JPH11174511A - Optical device provided with image blur correcting function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change the frequency characteristic of a circuit, as we desired, without using a microcomputer capable of executing high-speed processing and other expensive electrical parts. SOLUTION: This optical device is provided with an angular velocity detecting means for detecting the change in an angle of the optical axis of an optical system as an angular velocity, a signal processing means for executing the signal processing of a signal outputted from the angular velocity detecting means with a fixed frequency characteristic, an optical axis changing means for changing the optical axis, an optical axis change driving means for driving the optical axis changing means according to the signal outputted from the signal processing means and the microcomputer for controlling various kinds of components in the device. Then, the signal processing means makes the frequency characteristic of a switching means operated to open/close variable with a break-make ratio of the switching means and the microcomputer has the function of outputting variable-duty consecutive pulse signals S2 and supplies these consecutive pulse signals, as opening/closing operation signals for the switching means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an optical device having an image blur correction function, such as a camera.

[0002]

2. Description of the Related Art Hitherto, an optical device such as a camera having a function of correcting an image blur caused by a camera shake or the like has been known. More specifically, an image blur generated due to camera shake vibration or the like is detected as information such as acceleration or angular velocity by a vibration detection sensor provided in the device, and the image blur is detected on an imaging surface or based on such blur information. An optical device having a mechanism for moving or changing the whole or a part of the optical system of the device so as to negate it on the observation surface has been realized. JP-A-1-130144, JP-A-7-261233 or JP-A-8-13695
No. 2 is a proposal example of such a device.

[0003]

According to the above proposed apparatus, an optical apparatus having a function of correcting image blur can be realized. However, as described in JP-A-1-130144, camera shake is prevented. Since the frequency band of image blur due to the like is considerably low, the signal processing means for processing the output signal of the vibration detection sensor uses a circuit that handles a signal in a band with a low frequency characteristic, so that it takes time to stabilize the output signal. It is necessary to take measures against this. In view of this point, Japanese Patent Application Laid-Open No.
No. 0144 proposes an integrator whose frequency characteristics can be changed by changing the on / off ratio of the switch means which is operated intermittently, and takes this measure. However, since a signal generation circuit such as a triangular wave generator or an absolute value circuit is used for generating a signal for changing the interruption ratio, an increase in cost is inevitable. Further, the values of the resistors and capacitors included in the signal generating circuit vary due to manufacturing errors, and if the frequency characteristics of the signal processing circuit are set to be accurate, the resistors and capacitors are also required to be accurate. You need to use a good and expensive one.

Japanese Patent Application Laid-Open No. Hei 8-136952 proposes that the operation of an integrator or a filter be processed by a digital operation using a microcomputer.
According to this, the change of the frequency characteristic and the like can be performed by the arithmetic processing in the microcomputer without increasing the number of components and circuit elements. However, in order to process the functions of the integrator and the filter by digital operation, a microcomputer that can execute advanced arithmetic processing such as multiply-accumulate operation at a higher speed than a microcomputer that controls general camera mechanisms and the like However, the cost increase was inevitable.

Furthermore, it is often necessary to change the amount of movement of the mechanism for correcting image blur according to the change in the focal length of the photographing lens of the apparatus, and the calculation load on the microcomputer is reduced. As a result, a microcomputer capable of executing arithmetic processing at high speed is required, which has caused an increase in cost.

A first object of the present invention is to change a frequency characteristic of a circuit as desired without using a microcomputer capable of high-speed processing or other expensive electric parts. An object is to provide an optical device having a high-performance image blur correction function.

A second object of the present invention is to provide a high-performance system capable of changing the drive characteristics of the optical axis changing means as desired without using a microcomputer capable of high-speed processing or other expensive electric parts. It is an object of the present invention to provide an optical device having an image blur correction function.

A third object of the present invention is to provide a high-performance high-performance processing apparatus capable of changing the processing characteristics of signal processing means as desired without using a microcomputer capable of high-speed processing or other expensive electric parts. An object is to provide an optical device having an image blur correction function.

[0009]

In order to achieve the first object, according to the present invention, there is provided an angular velocity detecting means for detecting a change in the angle of an optical axis of an optical system as an angular velocity;
Signal processing means for performing signal processing on the output signal of the angular velocity detecting means with predetermined frequency characteristics, optical axis changing means for changing the optical axis, and changing the optical axis according to the output signal of the signal processing means Optical axis change driving means for driving the means,
A microcomputer for controlling various components of the apparatus, wherein the signal processing means is capable of changing its frequency characteristic according to the on / off ratio of the switch means which is operated intermittently; An optical device having a function of outputting a variable continuous pulse signal and having an image blur correction function of supplying the continuous pulse signal as an intermittent operation signal of the switch means.

Conventionally, a signal generating circuit such as a triangular wave generator or an absolute value circuit had to be provided to generate an intermittent operation signal of the switch means. However, according to the above configuration, the microcomputer was already provided. This continuous pulse signal is supplied as an intermittent operation signal of the switch means, and the duty of the continuous pulse signal is changed, for example, when photographing by the photographing means. In accordance with the shutter speed information, and determines the frequency characteristics at the time of signal processing of the angular velocity signal in the vibration processing means.

In order to achieve the second object,
The present invention according to claims 6 to 8 is an angular velocity detecting means for detecting a change in the angle of the optical axis of the optical system as an angular velocity, a signal processing means for performing signal processing on an output signal of the angular velocity detecting means, and changing the optical axis. Optical axis changing means for causing the optical axis changing means to drive the optical axis changing means in accordance with an output signal of the signal processing means, and a microcomputer for controlling various components of the optical device. The optical axis change driving means can change the output magnification of the output signal with respect to the input signal by the intermittent ratio of the intermittently operated switch means, and the microcomputer has a duty-variable continuous pulse signal. And an optical device having an image blur correction function of supplying the continuous pulse signal as an intermittent operation signal of the switch means.

Conventionally, it was necessary to provide a signal generating circuit such as a triangular wave generator or an absolute value circuit for generating an intermittent operation signal of the switch means. Utilizing the duty variable continuous pulse signal output function, and supplying this continuous pulse signal as an intermittent operation signal of the switch means, and, if necessary, changing the duty of the continuous pulse signal by, for example, a focal length changing means. The focal length information of the optical system to be set or the extension position information of the optical system set by the focus detection means is changed in accordance with the output magnification of the output signal with respect to the input signal of the optical axis change driving means. I have.

Further, in order to achieve the third object,
According to a ninth aspect of the present invention, there is provided a vibration detecting means for detecting a vibration applied to the apparatus, a signal processing means for performing signal processing on a detection signal of the vibration detecting means, and the vibration based on an output of the signal processing means. Actuator driving means for driving an actuator acting to prevent an optical effect caused by the microcomputer, and a microcomputer for controlling the device, wherein the signal processing means includes an intermittent operation of the intermittently operated switch means. The microcomputer has a function of outputting a continuous pulse signal of variable duty, and has an image blur correction function of supplying the continuous pulse signal as an intermittent operation signal of the switch means. Optical device.

Conventionally, it was necessary to provide a signal generating circuit such as a triangular wave generator or an absolute value circuit in order to generate an intermittent operation signal of the switch means. This continuous pulse signal is supplied as an intermittent operation signal of the switch means by utilizing the duty variable continuous pulse signal output function to change the circuit characteristics of the signal processing means.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIGS. 1 and 2 are circuit diagrams showing an example of an electric circuit configuration of a camera as an optical device having a function of preventing image blur according to an embodiment of the present invention.
Are respectively connected to 〜 in FIG. 2, and these 〜 are used as terminal names (sometimes signal names).

FIG. 1 shows a component for realizing a function for mainly preventing image blurring in the electrical circuit configuration. Reference numeral 101 denotes a camera for detecting vertical vibration of a camera due to camera shake or the like as an angular velocity. For example, a first vibration detection sensor such as a vibration gyro, 102 is a capacitor, 103 is a variable resistor (to be described in detail later), 104 is an operational amplifier, and an output signal of the vibration detection sensor 101 is variable with the capacitor 102. An operational amplifier 1 in which a DC component is cut by a variable frequency characteristic high-pass filter including a resistor 103 and is connected in a voltage follower connection.
04 is buffer output. 105 is a fixed resistor, 106 is a variable resistor, 107 is a capacitor, 108
Is an operational amplifier, and a circuit section composed of each element from the fixed resistor 105 to the operational amplifier 108 becomes an integrator having a variable frequency characteristic as described in Japanese Patent Application Laid-Open No. 1-130144. . The signal input to the integrator is the angular velocity of the camera shake whose band has been adjusted by the high-pass filter, and by integrating this, the angular displacement of the vibration due to the camera shake or the like is obtained. 109 and 110 are fixed resistors, 111
Is a variable resistor, 112 is an operational amplifier, and a circuit portion composed of each element from the fixed resistor 109 to the operational amplifier 112 is a variable magnification adder, and the output (angular displacement) of the integrator and the output And the signal output from the microcomputer 201 is output at a certain magnification.

Vref applied to one end of the variable resistor 103, the positive input of the operational amplifier 108 and the + input of the operational amplifier 112 is a predetermined reference voltage, and for example, a value of 1/2 of the power supply voltage of the circuit is selected. It is. If +/- bipolar power is supplied to the circuit, the reference voltage Vref becomes 0.
V is fine.

Numeral 113 denotes a driving circuit which outputs a voltage or current proportional to the magnitude of the output signal of the adder to the coil 114.
Turn on electricity. Numeral 120 denotes an optical axis changing means in which the whole or a part of the photographing lens and its supporting member, magnet and the like are integrated.
By moving in the P (pitch) direction, i.e., the vertical direction, the optical axis shift of the captured image due to the detected vertical vibration is canceled out.

Reference numeral 121 denotes a second vibration detecting sensor such as a vibrating gyroscope for detecting the lateral vibration of the camera due to camera shake or the like as angular velocity, 122 denotes a capacitor, 123 denotes a variable resistor, and 124 denotes an operational amplifier. The output signal of the vibration detecting means 121 is cut off the DC component by a variable frequency characteristic high-pass filter comprising the capacitor 122 and the variable resistor 123, and is buffer-output by a so-called voltage follower-connected operational amplifier 124. 125 is a fixed resistor, 126 is a variable resistor, 127 is a capacitor, 128 is an operational amplifier,
A circuit section composed of each element from the fixed resistor 125 to the operational amplifier 128 becomes an integrator having a variable frequency characteristic. The signal input to this integrator is the angular velocity of vibration due to camera shake or the like whose band has been adjusted by the high-pass filter,
This is integrated into an angular displacement of the vibration. Reference numerals 129 and 130 denote fixed resistors, 131 denotes a variable resistor, 132 denotes an operational amplifier.
A circuit section composed of up to 32 elements is a variable magnification adder, and outputs at a certain magnification by adding an output (angular displacement) of the integrator and a signal output by a microcomputer 201 described later. .

The reference voltage Vref applied to one end of the variable resistor 123 and the + inputs of the operational amplifier 128 and the operational amplifier 132 is as described above.

A drive circuit 133 supplies a voltage or current proportional to the magnitude of the output signal of the adder to the coil indicated by 134. The driving circuit 113 or 1
Signals commonly input to the driving circuit 33 are output permission signals of these driving circuits.

The optical axis changing means 120 moves in the Y (yaw) direction, ie, the horizontal direction in FIG. 1 substantially in proportion to the amount of current supplied to the coil 134, so that the optical axis of the photographed image due to the detected horizontal vibration. It works to cancel blur.

The circuit section composed of the adder and the driving circuit in FIG. 1 described above constitutes the optical axis change driving means.

FIG. 2 shows other components of the electric circuit except for the image blur prevention function described with reference to FIG.

Reference numeral 201 denotes a one-chip microcomputer for performing overall control of the camera.
R for storing mainly control programs and fixed data
OM, R for temporarily storing data when performing control or calculation
AM, ALU for executing logical operation, A / D converter for converting analog data input from outside into digital data, so-called duty ratio between high-level section and low-level section at a certain frequency according to data set by software. It has a continuous pulse signal output function that outputs a variably settable continuous pulse signal by hardware. This continuous pulse signal output function may be called a PWM function, a PWM timer, a PPG timer, or the like, depending on slight differences in functions, differences in microcomputer types, and the like. A microcomputer used for controlling an optical device such as a camera usually has a continuous pulse signal output function as described above, and particularly, the cost of the microcomputer greatly depends on the presence or absence of such a function. There is no. The details of the operation sequence of the microcomputer 201 will be described later.

Reference numeral 202 denotes a photometric sensor which includes, for example, a photodiode and an amplifier for amplifying the output of the photodiode, and outputs information on the brightness of the subject as an analog value.
Connected to first input for converter. 203 is configured by, for example, a CCD line sensor or a PSD,
This is a focus detection sensor that outputs information on the focus position of the subject as an analog value, and the output is connected to a second input of the microcomputer 201 for the A / D converter. Reference numeral 204 denotes a battery (not shown) serving as a power supply of the camera.
Is a battery voltage detection circuit that divides or level-shifts the voltage to a predetermined value so as to match the conversion range of the A / D converter, and outputs the divided voltage. Connected to 3 inputs.

Reference numeral 205 denotes a shutter and a driving circuit for opening and closing the shutter in accordance with an output signal from the microcomputer 201 to perform exposure. Reference numeral 206 denotes a first motor drive circuit, which is configured to take a picture indicated by 207 based on a drive signal output from the microcomputer 201 in accordance with information on the focus position of the subject obtained from the output of the focus detection sensor 203. Drive the lens focus adjustment motor. Reference numeral 208 denotes a second motor drive circuit which drives the focal length adjustment motor 209 of the photographing lens based on a drive signal output from the microcomputer 201. Reference numeral 210 denotes a third motor drive circuit, which drives the film winding and rewinding motor 211 based on a driving signal output from the microcomputer 201.

Reference numeral 212 denotes a first stroke switch that is turned on by the first stroke of the release switch, 213 denotes a second stroke switch that is turned on by the second stroke of the release switch, and 214 denotes a switch for changing the focal length of the taking lens. A display unit 215 includes, for example, a liquid crystal device or a light emitting diode, and displays various kinds of photographing information such as the number of photographed images and the date, a warning display, and the like. A strobe device 216 illuminates the subject when the brightness of the subject is insufficient with natural light. A focus detection light source 217 illuminates the subject when the output of the focus detection sensor 203 is insufficient due to, for example, insufficient brightness of the subject when performing focus detection. It is known that there are various methods for focus detection, but depending on the method, such a focus detection light source may always illuminate a subject when performing focus detection.

Numeral 218 denotes a non-volatile memory (EEPROM is assumed in FIG. 2) such as an EEPROM or a ferroelectric memory, and information on manufacturing errors of the filter and the optical axis change driving means shown in FIG. Alternatively, information on the correction value is measured at the time of manufacture and stored. The terminals are the first to eighth output terminals of the above-described continuous pulse signal output function, respectively, and are respectively connected to the terminals in FIG. FIG. 1 shows an intermittent operation signal input terminal of the variable resistor 103, an intermittent operation signal input terminal of the variable resistor 106, an intermittent operation signal input terminal of the variable resistor 111, one terminal of the fixed resistor 110, and a variable The intermittent operation signal input terminal of the resistor 123 is connected to the variable resistor 126
Of the variable resistor 131 is connected to one terminal of the fixed resistor 130. The output terminal of the microcomputer 201 is connected to the output permission terminals of the driving circuits 113 and 133 described above.

Next, an example of the configuration of the variable resistor will be described with reference to FIG.

A variable resistor is provided between terminals T1 and T2.
A fixed resistor R1, a fixed resistor R2, and an analog switch SW which are connected in series are connected in parallel. Further, a terminal for controlling the conduction of the analog switch SW is a terminal T3.

The analog switch SW is turned on when the signal applied to the terminal T3 is at a high level, and is turned off when the signal applied to the terminal T3 is at a low level. If the signal applied to the terminal T3 is at a low level, the analog switch SW is non-conductive,
The resistance value between 1 and T2 becomes the resistance value of the fixed resistor R1 itself, and when the signal applied to the terminal T3 is at a high level, the analog switch SW is conductive. Are fixed resistance R1 and fixed resistance R
2 (R1 ×
R2) / (R1 + R2) ". However, the fixed resistance R1
The continuity resistance value of the analog switch SW is ignored because the resistance value of the analog switch SW is sufficiently small with respect to the resistance values R1 and R2 of the fixed resistor R2.

Considering that the signal supplied to the terminal T3 is a continuous pulse signal which repeatedly changes at a certain time ratio between a high level and a low level as shown in FIG. 4, a period in which the continuous pulse signal is at a high level Inside, terminal T1
The resistance value between T2 and T2 is a combined resistance value when the fixed resistor R1 and the fixed resistor R2 are connected in parallel, "(R1 × R
2) / (R1 + R2) ", and while the continuous pulse signal is at the low level, the resistance value between the terminals T1 and T2 becomes the resistance value of the fixed resistor R1 itself. If the period t of the continuous pulse signal is between the terminals T1 and T2
If the frequency is sufficiently short compared to the frequency of the signal passing between the resistance values, the continuous repetition of this resistance value results in a combined resistance value of “(R
1 × R2) / (R1 + R2) ”and the temporal average value of the resistance value R1.

Therefore, the ratio "ton / t" between the high-level period ton and the period t of the continuous pulse signal applied to the terminal T3 is obtained.
Is plotted on the abscissa and the average resistance between the terminals T1 and T2 is plotted on the ordinate, as shown in FIG. This indicates that the resistance between the terminals T1 and T2 is a variable resistor that changes continuously by continuously changing the so-called duty ratio of the continuous pulse signal applied to the terminal T3. I have. However, in an actual microcomputer, since the duty ratio of the continuous pulse signal is set by digital data, continuous duty is not obtained. For example, if the data for setting the duty ratio of the continuous pulse signal is 8 bits long, 256 steps of duty ratio can be set, and if the data is 16 bits long, 65536 steps of duty ratio can be set.

The so-called cut-off frequency, which is the lower limit frequency of the high-pass filter with variable frequency characteristics composed of the capacitor 102 and the variable resistor 103 and the variable frequency characteristic composed of the capacitor 122 and the variable resistor 123 described in FIG. fc is represented by the following equation, where C is the capacitance value of the capacitor, and R is the resistance value of the variable resistor.

Fc = 1/2 × π × R × C Therefore, the cutoff frequency fc can be varied by changing the resistance value R of the variable resistor. That is, the frequency characteristic of the high-pass filter described with reference to FIG. 1 can be changed.

Here, if the cutoff frequency fc is "0.1
In order to obtain “Hz”, “C = 1.5 μF” is selected, and the duty is set by setting the fixed resistor and the duty of the continuous pulse signal so that “R = 1 MΩ”.

However, since the actual capacitor and resistor have a manufacturing error as described above, the influence of the error is eliminated and the duty of the continuous pulse signal such that the cutoff frequency fc becomes exactly “0.1 Hz” is eliminated. Is output from the microcomputer 201. For example, the nonvolatile memory described above measures the duty of a continuous pulse signal such that the cut-off frequency fc becomes "0.1 Hz" at the time of manufacture in each device. It is stored in the EEPROM 218. If the microcomputer 201 inputs this value from the EEPROM 218 when actually controlling the device, and determines the duty of the continuous pulse signal, a high-pass filter having a cutoff frequency fc of exactly "0.1 Hz" can be constructed. Can be. Note that the value stored in the EEPROM 218 need not be an absolute value, but may be a deviation amount from a standard value.

The fixed resistor 10 described with reference to FIG.
5. The integrator including the variable resistor 106, the capacitor 107, and the operational amplifier 108, and the integrator including the fixed resistor 125, the variable resistor 126, the capacitor 127, and the operational amplifier 128 also have a lower limit frequency at which integration is possible. The cutoff frequency fs is expressed by the following equation, where C is the capacitance value of the capacitor, and R is the resistance value of the variable resistor.

Fs = 1/2 × π × R × C Therefore, the cutoff frequency fs can be made variable by changing the resistance value R of the variable resistor. That is, the integrator described with reference to FIG. 1 can change the frequency characteristic. Further, as in the case of the high-pass filter, the cut-off frequency fs of each device at the time of its manufacture is, for example, “0.1 Hz”.
Measure the duty of the continuous pulse signal so that
The value is stored in the EEPROM 218 described above. If the microcomputer 201 inputs this value from the EEPROM 218 when actually controlling the apparatus and determines the duty of the continuous pulse signal, an integrator having a cutoff frequency fs of "0.1 Hz" can be configured accurately. Can be.

The frequency of the continuous pulse signal output from the microcomputer 201 for changing the frequency characteristics of the high-pass filter and the integrator described above is within the frequency range in which the analog switch SW can respond. The signal passing through the integrator, that is, the signal relating to the vibration of the apparatus due to camera shake or the like must be sufficiently high. Since the signal related to the vibration of the device due to camera shake etc. is a frequency of about several tens Hz at the highest,
The frequency of the continuous pulse signal output from the microcomputer 201 for changing the frequency characteristics of the high-pass filter and the integrator is preferably set to about the order of 10 kHz.

From the fixed resistor 109 in FIG.
An adder composed of up to 12 elements adds the output of the integrator input to the fixed resistor 109 and the continuous pulse signal output from the microcomputer 201 input to the fixed resistor 110. Here, the fixed resistor 10
9 is R109, and the resistance of the fixed resistor 110 is R11.
0, when the resistance value of the variable resistor 111 is R111, the output value of the integrator is Vi, the output value of the continuous pulse signal output from the microcomputer 201 is Vm, and the output value of the adder is Vo, Vo = Vref − (R111 / R109) × (Vi−Vref
)-(R111 / R110) .times. (Vm-Vref). For the sake of simplicity, considering "Vref = 0 V", Vo =-(R111 / R109) .times.Vi- (R111 / R11).
0) × Vm, and the addition ratio of the output Vi of the integrator is determined by the ratio of the resistance values R111 and R109.
Determines the addition magnification of the output value Vm of the continuous pulse signal output. Since the variable resistor 111 is a variable resistor as described with reference to FIGS. 3 to 5, an adder including each element from the fixed resistor 109 to the operational amplifier 112 is a variable magnification adder. You can see that there is.

Since the adder composed of each element from the fixed resistor 129 to the operational amplifier 132 has exactly the same configuration, the addition magnification of the output Vi of the integrator is determined by the ratio between the resistance values R131 and R129. , Resistance values R131 and R
130 is a variable magnification adder in which the addition magnification of the output value Vm of the continuous pulse signal output is determined based on the ratio with respect to 130.

FIG. 6 is a diagram showing a specific example of signal addition by an adder.

Of the signal waveform examples shown in FIG.
1 is a waveform example of the output Vi of the integrator. The vibration frequency of a device caused by camera shake or the like is generally quite low, and is known to be on the order of about "0.1 to 10 Hz". There is no regularity in the amplitude and the like. The signal S2 is a waveform example of the output value Vm of the continuous pulse signal output from the microcomputer, and has a predetermined frequency and a duty of 50%. The signal S3 indicates a result obtained by adding the signal S1 and the signal S2 by the adder, and the signal S3 is compared with the addition magnification of the signal S1.
In order to set the addition magnification to 2 low, the waveform of the signal S2 is superimposed with a small amplitude on the waveform of the signal S1. However, since it is an inversion type adder, the signal S3 is added to the simple addition result of the signal S1 and the signal S2.
Is inverted.

The reason why the continuous pulse signal (waveform example S2) from the microcomputer 201 is superimposed on the integrated output signal (waveform example S1) representing the angular displacement of the vibration of the apparatus due to camera shake or the like will be described.

Since the optical axis changing means 120 described in FIG. 1 is mechanically supported in the apparatus,
When the coil 114 or the coil 134 is moved by being energized, friction occurs with the support member. The frequency band of the vibration of the device due to camera shake etc.
Since it is as low as about 10 Hz, the operating frequency band of the optical axis changing means 120 for canceling the optical axis shake of the captured image due to this is also about 0.1 to 10 Hz. For this reason, the friction accompanying the movement of the optical axis changing means 120 is close to the static friction, and the frictional force is relatively large, and the optical axis changing means 120 cannot move smoothly due to the effect of this frictional force, and the captured image cannot be moved. As a result, the effect of canceling the optical axis blur cannot be sufficiently achieved.

Therefore, in order to reduce such frictional force, apart from the movement for canceling the optical axis blur of the photographed image, the optical axis changing means 120 is driven by a small amplitude within a range that does not affect the photographed image. It is known that the frictional force becomes close to the dynamic friction and the frictional force becomes relatively small. The continuous pulse signal (waveform example S2) from the microcomputer 201 is a signal for performing such small amplitude driving of the optical axis changing means 120. The drive frequency of the minute amplitude drive is determined by the frequency of the continuous pulse signal output from the microcomputer 201, but a frequency that effectively reduces frictional force and does not affect other parts of the apparatus is desirable.

As shown in FIG. 7, the frequency band for preventing the image blurring of the photographed image is approximately "0.1 to 10 Hz" as described above. The drive frequency of the micro-amplitude drive is set to be at least one digit away from the frequency band in which the function of preventing image blur is performed so as not to interfere with the function of preventing image blur. However, on the other hand, a vibration detecting sensor such as a vibrating gyroscope used for detecting image blurring or device blurring often vibrates the sensor portion at a resonance frequency, and generates a vibration close to the resonance frequency. If given from outside the vibration detecting means, the vibration detecting sensor cannot accurately detect the shake of the apparatus. Therefore, it is necessary to set the drive frequency of the minute amplitude drive away from the resonance frequency of the vibration detecting means so that there is no interference.

As an example, as shown in FIG. 7, assuming that the resonance frequency of the vibration detecting sensor is "7 to 8 KHz", the microcomputer 201 sets the drive frequency of the minute amplitude drive to "200 to 300 Hz". If the frequency of the continuous pulse signal is determined, there is no need to interfere with the frequency band that acts to prevent image blur and the resonance frequency band of the vibration detection sensor, and no problem occurs. The addition magnification of the adder also varies due to the manufacturing error of the fixed resistor. Therefore, in each device, the duty of the continuous pulse signal which becomes a predetermined addition magnification at the time of its manufacture is measured, and the value is stored in the EEPROM 218 described above.
To memorize.

If the microcomputer 201 determines the duty of the continuous pulse signal by inputting this value from the EEPROM 218 when actually controlling the apparatus, it forms an adder having a predetermined addition magnification without the influence of an error. can do.

The meaning of the addition magnification of the adder in this circuit configuration will be described.

If the optical axis changing means 120 moves so as to cancel the displacement of the optical axis of the photographed image indicated by the angular displacement signal of the camera shake vibration output from the integrator, and the optical axis is displaced to return the optical axis to the original position. It is possible to prevent blurring of the captured image due to camera shake vibration. However, in general, the displacement amount of the optical axis with respect to the movement amount of the optical axis changing means 120 changes according to the focal length of the photographing lens when the photographing lens is a zoom lens. It is necessary to adjust the drive ratio of the optical axis changing means 120 to the signal.
As a means for adjusting the drive ratio, in the present embodiment, the addition magnification of the adder is adjusted. If the addition magnification of the adder is changed, the output value of the adder changes even if the angular displacement signal of the camera shake vibration output by the integrator changes,
The level of the driving signal output to the driving circuit 113 or 133 changes. Therefore, the amount of current supplied to the coil 114 or 134 also changes, and the amount of movement of the optical axis changing unit 120 also changes. Depending on the configuration type of the photographing lens, it may be necessary to adjust the drive ratio of the optical axis changing means 120 to the angular displacement signal of camera shake depending on the amount of extension of the lens for focus adjustment. In this case, the addition magnification of the adder is set based on both the focal length information of the lens and the extension amount of the lens (photographing distance information).

The overall flow of the operation sequence of the microcomputer 201 will be described with reference to the timing chart of FIG.

When a main switch (not shown) is turned on,
The power is turned on to the electric circuit, and the period becomes t1 in the figure.
A sensor (vibration detection sensor) for detecting image blur requires a certain amount of time from when the power is turned on until the output becomes stable. Therefore, a high-pass filter or an integrator that receives the unstable output has a low cut-off frequency fc or fs. The output is easily saturated. Accordingly, the microcomputer 201 outputs an output signal with one of the continuous pulse output terminals at the maximum duty so that the cut-off frequency fc of the high-pass filter becomes the maximum, and sets the cut-off frequency fs of the integrator to the maximum. The microcomputer 201 outputs an output signal from one of the continuous pulse output terminals at the maximum duty. At this timing, the vibration is not yet detected and the operation for preventing image blur due to the vibration is not performed. Therefore, the cutoff frequency fc or fs may be higher than the cutoff frequency when the operation for preventing image blur is performed.

In the continuous pulse output function, once the output data is set, the same waveform is repeatedly output by the hardware thereafter, so that the microcomputer 201 does not need to change the duty or the like unless it is necessary to change the duty or the like. , Other processing can be performed. That is, the load on the microcomputer 201 for driving the optical axis changing means with a small amplitude can be reduced.

Further, a signal is output to the second motor drive circuit 208 so as to move the photographing lens to the initial position as needed during the period of t1, and the focal length adjusting motor of the photographing lens is driven. . When these sequences are completed, the process moves to the period t2. Microcomputer 2
01 charges the strobe device 216 so as to be able to emit light. When the charging is completed, the process moves to a period of t3.

When the time required for the output of the vibration detection sensor to stabilize elapses, the microcomputer 201 sets the cut-off frequency of the high-pass filter or the integrator to the original cut-off frequency required for vibration detection. Change the duty of the output signal. The output signal from one of the continuous pulse output terminals is changed from the maximum duty to a predetermined duty so that the cutoff frequency fc of the high-pass filter becomes a predetermined value. In this case, as described above, the cutoff due to a manufacturing error of the circuit element is performed. The duty of the continuous pulse signal is determined with reference to a value stored in the EEPROM 218 in advance so that an error of the frequency fc does not occur.

Similarly, the output signal with one of the continuous pulse output terminals is changed from the maximum duty to a predetermined duty so that the cut-off frequency fs of the integrator also becomes a predetermined value. In order to prevent the error of the cutoff frequency fs from occurring due to the manufacturing error of the element,
The duty of the continuous pulse signal is determined with reference to the value stored in M218.

When the sequence of changing the cutoff frequency is completed, the process moves to the period of t4. If the focal length changing switch 214 of the photographing lens is operated during this period, the microcomputer 201 changes the focal length of the photographing lens in accordance with the operation of the switch. To drive the focal length adjusting motor 209 of the photographing lens. This allows the photographer to select a preferred focal length.

When it is detected that the first stroke switch 212 is turned on, the process proceeds to a period of t5. During this period, the microcomputer 201 first performs focus detection as preparation for photographing. Focus detection light source 217 if necessary
Is emitted to illuminate the subject, and the output information of the focus detection sensor 203 is read while performing A / D conversion. Further, the read information is arithmetically processed to obtain information on the focal position of the subject, and the obtained information is used as lens drive information for focusing.
Further, a signal is output to the first motor drive circuit circuit 206 in accordance with the obtained drive information to drive the focus adjustment motor 207 of the photographing lens to bring the photographing lens into a focused state. At this time, the extension position of the photographing lens can be obtained from information of an encoder or the like (not shown), and information about the photographing distance of the subject can be obtained. Subsequently, by reading the output signal of the photometric sensor 202 while performing A / D conversion, information on the brightness of the subject is obtained, and based on this information, information on a shutter speed and an aperture value for achieving proper exposure is calculated. .

When the sequence of the focus detection and the photometry is completed, the process moves to a period of t6. During this period, the microcomputer 201 changes the cutoff frequency of the high-pass filter or the integrator and sets the addition magnification of the adder.

First, the cut-off frequency f of the high-pass filter is determined based on the shutter speed information obtained during the period t5.
c and the cutoff frequency fs of the integrator are changed. This means that, for example, when a shutter speed is relatively high, it is not meaningful to select a low cut-off frequency that prevents low-frequency camera shake vibration, and also, it is possible to prevent vibration due to poor response of the circuit. This is because the error increases. Therefore, if the shutter speed is high, the cutoff frequency fc of the high-pass filter and the cutoff frequency fs of the integrator are set on the high frequency side, respectively, and if the shutter speed is low, the cutoff frequency fc of the high-pass filter and the cutoff of the integrator are set. The duty of the output signal of the continuous pulse output terminal is changed so that the frequency fs is set to the low frequency side. At the time of setting, the data stored in the EEPROM 218 at the time of manufacture is referred to by the above-described method so that an error in cutoff frequency due to a manufacturing error is not generated.

Next, the addition magnification of the adder is determined based on the focal length information of the photographing lens set in the period of t4 and the information on the photographing distance of the subject obtained in the period of t5. At this stage, only the addition magnification of the adder is determined, the continuous pulse signal is not yet output to the output terminal or to the output terminal, and the output of the drive circuits 113 and 133 is not permitted.

When the ON of the second stroke switch 213 is detected, the process moves to the period of t7. Microcomputer 2
01 starts output of the continuous pulse signal to or from the output terminal to operate the adder at the addition magnification determined in the period of t6, and the continuous pulse for micro drive vibration for reducing the frictional force. It also outputs a signal. Further, by permitting the driving of the driving circuits 113 and 133 by a signal, the energization of the coils 114 and 134 is also started. As a result, the movement of the optical axis changing means 120 for preventing camera shake vibration is started, and the preparation for photographing is completed. It moves to the period of t8.

The microcomputer 201 outputs a signal to the shutter drive circuit 205 based on the shutter speed and the aperture value obtained during the period t5 to open and close the shutter to perform exposure. The optical axis changing means 12 has already started from the period of t7.
Since the movement of 0 has started, the action of preventing the optical axis from being changed due to camera shake is performed even during this period, and a high-quality image without image blur is captured.

When the opening and closing of the shutter is completed, a period of t9 is started.

The microcomputer 201 inhibits the driving of the driving circuits 113 and 133 by a signal, thereby stopping the energization of the coils 114 and 134. Further, the output of the continuous pulse signal to the output terminal and / or the output terminal is stopped to set the addition magnification of the adder to an initial state, and the continuous pulse signal for micro drive vibration for reducing frictional force is also stopped. This stops the movement of the optical axis changing means 120 for preventing camera shake vibration. Subsequently, a period of t10 is set.

The microcomputer 201 outputs a signal to the third motor driving circuit 210 to drive the film winding and rewinding motor 211 to wind up the film. At this time, the output signals of the vibration detection sensors 101 and 121 may become unstable due to vibration or the like caused by winding, and a high-pass filter or an integrator receiving the unstable output also has a low cutoff frequency fc or fs. And the output is likely to be saturated. Therefore, the microcomputer 201 changes the output signal with the continuous pulse output terminal to output at the maximum duty so that the cutoff frequency fc of the high-pass filter becomes the maximum, and the cutoff frequency fs of the integrator becomes the maximum. The microcomputer 201 changes the output signal from the continuous pulse output terminal to the output signal with the maximum duty. When the film winding operation is completed, t
It moves to period 11.

Although the photographing sequence has been completed, the first stroke switch 21 of the release switch
2 or the second stroke switch 213 is continuously turned on, the cut-off frequency fc or fs of the high-pass filter or the integrator is set to t in preparation for photographing of the next photographing frame.
The microcomputer 201 changes the output signal with the continuous pulse output terminal from the maximum duty so as to return to the one set in the period of 6, and the microcomputer 201 operates so that the cutoff frequency fs of the integrator becomes maximum. The output signal from the continuous pulse output terminal is changed from the maximum duty ratio. However, when the first stroke switch 212 or the second stroke switch 213 of the release switch is released and the main switch is also turned off, the sequence ends.

Although not described in the sequence described above, as described in the above-mentioned Japanese Patent Application Laid-Open No. 1-130144, when the output of the integrator is saturated, the output of the integrator becomes saturated as soon as possible. It is also possible to cause the microcomputer 201 to perform an operation of changing the cut-off frequency fs of the integrator to a higher value so as to bring it into a steady state. In this case, the microcomputer 201 needs to know whether or not the output of the integrator is within a predetermined range.
Also connected to the / D converter input terminal. The microcomputer 201 inputs and outputs the output of the integrator by A / D conversion in a predetermined cycle during a period from t3 to t11 in which the integrator functions, and the obtained data exceeds a predetermined range. Can be considered assuming that the output of the integrator is saturated and changing the output signal duty with the continuous pulse output terminal so that the cut-off frequency fs of the integrator becomes the maximum value for a required time. .

(Modification) In the above embodiment, an example is described in which the present invention is applied to a camera such as a single-lens reflex camera. However, optical devices and other devices other than the camera, and furthermore, those cameras, optical devices and other devices The present invention can be applied to a device applied to the present invention or an element constituting the device.

[0074]

As described above, according to the present invention, the frequency characteristics of a circuit can be changed as desired without using a microcomputer capable of high-speed processing or other expensive electric parts. It is possible to provide an optical device having a high-performance image blur correction function.

Further, according to the present invention, it is possible to change the drive characteristics of the optical axis changing means as desired without using a microcomputer capable of high-speed processing or other expensive electric parts. An optical device having an image blur correction function can be provided.

Further, according to the present invention, a high-performance image processing apparatus capable of changing the processing characteristics of the signal processing means as desired without using a microcomputer capable of high-speed processing or other expensive electric parts. An optical device having a blur correction function can be provided.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a part of a configuration of an optical device having an image blur correction function according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing another portion of the configuration of the camera having the image blur correction function according to one embodiment of the present invention.

FIG. 3 is a circuit diagram illustrating a configuration example of a variable resistor illustrated in FIG. 1;

FIG. 4 is a diagram showing a waveform example of a continuous pulse signal output from the microcomputer of FIG. 2;

FIG. 5 is a diagram illustrating a change in the resistance value of the variable resistor shown in FIG.

FIG. 6 is a diagram illustrating waveform addition by the adder shown in FIG. 1;

FIG. 7 is a diagram illustrating a signal band according to an embodiment of the present invention.

FIG. 8 is a timing chart showing a series of operations of a camera having an image blur correction function according to an embodiment of the present invention.

[Explanation of symbols]

 101, 121 Vibration detection sensor 103, 106, 111 Variable resistor 123, 126, 131 Variable resistor 113, 133 Drive circuit 120 Optical axis changing means 201 Microcomputer

Claims (9)

[Claims] 1. An angular velocity detecting means for detecting a change in the angle of an optical axis of an optical system as an angular velocity, a signal processing means for performing signal processing on an output signal of the angular velocity detecting means with a predetermined frequency characteristic, Optical axis changing means for causing the optical axis changing means to drive the optical axis changing means in accordance with an output signal of the signal processing means, and a microcomputer for controlling various components of the apparatus. The signal processing means can change the frequency characteristic of the switch means by the on / off operation of the switch means, and the microcomputer has a function of outputting a continuous pulse signal with a variable duty; An optical device having an image blur correction function, wherein a signal is supplied as an intermittent operation signal of the switch means. 2. The signal processing device according to claim 1, wherein the signal processing means has at least one of a filter circuit and an integrator whose frequency characteristics change according to the on / off ratio of the switching means that is operated on and off. An optical device having an image blur correction function. 3. The microcomputer according to claim 2, wherein the microcomputer changes a duty of the continuous pulse signal supplied as an intermittent operation signal of the switch means in accordance with a sequence for controlling various components of the apparatus. Item 2. An optical device having an image blur correction function according to Item 1. 4. The microcomputer according to claim 1, wherein the microcomputer changes a duty of the continuous pulse signal supplied as an intermittent operation signal of the switch means in accordance with shutter speed information at the time of photographing by the photographing means. An optical device having an image blur correction function according to the above. 5. A storage device for storing information relating to a manufacturing error of the signal processing device, wherein the microcomputer generates an intermittent operation signal of the switch device based on the information stored in the storage device. 3. The optical device having an image blur correction function according to claim 1, wherein the duty of the continuous pulse signal to be supplied is changed. 6. An angular velocity detecting means for detecting a change in the angle of the optical axis of the optical system as an angular velocity, a signal processing means for performing signal processing on an output signal of the angular velocity detecting means, and an optical axis change for changing the optical axis. Means, an optical axis changing drive means for driving the optical axis changing means in accordance with an output signal of the signal processing means, and a microcomputer for controlling various components of the optical device. The axis change driving means is capable of changing the output magnification of an output signal with respect to the input signal by the intermittent ratio of the intermittently operated switch means. The microcomputer has a function of outputting a continuous pulse signal of variable duty. An optical device having an image blur correction function, wherein the continuous pulse signal is supplied as an intermittent operation signal of the switch means. 7. The microcomputer according to claim 1, wherein the microcomputer changes the continuous pulse signal according to focal length information of the optical system set by a focal length changing unit or extension position information of the optical system set by a focus detecting unit. 7. The optical device having an image blur correction function according to claim 6, wherein the optical device is supplied as an intermittent operation signal. 8. A storage unit for storing information relating to a manufacturing error of the optical axis change driving unit, wherein the microcomputer converts the continuous pulse signal based on the information stored in the storage unit. 7. An optical device having an image blur correction function according to claim 6, wherein the optical device is supplied as an intermittent operation signal of a switch means. 9. A vibration detecting means for detecting a vibration applied to the apparatus, a signal processing means for processing a detection signal of the vibration detecting means, and an optical influence of the vibration based on an output of the signal processing means. Actuator control means for driving an actuator that acts to prevent the occurrence of a signal, and a microcomputer for controlling the device. Wherein the microcomputer has a function of outputting a continuous pulse signal with a variable duty, and supplies the continuous pulse signal as an intermittent operation signal of the switch means. An optical device having: