JPH0122297Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a camera shutter device using a solid-state image sensor, more specifically, a camera shutter device that focuses an image of a subject on a solid-state image sensor, converts it into an electrical signal, and records it. This invention relates to a shutter device in a still camera.

Instead of still cameras that use conventional silver halide film, charge-coupled devices (CHharge Coupled Devices)
It is a well-known fact that still cameras using solid-state image sensing devices such as CCD (Device, CCD) have been prototyped and are about to be put into practical use. Still cameras using such solid-state image sensors record images optically using a photochemical reaction in which metallic silver is deposited upon exposure, whereas still cameras using silver halide film record images optically. The image is converted into an electrical signal by photoelectric conversion of subject light in a photoelectric conversion section corresponding to each picture element of the solid-state image sensor, and this is magnetically recorded.

By the way, the so-called recording of continuous images
In VTR (Video Tape Recorder) cameras,
Imaging devices using solid-state imaging elements have already been put into practical use. A VTR camera using this type of solid-state image sensor sequentially scans the photoelectric conversion unit corresponding to each pixel of the solid-state image sensor every 1/30 seconds.
It is designed to obtain an image signal for one frame, and this one frame image is equivalent to an image exposed at 1/30 second using a shutter device. Also, VTR cameras are 1/30
Since scanning of the photoelectric conversion section is continuously repeated every second, a shutter device is generally not provided, and therefore, the amount of exposure to the photoelectric conversion section is controlled exclusively by an aperture device. It's becoming like that.

The major difference between photography using a VTR camera and photography using a still camera is that a VTR camera records images continuously at regular intervals, whereas a still camera records still images. Therefore, in a VTR camera, a slight amount of blurring in each frame is acceptable, but in a still camera, image blurring is not allowed except for photographs intended for special effects. For this reason, in still cameras, a shutter device that controls the exposure time to the exposure screen has become indispensable.
A shutter device will always be installed inside the camera.

However, even though a shutter device is provided, in a still camera using a solid-state image sensor, it is not always necessary to use the shutter device for all shooting. This is because, as in the case of a VTR camera, if the photoelectric conversion unit corresponding to each pixel of a solid-state image sensor is scanned at a predetermined time, the image will be equivalent to that exposed by a shutter device operating at that predetermined time. can be obtained without using a shutter device.
In particular, I leave the shutter device open,
Similar to a VTR camera, the photoelectric conversion section of the solid-state image sensor is continuously scanned, and the resulting image signal allows the image to be monitored on a viewfinder made of a cathode ray tube, liquid crystal display, etc. In a still camera, for normal shooting, the solid-state image sensor is already continuously scanned at predetermined intervals without using a shutter device. One frame of the image signal may be recorded in synchronization with the pressing of the shutter release button. Then, if the subject is too dark or too bright, or if the subject moves rapidly, the shutter device may be activated as necessary.

In view of the above points, an object of the present invention is to configure a focal plane shutter with a leading shutter blade and a trailing shutter blade, and to provide a shutter opening holding means for holding the focal plane shutter in an open position. A solid-state imaging device that is equipped with a shutter and can normally record an image without using a shutter, but when exposure using a shutter is required, can record an image after exposure using a shutter. The object of the present invention is to provide a camera shutter device using the element.

According to the present invention, the focal plane shutter is composed of two blades, the shutter leading blade and the shutter trailing blade, so the mechanism is extremely simple and the high speed shutter speed and low speed shutter speed can be reduced. can be easily produced.

Additionally, since there is no need to wind the film and it is easy to move the focal plane shutter to the charge position, continuous shooting in shutter second exposure mode using the shutter can be done with a simple mechanism. It becomes like this.

Hereinafter, the present invention will be explained based on an illustrated embodiment.

FIG. 1 shows a camera shutter device using a solid-state image sensor according to the present invention. This shutter device includes a thin plate-shaped leading blade member 2 which is swingably supported on a support shaft 1 and has a shutter leading blade 2a formed at one end thereof, and a thin plate-shaped leading blade member 2 that is swingably supported on a support shaft 1. A trailing blade member 3 in the form of a thin plate, which is rotatably supported coaxially with the blade member 2 and has a shutter trailing blade 3a formed at one end, and the other arm of the leading blade member 2. An electromagnetic release electromagnet 5 that attracts the attraction piece 4 attached to the end, and an attraction piece 6 attached near the other arm end of the trailing blade member 3.
An electromagnet 7 for an electric shutter that attracts the shutter, and one end of which is attached to one arm of the leading blade member 2, giving the leading blade member 2 the ability to rotate clockwise around the support shaft 1. , a shutter opening spring 8 made of a compressible coil spring, and one end of which is attached to one arm of the trailing blade member 3, and rotates clockwise around the support shaft 1 on the trailing blade member 3. Shutter closing spring 9, which is a tight coil spring that gives a habit
and a movable pin 11 that engages with the partially arcuate cam surface 3b formed on the lower surface of the middle of the other arm of the trailing blade member 3, and this movable pin 11 is fixedly planted at the free end. Rotating arm 12 and this rotating arm 12
The main part of the shutter charge motor 13 is a shutter charge motor 13 whose base is fixed to an output shaft 13a.

The leading blade 2a of the leading blade member 2 and the trailing blade 3a of the trailing blade member 3 are connected to the photographing lens 1.
The solid-state image sensor 15 extends to the front position of the solid-state image sensor 15 arranged near the focal plane of the solid-state image sensor 15.
A so-called focal plane shutter is formed, which covers an exposure screen consisting of a light-receiving surface that can be opened and closed with respect to the exposure optical path. In the exposure optical path between the photographing lens 14 and the solid-state image sensor 15, a half mirror 16 is arranged at an angle of 45 degrees with respect to the optical path, and the object light reflected by this half mirror 16 is A part of the light is incident on a light receiving element 17 for photometry placed below the mirror 16. Further, a diaphragm device is provided in the photographic lens 14. This diaphragm device includes two diaphragm blade members 18 and 19 each having a sickle-shaped diaphragm blade 18a and 19a formed at one end, and whose fulcrums are pivotably pivoted coaxially to a support shaft 21; An ammeter 23 for controlling the diaphragm in which an diaphragm drive pin formed by the tip of the pointer 22 is commonly fitted into oblique elongated holes 18b and 19b formed in the other arm ends of the diaphragm blade members 18 and 19, respectively. It is made up of.

Electromagnet 5 for electromagnetic release, electromagnet 7 for electric shutter, motor 1 for shutter charge
3. The solid-state image sensor 15, the photometric light receiving element 17, and the aperture control ammeter 23 are connected to a control circuit 24, which also has a shutter release button 25 (see FIG. 2). ) is connected to a command switch 26 for scanning second exposure photography and a command switch 27 for shutter second exposure photography, which are closed in conjunction with the depression of the button . As shown in FIG. 2, the shutter release button 25 is fitted into a through hole drilled in the top plate 28 of the camera, and is disposed between the button 25 and the stationary member 29. An extensible coil spring 31 inserted therein gives it the habit of sliding upward. The sliding of the button 25 due to this habit is caused by the flange 25 formed by the outwardly protruding edge of the lower end of the button 25.
a is regulated by abutting against the downwardly protruding opening edge of the through hole of the upper plate 28. The command switch 26 for scanning second exposure photography is formed of a normally closed leaf spring switch, and the tip of one movable contact piece extends to a position where it engages with the upper surface of the flange 25a. It is arranged directly below the upper plate 28 as shown in FIG. Further, the shutter second exposure photography command switch 27 is formed of a normally open leaf spring switch until the tip of one movable contact piece can engage with the lower surface of the flange 25a. It is arranged below the command switch 26 so as to extend. Furthermore, at a position facing the command switch 27 with the spring 31 in between, the tip of a leaf spring member 32 having strong elasticity extends, and this leaf spring member 32 is connected to the shutter release button 25
This is to differentiate between a first stroke and a second stroke in the pressing operation of the button 25 by requiring strong force to press the button 25 halfway when the button 25 is pressed down. Button 25 with spring 3
During the first stroke in which the button 25 is pressed down against the elasticity of the spring 31 and the leaf spring member 32, the command switch 26 closes due to its own elasticity, and during the second stroke in which the button 25 is pressed down against the elasticity of the spring 31 and the leaf spring member 32. During the stroke, the command switch 26 is closed by the collar 25a.

The leading blade member 2 is configured such that, when the leading blade 2a is in the operating position, the upper end surface of one arm abuts against the stopper pin 33, thereby preventing further rotation. Further, the trailing blade member 3 is configured such that the upper end surface of one arm of the trailing blade member 3 abuts against a regulating pin 34 planted in one arm of the leading blade member 2 in the operating position of the trailing blade 3a. , further rotation is now restricted.

As described above, a camera shutter device using the solid-state image sensor of the present invention is configured.

Next, the operation of this shutter device will be explained.

In the normal state shown in FIG. 1 in which the shutter release button 25 is not pressed, the electromagnet 5 for the electromagnetic release
And the electric shutter electromagnet 7 is not energized, so the leading blade member 2 rotates clockwise around the support shaft 1 due to the elasticity of the spring 8.
It collides with the stopper pin 33 and stops at the operating position, and the trailing blade member 3 is at a position where it extends horizontally toward the left (hereinafter referred to as the 180° position).
The cam surface 3b is brought into contact with the movable pin 11 set on the rotary arm 12 which is stopped at the charge position. Therefore, the focal plane shutter consisting of the leading blade 2a and the trailing blade 3a is open, and the subject light passes through the photographic lens 14 and enters the exposure screen formed by the light receiving surface of the solid-state image sensor 15. and the subject image is formed. The subject image formed on this exposure screen is monitored through a viewfinder (not shown). Further, a part of the subject light that has passed through the photographic lens 14 is reflected by the half mirror 16 and is incident on the photometric light receiving element 17. The control circuit 24 determines the subject brightness based on the output of the photometric light receiving element 17, and supplies a current to the aperture control ammeter 23 so that the aperture aperture is controlled to an aperture value that matches the subject brightness. ing. That is, the ammeter 23
receives this current and causes the pointer 22 to swing, and the elongated hole 1
Aperture blade members 18a, 1 via 8b, 19b
The aperture opening formed by the aperture blades 18a and 19a is properly controlled by rotating the aperture member 9a.
Therefore, the subject image formed on the exposure screen is a properly exposed image.

When the shutter release button 25 is pressed in this normal state, the first stroke causes the command switch 26 for scanning second exposure photography to close. When the command switch 26 is closed, the control circuit 24
A control signal is supplied to the solid-state image sensor 15 and a scanning circuit of the element 15 (not shown) to read an image signal for one frame and write this image signal to a magnetic recording means (not shown). Therefore, without using a shutter, one frame's worth of photographs can be taken in the scanning second exposure photography mode, which obtains an image of the subject equivalent to that exposed in the shutter seconds required for scanning the solid-state image sensor 15. This means that

In addition, if it is desired to finish the photographing with one frame worth of photographing by the above-mentioned scanning second exposure photographing, it is sufficient to remove the pressing force from the shutter release button 25 at the stage of the first stroke. In this way, the shutter release button 25 is returned to the non-depressed position by the elasticity of the spring 31, the command switch 26 is opened, and the command switch 2 for shutter second exposure photography is released.
7 is never closed, so there is no transition to shutter second exposure photography, which will be described next.

Next, in order to perform shutter second exposure photography using a shutter, the shutter release button 25 must be pressed against the elasticity of the leaf spring member 32, spring 31, etc. from the first stroke stage after the scanning second exposure photography is completed. Then press down further with strong force. In this way, the command switch 2 for shutter second exposure photography
7 is closed, the control circuit 24 starts supplying drive current to the shutter charge motor 13, and rotates the motor 13 clockwise. Then, the rotating arm 12 rotates clockwise, the movable pin 11 moves while pushing up the other arm end of the leading blade member 2, and the blade member 2 moves around the support shaft 1 against the elasticity of the spring 8. and rotated. Therefore, the front curtain blade 2a moves downward, so that the light receiving surface of the solid-state image sensor 15 is gradually covered with the front curtain blade 2a, and the exposure screen is gradually blocked.
Note that when the moving pin 11 moves and the leading blade member 2 rotates, the trailing blade member 3 is not rotated because the partially arcuate cam surface 3b is brought into contact with the moving pin 11. Then, the rotating arm 12
When rotated to the 90° position shown in FIG. 3, the exposure screen is completely shielded by the front curtain blade 2a, and the suction piece 4 comes into contact with the electromagnet 5. Therefore, the control circuit 24 starts energizing the electromagnets 5 and 7, causes the electromagnets 5 and 7 to attract the adsorption pieces 4 and 6, and moves the leading blade member 2 and the trailing blade member 3 to the charge position, respectively. hold it. Therefore, even if the rotating arm 12 rotates further and the pin 11 escapes from the engagement position between the leading blade member 2 and the trailing blade member 3, as shown in FIG. The trailing blade member 3 refers to the electromagnets 5 and 7.
to maintain a charged state.
When the rotary arm 12 rotates to the 0° position shown in FIG. 4, the control circuit 24 cuts off the power to the motor 13 and stops the motor 13.

On the other hand, the control circuit 24 determines an appropriate aperture value and shutter speed by a program based on the subject brightness measured by the light receiving element 17, and controls the ammeter 23 so that the appropriate aperture value is obtained. Provides control current. The ammeter 23 receives this control current and causes the pointer 22 to swing, and the elongated hole 18b
The aperture blade members 18 and 19 are rotated via +19b to control the aperture aperture to a proper aperture value.

Subsequently, the control circuit 24 cuts off the power to the electromagnet 5 for electromagnetic release, and demagnetizes the electromagnet 5.
Therefore, the leading blade member 2, which has escaped the restraint due to the attractive magnetic force of the electromagnet 5, rotates clockwise around the support shaft 1 due to the elasticity of the spring 8, and as shown in FIG. The upper end surface of the holder is brought into contact with the stopper pin 33 and stopped. Therefore, the front curtain blade 2a moves upward and retreats from the exposure optical path shielding position, so that the front surface of the exposure screen, which is the light receiving surface of the solid-state image sensor 15, is opened, and a subject image is formed through the photographing lens 14. imaged. Therefore, the solid-state image sensor 15
starts charging the photoelectric conversion unit corresponding to each picture element with electric charge according to the amount of received light.

When an appropriate shutter time determined based on the subject brightness has elapsed after the electromagnetic release electromagnet 5 was de-energized, the control circuit 24
Next, the power to the electromagnet 7 for the electric shutter is cut off. Then, the trailing blade member 3, which has escaped the restraint by the attractive magnetic force of the electromagnet 7, rotates clockwise around the support shaft 1 due to the elasticity of the spring 9, and as shown in FIG. The upper end surface is brought into contact with the regulating pin 34 and stopped. Therefore, the trailing blade 2a moves upward and enters the exposure optical path, so that the front surface of the exposure screen formed by the light-receiving surface of the solid-state image sensor 15 is closed, and the exposure operation is completed. And after this,
The control circuit 24 supplies a control signal to the solid-state imaging device 15 and the scanning circuit of the device 15 to read out an image signal corresponding to the charge accumulated in the photoelectric conversion unit corresponding to each picture element, and reads out the image signal corresponding to the charge accumulated in the photoelectric conversion unit corresponding to each picture element. The signal is written to the magnetic recording means. Therefore, one frame worth of photography has been completed in the shutter second exposure photography mode in which the exposure time is controlled using the shutter.

Note that the shutter device of the present invention allows continuous shooting in shutter second exposure shooting mode, but if you want to finish shutter second exposure shooting by shooting one frame, press the shutter release button at this point. It is sufficient to remove the pressing force from 25. In this way, the shutter release button 25 is connected to the leaf spring member 3.
2. Since the command switches 26 and 27 are returned to the non-depressed position by the elasticity of the spring 31, etc., the command switches 26 and 27 are opened, and continuous photographing is not performed.

If the shutter release button 25 is still pressed down to the second stroke stage when one frame of photography is completed in the shutter second exposure mode, Continuous shooting continues. first,
The control circuit 24 supplies the motor 13 with a drive current in the opposite direction to the previous one, causing the motor 13 to rotate counterclockwise. Therefore, the rotary arm 12 rotates counterclockwise, the movable pin 11 moves while pushing up the other arm ends of the leading blade member 2 and the trailing blade member 3, and these blade members 2 and 3 move on the support shaft. 1 against the elasticity of springs 8 and 9. When the rotary arm 12 rotates to the 90° position shown in FIG. 3, the adsorption pieces 4 and 6 come into contact with the electromagnets 5 and 7, respectively. 5 and 7 respectively,
These electromagnets 5 and 7 hold the leading blade member 2 and the trailing blade member 3 at the charge position, respectively. Thereafter, the rotary arm 12 continues to rotate further in the counterclockwise direction, and when it has rotated to the 0° position shown in FIG. 4, the control circuit 24 stops the motor 13.

Next, the control circuit 24 cuts off the power to the electromagnetic release electromagnet 5, operates the front curtain blade 2a,
Exposure of the subject image is started on the exposure screen, which is the light-receiving surface of the solid-state image sensor 15. Then, when the same shutter time as that used for photographing the first frame has elapsed, the control circuit 24 cuts off the power to the electric shutter electromagnet 5, operates the rear curtain blade 3a, and ends the exposure operation. Thereafter, the control circuit 24 supplies a control signal to the solid-state imaging device 15 and the scanning circuit of the device 15 to read out the image signal and store it in the magnetic recording means. Therefore, the second frame is photographed in the shutter second exposure photographing mode following the first frame, and the process ends.

In this way, as long as the shutter release button 25 is continued to be pressed to the second stroke stage, the second and subsequent frames are continuously taken in the same manner as the second frame. After the desired number of frames have been continuously photographed, when the pressing force is removed from the shutter release button 25, the button 25 returns to the non-pressed position due to the elasticity of the leaf spring member 32, spring 31, etc. The command switches 26 and 27 are each opened to stop continuous photographing.

Furthermore, when the last frame has been photographed in the shutter second photography mode, the control circuit 24 supplies the drive current to the motor 13 again, and the rotary arm 12
Rotate to the 180° position shown in Figure 1 and stop. When the rotating arm 12 rotates, the electromagnets 5 and 7 are not excited, and the leading blade member 2 is moved to the operating position where it abuts against the stopper pin 33 due to the elasticity of the spring 8, as shown in FIG. Also, the trailing blade member 3 is connected to the movable pin 11 and the cam surface 3 to the cam 11.
b and is stopped at the charge position. Therefore, the focal plane shutter consisting of the leading blade 2a and the trailing blade 3a stops in an open state,
The normal state is restored in which the subject image formed on the exposure screen formed by the light-receiving surface of the solid-state image sensor 15 can be monitored through the viewfinder.

As described above, according to the present invention, the focal plane shutter is composed of a shutter leading blade and a shutter trailing blade, and a shutter opening mechanism that holds the focal plane shutter at an open position of the exposure screen is provided. Since the holding means is provided, it is possible to perform scanning second exposure photography in which one frame is taken per scanning second of the solid-state image sensor without using a focal plane shutter, and solid-state imaging using a focal plane shutter. It is possible to provide a shutter device for a camera using a solid-state image pickup device which is extremely convenient in use and can easily switch between shutter and second exposure photography for exposing an object image to the device with a simple mechanism.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a shutter device of a camera using a solid-state image pickup device showing an embodiment of the present invention, and FIG. Partial sectional views, Figures 3 to 6
Each figure is a perspective view of a main part showing the operating mode of the shutter device shown in FIG. 1 above. 2... Leading blade member, 2a... Shutter leading blade, 3... Trailing blade member, 3a... Shutter trailing blade, 3b... Cam surface, 5... Electromagnet for electromagnetic release, 7... Electricity Shutter electromagnet, 8...
... Shutter opening spring, 9... Shutter closing spring, 11... Moving pin, 12... Rotating arm, 1
3... Shutter charge motor, 15...
Solid-state image sensor.

Claims (1)

[Scope of Claim for Utility Model Registration] A focal plane shutter, which is formed by a shutter leading blade and a shutter trailing blade, and which opens and closes an exposure screen, which is the light receiving surface of a solid-state image sensor, with respect to an exposure optical path; Shutter open holding means for holding the focal plane shutter at a position where the exposure screen is open; and shutter for moving the focal plane shutter to a charge position where the exposure screen is shielded by the shutter leading blade. A shutter device for a camera using a solid-state image sensor, comprising: a charge mechanism; and an electromagnet that holds the focal plane shutter at the charge position.