JPH0122296Y2 - - Google Patents

Description

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

Charge coupled device (Charge Coupled Device)
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. In addition, since VTR cameras continuously repeat scanning of the photoelectric conversion unit every 1/30 seconds, they are generally not equipped with a shutter device, so controlling the amount of exposure to the photoelectric conversion unit is difficult. This is done exclusively by means of a diaphragm.

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, a shutter device that controls the exposure time of the exposure screen has become indispensable for still cameras.
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-mentioned points, the purpose of the present invention is to:
Shutter second exposure photography is performed in which one frame worth of image signals is read out and recorded from a solid-state image sensor, and the exposure time is controlled using the shutter in connection with pressing the second stroke of the shutter release button. An object of the present invention is to provide a camera using a solid-state image sensor, which performs exposure photography.

According to the present invention, the first button of the shutter release button
Since scanning second exposure photography is performed when the stroke is pressed, and shutter second exposure photography is performed when the second stroke is pressed, the photographer can normally perform scanning second exposure photography and then adjust the shutter speed as needed. You can perform shutter second exposure photography. Therefore, during normal use, unnecessary shutter movements are not added to the photographing operation, and photographs are taken purely electrically, so there is no risk of missing a shutter shot. Additionally, you can operate the shutter as needed to take photos at both high-speed and low-speed shutter speeds.

Furthermore, prior to shutter second exposure photography,
Scanning second exposure photography is always performed, so if you take a high-speed shutter second exposure photograph of a fast-moving subject (for example, a golf swing), you will also be able to avoid blurring from scanning second exposure photography. By comparing the two photographs, you can better understand the movement of the subject.
The magnetic disk used to record images is
It is recyclable and can be used again, so even if you take photos twice as described above, the film will not be wasted unlike cameras that use roll film.

Furthermore, if the camera of the present invention is program-controlled based on photometry of the subject brightness,
In the case of high-speed shutter second exposure photography, the aperture is opened more than in scanning second exposure photography, so it can cope with low light levels during high-speed shutter second exposure photography.
In the case of slow shutter second exposure photography, the diaphragm is closed more than in scanning second exposure photography, so effects such as being able to take pictures even in bright places can be obtained. That is, the dynamic range of subjects that can be photographed is expanded. Another advantage is that manual operations for exposure are not required.

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

FIG. 1 shows the main parts of a camera using a solid-state image sensor according to the present invention. A solid-state image sensor 15 that converts an image into an electrical signal, a shutter device that opens and closes the exposure screen formed by the light-receiving surface of the solid-state image sensor 15 with respect to the exposure optical path, that can control the shutter speed, and that can control the aperture aperture. an aperture device, the solid-state image sensor 15, a shutter device,
A control circuit 24 that controls the operation of the aperture device, etc.
Its main parts are composed of:

The shutter device is swingably supported on a support shaft 1, and has a shutter leading blade 2a at one end.
A thin plate-shaped leading blade member 2 is formed with a thin plate-shaped leading blade member 2, which is also rotatably supported on the support shaft 1 coaxially with the leading blade member 2, and has a shutter trailing blade 3a at one end thereof. The formed thin plate-like trailing blade member 3
and an electromagnet 5 for electromagnetic release that attracts the attraction piece 4 attached to the other arm end of the leading blade member 2.
, an electric shutter electromagnet 7 for attracting a suction piece 6 attached near the other arm end of the trailing blade member 3; and an electric shutter electromagnet 7 having one end attached to one arm of the leading blade member 2, A shutter release spring 8 made of a compressible coil spring that gives the blade member 2 the habit of rotating clockwise around the support shaft 1, and one end of which is attached to one arm of the trailing blade member 3. , a shutter closing spring 9 made of a compressible coil spring that gives the trailing blade member 3 the habit of rotating clockwise around the support shaft 1; Partial arc-shaped cam surface 3 formed on the lower surface
The moving pin 11 that engages with b, and this moving pin 11
The rotary arm 12 is fixedly attached to the free end thereof, and the shutter charge motor 13 is fixedly attached to the output shaft 13a at the base of the rotary arm 12.

The leading blade 2a of the leading blade member 2 and the trailing blade 3a of the trailing blade member 3 extend to a position in front of the solid-state image sensor 15 disposed near the focal plane of the photographing lens 14. It forms a so-called focal plane shutter that covers the exposure screen formed by the light-receiving surface of the solid-state image sensor 15 so as to be openable and closable with respect to the exposure optical path. The above photographic lens 14
A half mirror 16 is arranged in the exposure optical path between the camera and the solid-state image sensor 15 at an angle of 45 degrees with respect to the optical path, and a part of the subject light reflected by the half mirror 16 is , the light is incident on a light receiving element 17 for photometry disposed below the mirror 16. Further, the aperture device is disposed in the photographic lens 14. This aperture device has sickle-shaped aperture blades 18a and 19a at one end.
are formed, respectively, and the two aperture blade members 18 are pivotally mounted coaxially to the support shaft 21 so as to be able to freely swing.
19, and an aperture control pin in which an aperture drive pin, which is the tip of a pointer 22, is commonly fitted into diagonal elongated holes 18b and 19b formed in the other arm ends of the aperture blade members 18 and 19, respectively. It is composed of an ammeter 23.

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 the control circuit 24, which further includes a shutter release button 25 (see Fig. 2). A command switch 26 for scanning second exposure photographing and a command switch 27 for shutter second exposure photographing, which are closed in conjunction with the pressing of the button (see FIG. 1), are connected to each other. The shutter release button 25 is
As shown in FIG.
An extensible coil spring 31 inserted between the stationary member 29 and the stationary member 29 gives it the ability to slide upward. In normal life, the sliding movement of the button 25 due to this habit is regulated by the flange 25a, which is the outwardly projecting edge of the lower end of the button 25, coming into contact with the downwardly projecting opening edge of the through hole of the top plate 28. There is. 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, the command switch 27
A tip of a leaf spring member 32 having strong elasticity extends out from a position facing the spring 31, and when the shutter release button 25 is pressed down, the leaf spring member 32 is released halfway. Button 2
Press button 25 so that it requires strong strength to press button 5.
This is to differentiate between the first stroke and the second stroke in the pressing operation. During the first stroke in which the button 25 is pressed down against the elasticity of the spring 31, the command switch 26 closes due to its own elasticity, and the button 25 is pressed down against the spring 31 and the leaf spring member 3.
During the second stroke of pushing down against the elastic force of 2, the command switch 26 is closed by the flange 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 using the solid-state image sensor of the present invention is configured.

Next, the operation of this camera will be explained.

In the normal state shown in FIG. 1 where the shutter release button 25 is not pressed, the electromagnet 5 for electromagnetic release
The electric shutter electromagnet 7 is not energized, and therefore, the leading blade member 2 rotates clockwise around the support shaft 1 due to the elasticity of the spring 8 and collides with the stopper pin 33. The trailing blade member 3 is mounted on the rotating arm 12 which is stopped at a position extending horizontally toward the left (hereinafter referred to as the 180° position). The cam surface 3b is brought into contact with the movable pin 11, and 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 that has passed through the photographing lens 14 is incident on the exposure screen formed by the light receiving surface of the solid-state image sensor 15. , a 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 18, 19 via 8b, 19b
is rotated to appropriately control the aperture aperture formed by the aperture blades 18a and 19a. 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, it is possible to take one frame's worth of photographs in the scanning second exposure photography mode, which obtains an image of the subject surface equivalent to that exposed in the shutter seconds required for scanning the solid-state image sensor 15. It has been done.

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,
The motor 13 is rotated 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 leading blade 2a moves downward,
The light-receiving surface of the solid-state image sensor 15 gradually changes to the front curtain blade 2a.
The exposure screen is gradually obscured. 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. When the rotary arm 12 rotates 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,
The electromagnets 5 and 7 attract the attraction pieces 4 and 6 to hold the leading blade member 2 and the trailing blade member 3 at the charge position, respectively. 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 is held by electromagnets 5 and 7 to maintain a charged state. and,
When the rotating 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, causes the pointer 22 to swing, and the elongated hole 18
The aperture blade members 18 and 19 are rotated via the aperture apertures b and 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 camera of the present invention allows continuous shooting in the shutter second exposure shooting mode, but if you want to finish the shutter second exposure shooting by shooting one frame, press the shutter release button 25 at this point. All you have to do is remove the pressing force from. In this way, the shutter release button 25 is connected to the leaf spring member 32 and the spring 3.
It returns to the non-pressed position due to the elasticity of the first class, so
Command switches 26 and 27 are each 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 are energized 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 formed by the light-receiving surface of the solid-state image sensor 15. Then, when the same shutter time as when shooting 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 on the shutter release button 25 is removed, 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. Further, the trailing blade member 3 is stopped at the charge position with the cam surface 3b abutting the movable pin 11. Therefore, the focal plane shutter consisting of the leading blade 2a and the trailing blade 3a stops in an open state, and the subject image formed on the exposure screen formed by the light receiving surface of the solid-state image sensor 15 is monitored through the viewfinder. Return to a normal state where you can.

As described above, according to the present invention, in connection with pressing the first stroke of the shutter release button, scanning second exposure photography is performed in which a photograph is taken by scanning the solid-state image sensor, and the shutter release button is pressed. In connection with pressing the second stroke, the shutter is activated to perform shutter second exposure photography in which the solid-state image sensor is exposed to the subject image, so normally constant exposure is performed by scanning the solid-state image sensor Second-time scanning second-exposure photography is performed, and high-speed shutter second-exposure photography is performed as necessary.
It is possible to provide a camera using a solid-state image sensor that is extremely convenient to use and can perform low-speed shutter second exposure photography.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a camera using a solid-state image pickup device showing an embodiment of the present invention, and FIG. 2 is a main part showing the arrangement of the photographing command switch shown in FIG. 1 above. The sectional views and FIGS. 3 to 6 are perspective views of essential parts showing the operating mode of the shutter device shown in FIG. 1, respectively. 2... Leading blade member, 2a... Shutter leading blade, 3... Trailing blade member, 3a... Shutter trailing blade, 5... Electromagnet for electromagnetic release, 7...
Electromagnet for electric shutter, 15... Solid-state image sensor, 17... Light receiving element for photometry, 18, 19... Aperture blade member, 18a, 19a... Aperture blade, 23
...Aperture control ammeter, 24...Control circuit.

Claims (1)

[Claims for Utility Model Registration] A shutter device that opens and closes an exposure screen, which is a light-receiving surface of a solid-state image sensor, with respect to an exposure optical path and that can control the shutter speed, and an aperture device that can control the aperture aperture. In a camera using a solid-state image sensor, Hirao left the shutter device open,
In connection with pressing the first stroke of the shutter release button, scanning second exposure photography is performed by reading and recording one frame worth of image signals from the solid-state image sensor, and the second stroke of the shutter release button The shutter device is characterized in that, in connection with the pressing of the button, after the shutter device is closed, the shutter device is activated to expose the subject image on the exposure screen, thereby performing shutter second exposure photography. A camera that uses a solid-state image sensor.