JP2003315863A - Camera with shake detecting function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera with a shake detecting function capable of improving feeling in the use of the camera and the effect of camera shake warning in the case of detecting camera shake by using a range-finding sensor. <P>SOLUTION: According to one mode of the invention, the camera with a shake detecting function is equipped with an AF sensor for detecting the vibration state of the camera, a 1st shake detecting means for detecting the shake in a 1st shake detecting period according to the image deviation of subject image data by comparing the subject image data outputted from the AF sensor at the intervals of specified time, a 2nd shake detecting means for detecting the shake in a 2nd shake detecting period according to the image deviation of the subject image data by comparing the subject image data outputted from the AF sensor at least before and after exposure period for film, and a control means for switching a camera shake warning decision level in the 1st shake detecting means for detecting the shake in the 1st shake detecting period and the 2nd shake detecting means for detecting the shake in the 2nd shake detecting period. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blur detection device using an AF sensor for detecting a vibration state such as camera shake that occurs when a camera shoots an image. The present invention relates to a blur detection device capable of effectively issuing the warning.

[0002]

2. Description of the Related Art Generally, when taking a picture while holding the camera with a hand, a camera sometimes shakes during exposure, resulting in a failure photograph, that is, a so-called camera shake may occur.

In order to prevent this camera shake, various anti-vibration techniques have been studied.

This anti-vibration technology is divided into two technologies: vibration detection and countermeasures against the detected vibration.

Further, the vibration countermeasure technology is further classified into a warning technology for making the user recognize the vibration state and a technology for preventing image deterioration due to camera shake by driving and controlling the photographing lens.

As a warning technique, the applicant of the present invention has proposed a camera resistant to camera shake by devising a display means in, for example, Japanese Patent Application No. 11-201845.

Also, an example of applying a distance measuring sensor has recently been disclosed in Japanese Unexamined Patent Publication No. 2001-165622.
It is disclosed in Japanese Patent Publication No. 62-276686.

[0008]

However, some general users do not even know what kind of camera shake is, and press the release button deeply without recognizing the necessity of preventing camera shake and take a picture of failure. There are people who do it.

In particular, when a camera is handed to a person in the vicinity to request a release operation in order to take a picture of himself / herself while traveling, the requested person is confused and shown in FIG. 6 (a). In many cases, the camera is moved so much that it is held, which ruins the photos.

Further, when the camera shake detection is performed by using the distance measuring sensor, the camera shake warning determination level is constant if the camera shake warning determination level is constant irrespective of the timing at which the subject image data used for camera shake detection in the camera sequence is acquired. May be uncomfortable to use or the effect of camera shake warning may be weakened.

The present invention has been made in view of the above circumstances, and when camera shake detection is performed using a distance measuring sensor,
If camera shake occurs during shooting, existing members will be used to display a holding check display near the viewfinder for easy recognition, even if a user who does not pay attention to such camera shake uses it. A camera with a holding check function that can contribute to taking stunning images with less influence of camera shake by carefully holding while checking the check display. An object of the present invention is to provide a camera with a camera shake detection function, which can improve the usability of the camera and the effect of camera shake warning when detecting camera shake.

[0012]

According to the present invention, in order to solve the above-mentioned problems, (1) an AF sensor for detecting a vibration state of a camera, and an object output from the AF sensor at a predetermined time interval. Outputting from the AF sensor at least before and after the exposure period to the film and the first blur detection unit that compares the image data and detects the blur in the first blur detection period based on the image shift amount of the subject image data. Second blur detecting means for performing blur detection in the second blur detection period based on the image shift amount of the subject image data, and first blur detecting in the first blur detection period. And the control means for switching the hand-shake warning determination level between the second shake detection means and the second shake detection means for performing the shake detection in the second shake detection period. A camera with a blur detection function is provided.

Further, according to the present invention, in order to solve the above-mentioned problems, (2) the first blur detection means for the first
The blur detection period is a period during which the first release of the camera is on, or a period during which the power of the camera is on, which does not include the period from when the second release of the camera is turned on until the end of exposure, The second camera shake detection period by the second camera shake detection means is a time period from the second release of the camera being turned on to the end of exposure. Provided.

Further, according to the present invention, in order to solve the above-mentioned problems, (3) the control means sets the camera shake warning determination level in the first shake detection period by the first shake detection means to be higher than the hand shake warning determination level. A camera with a shake detection function according to (1) is provided, wherein the camera shake warning determination level in the second shake detection period by the second shake detection means is made stricter.

Further, according to the present invention, in order to solve the above-mentioned problems, (4) the control means, in the strobe off mode and the night view mode, the second blur detection period by the second blur detection means. Than the camera shake warning judgment level of
A camera with a shake detection function according to (1) is provided, wherein the camera shake warning determination level in the first shake detection period by the first shake detection means is made stricter.

Further, according to the present invention, in order to solve the above-mentioned problems, (5) the control means sets a camera shake warning determination level in a second shake detection period by the second shake detection means as an exposure time. According to another aspect of the present invention, there is provided a camera with a shake detection function, which is characterized in that the camera is switched according to the change.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) In the present embodiment, a liquid crystal display means for displaying a photographing range (finder field of view) according to a photographing mode provided in a viewfinder of a camera by a change in light transmittance, and a camera shake. In addition to the distance measuring sensor described above, a monolithic accelerometer is also used for the determination, and a vibration detection unit that detects camera vibration and indicates the occurrence of camera shake is provided. A technique is adopted in which the transmittance of the display area of the display unit is changed in a pattern so that the user can easily recognize the occurrence of camera shake.

The monolithic accelerometer, which is formed on an IC chip, is a device for detecting vibration by utilizing a capacitance change generated between a movable pattern and an immovable pattern. In the above embodiment, for example, the one proposed in Japanese Patent Laid-Open No. 8-178954 can be used.

In the structure of this monolithic accelerometer, both of the above-mentioned patterns are formed by a polysilicon member on a silicon substrate, one electrode is movable and responds to the acceleration, and the other electrode responds to the acceleration. A pair of capacitors are formed in a state where they are stationary.

When acceleration is applied to such a silicon substrate, the capacitance of one capacitor increases and the capacitance of the other capacitor decreases.

A signal processing circuit for converting these differential capacitances into a voltage signal is required, and these movable electrodes, capacitors and signal processing circuit are monolithically formed on the same substrate.

Japanese Patent Application Laid-Open No. 8178054/1990 describes an application for operating a safety device such as a braking system of an automobile or an airbag. It is explained that it has excellent reliability.

In the present embodiment, such a monolithic accelerometer element is effectively arranged and controlled, and while maintaining the above characteristics, the situation peculiar to the camera is taken into consideration, and a highly accurate and effective anti-vibration camera is realized. .

Incidentally, this portion may be constituted by a shock sensor or the like for detecting a shock or the like, instead of the monolithic accelerometer element.

FIG. 1 and FIG. 2 are diagrams showing a configuration example of the camera according to the present embodiment.

FIG. 1A is a perspective view showing the external appearance of the camera of this embodiment and the internal structure with a part thereof cut away.

FIG. 1B is a side view showing the positional relationship between the hard printed circuit board 14 used in this embodiment and a flexible printed circuit board (hereinafter referred to as a flexible circuit board) 7.

FIG. 1C is a view for explaining the distance measuring optical system of the present invention.

FIG. 2A is a block diagram showing the configuration of the control system including the electronic circuit of the camera according to this embodiment.

FIG. 2 (b) is a diagram for explaining directions that can be detected by the monolithic accelerometer 3 of FIG. 2 (a).

As shown in FIG. 1A, on the front surface of the camera 10, in addition to the taking lens 9 and the strobe 8, a finder objective lens 15 and a light receiving lens of a distance measuring section for autofocus are arranged. There is.

Inside the camera 10, the camera 10
An electronic circuit is provided for fully automatic operation.

This electronic circuit includes a rigid printed circuit board 14
The above-mentioned monolithic accelerometer (acceleration IC) 3 mounted above is also included, and FIG.
In part (a) of FIG. 3, it is cut away so that the internal structure can be seen.

In addition to the acceleration IC 3, a one-chip microcomputer (CPU) for controlling the operation of photographing the entire camera is provided on the hard printed circuit board 14.
1 or an interface IC (IFIC) 2 that drives an actuator such as a motor to drive a mechanical system mechanical unit
Has been implemented.

An EEPROM, for example, is provided in the vicinity of the CPU 1 as a memory 4 for storing data for adjusting component variations in the camera assembly process.

FIG. 1B is a diagram showing the relationship between the rigid printed circuit board 14 and the flexible printed circuit board 7 when the main part of the camera 10 shown in FIG.

The rigid printed circuit board 14 is used for the camera 10.
The flexible board 7 is used because it cannot be bent along the curved surface inside the board, and these two boards are connected by the connector 12.

On the flexible substrate 7, (a) of FIG.
As shown in, a display element (LCD) 6 is mounted, and a communication line with the autofocus (AF) sensor 5 and a switch pattern 13 are formed.

The flexible board 7 wraps around to the back surface of the camera 10 and a warning display section 11 as shown in FIG.
A sounding element PCV, a notification element such as an LED, and the like are mounted, the signal output from the CPU 1 is transmitted to the warning display portion 11, and the AF sensor 5 is also configured to transmit and receive the signal.

As shown in FIG. 1C, the AF sensor 5 obtains the distance to the object 101 by using the principle of triangulation. The image signal 102 of the object 101 is supplied to the two light receiving lenses. 5d and the sensor array 5c, and the object distance can be detected from the relative position difference X.

Since the subject generally has a vertical shadow, the two light receiving lenses 5d are arranged in the horizontal direction (X direction) as shown in FIG. 1A, and the sensor array 5c is also in the horizontal direction. Is divided into

As a result, the image shift in the X direction that occurs when there is camera shake in the lateral direction can be detected by the AF sensor 5.

Therefore, as shown in FIG. 2B, the acceleration IC 3 is arranged in a direction in which the shake is detected in the Y direction rather than the X direction so that the detection in both the X and Y directions is complemented by separate sensors. I have to.

Here, the acceleration IC 3 will be described.

FIG. 3 is a diagram showing an example of a manufacturing process of the acceleration IC 3.

First, as shown in FIGS. 3A and 3B, an oxide film 21 is formed on a silicon substrate (IC chip) 20, and a pattern by a resist mask is formed on the oxide film 21.

Next, as shown in FIG. 3C, the exposed portion is removed by etching, and a resist mask is formed, whereby an opening can be formed in an arbitrary portion.

Thereafter, as shown in FIG. 3D, a polysilicon layer 22 is deposited.

Thereafter, as shown in FIG. 3E, the oxide film 21 is selectively removed by wet etching to form a polysilicon layer 22 on the silicon substrate 20 in a bridge structure. It

The polysilicon layer 22 is made conductive by diffusing impurities such as phosphorus.

FIG. 4 is a diagram showing the configuration of each part of the acceleration IC 3 manufactured as described above.

First, the movable electrode 22c having pillars at four corners as shown in FIG. 4B is formed on the silicon substrate 20 by the above-mentioned bridge structure.

Further, as shown in FIG. 4A, another electrode 24, 25 is formed on the silicon substrate 20, and is arranged adjacent to the arm portions 23a, 23b of the movable electrode 22c described above. As a result, the arm portion 23a, the electrode 24, and the arm portion 2
A microcapacitor is formed between 3b and the electrode 25.

Further, as shown in FIG. 4C, an IC chip in which this movable electrode structure is arranged on the silicon substrate 20 is provided with a processing circuit capable of detecting acceleration in a predetermined direction. The IC is monolithic.

That is, as shown in FIG. 4C, the processing circuit 29 is formed on-chip on the IC chip together with the monolithic movable electrode capacitor.

This is to detect a capacitance component that changes by the movable electrode 22c and output a signal according to the acceleration.

The movement of the bridge-shaped movable electrode 22c increases one of the capacitances formed in the two electrodes,
Since the other decreases, the acceleration in the arrow direction shown in FIG. 4B can be detected.

Therefore, when this IC chip is mounted on a camera, the acceleration in the Y direction can be detected as shown in FIG.

FIG. 5A is a block diagram showing a configuration example of the processing circuit 29.

As described above, the arm portion 23a included in the Y-direction acceleration sensor 31 for detecting the movement in the Y-direction,
A capacitance component is formed between 23b and each of the electrode 24 and the electrode 25, and these capacitances are changed by the movement of the arm portions 23a and 23b.

This capacitance change is converted into an electric signal by the processing circuit 29.

This processing circuit 29 demodulates a carrier wave generator (oscillation circuit) 32 that oscillates a carrier wave having a pulse waveform, and demodulates the respective oscillation waveforms that have changed due to the capacitance change of the Y-direction acceleration sensor 31 by full-wave switching rectification. The circuit 34 includes a filter circuit 36 that outputs an acceleration-dependent analog signal, and a PWM signal generation circuit 37 that performs analog PWM conversion.

FIG. 5B is a diagram showing an output waveform from the processing circuit 29.

In this way, the duty ratio of the pulse (half cycle T1 of the output waveform shown in FIG. 5 (b) according to the acceleration is calculated.
And the total period T2) change.

Therefore, the acceleration IC 3 outputs a voltage signal proportional to the acceleration or a pulse width modulation (PWM) signal proportional to the acceleration.

If the CPU 1 that can handle only digital signals demodulates the PWM signal using the built-in counter,
Acceleration can be detected.

For the voltage signal proportional to the acceleration, an adjusting machine having an A / D converter may be used.

If the PWM signal is used, the CPU 1
It is not necessary to mount an A / D converter on.

FIG. 2A shows such an acceleration IC 3
FIG. 3 is a block diagram showing a configuration of a control system including an electronic circuit of a camera on which is mounted.

In this configuration, a CPU 1 for controlling the entire camera, an IFIC 2, a monolithic accelerometer (acceleration IC) 3, a memory (EEPROM) 4 for storing adjustment data, and an autofocus (AF) section 5a. A photometric unit 5b, a liquid crystal display element (LCD) 6 for displaying the setting status of the camera and information relating to shooting,
An in-viewfinder LCD 6a provided in the finder for displaying information related to shooting, a strobe unit 8 including an arc tube for emitting auxiliary light, a main capacitor 8a for charging electric charges for causing the arc tube to emit light, and a zooming function. , A warning display unit 11 including an LED, and a resistor 11a connected in series to the warning display unit 11.
And switches 13a and 13b for starting a photographing sequence of the camera, a motor 18 for driving a photographing lens 9, a shutter 19, a drive mechanism such as film feeding, and a rotary blade 16 rotating in conjunction with the motor 18. , Motor 18
And a photo interrupter 17 that optically detects the hole of the rotating blade 16 that rotates for drive control.

Further, the motor 18 may switch the driving destination by the switching mechanism when driving each driving mechanism such as the photographing lens 9 and the shutter 19, or each driving mechanism may be provided with another motor.

In this structure, the CPU 1 controls the photographing sequence of the camera according to the operating states of the switches 13a and 13b.

That is, according to the output of the monolithic accelerometer 3, in addition to the warning display by the in-view LCD 6a for camera shake warning, the AF section 5 including the distance measuring section for AF at the time of photographing is also provided.
a, a photometric unit 5 for measuring the brightness of the subject for exposure control
IFIC described above by driving b and receiving necessary signals
The motor 18 is controlled via 2.

At this time, the rotation of the motor 18 depends on the rotation of the rotary blade 1.
6, the IFIC 2 waveform-shapes the signal output from the photointerrupter 17 in accordance with the position of the adjustment hole.

Then, the CPU 1 monitors the state of rotation of the motor 18 based on the output signal from the IFIC 2.

Further, auxiliary light is emitted from the strobe unit 8 as needed.

FIG. 13 shows an example of a warning pattern displayed on the in-viewfinder LCD 6a.

As the in-finder LCD 6a, the one used for the screen display in the panorama mode, the blackout display indicating that the shutter has been released, or the like is diverted.

The patterns A and C shown in FIG. 14 use a light-shielding pattern displayed at the time of setting the panoramic photographing. First, as shown in the screen A, only the upper area is shielded from light, and then the screen B is displayed. As shown in the figure, it is a pattern in which light is shielded only in the central region showing the photographing range at the time of panoramic photographing, and finally, only the lower region of the panoramic light-shielded region is shaded as shown in the screen C.

By repeating this display form,
The user looking through the finder can be made aware that camera shake has occurred.

Incidentally, the blackout display can be performed by simultaneously shielding the patterns A, B and C from light.

FIG. 15 shows an example of a normal display pattern displayed on the LCD 6a in the finder.

With such a display, it is possible to express the feeling that the viewfinder screen is swaying. Therefore, when the user re-holds the camera and the camera shake does not occur, (a) of FIG. ) Screen D
Alternatively, returning to the screen E of FIG. 15B, the subject can be monitored.

Further, FIG. 16 shows an example of the display pattern of the camera shake warning displayed on the LCD 6a.

The display pattern of the camera shake warning shown in FIG. 16 uses the light-shielding portion displayed at the time of panorama shooting setting, as in the pattern described with reference to FIG.

That is, the display pattern of the camera shake warning shown in FIG. 16 is a pattern in which the upper and lower light-shielding portions are alternately displayed as the screen A and the screen C.

The display pattern of the camera shake warning shown in FIG. 16 is different from the pattern shown in FIG. 14, and since the central portion of the screen is always visible, the facial expression of the subject may be difficult to see in the panoramic shooting mode. There is no.

Further, since the blinking is performed at the time of the camera shake warning as described above, unlike the normal display in FIGS. 15A and 15B, the user does not misunderstand.

Next, the principle of vibration detection of the camera having such a configuration will be described with reference to FIG.

As shown in FIG. 6A, the user 10
When holding the camera with one hand, there is a tendency to slightly vibrate the camera diagonally, which can be decomposed into movements in the X and Y directions, as shown in FIG. 6B.

A general user is often unconscious of such a minute vibration causing an effect of "blurring" at the time of photographing, and the camera 10 detects the minute vibration and as described with reference to FIG. By performing the display, the user takes a photograph by taking measures to suppress the vibration, such as attaching the left hand 100a to the camera, and therefore, it is possible to take a photograph without failure due to camera shake.

However, it is always troublesome if a warning is given,
High-class users who are fully familiar with the occurrence of camera shake may rather enjoy taking pictures that effectively use camera shake, so this holding check function should be set as one of the shooting modes. Devise so that it can be set only when it is deemed necessary.

That is, as shown in FIG. 8A, the switch 13c and the liquid crystal display unit 6 are provided, and in the normal state, only the functions of the film counter 6a and the like are operated, and the user 100 operates the mode changeover switch 13c. The camera shake mode is set only when the operation is performed as shown in (b) of FIG.

When this mode is set, FIG.
As shown in (b) and (c) of FIG.
When the portion c is displayed and the portion of the display segment 6b blinks, it can be known that the user has entered the holding check mode.

As shown in FIG. 8D, this mode display also serves as a part of the self-timer mode display, so that the layout in the LCD is not burdened.

In this case, the display segments 6b and 6c are
By being arranged on the substrate 6d as shown in FIG. 9, display control can be performed independently of each other.

FIG. 10 is an external view of the camera 10 as seen from the back side.

If the user sets the camera in this mode and the holding check is unstable, the LCD in the viewfinder blinks as described above, and as shown in FIG.
As shown in FIG. 0, the warning may be issued by blinking the warning display section 11 by an LED or the like near the finder eyepiece section 61 of the camera 10.

FIG. 11 is an external view of the camera 10 viewed from the front.

As shown in FIG. 11, the self-timer display LED 65 is made to blink so that the holding of the photographer can be checked when the owner of the camera asks another person to take a photograph. Good.

FIGS. 7A and 7B are diagrams for explaining the difference between the output (image signal) of the AF sensor and the output of the acceleration sensor, which is a feature of the present invention.

However, in this case, it is assumed that the user is causing camera shake having movements in both X and Y direction components, as shown in FIGS. 6 (a) and 6 (b).

As shown in FIG. 7A, the image position X1,
At the moment when the camera moves from the stationary state at time t = t0, t =
At the timing of t1, the acceleration sensor outputs a signal when the camera starts moving.
6. If the camera moves at a constant speed between time t = t2 and t = t6, the acceleration sensor does not output a signal because the acceleration sensor has no acceleration.

Then, when the camera stops again, t
= T7, this time, an output is generated from the acceleration sensor in such a direction as to stop the previous constant velocity motion, and the camera becomes stationary after time t = t8.

As a supplement to this acceleration sensor, the image sensor (AF sensor) of the camera outputs an image signal that keeps changing during constant velocity motion. Therefore, if this output is judged, even if the output of the acceleration sensor is 0, The CPU 1 of the camera can determine that the camera is moving.

Further, as shown in FIG. 7B, an output may be generated from the acceleration sensor even if the image signal hardly changes.

This is a case where the user is trying to fix and hold the camera while shaking, and unlike FIG. 7A, the change in the image is small, and even if the image is taken with this, the focal point is actually small. Depending on the distance, there are many cases where you can take pictures without problems.

That is, even if a large output is generated from the acceleration sensor, the camera may be slightly moving,
Even if the acceleration sensor reacts only occasionally, the camera position may change significantly.

Further, there are some limits to the blur determination by the AF sensor.

For example, in a scene where there is no contrast or where the image is dark and the image cannot be seen, the image sensor (AF sensor) of the camera cannot make a determination because the change in the image is not known.

Further, with the sensor having only one direction of detection as in the present embodiment, the movement or image change of the camera in a direction different from that is not known, and when the camera shakes too much, the AF sensor The position monitored by is deviated and the image changes completely, making it impossible to accurately determine the amount of blur.

Therefore, it is necessary to devise a sensor for properly determining the blur by properly using the sensors according to the two detection methods of the acceleration sensor and the AF sensor.

12 and 13 are shown for explaining display control and the like performed by a CPU in a camera with a holding check mode equipped with a sensor of such two detection methods in a sequence according to a built-in program. It is a flowchart.

For example, in the camera shown in FIG. 11, when the barrier 10a for protecting the front lens is opened, the user first carries out framing and the holding operation has not been started yet. , The determination by the AF sensor is not effective.

Since the AF sensor monitors only a narrow portion of the screen, it is impossible to make a quantitative evaluation for a large camera movement.

Therefore, in step S1, first, the output of the acceleration sensor is determined, and even if there is a shock when the barrier is opened or when the user holds the camera, the holding warning is not displayed for a predetermined time. It is prohibited (step S2).

After that, the image detection using the AF sensor is started (step S3).

With this, it is judged whether or not the result of the image detection is suitable for the holding check.

If the result of the image detection is low luminance (step S4) or low contrast (step S5), it is determined and the image signal is not used, and the flow of the blur determination by acceleration detection is entered ( Step S10).

Then, when the acceleration sensor outputs a signal and the output of the acceleration in the reverse direction is not detected for a predetermined time (steps S11 and S12), a warning is issued (step S13).

As shown in FIG. 7A, this is to determine that the camera continues to move at a constant speed and inform the user that camera shake may occur.

In this state, there is a possibility that the user intends to perform follow shots, and therefore, for example, the LCD in the finder is not blinked (FIG. 14 and the like), and as shown in FIG. When only the LED 11 blinks and the AF sensor is also used (step S27)
The warning may be different from.

During the above operation, the state detection of the first release switch (step S14) and the state detection of the second release switch (step S15) are also performed, and the first release switch is in the on state and the second release switch is in the off state. For example, if the first release switch is in the off state, the release sequence is terminated, and if the second release switch is in the on state, the exposure sequence from step S31 described below is started.

If the image signal has high brightness and high contrast and is suitable for camera shake determination, image detection is performed at predetermined time intervals (step S2
2) Repeatedly (steps S21 and S24), the subject image data D (n) is acquired.

Then, the subject image data obtained in steps S21 and S24 are used as standard data and reference data, respectively, and the subject image data D (0) obtained in step S21 and step S24 are obtained by the correlation calculation described later in step S25. Then, the image shift amount X (n) from the subject image data D (n) acquired this time is obtained, and if there is a difference of a predetermined level Xc or more, it is determined in step S27, and the process branches to step S28. Try to warn you about insufficient holdings.

With these warnings, the user recognizes that he / she is unconsciously causing camera shake, and takes measures to prevent camera shake by holding with both hands or placing the camera on something. Can be taken.

The state of the first release switch is detected during the operation of detecting the image shift amount (step S2).
6) is performed, and if the first release switch is off, the release sequence ends.

The reference data for detecting the image shift amount in step S25 may be detected as the previously obtained subject image data D (n-1).

The difference between the image signals is Xc in step S27.
If it is larger than even larger Xcc, it is considered that the user has taken a completely different angle or changed the composition, and the process returns to step S1 (step S29 branches to Y).

In this case, the reference data is updated by acquiring the reference data for detecting the image shift amount again in the image detection in step S21.

When the image signal is stable, step S29 is branched to N, so that the second release becomes possible. After that, the exposure sequence starts from step S31.

FIG. 21 shows the image shift amount X (n) in the above.
FIG. 6 is a diagram for explaining a window shift method in a correlation calculation for obtaining

That is, as shown in FIGS. 21A and 21B, the AF sensors 5ca and 5cb are composed of a plurality of photoelectric conversion elements.

Then, these AF sensors 5ca, 5c
image signals a1, a2, ... AN, b1, b output from b
2, ... BN are stored in the storage areas 110a, 110b (only the a1, a2, ... AN acquired with a predetermined time difference as described above are stored when the camera shake is detected).

Predetermined ranges (hereinafter referred to as windows) 120a, 12 from the image signal stored in the storage areas 110a, 110b.
The data of 0b is extracted.

In this case, the simplest method for extracting the data of the windows 120a and 120b is to fix the window 120a and shift the window 120b by one sensor.

[0138] This is an example.
The shift amount, the shift method, and the like may be changed during distance measurement and camera shake detection.

The correlation amount F (n) is calculated by the following equation (1) using the pair of extracted window data.

[0140] However, n: shift amount, W: number of data in window, i: data in window No. k: Calculation area top sensor data No. FIG. 22 is a correlation data graph showing the correlation value for each shift value.

That is, the pair of windows 120a, 12
The degree of coincidence of 0b data is highest when F (n) obtained by shifting the window 120b by one sensor is a minimum value (F (n) = Fmin) as shown in FIG. Thus, the shift amount n = nFmin is the relative image shift amount of the subject image.

This image shift amount is used as a camera shake amount X (n) in the X direction at the time of camera shake determination, and AF at the time of distance measurement.
It is used as data for calculating subject distance data.

Next, the exposure sequence after step S31 will be described.

First, focusing and distance measurement therefor are performed, the exposure time is determined by the brightness information obtained by the image detection in step S33, and exposure is started (steps S31, S32, S34).

During this time, if the camera shakes, it causes camera shake, so acceleration is detected in step S35 and acceleration g due to a shock or the like when the release button is pressed is obtained.

If this acceleration g is large, a camera shake photograph will result even if the exposure time is short.

Even if the acceleration g is small, if the exposure time is long, a camera shake photograph is obtained in this case as well.

In order to determine this, the exposure time is counted in step S36, and when the exposure is completed (step S37), the speed is calculated from the calculated acceleration g and the exposure time tEND.

Since the speed has changed for the time of tEND, it is possible to calculate the movement amount. Therefore, if it is determined in step S42 that it exceeds the permissible amount ΔY of the lens, then from step S42. A warning is given by branching to step S43.

As described above, only the change in speed can be known only by the acceleration, but in the present embodiment, first, it is determined that the output <image signal> of the AF sensor does not change that the vehicle is stopped at the predetermined position. Therefore, the amount of movement of the camera during the exposure can be accurately determined based on this.

Before and after the exposure is started, image detection is performed (steps S33 and S38), and the subject image data D (0) and D (1) thus obtained are used for correlation calculation before and after the exposure. Image shift amount X is calculated (step S
39) If the image shift amount X is larger than the determination value Xc2 determined by the lens allowable amount that is stricter than the camera shake determination value Xc1 during the first release, a warning is issued in step S41.

In this embodiment, the camera shake determination during the release sequence has been described, but the camera shake detection and determination during the first release may be performed when the power of the camera is turned on regardless of the release. Good.

As described above, according to the first embodiment of the present invention, since the AF sensor is effectively used,
The added value of the camera can be increased by using the AF sensor not only for distance measurement but also for holding check.

Further, by using together with the signal of the acceleration sensor, it is possible to detect shaking in the X and Y directions to cope with dark scenes and low-contrast scenes, and also to use it as a stationary detection sensor to output the acceleration sensor. Therefore, it is possible to accurately calculate the camera movement amount.

With these, it is possible to accurately determine the camera shake after photographing according to the focal length and aperture of the photographing lens and the shutter speed at the time of photographing.

Further, in the camera shake determination based on the output of the AF sensor, the camera shake determination value during the first release is set to be looser than after the second release, so that the timing for shooting cannot be grasped without the camera shake warning being set. The camera is easy to use because it prevents it from happening.

Further, it is needless to say that if the position of the photographing lens is corrected by the calculated movement amount, it can be applied to a camera with a vibration proof function.

As described above, according to the first embodiment of the present invention, if the holding check mode is set especially in a shooting scene in which camera shake is a concern, a warning is issued when camera shake occurs, and the photographer Since the camera shake is recognized by the camera, it is possible to take a picture without failure due to camera shake.

Furthermore, according to the present embodiment, at the time of holding determination, the sensor used as the conventional AF sensor for distance measurement is effectively used for the camera shake determination, and the AF sensor is used. When performing blur detection, stable image detection can be performed, and accurate blur detection can be performed.

(Second Embodiment) In the second embodiment, the camera shake determination value Xc1 during the first release is
The switch is made according to the mode of the camera.

The release sequence of the second embodiment will be described with reference to the flow charts shown in FIGS. 17 and 18.

That is, in the second embodiment, as in the first embodiment described with reference to FIGS. 12 and 13, in step S5, the image signal has high brightness and high contrast and is suitable for camera shake determination. In this case, the image detection is performed at a predetermined time interval (step S2
2) Repeatedly (steps S21 and S24), if the first release switch is in the ON state before the process of acquiring the subject image data D (n), the shooting mode of the camera is the strobe off mode or the night view. It is detected whether or not the mode is set (step S206).

Then, in the strobe off mode or the night view mode, the camera shake determination value Xc1 during the first release is set as the camera shake determination value Xcoy for long seconds (step S208). Perform camera shake determination.

The camera shake determination value Xcoy for long time is
It is set to a value stricter than the camera shake determination value Xcn in the normal mode and the camera shake determination value Xc2 for the second release.

With this, in the case of a mode such as the strobe off mode or the night view mode where the exposure time is long and camera shake is likely to occur, the user can be more strongly warned of the camera shake than usual.

The processing other than the above in the configuration and processing of the second embodiment is the same as that of the above-described first embodiment, and the description thereof will be omitted here.

Also, the warning method may be switched according to the switching of the camera shake determination value depending on the camera mode.

As described above, according to the second embodiment, in a shooting mode in which camera shake is likely to occur, such as a strobe off mode or a night view mode, the user can hold the camera more firmly than usual or use a tripod. Can warn you that you need it.

(Third Embodiment) In the third embodiment, the camera shake determination value Xc2 after the second release is
The switching is made according to the exposure time.

The release sequence of the third embodiment will be described with reference to the flowcharts shown in FIGS. 19 and 20.

That is, in the third embodiment, as in the first embodiment described with reference to FIGS. 12 and 13,
Image detection before start of exposure and after end of exposure (step S33,
In step S38), the acquired subject image data D
After obtaining the image shift amount X before and after exposure by a correlation calculation or the like using (0) and D (1) (step S39), the exposure time tEND is compared with a predetermined camera shake warning level switching determination value tx ( In step S340), if the exposure time tEND is longer, the camera shake determination value Xcl for long seconds is selected (step S342).

If the exposure time tEND is shorter, the camera shake determination value Xcs for short and long seconds is selected (step S341).

In this case, the camera shake determination value Xcl for long seconds
Is set to a stricter value than the camera shake determination value Xcs for short and long seconds because the camera may move largely during exposure even if the image shift amount before and after exposure is small.

As a result, it is possible to warn the user of the possibility of camera shake occurring when the shutter speed is long.

The processing other than the above in the configuration and processing of the third embodiment is similar to that of the first embodiment described above, and therefore the description thereof is omitted here.

Further, the switching of the camera shake determination value is not limited to the above two steps, and it may be switched in multiple steps or continuously in accordance with the exposure time.

The camera shake determination value Xc1 during the first release may also be switched at the same time according to the exposure time.

As described above, according to the third embodiment, the optimum camera shake warning can be given according to the exposure time.

As described above, according to the present invention,
Especially in shooting scenes where camera shake is a concern, if you set the holding check mode, a warning will be issued when the camera shakes and the photographer will be made aware of the camera shake, which contributes to taking pictures without failure due to camera shake. It becomes possible.

In addition, at the time of holding determination, the sensor used as a conventional distance measuring sensor is also effectively used for camera shake determination, so that highly reliable camera shake determination can be performed without increasing the cost. it can.

Furthermore, when the camera shake is detected in response to the distance measuring sensor, the usability of the camera and the effect of the camera shake warning can be improved.

[0182]

As described above, according to the present invention, when the camera shake is detected by using the distance measuring sensor, when the camera shake occurs at the time of photographing, the existing member is replaced. Even if a user who does not pay attention to such a camera shake uses it, a holding check display is displayed near the viewfinder so that it can be recognized easily. It is a camera with a holding check function that can contribute to taking stunning photographs with little effect on the camera. Especially when using a distance sensor to detect camera shake, the camera has a feeling of use and camera shake warning. It is possible to provide a camera with a camera shake detection function capable of improving the effect of.

[Brief description of drawings]

FIG. 1 (a) is a perspective view showing an external appearance of a camera according to a first embodiment of the present invention and an internal structure with a part thereof cut away, and FIG. [Fig. 1] is a side view showing an arrangement relationship between a hard printed board 14 used in the first embodiment and a flexible printed board (hereinafter referred to as a flexible board) 7, and (c) of Fig. 1 shows the present invention. It is a figure shown in order to demonstrate a ranging optical system.

2 (a) is a block diagram showing a configuration of a control system including an electronic circuit of the camera according to the first embodiment of the present invention, and FIG. 2 (b) is FIG. It is a figure for demonstrating the direction which can be detected by the monolithic accelerometer 3 of (a).

3 is a diagram showing an example of a manufacturing process of the acceleration IC 3 of FIG.

4 is a diagram showing a configuration of each part of an acceleration IC 3 manufactured by the manufacturing process of FIG.

5A is a block diagram showing a configuration example of a processing circuit 29, and FIG. 5B is a diagram showing an output waveform from the processing circuit 29. FIG.

FIG. 6 is a diagram for explaining the principle of vibration detection of the camera according to the first embodiment of the present invention.

7 (a) and 7 (b) are characteristics A of the present invention.
It is a figure shown in order to demonstrate the difference between the output (image signal) of an F sensor, and the output of an acceleration sensor.

FIG. 8 shows a case where the holding check function of the camera according to the first embodiment of the present invention is set in one of the shooting modes and can be set only when the user determines that it is necessary. FIG.

9 is a diagram showing an arrangement example of display segments 6b and 6c of FIGS. 8B and 8C. FIG.

FIG. 10 is an external view of the camera 10 according to the first embodiment of the present invention viewed from the back side.

FIG. 11 is an external view of the camera 10 according to the first embodiment of the present invention viewed from the front.

FIG. 12 is performed by a CPU in a camera with a holding check mode, which is equipped with sensors according to the two detection methods used in the first embodiment of the present invention, in a sequence according to a built-in program. 9 is a flowchart shown for explaining display control and the like.

FIG. 13 is performed by a CPU in a camera with a holding check mode equipped with sensors according to the two detection methods used in the first embodiment of the present invention in a sequence according to a built-in program. 9 is a flowchart shown for explaining display control and the like.

14 is a viewfinder LC in FIG. 2 (a).
It is a figure which shows an example of the warning pattern displayed on D6a.

15 is a viewfinder LC in FIG. 2 (a).
It is a figure which shows an example of the normal display pattern displayed on D6a.

FIG. 16 is a viewfinder LC in FIG. 2 (a).
It is a figure which shows the example of the display [pattern 1] of the camera shake warning displayed on D6a.

FIG. 17 is a flow chart shown for explaining a release sequence of the second embodiment of the present invention.

FIG. 18 is a flowchart shown to explain a release sequence of the second embodiment of the present invention.

FIG. 19 is a flow chart shown for explaining a release sequence of a third embodiment of the present invention.

FIG. 20 is a flow chart shown for explaining a release sequence of a third embodiment of the present invention.

FIG. 21 is a diagram for explaining a window shift method for correlation calculation according to the first embodiment of the present invention.

22 is a correlation data graph showing a correlation value for each shift value in the window shift method of the correlation calculation of FIG. 21.

[Explanation of symbols]

14 ... Hard printed circuit board, 7 ... Flexible printed circuit board (flexible circuit board), 3 ... Monolithic accelerometer (acceleration IC), 10 ... Camera, 9 ... Shooting lens, 8 ... Strobe, 15 ... Viewfinder objective lens, 1 ... One-chip micro Computer (CPU), 2 ... Interface IC (IFIC), 4 ... Memory (EEPROM), 12 ... Connector, 6 ... Display element (LCD), 5 ... Autofocus (AF) sensor, 13 ... Communication line or switch pattern , 11 ... Warning display part, 101 ... Subject, 102 ... Image signal, 5d ... Light receiving lens, 5c ... Sensor array, 20 ... Silicon substrate (IC chip), 21 ... Oxide film, 22 ... Polysilicon layer, 22c ... Movable electrode , 24, 25 ... Other electrodes, 23a, 23b ... Arms of movable electrode 22c, 29 ... Processing circuit, 32 ... Carrier wave generator (oscillation circuit), 31 ... Y direction acceleration sensor, 34 ... Demodulation circuit, 36 ... Filter circuit, 37 ... PWM signal generation circuit, 5a ... Autofocus (AF) section, 5b ... Photometry section , 6a ... In-viewfinder LCD 6a, 8a ... Main capacitor, 11a ... Resistor 11a, Switch ... 13a, 13b, 19 ... Shutter, 18 ... Motor, 16 ... Rotating blade, 17 ... Photointerrupter, 6b, 6c ... Display segment, 61 ... Viewfinder eyepiece, 65 ... Self-timer display LED, 10a ... Barrier, 110a, 110b ... Storage area, 120a, 120b ... Window, 111 ... Time change of integration level of minimum value data in subject image data, 112 ... Subject Time change of integration level of maximum value data in image data, 5c ... An, comparator, 113 ... OR circuit, 114 ... AND circuit, 115 ... Time change of integration level of minimum value data in subject image data, 116 ... Integration level of maximum value data in subject image data Change over time.

Claims (5)

[Claims] 1. An AF sensor for detecting a vibration state of a camera and object image data output from the AF sensor at predetermined time intervals are compared, and a first blur is detected according to an image shift amount of the object image data. The first blur detecting means for detecting blur in the detection period is compared with the subject image data output from the AF sensor at least before and after the exposure period to the film, and the second image is detected by the image shift amount of the subject image data. Second blur detecting means for detecting blur during the blur detecting period, first blur detecting means for detecting blur during the first blur detecting period, and second blur detecting during the second blur detecting period. A camera with a shake detection function, comprising: a control unit that switches the handshake warning determination level in the shake detection unit and the shake detection unit. 2. The first blur detection period by the first blur detection means is a period during which the first release of the camera is turned on or a period from when the second release of the camera is turned on until the end of exposure. It is a period during which the power of the camera is turned on, which is not included, and the second blur detection period by the second blur detection means is a period from the second release of the camera being turned on to the end of exposure. A camera with a blur detection function according to claim 1. 3. The camera shake during the second shake detection period by the second shake detection unit is higher than the shake shake determination level during the first shake detection period by the first shake detection unit. The camera with a blur detection function according to claim 1, wherein the warning determination level is made stricter. 4. The first shake detection means is higher than the camera shake warning determination level during the second shake detection period by the second shake detection means in the strobe off mode and the night view mode. 2. The camera with a blur detection function according to claim 1, wherein the camera shake warning determination level in the first blur detection period is set to be stricter. 5. The blur detection function according to claim 1, wherein the control unit switches a camera shake warning determination level in the second blur detection period by the second blur detection unit according to an exposure time. With camera.