-proof lens 28 to a range smaller than the range restricted by the mechanical end (correction range restriction process). May be done. Further, when the amount of displacement of the image stabilizing lens 28 exceeds the maximum amount of displacement, a process for returning the image stabilizing lens 28 to the center position may be performed.

  In this case, if the limited movable range of the vibration-proof lens 28 is referred to as a correction range, and the end of the correction range is referred to as a correction end, a displacement amount (maximum displacement amount) that is a correction end according to the volume value of the volume 36. It is also possible to change the correction range by changing the value of.

For example, as described above, the volume value of the volume 36 is changed so that it can be set to a continuous value in the range of a to c (a <c), and the range of the volume value a to c (a <c). maximum displacement amount to be corrected end in correspondence with each value shall be modified so as to be continuous values in the range of _{x a ~x c (x a>} x c) of. Then, what the volume value is set a, b, and c (a <b <c) the maximum displacement amount x _a if it is set _{to, x b, x c (x} a> x b> x c) Then, the maximum displacement amount of the image stabilizing lens 28 is changed as shown in FIG. 6 according to the volume value. According to this, the larger the volume value, the smaller the maximum displacement amount of the image stabilizing lens 28 and the smaller the correction range. When the displacement amount of the image stabilizing lens 28 calculated by the amplification processing unit 20 changes as shown by the curve in FIG. 8, the displacement amount exceeds the maximum displacement amount set according to the volume value. The vibration-proof lens 28 is held at the position of the maximum displacement amount.

  As described above, the correction range of the image stabilizing lens 28 is changed in accordance with the volume value of the volume 36, so that the effectiveness of image blur correction is mainly changed. That is, the greater the volume value and the smaller the correction range, the smaller the image blur correction effect. The smaller the volume value and the greater the correction range, the greater the image blur correction effect. Along with this, the amount of shakeback has also been changed. The condition increases.

In the pan / tilt determination unit 34, the pan determination threshold value v _s and the pan determination time t _s used for the pan determination process are changed according to the volume value from the volume 36. For example, it is assumed that the volume value of the volume 36 is changed so as to be set to a continuous value in the range of a to c (a <c) as described above, and the range of the volume value a to c (a <c). range of the values in the corresponding pan determination threshold v _s and pan determination time t _s is v, respectively _{sa ~v sc (v sa> v} sc) _{and, t sa ~t sc (t sa} > t sc) of It shall be changed so that it becomes a continuous value. When the volume value is set to a, b, c (a <b <c), the pan determination threshold value v _s and the pan determination time t _s are v _sa , v _sb , v _sc (v _sa > v _sb> and _{v sc), t sa, t} sb, t sc (t sa> t sb> When shall be set to t _sc), bread determination threshold v _s and pan determination time t _s is 7 As shown in FIG.

  According to this, by changing the pan determination threshold value and the pan determination time in the pan determination process in the pan / tilt determination unit 34 according to the volume value of the volume 36, mainly the occurrence of the swingback is achieved. Be changed. That is, as the volume value increases and the pan determination threshold value and the pan determination time decrease, it is easier to determine that panning has been performed, and the degree of occurrence of shakeback decreases. As the volume value decreases and the pan determination threshold value and the pan determination time increase, it is difficult to determine that panning has been performed, and the degree of occurrence of shakeback increases. Along with this, the effect of image blur correction is also changed. As the volume value increases, the effect of image blur correction decreases, and as the volume value decreases, the effect of image blur correction increases.

  By changing the volume value of the volume 36 as described above, the calculation parameters used for each calculation process in the integration processing unit 18, the amplification processing unit 20, and the pan / tilt determination unit 34 are changed. The vibration characteristics change, and the degree of image blur correction, the occurrence of shakeback, and the like are changed. In the above example, the larger the volume value as a whole, the smaller the effect of image shake correction and the degree of shakeback, and the smaller the volume value, the greater the effect of image shake correction and the amount of shakeback. In this way, each calculation parameter is changed.

  The correspondence relationship between the volume value and each calculation parameter may be opposite to that in the present embodiment, and the larger the volume value, the greater the effect of image blur correction and the degree of occurrence of shakeback. It may be.

  Next, the processing procedure for changing the calculation parameter in the CPU 40 will be described with reference to the flowchart of FIG. In the CPU 40, the process of the flowchart shown in FIG. 8 is repeatedly executed, and the CPU 40 first reads the first angular velocity signal and the second angular velocity signal output from the angular velocity sensor 10 (step S10). Subsequently, the volume value is read from the volume 36 (step S12). Then, it is determined whether or not there is a change with respect to the volume value at the previous reading (step S14). If YES is determined, based on the volume value read in step S12, the calculation parameter for integration processing (integration filter coefficient in the integration processing unit 18) and the calculation parameter for amplification processing (in the amplification processing unit 20) as described above. ) And pan calculation processing parameters (pan determination threshold and pan determination time in the pan / tilt determination section 34) are set (step S16). In the above description, when performing the correction range limiting process for limiting the movable range of the image stabilizing lens 28 in the amplification processing unit 20 or the like, the maximum displacement amount of the image stabilizing lens 28 that determines the correction range can also be changed by the volume value. In this case, the maximum displacement amount is also set based on the volume value. Further, the process of step S16 is always executed once because it is determined that the volume value has changed even if the user does not operate the volume 36 immediately after the start of the image blur correction process.

  After executing the process of step S16 or when determining NO in step S14, the CPU 40 subsequently executes a pan determination process based on the second angular velocity signal read in step S10 (step S18). The pan determination process is described as a process performed by the pan / tilt determination unit 34.

  Next, the CPU 40 determines whether or not the camera is panning by the pan determination process in step S18 (step S20). If NO is determined, in order to execute image blur correction processing, integration processing is executed based on the first angular velocity signal read in step S10 (step S22), and then amplification processing is executed (step S24). ). Note that the integration process in step S22 has been described as a process performed by the integration processing unit 18, and the amplification process in step S24 has been described as a process performed by the amplification processing unit 20.

  When the displacement amount of the image stabilizing lens 28 for correcting the image blur is calculated by the processing in step S22 and step S24, a control signal instructing movement to the position corresponding to the displacement amount is output to the D / A converter 22. (Step S28). As a result, the image stabilizing lens 28 is moved to the position designated by the control signal, and image blur is corrected (prevented).

  On the other hand, if YES is determined in step S20, an image blur correction stop process for stopping image blur correction is executed (step S26). This process is a process of calculating a displacement amount of the image stabilizing lens 28 for returning the image stabilizing lens 28 to the center position and stopping it when the pan / tilt determining unit 34 determines that panning is performed.

  The CPU 40 outputs to the D / A converter 22 a control signal for instructing the movement of the image stabilizing lens 28 to the position corresponding to the displacement calculated by the image blur correction stop process (step S28). As a result, the vibration-proof lens 28 moves to the position designated by the control signal, and finally moves to the center position and stops.

  When the process of step S28 ends, the process from step S10 is repeatedly executed.

  Next, another embodiment of the image blur correction apparatus according to the present invention will be described. In the above-described embodiment, each calculation parameter in the CPU 40 is collectively changed by one volume 36. However, the calculation parameters are divided into a plurality of groups according to the characteristic contents that change due to the change of the calculation parameter, and are separately provided. The volume may be changed.

  FIG. 9 shows image blur when the image stabilization characteristic can be changed by two volumes, a volume 40 that mainly changes the effect of image blur correction and a volume 42 that mainly changes the degree of occurrence of shakeback. It is the block diagram which showed the structure of the correction | amendment apparatus. Note that the same reference numerals as those in FIG. 1 are attached to processing units having the same or similar functions as those in FIG.

  In the same figure, the two volumes 40 and 42 output continuous values (voltages) corresponding to the rotational positions of the respective knobs similarly to the volume 36 of FIG. Volume value) is read by the CPU 40. It should be noted that the volumes 40 and 42 can be installed in a desired location such as a lens device housing or a lens device controller in which the present image blur correction device is incorporated, as with the volume 36 of FIG. In addition, when the image shake correction apparatus is an adapter type apparatus that is externally attached to the lens apparatus, the image shake correction apparatus can be provided in a housing or the like of the image shake correction apparatus.

  The CPU 40 sets values of calculation parameters to be used for various calculation processes based on the respective volume values read from the volume 40 and the volume 42. When the volume value is changed, the CPU 40 sets the calculation parameter value according to the volume value. Change the value.

  In the present embodiment, the calculation parameter for integration processing (integration filter coefficient of the above equation (1) in the integration processing unit 18) is changed based on the volume value from the volume 40, and the calculation parameter for amplification processing (amplification processing). The gain value of the unit 20 is changed. For example, the relationship between the volume value of the volume 40 and the integral filter coefficient and gain value set and changed with respect to the volume value is the relationship between the volume value of volume 36 and the integral filter coefficient and gain value exemplified in the embodiment of FIG. It is the same.

  Therefore, as the volume value of the volume 40 increases, the integral filter coefficient in the integration process decreases and the cutoff frequency of the integration filter increases. The gain value in the amplification process is reduced. As a result, the greater the volume value of the volume 40, the smaller the effectiveness of image blur correction, and the smaller the occurrence of shakeback.

  Note that, when the correction range limiting process is performed in the amplification processing unit 20 or the like, the maximum displacement amount of the image stabilizing lens 28 that determines the correction range may also be set and changed based on the volume value of the volume 40. In this case, the maximum displacement amount may be set according to the volume value of the volume 40 in the same manner as the relationship between the volume value of the volume 36 and the maximum displacement amount set for the volume value in the above embodiment.

  On the other hand, the calculation parameters in the pan determination process, that is, the pan determination threshold value and the pan determination time in the pan / tilt determination unit 34 are set and changed based on the volume value of the volume 42. For example, the relationship between the volume value of the volume 42 and the pan determination threshold value and the pan determination time set and changed for the volume value is as follows. It is the same as the relationship with time.

  Therefore, as the volume value of the volume 42 increases, the pan determination threshold value and the pan determination time decrease, and the degree of occurrence of shakeback mainly decreases. Along with this, the effect of image blur is also reduced.

  FIG. 10 is a flowchart showing the processing procedure of the CPU 40 when setting and changing the operation parameters by the two volumes 40 and 42 as shown in FIG. The CPU 40 repeatedly executes the process of the flowchart shown in FIG. 10, and the CPU 40 first reads the first angular velocity signal and the second angular velocity signal output from the angular velocity sensor 10 (step S40). Subsequently, a volume value (referred to as a first volume value) is read from the volume 40, and a volume value (referred to as a second volume value) is read from the volume 42 (step S42).

  Next, the CPU 40 determines whether or not the first volume value read in step S42 has changed with respect to the first volume value that was read last time (step S44). If YES is determined, based on the first volume value read in step S42, the calculation parameter for integration processing (integral filter coefficient in the integration processing unit 18) and the calculation parameter for amplification processing (gain in the amplification processing unit 20) Value) is set (step S46). In addition, when performing the correction range restriction process for restricting the movable range of the image stabilization lens 28 in the amplification processing unit 20 or the like, the maximum displacement amount of the image stabilization lens 28 that determines the correction range can be changed by the volume value. In that case, the maximum displacement amount is also set based on the first volume value. Further, the process of step S46 is always executed once because it is determined that the volume value has changed even when the user does not operate the volume 40 immediately after the start of the image blur correction process.

  After executing the process of step S46 or when determining NO in step S44, the CPU 40 subsequently changes the second volume value read in step S42 with respect to the second volume value when read last time. It is determined whether or not there has been (step S48). If YES is determined, calculation parameters for the pan determination process (pan determination threshold and pan determination time in the pan / tilt determination unit 34) are set based on the second volume value read in step S42 (step S42). S50). It should be noted that the process of step S50 is always executed once because it is determined that the volume value has changed even if the user does not operate the volume 42 immediately after the start of the image blur correction process.

  Next, after executing the process of step S16 or when determining NO in step S48, the CPU 40 executes a pan determination process based on the second angular velocity signal read in step S40 (step S52). The pan determination process is described as a process performed by the pan / tilt determination unit 34 in the image shake correction apparatus of the embodiment of FIG.

  Next, the CPU 40 determines whether or not the camera is panning by the pan determination process in step S52 (step S54). If NO is determined, in order to execute image blur correction processing, integration processing is executed based on the first angular velocity signal read in step S40 (step S56), and then amplification processing is executed (step S58). ). The integration process in step S56 has been described as the process performed by the integration processing unit 18 in the image shake correction apparatus of the embodiment of FIG. 1, and the amplification process in step S58 is the same as that of the embodiment of FIG. This has been described as processing performed by the amplification processing unit 20 in the image shake correction apparatus.

  When the displacement amount of the image stabilizing lens 28 for correcting the image blur is calculated by the processing in step S56 and step S58, a control signal instructing movement to the position corresponding to the displacement amount is output to the D / A converter 22. (Step S62). As a result, the image stabilizing lens 28 is moved to the position designated by the control signal, and image blur is corrected (prevented).

  On the other hand, if YES is determined in step S54, an image blur correction stop process for stopping the image blur correction is executed (step S60). This processing is the image stabilization lens for returning the image stabilization lens 28 to the center position and stopping it when the pan / tilt determination unit 34 determines that panning is performed in the image stabilization apparatus of the embodiment of FIG. This is a process of calculating 28 displacement amounts.

  The CPU 40 outputs to the D / A converter 22 a control signal for instructing the movement of the image stabilizing lens 28 to the position corresponding to the displacement calculated by the image blur correction stop process (step S62). As a result, the vibration-proof lens 28 moves to the position designated by the control signal, and finally moves to the center position and stops.

  When the process of step S62 ends, the process from step S40 is repeatedly executed.

  As described above, in the embodiment shown in FIG. 1 and FIG. 9 and the like, the calculation parameters to be changed by the volume 36 or the volumes 40 and 42 are the integration filter coefficient in the integration processing unit 18 and the gain value in the amplification processing unit 20. (And the maximum amount of displacement when the correction range restriction process is performed), the pan determination threshold value and the pan determination time in the pan / tilt determination unit 34, but it affects the image stabilization characteristics in addition to these calculation parameters. Arbitrary parameters may be changed based on the volume or the like. For example, the cutoff frequency of the HPF 12 may be changed continuously. Further, it may be a case where any one of parameters affecting the image stabilization characteristic or a desired plurality of parameters can be changed.

  In the embodiment shown in FIG. 9, the calculation parameter changed by the volume 40 is one of the integral filter coefficient in the integration processing unit 18 and the gain value in the amplification processing unit 20, and is changed by the volume 42. The calculation parameter may be one of a pan determination threshold value and a pan determination time in the pan / tilt determination unit 34.

Here, a combination of calculation parameters to be changed by the volume 40 and the volume 42 and characteristics of the image stabilization characteristics corresponding to the values of the calculation parameters will be exemplified. For example, when the integration filter coefficient in the integration processing unit 18 is changed by the volume 40 and the pan determination threshold value in the pan / tilt determination unit 34 is changed by the volume 42, the integration filter coefficient in FIG. When the volume value a is set to the value k _a and the pan determination threshold value is set to the value v _sa at the volume value a in FIG. Can be corrected. However, the uncomfortable feeling during panning increases. This characteristic is suitable when the vibration is very large or when panning is hardly performed.

On the other hand, when the integral filter coefficient is set to the value k _c at the volume value c in FIG. 4 and the pan determination threshold is set to the value v _sc at the volume value c in FIG. 7, the uncomfortable feeling during panning is reduced. it can. It is difficult to correct image blur for low-frequency vibration or vibration with large amplitude. This characteristic is suitable when the camera is fixed to a tripod or the like.

For example, when the gain value in the amplification processing unit 20 is changed by the volume 40 and the pan determination time in the pan / tilt determination unit 34 is changed by the volume 42, the gain value is set to the volume value a in FIG. It is set to a value alpha _a time of setting the pan judgment time value t _sa when the volume value a in FIG. 7, can be corrected blur image for large vibration of not insufficiently corrected amplitude. However, there is a great sense of discomfort during panning. This characteristic is suitable when panning is not performed.

When the gain value is set to the value α _b at the time of the volume value b in FIG. 5 and the pan determination time is set to the value t _sb at the time of the volume value b in FIG. 7, there is little correction shortage and less uncomfortable feeling during panning. . It is difficult to correct image blur for vibrations having a large amplitude. This characteristic is suitable when the camera is used fixed to a tripod or the like.

When the gain value is set to the value α _c at the volume value c in FIG. 5 and the pan determination time is set to the value t _sc at the volume value c in FIG. 7, the correction is increased, but the uncomfortable feeling at the time of panning is increased. The smallest and natural image blur correction is performed.

  In the above embodiment, each calculation parameter is changed by a volume operated by an operation member such as a knob. However, any means for instructing a value of each calculation parameter may be used. For example, when the user inputs a numerical value, the value of each calculation parameter may be set to a value corresponding to the numerical value, or other means may be used.

  In the above-described embodiment, the image blur correction in the left-right direction has been described. However, the image blur correction in the vertical direction can be performed in the same manner, and the process related to tilting can be performed in the same manner as the process related to panning.

  Further, in the above-described embodiment, the image blur correction apparatus having a function of stopping or suppressing the image blur correction at the time of panning or tilting has been described, but the image blur correction apparatus having no such function is also described above. The present invention can be applied by application other than the part relating to the change of the calculation parameter of the pan / tilt determination unit 34.

  In the above embodiment, the image of the optical system is intentionally displaced by displacing the vibration-proof lens 28 so as to cancel the image blur due to the vibration. An image displacement means that intentionally displaces the image by displacing it is used to cancel the image shake due to vibration, or the image shake is not corrected by an optical image displacement means, but is captured by the image sensor of the camera. Even if the image cut-out caused by vibration is canceled by an electronic image displacing means that intentionally displaces an image by displacing a range that is cut out as a video signal for recording or reproduction from the range of the captured image The present invention can be applied.

FIG. 1 is a block diagram showing the configuration of an image blur correction apparatus according to the present invention. FIG. 2 is a diagram illustrating a graph of the second angular velocity signal detected during the panning operation. FIG. 3 is an explanatory diagram used to explain the change in the frequency characteristic of the integral filter due to the change in the integral filter coefficient. FIG. 4 is an explanatory diagram used to explain the change in the frequency characteristic of the transfer function of the integral filter due to the change of the integral filter coefficient. FIG. 5 is an explanatory diagram used to explain the characteristic change of the amplification process due to the change of the gain value. FIG. 6 is an explanatory diagram used to explain the change of the correction range of the image stabilizing lens. FIG. 7 is an explanatory diagram used to explain the change of the pan determination threshold value and the pan determination time in the pan determination process. FIG. 8 is a flowchart showing a processing procedure for changing the calculation parameter in the CPU. FIG. 9 is a block diagram showing the configuration of another embodiment of the image blur correction apparatus according to the present invention. FIG. 10 is a flowchart showing the processing procedure for changing the calculation parameter in the CPU of the image blur correction apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Angular velocity sensor, 12 ... High pass filter (HPF), 14, 30 ... Amplification circuit, 16, 32 ... A / D conversion part, 18 ... Integration processing part, 22 ... D / A conversion part, 24 ... Motor drive circuit, 26 ... Motor, 28 ... Anti-vibration lens, 34 ... Pan / tilt determination unit, 36 ... Volume, 40 ... CPU

Claims (8)

A shake detection means for outputting a shake signal corresponding to the vibration applied to the optical system for forming an image;
Image displacement means for displacing the image;
Photographing composition change operation determining means for determining whether or not a photographing composition changing operation such as panning or tilting is performed based on a shake signal output by the shake detecting means;
Based on the shake signal output by the shake detection means, the image displacement correction processing is performed to displace the image by the image displacement means so as to cancel the image shake caused by the vibration applied to the optical system, and the imaging Control means for stopping or suppressing the image blur correction process when it is determined by the composition change operation determination means that the photographing composition change operation is being performed;
A characteristic that continuously changes the response characteristic when the shake signal output by the shake detection means is input and the displacement amount of the image by the image displacement means obtained by the control means is output with respect to the input. Response characteristic setting means for setting to change any characteristic of
An instruction means for instructing to set a response characteristic set by the response characteristic setting means to a desired characteristic among the continuously changing characteristics;
An image blur correction apparatus comprising:   The response characteristic setting means includes one or more calculation parameters used for calculation processing executed when the control means obtains the displacement amount of the image based on the shake signal, and the photographing composition change operation determination means Of the one or more calculation parameters used for the calculation process executed when determining whether or not the photographing composition changing operation is performed based on the shake signal, at least one calculation parameter is set to an arbitrary value within a predetermined range. 2. The image blur correction apparatus according to claim 1, wherein the value is set to be changeable and is set to a value based on an instruction from the instruction means.   The one or more calculation parameters used for the arithmetic processing executed when the photographing composition changing operation determining means determines whether or not the photographing composition changing operation is performed based on the shake signal are the photographing composition changing operation. The image blur correction apparatus according to claim 2, further comprising a predetermined threshold value for determining whether or not it is being performed.   The instruction means indicates a desired response characteristic by one instruction value for determining the value of the calculation parameter in the control means and one instruction value for determining the value of the calculation parameter in the photographing composition change operation determination means. 4. The image blur correction device according to claim 1, 2, or 3. A shake detection means for outputting a shake signal corresponding to the vibration applied to the optical system for forming an image;
Image displacement means for displacing the image;
Control means for executing image shake correction processing for displacing an image by the image displacement means so as to cancel image shake caused by vibration applied to the optical system based on a shake signal output by the shake detection means;
A characteristic that continuously changes the response characteristic when the shake signal output by the shake detection means is input and the displacement amount of the image by the image displacement means obtained by the control means is output with respect to the input. Response characteristic setting means for setting to change any characteristic of
An instruction means for instructing to set a response characteristic set by the response characteristic setting means to a desired characteristic among the continuously changing characteristics;
An image blur correction apparatus comprising:   The response characteristic setting means has at least one calculation parameter out of a predetermined range among one or a plurality of calculation parameters used for calculation processing executed when the control means obtains the displacement amount of the image based on the shake signal. The image blur correction apparatus according to claim 5, wherein the image blur correction apparatus is set so as to be changeable to an arbitrary value among the values, and is set to a value based on an instruction from the instruction means.   One or a plurality of calculation parameters used for calculation processing executed when obtaining the displacement amount of the image based on the shake signal in the control means are at least an integration filter coefficient in the integration processing and a gain value in the amplification processing. The image blur correction apparatus according to claim 2, wherein the image blur correction apparatus includes:   The image blur correction apparatus according to claim 1, wherein the instruction unit instructs a desired response characteristic by one instruction value.

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