JPH04301822A - Camera with anti-shake function - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is directed to a camera with an anti-shake function that detects vibrations (hand shake) with a frequency of about 1Hz to 12Hz and uses this information as information to prevent image shake. It is about improvement.

0002

BACKGROUND OF THE INVENTION The prior art to which the present invention is applied will be explained below.

[0003] In modern cameras, all important tasks for photography, such as exposure determination and focus adjustment, are automated, so even those who are inexperienced in operating the camera are less likely to make a mistake in taking a picture. However, it has been difficult to automatically prevent failures in photography due to camera shake.

[0004] Therefore, in recent years, there has been active research into cameras that can prevent shooting failures caused by camera shake, and in particular, cameras that can prevent shooting failures due to camera shake. Development and research is underway.

[0005] The above-mentioned hand shake of the camera during photography usually has a frequency of 1Hz to 12Hz, but even if such hand shake occurs at the time of shutter release, it is possible to take a picture without image blur. As a basic idea, it is necessary to detect the vibration of the camera due to the above-mentioned camera shake, and to displace the correction lens according to the detected value. Therefore, in order to achieve the above purpose (i.e., to be able to take photographs that do not cause image blur even when the camera shakes), the first step is to accurately detect camera vibration, and the second is to accurately detect camera vibration.
It is necessary to correct optical axis changes caused by camera shake.

In principle, detection of this vibration (camera shake) requires a vibration sensor that detects angular acceleration and angular velocity, and a vibration sensor that electrically or mechanically integrates the sensor signal and outputs angular displacement. This can be done by mounting a means on the camera. Then, based on this detection information, a correction optical mechanism (the correction optical means and its driving means are collectively referred to as a correction optical mechanism) that decenters the photographing optical axis is driven to suppress image blur.

[0007] Here, an outline of an image stabilization system (shake prevention system) using an angular accelerometer will be explained with reference to FIG.

The example shown in FIG. 6 is a diagram of a system for suppressing image blur caused by vertical camera shake 51p and horizontal camera shake 51y in the direction of arrow 51.

In the figure, 52 is a lens barrel, 53p, 53
y is an angular accelerometer that detects the camera vertical shake angular acceleration and the camera horizontal shake angular acceleration, and the respective angular velocity detection directions are indicated by 54p and 54y. 55p and 55y are known analog integration circuits, which integrate the signals of the angular accelerometers 53p and 53y and convert them into camera shake angular displacement, and use the signals to control the correction optical mechanism 56 (57p and 57y are the driving parts thereof, respectively).
8p and 58y drive correction optical position detection sensors (correction optical position detection sensors) to ensure stability on the image plane 59. Incidentally, it is also possible to provide the correction optical mechanism 56 itself with a mechanical integration function and omit the analog integration circuit described above.

FIG. 7 is a diagram showing the configuration of a correction optical mechanism suitably used in such a system.
and yaw direction 31y (corresponding to 51p and 51y)]. Its configuration is shown below.

In FIG. 7, a fixed frame 33 holding a correction lens 32 is connected to a pitch slide shaft 35 via a sliding bearing 34p made of polyacetal resin (hereinafter referred to as POM) or the like.
It is designed to be able to slide on p. The fixed frame 33 also has a pitch coil spring 37p coaxial with the pitch slide shaft 35p.
It is held near the neutral position. The pitch slide shaft 35p is attached to the first holding frame 36.

Pitch coil 3 attached to fixed frame 33
8p is pitch magnet 39p and pitch yoke 310p
The fixed frame 33 is placed in a magnetic circuit composed of a magnetic circuit, and the fixed frame 33 is driven in the pitch direction 31p by passing a current. Further, the pitch coil 38p is provided with a pitch slit 311p, and the position of the fixed frame 33 in the pitch direction 31p is determined by the relationship between the light emitting element 312p (infrared light emitting diode) and the light receiving element 313p (semiconductor position detection element). Perform detection.

A sliding bearing 34y such as a POM is fitted into the first holding frame 36, and can slide on a housing 314 to which a yaw slide shaft 35y is attached. Since the housing 314 is attached to the lens barrel 52 shown in FIG. 6, the first holding frame 33 is movable in the yaw direction 31y with respect to the lens barrel 52. Also, yaw slide axis 3
A yaw coil spring 37y is provided coaxially with 5y,
Like the fixed frame 33, it is held near the neutral position.

The fixed frame 33 also has a yaw coil 38y.
The fixed frame 33 is also driven in the yaw direction 31y by the yaw magnet 39y and yaw 310y that sandwich the yaw coil 38y. Above yaw coil 38y
A yaw slit 311y is provided to detect the position of the fixed frame 33 in the yaw direction 31y as well as in the pitch direction.

In FIG. 7, light receiving elements 313p, 313
The output of y is amplified by amplifiers 315p and 315y and sent to a coil (pitch coil 38) through each circuit (described later) as shown in the figure.
When input to the p and yaw coils 38y), the fixed frame 33 is driven and the outputs of the light receiving elements 313p and 313y change. Here, if the driving direction (polarity) of the coils 38p, 38y is set in the direction in which the output of the light receiving elements 313p, 313y becomes smaller, a closed system (closed loop) is formed, and the light receiving elements 313
It becomes stable at the point where the output of p, 313y becomes almost zero.

Note that the compensation circuits 316p and 316y are shown in FIG.
This is a circuit that makes the system more stable, and the adder circuit 319p
, 319y are circuits that add the input command signals 318p, 318y to the amplifiers 315p, 315y, and drive circuits 317p, 317y are circuits that supplement the current applied to the coils 38p, 38y.

A command signal 318p is sent to the system as described above from the outside.
, 318y, the correction lens 32 moves in the pitch direction 3
The command signals 318p and 318y are applied to 1p and yaw direction 31y.
is driven extremely faithfully.

FIG. 8 is a diagram showing the driving means for driving the correction optical means in more detail.
I will only explain about.

Current-voltage conversion amplifiers 325a, 325b
The light emitting element 312p causes the light receiving element 313p (resistance R1
, R2), and the differential amplifier 320 converts the photocurrent generated in the current-to-voltage conversion amplifiers 325a, 32
5b, and this difference signal represents the position of the correction lens 32 in the pitch direction 31p. As described above, the current-voltage conversion amplifiers 325a, 325b, the differential amplifier 320, and the resistors R3 to R10 constitute the amplifier 315p in FIG.

The amplifier 321 adds the command signal 318p to the difference signal of the differential amplifier 320, and is connected to the resistor R1.
1 to R14 constitute an adder circuit 319p in FIG.

The resistors R15 and R16 and the capacitor C1 are a known phase lead circuit, which is the compensation circuit 31 of FIG.
It corresponds to 6p and stabilizes the system.

The output of the adder circuit 319p is sent to the compensation circuit 3.
The signal is input to the drive amplifier 322 via the signal line 16p, where a drive signal for the coil 38p is generated, and the correction lens 32 is displaced. The drive amplifier 322, resistor R17, and transistors TR1 and TR2 constitute the drive circuit 317p in FIG.

The summing amplifier 323 calculates the sum of the outputs of the current-voltage conversion amplifiers 325a and 325b (the total amount of light received by the light receiving element 313p), and the driving amplifier 324 receives this signal.
drives the light emitting element 312p in accordance with this. As above, addition amplifier 323, drive amplifier 324, resistor R18~
R22 and the capacitor C2 constitute a drive circuit for the light emitting element 312p (not shown in FIG. 7).

The amount of light emitted by the light emitting element 312p changes extremely unstablely depending on the temperature, etc., and accordingly, the differential amplifier 3
Although the positional sensitivity of the light emitting element 312p changes, the drive circuit described above controls the light emitting element 312p so that the total amount of light received remains constant as described above.
If this is controlled, the position sensitivity will not change.

[0025] Furthermore, in the case of constructing an image blur suppression system by detecting very delicate vibrations such as camera vibrations distributed in a low frequency range of 1Hz to 12Hz, the detection is performed. The angular acceleration sensor 53p for
, 53y are required to be highly accurate, and FIG. 9 shows a structural diagram of a conventional servo angular acceleration sensor suitable for such purposes.

In FIG. 9, 428 is the bottom of the outer frame;
A support portion 429 that is integrally fixed to this outer frame bottom portion 428
and bearings 430a, 4 with low friction such as ball bearings.
Both ends of the shaft 431 are supported by 30b,
A seesaw 434 to which coils 432a and 432b are attached is swingably supported by the shaft 431.

Above and below the coils 432a, 432b and seesaw 434, magnetic circuit boards 435a, 435b and permanent magnets 436a1, 4 are spaced apart from these and serve as lids.
36a2, 436b1, and 436b2 are arranged facing each other, and the magnetic circuit boards 435a and 435b also serve as the lid portion of the outer frame as described above. Permanent magnets 436a1, 436a
2,436b1 and 436b2 are mounted on magnetic circuit back plates 437a and 437b, respectively, which are fixed to the bottom of the outer frame 428.

[0028] Also, the coil 432a of the seesaw 434
, 432b has a slit 43 penetrating in the thickness direction.
Slit plates 439a, 439 forming 8a, 438b
b, and the magnetic circuit board 435a, which also serves as the lid of the outer frame above the slit 438a, is made of SPC (Se
A photoelectric displacement measuring device 440, such as a photodiode, is arranged, and a light emitting element 441, such as an infrared light emitting diode, is arranged on the magnetic circuit back plate 437a below the slit 438a.

In the above configuration, if the angular acceleration a acts on the outer frame in FIG. 9 as shown by the arrow, the seesaw 434 tilts in the direction opposite to the angular acceleration a,
This deflection angle is determined by the light emitting element 441 passing through the slit 438a.
This can be detected by the position of the beam on the displacement measuring device 440.

By the way, the permanent magnets 436a1, 43
The magnetic flux from 6b1 is transmitted to permanent magnets 436a1 and 436, respectively.
b1 → Coils 432a, 432b → Magnetic circuit board 435a
, 435b → Coil 432a, 432b → Permanent magnet 43
6a2, 436b2, the other permanent magnet 436a2, 43
The magnetic flux from 6b2 is transmitted to permanent magnets 436a2 and 436, respectively.
a2 → Magnetic circuit back plate 437a, 437b → Permanent magnet 43
6a1 and 436b1, forming a closed magnetic circuit as a whole, and forming magnetic flux in a direction perpendicular to the coils 432a and 432b. and coil 4
By flowing a control current through 32a and 432b, the seesaw 434 can be moved to both sides along the deflection direction of the angular acceleration a according to Fleming's law.

FIG. 10 shows an example of the configuration of an angular acceleration detection circuit used in the servo angular acceleration sensor having the above configuration.

This circuit includes a displacement detection amplifier 442 for amplifying the output from the displacement detector 440, and a compensation circuit 443 for making this feedback circuit a stable circuit system.
The drive circuit 444 further amplifies the amplified output from the displacement detection amplifier 442 and energizes the coils 432a and 432b, and the coils 432a and 432b are connected in series.

In this example, the coil 432
When electricity is applied to a and 432b, the external angular acceleration a
The winding direction of the coils 432a, 432b and the permanent magnets 436a1, 436a2, 436b1, 436b are adjusted so that force is generated in the opposite direction to the deflection direction of the seesaw 434 due to the
2 polarities are set.

To explain the operating principle of the servo angular acceleration sensor with the above configuration, if angular acceleration a is applied from the outside to the angular acceleration sensor with the above configuration as shown in FIG. The force swings in the opposite rotational direction relative to the outer frame, and therefore the slit 438a provided in the seesaw 434 moves in the L direction. For this reason, the center of the light beam incident on the displacement detector 440 from the light emitting element 441 is displaced, and the displacement detector 440 generates an output proportional to the amount of displacement.

The output is sent to the displacement detection amplifier 44 as described above.
2, and is further amplified by the drive circuit 4 via the compensation circuit 443.
The current is amplified by 44 and energized to coils 432a and 432b.

As described above, when the control current is applied to the coils 432a and 432b, a force is generated in the seesaw 434 in the R direction, which is the opposite direction to the L direction of the external angular acceleration a, resulting in displacement. A control current is adjusted and generated so that the light beam incident on the detector 440 returns to its initial position when the external angular acceleration a is not applied.

At this time, the value of the control current flowing through the coils 432a and 432b is proportional to the rotational force applied to the seesaw 434, and furthermore, the rotational force applied to the seesaw 434 is proportional to the rotational force applied to the seesaw 434 from the origin. Since the returning force is proportional to the magnitude of the external angular acceleration a, the current flows through the resistor 445 to the voltage V.
By reading this, the magnitude of the angular acceleration a can be obtained as control information necessary for, for example, a camera image blur suppression system.

FIG. 11 is a diagram showing the angular acceleration detection circuit of FIG. 10 in more detail.

In FIG. 11, the current-voltage conversion amplifier 4
46 and resistors 447 and 448 correspond to the displacement detection amplifier 442 in FIG. 10, and perform position detection by converting and amplifying the photocurrent from the displacement measuring device 440 into voltage. Capacitor 449 and resistors 450 and 451 correspond to compensation circuit 443, and drive amplifier 452, resistors 453, 454 and 457 and transistors 455 and 456 correspond to drive circuit 444 that drives coils 432a and 432b. Also, 440,441
are the displacement detector and light emitting element described above.

By the way, the angular acceleration sensor electrically integrates its output (analog integration circuit 55p in FIG.
55y corresponds to this), it is necessary to find the angular displacement, but as already mentioned, there is also a type of vibration sensor that includes a mechanical integral action itself.

FIGS. 12 to 14 show the configuration of such an angular displacement detection device, and will be explained below using these figures.

In FIGS. 12 to 14, reference numeral 1 denotes a base plate on which each part constituting the device is attached, and 2 a floating body 3, which will be described later, inside.
and an outer cylinder having a chamber containing a liquid 4. 3 is axis 3b
The floating body is rotatably held by a floating body holder 5 (described later), and the protrusion 3a has a slit-shaped reflective surface, and is made of a material made of a permanent magnet.
It is magnetized in the direction. Further, this floating body 3 is configured to have a rotational balance around the shaft 3b and a buoyancy balance.

A floating body holder 5 is fixed to the outer cylinder 2 while holding the floating body 3 via a pivot bearing 13, which will be described later. Reference numeral 6 denotes a U-shaped yoke attached to the main plate 1, which forms a closed magnetic path together with the floating body 3. Reference numeral 7 denotes a winding coil, which is disposed between the floating body 3 and the yoke 6 and is provided in a fixed relationship with the outer cylinder 2. Reference numeral 8 denotes a light emitting element (iRED) that generates light when energized, and is attached to the base plate 1. Reference numeral 9 denotes a light receiving element (PSD) whose output changes depending on the position of the received light, and is attached to the base plate 1. The light-emitting element 8 and the light-receiving element 9 constitute optical angular displacement detection means that transmits light through the protrusion (reflection surface) 3a of the floating body 3.

Reference numeral 10 denotes a mask placed in front of the light emitting element 8, and has a slit hole 10a through which light passes. 1
Reference numeral 1 denotes a stopper member attached to the outer cylinder 2, which restricts rotation of the floating body 3 so that it does not rotate beyond a predetermined range.

The above-mentioned floating body 3 is held rotatably in the following manner. In other words, at the center of the floating body 3 there is a
As shown in (A-A cross section in FIG. 12), pivots 12 with sharp tips are press-fitted at the top and bottom. On the other hand, pivot bearings 13 are provided at the ends of the U-shaped upper and lower arms of the floating body holder 5 so as to face each other inwardly.
The floating body is held by fitting the sharp tip of the pivot bearing 13 into the pivot bearing 13.

Reference numeral 14 designates the upper lid of the outer cylinder 2, which is sealed and bonded to the outer cylinder 2 by a known technique using silicone adhesive or the like to seal the liquid 4 inside the outer cylinder 2.

In the above configuration, the floating body 3 is rotated around the rotating shaft 3b so that no rotational moment is generated due to the influence of gravity in any posture, and no load is substantially applied to the pivot shaft. It has a symmetrical shape and is made of a material with the same specific gravity as the liquid 4. In reality, it is impossible to have zero unbalance component, but since only the difference in specific gravity acts as an unbalance for the shape error, it is practically small enough, and the S/N ratio of friction to inertia is extremely good. can be easily understood.

In such a configuration, the outer cylinder 2 is connected to the rotating shaft 3.
Even if it rotates around b, the internal liquid 4 remains stationary with respect to absolute space due to inertia, so the floating body 3 does not rotate, and therefore the outer cylinder 2 and floating body 3 rotate relative to each other around the rotation axis 3b. I will do it. These relative angular displacements can be detected by optical detection means using the light emitting element 8 and light receiving element 9.

Now, in the apparatus having the above configuration,
Angular displacement detection is performed as follows.

First, the light emitted from the light emitting element 8 passes through the slit hole 10a of the mask 10 and is irradiated onto the floating body 3.
Here, the light is reflected by the slit-shaped reflective surface of the protrusion 3a and reaches the light receiving element 9. When the light is transmitted, the light becomes approximately parallel light due to the slit hole 10a and the slit-like reflecting surface, and an unblurred image is formed on the light receiving element 9.

Since the outer cylinder 2, the light emitting element 8, and the light receiving element 9 are all fixed to the base plate 1 and move together, relative angular displacement movement between the outer cylinder 2 and the floating body 3 When this occurs, the slit image on the light receiving element 9 moves by an amount corresponding to the displacement. Therefore, the output of the light receiving element 9, which is a photoelectric conversion element whose output changes depending on the position of the received light, is an output proportional to the positional displacement of the slit image, and the angular displacement of the outer cylinder 2 is detected using this output as information. can do.

By the way, as mentioned above, the floating body 3
It is made of a permanent magnet material having the same specific gravity as the magnet, and it is made in the following manner, for example.

When a fluorine-based inert liquid is used as the liquid 4, if fine powder of a permanent magnet material (for example, ferrite, etc.) is contained as a filler in a plastic material base and the content is adjusted, the volume can be increased. It is easy to make the specific gravity similar to the liquid's specific gravity "1.8" at a content of around 8%. If the floating body 3 is molded from such a material or simultaneously magnetized in the direction of the axis 3b, the floating body 3 will have properties as a permanent magnet.

FIG. 15 shows the floating body 3, yoke 6, and winding coil 7.
13 is a cross section taken along line B-B in FIG. 12 showing the relationship.

As shown in the figure, the floating body 3 is magnetized in the direction of the axis 3b, and in this figure, the upper side is magnetized as the north pole and the lower side as the south pole. The lines of magnetic force coming out from the N pole pass through the U-shaped yoke 6 and enter the S pole, forming a closed magnetic path. When a current flows from the back side to the front side, the wire-wound coil 7 receives a force in the direction of arrow f according to Fleming's left-hand rule. However, as mentioned above, the winding coil 7 cannot move because it is fixed to the outer cylinder 2, so a reaction force acts in the direction of arrow F, and the floating body 3 is driven by this force. That will happen. It goes without saying that this force is proportional to the current flowing through the winding coil 7, and that the force acts in the opposite direction if the current is caused to flow in the opposite direction. That is, in the above configuration, it is possible to freely drive the floating body 3.

The spring force exerted on the floating body 3 by this driving force is, in principle, a force that maintains the floating body 3 in a constant attitude relative to the outer cylinder 2 (that is, moves it integrally).
If the spring force is strong, the outer cylinder 2 and the floating body 3 will move as one, causing the problem that the relative angular displacement for the desired angular displacement will not occur, but the driving force (spring force) As long as it is sufficiently small relative to the inertia of the floating body 3, it can be configured to respond to angular displacements at relatively low frequencies.

FIG. 16 is a diagram showing an electric circuit of the angular displacement detection device as described above.

The current-voltage conversion amplifiers 17a, 17b (and resistors R33 to R36) convert the photocurrents 16a, 16b generated in the light receiving element 9 by the reflected light 15 of the light emitting element 8 into voltages. R37 to R40) determine the output difference between the current-voltage conversion amplifiers 17a and 17b, that is, the angular displacement (relative angular displacement movement between the outer cylinder 2 and the floating body 3). This output is divided by resistors 19 and 20 to make an extremely small output, and a drive amplifier 21 (and resistor R41, transistors TR11, TR
12) and perform negative feedback (set the wiring of the winding coil 7 and the magnetization direction of the floating body 3 so that the floating body 3 returns to the center when the differential amplifier 18 outputs it), as described above. A spring force (driving force) that is sufficiently small relative to the inertia of the liquid 4 is generated.

Adding amplifier 23 (and resistors R42 to R45)
calculates the sum of the amplifiers 17a and 17b (total amount of received light 15 from the light-emitting element 8 of the light-receiving element), and uses the output from the drive amplifier 24 (and resistors R47 to R48, transistors) that causes the light-emitting element 8 to emit light. It is input to TR13 and capacitor C11).

Although the light emitting element 8 changes its light emission amount extremely unstablely due to temperature differences, if the light emitting element 8 is driven by the total amount of received light as described above, the total photocurrent output from the light receiving element 9 will change. is always constant, and the angular displacement detection sensitivity of the differential amplifier 18 can be made extremely stable.

[0061]

[Problems to be Solved by the Invention] Driving of the correction optical means and vibration detection means (servo angular acceleration sensor,
Each drive of the angular displacement detection device (angular displacement detection device) constitutes a known position control loop, and also between light emission (light emission) and light reception for position detection of the correction optical means and angular displacement detection of the vibration detection means. The light emission is controlled so that the amount of light is constant.

[0062] Then, their position control and light projection control rules
The following problems arise due to this.

1) Problems with the position control loop In the correction optical mechanism shown in FIG.
Consider the case where it stops moving at p. At this time, slit 3
Since there is no change in the position of the light receiving element 313p, the output of the light receiving element 313p remains at a constant value and does not change. This shows that the differential amplifier 320 always has a constant output in FIG.

When the drive is performed normally, the command signal 31
8p, the correction lens 32 is driven extremely faithfully, and the output of the differential amplifier 320 is approximately equal to the command signal 318p. This is because the amplifier 321 is the sum of the output of the differential amplifier 320 and the output of the command signal 318p (actually, the amplifier 321 is the sum of the output of the differential amplifier 320 and the output of the command signal 318p).
Since the output of 20 and the output of command signal 318p are in opposite phase,
The error output (difference between these two outputs) is the error output (correction lens 32
This is because the output of the differential amplifier 320 is brought closer to the command signal 318p by extremely amplifying (increasing the position loop gain) the amount that cannot follow the command signal 318p and driving the pitch coil 38p.

However, as described above, if the output of the differential amplifier 320 is always constant, the output of the amplifier 321 will greatly amplify the error between the constant output of the differential amplifier 320 and the output of the command signal 318p. Differential amplifier 32 so far
Since the output of 0 was close to the command signal 318p, even if the error was amplified by a large amount, there would be no problem because the original error was small, but since the original error was large, a large output (large current) was applied to the pitch coil 38p. I end up giving it to.

The same thing applies to the servo angular acceleration sensor shown in FIG. 9, and if the ball bearings 430a and 430b are damaged and the seesaw 434 does not come close to neutral, the circuit shown in FIG. In an attempt to return 434 to neutral, a large current is passed through coils 432a and 432b.

As mentioned above, if a large current continues to flow through the coils (38p, 38y or 432a, 432b), it goes without saying that the power supply will be consumed and functions other than the vibration isolation system will deteriorate accordingly. Otherwise, the heat generated by the coil will cause damage to surrounding components.

2) Problems with the light projection control loop Consider the case where dust or the like adheres to the slit 311p in the correction optical mechanism shown in FIG. At this time, since the amount of light received by the light receiving element 313p decreases, the adding amplifier 323, drive amplifier 324, etc. shown in FIG.
Increase the current flowing to the

This also applies to the angular displacement detection devices shown in FIGS. 12 to 16.

For this reason, if there is a large amount of dust or the like that greatly blocks the amount of light emitted (light emitted), the light emitting elements (312p, 312y
Alternatively, the current flowing through 8) becomes a huge value, and, similar to the problem with the position control loop, it consumes the power supply and deteriorates functions other than the anti-vibration system. The problem is damage to each member.

[0071] In view of the above points, an object of the present invention is to prevent unnecessary consumption of the power supply and damage to surrounding components due to abnormalities in the vibration isolation system. To provide a camera with an anti-shake function that can notify you when an abnormality occurs in an anti-shake system.

[0072]

[Means for Solving the Problems] The present invention provides an abnormality detection means for detecting an abnormality in the operation of a vibration isolation system, and a function stop that stops the function of the vibration isolation system when an abnormality is detected by the abnormality detection means. and further, the function stop means includes a stop means for stopping the function of only the means in which the abnormality has occurred among the means constituting the vibration isolation system, and
The apparatus includes a warning means that issues a warning when an abnormality is detected by the abnormality detection means.

[0073]

[Operation] When an abnormality in the vibration isolating system is detected by the abnormality detecting means, the function stopping means stops the function of the vibration isolating system itself, stops the function of only the means causing the abnormality, or warns the user. The means issues a warning if an abnormality is detected by the abnormality detection means.

[0074]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing a first embodiment of the present invention, and in the figure, the subscripts p and y of each reference sign indicate means for vibration isolation in the pitch direction and yaw direction, respectively.

In FIG. 1, 111p, 111y, 11
3p and 113y are abnormality detection means, each of which is comprised of a known current detection means using MOSFET or the like and a comparator that outputs an abnormality detection signal when the current value exceeds a certain level. (Since such a configuration is publicly known, its explanation will be omitted). 112p, 112y, 11
4p, 114y are the abnormality detection means 111p, 111y.
, 113p, 113y, and stops the current supply to each means of the vibration damping system, and is composed of, for example, a relay. Reference numerals 115p and 115y are vibration detection means constituted by the aforementioned servo angular accelerometer and integrator or angular displacement detection device. 116p, 1
Reference numeral 16y denotes a driving means for driving the correction optical means 117 (corresponding to the part numbered in the 30s in FIG. 7), which corresponds to the driving circuits 317p and 317y shown in FIG. 8. 118 is abnormality detection means 111p, 111y, 1
An OR gate 119 receives the abnormality detection signals from 13p and 113y, respectively, and is a display driving means for lighting or blinking an abnormality warning means 121 disposed within the finder 120 of the camera. Further, Vcc is a power supply voltage.

In the above configuration, as described above, when the correction optical means 117 stops moving, for example, in the yaw direction due to scratches or the like, the driving means 116y starts to flow a large current to the yaw coil 38y of the correction optical means 117. Then, the abnormality detection means 113y outputs an abnormality detection signal, and the function stop means 114y that receives this signal immediately stops the current supply to the drive means 116y. This prevents damage to the outside and rapid consumption of the power source due to heat generated by the yaw coil 38y.

Further, the abnormality detection signal from the abnormality detection means 113y is transmitted to the display driving means 1 via the OR gate 118.
19 and abnormality warning means 1 in the finder 110
Turn on 21. This makes it possible to notify the photographer that an abnormality has occurred in the image stabilization system. Incidentally, the abnormality warning means 121 may include not only such a display in the finder but also a sound or voice.

[0078] Also, for example, if dust adheres in front of the light receiving element (not shown in Fig. 1) of the angular displacement detecting device in the pitch direction, and a large current begins to flow to the light emitting element (not shown in Fig. 1), the same problem occurs. The abnormality detection means 111p outputs an abnormality detection signal and stops the current supply to the angular displacement detection device.
will stop. Therefore, the heat generated by the light emitting element,
Destruction can be prevented and the abnormality warning means 121 can be turned on to give a warning.

In the above configuration, for example, the driving means 11
6p, a large current often instantaneously flows through the vibration detection means 115p, and this is when a large vibration (hand shake) is detected and the correction optical means 117 is driven to follow it. At this time, although the above-mentioned abnormality itself does not occur, there is a possibility that an abnormality detection signal is output from the abnormality detection means 111p. In order to avoid this kind of thing, if you connect a low-pass filter etc. in series to the output of each abnormality detection means and configure it so that the abnormality detection signal is not output in response to an instantaneous large current, it will be possible to Does not cause any problems.

In the above-described configuration, only the drive means on the side where the abnormality has occurred is stopped, so even if the function of the vibration detection means 115y in the yaw direction or the drive means 116y stops, the pitch cannot be changed. Directional vibration isolation can still be performed.

FIG. 2 is a diagram showing a second embodiment of the present invention, and the same parts as in FIG. 1 are given the same reference numerals.

This second embodiment is an example in which, when vibration isolation is performed on only one side as in the first embodiment, an abnormality warning is displayed only in the direction in which vibration isolation cannot be achieved. The difference from 1 is that the abnormality detection signals from the abnormality detection means 111y and 113y are input to the OR gate 118y, and the output of this OR gate 118y is input to the display driving means 19y for lighting the abnormality warning means 121y. Also, abnormality detection means 1
Anomaly detection signals from 11p and 113p are sent to OR gate 11.
8p, and the output of this OR gate 118p is input to the display driving means 19p which turns on the abnormality warning means 121p.

[0083] For example, the drive means 116 in the yaw direction
When an abnormality occurs in the drive means 1, the abnormality detection signal from the abnormality detection means 113y causes the function stop means 114y to
16y, and at the same time the abnormality detection means 1
The abnormality detection signal from 13y is inputted to the display driving means 119y via the OR gate 118y and sent to the abnormality warning means 121.
Turn on y. Therefore, the photographer can know the axis in which the anti-shake is no longer effective, and therefore only needs to be careful when shooting in the yaw direction, where the anti-shake is no longer effective, or, for example, for panning in the yaw direction. The photographer can know that the camera can be used without any problems when doing the following.

FIG. 3 is a diagram showing a third embodiment of the present invention, and the same parts as in FIGS. 1 and 2 are given the same reference numerals.

As in the first and second embodiments, when the driving means 116p or 116y stops functioning, the correction optical means 117 becomes free. This is because the correction optical means 1 had become slow due to dust etc.
17 may also start moving due to some kind of impact (hitting the camera or a large hand shake), and of course, in preparation for such a case, if you turn on the main switch of the camera again, the abnormality detection means on the side where the abnormality occurred will be detected. An abnormality detection signal is not generated, and the function of the means in which the abnormality occurred is operated to recover. -, the obtained photograph will be extremely deteriorated (for example, the function of the driving means 116y will stop and the correction optical means 117 will become free to move in the yaw direction, and the correction lens will If 32 wobbles in the yaw direction, the photo will result in a large shake in that direction).

This third embodiment is intended to solve the above-mentioned problems, and is different from FIG. Relays 132p and 132y receive abnormality detection signals from abnormality detection means 113p and 113y, respectively, and switch constant power supply 131 to pitch and yaw coils 38p and 38y.
Connect to.

[0087] The constant power source 131 has coils 38p, 38
The voltage is adjusted to be sufficient to generate less heat in y and to keep the correction lens 32 biased and fixed at either end (for example, the right end in the pitch direction).

Therefore, when the movement of the correction optical means 117 in the yaw direction becomes slow due to dust etc., and the function stop means 114y stops supplying current to the drive means 116y, the same parts as in FIG. (However, here, the circuit configuration in the yaw direction is shown.) As shown in the figure, the relay 13
2y connects the constant power source 131 to the yaw coil 38y to continue applying force to the correction optical means 117 in a constant direction in the yaw direction. If dust or the like is attached, the correction optical means 117 will not move, but even if the dust is removed and the correction optical means 117 becomes free, the correction optical means 117 will move to either end in the yaw direction. Since it is fixed in place, it does not wobble during shooting, preventing extreme deterioration of the photo.

FIG. 5 is a diagram showing a fourth embodiment of the present invention, and parts having the same functions as those in FIGS. 1 to 3 are given the same reference numerals.

The difference from FIG. 1 is that the vibration isolation system itself is configured to stop upon receiving an abnormality detection signal from the abnormality detection means 141.

In FIG. 5, the abnormality detection means 141 outputs an abnormality detection signal even if an abnormality occurs in any of the means (vibration detection means 115p, 115y, driving means 116p, 116y). Then, the abnormality warning means 111 is turned on via the display drive means 119, and the abnormality detection signal is output in the direction of the arrow 142, thereby switching the vibration isolation system operation switching means (not shown) to the vibration isolation system non-operation state. .

With such a configuration, the circuit configuration can be extremely simplified and miniaturized as shown in FIG. 5.

According to each of the embodiments described above, the function of the vibration isolating system (the whole or only the part where the abnormality has occurred) is controlled by the means for detecting an abnormality in the vibration isolating system and the abnormality detection signal from the means. ), it is possible to prevent abnormal power consumption and damage to other functions due to heat generation of the coil and light emitting element, and also to warn the photographer of abnormalities in the anti-shake system. By doing so, we were able to prevent the photographer from taking pictures without noticing the vibration isolation abnormality.

(Modification) The abnormality detection means in each of the above embodiments is assumed to be composed of a known current detection means and a comparator that outputs an abnormality detection signal when the current value exceeds a certain level. However, it is not limited to this, and it is possible to simply provide a resistor between the power supply (Vcc) and each means,
It is also possible to detect the voltage between the terminals. Moreover, it is also possible to realize it by other methods of electromagnetically detecting current.

Furthermore, flip-flops are provided as the abnormality detecting means and the function stopping means as described above, and once the function stopping means is activated by the signal output from the abnormality detecting means, even if the abnormality detection signal is no longer generated in the abnormality detecting means, The function stop means may be configured to continue operating, and the flip-flop may be reset only by the camera main switch.

[0096]

[Effects of the Invention] As explained above, according to the present invention,
an abnormality detection means for detecting an abnormality in the operation of the vibration isolation system;
and a function stop means for stopping the function of the vibration isolation system when an abnormality is detected by the abnormality detection means, and
The function stop means is provided with a stop means for stopping the function of only the means that has caused an abnormality among the means constituting the vibration isolation system, and a warning is issued when an abnormality is detected by the abnormality detection means. When an abnormality in the vibration isolation system is detected by the abnormality detection means, the vibration isolation system itself is stopped, or the function of only the means causing the abnormality is stopped, and in such cases, I am trying to issue a warning. Therefore, it is possible to prevent unnecessary consumption of the power supply and damage to surrounding components due to abnormalities occurring in the vibration isolation system. Furthermore, if an abnormality occurs in the vibration isolation system, it is possible to notify the user of this fact.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of main parts in a first embodiment of the present invention.

FIG. 2 is a diagram showing the configuration of main parts in a second embodiment of the present invention.

FIG. 3 is a diagram showing the configuration of main parts in a third embodiment of the present invention.

FIG. 4 is a circuit diagram showing the configuration of main parts in a third embodiment of the present invention.

FIG. 5 is a diagram showing the configuration of main parts in a fourth embodiment of the present invention.

FIG. 6 is a perspective view showing a schematic configuration of a conventional vibration isolation system.

7 is a diagram showing the mechanical and electrical configuration of a correction optical mechanism in the image stabilization system of FIG. 6. FIG.

8 is a circuit diagram specifically showing the electrical configuration of FIG. 7. FIG.

FIG. 9 is an exploded perspective view showing the configuration of a servo angular accelerometer, which is one of conventional vibration detection means.

10 is a block diagram showing the electrical configuration of the servo angular accelerometer shown in FIG. 9; FIG.

FIG. 11 is a circuit diagram specifically showing the electrical configuration of FIG. 10;

FIG. 12 is a plan view showing an angular displacement detection device, which is one of conventional vibration detection means.

FIG. 13 is a sectional view taken along line AA in FIG. 12;

14 is a perspective view of the angular displacement detection device shown in FIG. 12. FIG.

FIG. 15 is a sectional view showing the main part configuration of the angular displacement detection device shown in FIG. 12;

16 is a circuit diagram showing the electrical configuration of the angular displacement detection device shown in FIG. 12. FIG.

[Explanation of sign]

111p, 111y Abnormality detection means 112p, 112y Function stop means 113p, 113y Abnormality detection means 114p, 114y Function stop means 115p, 115y Vibration detection means 116p, 116y driving means

Claims (3)

[Claims] 1. A correction optical means disposed within a lens barrel holding a lens group and decentering the optical axis of the lens group, a vibration detection means detecting vibrations applied to the lens barrel, and a vibration detecting means from the vibration detection means. Detecting an abnormality in the operation of the image stabilization system in a camera with an image stabilization function having a drive means for displacing the correction optical means relative to the lens barrel based on the image stabilization output of the image stabilization system. A camera with an anti-shake function, comprising: an abnormality detecting means for detecting an abnormality; and a function stopping means for stopping the function of the anti-shake system when an abnormality is detected by the abnormality detecting means. 2. The anti-vibration function according to claim 1, wherein the anti-vibration function includes a stopping means for stopping the function of only the means in which the abnormality occurs among the means constituting the anti-vibration system. Comes with a camera. 3. The camera with anti-shake function according to claim 1, further comprising warning means for issuing a warning when an abnormality is detected by the abnormality detection means.