JP2000122112A - Device for detecting wheter shutter is open/closed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect whether a shutter blade is actually open/closed. SOLUTION: An IRED 20 for emitting infrared ray is arranged in front of the shutter blade 18a, and an infrared ray receiving part 30 is arranged in a camera body 2 to which a lens unit 5 is loaded. While a shutter aperture is formed by the shutter blade 18a, the infrared ray emitted from the IRED 20 is reflected by a photographic film 24 and received by the infrared ray receiving part 30, while the shutter aperture is closed, the infrared ray is not received by the infrared ray receiving part 30. Whether the shutter blade is opened in operation of exposing, or the shutter blade is closed after exposing is discriminated, based on the presence or absence of the reception of the infrared ray at the part 30 during/after the exposing process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shutter open / close detecting device, and more particularly to a shutter open / close detecting device for detecting the open / close state of a shutter blade.

[0002]

2. Description of the Related Art In a shutter device used for a camera,
Since the opening and closing operations of the shutter blades are fast, the control is performed in an open loop. Some of such shutter devices output various signals. For example, an exposure start signal indicating that the opening operation of the shutter blade has been started or a synchronizing signal indicating that the shutter blade has been fully opened. Various signals such as signals are output. For example, the exposure start signal is used for timing for measuring the shutter time, and the synchro signal is used for synchronization of strobe light emission. These signals such as the exposure start signal and the synchro signal are generated by detecting the operation and position change of the shutter blade, a member for driving the shutter blade, a member driven in conjunction with the shutter blade, and the like. .

[0003] For example, Japanese Patent Application Laid-Open No. 8-208157,
In JP-A-6-258688, the shutter blades of the focal plane shutter are extended in a direction perpendicular to the traveling direction, and the variation of the exposure time is determined based on the result of detection of the extended portion by a photo reflector. Judgment and timing of shutter time are performed. In another embodiment of JP-A-8-208157, a phototransistor is disposed behind an extended portion of a shutter blade instead of using a photoreflector, and a phototransistor is provided based on whether or not subject light is received by the phototransistor. Judgment of variations in exposure time and measurement of shutter time are performed.

On the other hand, there is provided a shutter opening / closing detecting device for detecting the opening / closing state of the shutter blade using signals from the shutter device such as the exposure start signal and the synchro signal as described above. 2. Description of the Related Art There is known a camera in which a warning is displayed when an abnormality occurs in an open / close state of a shutter opening such as an open state or a closed state.

[0005] For example, in Japanese Patent Application No. 8-268157, when a plurality of shutter blades of a lens shutter completely closes a shutter opening, a mechanical switch is operated by a part of one of the shutter blades. When pressed and turned on, and the shutter blades open to expose the shutter opening, the pressure is released and turned off. The switch linked to the shutter blade detects that the shutter blade is erroneously opened.

[0006]

By the way, the opening / closing operation of the shutter blade is detected by utilizing the operation and the position change of the member for driving the shutter blade, the member driven in conjunction with the shutter blade, and the like. Then, even when the shutter blade does not actually perform the opening and closing operation, a member for performing the opening and closing operation of the shutter blade or a member that is driven in conjunction with the opening and closing operation of the shutter blade operates to operate the shutter. It may be erroneously detected that the shutter opening is opened by the blade, or it may be erroneously detected that the shutter opening is closed even if the shutter blade is not closed. Therefore, there is a problem in that even if a warning is issued to the photographer when the operation of the shutter device is detected by such a shutter opening / closing detection device, the warning is not normally performed.

Further, it is theoretically possible to directly detect the actual open / closed state of the shutter blade by incorporating a detection unit including a switch, a sensor, and the like into the shutter device as in the cameras described in the above publications. Is possible. However, in the case where a lens shutter incorporating a shutter device is used in the taking lens, an extra space for incorporating the detection unit in the housing holding the taking lens is required, or the assembling space cannot be secured, or This is practically difficult because, for example, the size of the shutter blades must be increased in order to detect the error. Further, in the device disclosed in Japanese Patent Application No. 8-268157, the switch is turned on and off by the shutter blade itself.
Although the FF is performed, this may not always be linked to the open / closed state of the shutter opening. That is, for example, even if the switch is turned on by the shutter blade, the other shutter blades do not operate and the shutter opening remains open, or the shutter mounting position is completely closed due to an error in the mounting position of the switch and the switch is closed before the switch is opened. May be turned ON.

Further, in a camera using an interchangeable photographing lens using a lens shutter, there is a problem that the number of signal lines for transmitting a signal for detecting the movement of the shutter blade from the photographing lens to the camera body increases. . Further, in a camera utilizing subject light, such as the camera described in Japanese Patent Application No. 8-268157, the subject light may not enter the phototransistor at the time of photographing a night scene or the like. It may not be possible to detect whether the shutter opening is open.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a simple structure and a space-saving shutter opening / closing method capable of detecting the opening / closing state of a shutter blade in accordance with the actual opening / closing of a shutter opening. It is an object to provide a detection device.

[0010]

According to a first aspect of the present invention, there is provided a photographic film provided in front of a shutter blade of a lens shutter for controlling exposure of a photographic film. An infrared light emitting diode that outputs infrared light having no sensitivity, and an infrared light emitting diode that is provided at a position behind an optical path of subject light for exposing a photographic film behind the shutter blade, while the shutter blade is opened. An infrared light receiving unit that receives infrared light from the infrared light emitting diode emitted behind the shutter blade, and detects an open / closed state of the shutter blade based on whether or not the light receiving element receives infrared light. It was made. According to the second aspect of the present invention, the infrared light receiving section receives infrared light from the infrared light emitting diode through the shutter opening while the shutter blade is open.

According to the third aspect of the present invention, the infrared light receiving portion is directed to the photographic film so as to receive the infrared light reflected from the photographic film from the infrared light emitting diode. Further, in the invention according to claim 4, the infrared light receiving portion is directed to the photographing lens, and the infrared light emitted from the infrared light emitting diode emitted behind the shutter blade is directly received.

According to a fifth aspect of the present invention, the shutter device is a lens shutter incorporated in a taking lens. According to a sixth aspect of the present invention, the photographing lens is of a replaceable type that is detachable from the camera body, and an infrared light receiving section is provided on the camera body.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 showing a cross section of a main part of a camera embodying the present invention, and FIG.
The camera 2 includes a camera body 3, a film holder 4 attached to the back side of the camera body 3, and a lens unit (photographing lens) attached to the front side of the camera body 3.
5 and a waist-level finder 6 attached to the upper part of the camera body 3 and the like.

The camera main body 3 comprises a box-shaped main body 8 in which a mirror mechanism, a control circuit and the like are incorporated, and a focus adjusting mechanism 9 provided below the main body 8. Openings 10 and 11 are provided on the front side and the back side of the main body 8, respectively.
Are formed. A bellows 13 for blocking the photographing optical path is attached between the front opening 10 and the lens board 12 constituting the focus adjustment mechanism 9. The film holder 4 is attached to the opening 11 formed on the back side of the main body 8 so as to face the opening.

A lens unit 5 is mounted on the front surface of the lens board 12 and is locked by a lock lever 15 provided on the upper part of the lens board 12. The lens unit 5 is provided with various focal lengths, and these can be exchanged and used as needed. The lens unit 5 includes a photographing optical system (lens) 16
A diaphragm device 17, a shutter device 18, an EEPROM 19 (see FIG. 4) for storing the number of operations of the shutter device 18, and an IRED (infrared light emitting diode) 20 are incorporated.

The aperture device 17 comprises an aperture blade 17a and an actuator 17b for driving the aperture blade 17a. An aperture value is set by operating an aperture lever 17c provided on the outer periphery of the lens unit 5. The aperture device 17 has an aperture opening formed by the aperture blades 17a at the time of non-photographing, and is stopped down so as to form an aperture having a magnitude of an aperture value set at the time of photographing.

The shutter device 18 includes a shutter blade 18a.
And an actuator 18b, which is a lens shutter incorporated in the lens unit 5.
The actuator 18 b includes a motor, a magnet, and the like, and receives a control signal from the main body 8 to set the shutter blade 1 at the shutter time set on the main body 8 side.
8a is opened and closed. The shutter blade 18a is formed of, for example, a plurality of shutter blades and swings by an actuator 18b to form a shutter opening. The shutter blade 18a swings between a fully open position where the diameter of the shutter opening is maximized and a shielding position where the shutter opening is closed (disappeared).

The shutter blade 18a is in a fully open position when not photographing, and subject light having passed through the photographing optical system 16 passes through the lens board 12, the bellows 13, and the opening 10, and enters the main body 8. Further, at the time of photographing, the shutter blade 18a is once swung to the shielding position, is set to the fully opened position, and returns to the closed position again after a time corresponding to the set shutter time. Thereby, one photographing is performed. After shooting, the shutter blades 18a
The fully opened position is set again. The shutter device 18 is charged by the operation when the shutter blade 18a swings from the shielding position to the fully open position.

In this example, the shutter device is a behind-the-lens shutter disposed behind the photographing optical system 16, but it may be a between-the-lens shutter or a before-the-lens shutter. In this example, the shutter blade itself forms the shutter opening, but the shutter blade may open and close a shutter opening provided separately from the shutter blade.

On the rear side of the lens unit 5 and on the front side of the lens board 12, there are provided contact points 21 for electrically connecting the components of the lens unit 5 to a control circuit and a power supply circuit incorporated in the camera body 3. 22 are provided. The lens board 12 and the camera body 3 are electrically connected by a flexible cord 23.

The IRED 20 is a part of a shutter opening / closing detection device for detecting the actual opening / closing state of the shutter blade 18a, and outputs infrared rays in a wavelength range where the photographic film 24 has no sensitivity. This IRED 20 is a shutter blade 18
The infrared rays output from the photo film reach the shutter blade 18a, and the infrared rays enter the photographic film 24 while the shutter opening is formed, and the shutter opening is completely closed. In this case, infrared rays are not emitted from the shutter device 18 to the rear (the film side).

In this example, the IRED 20 is arranged so as to illuminate the front surface of the photographing optical system 16 with infrared rays, and the infrared rays refracted and reflected by the photographing optical system 16 enter the photographic film 24 through the shutter opening. But IR
If the ED 20 is disposed forward of the shutter device 18 and infrared rays can be emitted backward through the shutter opening formed by the shutter blades 18a, the IRED 20
May be arranged in other forms.

The IRED 20 is lit by receiving power supplied from the power supply circuit of the camera body 3 via the contact portions 21 and 22. As a result, the IRED 20 is continuously lit while the power of the main unit 8 is ON while the lens unit 5 is mounted on the lens board 12.

In the main body 8, an opening 11 on the back of the main body 8 is provided.
A light-shielding plate 25 that closes the opening 11 in a light-tight manner and a mirror 26 that changes the optical path of subject light are arranged in front of. As shown in FIG. 1, the light-shielding plate 25 and the mirror 26 are arranged so that the light-shielding plate 25 closes the opening 11 and the mirror 26 transmits the subject light from the lens unit 5 to the main body around the shaft attachment portion 27 as shown in FIG. 8 is rotatable between a DOWN position that reflects upward and a UP position that rotates clockwise in FIG. At the time of non-photographing, the light shielding plate 25 and the mirror 26 are in the DOWN position to shield the inside of the film holder 4 and at the time of photographing, are turned to the UP position to allow the subject light and the infrared light from the IRED 20 to be opened.
Allowed to pass through.

A focusing glass 28 is fitted on the upper surface of the main body 8, and the subject light reflected by the mirror 26 at the UP position is focused on the focusing glass 28. As shown, a focus glass 28 is provided on the upper surface of the main body 8.
A foldable waist level finder 6 that makes it easy to see from above, an AE finder (not shown) having an automatic exposure function, and the like are mounted according to shooting conditions and applications.

The AE finder is a focus glass 2
A viewfinder optical system equivalent to an angle finder that bends the subject light imaged on 8 so that it can be viewed as an erect image, and a light receiving element that measures the brightness of the subject light imaged on the focus glass 28 An AE finder control circuit for driving the light receiving element, determining a shutter time based on a photometric value of the light receiving element and an aperture value set by the lens unit 5, and inputting the shutter time to a control circuit of the camera body 3. And so on. Although not shown, contact points for electrically connecting an AE finder control circuit to a control circuit and a power supply circuit in the camera body 3 are provided on a lower portion of the AE finder and an upper surface of the main body 8, respectively.

In the bottom of the main body 8, the aforementioned IRE is provided.
An infrared light receiving unit 30 constituting a shutter opening / closing detection device together with D20 and a subject light receiving unit 31 for exposure monitoring (see FIG. 4) are arranged. Each of the light receiving units 30 and 31 and the supporting members that support them are arranged at a position that is used for photographing from the lens unit 5, that is, a position outside the optical path of subject light that exposes the photographic film 24.

The infrared light receiving section 30 is composed of, for example, a condenser lens, a filter transmitting only infrared light, and a phototransistor having sensitivity to infrared light, and is directed to the photographic film 24 through the opening 11. The infrared light reflected by the photo film 24 is received. Thereby, while the light shielding plate 25 and the mirror 26 are in the UP position,
When the shutter blade 18a forms a shutter opening, infrared light from the IRED 20 is reflected by the photographic film 24 and received by the infrared light receiving unit 30. Based on the presence or absence of infrared rays by the infrared light receiving unit 30, whether the shutter blade 18a is actually opened or closed, that is, the actual open / closed state of the shutter blade 18a is detected.

The open / closed state of the shutter blade 18a is detected using the IRED 20 provided on the lens unit 5 and the infrared light receiving unit 30 provided on the main body 8 side. Since the infrared light from the IRED 20 is received by the infrared light receiving unit 30 built in the main body 8, the shutter blade 1
It is not necessary to provide a contact for inputting and outputting a signal indicating the open / close state of the lens unit 8a to the lens unit 5 and the camera body 3. Also,
As described above, since the IRED 20 is turned on by supplying power to the lens unit 5, it is not necessary to provide a power supply contact. Further, the lens unit 5 includes an IRED2
Only zeros need to be embedded, requiring little embedded space.

It is also possible to detect the actual exposure value EV determined from the aperture value and the shutter speed by using the IRED 20 for detecting the open / closed state of the shutter blade 18a and the infrared light receiving unit 30. However, when photographing is performed using natural light, the subject light is affected by the infrared light because the light includes the infrared light. Therefore, in practice, its use range is limited.

The subject light receiving section 31 for the exposure monitor has the same configuration as the infrared receiving section 30.
4 is designed to receive only light in a wavelength range having sensitivity by a phototransistor or the like. This subject light receiving section 3
1 detects the amount of exposure of the subject light to the center of the photographing frame of the photographic film 24, detects the variation of the actual exposure with respect to the standard exposure value, and when this variation is large, warns the photographer. Will be

It is possible to detect the open / closed state of the shutter blade 18a based on the result of light reception by the subject light receiving unit 31, but in the case of shooting in a night scene or darkness,
When the subject is not at the center, or when flash photography is performed, the subject light receiving unit 31 does not receive the subject light even when the shutter blade 18a forms the shutter opening, or only while the flash is emitting light. Subject light may be received. Therefore, regardless of the shooting conditions,
In order to be able to detect the open / closed state of the shutter blade 18a,
As described above, it is necessary to provide the IRED 20 and the infrared light receiving unit 30. That is, as described above, IRED2
0 and the infrared light receiving unit 30, the shutter blade 18a
The open / closed state of the shutter blade 18a can be accurately detected even when the subject is not in the center and flash photography is performed in night scenes or darkness.

On one side of the main body 8, a film winding doubles as a shutter speed adjusting dial 33 for switching between shutter speed and AE mode, and a main power switch for turning on / off the power of the camera 2. A mode switching dial 34 for switching the mode, a mirror up switch 35 for forcibly rotating the light shielding plate 25 and the mirror 26 in the main body 8 to the UP position, an operation panel 37 to which a release switch 36 and the like are attached are provided. ing. In addition, a liquid crystal display (LC) that displays a camera state such as whether or not photographing is possible and a warning and an error display such as remaining battery power and abnormal exposure are provided on the upper surface of the main body 8 beside the focus glass 28.
D) 38 is provided.

The focus adjusting mechanism 9 includes a base 40 mounted on the lower surface of the main body 8 and a pair of focusing rails 4 protruding forward from the base 40.
1 and a slide portion 42 which is movable along the focusing rail 41 and has the above-mentioned lens board 12 mounted on the upper portion thereof. An operation knob 43 is rotatably attached to the side of the slide portion 42.
When the operation knob 43 is rotated, the slide portion 42 moves along the focusing rail 41, and the camera body 3
Focus adjustment is performed by changing the distance between the lens unit 5 and the lens unit 5.

The lens board 12 is mounted on a frame part 45 mounted on the upper part of the slide part 42. The frame part 45 is slidable and rotatable in a left-right direction orthogonal to the sliding direction of the slide part 42. The lens board 12 is attached to the frame 45 so as to be rotatable in a vertical direction perpendicular to the direction of rotation of the frame 45. Thus, the camera 2 can perform tilt shooting without using any special device.

In the film holder 4, a film loading chamber 50 in which a brownie-size photo film 24 is loaded.
And an aperture 51 for defining an exposure range for the photographic film 24. Various sizes of masks are attached to the aperture 51, and the photographing size can be changed as appropriate. Aperture 5
1, a light-shielding cover 5 for light-tightly shielding the aperture 51 when removing the film holder 4 from the camera body 3.
2 is inserted. The light-shielding lid 52 is removed from the film holder 4 at the time of photographing.

The film holder 4 is used to hold the camera body 3
By rotating the film holder 4 by 90 ° without changing the attitude of the camera 2, the vertical and horizontal directions of the shooting screen can be switched. The display range of the focus glass 26 is also switched between vertical and horizontal in conjunction with the rotation of the film holder 4.

Further, the first frame of the photo film 23 is set in the aperture in the film holder 4, and the photo film 23 is wound up by one frame for each photographing.
Further, a winding mechanism 53 for winding up the entire photo film 23 after photographing all frames is incorporated. Also, the back side of the camera body 3 and the film holder 4 are connected so that the control circuit and the power supply circuit in the camera body 3 can be electrically connected to the control circuit and the power supply circuit in the film holder 4.
Contact portions 54 and 55 are provided on the front side of the device. The contact portions 55 of the film holder 4 are provided at two positions so that they can be connected to the contact portions 54 of the camera body 3 even when the film holder 4 is rotated by 90 °.

On the upper surface of the film holder 4, a liquid crystal display 56 for displaying various information of the loaded photographic film 24 and information of the camera 2 itself, and the total number of shots of each unit are displayed on the liquid crystal display 56. An operation panel 58 provided with a total shot button 57 and the like is provided.

As shown in FIG. 3, the liquid crystal panel 56 includes:
A mask size 60 (for example, 6) representing the size of the mask attached to the aperture 51 of the film holder 4
cm × 8 cm), a film type 61 indicating the type (120 type or 220 type) of the loaded photo film 23, a film sensitivity 62 indicating the sensitivity of the photo film 23, a number display 63 indicating the number of shots, A camera monitor 64 or the like indicating the state is displayed. In the portion where the film sensitivity 62 is displayed, the total shot number, date, time, remaining battery level, and the like of each unit are displayed by operating a total shot button 57 provided on the operation panel 58.

The camera monitor 64 has a mark 66 representing the camera body 3, a mark 67 representing the film holder 4,
A mark 68 representing the lens unit 5 and a mark 69 representing the AE finder 6 are provided. These marks 66 ~
The reference numeral 69 indicates that only the mark 67 is displayed on the liquid crystal panel 56 when the film holder 4 is not attached to the camera body 3 and is a single unit. When the camera body 3 and the lens unit 5 are attached to the film holder 4 and the respective units are electrically connected by the respective contact portions, marks 66, 68, and 69 are displayed on the liquid crystal panel 56. Accordingly, when no mark is displayed on the liquid crystal unit 56 even though the unit is attached to the main unit 3, it can be understood that a contact failure has occurred in the contact portion.

Further, when an operation error occurs in the camera body 3, the film holder 4, the lens unit 5, etc., the corresponding mark on the camera monitor 64 blinks,
The photographer is warned. Thereby, as a result of detecting the open / closed state of the shutter blade 18a at the time of photographing, the shutter blade 18a is detected.
Is not opened at the time of shooting, or is not closed after the exposure is completed, the mark 6 corresponding to the lens unit 5
8 flashes to inform the user.

FIG. 4 is a block diagram showing a circuit configuration of the camera 2. As shown in FIG. Each of the light receiving units 3 described above is provided in the camera body 3.
0, 31, operation panel 37, liquid crystal display 38, mirror mechanism 71, mirror drive circuit 72, EEPROM
M73, shutter monitor circuit 74, exposure monitor circuit 7
6, a drive circuit 77, a synchro contact control circuit 78, a main body power supply circuit 79, and the like.

The camera main body 3 incorporates a main body MPU 80 which is a control circuit for controlling the above circuits and the circuits provided in the lens unit 5 and the AE finder. The main body MPU 80 has a CPU and an RO in which programs for performing various sequences are written.
M, a RAM used as a work memory, a communication circuit for communicating with the film folder 4, and the like.

The mirror mechanism 71 includes a light shielding plate 25, a mirror 2
6, a detection circuit for detecting these operations. The mirror driving circuit 72 drives the motor 72a to drive the light shielding plate 25.
And the mirror 26 swings between the UP position and the DOWN position.
In addition, the number of operations of the mirror mechanism 71 is written in the EEPROM 73.

The shutter monitor circuit 74, which is a part of the shutter opening / closing detecting device, is connected to the infrared light receiving unit 30, and receives a photoelectric signal from the infrared light receiving unit 30.
The shutter monitor circuit 74 sequentially adds the levels of the input photoelectric signals to form the photographic film 24.
IRED 20 reflected by the infrared receiver 30 and received by the infrared receiver 30
Is obtained by integrating the amount of infrared light from
Send to PU80. Based on the integrated value, main body MPU 80 determines whether a shutter opening is formed by shutter blades 18a at the time of photographing, or whether shutter blades 18a are closed and in the shielding position after photographing.

The subject monitor light receiving section 31 is connected to the exposure monitor circuit 75, and a photoelectric signal is input from the light receiving section 31. The exposure monitor circuit 75 integrates the exposure amount of the photographic film 24 by the subject light based on the photoelectric signal from the subject light receiving unit 31 in the same manner as the shutter monitor circuit 74, and calculates the integrated value.
Send to 0. The main body MPU 80, based on this integrated value,
The difference between the exposure amount and the standard exposure amount due to the subject light at the time of shooting is obtained.

The drive circuit 77 outputs various control signals for driving the aperture device 17 and the shutter device 18 of the lens unit 5, and drives them in a predetermined procedure. The control signal for driving the shutter device 18 includes a motor drive signal for setting the shutter blade 18a to the shielding position or the fully open position, an MGE signal output before the start of exposure and stopped at the start of exposure, and an output before the start of exposure. There is an MGK signal that is stopped at the timing when the shutter blade 18a is returned to the shielding position. The motor drive signal is a drive current for driving the motor of the actuator 18b. By reversing the direction of the drive current, the shutter blade 18a is moved from the shield position to the fully open position, or from the fully open position to the shield position. Rocked.

The synchro contact control circuit 78 receives a synchro signal from the shutter device 18a when the shutter blade 18a is fully opened, and turns on the synchro contact portion 78a when this signal is input. In the sync contact portion 78a,
A strobe device is connected. As a result, when the shutter blade 18a is fully opened, flash light is emitted from the flash device. The main body power supply circuit 79 is composed of a battery, a voltage regulator, and the like built in the main body unit 8, supplies power to each circuit of the camera main body 3, and has a film holder 4, a lens unit 5, and an AE finder mounted thereon. In this case, power is also supplied to these.

The film holder 4 includes, in addition to the above-described winding mechanism 53, the liquid crystal display 56 and the operation panel 58, a winding driving circuit 83 including a motor 82 for driving the winding mechanism 53, and gears and the like constituting the winding mechanism 53. A hoist detection circuit 84 for detecting rotation, a holder EEPROM 85 for storing the number of operations of the hoist mechanism 53, a holder MPU 86 as a control circuit for controlling these circuits, and the like are incorporated. When the holder MPU 86 is mounted on the camera body 3, the holder MPU 86 communicates with the body MPU 80,
Each part of the film holder 4 is operated under the control of the main body MPU 80.

The film holder 4 has a holder power supply circuit 87 built therein. This holder power supply circuit 87
Is composed of a battery, a voltage regulator, and the like built in the film holder 4. When the film holder 4 is a single unit, power is supplied to each part of the film holder 4 using the battery built in the film holder 4 as a power source. When the camera is mounted on the camera body 3, power is supplied using the body power supply circuit 79 as a power supply.

The lens unit 5 includes the above-described diaphragm device 1
7, shutter device 18, EEPROM 19, IRED2
0 is built in, and operates by power supply from the main body power supply circuit 79. The shutter device 18 has its actuator 1
8b is driven by a control signal from the drive circuit 77 to open and close the shutter blade 18a. At the time of photographing, in addition to a synchro signal, a SEE signal indicating that the exposure has been completed, a shutter blade 18a
, An SEC signal indicating that the exposure is started, an ST signal indicating that exposure has started, and the like are output. The ST signal is also used to identify the shutter charge state of the shutter device 18. These signals are obtained from the operation of the actuator 18b, and are not obtained based on the actual open / closed state of the shutter blade 18a.

From the lens unit 5, signals such as the open aperture value of the aperture device 17 and the set aperture value are sent to the main body MPU 80. The EEPROM 19 has a main body M
The number of operations of the shutter device 18 is written by the PU 80. In practice, the aperture device 17 is integrated with the shutter device 18.

Next, the operation of the above configuration will be described.
At the time of photographing, a film holder 4, a lens unit 5, an AE finder or a waist level finder 6 in which a photographic film 24 is loaded is attached to the camera body 3.

The photographer operates the mode changeover switch 34 to select one of the winding modes. Then
The main power switch is turned on, and the circuits in the camera body 3 and the body MPU 80 are activated. Power is supplied from the main body power supply circuit 79 to the lens unit 5 and the film holder 4 via the contact portions 22, 21, 54, 55. Of course, when the AE finder is mounted, power is also supplied to the AE finder.

By this power supply, the film holder 4 operates using the main body power supply circuit 79 as a power supply instead of the battery contained therein. In the lens unit 5,
The aperture device 17 and the shutter device 18 become operable, and the IRED 20 is turned on.

When the main body MPU 80 is in the operating state, the main body MPU 80 checks each part of the main body part 8,
Communication is performed with the PU 86, and the presence or absence of the input of each signal from the lens unit 5 is checked to determine whether or not the camera is in a photographable state. When the camera is ready to take a picture, a motor drive signal is sent from the drive circuit 77 and the actuator 1 of the shutter device 18 is turned on.
At 8b, the shutter blade 18a is set to the fully open position. By setting the shutter blade 18a to the fully open position, the shutter device 18 is charged by the shutter.

When taking a picture, the photographer must wear the AE finder or the waist level finder 6
Framing is performed using. Also, the lens unit 5
The aperture value is set by operating the aperture lever 17c, and the shutter speed is set by operating the shutter speed adjustment dial 33. In addition, AE finder is attached, AE
When the mode is selected, the shutter time according to the set aperture value, subject luminance, and film sensitivity is automatically set.

Thereafter, the photographer presses the release button 36 to perform photographing. When the release button 36 is pressed, a sequence for photographing is performed according to the procedure shown in FIG. Note that FIG. 5 shows the procedure of the main part, with some procedures omitted.

When the release button 36 is pressed, the main body MPU 80 first checks the battery of the main body power supply circuit 79. If it is determined by this battery check that the remaining battery level of the camera body 3 is small enough to perform shooting, the liquid crystal display 5 of the film holder 4
6 indicates that the remaining battery level is low, and ends the shooting sequence.

When the battery level is sufficient, the main unit MP
After starting output of the MGE signal and the MGK signal via the drive circuit 77, the U80 transmits the motor drive signal to the actuator 1 to swing the shutter blade 18a to the shielding position.
8b. Thereby, the shutter blade 18a
It is swung to the shielding position by the motor of the actuator 18b, and is held at the shielding position by the magnet driven by the MGE signal.

The main body MPU 80 receives the SEC signal output from the shutter device 18 and
is detected, the motor 72a is driven via the mirror drive circuit 72, and the light shielding plate 2 is driven.
5. The mirror 26 is turned from the DOWN position to the UP position. At the same time, the aperture device 17 is operated via the drive circuit 77, and the aperture blade 17a is stopped down to the aperture value set by the aperture lever 17c.

Thereafter, the main body MPU 80 resets the shutter monitor circuit 74 to set its integral value to "0" and then activates it. As a result, the infrared light from the IRED 20 is reflected by the photographic film 23 and
, The integrated value corresponding to the intensity of the infrared ray and the incident time is output to the main body MPU 80.

After activating the shutter monitor circuit 74,
The main body MPU 80 stops the MGE signal in order to start exposing the photo film 24. When the MGE signal stops, the shutter blades 18a, which have been held at the shielding position in a state where the shutter is charged, are simultaneously swung in the opening direction for forming the shutter opening. When the shutter blade 18a reaches the fully open position, the shutter blade 18
a is held at the fully open position by a magnet driven by the MGK signal. Also, in this manner, the shutter blade 18
When a starts to swing in the opening direction and reaches a predetermined position, the ST signal that has been output in response to the shutter charged state is stopped.

The main body MPU 80 starts counting the shutter time in response to the stop of the ST signal. When the measured shutter time reaches a value corresponding to the set shutter time, the MGK signal is stopped. MG
When the K signal is stopped, the shutter blades 18a held at the fully open position swing at the same time in a direction to reduce the opening diameter of the shutter opening, and return to the shielding position. Shutter blade 18
When “a” returns to the shielding position, a SEE signal is sent from the shutter device 18 to the main body MPU 80 to notify that the exposure has been completed.

As described above, the shutter blade 18a is opened and closed, and while the shutter blade 18a forms the shutter opening, the photographing optical system 16, the aperture opening,
The photographic film 24 is exposed by subject light passing through the shutter opening.

When receiving the SEE signal, main body MPU 80 checks the integrated value output from shutter monitor circuit 74. For example, as described above, the shutter blade 1
When the opening / closing operation of the shutter 8a is normally performed, the IRED is opened while the shutter blade 18a forms the shutter opening.
The infrared light output from 20 reaches the photographic film 24 via the photographic optical system 16, the aperture opening and the shutter opening, and a part of the infrared light that reaches the photographic film 24 is reflected and received by the infrared light receiving unit 30. You. Then, a photoelectric signal is input from the infrared light receiving unit 30 to the shutter monitor circuit 74, and the integrated value of the shutter monitor circuit 74 becomes a value larger than “0”.

As described above, the shutter monitor circuit 74
If the integral value from is larger than “0” (there is an integral value), the main body MPU 80 determines that at least the shutter blade 18a is actually opened, and then the shutter blade 18a It returns to the shielding position and checks whether or not the shutter opening is closed. This includes the main unit MPU80
First resets the shutter monitor circuit 74 to set its integral value to "0", and then performs integration for a certain period of time.

As described above, if the shutter blade 18a is performing the opening / closing operation, at this time, the shutter blade 18a
Is in the shielding position, and the infrared light from the IRED 20 is not received by the infrared light receiving unit 30, so that the integrated value from the shutter monitor circuit 74 becomes “0”.

The main body MPU 80 includes a shutter monitor circuit 7
Since the integrated value from 4 is "0", it is determined that the shutter blade 18a is at the shielding position. Then, based on the result of examining the two integrated values, it is determined that the shutter blade 18a has been opened and closed, and the light-shielding plate 25 and the mirror 26 have been returned to the DOWN position. Send shutter blades 18
Is set to the fully open position, and at the same time, the film is fed, and the next photographing standby state is set.

Whether the shutter blade 18a is open or closed is determined based on the integrated value from the shutter monitor circuit 74. When the shutter blade 18a is opened and closed as described above, the subject light receiving section 31 is opened. And the exposure monitor circuit 75 measures the amount of subject light reflected by the photographic film 24. Based on the measurement result, a deviation of the actual exposure from the standard exposure is detected. If it is large, you will be warned.

By the way, as described above, the driving circuit 7
Even when the control signal from 7 is supplied to the shutter device 18 and the SEC signal, the SEE signal, and the like are returned from the shutter device 18, the shutter blade 18a may not actually perform the opening / closing operation.

In such a case, for example, the shutter blade 18
a is locked to the shielding position and the shutter opening is not formed.
Infrared rays from 0 do not enter the photographic film 24. While the shutter blade 18a is being opened and closed, infrared light is not received by the infrared light receiving unit 30, and the integrated value from the shutter monitor circuit 74 is "0". Therefore, the main body MPU 80
When the integrated value is checked at the first time, that is, immediately after the SEE signal is input, and the integrated value is "0", it is determined that the shutter blade 18a has not formed the shutter opening. Then, when determined in this way, the main body MPU 80
Indicates that the shutter blade 18a has not been opened.
The error flag is stored in the main body MPU 80, and an instruction is given to the holder MPU 86 to display a warning based on the SB error flag. Holder MPU86 is L
The CD 86 is driven to flash the mark 68 on the camera monitor 64 corresponding to the lens unit 5 displayed on the CD 86. Thus, the photographer is warned that the shutter device 18 is abnormal.

On the other hand, when the shutter blade 18a is locked in the open state when the shutter blade 18a is set to the shielding position just before photographing and is not swung to the shielding position, or after the shutter blade 18a shifts from the shielding position to the open state. When the shutter blade 18a is locked and does not return to the shielding position, the shutter blade 18a is open when checking whether the shutter blade 18a has returned to the shielding position. Therefore, at this time, I
The infrared light from the RED 20 is reflected by the photo film 24 and received by the infrared light receiving unit 30, and the integrated value from the shutter monitor circuit 74 becomes larger than "0".

For this reason, when the integrated value at this time is larger than "0", the main body MPU 80 determines that the shutter blade 18a is kept open,
The SB error flag indicating this is stored in the main body MPU 80. Then, based on this SB error flag, an instruction is issued to give a warning display to holder MPU 86. As a result, the mark 68 on the camera monitor 64 blinks to warn the photographer that the shutter device 18 is abnormal.

When the main body MPU 80 determines that the shutter device 18 is abnormal in this way, the light shielding plate 2
5. After returning the mirror 26 to the DOWN position, the photographing is prohibited. The photographing prohibited state is set by the mode switch 3
Operate 4 to turn the main power switch off and on again
Can be reset by resetting the SC error flag or the SB error flag by a power-on reset. However, if the abnormal state of the shutter device 18 has not been eliminated, the photographing can be performed by operating the release button 36 again. , Normal photographing cannot be performed, and photographing is prohibited again.

If the integrated value of the shutter monitor circuit 74 can be checked immediately before the MGE signal is stopped, that is, immediately before the shutter blade 18 is opened, the shutter blade 18a is set to the shielding position before photographing. It is possible to identify whether the shutter blade 18a is locked in the open state, or whether the shutter blade 18a is locked after shifting from the closed position to the open state and does not return to the closed position.

FIG. 6 shows an example in which infrared rays from the IRED are directly received by the infrared ray receiving section.
Note that parts other than those described below are the same as those in the above-described embodiment, and the same components are denoted by the same reference numerals and description thereof will be omitted.

As shown in FIG. 6, an infrared ray receiving section 30 for receiving infrared rays from the IRED 20 is disposed behind the light shielding plate 25, and
8a. FIG. 7 shows the spread of the optical path of subject light emitted from the lens unit 5 as viewed from the lens unit 5 side at the position of the infrared light receiving unit 30 and the infrared light receiving unit 30.
This shows the positional relationship with. The optical path of the subject light emitted from the lens unit 5 has a circular spread at the position of the infrared light receiving section 30 as shown in a region 90, and the light in the optical path of the rectangular region 91 at the center portion is the film holder. 4, and the photographic film 24 is exposed. That is, the subject light in the area 91 is used for shooting.

The infrared light receiving section 30 is arranged in the area 90 described above, but outside the area 91. In other words, they are arranged so as not to block the subject light used for photographing.
Thus, the infrared light output from the IRED 20 and emitted from the lens unit 5 while the shutter blade 18a forms the shutter opening is transmitted to the infrared light receiving unit 30 while the exposure of the photographic film 24 is not affected. To receive light.

In this camera 2, the rotation of the film holder 4 can switch the vertical and horizontal directions of the photographing screen. The infrared light receiving section 30 is arranged so that In addition, since the mask size of the aperture 51 can be changed, the infrared light receiving unit 30 is configured so as not to block the subject light provided for photographing, regardless of which mask is used.

The infrared receiving section 30 may be provided in front of the mirror 26, for example, at a position indicated by reference numeral 93 in FIG. In this way, even when the mirror 26 and the light shielding plate 25 are at the DOWN position, the shutter blade 18
a can be detected. Again, in this case,
It goes without saying that the infrared light receiving unit 30 does not block the subject light provided for photographing.

The IRE is located outside the subject light area 90.
If the infrared rays from D20 are directed, it goes without saying that the infrared ray receiving section 30 may be provided outside the area 90.

In each of the above embodiments, the open / closed state of the shutter blade is determined by integrating the photoelectric signal from the infrared light receiving unit to determine whether or not infrared light is received. It can also be determined by the presence or absence. Also, IRED
Is turned on continuously while the power of the camera is turned on. For example, the IRE is made to respond to the start of the output of the MGE signal for holding the shutter blade at the shielding position.
D may be turned on and, after the photographing is completed, turned off by a motor drive signal for swinging the shutter blade to the fully open position. By doing so, useless power consumption can be suppressed.

In the above description, a system camera in which a lens unit, a film holder and the like are mounted on the camera body has been described. However, the present invention can be used for various cameras such as an instant camera and a compact camera. Further, the shutter device may be a program shutter in which the shutter blade also serves as the aperture blade.

[0086]

As described above, according to the present invention,
In front of the shutter blades of the lens shutter that controls the exposure of the photographic film, an infrared light emitting diode that outputs infrared light that the photographic film has no sensitivity is provided. A light-receiving element that receives infrared light from an infrared light emitting diode that is emitted backward is provided behind the shutter blades at a position off the optical path of subject light that exposes the photographic film to determine whether the light-receiving element receives infrared light. Since the open / closed state of the shutter blade is detected based on this, it is possible to detect the actual open / closed state of the shutter blade while realizing space saving with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a camera.

FIG. 2 is a perspective view showing the appearance of the camera.

FIG. 3 is an explanatory view showing display contents of a liquid crystal panel of a film holder.

FIG. 4 is a block diagram showing an electrical configuration of the camera.

FIG. 5 is a flowchart illustrating a procedure for detecting an open / closed state of a shutter blade.

FIG. 6 is a cross-sectional view of a main part of a camera showing an example in which infrared light from an IRED emitted from a lens unit is directly received by an infrared light receiving unit.

FIG. 7 is an explanatory diagram illustrating a relationship between an infrared light receiving unit and subject light.

[Explanation of symbols]

 2 Camera 3 Camera body 5 Lens unit 18 Shutter device 18a Shutter blade 20 IRED 24 Photo film 30 Infrared light receiving section 74 Shutter monitor circuit 80 Main body MPU

[Procedure amendment]

[Submission date] November 16, 1998 (1998.11.
16)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

[0003] For example, JP 6 -208157, JP-
In JP-A-6-258688, the shutter blades of the focal plane shutter are extended in a direction perpendicular to the traveling direction, and the variation of the exposure time is determined based on the result of detection of the extended portion by a photo reflector. Judgment and timing of shutter time are performed. Further, in another embodiment of JP-A 6 -208157 discloses, instead of using a photo-reflector, by arranging the phototransistor behind the extension of the shutter blade, based on the presence or absence of light reception of the object light by the phototransistor Judgment of variations in exposure time and measurement of shutter time are performed.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005] For example, Japanese Open flat 8-262 intended for 548 JP, some mechanical switch is one of the shutter blade when a plurality of shutter blades of the lens shutter is completely closed the shutter opening When the shutter blade is opened and the shutter opening is exposed, the pressing is released and turned off. The switch linked to the shutter blade detects that the shutter blade is erroneously opened.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

Further, it is theoretically possible to directly detect the actual open / closed state of the shutter blade by incorporating a detection unit including a switch, a sensor, and the like into the shutter device as in the cameras described in the above publications. Is possible. However, in the case where a lens shutter incorporating a shutter device is used in the taking lens, an extra space for incorporating the detection unit in the housing holding the taking lens is required, or the assembling space cannot be secured, or This is practically difficult because, for example, the size of the shutter blades must be increased in order to detect the error. Also, by way of Japanese open flat 8-262 548 JP, switch ON by the shutter blades themselves, OF
However, this may not always be linked to the open / closed state of the shutter opening. That is, for example, even if the switch is turned ON by the shutter blade, the other shutter blades do not operate and the shutter opening remains open,
An error in the mounting position of the switch may cause the shutter opening to be completely closed and the switch to be turned ON before.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

Further, in a camera using an interchangeable photographing lens using a lens shutter, there is a problem that the number of signal lines for transmitting a signal for detecting the movement of the shutter blade from the photographing lens to the camera body increases. . Further, in the case of using the subject light as in another embodiment of Japanese Patent Application Laid-Open No. 6-208157 , the subject light may not be incident on the phototransistor at the time of shooting a night scene or the like. That is, it may not be possible to detect whether or not the shutter opening is open.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Katsuhiko Yamamoto, Inventor Katsuhiko Yamamoto 1-3324 Uetakecho, Omiya City, Saitama Prefecture Inside (72) Inventor Hisashi Hamada, Hisashi Hamada 3-13-45 Izumi, Asaka City, Saitama Prefecture Fuji Photo Within Film Co., Ltd. (72) Inventor Tokuji Sato 3-13-45 Izumi, Asaka-shi, Saitama Fuji Photo Film Co., Ltd. F-term (reference) 2H002 BB05 HA02 HA07 JA02 2H081 AA42 AA51 CC44

Claims (6)

[Claims] 1. A shutter opening / closing detecting device for detecting the open / closed state of a shutter blade of a shutter device for controlling exposure of a photographic film, wherein the infrared light is provided in front of the shutter blade and the photographic film has no sensitivity. And an infrared light emitting diode that outputs light from a subject, and is provided at a position behind an optical path of subject light that exposes a photographic film behind the shutter blade, and is provided behind the shutter blade while the shutter blade is open. An infrared light receiving unit that receives infrared light emitted from the infrared light emitting diode, and detects an open / closed state of the shutter blade based on whether or not the light receiving element receives infrared light. Detection device. 2. The shutter opening / closing detecting device according to claim 1, wherein the infrared light receiving section receives infrared light from the infrared light emitting diode through a shutter opening while the shutter blade is opened. . 3. The infrared light receiving section is directed to the photographic film, and receives the infrared light from the infrared light emitting diode reflected by the photographic film. Shutter open / close detector. 4. The infrared light receiving section is directed to the shutter blade, and directly receives infrared light emitted from the infrared light emitting diode, which is emitted behind the shutter blade. 3. The shutter opening / closing detection device according to 1 or 2. 5. The shutter opening / closing detecting device according to claim 1, wherein the shutter device is a lens shutter incorporated in a photographic lens. 6. The shutter opening / closing detection device according to claim 5, wherein the photographing lens is of a replaceable type that is detachable from a camera body, and the infrared light receiving section is provided on the camera body. .