JP2003344887A - Camera with camera shake detecting function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera with a camera shake detecting function which can be accomplished with more accurate and simple constitution than in the conventional manner, and also, at a low cost, by which a user can take a fine picture with less influence of the camera shake, holding the camera while viewing a checking display for detecting and displaying the camera shake even in the case the camera is used by such a user who does not give consideration to the camera shake. <P>SOLUTION: The camera with the camera shake detecting function 10 is provided with an LCD 6 arranged in a finder and including an in-finder LCD 6a so as to display photographing information, a range finding sensor (AF part 5a) as a camera shake deciding means, besides, a vibration detecting means (a light receiving lens 5d and a sensor array 5c, etc.), for suggesting the occurrence of the camera shake of the camera main body 10A together with a monolithic acceleration meter (acceleration IC) 3, and the camera is controlled by a CPU 1 for controlling the whole camera so that the using extent of the object image data used for the camera shake detection and the camera shake decision value are switched in accordance with the focal distance of a photographic lens in the case of detecting the camera shake based on the image deviation of the object image data obtained by the comparison of the object image data outputted from an AF part 5a at prescribed intervals. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a camera with a camera shake detection function, which is equipped with a camera shake prevention technology for detecting camera shake generated during shooting with a camera and warning the photographer.

[0002]

2. Description of the Related Art In general, when taking a picture while holding the camera by hand, if the camera shakes during exposure when the shutter speed is slow, a photograph often fails. That is, this is due to the occurrence of camera shake.

Therefore, in order to prevent this camera shake, various anti-vibration techniques have been conventionally studied in cameras.

Such anti-vibration technology is generally classified into two technologies, that is, a technology for detecting the vibration of the camera body and a technology for preventing the vibration to be detected. Further, the technology relating to vibration countermeasures is further classified into a warning technology for making a user aware of the vibration state of the camera body and a correction technology for driving and controlling the photographing lens to prevent image deterioration due to camera shake.

As the above-mentioned warning technique among the above-mentioned image stabilization techniques, 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. 11-20145.

Further, an example in which a distance measuring sensor is applied is also disclosed in Japanese Patent Laid-Open No.
No. 001-165622 gazette, or Japanese Examined Japanese Patent Publication No. 62-2
It is disclosed in Japanese Patent No. 7686.

As described above, conventionally, the above-described image stabilization technique is adopted to take a photograph in an optimum state without the influence of camera shake as much as possible, so that a beautiful photograph can be obtained.

[0008]

However, in the conventional camera equipped with the above-mentioned image stabilization technology, general users do not even know what kind of camera shake is, and do not recognize the necessity of preventing camera shake. There are people who press the release button deeply to take a failed photo, especially when they let go of the camera and ask for a release operation to take a picture of themselves on a trip etc. As shown in FIG. 6 (a), the camera 10 was largely moved to hold the image, which often ruined the photograph.

Further, when a user is warned that a hand-shake photograph may be taken, if blur detection is performed with a constant blur determination value regardless of the focal length of the taking lens, the focal length of the taking lens is When shooting on the short focus side, a warning may be issued even if the camera shake is too low to be a camera shake, and the user may feel annoyed.

Therefore, the present invention has been made in view of the above problems. Even if a user who does not pay attention to camera shake is used, the user can hold the camera while watching the check display for detecting and displaying camera shake. An object of the present invention is to provide a camera with a camera shake detection function, which can realize a camera shake detection function that enables taking a beautiful photograph with less influence of camera shake with higher accuracy and a simpler structure than ever before, and at low cost.

Another object of the present invention is to provide a camera with a camera shake detection function which is convenient for the user without giving an unnecessary warning.

[0012]

According to a first aspect of the present invention, there is provided a camera with a camera shake detection function, which has a camera shake detection function for detecting a camera shake using an AF sensor of the camera for detecting a vibration state of a camera body. In the camera, when the subject image data output from the AF sensor is compared at predetermined time intervals and the camera shake detection is performed based on the image shift amount of the subject image data, the camera shakes according to the focal length of the photographing lens. It is characterized in that the range of use of subject image data used for blur detection and the camera shake determination value are switched.

According to a second aspect of the present invention, there is provided a camera with a camera shake detection function according to the first aspect, wherein the camera shake determination value is such that the focal length of the photographing lens is on the short focus side. In this case, the value is set to be gentle in the case of a long focal point and is set to be a strict value in the case of a long focal point.

A camera with a camera shake detection function according to a third aspect of the present invention is the camera with the camera shake detection function according to the first aspect, which is usually used for camera shake detection when the focal length of the photographing lens is equal to or greater than a predetermined focal length. When the contrast in the use range of the subject image data is low, the use range of the subject image data is widened to perform camera shake detection.

A camera with camera shake detection function according to a fourth aspect of the present invention is the camera with a camera shake detection function according to any one of claims 1 to 3, wherein when camera shake detection is performed,
It is characterized in that the display means provided in the camera displays the occurrence of camera shake to warn the user.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First Embodiment: A camera with a camera shake detection function according to an embodiment of the present invention is a liquid crystal that displays a shooting range (viewfinder field) according to a shooting mode provided in a viewfinder of a camera by a change in light transmittance. In addition to the above-mentioned distance measuring sensor as the camera shake determination for the camera shake determination, a monolithic accelerometer is used in combination, and a vibration detecting means for detecting camera vibration and suggesting the occurrence of camera shake is provided, and camera shake has occurred. In this case, a technique is adopted in which the transmittance of the display area of the liquid crystal display means is changed in a pattern to allow the user to easily recognize the occurrence of camera shake.

The monolithic accelerometer, which is formed in the form of an IC chip, is a device for detecting vibration by utilizing a capacitance change generated between a movable pattern and a movable pattern. Japanese Patent Laid-Open No. 8-17
The one proposed in Japanese Patent No. 8954 can be used. Both patterns are formed of a polysilicon member on a silicon substrate, and one electrode is movable and responds to acceleration, while the other electrode is stationary with respect to acceleration. It forms a pair of capacitors. 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 circuits are formed monolithically on the same substrate.

Further, Japanese Patent Application Laid-Open No. 8-178954 describes an application technique for operating a safety device such as a control system of an automobile or an airbag. Although it has been described that the power and reliability are excellent, the present invention
By effectively arranging and controlling such elements and maintaining the above characteristics, the situation peculiar to the camera is added and a highly accurate and effective image stabilizing camera is realized. This portion may be configured by a shock sensor or the like that detects a shock or the like.

1 and 2 show a configuration example of a camera with a camera shake detection function according to a first embodiment of the present invention. FIG. 1A shows an external configuration of a camera with a camera shake detection function according to the present embodiment, and is a perspective view showing the internal structure with a part broken away. FIG. 1B shows the camera according to the present embodiment. FIG. 1 is a configuration diagram showing an arrangement relationship between a hard printed circuit board and a flexible printed circuit board (hereinafter referred to as a flexible printed circuit board) adopted in FIG. 1, and FIG. 1C is an explanatory view showing a distance measuring optical system of the camera of the present embodiment. . FIG. 2 is a block diagram showing an electrical block configuration of the camera of this embodiment. As shown in FIG. 1A, the camera 1 of the present embodiment
0 is mainly composed of the camera body 10A, and on the front surface of the camera body 10A, in addition to the taking lens 9 and the strobe 8,
A finder objective lens 15, a light receiving lens of a distance measuring unit for autofocus, and the like are arranged. This camera body 1
An electronic circuit group for fully automatic operation of the camera 10 is provided inside the 0A. This electronic circuit group also includes the above-described monolithic accelerometer (acceleration IC) 3 mounted on the hard printed board 14, and in order to show the positional relationship, a part of the internal structure is shown in FIG. It is broken as you can see.

In addition to the acceleration IC 3, on the hard printed board 14, a one-chip microcomputer (CP) is provided as a control means for controlling the operation relating to photographing of the entire camera.
U) 1 or an interface IC (IFIC) that drives a mechanical mechanism unit by operating an actuator such as a motor
2 is implemented. Further, in the vicinity of the CPU 1, for example, an EEPROM is provided as a memory 4 for storing adjustment data for component variations in the camera assembly process.

FIG. 1B is a diagram showing the relationship between the rigid printed board 14 and the flexible board 7 when the camera is viewed from the lateral direction. As shown in FIG. 1B, the rigid printed circuit board 14 is not bent along the curved surface inside the camera, so that the flexible printed circuit board 7 is used and is connected by the connector 12.

A display device (LC
D) 6 (see FIG. 1A) 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 body 10A, and an announcement element such as a sounding element PCV or an LED in the warning display section 11 as shown in FIG. 1B is mounted, and the warning display section 11 outputs from the CPU 1. In addition to transmitting the generated signal, the AF sensor 5c is also capable of transmitting and receiving the signal.

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

In this case, since the subject generally has a vertical shadow, the two light-receiving lenses 5d are shown in FIG.
The sensor array 5c is divided in the horizontal direction (X direction) as shown in FIG. With this arrangement, an image shift in the X direction caused by a camera shake in the lateral direction can be detected by this depth.

Therefore, the acceleration IC 3 is as shown in FIG.
As shown in FIG. 7, the sensors are arranged in the Y-direction rather than the X-direction so as to detect blurring, and the detection in both the X and Y directions is complemented by separate sensors.

The acceleration IC 3 will now be described in more detail with reference to FIGS. 3 and 4.

FIG. 3 is an explanatory view showing an example of the manufacturing process of the acceleration IC 3, and FIGS. 3 (a) to 3 (e) correspond to the manufacturing process sequence (first to fifth processes). is there.
4 shows a specific structure of the acceleration IC 3, FIG. 4 (a) is a structural diagram on a silicon substrate, and FIG. 4 (b).
FIG. 4 is a perspective view showing a configuration of a silicon substrate including movable electrodes and arms, and FIG. 4C is a configuration diagram showing an IC configuration including a processing circuit formed on the silicon substrate.

First, an oxide film 21 is formed on a silicon substrate (IC chip) 20 (see FIGS. 3A and 3B), and a pattern is formed on the oxide film 21 by a resist mask and exposed. The part that is being removed is removed by etching,
When a resist mask is used, an opening can be formed in an arbitrary portion (see FIG. 3C).

Then, after depositing a polysilicon layer 22 on the surface (see FIG. 3D), the oxide film 21 is selectively removed by wet etching, whereby the polysilicon layer 22 has a bridge-like structure. Then, it is formed on the silicon substrate 20 (see FIG. 3E). Impurities such as phosphorus are diffused into the polysilicon layer to make it conductive.
Due to this type of bridge structure, the movable electrode 22 having pillars at four corners as shown in FIG. 4B or the silicon substrate 20 is formed.

Also, on the silicon substrate 20, as shown in FIG.
As shown in (a), separate electrodes 24 and 25 are formed and arranged adjacent to the arm portions 23a and 23b of the movable electrode 22 described above, whereby the arm portion 23a, the electrode 24, and the arm portion 23 are formed.
A small capacitor capacitance is formed between b and the electrode 25.
Further, as shown in FIG. 4C, an IC chip having this movable electrode structure arranged on the silicon substrate 20 can be used as a monolithic IC with a processing circuit capable of determining acceleration in a predetermined direction.

That is, as shown in FIG. 4 (c), the processing circuit 29 is formed on the chip together with the movable electrode capacitor composed of the monolithic structure on this chip. This is to detect the amount of capacitance changed by the movable electrode 22 and output a signal corresponding to the acceleration. Due to the movement of the bridge-shaped movable electrode 22, one of the capacitances formed in the two electrodes increases and one force decreases,
The acceleration in the arrow direction in FIG. 4B can be detected.

Therefore, when the IC chip having such a configuration is mounted on the camera, the acceleration in the Y direction can be determined as shown in FIG. 2 (b).

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

As described above, a capacitance component is formed between each of the arm portions 23a and 23b included in the Y sensor 31 for detecting the movement in the Y direction and the electrode 24 and the electrode 25, and the arm portion 23a, The movement of 23b changes these capacities. This capacitance change is converted into an electric signal by the processing circuit 29.

As shown in FIG. 5A, the processing circuit 29 includes a carrier wave generator (oscillation circuit) 32 for oscillating a carrier wave having a pulse waveform, and the respective oscillations which are changed by the capacitance change of the Y-direction acceleration sensor 31. A demodulation circuit 34 for demodulating the waveform by full-wave switching rectification, a filter circuit 36 for outputting an acceleration-dependent analog signal, and an analog-
It is composed of a PWM signal generation circuit 37 that performs PWM conversion.

FIG. 5B shows an output waveform of the processing circuit 29. As shown in this figure, the output of the processing circuit 29 is the duty ratio of the pulse (T
The ratio of 1 to T2) changes.

Therefore, the acceleration IC 3 outputs a voltage signal proportional to the acceleration or a pulse width modulation (PWM) signal proportional to the acceleration. The CPU 1 that can handle only digital signals can detect acceleration by demodulating a PWM signal using a built-in counter. For the voltage signal proportional to the acceleration, a regulator 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 a block circuit diagram of a camera in which such an acceleration IC 3 is mounted, and the configuration of the main components will be described with reference to this figure.

The electric circuit configuration of the camera 10 of this embodiment is, as shown in FIG. 2A, a CPU 1 for controlling the entire camera, an IFIC 2, and a monolithic accelerometer (acceleration IC) 3. , A memory (EEPROM) 4 for storing adjustment data, an autofocus (AF) section 5a, a photometric section 5b, a liquid crystal display element (LCD) 6 for displaying information on the setting state and shooting of the camera,
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.
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 a switching mechanism (not shown) when driving each driving mechanism such as the photographing lens 9 and the shutter 19, or each driving mechanism is provided with another motor. Good.

In such a configuration, the CPU 1 controls the camera 1 based on the operating states of the switches 13a and 13b.
The shooting sequence of 0 is executed and controlled. That is, based on the output of the monolithic accelerometer 3, in addition to the warning display by the in-view LCD 6a for camera shake warning, the distance measuring section 5a for autofocus at the time of shooting, and the photometric circuit 5b for measuring the brightness of the subject for exposure control. To drive the motor 18 via the IFIC2 described above by receiving the necessary signal.
Drive control.

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 photo interrupter 17 according to the position of the presence or absence of the adjustment hole, and supplies the signal to the CPU 1. The CPU 1 receives the signal and monitors the rotation state of the motor 18. Further, the CPU 1 causes the strobe unit 8 to emit auxiliary light as needed. Further, the CPU 1 reads the focal length state of the taking lens from the focal length detection unit 101 in order to set the subject image data range used for camera shake detection.

FIG. 13 shows an example of a warning pattern displayed on the LCD 6a in the finder, where the code A is the screen A of the A pattern, the code B is the screen B of the B pattern, and the code C is the screen C of the C pattern. Is shown.

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 a light-shielding pattern displayed in the panoramic photography setting. First, as shown in screen A, only the upper area is shielded from light, and then 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 into the finder can be made aware of the occurrence of camera shake. The blackout display can be performed by simultaneously shielding the patterns A, B, and C from light.

With such a display, it is possible to express a feeling that the finder screen is swaying.
If the camera shakes again after re-holding the camera, the screen returns to the screen D shown in FIG. 14A or the screen E shown in FIG. 14B according to the normal or panorama mode, and the subject can be monitored.

FIG. 15 is a diagram showing a display example (pattern 1) of the camera shake warning displayed on the in-viewfinder LCD 6a.

As shown in FIG. 15, this pattern 1 is
Similar to the pattern described in FIG. 13, the light-shielding portion displayed when the panoramic shooting is set is used. In this pattern, the upper and lower light-shielding portions are alternately displayed as screen A and screen C. This pattern is different from the warning pattern in FIG. 13 in that the central portion of the screen is always visible, so that the facial expression of the subject does not become difficult to see in the panoramic shooting mode. In addition, since it blinks,
Unlike the normal display in (a) and FIG. 14 (b), there is no misunderstanding by the user, and the user can be surely notified using the warning display.

Next, the vibration detection principle of the camera having such a configuration will be described in detail with reference to FIGS. 6 to 11.

6A and 6B are explanatory views for explaining the vibration operation when the camera shake occurs. FIG. 6A shows a state when the user holds the camera, and FIG. 6B shows the vibration of the camera. It is a figure which shows a detection direction. FIG. 7 is a characteristic diagram showing time-acceleration characteristics according to the moving distance of the camera,
FIG. 7A shows a case where the movement amount of the camera is large, and FIG.
Indicates the case where the movement amount of the camera is small.
FIG. 8 is an explanatory diagram for explaining the vibration detection operation of the camera of the present embodiment, and FIGS.
The operating procedures and display examples are shown in FIG. Further, FIG. 9 is a configuration diagram showing a configuration of display segments in the LCD of the camera, FIGS. 10 and 11 are external views showing a warning display state of the camera, and FIG. FIG. 11 is a perspective view seen from the rear side of the camera in the operated state, and FIG. 11 is a perspective view seen from the front side of the camera with the self-timer LED blinking. Now, it is assumed that the user uses a camera to perform shooting. In this case, the user 100 may hold the camera 10 with one hand as shown in FIG. 6A. In such a case, the camera 10 tends to slightly vibrate in an oblique direction. That is, such a minute vibration of the camera 10 can be decomposed into movements in the X direction and the Y direction, as shown in FIG.

In general, a general user is unconscious about such a minute vibration or causing an action of “blurring” at the time of photographing, and in response to this, in the camera 10 of the present embodiment, the camera 10 is By detecting this minute vibration and performing the display as described in FIG. 13,
Since the user 100 takes a picture by taking measures to suppress vibration such as attaching the left hand 100a to the camera, it is possible to take a picture without failure due to camera shake.

However, since a high-class user who is annoyed by the constant warning and who is worried about camera shake may sometimes enjoy taking pictures using camera shake effectively, this implementation In this mode, the holding check function is set as one of the shooting modes, and the holding check function is improved so that it can be set only when the user thinks it is necessary. That is, the switch 1 as shown in FIG.
3c and the liquid crystal display unit 6 are provided, and only the functions of the film counter 6a and the like are activated in the normal state, and only when the user 100 operates the mode selector switch 13c with the left hand 100a or the like as shown in FIG. 8B. , The camera shake mode is set, and when this mode is set, FIG.
As shown in FIG. 8C, when the display segments 6b and 6c are displayed and the display segment 6b blinks, the user can recognize that the holding check mode has been entered.

Further, in this embodiment, 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 liquid crystal display unit (LCD) 6 is changed. There is no burden. In addition, as shown in FIG. 9, each of the display segments 6b,
Since the 6c are wired in the liquid crystal display section 6 so as to be independent of each other, the independent display control by the CPU 1 is possible.

Setting this mode and holding the camera 10,
If the holding check is unstable, the LCD 6a in the finder flickers as described above and the user 10
0 may be used as a warning, and as shown in FIG. 10, the LED 11 near the finder eyepiece 61 of the camera 10 may be blinked to give a warning.

In this case, when viewed from the front, the camera 10
The external appearance may be as shown in FIG. 11, and the self-timer display LED 65 may be made to blink so that when the owner of the camera 10 asks another person to take a picture, the holding of the photographer can be checked. .

Next, the difference between the output of the AF sensor (image signal) and the output of the acceleration sensor, which is a feature of the present invention, will be described in detail with reference to FIG.

Now, for example, by holding the camera 10 by the user 100, as shown in FIGS.
As shown in (b), it is assumed that the camera 10 itself causes camera shake having movements in both X and Y direction components.

In this case, in the camera 10 of this embodiment, the moment the camera 10 moves as shown in FIG.
Acceleration sensor (acceleration IC) 3 at the timing of t = t1
Outputs a signal when the camera 10 starts moving, but if the camera 10 is moving at a constant speed thereafter, the acceleration sensor 3 does not output a signal because the acceleration is not acceleration despite the camera shake. Again, when the camera stops, t = t7
At this timing, the acceleration sensor 3 outputs in such a direction as to stop the previous constant velocity motion.

As a supplement to this acceleration sensor, the image sensor (AF sensor) of the camera outputs an image signal that continues to change even during constant velocity motion. Therefore, if this output is judged, even if the output of the acceleration sensor 3 is zero. The CPU 1 of the camera 10 can determine that the camera 10 is moving.

Further, as shown in FIG. 7B, the acceleration sensor 3 may output an output even if the image signal hardly changes. This is the state in which the user 100 is trying to fix and hold the camera 10 while shaking, as shown in FIG.
Unlike the state shown in (1), the change in the image is small, and in fact, there are many cases in which it is possible to take a good picture depending on the focal length even if this is taken. That is, even if the acceleration sensor 3 outputs a large output, the camera 10 may only be slightly moving, and even if the acceleration sensor 3 reacts only occasionally,
The camera position may change greatly.

Further, there are some limits to the blur determination by the AF sensor. For example, in a scene where there is no contrast or a scene where the image is dark and the image cannot be seen, the determination cannot be made because the change in the image is not known. Further, as in the present embodiment, the sensor having only one detection direction cannot recognize the movement or image change of the camera 10 having a different force direction, and when the camera 10 shakes too much, the AF sensor The position monitored by will be displaced and the image will change completely, making it impossible to accurately determine the amount of blur.

Therefore, it is necessary to devise a method for properly determining the blur by properly using these two sensors. The camera according to the present embodiment has a holding check mode function in which a sensor based on such two detection methods is mounted. The display control and the like performed by the CPU 1 in the camera with the holding check mode function in the sequence according to the built-in program will be described in detail with reference to the flowchart shown in FIG.

For example, in the camera 10 shown in FIG. 11, when the barrier 10a for protecting the front lens is opened,
The user first carries out the framing, the holding operation has not been started yet, and the camera 10 is largely moved. Therefore, the determination by the AF sensor is not effective. Since the AF sensor monitors only a narrow part of the screen, a large camera movement cannot be evaluated quantitatively at all.

Therefore, the CPU 1 in the camera 10
By the determination process of step S1, first, the output of the acceleration sensor 3 is determined, and even if there is a shock when the barrier is opened or when the user holds the camera, a holding warning is given for a predetermined time by the process of step S2. Is prohibited, and then the focal length f of the taking lens is detected and the process proceeds to step S4 in order to set the image signal range used for camera shake detection in the subsequent step S3.

In the determination processing of step S4, the CPU
1 determines whether or not the focal length f detected in step S3 is shorter than a predetermined focal length fo. After that, the camera shake determination value for wide is set in the subsequent processing of step S6, and then the processing proceeds to step S8. On the other hand, if it is determined to be long, the CPU 1 sets the telephoto imaging signal use range in the process of step S7, and then sets the telephoto blurring determination value in the process of step S8. The process proceeds to step S9.

Note that the image pickup signal use range and the camera shake determination value here are not limited to two kinds of switching for wide and tele, and they can be continuously switched according to the focal length of the taking lens. It may be controlled to.

Next, the CPU 1 controls to perform image detection using the AF sensor in the processing of step S9. As a result, it is determined whether the image detection is suitable for the holding check.
When it is determined by the determination process of 10 that the detected image has low brightness, the determination process is performed, and the flow of the blur determination by acceleration detection that does not use the image signal (steps S15 to S19) is executed.

This is to issue a warning (step S18) when the acceleration sensor outputs a signal and it is not detected that the reverse acceleration is output for a predetermined time (step S16 to step S17). As shown in FIG. 7A, it is determined that the camera continues to move at a constant speed, and the user is informed that camera shake may occur.

In this state, since the user may intend to follow the shot, the LCD in the finder does not blink, for example (FIG. 13 etc.), and the LED 11 near the finder eyepiece as shown in FIG. Alternatively, the warning may be different from the case where the AF sensor is also used (step S26).

On the other hand, if it is judged in the judgment processing of step S10 that the detected image does not have low brightness, C
The PU 1 determines whether or not it is a low-con in the processing of the subsequent step S11, moves the processing to step S20 if it judges that it is not the low-con, and continues the processing if it judges that it is the low-con. Move to.
In the process of step S12, the CPU 1 again compares the focal length f of the taking lens with the predetermined focal length fo, and when it is determined that the focal length f of the taking lens is longer, the CPU 1 proceeds to the process of the following step S13. Then, the use range of the image pickup signal is expanded, and then it is determined again in the determination process of step S14 whether or not it is a low contrast. As in the case of time, control is performed so as to execute the blur determination flow by acceleration detection (steps S15 to S19).

With the above processing, the use range 113 of the image signal used for the camera shake detection is the image signal detection range within the shooting screen 111 as shown in FIG. 16A when the focal length of the taking lens is on the short focus side. The range is set to be approximately the same as 112, and the image signal detection range 11 is set on the long focus side as shown in FIG.
It is set to the range within the photographing screen 111 in 2. In addition, when the image signal in the use range 113 of the image signal in which the focal length of the taking lens is set on the long focus side is low contrast, FIG.
As shown in (c), the use range 113 of the image signal is expanded to a range substantially the same as the image signal detection range 112.

As a result, camera shake detection is normally performed on the basis of the subject information in the photographing screen 111, and the photographing screen 111 is detected.
Shooting screen 111 only when there is no subject information in
Since the outside subject information is used, erroneous detection due to the influence of the subject outside the photographing screen 111 can be prevented, and accurate camera shake detection can be performed.

When the image signal is suitable for the camera shake determination, the CPU 1 repeats the image detection at a predetermined time interval (step S22) in the flow from step S20 onward (steps S21 and S24), and the image detection signal is detected. Difference X
(N) -X (n-1) is obtained, and the difference X (n) -X (n- between the image detection signals is obtained by the determination processing in step S25.
It is determined whether 1) is larger than the camera shake determination value Xc.
In this case, when it is determined that the value is larger than the camera shake determination value Xc, the CPU 1 shifts the processing to step S26 and controls the display so as to give a warning that the holding is insufficient in the processing. .

With these warnings, the user recognizes that he / she is unconsciously shaking, and can take measures to prevent camera shake by holding with both hands or placing it on something. .

Further, the CPU 1 determines the difference X (n) -X (n-1) of the image detection signals in the determination processing of the subsequent step S27.
Is larger than the predetermined level Xcc larger than Xc, and if it is larger than Xcc, it is assumed that the user has taken a completely different angle or changed the composition. Therefore, the processing is returned to step S1. If it is determined that the value is smaller than Xcc in the determination processing in step S27, CP
U1 returns the process to step S22.

On the other hand, if it is determined in the determination processing in step S25 that the difference X (n) -X (n-1) between the image detection signals is smaller than the predetermined level Xc, the image signal becomes stable. Since the release is possible, the CPU 1 determines that the release has been pressed in the determination process of step S28, and if it is determined that the release has been pressed, the CPU 1 executes the exposure sequence from step S30 onward, If it is determined that it has not been performed, the process proceeds to step S
Return to 22.

When the release is pressed, the CPU 1
First, in the processing of step S30 and step S31,
Focusing and distance measurement for that purpose are performed, and in the subsequent step S32, the exposure time is determined based on the brightness information obtained by the image detection in step S9, and at the same time, the exposure is started.

During this time, the camera shakes if the camera shakes, so the CPU 1 detects the acceleration in the process of step S33, and obtains the acceleration g due to a shock or the like when the release button is pressed. That is, if this g is large, the camera shake photograph is obtained even if the exposure time is short, and if the g is small, the camera shake photograph is obtained even if this is small. In order to determine this, the CPU 1 counts the exposure time in the determination process of the subsequent step S34, and when determining that the exposure has ended in step S35, determines the g and the exposure obtained in the process of the subsequent step S36. Calculate speed from time tEND,
Since the amount of movement can be calculated from the fact that the speed has changed only for the time of tEND, if this exceeds the allowable amount ΔY of the lens, display control is performed so as to issue a warning in the process of step S37. If the amount of movement does not exceed the allowable range ΔY, the process ends.

As described above, only the change in the velocity can be known only by the acceleration, but in the present embodiment, first, it is determined that the output (image signal) of the AF sensor does not change because it is stopped at the predetermined position. Therefore, it is possible to accurately determine how much the camera has moved during exposure with reference to this.

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

Further, since the camera shake determination value is switched according to the focal length of the photographing lens, it is possible to prevent the camera shake warning from becoming excessive while accurately detecting the camera shake.

Further, in combination with the signal of the acceleration sensor, X
Not only is it possible to detect a shake in the direction Y and the direction Y to cope with a dark scene or a low-contrast scene, but by using it as a stillness detection sensor, it is possible to accurately calculate the amount of camera movement from the output of the acceleration sensor. .

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

Needless to say, if the position of the taking lens is corrected based on the calculated amount of movement, it can be applied to a camera with anti-vibration function.

The present invention is not limited to the above-mentioned embodiment, and the combination and application of each constituent element are also applied to the present invention.

[0086]

As described above, according to the present invention,
Especially in shooting scenes where camera shake is a concern, if you set the holding check mode, a warning will be issued when the camera shakes and the photographer will be made aware of the camera shake, so it is possible to take pictures without failure due to camera shake. Become. Moreover, at the time of holding determination, the sensor used as a conventional sensor for distance measurement is also effectively used for camera shake determination, so that highly reliable camera shake determination can be performed without increasing the cost.

Further, it is possible to provide a camera with a hand-shake function which is convenient for the user without giving unnecessary warnings.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration example of a camera with a camera shake detection function according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing an electrical block configuration of the camera of the present embodiment.

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

FIG. 4 is a configuration diagram showing a specific configuration of an acceleration IC.

FIG. 5 is a block diagram showing a configuration example of a processing circuit in the acceleration IC.

FIG. 6 is an explanatory diagram illustrating a vibration operation when camera shake occurs.

FIG. 7 is a characteristic diagram showing a time-acceleration characteristic according to a moving distance of a camera.

FIG. 8 is an explanatory diagram for explaining a vibration detection operation of the camera of the present embodiment.

FIG. 9 is a configuration diagram showing a configuration of a display segment in the LCD of the camera.

FIG. 10 is a perspective view seen from the rear side of the camera in a state where the warning display section blinks.

FIG. 11 is a perspective view of the camera with the self-timer LED blinking as seen from the front side.

FIG. 12 is a flowchart showing an example of a characteristic display control operation by the CPU of the camera.

FIG. 13 is a diagram showing an example of a warning pattern displayed on the LCD in the viewfinder.

FIG. 14: LCD in viewfinder when no camera shake occurs
FIG.

FIG. 15 is a diagram showing one display example of a camera shake warning displayed on the LCD in the viewfinder.

FIG. 16 is an explanatory diagram for explaining a use range of subject image data used for camera shake detection, which is switched according to focal length information of a photographing lens.

[Explanation of symbols]

1 ... CPU, 2 ... IFIC, 3 ... Acceleration IC (monolithic accelerometer, acceleration sensor), 4 ... Memory, 5 ... AF sensor, 5a ... AF section, 5b ... Photometric section, 5c ... Sensor array, 5d ... Light receiving lens , 6 ... Liquid crystal display (LCD), 6a ... LCD in viewfinder, 7 ... Flexible substrate, 8 ... Strobe circuit, 9 ... Shooting lens, 10 ... Camera with camera shake detection function, 10A ... Camera body, 11 ... Warning display section , 12 ... Connector, 13 ... Switch pattern, 13a, 13b ... Switch, 14 ... Hard printed circuit board, 16 ... Rotating blade, 17 ... Photointerleaver, 18 ... Motor, 19 ... Shutter, 20 ... Silicon substrate, 21 ... Oxidation Membrane, 22 ... Polysilicon layer (movable electrode), 23a, 23b ... Arm part, 24, 25 ... Other electrode, 29 ... Processing circuit, 61 ... viewfinder eyepiece section, 65 ... self-timer display LED, 101 ... focal length detection section.

Claims (4)

[Claims] 1. A camera with a camera shake detection function for detecting camera shake using an AF sensor of a camera for detecting a vibration state of a camera body, wherein object image data output from the AF sensor at predetermined time intervals. When performing camera shake detection based on the image shift amount of the subject image data, the use range of the subject image data used for camera shake detection and the camera shake determination value are switched according to the focal length of the photographing lens. A camera with a camera shake detection function. 2. The camera shake determination value is set so as to be gentle when the focal length of the photographing lens is on the short focal side and to be a severe value when the focal length is on the long focal side. A camera with a camera shake detection function according to claim 1. 3. When the focal length of the photographing lens is equal to or greater than a predetermined focal length and the contrast within the normal use range of the subject image data used for camera shake detection is low, the use range of the subject image data is widened. The camera with a camera shake detection function according to claim 1, wherein camera shake detection is performed. 4. When the camera shake is detected, the display means provided in the camera displays the occurrence of the camera shake to alert the user.
The camera with a camera shake detection function described in any one of 1.