JP2002268111A - Electronic equipment and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the oscillation of an object to be detected from being erroneously detected because of the oscillation of parts other than the object to be detected. SOLUTION: The electronic equipment is provided with a driving source for driving an actuator and an oscillation gyro having frequency characteristic including detuning frequency X (Hz), and oscillation frequency Z' (Hz) generated corresponding to the driving of the driving source being the part other than the object to be detected in terms of oscillation in the electronic equipment is set to a frequency band where the detuning frequency of the oscillation gyro is avoided by specified frequency or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in electronic equipment and cameras using a vibrating gyroscope.

[0002]

2. Description of the Related Art In recent years, many electronic devices have a function of detecting vibration using a vibration detection sensor. Above all, in an optical electronic device such as a camera and a video camera, in order to reduce a low-frequency (for example, about 1 to 10 Hz) blur caused by a user performing a shooting (recording) operation by hand, that is, a so-called “camera shake”. Amplifies the output (angular velocity signal) of the vibration gyro, which is a vibration detection sensor, converts it into an angle signal via an integration circuit, and drives a part of the photographing optical system (correction optical system) based on the angle signal. There are many systems that adopt a method of reducing blur on an imaging medium such as a film or a CCD.

Some of the vibrating gyroscopes use a quartz vibrator. The vibrating gyroscope of the quartz vibrator type uses a tuning fork vibrator at a predetermined driving frequency (several tens of k).
(Hz), the Coriolis force generated by external vibration is detected as angular velocity.

Since the vibrating gyroscope uses a quartz vibrator, detuning (for example, several hundred Hz) occurs, and the vibration detection sensitivity becomes higher than the normal range around the detuning frequency X (Hz). (See FIG. 2).

[0005] When used in the electronic equipment having a shake detection function, since the vibration to be detected is a camera shake, it is sufficient to detect a vibration at a frequency of several Hz. Although not a detection target, the electronic device has a drive source such as an optical focus adjustment motor, and the vibration frequency generated by driving the motor may coincide with the detuning frequency of the vibration gyro. When the vibration frequency and the separation frequency match or become very close to each other, the detection sensitivity of the vibration gyro is high,
If a large angular velocity signal is output and exceeds the dynamic range of the detection circuit, it may be combined with the signal of the "camera shake" correction target and perform erroneous correction drive in spite of the vibration not being detected. is there.

FIG. 8 shows an example of the difference between the detection signal of the vibration gyro and the movement of the correction optical system depending on the presence or absence of the influence of the driving source.

FIG. 8A shows the output of a vibrating gyroscope when a low-frequency vibration equivalent to a camera shake (for example, a 5 Hz sine wave) is given. FIG. 8B shows the vibration in addition to FIG. FIGS. 8C and 8D show the output of the vibration gyro when a high-frequency vibration (for example, 300 Hz) smaller than the low-frequency vibration from the drive source corresponding to the detuning frequency of the gyro is applied.
FIG. 9 shows a drive current of the correction optical system generated based on the output of the vibrating gyroscope shown in FIGS.

As can be seen from FIGS. 8 (a) and 8 (c), the correction optical system can be properly driven in the case of only low-frequency shake to be corrected. However, as shown in FIG. When a vibration from the source is applied, the signal is recognized as a large signal due to a difference in the amplification degree despite the slight vibration.

Even when high-frequency vibration (vibration caused by a driving source) is applied as a large signal, the correction optical system is mechanically difficult to follow high-frequency.

However, the large signal causes the waveform to exceed the dynamic range (Vmax) of the detection circuit. As a result, the desired control which is affected by the offset and the gain affects the drive current of the correction optical system. Different correction driving will be performed.

(Object of the Invention) A first object of the present invention is to provide an electronic device capable of preventing erroneous detection of a vibration to be detected due to a vibration outside the detection target.

A second object of the present invention is to provide a camera capable of preventing erroneous detection of camera shake caused by vibration other than camera shake.

[0013]

According to a first aspect of the present invention, a driving source for driving an actuator and a vibrating gyroscope having a frequency characteristic including a detuning frequency are provided. An electronic device that sets a vibration frequency generated in response to driving of the drive source that is not a vibration detection target in the electronic device in a frequency band that avoids a detuning frequency of the vibration gyro by a predetermined frequency or more. It is assumed that.

[0014] Similarly, in order to achieve the first object,
According to a third aspect of the present invention, there is provided a vibration gyro, a shake detecting means for detecting a shake in a predetermined frequency band having a frequency characteristic including a detuning frequency, and driving at a frequency different from the detection frequency of the shake detecting means. An electronic device having a driving source for driving an actuator, wherein the vibration frequency generated in response to the driving of the driving source is set so as to avoid a predetermined frequency or more from the detuning frequency of the shake detecting means. It is.

Further, in order to achieve the second object,
According to a seventh aspect of the present invention, there is provided a vibration gyro, a vibration detecting means for detecting a vibration in a predetermined frequency band having a certain frequency characteristic of a detuning frequency, and driving at a frequency different from the detection frequency of the vibration detecting means. A vibration frequency generated in response to the driving of the motor is set so as to avoid a predetermined frequency or more from the detuning frequency of the shake detecting means.

[0016]

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

(First Embodiment) FIG. 1 is a perspective view showing a schematic configuration of a camera system which is an electronic apparatus with a shake detecting function according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a switch SW1 for instructing to start capturing information and a switch S for instructing to start exposure.
A two-stage switch for turning on W2, a distance measuring device (AF) 2 for performing a well-known distance measuring operation when the switch SW1 is turned on, and a known light measuring device for when the switch SW1 is turned on A photometric device (AE) 4 that performs an operation is a known photographing optical system (Lens), and a part of the photographing optical system 4 includes a correction optical system (Shift) 5 for blur correction, a shutter (not shown), and the like. Contains.

Reference numeral 6 denotes a motor (M) for moving the photographing optical system 4 in accordance with the result of distance measurement by the distance measuring device 2 and performing optical focus adjustment. 7 Attached to the camera body for detecting lateral movement of the camera. Vibration gyro (Gyro-Y),
Numeral 8 denotes a vibrating gyro (Gyro-P) attached to the camera body for detecting vertical camera shake.

The vibrating gyroscope 7 and the vibrating gyroscope 8
Are set to different frequencies (for example, 27 kHz and 29 kHz) in order to prevent interference. The detuning frequency of the vibrating gyroscopes 7 and 8 is X (Hz) (for example, 300 (Hz)) as shown in FIG.
And the gain at the detuning frequency is Y (d
B) (for example, 20 (dB) = 10 times).
(In this embodiment, for convenience of explanation, it is assumed that the vibrating gyroscopes 7 and 8 have similar frequency characteristics.)
FIG. 3 is a schematic control block diagram of a camera system which is an electronic device with a shake detection function according to the first embodiment of the present invention, and the same parts as those in FIG. 1 are denoted by the same reference numerals.

In FIG. 1, reference numeral 10 denotes a control circuit for controlling the camera system. Reference numeral 11 denotes a battery serving as a basic power supply of the camera system, 12 denotes a shutter (SH) provided in a part of the photographing optical system 4, 13 denotes a lens barrel control circuit for controlling the motor 6, and 14 denotes a vibration gyro 7. An integrating circuit for converting an output signal (angular velocity output) of the vibrating gyroscope 8 into angular displacement;
And a shake correction control device for driving the correction optical system 5 in the shake correction direction based on the shake information obtained by the integration circuit 14.

The vibrating gyros 7, 8 and the integrating circuit 14
These constitute the shake detecting means in the present embodiment.

FIG. 4 is a flowchart showing the operation of the control circuit 10 of the camera system having the above configuration. The operation starts when the switch SW1 is turned on.

First, in step # 100, the remaining voltage of the battery 11 is checked by an A / D converter (not shown) built in the control circuit 10. Then, in the next step # 101, the vibration gyro (Gyro-Y)
7. Power is supplied to the vibrating gyroscope (Gyro-P) 8, and the vibrating gyroscope 8 is turned on. Next, in step # 102, a well-known photometric operation by the photometric device (AE) 3 is performed. In the following step # 103, a well-known distance measuring operation by the distance measuring device (AF) 2 is performed. Based on the photometry information and the distance measurement information obtained in step # 102 and step # 103, an arithmetic operation for determining the focus adjustment position and exposure time (opening time of the shutter (SH) 12) of the photographing optical system 4 is performed. Do.

In the next step # 105, it is determined whether or not the switch SW2 has been turned on. If the switch SW2 has not been turned on, the process proceeds to step # 106.
It is determined whether or not 1 has been turned off. If it has not been turned off, the process returns to step # 105. On the other hand, if it has been turned off, the present sequence ends, and the system enters a standby state for the next operation.

At step # 105, the switch SW2
Is ON, the process proceeds to step # 107, and the integration circuit 1
4 is driven, and the control circuit 10 receives the output signals (angular velocity signals) of the vibrating gyroscopes 7 and 8 which have already been operated as signals converted into angular displacement. Then, the next step # 108
, The blur correction controller 15 is controlled based on the integration result started in step # 107, and the correction optical system (S
hift) 5 is started. (Drive control of the correction optical system 5 is continued based on the output of the integration circuit 14 from step # 108 to step # 117.) The next steps # 109 to # 111 are the lens barrel control circuit 13.
Is used to rotate the motor 6, which is the driving source, to move the photographing optical system 4 to the focus adjustment position obtained in step # 104. Steps # 109 to # 11
In step 1, the energization of the motor 6 is duty-controlled so as to have a constant voltage in accordance with the remaining amount of the battery 11 confirmed in step # 100.

FIG. 5 shows a change in the rotation speed of the motor 6 due to the above-mentioned energizing operation, and FFT (Fast Fourier Transforrn
(Fast Fourier Transform)) Waveform and Vibration Gyro 7, 8
6 are shown in FIG.

The speed gradually increases from the start of energization, and Z (rpm) (for example, 12000 (rpm)) in a stable region.
(= Z ′ (Hz) (for example, 200 (Hz))).
Frequency (vibration frequency) corresponding to the rotation speed of the motor 6
Z ′ (Hz) and the detuning frequency X (H
The relationship of z) is “X> Z ′” (for example, 300 Hz> 200 Hz) as shown in FIG. Note that Z ′ (Hz) is changed from X (Hz) to a predetermined frequency d (Hz) (for example, 50) so that a desired gain (gain close to a steady state) is obtained based on the frequency characteristics of the vibrating gyroscope.
(Hz)).

In steps # 112 to # 114, the shutter 12 is opened and closed (film exposure control) based on the exposure time obtained in step # 104.
Then, in step # 115, the vibration gyro 7,
8 and stop the operation of the integration circuit 14, and in the next step # 116, control the lens barrel control circuit 13,
The photographing optical system 4 is returned to the initial position. Subsequent step # 117
In, the blur correction controller 15 is controlled, and the driving of the correction optical system 5 is stopped. Finally, in step # 118, feeding of one film is performed by a feeding device (not shown), and the apparatus enters a standby state for the next operation.

According to the first embodiment described above, the motor has the vibrating gyroscopes 7 and 8 having a frequency characteristic having a detuning frequency, and the vibration gyroscopes 7 and 8 are not subject to vibration detection (camera shake). 6 is set to a frequency band in which the detuning frequency of the vibrating gyroscopes 7 and 8 is avoided by a predetermined frequency or more. Detection could be prevented.

In the first embodiment, the vibration frequency that affects the vibration gyro corresponding to the driving of the driving source (motor) is the rotation speed (rotation frequency) of the motor. However, the present invention is not limited to this. However, for example, the case where the vibration frequency is the rotation frequency of the gear synchronized with the rotation of the motor is also included.

The relationship between the vibration frequency Z 'and the detuning frequency X (Hz) of the vibration gyro does not matter even if "X <Z'". In this case, the amount of vibration of the housing that vibrates at the same vibration frequency increases, and as shown in this embodiment, the driving frequency of the driving source is lower than the detuning frequency of the vibration gyro. Frequency band ("X> Z '")
It is preferable to set

Further, the drive source (motor) of the first embodiment is a constant voltage drive by duty control. However, even when the drive source is directly driven by a battery voltage, the vibration frequency and the detuning frequency are separated by a predetermined value or more. If there is no problem.

(Second Embodiment) In the first embodiment, the rotation frequency of the motor is set as the vibration frequency generated by the driving of the drive source, and the rotation frequency and the detuning frequency of the vibration gyro are specified. Shifted by frequency (avoided)
Although the configuration is adopted, the vibration frequency is actually affected by harmonics accompanying the rotation frequency.

In the second embodiment of the present invention, in view of the above problem, the rotational frequency (vibration frequency) Z '(Hz) of the drive source is used.
And Z2 'which is the second harmonic and third harmonic of Z'
(Hz), harmonic generation frequencies such as Z3 '(Hz) are set so as to avoid the detuning frequency X (Hz).

FIG. 7 shows an FFT analysis waveform of the vibration of the vibration gyro-attached housing (camera body) when the driving source (motor) is driven according to the second embodiment of the present invention, and a frequency characteristic of the vibration gyro. It is.

As can be seen from FIG.
The sensitivity becomes maximum at the detuning frequency X (Hz) (for example, 300 (Hz)).

Then, the driving source (motor) is controlled so that the rotation frequency Z '(Hz) does not coincide with X (Hz), and
The number of rotations (for example, 14400 (rpm) (Z '= 240 (H)) at which the second harmonic Z2' (Hz) and the third harmonic Z3 '(Hz) of the rotation frequency Z' do not coincide with X (Hz).
z), Z2 '= 480 (Hz), Z3' = 720 (H
z))) are set.

The detuning frequency X (Hz) and the harmonic Z
It is also assumed that the difference between 2 'and Z3' is also separated by a predetermined frequency d (Hz) or more. (However, since the sensitivity changes depending on the frequency characteristics of the vibrating gyroscope, the predetermined frequency d (Hz) does not need to be uniform between the case of the rotation frequency Z 'and the case of Z2' and Z3 ', etc.) According to the second embodiment, the rotation frequency (vibration frequency) Z '(H
z) and Z which is the second and third harmonic of Z ′
By setting the harmonic generation frequencies such as 2 '(Hz) and Z3' (Hz) so as to avoid the detuning frequency X (Hz), the vibration gyro can erroneously detect vibrations due to vibrations outside the detection target. The frequency can be reduced.

In the above embodiment, the detuning frequency is set between the vibration frequency and the harmonic generation frequency.
The present invention is not limited to this. For example, the detuning frequency is set between the second harmonic and the third harmonic (Z ′ <Z2 ′ <X
<Z3 ′) or setting the detuning frequency higher than the third harmonic (Z ′ <Z2 ′ <Z3 ′ <X) does not mean that there is no problem.

In addition, although the above embodiments have been described using an electronic device such as a camera, the present invention is not limited to this. For example, even in the case of a vibration detecting device used for an automobile or the like, It doesn't matter at all.

[0042]

As described above, according to the first or third aspect of the present invention, it is possible to provide an electronic apparatus capable of preventing erroneous detection of a vibration to be detected due to a vibration that is not to be detected.

According to the seventh aspect of the present invention, it is possible to provide a camera capable of preventing erroneous detection of the camera shake due to vibration other than camera shake.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a camera system according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a frequency characteristic of the vibration gyro in FIG. 1;

FIG. 3 is a block diagram illustrating an electrical configuration of the camera system according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing a series of operations of the camera system according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a change in rotation speed when a motor is driven in the first embodiment of the present invention.

6 is a diagram showing a frequency characteristic of the vibration gyro of FIG. 1 and a waveform of a camera body vibration FFT analysis.

FIG. 7 is a diagram illustrating a frequency characteristic of a vibration gyro and a camera body vibration FFT analysis waveform according to the second embodiment of the present invention.

FIG. 8 is a diagram illustrating an example of a detection signal of a general vibration gyro and a difference between movements of a correction optical system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switch 2 Distance measuring device 3 Photometric device 4 Photographing optical system 5 Correction optical system 6 Motor (for optical focus adjustment) 7 Vibrating gyro (for detecting horizontal shake) 8 Vibrating gyro (for detecting vertical shake) 10 Control circuit 13 Lens barrel drive Circuit 14 Integrator 15 Shake correction controller

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/232 H04N 5/232 Z F-term (Reference) 2F105 AA02 AA08 BB04 CC01 CD02 CD06 2H044 DA01 DB02 DC02 DC10 5C022 AB55 AC54 AC69 AC74

Claims (7)

[Claims] 1. An electronic device having a drive source for driving an actuator and a vibration gyro having frequency characteristics including a detuning frequency, wherein the electronic device has a drive source that is not subject to vibration detection. An electronic device, wherein the generated vibration frequency is set to a frequency band that avoids a detuning frequency of the vibration gyro by a predetermined frequency or more. 2. The electronic device according to claim 1, wherein the drive source is a motor, and the vibration frequency corresponds to a rotation speed of the motor. 3. A vibration detecting means having a vibration gyro and detecting a vibration in a predetermined frequency band having a frequency characteristic including a detuning frequency, and an actuator driving means for driving at a frequency different from the detection frequency of the vibration detecting means. An electronic device comprising: a driving source, wherein a vibration frequency generated in response to driving of the driving source is set so as to avoid a predetermined frequency or more from a detuning frequency of the shake detecting means. 4. The apparatus according to claim 3, wherein said drive source is an optical focus adjusting motor, and said vibration frequency is a frequency corresponding to a rotation speed of said optical focus adjusting motor.
An electronic device according to claim 1. 5. The electronic device according to claim 1, wherein the vibration frequency is set so as to shift to a frequency band lower than the detuning frequency. 6. The electronic device according to claim 1, wherein the detuning frequency is also deviated from the vibration frequency and a harmonic generation frequency of the vibration frequency. 7. A vibration detecting device, comprising: a vibration gyro, for detecting a vibration in a predetermined frequency band having a frequency characteristic of a detuning frequency; and a motor driven at a frequency different from the detection frequency of the vibration detecting device. A camera having a camera, wherein a vibration frequency generated in response to driving of the motor is set so as to avoid a predetermined frequency or more from a detuning frequency of the shake detecting means.