JP2003140217A - Shake detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shake detecting device capable of detecting a camera shake at a speed higher than that of the conventional device by shortening the operation time in the case of detecting the camera shake. SOLUTION: This shake detecting device utilizing the AF sensor of a camera for detecting the vibration state of the camera is equipped with a comparison means for comparing subject image data outputted from the AF sensor at specified time intervals, and a shake detection means for detecting a shake according to the image deviation of the subject image data based on the compared result by the comparison means. In the case of detecting the shake by the shake detection means, the positional deviation of the characteristic point of the subject image data is detected as pre-data.

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.

SUMMARY OF THE INVENTION An object of the present invention is to provide a shake detection device which can shorten the calculation time at the time of detecting a shake and can perform a shake detection at a higher speed than before.

[0011]

According to the present invention, in order to solve the above-mentioned problems, (1) in a shake detection device using an AF sensor of a camera for detecting a vibration state of the camera, Comprising: comparing means for comparing the output subject image data at predetermined time intervals; and blur detecting means for performing blur detection based on the image displacement amount of the subject image data based on the comparison result by the comparing means. There is provided a blur detection device characterized by detecting, as blur data, a positional shift amount of a feature point of the subject image data when performing blur detection by means.

According to the present invention, in order to solve the above problems, (2) the characteristic points of the subject image data are:
The maximum or minimum value of the subject image data output from the AF sensor is the maximum or minimum sensor position (1).
The blur detection device described in 1. is provided.

Further, according to the present invention, in order to solve the above-mentioned problems, (3) at the time of the first feature point detection, the position of the feature point is detected from all the data forming the subject image data, and the second and subsequent times are detected. The blur detection device described in (1) is characterized in that when detecting a feature point, the position of the feature point is detected from subject image data in a predetermined range including the first feature point position.

Further, according to the present invention, in order to solve the above-mentioned problems, (4) if the feature point cannot be detected during the second and subsequent feature point detections, all the data constituting the subject image data are extracted. The feature point position is re-detected, and the feature point position is detected from the subject image data in a predetermined range including the re-detected feature point position when the feature point is detected next time or later. The blur detection device is provided.

Further, according to the present invention, in order to solve the above problems, (5) when a maximum value and a minimum value are detected in the object image data output from the AF sensor,
The position of the sensor with the maximum value and the minimum value among them is used as the feature point for blur detection, and the position shift amount of the sensor position with the maximum value and the position of the sensor position with the minimum value The blur detection device according to (1) is characterized in that the average value of the shift amounts is used as blur data.

According to the present invention as described above, when camera shake occurs during shooting, an existing member is used to perform a holding check display in the vicinity of the finder for easy recognition. Even if a user who does not pay attention to the use of the camera, the camera with a holding check function that allows you to take a beautiful photo with little effect of camera shake by carefully holding while looking at the check display This can be realized with a higher precision and a simpler structure, which can contribute to the provision at a low price.

[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.

FIGS. 1 and 2 are views showing an example of the configuration of a camera according to the first embodiment of the present invention.

FIG. 1A is a perspective view showing the external appearance of a camera according to the first embodiment of the present invention 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. 1 (c), 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 received by two light receiving elements. The object distance can be detected from the relative position difference X detected by the lens 5d and the sensor array 5c.

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. 4 (c), an IC with a processing circuit capable of detecting acceleration in a predetermined direction can be obtained by forming an IC chip having this movable electrode structure on a silicon substrate 20. Is composed monolithically.

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. 13 use the light-shielding pattern displayed when the panorama shooting is set. First, as shown in the screen A, only the upper area is shielded, 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. 14 shows an example of a normal display pattern displayed on the in-finder LCD 6a.

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 camera shake does not occur, (a) in FIG. ) Screen D
Alternatively, returning to the screen E of FIG. 14B, the subject can be monitored.

Further, FIG. 15 shows an example of a display pattern of the camera shake warning displayed on the LCD 6a.

The display pattern of the camera shake warning shown in FIG. 15 uses the light-shielding portion displayed at the time of setting the panoramic shooting, as in the pattern described with reference to FIG.

That is, the display pattern of the camera shake warning shown in FIG. 15 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. 15 is different from the pattern shown in FIG. 13, 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.

In addition, since the blinking is performed as described above during the camera shake warning, unlike the normal display in FIGS. 14A and 14B, 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.

In general, 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 this minute vibration, and as shown in 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 6b blinks, it is understood 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.

FIG. 12 is a flow chart for explaining the display control and the like performed by the CPU in the camera with the holding check mode equipped with the sensors of such two detection methods in the sequence according to the built-in program. .

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).

As a result, it is determined whether the image detection is suitable for the holding check. Therefore, in the case of low luminance (step S4) or low contrast (step S5), this is determined and the image signal is not used. Then, the flow for blur determination by acceleration detection is entered (step S10).

Then, when the acceleration sensor outputs a signal and the output of the reverse acceleration 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 (such as in FIG. 13), and as shown in FIG. When only the LED 11 blinks and the AF sensor is also used (step S26)
The warning may be different from.

If the image signal has high brightness and high contrast and is suitable for camera shake determination, step S20,
The detection of the position (Nmax) of the sensor that has output the maximum value of the maximum values of the image signal, which will be described later, is repeated at predetermined time intervals (step S22) in the flow from step S21 (step S22).
23, S24).

Then, the shift amount of the sensor position (| Nm
ax (n) -Nmax (n-1) |) in step S25
If it is above the predetermined level Xc,
The process branches to step S26 to issue a warning that holding is insufficient.

That is, when image signals such as a (n) and b (n) are measured after a predetermined time as shown in FIG. 16, the position of the sensor that outputs the maximum value in each image signal. Amax and BmaX are detected, and Xmax = | A
When max-Bmax | is greater than or equal to Xc, it is determined as camera shake.

By the warning based on such a judgment, the user recognizes that he / she is unconsciously shaking, and he / she can take countermeasures by holding the camera with both hands or putting it on something. it can.

In the above determination, the camera shake determination is performed by the amount of deviation of the position (Nmax) of the sensor that outputs the maximum value of the maximum values of the image signal, but instead of this, the minimum value of the image signal is detected. The camera shake determination may be performed based on the shift amount (Xmin = | Amin−Bmin |) of the position (Nmin) of the sensor that outputs the smallest value among them.

Although the above-mentioned sensor position detection is normally performed using the output of one of the pair of sensor arrays 5c, the output of both sensor arrays may be used.

Further, the amount of deviation of the sensor position is calculated in step S2.
If Xcc is larger than Xc of 5, it is considered that the user has taken a completely different angle or changed the composition. Therefore, the process returns to step S1 (Y of S27).

If the image signal is stable, step S25 is branched to N, so that the release operation becomes possible, and thereafter, the exposure sequence from step S30 is started.

First, focusing and distance measurement therefor are performed, the exposure time is determined by the brightness information obtained by the image detection in step S3, and exposure is started.

During this time, if the camera shakes, camera shake occurs, so acceleration is detected in step S33, 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 S34, and when the exposure is completed (step S35), the speed is calculated from the calculated acceleration g and the exposure time tEND.

Since the movement amount can be calculated from the fact that the speed has changed only for the time tEND by this speed, if it exceeds the lens allowable amount ΔY, the process branches from step S36 to S37 to issue a warning. .

As described above, only the change in velocity can be understood only by the acceleration.

However, in the present embodiment, first, it is determined that the camera is stopped at the predetermined position by the fact that the output (image signal) of the AF sensor does not change. It is possible to accurately determine how much the camera has moved.

FIG. 18 is a flow chart for explaining the procedure of detecting the position (peak position detection) of the sensor that has output the maximum value among the maximum values of the image signal.

First, in step S101, the light receiving lens 5d integrates a subject image signal obtained by photoelectrically converting the subject image formed on the sensor array 5c according to its luminance distribution.

Next, in step S102, the analog output of the subject image signal integrated in the previous step S101 is A / D converted and read as sensor data.

Next, in step S103, the sensor N
o. The counter n is 1, the detection end determination value m is the number of sensors, the maximum value MAX is 0, and the minimum value MIN is 255 (step S1.
(When A / D conversion in 02 is set to 8 bits).

Next, in step S104, the adjacent n
The data D (n), D (n +
The magnitude relationship of 1) is compared, and if D (n) is larger, the process proceeds to step S105, and if D (n + 1) is larger, the process proceeds to step S114.

Next, in step S105, D (n)-
Since (n + 1) ≧ 0, the minus flag f mns
To clear.

Next, in step S106, the sensor N
o. The counter n is incremented to n + 1.

Next, in step S107, the minus flag f It is determined whether mns is 1.

Next, in step S108, adjacent n
The data D (n), D (n +
The magnitude relationship of 1) is compared, and if D (n) is larger, the process proceeds to step S109, and if D (n + 1) is larger, the process proceeds to step S113.

Next, in step S109, D (n)-
Since (n + 1) ≧ 0, the minus flag f mns
To clear.

Next, in step S110, the magnitude relationship between the maximum value MAX and D (n) so far is compared, and D (n) is compared.
Is larger, the process proceeds to step S111, and if smaller, the process proceeds to step S113.

Next, in step S111, the maximum value MA
Set X to D (n).

Next, in step S112, the D (n) sensor No. n is the maximum value sensor number. Set to Nmax.

Next, in step S113, it is determined whether or not the peak position detection has been completed for all the sensors. If n = m-1, the peak position detection is ended, otherwise the process returns to step S106.

Next, in step S114, D (n)-
Since D (n + 1) <0, the minus flag f_mn
Set s.

Next, in step S115, adjacent n
The data D (n), D (n +
The magnitude relationship of 1) is compared, and if D (n) is smaller, the process proceeds to step S116, and if D (n + 1) is smaller, the process proceeds to step S113.

Next, at step S116, since D (n) -D (n + 1) <0, the minus flag f_mn.
Set s.

Next, in step S117, the magnitude relationship between the minimum value MIN and D (n) so far is compared, and D (n) is compared.
Is smaller, the process proceeds to step S118, and if D (n) is larger, the process proceeds to step S113.

Next, in step S118, the minimum value MI
Set D (n) to N.

Next, in step S119, the sensor length No. of D (n). n is the minimum value sensor No. Set to Nmin.

Incidentally, in FIG. 16, a (n) indicates the image signal detected last time.

Further, b (n) shows the image signal detected this time.

Amax is the image signal a previously detected.
In (n), the sensor No. whose output is the maximum value. Is shown.

Bmax is the image signal b detected this time.
In (n), the sensor No. whose output is the maximum value. Is shown.

Amin is the image signal a previously detected.
The sensor No. whose output is the minimum value in (n). Is shown.

Bmin is the image signal b detected this time.
The sensor No. whose output is the minimum value in (n). Is shown.

Further, Xmax represents the image shift amount by the sensor whose output is the maximum value, and Xmax = | Ama
x-Bmax |.

Further, Xmin represents the image shift amount by the sensor whose output is the minimum value, and Xmin = | Ami
n 1 β min |.

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

Further, according to the present embodiment, the signal of the AF sensor and the signal of the acceleration sensor are used in combination, and the X direction and the Y direction are combined.
Not only can a sway in a direction be detected to cope with a dark scene or a low-contrast scene, but it can also be used as a stationary detection sensor to accurately calculate the camera movement amount from the output of the acceleration sensor.

Further, generally, when calculating the shift amount of the image signal, it is general to use a known correlation calculation.

In this case, since it is necessary to add and subtract a huge amount for the correlation calculation, the calculation takes time.

In the present embodiment, since it is only necessary to obtain the maximum sensor position and perform the subtraction once, it is possible to significantly reduce the calculation time as compared with the correlation calculation, and speed up the camera shake determination. It can be performed.

Thus, according to the present embodiment,
Accurate camera shake determination after shooting can be performed according to the focal length and aperture of the shooting lens and the shutter speed during shooting.

It is needless to say that the camera shake determination method according to the present embodiment can be applied to a camera with an anti-vibration function so that the position of the photographing lens can be corrected by the calculated movement amount.

(Second Embodiment) In the second embodiment, the peak position detection is performed by using the data of all the sensors of the sensor array for detecting the peak position in the first embodiment described above. On the other hand, after performing peak position detection once using the data of all the sensors, the sensor position (Amax) of the maximum value of the detected image signal a (n) is included as shown in FIG. The peak position is detected by using the sensor data in a predetermined range (SDmax).

In the above detection, the peak position detection may be performed using the data of the sensor within the predetermined range (SDmin) including the minimum sensor position (Amin) detected in the first peak position detection. .

FIG. 19 is a flow chart for explaining the procedure of position detection (peak position detection) of the sensor that has output the maximum value among the maximum values of the image signal.

First, in step S201, the light receiving lens 5d integrates a subject image signal obtained by photoelectrically converting the subject image formed on the sensor array 5c according to its luminance distribution.

Next, in step S202, the analog output of the subject image signal integrated in step S201 is A / D converted and read as sensor data.

Next, in step S203, the sensor N
o. The counter n is 1, the detection end determination value m is the total number of sensors,
Maximum value MAX is 0, minimum value MIN is 255 (step S
(When A / D conversion in 202 is set to 8 bits).

Next, in step S204, it is determined whether or not the all-sensor detection flag f_all is 0. If it is 0, the process proceeds to step S205, and if it is 1, step S205.
Proceed to 206.

In this case, 1 is set to f_all at the first time and at the time of re-detection, and f_all = 0 otherwise.

Next, in step S205, the sensor N
o. In the counter n, the maximum value sensor No. detected last time. N
Number r of sensors on one side within a predetermined detection range SDmax from max
Is set, and SDmax is set as the detection end judgment value m.
= 2 × r + 1 is set.

Here, when the camera shake determination is performed using the minimum value, the sensor No. In the counter n, the previously detected minimum sensor No. From Nmin to predetermined detection range SDmin
The value obtained by subtracting the number r of sensors on one side of is set.

Next, in step S206, the adjacent n
The data D (n), D (n +
The magnitude relationship of 1) is compared, and if D (n) is larger, the process proceeds to step S207, and if D (n + 1) is larger, the process proceeds to step S219.

Next, in step S207, D (n)-
Since D (n + 1) ≧ 0, the minus flag f_mn
Clear s.

Next, in step S208, the sensor N
o. The counter n is incremented to n + 1.

Next, in step S209, it is determined whether or not the minus flag f_mns is 1. If it is 1, the process proceeds to step S210, and if it is 0, the step S22.
Go to 0.

Next, in step S210, adjacent n
The data D (n), D (n +
The magnitude relationship of 1) is compared. If D (n) is larger, the process proceeds to step S211, and if D (n + 1) is larger, the process proceeds to step S215.

Next, in step S211, D (n)-
Since D (n + 1) ≧ 0, the minus flag f mn
Clear s.

Next, in step S212, the magnitude relationship between the maximum value MAX and D (n) so far is compared, and D (n) is compared.
Is larger, the process proceeds to step S213, and if D (n) is smaller, the process proceeds to step S215.

Next, in step S213, the maximum value MA
Set X to D (n).

Next, at step S214, the sensor No. of D (n). n is the maximum value sensor number. Set to Nmax.

Next, in step S215, it is determined whether or not the peak position detection has been completed for all the sensors to be detected. If n = m-1, the process proceeds to step S216, otherwise returns to step S208. .

Next, in step S216, it is determined whether or not the all-sensor detection flag f_all is 0. If 0, the process proceeds to step S217, and if 1 then step S217.
Proceed to 225.

Next, in step S217, the maximum value MA
It is determined whether X is 0, and if it is 0, step S
If it is not 0, the peak position detection ends.

Here, in the case of performing the camera shake determination using the minimum value, it is determined whether or not the minimum value MIN is 255, and if it is 255, the process proceeds to step S218, and if it is not 255, the peak position is detected. finish.

Next, in step S218, 1 is set in the all-sensor detection flag f_all.

This means that when MAX = 0 in step S216, the maximum value was not detected by the detection within the predetermined detection range SDmax, so it is judged that the photographer has changed the direction of the camera greatly. , F_all = 1 in order to perform re-detection in the entire sensor range.

Next, in step S219, D (n)-
Since D (n + 1) <0, the minus flag f_mn
Set s.

Next, in step S220, adjacent n
The data D (n), D (n +
The magnitude relationship of 1) is compared, and if D (n) is smaller, the process proceeds to step S221, and if D (n + 1) is smaller, the process proceeds to step S215.

Next, in step S221, D (n)-
Since D (n + 1) <0, the minus flag f mn
Set s.

Next, in step S222, the magnitude relationship between the minimum value MIN and D (n) so far is compared, and D (n) is compared.
Is smaller, the process proceeds to step S223, and if D (n) is larger, the process proceeds to step S215.

Next, in step S223, the minimum value MI
Set D (n) to N.

Next, in step S224, the D (n) sensor No. n is the minimum value sensor No. Set to Nmin.

Next, in step S225, the all sensor detection flag f_all is cleared in order to perform the next detection within the predetermined detection range SDmax.

In FIG. 17, a (n) represents the image signal of the entire sensor area.

Further, Amax is the sensor No. which has the maximum output in the image signal a (n) of the entire sensor area. Is shown.

Amin is the sensor signal No. of which the output is the minimum value in the image signal a (n) of the entire sensor area. Is shown.

SDmax indicates the peak position detection range based on the sensor having the maximum output.

SDmin indicates a peak position detection range with the sensor having the minimum output as a reference.

As described above, according to the present embodiment, the detection range is limited in the second and subsequent detections based on the peak position detected in the first peak position detection. The camera shake determination can be performed at a higher speed than in the first embodiment.

(Third Embodiment) In this third embodiment, the maximum value detected in the peak position detection in steps S21 and S24 of the flowchart shown in FIG. 12 in the first embodiment described above. , And the minimum sensor positions Nmax and Nmin are used to perform the camera shake determination. At the time of the camera shake determination in steps S25 and S27, the average value AV of the deviation amounts of Nmax and Nmin.
The determination is made by comparing E with Xc and Xcc.

Here, the average value AVE of the deviation amounts of Nmax and Nmin is expressed by the following equation.

AVE = (| Nmax (n) -Nmax (n-1) | + | Nmin (n) -Nmin (n-1) |) / 2 According to the present embodiment, the maximum value, and Since the camera shake determination is performed based on the minimum two sensor positions, more accurate camera shake determination can be performed.

As described above, according to the present invention, especially in a shooting scene where camera shake is a concern,
If the holding check mode is set, a warning is issued when the camera shakes and the photographer is made to recognize the camera shake, so that it is possible to take a picture without failure due to the camera shake.

Further, according to the present invention, since the sensor used as the conventional distance measuring sensor is effectively used for the camera shake determination at the time of the holding determination, the cost is not increased and the reliability is high. Blur determination can be performed.

Further, according to the present invention, since the camera shake detection calculation is simplified, the camera shake detection can be performed at high speed.

[0218]

Therefore, as described above, according to the present invention, it is possible to provide a shake detection apparatus which can shorten the calculation time at the time of detecting a shake and can perform a shake detection faster than in the past. it can.

[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 a positional relationship between a hard printed board 14 used in the present embodiment and a flexible printed board (hereinafter referred to as a flexible board) 7, and FIG. It is a figure shown in order to demonstrate an 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.

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

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

15 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. 16 is a diagram showing sensor data of a camera according to a second embodiment of the present invention, sensor No. It is a figure which shows the relationship with.

FIG. 17 is a diagram showing sensor data, a sensor No., and a sensor data in the camera according to the second embodiment of the present invention. It is a figure which shows the relationship with.

FIG. 18 is a view for explaining a procedure of position detection (peak position detection) of the sensor that has output the maximum value among the maximum values of the image signal in the camera according to the first embodiment of the present invention. It is a flowchart shown in.

FIG. 19 is a view for explaining the procedure of position detection (peak position detection) of the sensor that has output the maximum value among the maximum values of the image signal in the camera according to the second embodiment of the present invention. It is a flowchart shown in.

[Explanation of symbols]

14 ... Rigid printed circuit board, 7 ... Flexible printed circuit board (flexible circuit board), 3 ... Monolithic accelerometer (acceleration IC), 10 ... camera, 9 ... Shooting lens, 8 ... Strobe, 15 ... Finder objective lens, 1 ... One-chip microcomputer (CPU), 2 ... Interface IC (IFIC), 4 ... Memory (EEPROM), 12 ... Connector, 6 ... Display element (LCD), 5 ... Auto focus (AF) sensor, 13 ... Patterns for communication lines and switches, 11 ... Warning display part, 101 ... Subject, 102 ... image signal, 5d ... Receiving lens, 5c ... Sensor array, 20 ... Silicon substrate (IC chip), 21 ... oxide film, 22 ... Polysilicon layer, 22c ... movable electrode, 24, 25 ... another electrode, 23a, 23b ... Arms of the movable electrode 22c, 29 ... Processing circuit, 32 ... Carrier wave generator (oscillation circuit), 31 ... Y-direction acceleration sensor, 34 ... Demodulation circuit, 36 ... a filter circuit, 37 ... PWM signal generating circuit, 5a ... Auto focus (AF) section, 5b ... Photometric unit, 6a ... LCD 6a in viewfinder, 8a ... main capacitor, 11a ... resistor 11a, Switch ... 13a, 13b, 19 ... Shutter, 18 ... motor, 16 ... rotary blade, 17 ... Photo interrupter, 6b, 6c ... Display segment, 61 ... Finder eyepiece, 65 ... LED for self-timer display, 10a ... a barrier.

Claims (5)

[Claims] 1. A camera for detecting a vibration state of the camera.
In a shake detection device using an F sensor, a comparison unit that compares subject image data output from the AF sensor at predetermined time intervals, and an image shift amount of the subject image data based on a comparison result by the comparison unit. And a blur detecting unit that detects blur by means of the blur detecting device, wherein when performing blur detection by the blur detecting unit, the amount of positional deviation of the feature points of the subject image data is detected as blur data. . 2. The characteristic point of the subject image data is a maximum value of the subject image data output from the AF sensor,
The shake detection device according to claim 1, wherein the minimum value is the position of the sensor having the maximum value or the minimum value among the minimum values. 3. The position of the characteristic point is detected from all the data constituting the subject image data at the time of first detecting the characteristic point,
The blur detection device according to claim 1, wherein when detecting the characteristic points for the second time and thereafter, the positions of the characteristic points are detected from subject image data in a predetermined range including the first characteristic point position. 4. When the feature point cannot be detected during the second or subsequent feature point detection, the position of the feature point is re-detected from all the data forming the subject image data, and the feature point is detected next time or later. The shake detection device according to claim 3, wherein the position of the feature point is detected from subject image data in a predetermined range including the re-detected feature point position. 5. When the maximum value and the minimum value are detected in the subject image data output from the AF sensor, the blurring detection is performed on the position of the sensor having the maximum value and the minimum value among them. 2. The blur data is the average value of the positional deviation amount of the sensor position whose value is the maximum value and the positional deviation amount of the sensor position whose value is the minimum value. Blur detection device.