JP2003228093A - Shake detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shake detector capable of accurately detecting camera shake at high speed in the case of detecting the camera shake by utilizing a range-finding sensor. <P>SOLUTION: The shake detector is equipped with a sensor for AF for detecting the vibrating state of a camera, a high contrast part detection means for detecting the high contrast part of subject image data outputted from the sensor for AF at specified time intervals, and a camera shake decision means for deciding whether or not it is the camera shake based on the data variation of the high contrast part of the subject image data detected by the high contrast part detection means. <P>COPYRIGHT: (C)2003,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, in the case of detecting camera shake using a distance measuring sensor, the degree of coincidence of subject image data used for camera shake detection measured at predetermined time intervals is calculated by a general correlation calculation. Not only does it take a long time, but when the distance measuring sensor is a one-dimensional line sensor, it is impossible to detect camera shake in a direction perpendicular to the direction in which the sensors are arranged.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and when camera shake detection is performed using a distance measuring sensor, camera shake detection can be performed at high speed with a short calculation. In addition to being able to perform the above, when the distance measuring sensor is a one-dimensional line sensor, it is also possible to detect camera shake in the direction perpendicular to the direction in which the sensors are arranged. Moreover, it is an object of the present invention to provide a shake detection device capable of performing camera shake detection with high accuracy.

[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. High-contrast part detecting means for detecting a high-contrast part of the image data, and whether the camera shake is caused by the amount of data change of the high-contrast part of the subject image data detected by the high-contrast part detecting means There is provided a camera shake detection device comprising: a camera shake determination unit for determining whether or not the camera shake determination device is provided.

Further, according to the present invention, in order to solve the above-mentioned problems, (2) the high contrast portion of the subject image data detected by the high contrast portion detecting means is the adjacent data of the subject image data. Is the portion with the largest difference, and the camera shake determination means, based on the change amount of the maximum adjacent difference, which is the difference data of the portion,
There is provided the blur detection device according to (1), wherein it is determined whether or not the camera shake.

According to the present invention, in order to solve the above-mentioned problems, (3) the high contrast portion of the subject image data detected by the high contrast portion detecting means is the adjacent data of the subject image data. Is the largest difference, and the camera shake determination means determines the maximum adjacent difference, which is the difference data of the part, between the maximum value of the subject image data or the maximum value and the minimum value of the subject image data. A blur detection device according to (1) is provided, which determines whether or not the camera shake is based on a variation amount of data normalized by a difference.

Further, according to the present invention, in order to solve the above problems, (4) the high contrast part of the object image data detected by the high contrast part detecting means is the adjacent data of the object image data. Is the portion where the difference is the largest, the high-contrast portion detecting means measures the subject image data at predetermined time intervals, and when detecting the maximum adjacent difference which is the difference data of the portion,
The maximum difference position where the difference between the adjacent data in the subject image data is the largest is detected from the subject image data measured for the first time, and the adjacent difference of the maximum difference position is detected for the second time and thereafter, and the camera shake determination is performed. The blur detecting device according to (1) is characterized in that the means determines whether or not the camera shake is based on the amount of change in the adjacent difference detected by the high contrast part detecting means.

According to the present invention, in order to solve the above-mentioned problems, (5) the high contrast portion of the subject image data detected by the high contrast portion detecting means is the adjacent data of the subject image data. Is a predetermined region including a portion having the largest difference, and the camera shake determination unit is configured to detect the data of each sensor in the predetermined region of the subject image data measured at a predetermined time interval by the high contrast portion detection unit. It is characterized in that it is determined whether or not the camera shake is based on the sum of the amounts of change (1).
A blur detection device as described is provided.

[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 which 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. 13 use the light-shielding pattern displayed when the panoramic photography is set.

That is, first, as shown in the screen A, only the upper region is shielded from light, then, as shown in the screen B, only the central region showing the photographing range at the time of panoramic photographing is shielded, and finally the screen C. In this pattern, only the lower area of the panorama light shielding area is sequentially and repeatedly shielded as shown in FIG.

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 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. 14B, the subject can be monitored.

Further, FIG. 15 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. 15 uses the light-shielding portion displayed at the time of setting the panoramic shooting, similarly to the pattern described in 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.

A general user is often unconscious of such a minute vibration causing an effect of “blur” at the time of photographing, and the camera 10 detects this minute vibration and the operation 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 annoying when 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.

When the user sets the camera in this mode and holds the camera and the holding check is unstable, the LCD in the finder 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 views 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.

To supplement 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 hold the camera while holding it while shaking, and unlike the case of FIG. 7A, the change in the image is small, and in fact, even if the image is taken with this, the focus will not change. Depending on the distance, there are many cases where you can take pictures without problems.

In other words, 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 the 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 of the two detection methods, that is, 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, which is equipped with the sensors of the 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 that protects the front lens is opened, the user first performs 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 in 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 a user holds the camera, the holding warning is not displayed for a predetermined time. It is prohibited (step S2).

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

As a result, 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 the 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. A warning different from the warning (step S27) when an AF sensor described later is also used may be provided by only blinking the LED 11.

If the image signal has high brightness and high contrast and is suitable for camera shake determination, the image detection is repeated at predetermined time intervals in the flow from step S20 (steps S22 and S23). The maximum value DM (n) of the adjacent data difference between the detected image signals is obtained each time the steps are performed (steps S21 and S24).

Here, the maximum adjacent data difference is obtained by
When camera shake occurs and the image signal changes, the signal changes remarkably appear because it is a portion where the contrast is high in the image signal, that is, a portion where a difference between adjacent data is large.

That is, by using only the data of the portion where the signal change is large as described above, the S / N in the camera shake detection is improved, and the camera shake detection can be performed with high accuracy.

Next, the difference (blurred data) B = | DM (n-1) between the maximum adjacent data difference DM (n-1) previously obtained in step S25 and the maximum adjacent data difference DM (n) obtained this time. -DM (n) | (1) is calculated, and if the blur data B is larger than the predetermined level Bc, a determination is made in step S26, and the process branches to step S27 to issue a warning that holding is insufficient. To do.

With these warnings, the user recognizes that he / she is unconsciously shaking, and can take countermeasures by holding with both hands or putting it on something.

The blur data B is B in step S26.
If it is larger than Bcc and larger than c, it is considered that the user has taken a completely different angle or changed the composition, and therefore the process returns to step S1 (step S27: Y).

When the image signal is stable, step S26 is branched to N, so that the release operation becomes possible, and thereafter, the exposure sequence from step S30 onward is entered.

First, in step S30, focusing and distance measurement therefor are performed, the exposure time is determined by the luminance information obtained by the image detection in step S3, and exposure is started and counting is started in step S31. (Step S32).

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.

When the acceleration g is large, the camera shake photograph is obtained even when the exposure time is short, and when the acceleration g is small and the exposure time is long, the camera shake photograph is also obtained.

In order to judge this, in step S34, the end of the exposure time is judged, and when the exposure is ended (step S35), the speed is calculated from the calculated acceleration g and the exposure time tEND. Since the amount of movement can be calculated from the fact that it has changed over time, if the amount of movement exceeds the allowable amount ΔY of the lens, the process branches from step S36 to step S37 to issue a warning.

As described above, only the change in speed can be known only by the acceleration sensor, but in the present embodiment, first, the fact that the vehicle is stopped at a predetermined position is output from the AF sensor (image signal).
Is determined by not changing, so that it is possible to accurately determine how much the camera moved during exposure with this as a reference.

Next, the maximum adjacent difference detection in steps S21 and S24 will be described in more detail with reference to the flowchart in FIG.

FIG. 16 is a flow chart showing the procedure for detecting the maximum adjacent difference in the first embodiment.

First, in step S101, integration is performed by the AF sensor, the image signal output from the AF sensor is A / D converted, and image detection is performed.

Next, in step S102, the No. of each sensor constituting the AF sensor is determined. Initialize the variable m that indicates the maximum adjacency difference DM (n).

Next, in step S103, the adjacent difference DS between the mth sensor data and the m + 1th sensor data is calculated.

Next, in step S104, step S
The adjacent difference DS obtained in 103 is compared with the maximum adjacent difference DM (n), and if the adjacent difference DS is larger, step S10.
5, the process proceeds to step S106 if it is smaller.

Next, in step S105, the value of the maximum adjacent difference DM (n) is replaced with the value of the adjacent difference DS.

Next, in step S106, the sensor N
o. Increment m.

Next, in step S107, the sensor N
o. When the value of m reaches -1 which is the number of sensors used for camera shake detection, the maximum adjacent difference detection is terminated and the process returns to the camera sequence of FIG. 12, otherwise, step S
Return to 103.

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

Further, according to the present embodiment, since the camera shake detection is performed based on the change amount of the maximum adjacent difference of the subject image signal, the correlation generally used in the camera shake detection using the AF sensor. Since the calculation does not take time unlike the calculation, the camera shake detection can be performed at high speed and with high accuracy.

Further, according to this embodiment, not only the dark scene and the low contrast scene can be dealt with by detecting the shaking in the X direction and the Y direction by using together with the signal of the acceleration sensor, but also the stationary detection sensor. It is possible to accurately calculate the movement amount of the camera from the output of the acceleration sensor.

With these, 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.

Further, it is needless to say that if the position of the photographing lens is corrected by the calculated amount of movement, it can be applied to a camera with an anti-vibration function (second embodiment). Then
While the maximum adjacent difference DM (n) is used for making the camera shake determination, in the second embodiment, the maximum adjacent difference DM (n) is detected by the procedure shown in FIG. The camera shake determination is performed by using the data normalized by the data corresponding to the contrast of the entire signal.

That is, in the second embodiment, the maximum value in the image signal is MAX (n) and the minimum value is MIN (n).
Then, the blur data B is B = | DM (n−1) / MAX (n−1) −MIN (n−1)) − DM (n) / (MAX (n) −MIN (n)) | As (2), camera shake determination is performed.

Further, when normalizing the maximum adjacent difference DM (n), B = | DM (n-1) / MAX (n-1) is obtained by using only the maximum value MAX (n) in the image signal. The camera shake determination may be performed as −DM (n) / MAX (n) | (3).

Here, the reason why the maximum adjacent difference DM (n) is normalized by the data according to the contrast of the entire image signal is that the camera shake does not occur due to the change of the brightness of the subject, the variation of the integration time and the like. Nevertheless, the maximum adjacency difference DM
This is to prevent the camera shake detection error from increasing due to the change of the value of (n).

FIG. 17 is a flow chart showing the procedure for detecting the maximum adjacent difference according to the second embodiment.

First, in step S201, integration is performed by the AF sensor, the image signal output from the AF sensor is A / D converted, and image detection is performed.

Next, in step S202, the No. of each sensor forming the AF sensor is determined. , A maximum adjacent difference DM (n), a maximum value MAX (n) in the image signal, and a minimum value MIN (n) are initialized.

The initial value of MIN (n) is 255 because it is premised that the resolution of A / D conversion is 8 bits. If the resolution of A / D conversion changes, this The value also changes.

Next, in step S203, the adjacent difference DS between the mth sensor data and the m + 1th sensor data is calculated.

Next, in step S204, step S
The adjacent difference DS obtained in 203 is compared with the maximum adjacent difference DM (n), and if the adjacent difference DS is larger, step S20.
5, the process proceeds to step S206 if it is smaller.

Next, in step S205, the value of the maximum adjacent difference DM (n) is replaced with the value of the adjacent difference DS.

Next, in step S206, the m-th sensor data SD (n) is compared with the maximum value MAX (n),
If SD (n) is larger, the process proceeds to step S207, and if smaller, the process proceeds to step S208.

Next, in step S207, the maximum value MA
The value of X (n) is replaced with the value of the sensor data SD (n).

Next, in step S208, the minimum value MIN (n) is compared with the m-th sensor data SD (n), and if SD (n) is smaller, step S209.
If it is larger, go to step S210.

Next, in step S209, the minimum value is set to M.
The value of IN (n) is replaced with the value of sensor data SD (n).

Next, in step S210, the sensor N
o. Increment m.

Next, in step S211, the sensor N
o. If the value of m has reached -1 the number of sensors used for camera shake detection, the process proceeds to step S212, and if not, the process returns to step S203.

Next, in step S212, the value of the maximum adjacent difference DM (n) is the maximum value, MAX (n), and the minimum value is MI.
Normalize with N (n).

According to the second embodiment as described above,
More accurate camera shake detection can be performed.

(Third Embodiment) In the above-described first embodiment, the maximum adjacent difference DM (n) is detected every time image detection is performed. In form,
After the second image detection in the procedure as shown in FIG. 18, the sensor No. that gives the maximum adjacent difference DM (n) detected in the first image detection. maximum adjacency difference DM based on max
(N) is calculated.

FIG. 18 is a flow chart showing the procedure for detecting the maximum adjacent difference in the third embodiment.

First, in step S301, integration is performed by the AF sensor, the image signal output from the AF sensor is A / D converted, and image detection is performed.

Next, in step S302, it is determined whether or not the image signal for detecting the maximum adjacent difference DM (n) is based on the first image detection. If it is the first time, the process proceeds to step S303. If it is the second time or later, step S31
Go to 0.

Next, in step S303, the No. And the maximum adjacent difference DM (0) in the first image detection are initialized.

Next, in step S304, the adjacent difference DS between the mth sensor data and the m + 1th sensor data is calculated.

Next, in step S305, step S
The adjacent difference DS obtained in 304 is compared with the maximum adjacent difference DM (0) in the first image detection, and if the adjacent difference DS is larger, the process proceeds to step S306, and if it is smaller, the process proceeds to step S308.

Next, in step S306, the value of the maximum adjacent difference DM (0) in the first image detection is replaced with the value of the adjacent difference DS.

Next, in step S307, the sensor N that gives the maximum adjacent difference DM (0) in the first image detection.
o. max is the current sensor number. Replace with m.

Next, in step S308, the sensor N
o. Increment m.

Next, in step S309, the sensor N
o. When the value of m reaches the number of sensors used for camera-shake detection−1, the maximum adjacent difference detection is not finished and the process returns to the camera sequence of 12, and if not, step S
Return to 304.

Next, in step S310, the sensor N that gives the maximum adjacent difference DM (0) in the first image detection.
o. max is the sensor No. Set to m.

Next, in step S311, the adjacent difference (maximum adjacent difference DM (n)) between the max-th sensor data and the max + 1-th sensor data is calculated.

According to the third embodiment as described above,
Since the detection time of the maximum adjacent difference can be shortened, the camera shake detection can be performed at higher speed.

Further, as a modification of the third embodiment,
Also in the second and subsequent image detections themselves, the sensor No. that gives the maximum adjacent difference DM (n) detected in the first image detection. ma
If the detection is performed only in the peripheral area of x, the image detection time is also shortened, so that the camera shake detection can be performed at higher speed.

(Fourth Embodiment) In the above-described first embodiment, the maximum adjacency difference DM is used to perform the camera shake determination.
While only (n) is used, in the fourth embodiment, not only the maximum adjacent difference DM (n) but also the adjacent difference around the maximum adjacent difference DM (n) is used to perform the camera shake determination. It is a thing.

That is, the adjacent difference between the mth sensor data and the (m + 1) th sensor data in the nth image detection is DS (n, m), and the sensor No. giving the maximum adjacent difference. M
ax. And a is the number of data in a predetermined range on one side used for camera shake determination based on max, shake data B is As a result, camera shake determination is performed.

Here, the maximum adjacent difference and the adjacent difference in the vicinity thereof are used. When the contrast of the object is not so high, the value of the maximum adjacent difference is small. This is because the contrast in the camera shake determination range is increased in total by using the adjacent difference around the maximum adjacent difference, and the camera shake detection accuracy is improved.

Then, as a modification of the fourth embodiment, as shown in the equation (5), instead of obtaining the sum of the adjacent differences, the difference between the data offset by a predetermined sensor is obtained to determine the camera shake. The same effect can be obtained by performing the above.

B = || DS (n-1, max-a) -DS (n-1, max + a) |-| DS (n, max-a) -DS (n, max + a) || (5) According to the fourth embodiment as described above, highly accurate camera shake detection can be performed even when the contrast of the subject is not so high.

[0189]

As described above, according to the present invention, when the camera shake detection is performed by using the distance measuring sensor, the camera shake detection can be performed at high speed with a short time calculation. In addition, when the distance measuring sensor is a one-dimensional line sensor, it is also possible to detect camera shake in the vertical direction with respect to the direction in which the sensors are arranged, so that the camera can be operated at high speed and with high accuracy. It is possible to provide a blur detection device capable of performing blur detection.

[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 rigid printed board 14 used in the first embodiment and a flexible printed board (flexible board) 7, and Fig. 1 (c) is a distance measuring optics of the present invention. It is a figure shown in order to demonstrate a 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 of the camera shake warning displayed on D6a.

FIG. 16 is a flowchart showing a procedure of maximum adjacent difference detection according to the first embodiment of the present invention.

FIG. 17 is a flowchart showing a procedure of maximum adjacent difference detection according to the second embodiment of this invention.

FIG. 18 is a flowchart showing a procedure of maximum adjacent difference detection according to the third embodiment of the present invention.

[Explanation of symbols]

14 ... Rigid printed circuit board, 7 ... Flexible printed circuit board (flexible circuit board), 3 ... Monolithic accelerometer (acceleration IC), 10 ... camera, 10a ... barrier, 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.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) G03B 13/36 G02B 7/11 D

Claims (5)

[Claims] 1. An AF sensor for detecting a vibration state of a camera, a high-contrast portion detecting unit for detecting a high-contrast portion of subject image data output from the AF sensor at a predetermined time interval, and the high-contrast portion. Blurring detection means for judging whether or not there is camera shake of the camera based on a data change amount of a high contrast portion of the subject image data detected by a detection means, apparatus. 2. The high-contrast portion of the subject image data detected by the high-contrast portion detecting means is a portion where the difference between adjacent data of the subject image data is the largest, and the hand-shake determining means includes: The blur detection device according to claim 1, wherein it is determined whether or not the camera shake is based on a change amount of a maximum adjacent difference which is difference data of the portion. 3. The high-contrast portion of the subject image data detected by the high-contrast portion detecting means is a portion where the difference between adjacent data of the subject image data is the largest, and the camera shake determination means The maximum adjacent difference that is the difference data of the portion, the maximum value of the subject image data, or
2. The blur detection device according to claim 1, wherein it is determined whether or not the camera shake is based on a variation amount of data normalized by a difference between the maximum value and the minimum value of the subject image data. 4. The high-contrast portion of the subject image data detected by the high-contrast portion detecting means is a portion where the difference between the adjacent data of the subject image data is the largest, and the high-contrast portion detecting means is , When measuring the subject image data at a predetermined time interval and detecting the maximum adjacent difference which is the difference data of the portion, the difference between the adjacent data in the subject image data is the highest due to the first measured subject image data. A large maximum difference position is detected, and after the second time,
The adjacent difference at the maximum difference position is detected, and the camera shake determination means determines whether or not the camera shake is based on the amount of change in the adjacent difference detected by the high contrast portion detection means. The blur detection device according to claim 1, characterized in that 5. The high-contrast portion of the subject image data detected by the high-contrast portion detecting means is a predetermined area including a portion having the largest difference between adjacent data of the subject image data, The determination means determines whether or not the camera shake is based on the sum of the amount of change in the data of each sensor in the predetermined area of the subject image data measured by the high contrast portion detection means at predetermined time intervals. The blur detection device according to claim 1, wherein the determination is performed.