JPH05142616A - Blurring preventing camera - Google Patents

Abstract

PURPOSE:To accurately grasp the circumstances of camera shake just before actuation and to reduce failure by outputting a signal in accordance with the magnitude of pressure applied to a shutter button in the case of pushing in the shutter button. CONSTITUTION:When a 1st switch SW1 is turned on by pushing in the shutter button 11, a camera is in a photographing preparing state, and when a 2nd switch SW2 is turned on by pushing in the button 11 further and a fixed time elapses, a photographing lens is stopped down and the opening/closing of the shutter is performed. A system control means 1 measures the time from turning on the 1st switch SW1 till turning on the 2nd switch SW2 and predicts the occurrence of blurring in the case that the measuring time is shorter than the fixed time. Thus, the camera shake is prevented by detecting the speed of pushing the button 11, making the shutter speed higher within the ability of the camera in accordance with the detected speed, and releasing at a diaphragm value for increasing brightness within the ability of a mounted lens.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-shake camera that predicts camera shake in advance and performs appropriate anti-shake processing based on the result of the prediction.

[0002]

2. Description of the Related Art As a camera having a blur prevention function,
A camera using an acceleration sensor has been conventionally known.
For example, in Japanese Patent Laid-Open No. 63-53524, the acceleration applied to the camera is detected by an acceleration sensor, and the detection result is integrated twice to obtain the camera shake amount immediately before shooting, and this shake amount and a preset aperture. A technology to prevent camera shake by determining whether or not a photograph is blurred from the combination of the value and the shutter speed, and if it is determined to be blurred, open the diaphragm and shift the shutter speed to a higher speed. Is disclosed.

[0003]

However, in the above-mentioned conventional example, since it takes a calculation time to integrate the output of the acceleration sensor twice, there is a disadvantage that it is difficult to grasp the blurring state immediately before the operation. In addition, an acceleration sensor for detecting a small acceleration such as a camera shake has a high cost due to its complicated structure, and its constituent members are vulnerable to an impact, so that it is easy to break down when incorporated in the camera. There is. SUMMARY OF THE INVENTION It is an object of the present invention to provide a camera shake prevention camera that accurately grasps a camera shake situation immediately before operation and has few failures.

[0004]

A camera for preventing blurring according to the present invention comprises a pressure measuring means (1, 2d, 1d, 2d, 3d) for outputting a signal according to the magnitude of pressure applied to a shutter button (11) when the shutter button (11) is pushed. 30) and a blur prediction unit (1) for predicting camera shake based on the signal output from the pressure measuring unit.

In this case, the pressure measuring means includes the first and second switches (SW1 and SW2) which are sequentially turned on by pressing the shutter button (11) and the second switch after the first switch is turned on. And a time measuring means (1) for measuring a time interval until turning on.

Further, in this case, the pressure measuring means is a strain measuring sensor (2d, 30) which is distorted by pressing the shutter button (11) and outputs a signal corresponding to the distorted amount. Further, in this case, the pressure measuring means has the first and second switches (SW1 and SW2) which are sequentially turned on by pressing the shutter button (11).
And a fixed time measuring means (1) for measuring the elapse of a fixed time after the second switch is turned on, and a contact piece (2c) on the high rigidity side of the second switch, which is distorted within a fixed time. It is characterized by being a strain measurement sensor (2d) for measuring the maximum strain amount.

The anti-shake camera according to the present invention is
When the blur prediction means (1) predicts a camera shake, at least one of the shutter speed and the aperture value is changed in a multi-step or stepless manner according to the magnitude of the pressure applied to the shutter button to prevent the camera shake. It is characterized by adding prevention means (1). Further, the anti-shake camera according to the present invention is characterized by adding release prohibiting means (1) for prohibiting release when the shake predicting means (1) predicts camera shake.

[0008]

According to the present invention, the camera shake is caused by the vibration of the camera, and the vibration of the camera is abruptly excited when the photographer pushes the shutter button. Further, the faster the shutter button is pushed, the stronger the force is to push it. This was done by paying attention to the fact that the more you press, the greater the vibration of the camera.

In the first embodiment, first, the time measuring means measures the time interval at which the first and second switches are turned on to detect the pressing speed of the shutter button. Since the stroke between the first and second switches is always constant, the pressing speed of the shutter button can be detected by measuring the time interval between them. Then, the blurring predicting means predicts the blurring based on the pushing speed thus detected, and the combination of the shutter speed and the aperture value programmed based on the prediction result is changed as necessary to prevent the camera blurring.

Further, in the second and third embodiments, the distortion measuring sensor detects the pushing force of the shutter button, the blur predicting means predicts the camera shake corresponding to the pushing force, and based on the prediction result, Camera shake is prevented by changing the programmed combination of aperture value and shutter speed as necessary.

As described above, according to the present invention, the camera shake is predicted by detecting the pressing speed or the pressing force of the shutter button. Therefore, the number of failures is less than that in the case of using the conventional acceleration sensor, and moreover, The state of camera shake immediately before the operation can be accurately grasped and an appropriate shake prevention processing can be performed.

[0012]

1 is a block diagram showing a first embodiment of an anti-shake camera according to the present invention. In this example,
The system control unit 1 having a microcomputer configuration is configured to perform various controls of the camera.

The system control unit 1 includes a switch detection unit 3 for detecting the on / off state of the shutter switch 2, a photometric unit 4 for detecting the brightness of the subject, and the sensitivity and latitude of the film loaded in the camera. Alternatively, a film sensitivity setting unit 5 to be set, an LCD driver 7 for displaying and driving a liquid crystal display (LCD) 6 provided outside the camera or in the viewfinder, a shutter drive unit 8 based on a command from the system control unit 1, and An exposure control unit 10 that controls the diaphragm drive unit 9 is connected to each.

The shutter switch 2 is a shutter button 11
A first contact piece 2a that is bent by pushing the first contact piece 2a, a second contact piece 2b that is bent by pushing down the first contact piece 2a, and a third contact piece 2c that is bent by pushing down the second contact piece 2b. 1st and 2nd contact piece 2a and 2b make 1st switch SW1 2nd and 3rd contact piece 2
The second switch SW2 is configured by b and 2c.

When the first switch SW1 is turned on by pressing the shutter button 11, the camera is ready for shooting, and when the second switch SW2 is turned on by further pressing the shutter button 11 and a certain time has elapsed, the shooting lens Is narrowed down and the shutter is opened and closed. As shown in FIG. 2, the shutter switch 2 is attached to the upper left part of the front of the camera body 20, and the first to third contact pieces 2a to 2c are respectively formed in the mold 2.
The shutter button component is formed by inserting the shutter button component into the shutter button component.

Next, the shake prevention operation by this structure will be described with reference to the flow chart shown in FIG. First, when the shutter button 11 is pressed, the first contact piece 2a bends and contacts the second contact piece 2b, so that the first switch SW
When 1 is turned on (step S1), the switch detection unit 3 sends to the system control unit 1 a signal indicating that the first switch SW1 is turned on. The system control unit 1 receives this signal and starts measuring the time until the second switch SW2 is turned on (step S2). This measurement is performed by counting pulses of a predetermined cycle with a counter in the system controller 1.

When the second switch SW2 is turned on (step S3), the switch detection unit 3 causes the second switch SW2 to operate.
A signal indicating that is turned on is sent to the system control unit 1. Upon receiving this signal, the system control unit 1 stops counting the pulses in the internal counter, and the count value T at that time is the time from when the first switch SW1 is turned on to when the second switch SW2 is turned on. T (step S
4).

Next, the system controller 1 determines whether or not this measurement time T is longer than a certain time T ₁ (step S5). If time T is longer than time T ₁ ,
It is determined that the shutter button 11 is pressed slowly, and it is determined that the camera shake does not occur, and the combination of the shutter speed T _V and the aperture value A _V is determined according to the program diagram shown in FIG. 4 (step S6), and the release is performed with this combination ( Step S7).

When the measurement time T is shorter than the fixed time T ₁ , the occurrence of blurring is predicted. Therefore, the system control unit 1
Determines whether the measurement time T is shorter than the fixed time T _{1 and} longer than the fixed time T ₂ (T ₂ <T ₁ ) (step S8). If this condition is satisfied, it is determined that a slight shock is applied to the camera when the shutter button 11 is pressed, and it is predicted that slight blurring will occur, so that the program diagram shown in FIG. 4 is deviated. Shutter speed to "T _V +1" and the aperture value to "A"
" _V- 1" is determined (step S9), and the determined combination is released (step S7).

For example, as shown in FIG. 4, when the subject brightness is E _V 8, the shutter speed is 1 / th in the program diagram.
The aperture value becomes F2.8 (A _V 3) for 30 seconds (T _V 5), but in step S9, the shutter speed is 1/6 faster.
0 seconds (T _V 6) and the aperture value is one step brighter F2 (A
Release as _V 2).

By the way, in this case, when the determined shutter speed "T _V +1" becomes faster than the maximum shutter speed T _VF of the camera, or when the aperture value "A _V -1" is smaller than the open value A _{VO of the} mounted lens. May occur (step S1)
0). In such a case, set the shutter speed to the maximum speed T
Fix the exposure to _VF and adjust the exposure with an aperture within the latitude range of the film, or open the aperture value A of the lens.
Only the shutter speed is shifted to the high speed side within the latitude allowable range while keeping _VO (step S11), and the combination is released (step S7).

When it is determined that the measurement time T is shorter than the constant time T ₂ (step S8), the measurement time T is the constant time T 2.
_{It is} determined whether it is shorter than _{2 and} longer than a fixed time T ₃ (T ₃ <T ₂ ) (step S12). If this condition is satisfied, it is determined that a strong shock has been applied to the camera when the shutter button 11 is pressed, and it is predicted that blurring will occur, and the shutter speed deviates from the program diagram shown in FIG. Is set to “T _V +2” which is two steps faster and “A _V −2” which is set to two steps for the aperture value (step S13), and the combination is released (step S).
7).

Also in this case, the shutter speed "T _V
+2 ”is faster than the highest shutter speed T _VF of the camera, or the aperture value“ A _V −2 ”is the open value A _{VO of the} mounted lens.
Since it may become smaller (step S14),
As above, fix the shutter speed to the maximum speed T _VF and adjust the exposure with the aperture within the latitude range, or leave the aperture value of the lens at the open value A _VO and only the shutter speed within the latitude range. It shifts to the high speed side (step S11), and the combination is released (step S7).

If the measurement time T is shorter than the fixed time T ₃ (step S12), it is judged that the camera is given a very strong shock because the shutter button 11 is suddenly pressed, and it is predicted that a large blur will occur. 1
The release prohibition mode is set so that the shutter does not release even if 1 is pressed (step 15), the release prohibition display is made on the LCD 5 (step 16), and the process ends.

As described above, in this embodiment, attention is paid to the fact that the faster the shutter button is pressed, the more the camera shake is generated, and the speed at which the shutter button is pressed is detected, and within the range of the camera capability according to this speed. In order to prevent camera shake by increasing the shutter speed and releasing with a bright aperture value within the range of the ability of the mounted lens. The number of steps for ranking the measurement time T is preferably about 3 steps (“a little blur”, “blur”, “large blur”) as in the present embodiment, but it is not limited to this and is arbitrary. The number of stages may be set.

Next, a second embodiment of the present invention will be described. In this embodiment, the stronger the pressing force of the shutter button is, the stronger the force is applied to the camera, and the larger the movement of the camera during exposure is, which is likely to cause camera shake, and the pressing force of the shutter button is measured. By doing so, the camera shake is predicted.

FIG. 5 is a block diagram showing a second embodiment of the present invention. This embodiment is similar to the first embodiment shown in FIG. 1 except that a strain measuring sensor 2d such as a strain gauge is mounted on the surface of the third contact piece 2c. It has the same configuration as the example.

In this structure, when the shutter button 11 is pushed in, the first contact piece 2a and the second contact piece 2b come into contact with each other to turn on the first switch SW1 and the second contact piece 2b and the second contact piece 2b. The second switch SW2 is turned on by the contact with the contact piece 2c of No. 3. Since the third contact piece 2c has higher rigidity than the other contact pieces 2a and 2b, it is possible to know from the feel of a finger that the second contact piece 2b comes into contact and the second switch SW2 is turned on. There is. On the contrary, since the first and second contact pieces 2a and 2b have lower rigidity than the third contact piece 2c, the pushing force of the shutter button 11 is not so affected.

The force pushing the third contact piece 2c can be measured by the strain measuring sensor 2d fixed to the surface of the contact piece 2c. Since the strain of the contact piece 2c is proportional to the force acting on it and the deflection, the force acting on the contact piece 2c can be measured by measuring the strain of the contact piece 2c. That is, the stronger the shutter button 11 is pressed within a certain period of time, the greater the deflection of the contact piece 2c, and the greater the strain of the strain measurement sensor 2d. The strength of the force pressing the shutter button 11 can be known from this distortion, and the maximum distortion of the distortion measuring sensor 2d becomes the maximum pressing force that acts on the camera.

Next, referring to the flow chart shown in FIG. 6, the blur prevention operation according to the second embodiment of the present invention will be described. First, when the first contact piece 2a is bent by pressing the shutter button 11 and the first switch SW1 is turned on (step S21), the switch detection unit 3 makes the first contact.
A signal indicating that the switch SW1 has been turned on is sent to the system control unit 1, and the camera is instructed to start shooting preparation.

Next, when the second switch SW2 is turned on (step S22), the switch detection unit 3 sends a signal indicating that the second switch SW2 is turned on to the system control unit 1. When the pushing force of the shutter button 11 is strong, the pushing is continued after the second switch SW2 is turned on. Therefore, the system control unit 1 waits for a certain period of time after the second switch SW2 is turned on. ,
The strain of the contact piece 2c is measured by the strain measuring sensor 2d (steps S23 and S24), and the maximum pushing force F applied to the camera is calculated from the maximum strain amount therein (step S).
25).

Next, the system controller 1 determines whether the pushing force F is weaker than a certain force F ₁ (step S26). If the pushing force F is weaker than a constant force F _1, it is determined that the shutter button 11 is pushed with almost no force applied to the camera, and it is assumed that blurring does not occur, and the shutter speed is set according to the program diagram shown in FIG. The combination of T _V and aperture value A _V is determined (step S2
7) Release with this combination (step S2)
8).

When the pushing force F is stronger than the constant force F ₁ , the occurrence of blurring is predicted. Therefore, the pushing force F is stronger than the constant force F ₁ , and the constant force F ₂ (F ₁ <
It is determined whether or not it is weaker than F ₂ ) (step S29).
If this condition is met, shutter button 1
It is judged that a slight force is applied to the camera when 1 is pushed in, and it is predicted that a slight blur will occur, and it deviates from the program diagram shown in FIG. 4 and the shutter speed is increased to “T _V +1”, "A _V -1" with a further increase in aperture value
Respectively (step S30), and release with this combination (step S28).

In this case, the determined shutter speed "T _V +
1 ”is faster than the maximum shutter speed T _VF of the camera or the aperture value“ A _V −1 ”is smaller than the open value A _{VO of the} mounted lens (step S31), the shutter speed is set to the maximum speed T. Fix exposure at _VF and adjust the exposure with an aperture within the latitude range of the film, or leave the aperture value of the lens at the open value A _VO and shift only the shutter speed to the high speed side within the latitude range (step S3).
2), release with that combination (step S2)
8).

[0035] If a pushing force F is determined to stronger than constant force F ₂ than (step S29), strongly pushing force F is below a certain force F _2, and constant force F ₃ (F ₂ <F ₃₎ It is determined whether or not it is weak (step S33). If this condition is satisfied, it is determined that a strong force is applied to the camera when the shutter button 11 is pressed, and it is predicted that blurring will occur, and the shutter speed deviates from the program diagram shown in FIG. Is determined to be "T _V +2" which is two steps faster and "A _V -2" which is the aperture value opened by two steps (step S34), and the combination is released (step S28).

Also in this case, the shutter speed "T _V +2" becomes faster than the highest shutter speed T _VF of the camera,
Since the aperture value "A _V -2" may become smaller than the open value A _{VO of the} mounted lens (step S35), the shutter speed is fixed to the maximum speed T _VF and the film latitude is changed as in the case described above. Adjust the exposure with an aperture within the allowable range, or leave the aperture value of the lens at the open value A _VO and shift only the shutter speed to the high speed side within the allowable range of latitude (step S32), and release with that combination (step S32). S28).

When the pushing force F is stronger than the constant force F ₃ (step S33), it is determined that the shutter button 11 has been pushed deeply with a very strong force, and the shutter button 11 is pushed in anticipation of a large blurring. Is set to the release prohibition mode in which no release is performed (step S36), LC
The release prohibition display (step S37) is performed at D5, and the process ends.

As described above, in this embodiment, attention is paid to the fact that the camera shake is more likely to occur as the shutter button is pushed with a stronger force, and the pushing force of the shutter button is detected from the distortion amount acting on the contact piece of the shutter switch. However, the camera shake is prevented by increasing the shutter speed within the range of the ability of the camera according to the pushing force and releasing with a bright aperture value within the range of the ability of the mounted lens. Incidentally, the number of steps for ranking the strength of the pushing force is preferably about three steps as in this embodiment, but it is not limited to this, and any number of steps may be set.

Next, a third embodiment of the present invention will be described. In this embodiment, similarly to the second embodiment described above, the camera shake is predicted by focusing on the relationship between the pushing force of the shutter button and the camera shake and measuring the pushing force of the shutter button. ..

FIG. 7 is a block diagram showing a third embodiment of the present invention. This embodiment is different from the second embodiment shown in FIG. 5 in that a semiconductor pressure sensor 30 is provided in place of the shutter switch 2 and a sensor detection unit 31 is provided in place of the switch detection unit 3. However, it has the same structure as the second embodiment.

FIG. 8 is a block diagram showing an example of the semiconductor pressure sensor 30, which is a substrate 3 having a concave portion kept in vacuum.
0a is provided with a metal thin piece 30b having a high melting point and easily thinned, an insulating film 30c is attached on the surface of the metal thin piece 30b, a semiconductor material 30d is grown on the insulating film 30c, and an insulating layer 30e is formed around the semiconductor material 30d. Then, the electrodes 30f are connected to both ends of the semiconductor material 30d.

In this structure, when pressure is applied to the semiconductor material 30d by the shutter button 11, the resistance of the semiconductor material 30d changes according to the magnitude of the strain, so that the resistance value between the electrodes 30f changes accordingly. .. Therefore, by detecting the output signal between the electrodes 30f,
As shown in FIG. 9, the pushing force of the shutter button 11 can be detected.

In this case, when the sensor output has a constant output value P1, it indicates that the shutter button 11 is half pressed, and when the sensor output has a constant output value P2 larger than the output value P1, the shutter is released. This indicates that the button 11 is fully pressed. In addition, the sensor output is the output value P2 to P
When 3 (P2 <P3), it is assumed that the camera shake does not occur, and the combination of the shutter speed Tv and the aperture value Av is determined according to the program diagram shown in FIG.

Further, the sensor output is output values P3 to P4 (P
When 3 <P4), a slight strong force is applied to the camera, and it is predicted that slight blurring will occur, and the shutter speed is further increased to “T _V +1” and the aperture value is further increased to “A _V -1”.
To each. Also, the sensor output is the output value P4.
When the ~P5 (P4 <P5), joined by a strong force to the camera, in two steps faster the shutter speed foresaw the blurring occurs "T _V +2", the aperture was opened two-stage "A _V -2 "
To each.

Further, when the sensor output is equal to or higher than the output value P5, the shutter button 11 is pushed deeply with a very strong force, it is judged that a very strong force is applied to the camera, and it is predicted that a large blur will occur. The release prohibition mode is set so that the release does not occur even if the button 11 is pressed. In addition,
These series of operations are the same as the operations (steps S26 to S37) in the second embodiment described above.

Thus, in this embodiment, the above-mentioned second
In the same manner as the embodiment of the above, focusing on the relationship between the pushing force of the shutter button and the camera shake, the pushing force of the shutter button is detected from the output of the semiconductor pressure sensor, and the shutter is released within the range of the ability of the camera according to the pushing force. The camera shake is prevented by increasing the speed and releasing with a bright aperture value within the range of the ability of the mounted lens.

[0047]

According to the present invention, since the camera shake is predicted by detecting the magnitude of the pressure applied to the shutter button, the situation of the camera shake immediately before the operation can be accurately grasped, and the structure is also improved. It is possible to provide an anti-shake camera that is simple, has few failures, and is inexpensive.

According to the second aspect of the invention, since it is only necessary to measure the ON interval time of the first switch and the second switch, the electric power required for the acceleration sensor driving means is not required as in the conventional case, and the battery is not required. This has the effect of reducing the consumption of water.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing how a shutter switch is attached to a camera body.

FIG. 3 is a flowchart for explaining the operation of the first embodiment.

FIG. 4 is a program diagram showing the relationship between shutter speed and aperture value.

FIG. 5 is a block diagram showing a second embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of the second embodiment.

FIG. 7 is a block diagram showing a third embodiment of the present invention.

FIG. 8 is a configuration diagram of a semiconductor pressure sensor.

FIG. 9 is a diagram showing a relationship between pressure applied to a semiconductor pressure sensor and sensor output.

[Explanation of symbols]

 1 system control unit 2 shutter switch 2c contact piece 2d strain measurement sensor 3 switch detection unit 11 shutter button 30 semiconductor pressure sensor 31 sensor detection unit SW1 first switch SW2 second switch

Claims (6)

[Claims] 1. A pressure measuring unit that outputs a signal according to the magnitude of the pressure applied to the shutter button when the shutter button is pressed, and a blur that predicts camera shake based on the signal output from the pressure measuring unit. An anti-shake camera, which includes: a predicting means. 2. The first pressure measuring means is sequentially turned on by pressing the shutter button.
And a second switch, and a time measuring unit that measures a time interval from when the first switch is turned on to when the second switch is turned on. camera. 3. The anti-shake camera according to claim 1, wherein the pressure measuring unit is a distortion measuring sensor that distorts when the shutter button is pressed and outputs a signal according to the distortion amount. 4. The first pressure measuring means is sequentially turned on by pressing the shutter button.
And a second switch, a constant time measuring means for measuring the lapse of a constant time after the second switch is turned on, and a fixed member on the high-rigidity side contact piece of the second switch, within the fixed time. The anti-shake camera according to claim 1, wherein the anti-shake camera is a distortion measuring sensor that measures a maximum amount of distortion. 5. When the blur prediction means predicts a camera shake, at least one of a shutter speed and an aperture value is changed in a multistep or stepless manner in accordance with the magnitude of the pressure applied to the shutter button, thereby changing the camera shake. An anti-shake camera according to claim 1, further comprising an anti-shake means for preventing the blurring. 6. The anti-shake camera according to claim 1, further comprising release prohibiting means for prohibiting release when the blur predicting means predicts camera shake.