JP2003107552A - Photographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make precise blur correction by reducing the influence of disturbing vibration resulting from focusing driving on the blur correction during exposure. SOLUTION: A device has a focusing driving means which drives an optical system for focusing, an exposure means for exposing an image plane, a vibration detecting means for detecting a blur, a correcting means for correcting the blur, and a blur correction setting means for setting whether the blur correction is made; and the time from the completion of the focusing driving by the focusing driving means to the start of the exposure by the exposure means is varied according to the setting state of the blur correction setting means (#1004 to #1005).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an image pickup apparatus having a focusing drive means for driving focusing of an optical system and having a vibration isolation function.

[0002]

2. Description of the Related Art In the current camera, all the important operations for photographing such as exposure determination and focusing are automated, so that even a person unskilled in the operation of the camera has a very low possibility of photographing failure.

Recently, a system for preventing camera shake applied to a camera has also been studied, and factors causing a photographing error of a photographer have almost disappeared.

Here, a system for preventing camera shake will be briefly described.

The camera shake at the time of photographing is usually a vibration of 1 Hz to 10 Hz as a frequency. Basically, it is possible to take a photograph without image shake even if such a camera shake occurs at the time of shutter release. As an idea, it is necessary to detect the vibration of the camera due to the hand shake and to displace the correction lens according to the detected value.
Therefore, in order to take a photograph in which the image blur does not occur even if the camera shake occurs, firstly, it is necessary to accurately detect the vibration of the camera and secondly to correct the optical axis change due to the camera shake. Become.

To detect this vibration (camera shake), in principle, a shake detection sensor for detecting acceleration, angular acceleration, angular velocity, angular displacement, etc., and its output are appropriately calculated for camera shake correction. This can be performed by mounting a vibration detection device equipped with a calculation unit on a camera. Then, based on this detection information, the correction means for eccentricizing the photographing optical axis is driven to suppress the image blur.

FIG. 6 is an external perspective view of a compact camera having a vibration isolation system, which shows an arrow 42 with respect to the optical axis 41.
It has a function of correcting shake for vertical shake and horizontal shake of the camera indicated by p and 42y.

In the camera body 43, 43a is a release button, 43b is a mode dial (including a main switch), 43c is a retractable strobe, and 43d is a viewfinder window.

FIG. 7 is a perspective view showing the internal structure of the camera shown in FIG. 6, in which 44 is a camera body, 51 is a correction means, 52 is a correction lens, and 53 is a correction lens 52.
8p, 58y direction to freely drive the arrow 42p,
It is a support frame that performs shake correction in the 42y direction, and details will be described later. 45p and 45y are arrows 46p and 46, respectively.
It is a vibration detection device such as an angular velocity meter or an angular accelerometer that detects shake around y.

Outputs of the vibration detection devices 45p and 45y are converted into drive target values of the correction lens in the shake correction optical device 51 via calculation devices 47p and 47y which will be described later, and are converted into coils included in the shake correction optical device 51. Input and correct shake. Incidentally, 54 is a base plate. 56p and 56y are permanent magnets and 510p and 510y are coils, which form a part of the components of the driving device for driving the correction lens 52).

FIG. 8 is a block diagram showing the details of the arithmetic units 47p and 47y. Since these units have the same configuration, only the arithmetic unit 47p will be described in FIG.

The arithmetic unit 47p is surrounded by a one-dot chain line and includes a DC cut filter 48p and a low pass filter 49.
p, an analog / digital conversion circuit (hereinafter referred to as an A / D conversion circuit) 410p, a drive device 419p, and a camera microcomputer 411 indicated by a broken line. Further, the camera microcomputer 411 includes a memory circuit 412p and a differential circuit 4
13p, DC cut filter 414p, integrating circuit 415
p, a storage circuit 416p, a differential circuit 417p, and a PWM duty changing circuit 418p.

Here, a vibration gyro which detects the shake angular velocity of the camera is used as the vibration detecting device 45p, and the vibration gyro is driven in synchronization with turning on of the main switch of the camera to detect the shake angular velocity applied to the camera. To start.

The DC bias component superimposed on the output signal of the vibration detecting device 45p is cut by the DC cut filter 48p composed of an analog circuit. The DC cut filter 48p has a frequency characteristic of cutting a signal having a frequency of 0.1 Hz or less so that the camera shake frequency band of 1 to 10 Hz applied to the camera is not affected. However, like this
If the characteristic of cutting 0.1 Hz or less is taken, it takes about 10 seconds from the input of the shake signal from the vibration detecting device 45p until the DC is completely cut. Therefore, by setting the time constant of the DC cut filter 48p to be small (for example, to have a characteristic of cutting a signal of a frequency of 10 Hz or less) from the time when the main switch of the camera is turned on to, for example, 0.1 seconds. Cut DC in a short time, then increase the time constant (
DC with a characteristic that only cuts frequencies below 0.1 Hz) DC
The cut filter 48p prevents the shake angular velocity signal from deteriorating.

The output signal of the DC cut filter 48p is
The low-pass filter 49p configured by an analog circuit appropriately amplifies according to the resolution of the A / D conversion circuit 410p and cuts high-frequency noise superimposed on the shake angular velocity signal. This is for avoiding a reading error in the sampling of the A / D conversion circuit 410p when the shake angular velocity signal is input to the camera microcomputer 411 due to noise of the shake angular velocity signal. The output signal of the low-pass filter 49p is sampled by the A / D conversion circuit 410p and taken into the camera microcomputer 411.

Although the DC bias component is cut by the DC cut filter 48p, the DC bias component is again superimposed on the shake angular velocity signal by the subsequent amplification of the low pass filter 49p. Therefore, in the camera microcomputer 411. It is necessary to perform the DC cut again.

Therefore, for example, the shake angular velocity signal sampled 0.2 seconds after the camera switch is turned on is stored in the storage circuit 412p, and the differential circuit 413p obtains the difference between the stored value and the shake angular velocity signal to perform DC cut. . Since this operation can only make a rough DC cut (because the shake angular velocity signal stored 0.2 seconds after the main switch of the camera is turned on includes not only the DC component but also the actual shake. ), A DC cut filter 414p composed of a digital filter in the latter stage
Is performing a sufficient DC cut. The time constant of the DC cut filter 414p can also be changed similarly to the analog DC cut filter 48p, and 0.2 seconds after the main switch of the camera is turned on, another 0.2 second is spent to gradually increase the time constant. . Specifically, this DC cut filter 414p has a filter characteristic of cutting a frequency of 10 Hz or less when 0.2 seconds has passed since the main switch was turned on, and thereafter, the frequency cut by the filter is 5 Hz, 1 Hz every 50 msec. 0.5H
z, 0.2Hz.

However, during the above operation, when the photographer half-presses the release button 43a (turns on sw1) to perform photometry and distance measurement, there is a possibility that the photographer may immediately take a picture, which takes time and a time constant. In some cases it may not be desirable to make changes. Therefore, in such a case, changing the time constant is stopped midway according to the shooting conditions. For example, it was found from the photometric results that the shooting shutter speed was 1/60 seconds, and the shooting focal length was 1
When it is 50 mm, the accuracy of vibration isolation is not so required,
The DC cut filter 414p is completed when the time constant is changed to the characteristic of cutting the frequency of 0.5 Hz or less (the time constant change amount is controlled by the product of the shutter speed and the photographing focal length). As a result, the time for changing the time constant can be shortened, and the photo opportunity can be prioritized. Of course, when the shutter speed is faster or the focal length is shorter, the characteristic of the DC cut filter 414p is 1 Hz.
The processing is completed when the time constant is changed to the characteristics for cutting the following frequencies, and when the shutter speed is slow and the focal length is long, photographing is prohibited until the time constant is completely changed.

The integration circuit 415p starts integration of the output signal of the DC cut filter 414p in response to half-pressing of the release button 43a of the camera (turning on of sw1), and converts the angular velocity signal into an angle signal. However, as described above, when the time constant change of the DC cut filter 414p is not completed, the integration operation is not performed until the time constant change is completed. still,
Although not shown in FIG. 7, the integrated angle signal is appropriately amplified by the focal length and subject distance information at that time, and is converted to drive the appropriate amount correction lens 52 according to the shake angle (zoom focus). Therefore, the photographic optical system changes, and the eccentric amount of the optical axis changes with respect to the driving amount of the correction lens 52, so this correction needs to be performed).

Pushing the release button 43a completely (sw2
When the correction lens 52 is turned on), the correction lens 52 starts to be driven according to the shake angle signal, but at this time, it is necessary to take care so that the shake correction operation of the correction lens 52 does not suddenly start. The memory circuit 416p and the differential circuit 417p are provided for this measure. The storage circuit 416p stores the swing angle signal of the integration circuit 415p in synchronization with the release button 43a being pressed completely (sw2 turned on). Differential circuit 417
p determines the difference between the signal of the integration circuit 415p and the signal of the storage circuit 416p. Therefore, the two signal inputs of the differential circuit 417p when the switch sw2 is on are equal, and the drive target value signal to the correction lens 52 of the differential circuit 417p is zero, but thereafter the output is continuously output from zero. (The memory circuit 416p serves to set the integration signal when the switch sw2 is on as the origin). As a result, the correction lens 52 is prevented from being rapidly driven.

The target value signal from the differential circuit 417p is P
It is input to the WM duty change circuit 418p. The coil 510p included in the shake correction optical device 51 (see FIG. 7)
If a voltage or current corresponding to the deflection angle is applied to
The correction lens 52 is driven in accordance with the shake angle, but PWM drive is desirable in order to save drive power consumption of the correction lens 52 and power consumption of the drive transistor of the coil.

Therefore, the PWM duty changing circuit 418
In p, the coil drive duty is changed according to the target value. For example, in PWM with a frequency of 20 KHz,
When the target value of the differential circuit 417p is “2048”, the duty is “0”, when it is “4096”, the duty is “100”, and the duty is divided into equal parts to determine the duty according to the target value. Note that the duty is determined not only by the target value, but also by finely controlling the shooting conditions of the camera at that time (temperature, posture of the camera, state of the power supply) so that accurate shake correction is performed.

The output of the PWM duty changing circuit 418p is input to a driving device 419p including a PWM driver circuit and the coil 510p. As a result, the output is applied to the coil 510p (see FIG. 6) in the drive device 419p, the correction lens 52 is driven, and shake correction is performed. The driving device 419 is turned on in synchronization with turning on of the switch sw2, and is turned off after the exposure of the film is completed. Also, even if the exposure is completed, the release button 43
Integration circuit 4 as long as a is pressed halfway (sw1 is on)
15p continues the integration, and when the switch sw2 is turned on next time, the memory circuit 416p stores the new integrated output again.

When half-pressing the release button 43a is stopped, the integrating circuit 415p stops integrating the output of the DC cut filter 414p and resets the integrating circuit 415p. Reset means emptying all the information that has been integrated so far.

When the main switch is turned off, the vibration detecting device 45
p is turned off, and the image stabilization sequence ends.

When the output signal of the integrating circuit 415p becomes larger than a predetermined value, it is judged that the panning of the camera is performed, and the time constant of the DC cut filter 414p is changed. For example, change the characteristics that cut frequencies of 0.2 Hz or less to the characteristics that cut 1 Hz or less,
The time constant is returned to the original value within a predetermined time. This time constant change amount is also controlled by the magnitude of the output of the integrating circuit 415p. That is, when the output signal exceeds the first threshold value, D
The characteristic of the C-cut filter 414p is set to cut 0.5 Hz or less, and cuts 1 Hz or less when the second threshold is exceeded, and 5 H when the third threshold is exceeded.
The characteristic is to cut z or less.

When the output of the integrating circuit 415p becomes very large, the integrating circuit 415p is reset once to prevent saturation (overflow) in operation.

In FIG. 8, the DC cut filter 414 is used.
Although p is configured to start the operation 0.2 seconds after the main switch is turned on, the operation is not limited to this, and the operation may be started by half-pressing the release button 43a.
In this case, the integrating circuit 415p is operated from the time when the change of the time constant of the DC cut filter is completed.

The integrating circuit 415p also has a release button 4
The operation was started by pressing the switch 3a halfway (sw1 turned on), but the release button 43a was pressed all the way (sw2 turned on).
It may be configured to start the operation more. In this case,
The storage circuit 416p and the differential circuit 417p are not necessary.

In FIG. 8, the DC cut filter 48p and the low-pass filter 49p are provided in the arithmetic unit 47p, but it goes without saying that they may be provided in the vibration detecting unit 45p.

9 to 11 are views showing the details of the correction means 51 and a part of the driving device 419p (the coil 510p, the permanent magnet 56p, etc.) for driving the correction means 51. More specifically, FIG.
Is a front view of these devices, FIG. 10 (a) is a side view seen from the direction of arrow B in FIG. 9, FIG. 10 (b) is a sectional view taken along the line AA of FIG. 9, and FIG. 11 is a perspective view of each device. .

In FIG. 9, the correction lens 52 (see FIG.
As shown in (b), the correction lens 52 includes a support frame 53.
Two lenses 52a and 52b fixed to the main plate 54
(Which constitutes a group of the photographing optical system) and is fixed to the support frame 53.

A yoke 55 made of a ferromagnetic material is attached to the support frame 53, and permanent magnets 56p and 56y made of neodymium or the like are adsorbed and fixed (indicated by a shaded line) on the back surface of the yoke 55 in the figure. Further, the three support shafts 53a radially extending from the support frame 53 are fitted into the long holes 54a provided in the side wall 54b of the main plate 54.

As shown in FIGS. 10 (a) and 11, the support shaft 53a and the elongated hole 54a are fitted in the direction of the optical axis 57 of the correction lens 52 to prevent looseness, but are orthogonal to the optical axis 57. Since the elongated hole 54a extends in the direction in which the support frame 53 moves, the support frame 53 is restricted from moving in the direction of the optical axis 57 with respect to the base plate 54, but can freely move in a plane orthogonal to the optical axis (arrows 58p, 58p, 5
8y, 58r). However, as shown in FIG. 10, since a tension coil spring 59 is hung between the pin 53b on the support frame 53 and the pin 54c on the ground plate, the directions (58p, 5p) are set.
8y, 58r) is elastically regulated.

Coils 510p and 510y are attached to the base plate 54 so as to face the permanent magnets 56p and 56y (partially hidden lines). The arrangement of the yoke 55, the permanent magnet 56p, and the coil 510p is as shown in FIG. 10B (the permanent magnet 56y and the coil 510y have the same arrangement).
When a current is applied to 10p, the support frame 53 is driven in the direction of arrow 58p, and when a current is applied to the coil 510y, the support frame 5 is moved.
3 is driven in the direction of arrow 58y.

The driving amount is the spring constant of the tension coil spring 59 in each direction and the coil 510p,
It is found by the balance between the thrust force generated by the relation between 510y and the permanent magnets 56p, 56y. That is, the coils 510p and 510
The eccentric amount of the correction lens 52 can be controlled based on the amount of current flowing in y.

[0037]

SUMMARY OF THE INVENTION In the vibration isolation system described above, one problem is the accuracy of angular velocity detection of a vibration gyro which is a vibration detection device.

The vibration gyro is an inertial sensor which is small in size and inexpensive in price for the purpose of detecting camera shake, and is suitable for use in consumer equipment. However, there is a problem in that an attempt is made to detect a minute hand-shake angular velocity, which is small, but the sensor becomes an extremely sensitive sensor, and an error is output due to disturbance vibration.

FIG. 12 is a conceptual diagram of a detection sensitivity frequency characteristic of a small vibration gyro, and a Bode diagram 61 shows a frequency 250.
In the vicinity of 62 Hz, from 10 Hz, which is the camera shake band, to 10 H
The sensitivity is nearly 300 times larger than that of z.
Therefore, when a disturbance vibration around 250 Hz occurs, the vibration is amplified 300 times as large as a camera shake, which adversely affects the calculation.

As shown in FIG. 14, the internal structure of the vibration gyro is a tuning fork (8) which is a vibrator 81 composed of a piezoelectric member.
1a is its fixed portion, 81b and 81c are vibrating beams), and electrodes (not shown) are excited in the directions 82by and 82cy of FIG. The deflection 82bp of the vibrating beams 81b and 81c due to the Coriolis force generated in the beams 81b and 81c,
The magnitude of the angular velocity is detected by detecting 82 cp (electrically extracting the strain of the vibrating beams 81b and 81c).

In order to efficiently excite the vibrating beam, the vibration frequencies in the 82by and 82cy directions must be matched with the natural frequencies of the vibrating beams 81b and 81c in that direction. Further, in order to increase the amount of flexure 82bp and 82cp of the vibrating beams 81b and 81c due to the vibration (in the 82by and 82cy directions) and increase the signal output, the natural frequency in the flexure direction is also aligned with the excitation frequency. Is preferred.

However, if the natural frequencies of the vibrations 81b and 81c in the excitation direction and the natural frequencies of the bending directions are made to coincide with each other, there is no vibration detection band. Therefore, the natural frequency in the excitation direction is matched with the desired vibration detection band. And the natural frequency in the bending direction is shifted. This shifted frequency is called the detuning frequency. Here, if the vibrator is a member that is extremely sensitive (large Q) such as crystal, the angular velocity detection sensitivity near this detuning frequency is high. turn into.

As described above, the camera shake range is from 1 to
The frequency is about 10 Hz, and it is necessary to secure the angular velocity detection band of the vibration gyro to 200 Hz or more in order to detect the camera shake with high accuracy.

Therefore, as shown in FIG. 12, there is a variation in sensitivity with a peak of 250 Hz in the angular velocity detection frequency characteristic of the vibration gyro.

Of course, if the natural frequency in the bending direction is changed by changing the thickness of the vibrating beams 81b and 81c in the bending direction, and the detuning frequency is further separated (for example, 1 KHz),
The error output of the vibration gyro due to the disturbance vibration is easy to control, but if it is set in this way, the distortion of the vibrating beams 81b and 81c in the bending direction due to the Coriolis force generated by the excitation is reduced and the angular velocity sensitivity is reduced. .

Therefore, the detuning frequency is set to an optimum value in consideration of the balance between sensitivity and noise.

As described with reference to FIG. 8, the signal of the vibration detecting device (vibration gyro) 45p is integrated by the integrating circuit 415p. Therefore, it seems that in the shake signal in which the signal due to the disturbance of about 250 Hz is superimposed, the disturbance vibration detection signal component is smoothed by the integrating circuit, and only the shake component can be extracted.

However, the vibration detecting device 45p shown in FIG.
Signal is amplified by the low-pass filter 49p to a level at which the camera shake signal can be accurately detected, and when the signal due to the above-mentioned disturbance vibration is generated in a state where the amplification factor is optimally set, the signal before integration by the integration circuit 415p is performed. Is saturated, and the shake component cannot be integrated.

As described with reference to FIG. 8, the low-pass filter 4
The output of 9p is quantized by the A / D conversion circuit 410p and then taken into the camera microcomputer 411. However, if the signal amplification factor of the low-pass filter 49p is low, the gradation of the minute shake does not appear, and the shake with high accuracy is obtained. Correction cannot be done. Therefore, the low-pass filter 49p outputs the vibration detecting means signal from the DC cut filter 48p with a large amplification factor so that the maximum angular velocity (for example, 10 deg / s) generated when the photographer is holding the camera is almost saturated. Although it is amplified, even if the angular velocity of the above-mentioned disturbance vibration is as small as 0.05 deg / s,
The signal is amplified by the frequency characteristic of FIG.
/ S and saturates the low-pass filter 49p.

As a countermeasure against this, the amplification factor of the low-pass filter may be lowered. In that case, although circuit saturation can be prevented, a low camera shake calculation accuracy can always be obtained and sufficient camera shake correction cannot be performed.

The disturbance vibration that actually occurs in the camera is
Examples include changing the focal length of the photographic optical system and driving the lens for focusing. These drives generally drive the lens by transmitting the driving force of a motor through a gear train. The rotation speed of the motor is often about 1500 rpm,
This is 250 Hz when converted into a frequency, which almost coincides with the sensitivity peak 62 of the vibration gyro. Therefore, the signal of the vibration gyro is saturated at the time of changing the focal length or focusing, and shake correction cannot be performed.

For example, in a single-lens reflex camera, the photographer can confirm the effect of shake correction through the taking lens from the state of holding the camera before the exposure and aiming at the subject. At this time, the focusing drive of the lens is performed. If that happens, shake correction will be disabled during that time.

Even in the compact camera, the circuit is saturated because a signal due to disturbance vibration is superposed on the vibration gyro during lens driving for changing the focal length and lens driving for focusing. However, in a compact camera, shake correction is actually performed only during exposure, and it seems that there is no problem even if the circuit that processes the vibration detection output is saturated before that.

However, once the circuit is saturated, for example, about 1 second is required until the circuit stabilizes next time, so that there is a problem that the image cannot be taken immediately after the saturation is resolved. This is because the time constants of the DC cut filter 414p and the integrating circuit 415p of FIG. 8 are large and therefore it takes time from the circuit operation start to the signal stabilization, and as described with reference to FIG. In addition, although the time constant of the DC cut filter 414p can be switched from small to large at the initial stage of circuit operation, and the time constant of the integrating circuit 415p can also be switched, the operation cannot be immediately recovered after the disturbance vibration is eliminated.

Further, depending on the type of the vibration gyro, when a material having a low viscosity such as crystal is used for the vibrator, once the disturbance vibration is applied, the disturbance vibration input is stopped for a while. Outputs an error signal and some circuits continue to saturate during that period.

FIG. 13 shows the measurement results of the relationship between the focusing drive sequence and the gyro signal error (meaning the error of the output signal of the vibration gyro) in the compact camera.
A short time after pressing the release button of the camera (timing 72 in FIG. 13), the focusing drive of the taking lens (focusing drive section 73) is performed, and after the focusing drive ends, the opening drive of the shutter (timing 74) is performed. Performed (exposure section 7
5). Here, a gyro error starts to occur from the start of focusing drive, and the gyro error continues after the focusing drive ends.

Incidentally, in the gyro signal 71, the error becomes large at the start of focusing drive, becomes small after that, and becomes large again at the end of focusing drive, and is approaching convergence. This is because the motor passes the most sensitive frequency (eg, 250 Hz) of the vibration gyro during acceleration at the start of focusing drive, and then passes the most sensitive frequency of the vibration gyro again during motor deceleration at the end of focusing drive. This is because.

As described above, since the vibrating gyro error is a large error for a while even after the focusing drive is completed, the circuit continues to be saturated until just before the exposure, and even if the circuit is no longer saturated, the error continues for a while. There was a problem that stable shake correction could not be performed.

(Object of the Invention) It is an object of the present invention to provide an image pickup apparatus capable of performing accurate shake correction by reducing the influence of disturbance vibration caused by focusing drive on shake correction during exposure. Is.

[0060]

In order to achieve the above object, the inventions described in claims 1 and 2 are focusing drive means for focusing drive of an optical system and exposure for exposing the image plane. An image pickup apparatus comprising: a unit, a vibration detection unit that detects shake, a correction unit that corrects the shake, and a shake correction setting unit that sets whether or not to perform shake correction, wherein the focus drive unit is provided. The photographing apparatus changes the time from the completion of focusing drive to the start of exposure by the exposure means based on the setting state of the shake correction setting means.

The above configuration clearly separates the photographing conditions in which the shake correction accuracy deteriorates due to the focusing drive of the optical system in the usage conditions of the photographing apparatus, and the focusing drive is completed only under such photographing conditions. By changing the time from the start of exposure to the start of exposure, and then performing the exposure after the output of the vibration detection unit stabilizes, there is no discomfort even during normal shooting (exposure start when the shooting conditions are such that the brightness does not require image stabilization). This means that it will prevent the camera from becoming a difficult-to-use camera that will take longer time), and that it is possible to construct an imaging device with high image stabilization accuracy. When the shake correction operation is set and the shake correction operation is performed, the time from the completion of focusing drive to the start of exposure is set longer than when the shake correction operation is not performed.

In order to achieve the above object, the inventions described in claims 3 and 4 are: focusing drive means for driving focusing of the optical system; exposure means for exposing the image plane; and shake detection. And a correction unit for correcting the shake, wherein the time from the completion of the focus drive by the focus drive unit to the start of the shake correction by the correction unit is The image pickup apparatus changes the disturbance vibration generated by driving depending on the size of the noise superimposed on the output of the vibration detection means as noise.

The above configuration clearly separates the shooting conditions in which the shake correction accuracy deteriorates due to the focusing drive of the optical system in the usage conditions of the shooting apparatus, and the focusing drive is completed only under such shooting conditions. By changing the time from the exposure to the start of exposure and performing the exposure after the output of the vibration detection means stabilizes, it is possible to construct an imaging device with high image stabilization accuracy without any discomfort during normal shooting. The details are as follows:
When the noise superimposed on the output of the vibration detecting means is large, the time from the completion of focusing drive to the start of shake correction is set to be longer than when the noise is small.

In order to achieve the above object, the inventions described in claims 5 and 6 are such that a focus driving means for driving the focus of the optical system, an exposure means for exposing the image plane, and a shake detection. And a correction unit that corrects the shake, wherein the time from the completion of focus drive by the focus drive unit to the start of exposure by the exposure unit is an exposure time by the exposure unit. The imaging device is changed according to the above.

The above configuration clearly separates the photographing conditions in which the shake correction accuracy deteriorates due to the focusing drive of the optical system in the usage conditions of the photographing apparatus, and the focusing drive is completed only under such photographing conditions. By changing the time from the exposure to the start of exposure and performing the exposure after the output of the vibration detection means stabilizes, it is possible to construct an imaging device with high image stabilization accuracy without any discomfort during normal shooting. The details are as follows:
When the exposure time is long, the time from the completion of focusing drive to the start of exposure is set longer than when the exposure time is short.

In order to achieve the above object, the inventions described in claims 7 and 8 are: focusing drive means for driving focusing of the optical system; exposure means for exposing the image plane; and variable magnification photographing. A photographing apparatus having an optical system, a vibration detecting unit for detecting shake, and a correcting unit for correcting the shake, wherein a time from completion of focus drive by the focus drive unit to start of exposure by the exposure unit is set. The focal length of the variable magnification photographing optical system is changed.

The above configuration clearly separates the photographing conditions in which the shake correction accuracy deteriorates due to the actual focusing drive of the optical system in the usage conditions of the photographing apparatus, and the focusing drive is completed only under such photographing conditions. By changing the time from the exposure to the start of exposure and performing the exposure after the output of the vibration detection means stabilizes, it is possible to construct an imaging device with high image stabilization accuracy without any discomfort during normal shooting. The details are as follows:
When the focal length of the variable magnification photographing optical system is long, the time from the completion of focusing drive to the start of exposure is set longer than when the focal length is short.

[0068]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail based on the illustrated embodiments.

FIG. 1 is a block diagram showing a main part of a camera according to an embodiment of the present invention, and other constituent elements of the camera are omitted for simplification of description.

In FIG. 1, when the signal from the camera main switch 114 is input to the camera microcomputer 11,
The shooting barrel is extended from the retracted state to the shooting position, and at the same time the lens barrier is opened. At this time, the vibration detection device 1
9 is also activated.

The photographing mode selected by the photographer is inputted to the camera microcomputer 11 from the photographing mode input member 112. The shooting modes include, for example, a sports mode suitable for shooting a moving subject, a portrait mode suitable for capturing a close-up of a person, a macro mode suitable for capturing a close-up of a subject, and a night scene. There is a night view mode suitable for.

The strobe mode input member 111 inputs the strobe mode to the camera microcomputer 11. In strobe mode, a strobe off mode that does not use a strobe, a strobe on mode that forcibly discharges a strobe,
There is a strobe auto mode that controls whether or not the strobe emits light depending on the brightness of the subject, the direction of the light beam, etc. Also, it is possible to decide whether or not to operate the red-eye reduction function when the strobe emits light.

When the photographer operates the image stabilization switch 18 to decide whether or not to perform the shake correction at the time of photographing, the information is input to the camera microcomputer 11. When the photographer operates the zoom operation member 15 after holding the camera, a zoom signal is input to the camera microcomputer 11, and the camera microcomputer 1
1 controls the zoom driving device 16 based on this zoom signal to change the photographing focal length.

After the photographer determines the photographing focal length, he half-presses the release member 113 which is the release button (sw1 is turned on).
3 measures the distance to the subject and sends the information to the camera microcomputer 11. Then, the camera microcomputer 11 controls the AF driving device 115 to drive a part or all of the photographing lens barrel based on the distance measurement information to adjust the focus of the photographing optical system.

At this time, the shake information from the vibration detecting device 19 is also input to the camera microcomputer 11, and it is determined from the shake state whether the camera is handheld or fixed on a tripod or the ground.

The vibration detecting device 19 is used for the release member 11
Although it may be started from the time of half-pressing 3, the vibration detection device 19 has a low shake detection reliability immediately after the start thereof, so in this embodiment, the start is started in synchronization with the turning on of the camera main switch 114. .

Further, the photometric device 12 measures the subject brightness,
The information is output to the camera microcomputer 11. Then, the camera microcomputer 11 receives the information and the film sensitivity and type, the use state of the image stabilization system, the shooting focal length and the brightness of the lens at that time, the shooting mode, the selection of the shake correction, the distance information to the subject, the shake information, and the like. The exposure time is calculated based on the photographing information determined so far, and at the same time, it is determined whether or not the flash device 17 is used.

When the release member 113 is completely pressed (sw2 is turned on), the camera microcomputer 11 controls the correction means 110 based on the signal from the vibration detection device 19 to start the shake correction. After that, the shutter driving device 14 is controlled to expose the film, and the flash device 17 is caused to emit light depending on the situation.

In the camera microcomputer 11, there is provided an image stabilization necessity judgment section 116.

The image-stabilization necessity determining unit 116 is provided in the photometric device 1
Determine whether shake correction is necessary based on the photometric results of the subject from 2, the sensitivity of the film loaded in the camera, the exposure time set by the brightness of the taking lens, and the focal length of the taking optical system. To do.

Specifically, when the exposure time is 1/30 second,
If the focal length is 28 mm, the product of the exposure time and the focal length is less than 1, so “shake correction is not necessary”. Similarly, even if the exposure time is 1/30 seconds, if the focal length is 90 mm, the exposure time and the focal length are Since the product of 1 is 1 or more, it is determined that "shake correction is necessary." When the exposure time is 1/15 seconds and the focal length is 28 mm, the product of the exposure time and the focal length is 1 or more. Even if the focal length is 90 mm, if the exposure time is 1/100 second, the product of the exposure time and the focal length is smaller than 1, so it is determined that “anti-vibration is unnecessary”.

The result of this shake correction necessity determination is used for changing the lens drive mode for focusing as described later, but when it is also determined that shake correction is unnecessary, the image stabilization switch 18 is on. However, it may be configured such that the shake correction is not performed at the time of exposure, or the shake correction is performed but only the lens driving mode for focusing may be changed based on the signal from the image stabilization necessity determination unit 116.

As described above, the error of the vibration gyro which is the vibration detecting device 19 becomes large when the frequency of the disturbance vibration is near the detuning frequency of the vibration gyro. And
The main frequency of lens drive, which is obtained from the number of rotations of the motor during lens focus drive, is often near the detuning frequency of the vibration gyro.

Therefore, when accurate shake detection is required by the vibration gyro, the motor rotation speed for lens focusing drive is lowered to, for example, 12000 rpm. At this time, the frequency of the motor becomes 200 Hz, which deviates from the detuning frequency of 250 Hz described in FIG. 11, and the error of the vibration gyro is drastically reduced.

Of course, the number of rotations of the motor is 15,000 at the normal time.
Since it has fallen to 3/4 compared with rpm, the time for lens focusing drive will increase accordingly, but the time normally spent for focusing drive is about 0.3 seconds, which is about 0. Since it only changes to 4 seconds, it does not hinder the shooting so much, and the vibration isolation accuracy can be improved accordingly.

Further, when shake correction is required, the time from the completion of focusing drive to the exposure sequence is made longer than in the case where shake correction is not required. This is because the influence of the disturbance vibration due to the focusing drive on the vibration detection device is the focusing speed,
This is because the number is decreased by changing the acceleration, but it is because it is desired to perform the exposure from a stable state where there is no influence of the remaining slight signal error.

The time from the completion of the focusing drive to the shift to the exposure sequence may be changed depending on whether or not the shake correction is necessary as described above, or the shake prevention switch 18 is operated in accordance with the operation thereof. When 18 is turned on, the time from completion of focusing drive to shifting to the exposure sequence may be lengthened regardless of whether or not shake correction is necessary.

FIG. 2 is a flow chart showing the operation of the main part of the present invention. In this flow, the image stabilization switch 18 is in the ON state, and the release button is pushed down (sw).
It starts when the focusing drive is started by turning on 2).

In step # 1001, the signal from the image stabilization necessity determination section 116 is read to determine whether shake correction is necessary during exposure. If shake correction is necessary, step # 1002 is performed.
If not, go to step # 1003. In addition,
When shake correction is not required, it may be set to stop performing shake correction during exposure, and shake correction is not necessary.
It may be set to perform shake correction at the time of exposure.

Step # 1 assuming that shake correction is necessary
At 002, the lens driving speed for focusing is set to be slow here. This is to prevent the drive frequency of the motor from overlapping in the vicinity of the detuning frequency of the vibration gyro as described above.
It has been lowered to 0%. Also, when accelerating and decelerating the lens drive, not the rotational vibration of the motor but the impact of starting and stopping the drive of the lens barrel occurs. Therefore, when shake correction is required, the acceleration and deceleration of the lens drive should be slowed down to start the lens drive. The vibration at the end is also reduced.

At the next step # 1003, the lens drive is awaited. When the lens driving is completed, the process proceeds to step # 1004 to determine again whether shake correction is necessary. If necessary, the process proceeds to step # 1005, and if not necessary, the process proceeds to step # 1006.

Step # 1 assuming that shake correction is necessary
When the process proceeds to 005, the process waits for a predetermined time t1 here, and then ends this flow and shifts to the exposure sequence. If it is determined that the shake correction is unnecessary and the process proceeds to step # 1006,
Here, the process waits for a predetermined time t2, and then this flow is ended and the exposure sequence starts.

Note that, for example, the predetermined time t1 is 0.3
Second, the predetermined time t2 is 0.1 second. In this way, when the shake correction is necessary, the time from the completion of focusing drive to the shift to the exposure sequence is changed as compared with the case where the shake correction is unnecessary. As described above, the influence of the disturbance vibration caused by the focusing drive on the vibration detecting device is reduced by changing the focusing speed and the acceleration, but there is no influence of the remaining slight signal error, which is stable. This is because it is desired to perform exposure from the state.

According to the first embodiment described above, the AF driving device 115 for performing the focusing drive, the shutter driving device 14 for exposing the image surface, and the vibration detecting device 1 for detecting the shake.
9, a correction unit 110 that corrects the shake, and a shake correction correction setting unit (the shake prevention switch 18 and the shake prevention necessity determination unit 116) that sets whether or not to perform the shake correction, and the focusing is performed. The time from the completion of driving to the start of exposure is changed based on the setting state of the shake correction setting means. More specifically, the image stabilization switch 18 is turned on, and the image stabilization necessity determination unit 116 has determined that image stabilization is required, and when the image stabilization operation is performed by the correction unit 110, the image stabilization is performed. Compared to when you do not move,
The time from the completion of focusing drive to the start of exposure is set to be long (# 1004 → # 1005 in FIG. 2).

As a result, the exposure is not started while the disturbance vibration due to the motor drive is superposed on the shake detection output, the influence on the shake correction during the exposure can be reduced, and as a result, the shake can be accurately performed. Correction is possible.

(Second Embodiment) In the first embodiment, the time from the completion of focusing drive to the shift to the exposure sequence is changed depending on whether shake correction is necessary. If it is short, even if the error signal is superposed on the signal of the vibration detection device, the image deterioration due to it does not occur.

Therefore, in the second embodiment of the present invention,
The time from the completion of focusing drive to the shift to the exposure sequence is changed according to the exposure time, not the necessity of shake correction.

For example, when the exposure time is shorter than 1/60 seconds, the exposure sequence is moved to the normal time interval, and when the exposure time is longer than that, the time from the completion of focusing drive to the exposure sequence is lengthened. ing.

FIG. 3 is a flow chart showing the operation of the main part of the second embodiment of the present invention for realizing this. This flow shows that the image stabilization switch 18 is in the ON state and the release button It starts when the focus drive is started by pushing it all the way down. The same parts as those in FIG. 1 are designated by the same step numbers. The electrical configuration of the camera is similar to that shown in FIG.

At step # 2001, the output of the photometric device 12, the sensitivity of the loaded film, the brightness of the taking lens and the exposure time set by the setting of the taking mode are read,
When the exposure time is long (for example, longer than 1/45 seconds), the process proceeds to step # 1002, and when it is shorter than that (for example, 1/6).
If it is shorter than 0 seconds), proceed to step # 1003.

If shake correction is required, step # 1002
Go to, and set the lens drive speed for focusing to slow. This is to prevent the drive frequency of the motor from overlapping with the vicinity of the detuning frequency of the vibration gyro as described above. For example, the drive voltage of the motor is lowered to 80%. Also, when accelerating or decelerating the lens drive, not the rotational vibration of the motor but the impact of starting and stopping the drive of the lens barrel occurs. Therefore, when shake correction is required, the acceleration and deceleration of the lens drive should be gentle and the lens drive start, Vibration at the end is also reduced.

At the next step # 1003, the lens drive is on standby until completion. When the lens driving is completed, the process proceeds to step # 2002, the exposure time is determined again, and when the exposure time is long, the process proceeds to step # 1005, where after waiting for a predetermined time t1, this flow is ended and the exposure sequence is started. On the other hand, when the exposure time is short, the process proceeds to step # 1006, and after waiting for a predetermined time t2, this flow is finished and the exposure sequence is started. The predetermined times t1 and t2 are the same as those in the first embodiment.

As described above, when the exposure time is long, the time from the completion of focusing drive to the shift to the exposure sequence is changed as compared with the case where the exposure time is short. This, as mentioned above,
The influence of disturbance vibration due to focusing drive on the vibration detection device is reduced by changing the focusing speed and acceleration, but it is because we want to perform exposure from a stable state without the influence of the slight remaining signal error. is there.

According to the second embodiment, the time from the completion of the focusing drive by the AF focusing drive device 115 to the start of the exposure by the shutter drive device 14 is changed according to the exposure time. When the exposure time is long, the time from the completion of focusing drive to the start of the exposure is set to be longer than when the exposure time is short (# 2002 → # in FIG. 3).
1005).

As a result, the exposure is not started while the disturbance vibration due to the motor drive is superposed on the shake detection output, the influence on the shake correction during the exposure can be reduced, and as a result, the shake can be accurately performed. Correction is possible.

(Third Embodiment) In the first embodiment, the time interval from the completion of focusing to the shift to the exposure sequence is changed depending on whether shake correction is necessary. Is short, even if the error signal is superposed on the signal of the vibration detecting device, the image deterioration due to the error signal does not occur. Further, when the focal length is short, the amount of extension of the photographing lens barrel is small, so that the rigidity of the lens barrel is increased, and the magnitude of disturbance vibration due to lens driving is smaller than when the focal length is long.
Further, when the focal length is short, the focusing drive amount of the lens barrel from the closest distance to infinity is small, so the time required for focusing drive is short, and even if disturbance vibration occurs, it is given to the vibration detection device. Little impact.

Therefore, in the third embodiment of the present invention,
The time interval from the completion of focusing to the shift to the exposure sequence is changed according to the focal length, not the necessity of shake correction.

For example, when the focal length is as short as 50 mm,
The lens is driven at a normal focusing speed, and when the focal length is longer than that, the focusing speed is lowered.

FIG. 4 is a flow chart showing the operation of the main part of the third embodiment of the present invention for realizing this. This flow shows that the image stabilization switch 18 is in the ON state and the release button It starts when the focus drive is started by pushing it all the way down. The same parts as those in FIG. 1 are designated by the same step numbers. The electrical configuration of the camera is similar to that shown in FIG.

In step # 3001, the focal length information is read from the zoom driving device 16. When the focal length is long (for example, longer than 60 mm), the process proceeds to step # 1002, and when it is shorter (for example, shorter than 50 mm). Go to step # 1003.

If shake correction is required, step # 1002
Go to, and set the lens drive speed for focusing to slow. This is to prevent the drive frequency of the motor from overlapping with the vicinity of the detuning frequency of the vibration gyro as described above. For example, the drive voltage of the motor is lowered to 80%. Also, when accelerating or decelerating the lens drive, not the rotational vibration of the motor but the impact of starting and stopping the drive of the lens barrel occurs. Therefore, when shake correction is required, the acceleration and deceleration of the lens drive should be gentle and the lens drive start, Vibration at the end is also reduced.

At the next step # 1003, the process waits until the lens driving is completed. When the lens driving is completed, the process proceeds to step # 3002, the focal length is determined again, and when the focal length is long, the process proceeds to step # 1005, where after waiting for a predetermined time t1, this flow is ended and the exposure sequence is started. On the other hand, when the focal length is short, the process proceeds to step # 1006, where after waiting for a predetermined time t2, this flow is finished and the exposure sequence is started. The predetermined times t1 and t2 are the same as those in the first embodiment.

As described above, when the focal length is long, the time from the completion of focusing drive to the shift to the exposure sequence is changed as compared with the case where the focal length is short. This is because the influence of the disturbance vibration due to the focusing drive on the vibration detecting means is reduced by changing the focusing speed and acceleration, but it is desired to perform the exposure after the influence of the remaining slight signal error is stabilized. Because.

According to the third embodiment, the time from the completion of the focusing drive by the AF focusing drive device 115 to the start of the exposure by the shutter drive device 14 is changed according to the focal length of the variable magnification photographing optical system. I am trying to do it. For more information,
When the focal length of the variable-magnification photographing optical system is long (tele), the time from the completion of focusing drive to the start of exposure is set longer than when the exposure time is short (wide) (# in FIG. 4). 3002 → # 1005).

As a result, the exposure is not started while the disturbance vibration due to the motor drive is superposed on the shake detection output, the influence on the shake correction during the exposure can be reduced, and as a result, the shake can be accurately performed. Correction is possible.

(Fourth Embodiment) In the first embodiment, the time interval from the completion of focusing to the shift to the exposure sequence is changed depending on whether shake correction is necessary. If the noise generated in the vibration gyro is not large, the image deterioration due to it is small.

Therefore, in the fourth embodiment of the present invention,
The time from the completion of focusing to the exposure sequence is changed depending on the magnitude of noise generated in the vibration gyro, not whether or not shake correction is necessary.

Specifically, when the vibration gyro signal input to the camera microcomputer 11 is larger than a predetermined value and the circuit for processing the signal is saturated or may have been saturated, the focusing drive is completed. The time interval from the start to the exposure sequence is lengthened.

FIG. 5 is a flow chart showing the operation of the main part of the fourth embodiment of the present invention for realizing this. This flow shows that the image stabilization switch 18 is in the ON state and the release button It starts when the focus drive is started by pushing it all the way down. The same parts as those in FIGS. 1 and 4 are designated by the same step numbers. The electrical configuration of the camera is similar to that shown in FIG.

In step # 3001, the focal length information is read from the zoom drive device 16. When the focal length is long (for example, longer than 60 mm), the process proceeds to step # 1002, and when it is shorter (for example, shorter than 50 mm). Go to step # 1003.

If shake correction is required, step # 1002
Go to, and set the lens drive speed for focusing to slow. This is to prevent the drive frequency of the motor from overlapping with the vicinity of the detuning frequency of the vibration gyro as described above. For example, the drive voltage of the motor is lowered to 80%. Also, when accelerating or decelerating the lens drive, not the rotational vibration of the motor but the impact of starting and stopping the drive of the lens barrel occurs. Therefore, when shake correction is required, the acceleration and deceleration of the lens drive should be gentle and the lens drive start, Vibration at the end is also reduced.

At the next step # 1003, the process waits until the driving is completed. When the lens driving is completed, the process proceeds to step # 4001 to compare the magnitude of the output signal of the vibration detection device 19 input to the camera microcomputer 11 with a predetermined level, the signal is large, and the signal is processed until now. When there is a possibility that the circuit is saturated, when the circuit is still saturated, or when it is determined that the circuit may be saturated in the future, the process proceeds to step # 1005, where a predetermined value is determined. After waiting the time t1, this flow is ended and the exposure sequence is started. If there is no concern about the saturation of the circuit, the process proceeds to step # 1006, waits for a predetermined time t2, terminates this flow, and shifts to the exposure sequence. The predetermined times t1 and t2 are the same as those in the first embodiment.

As described above, the noise superimposed on the output signal of the vibration detecting device 19 is large, and the circuit for processing the signal is saturated, or there is a risk thereof, or the circuit has been saturated until now. If you doubt the accuracy of the calculated signal,
The time from the completion of focusing drive to the shift to the exposure sequence is changed. As described above, the influence of the disturbance vibration due to the focusing drive on the vibration detecting means is reduced by changing the focusing speed and the acceleration, but the influence of the deterioration of the calculation accuracy due to the remaining noise component is stable. This is because I want to perform exposure after that.

According to the fourth embodiment described above, the time from the completion of the focusing drive by the AF drive device 115 to the start of the shake correction by the correction means 110 is as described above with reference to FIG. The operation of the device 115 changes the size of the noise superimposed on the output of the vibration detection device 19. Specifically, when the noise superimposed on the output signal of the vibration detection device is large, the time from the completion of focusing drive to the start of shake correction is set longer than when the noise is small (# in FIG. 5). 4002 →
# 1005).

As a result, the exposure is not started while the disturbance vibration due to the motor drive is superposed on the shake detection output, the influence on the shake correction during the exposure can be reduced, and as a result, the shake can be accurately performed. Correction is possible.

(Modification) In each of the above embodiments,
Although the case where the invention is applied to a camera is taken as an example, the invention is not limited to this and can be applied to other optical devices.

Further, all of the first to fourth embodiments described above, or a camera or the like in which the respective embodiments are appropriately combined may be used.

[0128]

As described above, according to the present invention,
It is possible to provide an image pickup apparatus capable of performing accurate shake correction by reducing the influence of disturbance vibration caused by focusing drive on shake correction during exposure.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a main part of a camera according to each embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of a main part according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing an operation of a main part according to the second embodiment of the present invention.

FIG. 4 is a flowchart showing an operation of a main part according to the third embodiment of the present invention.

FIG. 5 is a flowchart showing an operation of a main part according to the fourth embodiment of the present invention.

FIG. 6 is a perspective view showing the overall configuration of a camera equipped with a conventional image stabilization system.

FIG. 7 is a perspective view showing an internal configuration of a camera equipped with a conventional image stabilization system.

FIG. 8 is a block diagram showing an electrical configuration of a conventional vibration isolation system.

FIG. 9 is a front view showing a shake correction optical device of a conventional example.

10 is a view seen from the AA cross section and the direction of arrow B in FIG. 9.

FIG. 11 is a perspective view showing a shake correction optical device of a conventional example.

FIG. 12 is a conceptual diagram of frequency characteristics of detection sensitivity of a general vibration detection device.

FIG. 13 is a diagram for explaining a relationship between a lens drive and an output of a general vibration detection device.

FIG. 14 is a perspective view showing a configuration of a vibration gyro that is a vibration detection device.

[Explanation of symbols]

11 camera microcomputer 14 Shutter drive device 16 Zoom drive 19 Vibration detector 110 correction means 115 AF drive device 116 Vibration isolation necessity determination unit

Claims (8)

[Claims] 1. A focusing drive unit for driving a focus of an optical system, an exposure unit for exposing an image surface, a vibration detection unit for detecting a shake, a correction unit for correcting the shake, and a shake correction. And a shake correction setting unit for setting whether or not to perform the setting, wherein the time from the completion of focus driving by the focus driving unit to the start of exposure by the exposure unit is set by the shake correction setting unit. An imaging device characterized by being changed based on a state. 2. The focus drive completion is set when the shake correction setting means is set to perform shake correction, and when the shake correction operation is performed by the correction means, as compared with the case where the shake correction operation is not performed. The photographing apparatus according to claim 1, wherein a time from when the exposure is started to when the exposure is started is lengthened. 3. An image pickup having a focusing drive unit for driving a focus of an optical system, an exposure unit for exposing an image surface, a vibration detection unit for detecting a shake, and a correction unit for correcting the shake. In the device, the disturbance vibration generated by the focusing drive superimposes the time from the completion of the focusing drive by the focusing drive unit to the start of the shake correction by the correction unit as noise on the output of the vibration detection unit. An image pickup apparatus, which is changed according to the magnitude of the noise. 4. When the noise superimposed on the output of the vibration detecting means is large, the time from the completion of the focusing drive to the start of the shake correction is set longer than when the noise is small. The imaging device according to claim 3. 5. An image pickup apparatus comprising: a focus driving unit for driving a focus of an optical system; an exposure unit for exposing an image surface; a vibration detecting unit for detecting shake; and a correcting unit for correcting the shake. An apparatus according to claim 1, wherein the time from the completion of focusing drive by the focusing drive means to the start of exposure by the exposure means is changed according to the exposure time by the exposure means. 6. The photographing apparatus according to claim 5, wherein when the exposure time is long, the time from the completion of the focusing drive to the start of the exposure is made longer than when the exposure time is short. . 7. A focusing drive unit for driving the focus of the optical system, an exposure unit for exposing the image plane, a variable magnification photographing optical system, a vibration detection unit for detecting a shake, and a shake correction. And a correction unit that adjusts the time from the completion of focusing drive by the focusing drive unit to the start of exposure by the exposure unit according to the focal length of the variable magnification imaging optical system. Characteristic imaging device. 8. The time from the completion of the focusing drive to the start of exposure is longer when the focal length of the variable magnification photographing optical system is long than when the focal length is short. The imaging device according to 7.