JP3403528B2 - Vibration detector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration detecting device such as a camera shake detecting device for detecting a camera shake that causes deterioration of a photographed image, and a rotation detecting device for detecting a traveling direction of a vehicle used for a navigation system of a vehicle. It is about.

[0002]

2. Description of the Related Art Conventionally, there has been proposed an applied technique utilizing information on rotational vibration of a device for preventing deterioration of image quality due to vibration of a photographing device and for detecting / displaying a traveling position / direction of a vehicle. .

As a vibration detecting device for this purpose, a mechanical vibration detecting sensor such as an angular velocity sensor is used. Further, as a sensor for detecting vibration or angular velocity, a difference in output between a pair of mechanical-electrical energy conversion elements, which have normals of the same magnitude but opposite directions in the ultrasonic vibration direction of ultrasonic vibration, Alternatively, a signal proportional to the angular velocity around the axis orthogonal to the ultrasonic vibration direction is output from the phase shift,
A so-called vibration gyro-type angular velocity sensor is known.

[0004]

However, in such a device for detecting vibration of a photographing device or a traveling direction detecting device for a navigation device such as a car, the angular velocity detecting means or the like causes a drift due to a temperature change or the like, and the angular velocity is The 0 state is unstable. Also,
If there is vibration when the power is turned on even if there is no drift, the level of the state signal of vibration 0 tends to become unstable, and this instability easily leads to offset of the vibration signal.

Further, when the angular velocity is integrated to obtain a signal of the dimension of the angle, the drift and offset signal components are low-frequency components, so that the integration causes a significant error. Therefore, it is necessary to remove a low frequency component that is a drift component or an offset component of the vibration signal by using a high pass filter (HPF).

However, in the normal HPF, the removal effect can be changed only for the frequency of the signal. Therefore, the low-frequency vibration is removed in the same manner as the drift component, and as a result, an error occurs and it is difficult to accurately detect the vibration.

The present invention has been made in view of the above problems, and improves a high pass filter to effectively remove an offset component and a drift component included in a vibration signal.
An object of the present invention is to provide a vibration detection device that does not remove low-frequency components of a vibration signal more than necessary.

[0008]

That is, the present invention provides a vibration information detecting means for detecting vibration applied from the outside as vibration information, and a low frequency for removing a predetermined low frequency component mixed in the vibration information. comprising a component removing means, a change means for changing over the cutoff frequency of the low frequency component removing means time, and the low frequency component removing means
Is the angular velocity signal detected by the vibration information detecting means.
Change value of is multiplied by a predetermined coefficient to the previous calculation result and added
By removing the specified low frequency component,
The changing means is to change the coefficient to
It is characterized by changing the frequency . This invention
Detects vibration applied from the outside as vibration information
The vibration information detecting means and a predetermined information mixed in the vibration information.
Low frequency component removing means for removing low frequency components,
The low frequency component removing means is the vibration information detecting means.
To the change value of the angular velocity signal detected by
By adding the results of subtraction so that the result is smaller,
It is characterized in that a predetermined low frequency component is removed.

[0009]

In the vibration detecting device of the present invention, the vibration applied from the outside is detected by the vibration information detecting means as the vibration information. Then, the low frequency component removing means removes a predetermined low frequency component mixed in the vibration information. Further, the cutoff frequency of the low frequency component removing means is changed by the changing means with the passage of time. Here, the low-frequency component removing means detects the vibration information.
The change value of the angular velocity signal detected by
By multiplying the calculation result by a predetermined coefficient and adding,
The constant low frequency component is removed, and the changing means is
The cutoff frequency is changed by changing the number.
To be done. Further, in the vibration detecting device according to the present invention,
The more applied vibration is the vibration information detection
It is detected on the stage. And the place mixed in the vibration information
The constant low frequency component is removed by the low frequency component removing means.
In the low frequency component removing means, the vibration information detecting means is
Based on the change value of the angular velocity signal detected by
The subtracted result is added so that
As a result, a predetermined low frequency component is removed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the basic configuration of the vibration detecting device of the present invention. The vibration detection device shown in FIG. 1A includes a vibration detection unit 11 that detects vibration information and a non-linear HPF (high-pass filter) calculation unit 12 having a non-linear characteristic.

In such a structure, the vibration applied from the outside is detected by the vibration detecting section 11 as the vibration information. Then, the non-linear HPF calculation unit 12 having a non-linear removal characteristic that is not proportional to the magnitude of the detected vibration information outputs a vibration signal from which a predetermined low frequency component mixed in the vibration information is removed.

FIG. 1 (b) shows a first modification of the vibration detecting device of FIG. 1 (a). In the following description, the same constituent elements will be designated by the same reference numerals and the description thereof will be omitted.

This vibration detecting device is provided with a camera shake detecting section 13
And a non-linear HPF calculator 12 having non-linear characteristics. In this case, the vibration due to camera shake applied from the outside is detected by the camera shake detection unit 11 as vibration information. Then, the non-linear HPF calculator 12 having a non-linear removal characteristic that is not proportional to the magnitude of the detected vibration information outputs a camera shake signal from which a predetermined low frequency component mixed in the vibration information is removed.

The vibration detecting section 11 and the camera shake detecting section 13 can be constructed by using an angular velocity sensor 14 as shown in FIG. 1 (c). Further, the vibration detecting device may be configured as shown in FIG. That is, the vibration detection device includes a vibration detection unit 11 that detects vibration information, a nonlinear HPF calculation unit 12 having nonlinear characteristics, and an integration calculation unit 15 that integrates the output of the nonlinear HPF calculation unit 12.

With such a configuration, it is possible to convert the vibration signal into a higher-order vibration signal. By the way, the non-linear HPF calculation unit 12 is a calculation unit that performs a high-pass filter process that does not have a signal removal characteristic that is proportional to the magnitude of the signal processed in the calculation. Therefore, FIG. 2 (a)
As shown in FIG. 3, the calculation processing signal size determination unit 16 that determines the magnitude of the signal to be subjected to the HPF calculation processing,
The non-linear HPF arithmetic unit 12 can also be configured from the first arithmetic unit 17 and the second arithmetic unit 18 having the PF characteristic. According to this, it becomes possible to process with different HPF characteristics depending on the magnitude of the signal used for the calculation.

Further, as shown in FIG. 2B, the non-linear HPF calculation unit 12 includes a subtraction-type attenuation processing unit 19 for performing an attenuation process that is not proportional to the magnitude of the signal subjected to the HPF calculation process. It may be configured with the HPF calculation unit 20. With this configuration, the non-linear HPF calculator 12 can have a certain amount of attenuation that is not proportional to the magnitude of the signal processed in the calculation.

3 and 4 show an example of the structure of a camera having an anti-shake device to which the vibration detecting device according to the present invention is applied. FIG. 3 is an external perspective view of the camera of the embodiment, and FIG. It is a block diagram which shows schematic structure of a camera.

The front of the body of the camera 30 has a taking lens 31 and a finder 32 for observing an object. A release button 33 having a two-stage switch described later is provided on the upper surface of the body of the camera 30.

The camera controller 34 for controlling various operations of the camera 30 includes a taking lens for adjusting the focus of a subject image formed on the film 35 loaded in the body of the camera 30. A focus adjusting device 36 for moving 31; a photometric device 37 for measuring the brightness of the subject to obtain an appropriate exposure amount; and a first release switch (1stRs) for instructing the camera 30 to perform a shooting preparation operation.
w) 38 and a release button 33 including a second release switch (2ndRsw) 39 for instructing a shooting operation, an exposure device 40 for giving an appropriate exposure to the film 35, and a shooting device A film feeding device 41 for winding or rewinding the film 35, or holding the film 35, and a display unit 42 for appropriately displaying information processed by the camera 30, such as the operating state of the camera 30, the brightness of a subject, and the like. The camera shake prevention device 43 for detecting the camera shake of the camera 30 and realizing the shooting with the camera shake prevented is connected. Reference numeral 44 is a power supply unit for supplying electric power used in each unit in the camera 30.

The camera control section 34 includes a release button 33.
Of the focus adjustment device 36 and the photometric device 3
7, exposure device 40, film feeding device 41, display unit 42
Is controlled to operate at a predetermined timing in order to establish the function of the camera.

The camera control section 34 is a so-called 1-chip microcomputer (1chi) which is integrally formed with an I / O (input / output) section and a memory section.
pCPU). Then, the camera control unit 3
Reference numeral 4 realizes a predetermined camera operation in accordance with a program written in a read only memory (ROM).

Next, the operation of the camera 30 will be briefly described. FIG. 5 is a flow chart for explaining the rough operation of the camera control unit 34.

First, when the power is turned on, step S1
Then, execute the <Initial setting> routine. The operation here is to initialize the data in the memory (not shown), check the battery level, check the camera 30 for malfunctions, and if the camera collapses with the power off, return from the collapsed state, etc. , An initial setting operation of the lens position and the like are performed.

Next, in step S2, it is determined whether the first release switch 38 is operated by the photographer, and this operation is repeated until the operation is performed. When the operation of the first release switch 38 is detected in step S2, the process proceeds to step S3, and the camera shake prevention device 43 is instructed to start detecting the camera shake. In this case, an instruction to turn on the power may be included in the camera shake detection system. As a result, power can be saved without consuming power in the camera shake detection system until the first release switch 38 is operated, and the battery life of the camera 30 can be extended.

Next, in step S4, the focus adjustment device 36
Is used to check the distance to the subject and the focus state of the subject with an optical path length equivalent to that of the film 35, and drive so that the subject image position formed by the taking lens 31 is on the film 35. <focus adjustment > Run the routine. Then, in step S5, the <photometry> routine is executed in which the brightness of the subject is measured using the photometric device 37, and an appropriate amount of light that makes the amount of light applied to the film 35 appropriate is obtained.

In step S6, the movement information of the subject image due to the hand movement, that is, the state information of the hand movement is received from the hand movement prevention device 43. Then, in step S7, the display unit 42
Is used to display the focus state information, the subject brightness information, and the camera shake information for transmission to the photographer, and execute a <display> routine.

Next, in step S8, it is determined whether or not there is an exposure instruction from the photographer, and the second release switch 3
The operation is checked to make a determination. If there is a photographing instruction, the process proceeds to step S9, and if there is no instruction, the process proceeds to step S13 described later.

In step S9, the camera shake prevention device 43 is instructed to prevent camera shake during exposure or to start correction. Then, in step S10, the exposure apparatus 4
The object image is exposed on the film 35 using 0. This exposure device 40 controls the amount and time of light passing through the taking lens 31 using the diaphragm device and shutter device in the exposure device 40 in order to perform exposure with the appropriate amount of light determined in the <photometry> routine of step S5. To be done.

Then, in step S11, the camera shake prevention device 43 is instructed to end the camera shake prevention or correction. Then, in step S12, the film feeding device 41 is used to load the film 35 for the next shooting.
Advance pieces.

After finishing the processes relating to these exposures,
Return to step S8. On the other hand, if the shooting instruction cannot be detected in step S8, the process advances to step S13 to determine whether the photographer operates the first release switch 38. If an operation is being performed, the process returns to step S4 and the above operation is repeated.

If the operation of the first release switch 38 cannot be detected in step S13, there is no exposure preparation instruction from the photographer, so the process proceeds to step S14 to end the detection of camera shake with respect to the camera shake preventer 43. Give instructions. Then, the process returns to step S2 and the above operation is continued.

Now, the image stabilizing device 43 will be described. In general, camera shake occurs in the vertical direction, the horizontal direction, and the rotation direction with respect to the shooting screen. Usually, the shakes in the vertical and horizontal directions are the main components, so it is necessary to detect the shakes in the biaxial directions.

As described above, in reality, it is necessary to detect and correct blurring of two or three axes, but here, for simplification of the description, only one axis will be described. When performing detection on a plurality of axes, the axes may be controlled in parallel or each axis may be controlled in a time-division manner, and each processing portion is processed in a time-division manner. It is also possible to perform processing to some extent in parallel (locally time-sharing) with one control unit.

As shown in FIG. 6, the image stabilization apparatus 43 includes an image stabilization control section 46, an image stabilization processing section 47 for detecting an image stabilization and processing an image stabilization signal, and an image capturing operation based on the detected image stabilization information. It is configured with a hand shake prevention unit 48 that reduces hand shake. The camera shake prevention control unit 46 receives a signal from the camera control unit 34 and controls the operations of the camera shake detection processing unit 47 and the camera shake prevention unit 48.

The image stabilization control unit 46 is a dedicated microcomputer for image stabilization, and includes a register in the image stabilization control unit 46 and a random access memory (R).
I / O for exchanging data with AM)
It consists of ports and programs.

The camera shake prevention control section 46 also has a built-in A / D converter for digitizing the angular velocity signal. The camera shake prevention control unit 46 is configured by a so-called 1-chip CPU in which a program storage area, a variable storage area, a register, an I / O port unit, a control unit, and the like are integrated. Hereinafter, this CPU is referred to as a camera shake prevention CPU.

On the other hand, the camera shake detection processing unit 47 shown in FIG.
As shown in FIG. 3, the angular velocity sensor unit 50, the angular velocity amplification unit 51, the angular velocity signal high-pass filter (HPF) processing unit 52, the angular velocity prediction calculation unit 53, and the image moving speed calculation unit 54 are used. Detects the vibration rotation speed of the camera and outputs the moving speed of the subject image.

The approximate operation of the camera shake detection processing section 47 is as follows. That is, the angular velocity sensor unit 50
The output of is amplified by the angular velocity amplifier 51 into a predetermined signal. Then, the amplified signal is subjected to high-pass calculation processing by the angular velocity signal high-pass filter processing unit 52, and the angular velocity sensor unit 5
The drift component of the 0 output is removed. The processed signal is subjected to delay correction and conversion into a trajectory of change in the near future in the angular velocity prediction calculation unit 53, and then the image moving speed calculation unit 54 performs focal length information, subject distance information, and magnification information. Is used to convert the angular velocity signal into an image moving velocity signal.

The angular velocity predicting / calculating unit 53 is a means for predicting the near future transition of the camera shake signal. This predicting method is described in, for example, Japanese Patent Application Laid-Open No. HEI 5-1993.
Since it is described in detail in Japanese Patent No. 204012 and Japanese Patent Application No. 5-173144, the description thereof will be omitted here.

Here, the signal processing operation in the image moving speed calculator 54 will be described. When the camera shake rotation center is on the film surface, the geometrical ray tracing traces the shooting magnification between the rotation amount θ and the image movement amount d, and the focal length of the shooting lens 31 is f. f · (1 + β) · (1 + β) · sin (θ) Further, it can be seen that there is also a relationship of v = f · (1 + β) · (1 + β) · sin (ω) between the angular velocity ω and the image moving velocity v. .

Further, since the angle change due to camera shake is small, it can be approximately calculated as v = f · (1 + β) · (1 + β) · ω. More approximately, v = f · (1 + β) · ω or v = f · ω may be set.

As described above, it is known that the photographing magnification can be obtained from the subject distance and the focal length, and the method of obtaining the subject distance is being applied to the focus adjusting device. In addition, detection of the focal length of the taking lens is also known.

From these relationships, the movement of the subject image can be obtained from the angular velocity due to camera shake. The subject distance information and the focal length information of the photographing lens 31 necessary for this calculation are information sent from the camera control unit 34 which controls the main body of the camera 30.

When there is an error in sensitivity of the angular velocity sensor or the amplification part of the signal, v = α · f · (1 + β) · (1 + β) using the correction coefficient α to correct the sensitivity error. ) ・ Ω should be calculated. Also, in order to simplify the calculation,
In advance, once, as the angular velocity image velocity conversion coefficient γ, the calculation of γ = α · f · (1 + β) · (1 + β) is performed, and from the next time, by using this coefficient γ, v = γ · ω is calculated. The image moving speed is required.

By the way, the angular velocity sensor section 50 is a so-called vibrating gyro angular velocity sensor, and the piezoelectric material and the magnetostrictive material are arranged at the same size but at different angles with respect to the vibration direction on the vibrating piece vibrating ultrasonically. The rotational speed around the axis in the direction orthogonal to the vibration of the vibrating piece is output as voltage information from the phase shift or the amplitude difference of the output of the mechanical energy-electrical energy conversion element. The output of the angular velocity sensor unit 50 is amplified by the angular velocity amplification unit 51 to a predetermined size.

FIG. 8 is a block diagram showing an example of the configuration of the angular velocity amplification section 51. This angular velocity amplifier 51
Is a differential amplifier 61 and a differential amplifier reference voltage generator 62.
And a reference voltage control unit 63 and an output correction unit 64, and the output from the output correction unit 64 is output as a signal of the angular velocity amplification unit 51.

The output of the angular velocity sensor section 50 and the output of the differential amplifier reference voltage generating section 62 are input to the amplifying amplifier 61, and the difference between the two is amplified and output by the differential amplifying amplifier 61. The differential amplifier reference voltage generator 62
The output of is determined by the reference voltage control unit 63.

In the reference voltage control section 63, the differential amplification reference voltage is set so that the output of the differential amplifier 61 falls within a predetermined range. When the reference voltage is changed, the change in the output of the differential amplifier 61 when the reference voltage is changed is added to the output of the differential amplifier 61, so that the same reference as that before the change of the reference voltage is obtained. The output in the voltage state is calculated and obtained.

Further, in the output correction unit 64, every time the reference voltage is changed by the reference voltage control unit 63 using the differential amplifier reference voltage generation unit 62, the output change amount of the differential amplifier 61 due to the reference voltage change is changed. A correction signal is obtained by subtraction from the differential amplifier 61 and is output. If the reference voltage is not changed, the output of the differential amplifier 61 is directly output from the output correction unit 64.

For example, the amplification factor of the differential amplifier 61 is 100.
In the case of double, if the reference voltage is decreased by 10 mV, the output of the differential amplifier 61 is increased by 1V. At this point, the angular velocity signal output from the differential amplifier 61 also rises by 1V,
This is apparently only increased, and the value obtained by subtracting 1V from the output of the differential amplifier 61 is the correct value for the angular velocity signal. Such correction is performed by the output correction unit 64.

Returning to FIG. 7, the angular velocity signal high-pass filter processing section 52 performs a predetermined HPF processing calculation to remove the low frequency component contained in the angular velocity signal. The main reason for this is that the output of the vibration gyro-type angular velocity sensor includes an offset component due to temperature, and thus an absolute angular velocity signal is not output, and the HPF removes the offset and drift components due to this temperature.

In the HPF calculation, the change value of the detected angular velocity signal is Δx, the high-pass (HPF) calculation result is h, and
Assuming that the previous high-pass calculation result is h ′ and the weighting coefficient for the previous high-pass calculation result is kh, then h = Δx + kh · h ′ is obtained. Here, kh is a coefficient having a value of (0≤kh≤1).

The HPF characteristic can also be obtained by subtracting h ′ so as to make the value slightly smaller without using the coefficient kh. FIG. 9 shows the angular velocity amplification section 51.
3 is a block diagram showing a more specific configuration example of FIG.

The differential amplifier 61 in the angular velocity amplification section 51 is
Together with the differential amplifier reference voltage generator 62, the angular velocity detection IC 65 is a dedicated integrated circuit. The output of the differential amplifier 61 is the A / D in the camera shake prevention CPU 66.
It is digitized by the converter 67. Along with this, the reference voltage control unit 63 and the output correction unit 64 of the angular velocity amplification unit 51.
Is mainly composed of a program, a register, and a RAM in a camera shake prevention control unit (not shown).

The reference voltage control unit 63 further has a control signal generation unit which is an output port for instructing the differential amplifier reference voltage generation unit 62 which voltage to generate. The differential amplifier reference voltage generator 62 is composed of a D / A converter whose output voltage is instructed and controlled by the reference voltage controller 63 in the camera shake prevention CPU 66.

Further, the angular velocity signal high-pass filter processing unit 52, the angular velocity prediction calculation unit 53, and the image movement velocity calculation unit 54.
Also, the A / D converter 67, the reference voltage control unit 63,
It is realized using a program in the image stabilization CPU 66 together with the output correction unit 64.

Here, the operation of the reference voltage control unit 63 will be described with reference to FIG. The angular velocity output of the angular velocity sensor unit 50 is Vs, and the amplification factor of the differential amplifier 61 is β.
a and the reference voltage is Vk. Then, the output Va of the differential amplifier 61 is Va = βa (Vs-Vk) When the digitized angular velocity amplified signal of the output of the differential amplifier 61 is Vd, if Vd is higher than the predetermined value Vd _H ,
The reference voltage is increased by a predetermined value ΔVk. This allows
The output of the differential amplifier 61 changes to Va '.

[0058] Va '= βa · (Vs - (Vk + ΔVk)) = βa · (Vs -Vk) to -βa · ΔVk Conversely, if lower than Vd is the predetermined value Vd _L, the reference voltage is lowered by a predetermined value DerutaVk It As a result, the differential amplifier 6
The output of 1 is changed to Va ".

Va ″ = βa · (Vs− (Vk−ΔVk)) = βa · (Vs−Vk) + βa · ΔVk As described above, the reference voltage varies depending on the output of the differential amplifier 61. Output Va of the differential amplifier 61
, Vd will be varied between approximately predetermined values Vd _L and Vd _H. This is because the reference voltage is changed when the range between the predetermined values Vd _L and Vd _H is exceeded.

Therefore, the output of the differential amplifier 61 is not saturated while the reference voltage is being controlled, and the angular velocity signal of camera shake is not saturated and cannot be measured.
Next, the operation of the output correction unit 64 will be described.

When the reference voltage Vk is changed by the operation of the reference voltage controller 63, the digitized angular velocity signal Vd changes by (βaΔVk). If this variation is left as it is, the angular velocity signal remains the output of the differential amplifier 61, and the transition on the sawtooth is shown.

Since the change of the reference voltage is reflected in the next detection of the angular velocity, when the reference signal is increased by ΔVk, the output of the differential amplifier 61 is decreased by (βa · ΔVk). Therefore, (βa · ΔVk) should be added to the digitized signal of the angular velocity sensor next time. Conversely, when the reference signal drops by ΔVk, the output of the differential amplifier 61 becomes (βa
Since it increases by .DELTA.Vk), it is sufficient to subtract (.beta.a..DELTA.Vk) from the next digitized signal of the angular velocity sensor.

In the output correction unit 64, the reference voltage control unit 6 uses the previously digitized value for the digitized value.
3 when the reference voltage is fluctuated, the angular velocity signal Vd becomes (β
It is corrected by a.ΔVk).

The output of the output correction unit 64 is then processed by the angular velocity signal high pass filter processing unit 52.
The processing can be simplified by the operation of the output correction unit 64 according to this processing. That is, the output can be corrected without storing whether the reference voltage has changed at the previous detection.

As in the above equation, the high-pass filter operation calculates the change value of the detected digitized angular velocity signal by Δ.
Let Vd be the high-pass operation result, V _{hpf be} the previous high-pass operation result be V _hpf ′, and the weighting coefficient for the previous high-pass operation result be the HPF coefficient kh, and V _hph = ΔVd + kh · V _hpf ′. If the digitized angular velocity signal is Vd and the previous digitized angular velocity signal is Vd ', then _Vhpf = Vd-Vd' + _kh.Vhpf '.

When the reference voltage has increased by ΔVk between the previous time and this time, as described above, V _hpf = (Vd + (βa.ΔVk))-Vd '+ kh.
It is necessary to correct V _hpf ′ and the current angular velocity signal Vd.

By the way, this equation is: V _hpf = Vd + ((βaΔVk) -Vd ') + kh
V _hpf 'V _hpf = _Vd- (Vd'-(βa.ΔVk)) + kh.
Since it can be modified to V _hpf ′, the output fluctuation of the differential amplifier 61 due to the change of the reference voltage can be corrected by correcting the previous angular velocity signal by − (βa · ΔVk) when using the HPF. In this case, the process flow shown in FIG.

The correction value of the angular velocity signal may be stored as a constant with δ = βaΔVk, or may be data communicated from the camera control unit 34. In this case, V _hpf = Vd − ( _Vd′ −δ) + kh · V _hpf ′ or when the reference voltage is lowered by _ΔVk , V _hpf = Vd − (Vd ′ + δ) + kh · V _hpf ′ and the previous The digitized angular velocity signal Vd ′ is set to ± δ
It is possible to correct the angular velocity signal by changing the reference voltage of the differential amplifier 61 by only correcting and storing and using the corrected value.

By performing this high-pass filter processing, it is possible to perform encoding by adding the change amount of the angular velocity to the previous calculation output, and the angular velocity signal is a value having a code assigned to 0 as the origin. Become. That is, when the angular velocity signal is A / D converted by the A / D converter 67, it is possible to detect the state where the angular velocity is 0 even if there is no reference value indicating 0.

Next, a concrete calculation in the image moving speed calculation unit 54 in the camera shake prevention CPU 66 will be described. Broadly speaking,
Two operations are performed. First, the first calculation is performed once at the beginning, and the object distance information and the focal length information of the photographing lens 31 sent from the camera control unit 34 and the sensitivity correction data of the sensor are used to calculate the angular velocity image velocity conversion coefficient. γ
Is calculated as γ = α · f · (1 + β) · (1 + β).

The second calculation is a calculation which is performed almost regularly for detecting a camera shake. That is, by using the angular velocity image velocity conversion coefficient γ obtained by the first calculation, from the predicted camera shake angular velocity signal ω _pr , the camera shake image moving velocity v _pr
Is _calculated as v _pr = γ · ω _pr .

By the way, as shown in FIG. 7, the image stabilization unit 48 includes an image stabilization drive signal generator 55, an image stabilization drive motor 56, an image stabilization optical unit 57, and a corrected drive image velocity detector 58. It consists of Then, the camera shake prevention unit 48 causes the camera shake correction drive signal generation unit 55 to drive the camera shake correction drive motor 56 based on the image movement speed signal from the camera shake detection processing unit 47 that detects camera shake. As a result, the camera shake correction optical section 57 in the imaging lens 31 is moved, and the optical axis of the subject image passing through the imaging lens 31 is moved. In this way, the movement of the optical axis due to the blurring is canceled and the movement of the subject image on the surface of the film 35 is suppressed, so that the blurring during the photographing is reduced.

The camera shake correction drive signal generating section 55 compares the image moving speed due to the camera shake from the camera shake detection processing section 47 with the image moving speed due to the correction driving of the camera shake correction optical section 57, and supplies the power corresponding to the difference. Image stabilization drive motor 56
Apply to. Therefore, the image stabilization drive motor 56,
A correction drive image velocity detection unit 58 that detects the image movement velocity due to the correction drive is connected to any of the image stabilization optical units 57.

The electric power applied to the camera shake correction drive motor 56 is approximately proportional to the difference between the two speeds. This is because the camera shake correction drive motor 5 produces an acceleration corresponding to this difference.
This is because the occurrence of 6 enables smooth camera shake correction driving.

The camera shake correction optical section 57 includes the photographing lens 31.
Which is an optical lens having two parallel surfaces. As shown in FIGS. 12 and 13, when the parallel glass plate 69 is tilted from the position perpendicular to the optical axis,
The optical axis can be shifted parallel to the original optical axis. The parallel glass plate 69 is attached to the gimbal mechanism 71 by a shaft 70 so as to be rotatable in the direction of the arrow in the figure. The gimbal mechanism 71 is rotatable by a shaft 72 in the direction of the arrow shown.

The camera shake correction optical section 57 also includes a gimbal mechanism 71 and a gimbal drive force transmission member (not shown) for converting displacement caused by rotation of the camera shake correction drive motor 56 into rotation of the gimbal frame. There is. Parallel glass plate 6
9 is attached to the gimbal mechanism 71 so as to be freely rotatable in two axial directions.

Next, the flow of operation of the camera shake prevention device 43 will be described with reference to the <camera shake prevention> routine shown in FIG. In step S3 of FIG. 8, when the camera control unit 34 issues an instruction to start the detection of camera shake,
In step S21, the image stabilization control unit 46 of the image stabilization device 43 receives this signal.

Next, in step S22, the object distance information and the photographic lens 3 necessary for obtaining the image velocity of camera shake are obtained.
The focal length information of No. 1 is received from the camera control unit 34 that controls the main body of the camera 30. Further, the angular velocity sensitivity correction value α of the output of the angular velocity amplification unit 51, the output variation value δ of the differential amplifier when the reference voltage of the angular velocity amplification unit 51 is changed, and constant information for the high pass time constant of the angular velocity signal high pass filter processing unit 52. As the initial value kh _s and the final value kh _e of the HPF coefficient, and the value Δkh that is changed in one calculation, the coefficient for prediction in the angular velocity prediction calculation unit 53, and the accuracy of the camera shake correction drive signal generation. The correction value information for the is received from the camera control unit 34.

The correction data and the control data are received from the camera control unit 34. When the correction data is treated as the adjustment data for each camera, an EEPROM or the like connected to the control means for controlling the entire camera is used. This is because the non-volatile readable and writable storage medium can be used to store the correction data and control data necessary for preventing and correcting camera shake, which leads to cost reduction and space saving of the entire camera. Of course, when it is not necessary, a non-volatile memory may be connected to the camera shake prevention control unit 46 and used.

Next, in step S23, the angular velocity sensor section 50 and the angular velocity detection IC 65 are powered on. Subsequently, in step S24, the angular velocity image velocity conversion coefficient γ is calculated and obtained from the correction data.

In step S25, the HPF calculation register V _hpf , HPF coefficient kh, prediction data storage pointer, data accumulation counter, differential amplifier reference voltage generator 6
RAM and registers for various calculations such as reference voltage data Vk for determining the output voltage from 2 are initialized.

As the initial value of the reference voltage Vk, the central value of the fluctuation range is set. Further, the initial value of the HPF coefficient kh is the data kh _s received from the camera control unit 34. Further, a flag (f_vok) indicating whether or not the output of the differential amplifier 61 is within an appropriate range, a prediction data accumulation flag (f_prdct) indicating whether or not the shake signal used for prediction is sufficiently accumulated, and the magnitude of shake Is initialized (cleared), such as a large angular velocity flag (f_brl) indicating that is greater than or equal to a predetermined value, and a small angular velocity flag (f_brs) indicating that the magnitude of blur is less than or equal to another small predetermined value. It

When camera shake is detected around a plurality of x, y, and z axes, variables for each axis, such as a register for storing shake information and a flag indicating the size of shake, are respectively set. It is initialized.

Next, in step S26, the differential amplifier reference voltage generator 62 is instructed to output the reference voltage data Vk in the initial value state. As a result, the differential amplifier reference voltage generator 62 in the angular velocity amplifier 51 outputs a predetermined reference voltage.

Then, in step S27, the process stands by until a predetermined time (first predetermined time) elapses after the sensor is powered on. This is the work of waiting for the rise time of the sensor and IC. This time may be about 10 to 30 msec.

Then, in step S28, continuous execution of A / D conversion is started. From this point onward, until the A / D change is stopped, the A / D conversion result register is read, and the angular velocity signal Vd becomes available as the latest A / D conversion result.

Next, in step S29, the process stands by until a predetermined time (second predetermined time) elapses. This is a work for earning A / D conversion time in which a specified voltage is output by the D / A converter of the differential amplifier reference voltage generation unit 62 and this output is digitized. This is about several hundred μ
It may be about sec.

Next, in step S30, A / D conversion reading is performed to obtain data in which the analog angular velocity signal Va of the differential amplifier 61 is digitized into the angular velocity signal Vd. Then, in step S31, a <reference voltage change> routine is executed.

In the routine of step S31, the differential amplifier reference voltage generating section 62 is controlled by the output of the differential amplifier 61.
Voltage is controlled. Further, in this routine, it is determined whether or not the output of the differential amplifier 61 is within a range in which it is properly controlled. This is because the output of the differential amplifier 61 is saturated in the initial state, and it may not be possible to know whether the output voltage is in the proper range even if the reference voltage is changed by ΔVk. When it is within the proper range, a flag (f_vok) indicating it is set.

Further, when the reference voltage is changed, it is corrected to the W register which is the work RAM (not shown) by using the output fluctuation value data δ of the differential amplifier 61 in accordance with the rising / falling direction. The digital angular velocity signal is stored. That is, W = Vd−δ or W = Vd + δ. When the reference voltage is not changed, Vd is stored as it is. That is, W = Vd.

Next, in step S32, the flag (f_vok) is checked to determine whether the output of the differential amplifier 61 is within the proper range. Differential amplifier 61
If the output of is not within the appropriate range, the process returns to step S29, and the operations of steps S29 to S32 are repeated.

On the other hand, when it is detected in step S32 that the output of the differential amplifier 61 is within the proper range,
The process proceeds to step S33, in which a timer for setting the passage of time is set so that the subsequent calculation and control are performed at predetermined time intervals. This cycle time is the third predetermined time. This may be about 1 to 2 msec.

Succeedingly, in a step S34, a register for HPF calculation is set as a camera shake signal correction.
This is the setting of the previous input value for the input to the HPF calculation, that is, the previous digitized angular velocity signal Vd '. Since the substantial correction result of the camera shake signal has already been assigned to the work register W in the <reference voltage change> routine, Vd '= W is set. That is, the corrected angular velocity signal is the variable V
It is stored in d '.

Next, in step S35, it is awaited whether the third predetermined time has elapsed. In this step S35,
If the elapse of the third predetermined time is confirmed, the process proceeds to step S36, and the third time is again set in order to elapse the next third predetermined time.
The scheduled time timer is set.

In step S37, A / D conversion reading is performed. That is, the latest analog angular velocity signal Va of the differential amplifier 61 is acquired as data digitized into the angular velocity signal Vd.

Next, in step S38, the <reference voltage change> routine is executed, and the voltage of the differential amplifier reference voltage generating section 62 is controlled by the output of the differential amplifier 61. The work W register is processed in the same manner as this routine described above.

Then, in step S39, the <HPF calculation> routine is executed. As a result, the previous and current A / D data registers Vd ′, Vd, and the register V _hpf in which the previous HPF calculation result is stored (the initial value (0) is stored if the HPF calculation has never been performed). , And the HPF coefficient kh is used to perform a high-pass filter operation. Basically, if this result is H, then H = Vd-Vd '+ _kh.Vhpf . However, the processing is slightly different depending on the elapsed time and the magnitude of the angular velocity signal.

The result H is the HPF calculation register V _hpf
Is assigned to. As a result, the latest HPF is _added to V _hpf.
The calculation result is stored. V _hpf = H Next, in step S40, camera shake signal correction is performed. Substantially, the work register W set by the <reference voltage change> routine stores a value that has been largely corrected to the latest digital angular velocity signal Vd. This is substituted in the previous A / D data register Vd used in the next HPF calculation, and Vd '= W is set. That is, the corrected angular velocity signal is the variable V
It is stored in d '.

In step S41, the <HPF calculation> result is accumulated for accumulating the past data used in the prediction calculation (prediction data storage storage). Further, when the accumulated amount reaches the required number, the predicted data accumulation flag (f_
prdct) is set.

Then, in step S42, the magnitude of the camera shake angular velocity signal is determined from the result of <HPF calculation>.
Here, when it is larger than the first blur predetermined value, the large angular velocity flag (f_brl) indicating the large blur state is set. When the value is smaller than the second predetermined shake value which is smaller than the first predetermined shake value, the small angular velocity flag (f_brs) indicating the small shake state is set.

Next, in step S43, the <prediction calculation> routine is executed. As a result, the high-pass filtered angular velocity signal V _hpf is converted into the predicted angular velocity signal ω _pr . Then, in step S123, the <image velocity conversion calculation> routine is executed. Thus, the angular speed image rate conversion coefficient γ is used that has been obtained in step S24, the prediction angular velocity signal ω blur image moving velocity V _pr from _pr
Is required.

Thereafter, in step S45, the obtained image moving speed V _pr , the flag indicating the magnitude of blurring, and the like are sent to the camera control unit 34. Then, step S46
Then, the position of the image stabilization optical unit 57 of the image stabilization unit 48 is detected.

Next, in step S47, the camera shake prevention unit 4
8, the image movement speed V _cp is the correction drive image speed detection unit 58 with respect to the moving speed of the image by the drive of the image stabilization optical unit 57.
Used in and detected by.

Subsequently, in step S48, it is checked whether or not a camera shake correction instruction is issued from the camera control unit 34. If the instruction is given, the process proceeds to step S49, and the <correction drive control amount calculation> routine is executed. On the other hand, if no instruction for camera shake correction has been issued, the process proceeds to step S50, and the <centering drive control amount calculation> routine is executed. After that, the process proceeds to the <drive control amount output> routine of step S51.

After the execution of the <drive control amount output> routine in step S51, the process proceeds to step S52, and it is checked whether or not the camera control section 34 has given an instruction to end camera shake detection. If there is an instruction to end the camera shake detection, the process returns to step S21. On the other hand, if there is no instruction to end the camera shake detection, the process returns to step S35, and the processing operation described above is continuously performed every third predetermined time.

Next, the operation of the <reference voltage change> routine will be described in more detail with reference to the flowchart of FIG. This is the operation of the reference voltage controller 63. First, in step S61, the digitized angular velocity amplified signal Vd output from the differential amplifier 61 is stored in the work register W. Then, in step S62,
The angular velocity amplified signal Vd and the predetermined value Vd _H are compared. Here, if the Vd> Vd _H, reference voltage data Vk is higher by a predetermined value DerutaVk. Therefore, whether Vk + ΔVk is possible, that is, whether the value of Vk + ΔVk becomes too large and the accuracy of the register deviates is determined in the following step S63.
Can be found at. If an overflow occurs in this step S63, this routine is exited. On the other hand, if the calculation is possible without overflowing, the following step S6
At 4, Vk = Vk + ΔVk is changed. If this value is used to instruct the differential amplifier reference voltage generator 62, which is a D / A converter, to output a new Vk, the output of the differential amplifier 61 should decrease by the output fluctuation value data δ. Is.

Next, in step S65, the work register W is decremented by the output variation value data δ of the differential amplifier. W = In Vd - [delta step S62, if the comparison result of the angular velocity amplified signal Vd and the predetermined value Vd _H is not Vd> Vd _H, the process proceeds to step S66. In step S66, the angular velocity amplified signal Vd is compared with the predetermined value Vd _L. Where V
If d <Vd _L , the reference voltage data Vk has a predetermined value ΔV.
Lowered by k. Therefore, is Vk-ΔVk possible?
That is, it is checked in the subsequent step S67 whether the value of Vk-.DELTA.Vk does not become negative. If it becomes negative, this routine ends.

On the other hand, if the calculation in step S67 is possible within the range of positive values, the process proceeds to step S68 and Vk = Vk-ΔVk and the reference voltage data are changed. Using this value, D /
If the differential amplifier reference voltage generator 62, which is an A converter, is instructed to output a new Vk, the output of the differential amplifier 61 should rise by the output fluctuation value data δ.

Then, in step S69, the work register W is decremented by the output fluctuation value data δ of the differential amplifier 61. W = Vd + δ Next, in step S70, an output is instructed to the differential amplifier reference voltage generator 62 with a new Vk, and then this routine ends.

Further, in the step S66, Vd
If it is not Vd _L , the output of the differential amplifier 61 is within a predetermined proper range. That is, Vd _L ≤Vd ≤Vd _H. In this case, the process proceeds to step S71, the flag f_vok is set to indicate that the output of the differential amplifier 61 is within the proper range, and then this routine ends.

Here, a more specific example will be described with reference to FIG. Now, the output range of the differential amplifier 61 is 0
To 5V. If the amplification factor of the differential amplifier 61 is 20 times and the decomposition ΔVk of the change of the reference voltage is 0.1V, the output fluctuation value data δ is 2V. At this time, the predetermined value Vd _H is set to 4V and the predetermined value Vd _{L is set} to 1V.
The transition of the camera shake signal is digitized in discrete time, and the value at that time is shown by a white circle in the figure.

At time t ₀ , if the angular velocity signal Vd exceeds 4V, the reference voltage is changed and the output is reduced by 2V (δ). This value is the acquisition time t ₁ of the next A / D data.
Can be obtained at. The difference in the angular velocity signals between times t ₀ and t ₁ is
Although it is physically “A” in the figure, this is the differential amplifier 61.
This is because the reference voltage of is changed, and is substantially “B” in the drawing. To correct this, the value of the work register W is used.

Next, the operation of the <HPF calculation> routine will be described. As shown in the above equation, the high-pass filter calculation is performed by using the angular velocity signal as Vd, the previous angular velocity signal as Vd ′, the high-pass calculation result as V _hpf , and the previous high-pass calculation result as V _hpf ′, the previous high-pass calculation. When the weighting factor for the results and calculating HPF coefficient kh _w, can be described as _{V hpf = Vd -Vd '+ kh} w · V hpf'.

Therefore, first, the calculation HPF coefficient kh _w is set. The provisional HPF coefficient is set to kh. The HPF coefficient kh is based on the information received from the camera control unit 34 as constant information for the high pass time constant. This value is the initial value of the HPF coefficient kh _s
And the final value kh _e , the value Δk to be changed per operation
h.

When the angular velocity sensor rises, the drift component is large. Further, the drift component becomes smaller as the time becomes stable. Therefore, an HPF coefficient having a relatively small time constant is initially used, and an HPF coefficient having a large time constant is used as the sensor gradually stabilizes. The initial value of the HPF coefficient is k, as shown above.
h _s .

If kh is smaller than the final value kh _e , the calculation of kh = kh + Δkh is performed every time the HPF calculation is performed. If kh> kh _e , then kh = kh _e to prevent the HPF coefficient from becoming larger than the final value. This value kh is the calculation HPF coefficient kh.
assigned to _w .

Kh _w = kh In this way, as the number of calculations progresses, the coefficient of the high-pass filter calculation increases, and the low-frequency component passes gradually.

The relationship between the HPF coefficient kh and the cutoff frequency f _c of the high-pass filter is kh = 1-2 · π · Δt · f _c, where Δt is the calculation time interval.

The value of the HPF coefficient is preferably set to 3 to 10 Hz immediately after the start of calculation, and finally to about 0.1 Hz, after being corrected to the cutoff frequency. 3Hz immediately after operation start, the final and 0.1 Hz, the value of the HPF coefficient, when the interval to be performed the operation of _{1msec, kh s = 1-2 · π} · 0.001sec · 3Hz = 0.9811504441 kh _{e = 1-2 · π · 0.001sec ·} 0.1Hz = is 0.9993716815, the variation of the HPF coefficient of per, and the _{Δkh = 0.0000305176, (kh e -kh} s) / Δkh = 597, which is the final value about 0.6 seconds after the start of the calculation.

If kh is equal to the final value kh _e , it is determined whether the HPF coefficient kh is used in the state of the small angular velocity flag (f_brs). Here, if the small angular velocity flag (f_brs) is set and it is shown that the shake is small, then kh _w = kh (= kh _e ), and if the flag is in the reset state, then kh _w = 1 To be done.

This is because the sensor drift in a stable state to a certain extent is a very small and slow variation compared to the vibration angular velocity such as camera shake, so that it is effective if the HPF is applied to a relatively large angular velocity signal. This is because the rate of removal of the angular velocity component becomes high and the angular velocity may not be detected effectively. For a relatively small blur,
Since the drift component is large with respect to the shake angular velocity, the HPF can effectively remove the drift.

Therefore, the HPF calculation is performed only when the angular velocity signal is small, and the HPF calculation is performed when the angular velocity signal is large.
The F coefficient is set to the maximum value of 1, and the offset removal function is suppressed.

The operation of the <HPF calculation> routine will be described below with reference to the flowchart of FIG. First,
In step S81, the HPF coefficient kh and the final HPF
The coefficient kh _e is compared. If the coefficient kh is smaller, the process proceeds to step S82. Then, in this step S82, (kh + Δkh) is compared with the final value kh _e . If it is larger than kh _e , the process proceeds to step S83 and H
Kh _e is assigned to the PF coefficient kh.

On the other hand, in the step S82, (kh +
If Δkh) is smaller than the final value kh _e , step S8
In step 4, (kh + Δkh) is assigned to the HPF coefficient kh. As a result, when the <HPF calculation> routine is executed next time, the value of kh is slightly larger.

Next, in step S85, the calculation HP
Kh is substituted for the F coefficient kh _w . After that, step S
At 86, the HPF calculation result is substituted into the register H. In this case, the register V _hpf of the angular velocity signal, which is the high-pass calculation result, contains the previous high-pass calculation result.

[0126] _{H = Vd -Vd '+ kh w} · V hpf Next, in step S87, the high-pass operation result V _hpf
Is assigned to. V _hpf = H In this way, when the latest HPF angular velocity signal V _hpf is obtained, this <HPF calculation> routine ends.

By the way, in the step S81, the HPF
When the coefficient kh and the final HPF coefficient kh _e are compared, k
If h is larger than kh _e (because the maximum value of kh is kh _e ), the process proceeds to step S88.

In step S88, the small angular velocity flag (f_brs) is checked for the magnitude of the angular velocity signal. Here, if the small angular velocity flag (f_brs) is set, the process proceeds to step S85, and the above-described calculation operation and the like are performed. On the other hand, if the small angular velocity flag (f_brs) is not set in step S88, the process proceeds to step S89. The calculation HPF coefficient kh _w is 1
After that, the process proceeds to step S86 to perform the above-described arithmetic operation and the like.

Although the detailed description is omitted here,
The correction drive control amount calculation routine, the <centering drive control amount calculation routine>, and the <drive control amount output> routine are executed by the camera shake correction drive signal generation unit 55.

In the <correction drive control amount calculation> routine, the <image velocity conversion calculation> -processed camera shake detection processing unit 4 is executed.
The image moving speed v _pr due to the camera shake from 7 and the image moving speed v _cp due to the correction drive of the camera shake correction optical unit 57 are compared,
The electric power applied to the image stabilization drive motor 56 is determined according to the difference. This is the polarity direction of the voltage, the duty ratio of PWM drive, and the applied voltage.

In the <correction drive control amount calculation> routine, when the position of the camera shake correction optical unit 48 is not corrected and driven, the position information and the image moving speed v _cp are set to the median value.
The electric power applied to the image stabilization drive motor 56 is calculated based on This is also the polarity direction of the voltage, the duty ratio of PWM drive, and the applied voltage.

In the <drive control amount output> routine, the voltage which is the power information applied to the camera shake correction drive motor 56 determined above, the duty ratio of the PWM drive, and the polarity direction information of the applied voltage are used. The drive circuit of the motor is controlled.

By the way, in the above-described embodiment, FIG.
The arithmetic processing signal size determination unit 16 for determining the magnitude of the signal to be subjected to the HPF arithmetic processing shown in (a) sets the small angular velocity flag (f_brs), and step S depending on the value.
It is configured by the branch judgment at 88, and the first arithmetic unit 1
7 and the second calculation unit 18 are configured by a program in which the calculation HPF coefficient kh _w is set to kh _w = kh (= kh _e ) or kh _w = 1 to perform calculation, and the non-linear HPF calculation unit 12 An example composed of

Another example of the <HPF calculation> routine will be described below. This is an embodiment using the non-linear HPF calculator 12 having the configuration shown in FIG. This non-linear H
The PF calculator 12 includes a subtraction-type attenuation processor 19 that performs an attenuation process that is not proportional to the magnitude of the signal, and the HPF calculator 2
It consists of 0 and.

The HPF characteristic can also be obtained by subtracting h ′ so as to slightly reduce the value, without using the coefficient kh that attenuates the signal used in the above-described example with a linear characteristic. This eliminates the need for multiplication in the HPF calculation, thus speeding up the process. Further, it becomes possible to use a CPU which has a low function but is easy to cost.

For example, the camera shake angular velocity signal is usually ± 10.
It is deg / s (= 0.1745 rad / s) or less, but it is assumed that this is ± ffffH digitally as a result of A / D.

Assuming that the angular velocity is 10 deg / s and the focal length is 200 mm and the exposure time is 1/32 seconds, the blur is 200 mm * 0.1745 rad / s * 1/32 = 1. 1 mm occurs. Further, when the allowable value of blurring is 50 μm, this value is 22 times the allowable value. That is, the allowable angular velocity under this condition is 0.45 deg / s = 10 deg / s / 22. Expressed in the above digitized unit, 0b
a2H.

The above-mentioned multiplication type HPF coefficient is an initial value,
A stable time, respectively, is _{0.9811504441 (f c 3Hz) 0.9993716815 (} f c 0.1Hz). Multiplying this by ffffH gives fb2cH ffd6H, respectively.

When 0ba2H is multiplied by this coefficient,
They are 0b6aH and 0ba0H, respectively. The difference from 0ba2H is 0038H 0002H, respectively.

As can be seen from these, if the absolute value of the digital angular velocity signal is smaller than 0ba2H, 2
If subtracted (within a range not negative), the high-pass filter 0.1Hz equivalent cutoff frequency (f _c). If 38H is subtracted, a characteristic equivalent to f _c 3 Hz can be obtained.

The filter that multiplies the HPF coefficient has the same effect as that of the CR high-pass filter composed of a resistor and a capacitor. However, the filter that subtracts such a fixed amount is a CR filter composed of a resistor and a capacitor. It is possible to obtain a high-pass filter having a non-linear characteristic with respect to the input waveform or the output waveform which is not the configuration of FIG.

That is, in the above example, a sufficient HPF effect cannot be obtained for the value of ffffH. This is a very convenient characteristic for the HPF for removing the drift of the signal including the drift of the angular velocity sensor etc., as described above. In other words, in order to remove the signal component that would occur due to drift by subtraction,
It does not distort the angular velocity component of vibration unnecessarily small.

FIG. 18 is a flow chart for explaining another operation example of the <HPF calculation> routine. First, in step S91, the HPF variable kh 'and the HPF constant kh are set.
_e ′ is compared. Here, kh ′, kh _e ′, Δkh, etc., which will be described later, are the HPF coefficient data kh, kh used in the embodiment shown in the flowchart of FIG.
Like _e and Δkh, the data is handled in the outer program loop. However, in the example of the flowchart shown in FIG. 18, in order to perform addition and subtraction, HPF coefficient is used instead of HPF coefficient.
It is treated as a PF variable and HPF constant.

[0144] HPF coefficient kh is greater than 'is the final value kh _e being sent from the camera control unit 34' proceeds to step S92, is checked whether it is kh '-Δkh'<kh _e 'is. .DELTA.kh 'is fluctuation data per one calculation of the HPF variable kh' sent from the camera control unit 34. Where (kh'-Δkh
) Is smaller than kh _e ′, the process proceeds to step S93, and kh _e ′ is substituted for kh ′. On the contrary, (kh
If '-Δkh) is kh _e' larger, the process proceeds to step S94, 'the (kh' kh is -Derutakh) is substituted.

Here, unlike the case of the flowchart of FIG. 17, the HPF variable has a larger initial value and gradually becomes smaller. This is also to gradually weaken the removal power of the DC component and the low frequency component by the HPF.

Step S93 or step S9
After kh 'is reset in step 4, step S95
In, 'the, kh' calculation work register kh _w is substituted. Next, in step S96, it is checked whether the previous HPF calculation result of the HPF calculation register V _hpf is positive or negative. If the calculation result is positive, the process proceeds to step S97, and X = V _hpf −kh _w ′ is assigned to the work register X.

In this work register X, data for considering the past data used in the HPF calculation is stored. That is, the HPF effect is obtained by slightly estimating the previous HPF calculation result and adding the change value of the current angular velocity signal.

Next, at step 98, it is checked whether the work register X is positive or negative. Here, if the work register X is positive, the process proceeds to step S99, and the work register H
Is assigned to H = Vd-Vd '+ X. Then, in step S100, the value of the work register H is substituted into the HPF calculation register V _hpf . Then, the current HPF calculation, that is, this routine is finished.

If it is determined in step S98 that the work register X> 0 is not satisfied, the flow advances to step S103 to perform the calculation of H = Vd-Vd '. This is because the previous HPF calculation result is sufficiently small and it is not necessary to consider the past history. Then, after this step S103 is executed,
It proceeds to step S100.

In step S96, the HP
_If the previous HPF calculation result of the F calculation register V _hpf is not positive, the process proceeds to step S101. Then, in this step S101, X = V _hpf + kh _w ′ is substituted into the work register X in order to perform the calculation by changing the processing of the sign and the case of being positive.

The sign of the result is then checked in step S102. Here, the sign of the work register X is V _hpf
Similarly, if it is negative, the process proceeds to step S99, and if the signs are different, the process proceeds to step S103, and the above-described processing operations are performed.

Further, in the above step S91, kh 'is k
If it is equal to or smaller than h _e ′ (though it does not occur if it is smaller in the process of step S93), the process proceeds to step S104, and the angular velocity flag (f_
brs) is examined.

Here, if the flag is set, the flow advances to step S95 to perform the above-mentioned arithmetic operation and the like. on the other hand,
If the flag is not set in step S104, the process proceeds to step S105, and calculation is performed so that the HPF effect is not obtained. Specifically, H = Vd-Vd '+ _Vhpf is assigned to the work register H. After this, the process proceeds to step S100, and HP
The F angular velocity data V _hpf is set, and this routine ends.

As a result, due to the non-linear relationship, the HPF operates when the angular velocity is small and does not operate when the angular velocity is large, so that the angular velocity signal is not distorted more than necessary.

Next, as a second embodiment of the present invention, an example in which the vibration detecting device is applied to a direction detecting device for a navigation system of a vehicle will be described. FIG. 19 is a block diagram showing a configuration of an example in which the vibration detecting device according to the present invention is applied to a direction detecting device for a navigation system of a vehicle.

In the figure, the direction detecting device comprises an angular velocity sensor unit 74, an angular velocity amplifying unit 75, an angular velocity signal high-pass filter processing unit 76 and an angular velocity integration calculating unit 77, and the rotational speed of the vehicle. Is detected and integrated to output the direction of the vehicle.

The angular velocity output detected by the angular velocity sensor section 74 is amplified by the angular velocity amplifying section 75 into a predetermined signal. Then, the amplified signal is subjected to high-pass arithmetic processing by the angular velocity signal high-pass filter processing unit 76, and further, this signal is temporally integrated by the angular velocity integration arithmetic unit 77.
Thereby, the direction signal is obtained.

The angular velocity sensor section 74 and the angular velocity amplification section 7
5. The angular velocity signal high-pass filter processing unit 76 has the same configuration as the angular velocity sensor unit 50, the angular velocity amplification unit 51, and the angular velocity signal high-pass filter processing unit 52 shown in the example of the camera shake detection device described above. The same operation is performed.

When the power is turned on, the vehicle is in a substantially stopped state, during which the time constant of the HPF calculation changes to have a predetermined HPF characteristic. After this, the drift is removed when the signal changes slowly, and the HPF characteristic disappears when the direction of the vehicle changes. Therefore, the angular velocity can be detected effectively and without any distortion.

As described above, by integrating the accurate angular velocity signal having no drift, the accurate angular direction can be detected. A publicly known integrator may be used to perform the integral calculation. Also, if processed digitally, the angle θ
May be performed for each Δt as a calculation of θ = Σ (ω · Δt) using the angular velocity ω and the discrete time interval Δt of the calculation.

According to the above embodiment of the present invention, the following constitution can be obtained. (1) A vibration information detecting unit that detects vibration applied from the outside as vibration information, and a non-linear removal characteristic that is not proportional to the size of the detected vibration information, and based on the size of the vibration information A vibration detecting apparatus comprising: a low frequency component removing unit that removes a low frequency component while changing a removal rate for removing a predetermined low frequency component mixed in the vibration information.

(2) The vibration information detected by the vibration information detecting means is camera shake information, and the low frequency component removing means performs low frequency component removing calculation for preventing camera shake during exposure of the camera. The vibration detecting device according to (1) above.

(3) The camera shake information detecting means for detecting the vibration applied from the outside as the camera shake information, and the non-linear removal characteristic not proportional to the size of the detected camera shake information, are mixed in the camera shake information. And a low frequency component removing means for removing a predetermined low frequency component.

(4) The vibration detecting device as described in (3) above, wherein the camera shake information detecting means is an angular velocity sensor. (5) Camera shake information detecting means for detecting vibration applied to the camera body as camera shake information, amplifying means for preventing saturation due to the detected camera shake information being larger than a predetermined value, and the above-mentioned detected camera shake information. And a low-frequency component removing unit that removes a predetermined low-frequency component that is mixed in the information amplified by the amplifying unit and that has a non-linear characteristic that is not proportional to the magnitude of the hand-shake information. Information detection device.

(6) The amplifying means includes a differential amplifier for comparing the voltage value from the camera shake information detecting means with a predetermined reference voltage value, and the reference voltage value so that the output of the differential amplifier is not saturated. A reference voltage control means for controlling the output of the differential amplifier within a predetermined range, and a correction means for correcting the output of the differential amplifier according to the amplification factor of the amplifier when the output of the differential amplifier is controlled within the predetermined range. The camera shake information detecting device according to (5) above, which further comprises:

[0166]

As described above, according to the present invention, the HPF
It is possible to provide a vibration detection device that improves a filter to effectively remove an offset component and a drift component included in a vibration signal and does not remove a low frequency component of the vibration signal more than necessary.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a vibration detecting device of the present invention.

2 is a non-linear HPF calculation unit 12 of the vibration detection device of FIG.
It is a figure showing an example of composition.

FIG. 3 is an external perspective view showing a configuration example of a camera having a camera shake prevention device to which the vibration detection device according to the present invention is applied.

FIG. 4 is a block diagram showing a schematic configuration of a camera having a camera shake prevention device to which the vibration detection device according to the present invention is applied.

5 is a flowchart illustrating a rough operation of the camera control unit 34 in FIG.

FIG. 6 is a block diagram showing a detailed configuration of a camera shake prevention device 43 in FIG.

7 is a block diagram showing a detailed configuration of a camera shake detection processing unit 47 and a camera shake prevention unit 48 in FIG.

8 is a block diagram showing an example of a configuration of an angular velocity amplification section 51 of FIG.

9 is a block diagram showing a more specific configuration example of the angular velocity amplification section 51 of FIG.

FIG. 10 is a diagram illustrating an operation of a reference voltage control unit 63.

11 is a block diagram showing another configuration example of the camera shake prevention CPU 66 in FIG.

FIG. 12 is a perspective view showing a schematic configuration of a taking lens 31.

FIG. 13 is a diagram for explaining the operation of the parallel glass plate 69 of the taking lens 31.

FIG. 14 is a flowchart illustrating the operation of a <shake prevention> routine.

FIG. 15 is a flowchart illustrating an operation of a <reference voltage change> routine.

FIG. 16 is a characteristic diagram of an angular velocity signal Vd.

FIG. 17 is a flowchart illustrating the operation of a <HPF calculation> routine.

FIG. 18 is a flowchart illustrating another operation example of the <HPF calculation> routine.

FIG. 19 is a block diagram showing a configuration of an example in which the vibration detecting device according to the present invention is applied to a direction detecting device for a navigation system of a vehicle.

[Explanation of symbols]

11 ... Vibration detection unit, 12 ... Non-linear HPF (high-pass filter) calculation unit, 13 ... Shake detection unit, 14 ... Angular velocity sensor, 15 ... Integral calculation unit, 16 ... Calculation processing signal size determination unit, 17 ... First calculation unit, 18 ... 2nd calculating part, 19 ... Subtraction type attenuation processing part, 20 ... HPF calculating part, 30 ... Camera, 3
DESCRIPTION OF SYMBOLS 1 ... Photographic lens, 32 ... Viewfinder, 33 ... Release button, 34 ... Camera control part, 35 ... Film, 36 ... Focus adjusting device, 37 ... Photometric device, 38 ... First release switch (1stRsw), 39 ... Second release switch ( 2ndRsw), 40 ... Exposure device, 41 ... Film feeding device, 42 ... Display unit, 43 ... Shake prevention device,
44 ... Power supply unit, 46 ... Shake prevention control unit, 47 ... Shake detection processing unit, 48 ... Shake prevention unit, 50 ... Angular velocity sensor unit, 51 ... Angular velocity amplification unit, 52 ... Angular velocity signal high-pass filter processing unit, 53 ... Angular velocity prediction Calculation unit, 54 ... Image moving speed calculation unit, 55 ... Shake correction drive signal generation unit, 56 ...
Image stabilization drive motor, 57 ... Image stabilization optical unit, 58
Compensation drive image velocity detection unit, 61 ... Differential amplifier, 62 ... Differential amplifier reference voltage generation unit, 63 ... Reference voltage control unit, 64
... Output correction unit, 65 ... Angular velocity detection IC, 66 ... Shake prevention CPU.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI G03B 17/00 G03B 17/00 (58) Fields investigated (Int.Cl. ⁷ , DB name) G01C 19/00-19/72

Claims (6)

(57) [Claims] 1. A vibration information detecting means for detecting a vibration obtained from the outside as vibration information, a low frequency component removing means for removing a predetermined low frequency component mixed in the vibration information, and the low frequency component. Changing means for changing the cutoff frequency of the removing means with the passage of time , wherein the low-frequency component removing means is provided by the vibration information detecting means.
Change value of the detected angular velocity signal and the previous calculation result
By multiplying by a predetermined coefficient and adding, a predetermined low frequency
The number component is removed, and the changing means can change the coefficient.
The vibration detection device is characterized in that the cutoff frequency is changed according to. 2. A vibration applied from outside is used as vibration information.
And a vibration information detecting means for detecting a predetermined low frequency component mixed in the vibration information.
Low-frequency component removing means, and the low-frequency component removing means is provided by the vibration information detecting means.
The calculated value of the previous time is used as the change value of the detected angular velocity signal.
By adding the results of subtraction to make it smaller,
A vibration detector characterized by removing a predetermined low frequency component . 3. A cutoff frequency of the low frequency component removing means.
Changing means for changing the wave number with the passage of time, wherein the changing means is for calculating by the low frequency component removing means.
When changing the subtraction amount from the previous calculation result
Accordingly, the cutoff frequency is changed . The vibration detecting device according to claim 2 , wherein the cutoff frequency is changed . 4. The low frequency component removing means is a high pass filter.
The low frequency component that includes the filter means is the offset
Component, drift component, or a predetermined amount of DC component, etc.
Vibration detecting apparatus according to claim 1, 2, characterized in that that. 5. The above-mentioned changing means is the above-mentioned with the passage of time.
The vibration detection device according to claim 1 , wherein the cutoff frequency is lowered . 6. The magnitude of the detected vibration information is determined.
Vibration information larger than a predetermined amount by the above-mentioned judging means.
If it is determined that the cut
4. The off frequency is reduced, as claimed in claim 1.
The vibration detection device described in.