JPS61191171A - Photographing device - Google Patents

Abstract

PURPOSE:To suppress picture blur even if an inexpensive oscillating gyroscope is used, by detecting the shock applied to a photographing means and cutting off the output of an angular velocity detecting means for a prescribed time if the shock exceeds a prescribed value. CONSTITUTION:If such shock is applied to an optical system 107, an image pickup device 108, and a gyroscope 103 of a photographing device 100 that the output of the gyroscope is abnormal, an output 110 of a shock detecting sensor 101 is changed immediately. An output 111 of an angular velocity detecting circuit 104 is changed also after a while. When the signal 110 is increased to reach a set value er, a switch circuit 102 cuts off the output of the circuit 104 immediately. Though the shock is attenuated with time and the signal 110 is reduced, the device 103 and the circuit 104 cause transient phenomena and continue to output abnormal outputs. The circuit 102 connects the output of the circuit 104 to a picture rocking suppressing signal generating circuit 105 again after transient phenomena are terminated and outputs are settled, and an optical axis compensating mirror 106 is controlled by the output of the circuit 105 to compensate the picture blur.

Description

DETAILED DESCRIPTION OF THE INVENTION This field of industrial application relates to photographing devices such as video cameras used in combination with recording devices such as video tape recorders.

Conventional Technology In recent years, photographic devices have been made lighter and smaller, and automated such as automatic exposure and automatic focusing, with the aim of improving their mobility and operability. These technologies have made it possible for non-experts to record high-quality video. However, when considering the quality of recorded images, it is clear that the presence or absence of image blur affects the quality of the image, as well as whether the image is properly exposed, whether it is in focus, and whether it is in focus.

Conventionally, methods for suppressing the above-mentioned image blur include fixing the photographing device to the ground on which the subject is standing using a tripod, or fixing the photographing device to the ground without fixing it to the ground. A gyroscope, etc. is installed inside the device to detect the attitude of the photographic bag/placement relative to the ground. is proposed.

Although the former method is widely used, it is clear that it significantly impairs the mobility of the imaging device and goes against the aforementioned technological trend.

An example of the latter photographing device will be described below with reference to the drawings. For the sake of simplicity, it is assumed that only the pitching (vertical shaking) of the image shaking is corrected. FIG. 4 shows the configuration of a conventional photographing device. In Figure 4, 40
Reference numeral 1 denotes a gyro device that detects the rotation of the photographing device around an axis perpendicular to the paper surface. Its structure is as shown in FIG. 5, with a gyro rotor 501 supported by gimbal mechanisms 502 and 503, which itself rotates at a rotation speed of about 10,000 revolutions per minute. Therefore, the gyroscopic effect of the gyro rotor 501 always keeps the camera pointing in a fixed direction, so when the attitude of the photographing device 400 to which it is attached changes, the photographing device You can know 400 postures.

In FIG. 4, 402 is an optical axis correction signal generation circuit;
3 is a mirror for optical axis correction, which rotates around an axis perpendicular to the plane of the paper. 406 is an imaging device for performing photoelectric conversion and extracting electrical image information, and 405 is an optical system for forming an image on the imaging device 406.

The operation of the photographing device 400 configured as described above will be described below. When the photographic device 400 is stationary, the light emitted from the subject is transmitted through the optical system 405.
After being reflected by a mirror 403 on the way, it enters the optical system 4 again.
05, and an image is formed on the imaging device 406.

Next, when an external force is applied to the photographing device 400 and rotation occurs around an axis perpendicular to the plane of the paper in FIG. do. Optical axis correction signal generation circuit 402
calculates, from the output of the gyro device 401 and the zoom ratio of the optical system 405, how many times the mirror 403 for optical axis compensation 5-vane pressure should be rotated to offset the blurring of the image caused by the rotation of the photographing device 400. death,
The output is transmitted to mirror 403. The mirror 403 rotates according to the optical axis correction signal 407, and as a result, the imaging device 406
Image information with image blur corrected can be obtained. (For example, see Japanese Patent Publication No. 56-21133).

Problems to be Solved by the Invention However, in order to achieve the desired purpose in the configuration as described above, the gyro device 401 is required to have extremely high precision, and due to the problem of lifespan due to the inclusion of a high-speed rotating body. , the gyro device 401 has to be expensive. Furthermore, it is predicted that this situation will not improve in the future. Therefore, although the photographing device having the configuration described in "--" has excellent features, its field of use as a product has been extremely limited.

On the other hand, as a low friction gyro device, a vibrating gyro based on the principle of detecting angular velocity using Coriolis force is known. (
For example, US Pat. No. 2,544,646).

Since this basically detects angular velocity, it may be possible to convert the angular velocity into an angle by combining it with an integrator, and use it as an angular output in place of the gyro device of the photographing device having the above configuration. However, vibrating gyros are in principle susceptible to shocks, and it is difficult to expect stable operation in the usage environment of a photographing device simply by replacing the gyro device with the above-mentioned gyro device.

In view of the above-mentioned problems, the present invention provides a photographing device that can suppress image blur by using a low-friction vibrating gyroscope.

Means for Solving the Problems In order to solve the above-mentioned problems, the photographing device of the present invention includes a photographing means, a swing detecting means, an angular velocity detecting means, an image swing suppressing signal generating means, and an image swing suppressing means. In addition, the opposition that adds to the means of photography! The angular velocity detection means is equipped with a means for detecting the angular velocity, and a cutoff which cuts off the output of the angular velocity detection means for a predetermined period of time when the impact exceeds a predetermined value.

Effect 7 Beno The present invention has the above-described configuration, so that even if the gyro device tries to output an abnormal signal due to an impact, the impact detection means predicts the abnormality in the output of the gyro device and cuts off the output. After the transient phenomenon occurring in the gyro device due to the impact has stabilized, it becomes possible to pass the output of the gyro device again.

Embodiment Hereinafter, a photographing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a photographing device according to a first embodiment of the present invention. In FIG. 1, 108 is an imaging device for performing photoelectric conversion and extracting electrical image information, and 107 is an optical system for forming an image of a subject on the imaging device 108. Reference numeral 103 denotes a vibration-type gyro device that detects the vibration of an imaging means consisting of an optical system 107 and an imaging device 108. 104 is an angular velocity detection circuit that extracts an angular velocity component from the gyro device 103;
Reference numeral 5 designates an image fluctuation suppression signal generation circuit that generates an image fluctuation suppression signal for driving the optical axis correction mirror 106 from the output of the angular velocity detection circuit 104 and the zoom ratio information of the optical system 107. 101 is an optical system 107 and an imaging device 108
This is an impact detection sensor that is integrated with the gyro device and detects the impact applied to the gyro device, and a sensor that uses a general piezoelectric element can be used. 102 is a switch circuit that receives the output of the impact detection sensor 101 and opens and closes the output of the angular velocity detection circuit 104.

The operation of the photographing apparatus configured as described above will be described below with reference to FIGS. 1 and 2.

Note that the principle of suppressing rocking using the gyro device 103 and the mirror 106 is the same as that of the conventional example described above, so only the principle of eliminating the influence of impact, which is the object of the present invention, will be explained here.

First, FIG. 2 shows the signals of each part of the photographing device shown in FIG. This is the angular velocity signal obtained by If an impact that causes the output of the gyro device to become abnormal is applied to the optical system 107, the imaging device 108, and the gyro device 103 at time t19 page, a change immediately appears in the output 110 of the impact detection sensor 101. Angular velocity detection circuit 10
A change also occurs in the output 111 of No. 4 with a slight delay. This is an output completely unrelated to the rocking of the photographing means 107 and 108, and if this is transmitted to the rocking suppression signal generation circuit that follows next, an erroneous rocking suppression signal will be generated. is rejected. Note that the delay of the angular velocity signal 111 with respect to the impact signal 110 is caused by the angular velocity detection circuit 104. When the impact signal 11o reaches a large set value er, the switch circuit 102 immediately switches the angular velocity detection circuit 1
Cut off the output of 04.

Even if the impact attenuates over time and the impact signal 110 becomes smaller, the gyro device 103 and the angular velocity detection circuit that once produced an abnormal output will still continue to output the abnormal output due to a transient phenomenon. The switch circuit 102 changes from time t2 to time t, when this transient phenomenon ends and the output becomes stable.

When ff has elapsed, 107, -7 At time t3, the output of the angular velocity detection circuit 104 is again connected to the swing suppression signal generation circuit. Here, the threshold value er is determined by the sensitivity of the impact detection sensor 101, the strength of the gyro device 103 against impact, etc., and the cutoff time t of the switch still remains. f
f is determined by the mechanical structure and material of the imaging device 100 and the gyro device 103, the time constant of the filter circuit included in the angular velocity detection circuit 104, and the like.

As a result, the signal 11 applied to the vibration suppression signal generation circuit
2 is the signal 111 obtained by removing the abnormal output due to impact. Therefore, the influence of abnormal output due to impact of the gyro device 103 can be eliminated.

Next, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a block diagram showing a part of a photographing device using a vibrating gyroscope according to a second embodiment of the present invention. In FIG. 3, a swing and impact detection means 306, an angular velocity detection means 309, and a cutoff 313 are shown in the photographing device. Swinging and "11,,-',.

The shock detection means 306 includes a detection piezoelectric element 303 coupled to the drive piezoelectric element 302 and a drive piezoelectric element 302.
It consists of a drive circuit 301 for vibrating, a charge amplifier 3o4 for converting the charge of the detection piezoelectric element 303 caused by stress strain into voltage, and a bandpass filter 305 for removing noise from the output of the charge amplifier 304. ing. The angular velocity detection means 309 includes a synchronous detector 307 and a low-pass filter 308 for synchronously rectifying the output of the band-pass filter 305 using the drive phase reference signal from the drive circuit 3o1. Blocking means 31
3 is a window comparator 310 that receives the output of the band pass filter 306 and becomes active when the output exceeds a predetermined value, and a window comparator 310 that activates the output immediately when the output of the window comparator becomes active, and after a predetermined time elapses. Timer circuit 31 whose output is inactive
1 and a switch 312 that is opened and closed by the output of the timer circuit 311. The difference from the configuration in FIG. 1 is that in FIG.
3 was separated j ~, but in Figure 3 these are 30
The point is that they are integrated as 6.

The operation of the photographing device configured as described above will be explained below. 1. The swing and impact detection means 306 includes:
There is a drive circuit 301 and a drive piezoelectric element 302 that vibrate the detection piezoelectric element 303 at a constant amplitude and frequency, and the following three stresses act on the detection piezoelectric element 303. One is the force associated with inertial mass drive due to vibration, the other is the Coriolis force that acts when there is an angular velocity around the swing detection axis, and the last is the force due to impact. These forces appear as electrical signals at the output of the bandpass filter 305 through stress strain-to-charge conversion by the detection piezoelectric element 303 and charge-to-voltage conversion by the charge amplifier 304. The voltage generated by the first inertial mass drive is always generated, and its signal is an AC voltage that is 90 degrees out of phase with the drive phase reference signal obtained from the drive circuit 301. Next, the angular velocity 1 generated due to the shaking of the imaging device
38-] is an alternating current voltage that is in phase with the drive phase reference signal. The signal generated by the shock is then a signal that is completely unrelated to the drive phase reference signal.

Therefore, if the output of the band pass filter 305 is synchronously rectified based on the drive phase reference signal like the angular velocity detection means 309, the signal due to the angular velocity can be separated from the signal associated with the inertial mass drive.

However, when an impact occurs, it is impossible to avoid signal mixing due to this impact. On the other hand, when an impact occurs, the output amplitude of the bandpass filter 305 changes significantly, so this is detected by the wind comparator 310.
can be detected by

As described above, by using the vibrating gyroscope, the swing detection means can also serve as a part of the impact detection means.

Effects of the Invention As described above, the present invention makes it possible to use a vibrating gyroscope that is weak against shocks in the above-mentioned photographic device by providing a shock detection means and a signal cut-off means, and also makes it possible to use a photographing device with an image pre-suppressing function. It can be realized in a low position.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a photographing device according to a first embodiment of the present invention, and FIG. 2 is a waveform diagram showing signals of each part in FIG. 1.
FIG. 3 is a block diagram of a part of the imaging device according to the second embodiment of the present invention, FIG. 4 is a block diagram of a conventional imaging device, and FIG. 5 is a perspective view showing the configuration of the gyro device shown in FIG. 4. The diagram shows 0100... photographing device, 101...
・Shock sensor, 102...Switch circuit, 10
3... Gyro device, 104... Angular velocity detection circuit, 105... Image fluctuation suppression signal generation circuit, 106... Mirror for optical axis correction, 107... ...
...Optical system, 108...Imaging device.

Claims (2)

[Claims] (1) Photographing means for photographing a subject to obtain a photographed image; rocking detection means for detecting rocking of the photographing means and outputting a rocking detection signal; and angular velocity detection for detecting angular velocity from the rocking detection signal. an impact detecting means for detecting an impact applied to the photographing means; and a blocking means for cutting off the output of the angular velocity detecting means for a predetermined period of time when the impact applied to the photographing means by the impact detecting means exceeds a predetermined value. , an image swing suppression signal generation means for outputting an image swing suppression signal in response to the output of the angular velocity detection means that has undergone the cutoff; the image swing suppression signal generation means; and the image swing suppression signal. and an image fluctuation suppressing means configured to suppress fluctuation of the photographed image in response to the vibration. (2) The photographing device according to claim (1), wherein the swing detection means is a part of the impact detection means.