JPH10133270A - Single lens reflex camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a silver salt camera capable of displaying an electronic image having high quality. SOLUTION: This camera possesses a half mirror 6 arranged at the inside of a photographing optical path, an imaging device 7 receiving the reflected light of the half mirror 6, a main mirror 2 selectively guiding transmitted light through the half mirror 6 to a finder eyepiece part 5 and silver salt film 19, a mirror driving mechanism 24 driving and controlling the main mirror 2 and a control circuit 9 controlling them. The control circuit 9 starts the image pickup operation of the imaging device 7 after the main mirror 2 is retreated to the outside of the photographing optical path and starts the returning operation of the main mirror 2 after the completion of the image pickup operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silver halide camera having a monitor screen for confirming a subject image.

[0002]

2. Description of the Related Art As a device for recording a subject as a still image, a camera using a silver halide film is generally used.
In recent years, with the development of electronic technology, a large number of electronic still cameras, so-called digital cameras, which capture a subject image with a CCD, convert it into digital data and display it on an electronic viewfinder, and store it in a memory element, have been commercialized.
Both have their strengths and weaknesses, and silver halide cameras are superior to digital cameras in terms of the definition of recorded images.However, what kind of photos were taken or the quality of the photos A digital camera is superior in that it is possible to check how much it is at the time of shooting.
Therefore, to compensate for the disadvantages of both, during the exposure operation on the silver halide film, a part of the photographic light beam is guided to the image sensor by a half mirror or the like to capture the subject image data, and after the exposure operation, the subject image is electronically viewed. Various single-lens reflex cameras for displaying on a finder or a monitor screen have been proposed.

[0003]

However, in the single-lens reflex camera as described above, it is necessary to execute the operation of exposing the silver halide film and the operation of capturing an electronic image almost simultaneously. That is, a series of operations such as “mirror up → aperture → shutter drive → aperture opening → mirror down → shutter charge → single frame winding” in silver halide photography and “CCD imaging → analog data reading →
Digital conversion → Storage in memory element → Display on monitor ”
Are performed in parallel.

[0004] However, if the two operations are simply performed in parallel, there is a risk that various inconveniences may occur due to fluctuations in the power supply voltage, motor noise, vibration of the movable member, and the like. In particular, if the mirror is moved up or down during the integration operation of the image sensor, the vibration may cause camera shake,
The motor noise is superimposed and adversely affects the electronic image.

In view of the above problems, the present application provides a camera capable of capturing a high-quality electronic image, and in which a silver halide photographing operation and an electronic image photographing operation cooperate in an optimal state. That is the task.

[0006]

In order to solve the above-mentioned problems, a single-lens reflex camera according to the present invention captures an image of a subject with an image sensor in response to an exposure operation on a silver halide film, and displays the captured data on a monitor screen. In the single-lens reflex camera displayable above, an imaging operation of the imaging device is started after an up operation of the movable mirror, and a down operation of the movable mirror is performed at least after completion of the imaging operation. .

As described above, since the exposure operation of the image pickup device is performed after the movable mirror is raised, it is possible to prevent adverse effects on an electronic image due to vibration and noise.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram of a single-lens reflex camera according to an embodiment of the present invention.

The operation sequence of the camera is controlled by a control circuit 9. The control circuit 9 includes various driving mechanisms (a lens driving mechanism 22, an aperture driving mechanism 14, a mirror driving mechanism 24, a shutter driving mechanism 17, a shutter driving mechanism 17, and a film) that operate in accordance with a control signal output from an output port of the control circuit 9. Feed mechanism 20), various detection mechanisms (lens movement detection mechanism 23, aperture detection mechanism 15, shutter detection mechanism 18, film movement detection mechanism 21) for inputting a state signal to an input port of control circuit 9; A focus detection mechanism 27 for detecting the amount of defocus of the subject; a photometric mechanism 28 for detecting the brightness level of the subject;
A film information setting mechanism 29 for setting the SO sensitivity and the maximum number of photographed frames; and an image processing circuit 8 for processing an electronic image substantially equivalent to an optical image recorded on the silver halide film 19.
Is connected.

Light from a subject passes through a photographing lens 1 and is guided by a main mirror 2 to a focusing screen 3 located above the drawing. The subject image formed on the focusing screen 3 is optically observed from a finder eyepiece 5 via a pentaprism 4. A half mirror 6 for dispersing a part of the photographing light beam is disposed between the photographing lens 1 and the main mirror 2, and about 50% of the subject light beam is reflected by the half mirror 6 obliquely downward and leftward in the drawing. , CCD, or the like. The image sensor 7 converts the subject image on the image plane into analog image data. The image processing circuit 8 generates digital image data by digitally converting (A / D converting) the analog image data from the image sensor 7 in response to a control signal from the control circuit 9 and displays the digital image data on the monitor 10. . Details regarding the image processing circuit 8 and its peripheral circuits will be described later.

A plurality of optical systems 1a constituting the taking lens 1,
An aperture member 13 is disposed between the apertures 1b, and the aperture member 13 is driven by an aperture drive mechanism 14. When the aperture member 13 is driven by the aperture drive mechanism 14, the aperture stop state is detected by the aperture detection mechanism 15,
The control circuit 9 controls the aperture drive in response to a signal from the aperture detection mechanism 15. The aperture detection mechanism 15 detects the movement of a member in the aperture drive mechanism 14 connected to the aperture member 13 by a non-contact type sensor such as a photo interrupter, a photo reflector, and a Hall element.

The shutter 16 is charged and opened and closed by a shutter driving mechanism 17. The charge state and the open / close state of the shutter 16 are detected by the shutter detection mechanism 18, and the control circuit 9 controls the shutter charge and the open / close operation in response to a signal from the shutter detection mechanism 18. Incidentally, the shutter detecting mechanism 18 is also formed of a non-contact type sensor similarly to the aperture detecting mechanism 15.

The silver halide film 19 has a film feeding mechanism 2
0 drives the winding and rewinding. The moving amount is detected by the film moving amount detecting mechanism 21, and the control circuit 9 controls the moving of the silver halide film 19 in response to a signal from the film moving amount detecting mechanism 21. The film moving amount detecting mechanism 21 detects perforations provided on the silver halide film 19 with a photo interrupter, a photo reflector, or the like.

The focus adjusting optical system 1a of the taking lens 1 is driven by a lens driving mechanism 22. Then, the movement amount is detected by the lens movement amount detection mechanism 23, and the control circuit 9 controls the movement of the focus adjustment optical system 1a in response to a signal from the lens movement amount detection mechanism 23. The lens moving amount detecting mechanism 23 detects the amount of rotation of a comb-shaped rotating member provided in a part of the transmission system of the lens driving mechanism 22 with a photo interrupter.

The main mirror 2, which selectively guides the subject light beam to the finder eyepiece 5 and the silver halide film 19, retreats upward (indicated by an arrow U in the figure) prior to the exposure operation. This operation is performed by the mirror driving mechanism 24 including a motor according to a control signal from the control circuit 9.

Further, the control circuit 9 includes the first. Release switch, 2nd. An operation switch group 26 including switches (not shown) related to camera operation, such as a release switch and a back switch, is connected.

Next, the configuration and operation of the image processing circuit 8 will be described in detail. FIG. 2 is a detailed functional block diagram of the image processing circuit 8. 2, an image processing circuit 8 surrounded by a dotted line frame includes a control circuit 81 for controlling a sequence of an image processing operation, an A / D conversion circuit 82 for A / D converting an output of the image sensor 7, and an A / D conversion circuit 82. A digital signal processing circuit 83 for processing the output of the / D conversion circuit 82 to generate image data suitable for monitor display; an image storage circuit 84 for temporarily storing the output of the digital signal processing circuit 83; A readout circuit 85 reads out image data temporarily stored in the storage circuit 84 and displays the image data on the monitor 10.

The control circuit 81 controls two image processing operations, one of which is for taking in analog image data, and the other is for storing and displaying digital image data. is there. The above-described capturing operation causes the image pickup device 7 to start the integration operation in response to the image capturing instruction signal from the control circuit 9, and completes the capturing operation upon receiving the integration end signal from the image capturing device 7. This is an operation of transmitting a signal. The storage and display operation instructs the A / D conversion circuit 82 to A / D convert the output of the image sensor 7 in response to an image storage and display instruction signal from the control circuit 9. Upon receiving the A / D conversion completion signal from the D conversion circuit 82, the digital signal processing circuit 83 is instructed to process image data for monitor display, and when receiving the processing completion signal from the digital signal processing circuit 83, the image storage circuit 84, the output of the digital signal processing circuit 83 is stored.
4 is an instruction to read out the image data stored in the display 4 and display it on the monitor 10, and send a storage and display completion signal to the control circuit 9 upon receiving a display completion signal from the readout circuit 85. .

Next, the operation of the single-lens reflex camera according to the embodiment of the present invention will be described. FIG. 3 is an operation flowchart of the control circuit 9 relating to a main part of the single-lens reflex camera of the present invention. The operation based on this flowchart is based on the power supply S
This processing is executed when W is turned ON or when an idle feeding operation accompanying film loading is performed.

First, in step (hereinafter, referred to as S) 1st. The state of the release switch is checked, and if it is On, the flow proceeds to S2 to execute the <photometry> subroutine. This subroutine is for taking in subject brightness information from the photometric mechanism 28. Next, in a subroutine of <exposure amount calculation> in S3,
An aperture value and a shutter speed value for obtaining proper exposure are calculated from the above-described subject luminance information and the film ISO sensitivity information set by the film information setting mechanism 29.

Subsequently, a subroutine of <focus adjustment> in S4 is executed. This subroutine includes the focus detection mechanism 27
Of the focus adjustment optical system 1 by fetching the focus detection result of
This is the operation of guiding a to the in-focus position.

When these operations have been completed, the process proceeds to step S5 where 2nd. Check the state of the release switch. Here, 2nd. Release switch is Off
f, 1st. in S6. Check the release switch again. At 1st. Release switch is On
If it remains, return to S5 and return to 2nd. Repeat the check of the release switch. If the release switch is off, the process returns to S1 again.

On the other hand, at S5, 2nd. If it is determined that the release switch is ON, the process proceeds to S7, where a <aperture closed> subroutine is executed. In this subroutine, the aperture member 13 is driven by the aperture drive mechanism 14 to the aperture value obtained in the <exposure amount calculation> subroutine.

Thereafter, the mirror driving mechanism 24 is driven in the <main mirror up> subroutine of S8 to perform the operation of raising the main mirror 2. Then, when the main mirror 2 is raised, the shutter driving mechanism 17 is driven to open the shutter 16 in S9, and then an image capture instruction signal is transmitted to the image processing circuit 8 in S10. Note that the image processing circuit 8 executes the above-described operation of capturing the analog image data in response to this signal, but the control circuit 9 proceeds to S11 without waiting for the capture completion signal from the image processing circuit 8. Wait until the exposure time calculated in the <exposure amount calculation> subroutine elapses.
At 12, the operation of returning the shutter 16 to the closed state is preferentially executed. Therefore, even if a capture completion signal is transmitted from the image processing circuit 8 during that time, the control circuit 9 does not respond to it.

After performing the shutter closing operation in S12,
In S13, it is checked whether or not there is a capture completion signal from the image processing circuit 8. Generally, the integration of the image sensor 7 is completed during the time counting operation and the shutter closing operation at the exposure time, so this check is often meaningless. However, depending on the combination of the film ISO sensitivity and the aperture value, It is conceivable that the timing of the exposure time may end before the integration operation ends, and if the mirror-down operation starts at this time, the electronic image is transferred to the main mirror 2 or the mirror driving mechanism 24.
There is a risk of blurring due to vibration or noise from Therefore, in order to prevent the operation from proceeding to the next mirror-down operation unless the integration operation of the image sensor 7 is completely completed, the capture completion signal is checked in S13.

After confirming the capture completion signal, an image storage and display instruction signal is transmitted to the image processing circuit 8 in S14. Subsequently, in S15, a subroutine for a down operation of the main mirror 2 is executed, and then, in a subroutine of <aperture opening> in S16, the aperture member 13 is returned to the open state. Then, in step S17, the <one frame winding up> subroutine is executed. In this subroutine, the film feeding mechanism 20 winds the silver halide film 19 by one frame.

The image processing circuit 8 responds to the image storage and display instruction signal transmitted in S14 described above in S15.
While the operations from S17 to S17 are being performed, A / D conversion, storage, and display operations of the captured image are performed, and when these operations are completed, a signal to complete the storage and display of the image is transmitted to the control circuit 9. The control circuit 9 determines whether or not this signal has been transmitted at the time when the subroutine <one frame winding> has been completed.
Check at 8. This check is substantially unnecessary as in the case of the above-described check of the fetch completion signal. However, if this check is performed, no abnormality occurs in the sequence even if the timings of the two are reversed for some reason.

After confirming the completion signal of image storage and display in S18, the process proceeds to S19. Here, the maximum number of photographed frames set by the film information setting mechanism 29 is compared with the number of exposed frames, and if they match, it is determined that the last photographed frame has been photographed, and the process proceeds to <rewind>. If not, the process returns to S1.

As described above, in the single-lens reflex camera according to this embodiment, the integration operation of the image pickup device 7 is performed between the main mirror up and the main mirror down. The electronic image does not become unclear, and noise is not superimposed on the image data due to noise during powering of the motor or fluctuation in power supply.

If the A / D conversion operation is also susceptible to motor noise, the A / D conversion operation may be performed together with the CCD integration operation between the mirror up and down.

Further, by further comprising an interface means for externally outputting the image data processed by the image processing circuit 8, secondary use such as correction and display by an information processing device such as a personal computer is possible.

Further, the present invention embodied by the above-described embodiments can be variously modified without departing from the gist of the present invention. As described above, the present invention has been described based on the embodiments, but the present invention includes the following inventions. That is, (1) in a single-lens reflex camera having a movable mirror that retreats outside the photographing optical path before the exposure operation on the film and returns after the exposure operation, is disposed in the photographing optical path and reflects a part of the photographing light beam A half mirror, a mirror driving unit that drives the half mirror, an image sensor that receives a light beam reflected by the half mirror, and captures a subject image, and an image processing unit that generates a digital image from the output of the image sensor. Display means for displaying the digital image,
Control means for performing an image pickup operation of the image pickup device after the retracting operation of the movable mirror, and performing control so that a return operation of the movable mirror is executed after the end of the image pickup operation. Reflex camera. (2) The camera of (1) is controlled so that the integration operation of the image pickup device is executed after the retracting operation of the movable mirror, and the return operation of the movable mirror is executed after determining the end of the integrating operation. Control means for performing the operation. (3) a movable mirror that retracts outside the photographing optical path before the exposure operation and returns after the exposure operation, film winding means that winds up the film after the exposure operation, and a film winding means that is disposed in the photographing optical path and A half mirror that partially reflects, an imaging element that receives a light beam reflected by the half mirror and captures a subject image, an image processing unit that generates a digital image from the output of the imaging element, and displays the digital image. A single lens reflex camera, comprising: a monitor means for performing an image capturing operation of the image sensor after the retracting operation of the movable mirror, and returning the movable mirror after the image capturing operation is completed. Starting the operation of the movable mirror from the start of the returning operation of the movable mirror to the completion of the winding operation by the film winding unit; A single-lens reflex camera characterized by performing the above operations in parallel.

According to such a camera, the operation of the image processing means is executed in parallel from the start of the return operation of the movable mirror to the completion of the winding operation by the film winding means. , A continuous shooting operation can be performed at high speed. (4) In a single-lens reflex camera capable of capturing an image of a subject with an image sensor in synchronization with an exposure operation on a silver halide film and displaying the captured data on a monitor screen, a source of vibration or noise, and A spectroscopic means for dispersing a part of the photographing light beam, an image sensor for receiving the light beam dispersed by the spectroscopic means to capture a subject image, and an image processing means for generating a digital image from the image sensor output A single-lens reflex camera, comprising: display means for displaying the digital image; and control means for prohibiting an imaging operation of the imaging element during operation of the vibration or noise source. .

According to such a camera, the image pickup operation of the image pickup device is inhibited during the operation of the source of the vibration or noise, so that the electronic image becomes unclear or noise is superimposed on the image data. There is no.

[0035]

According to the present invention, with respect to a camera having a monitor screen for confirming a subject image, a high-quality electronic image can be captured, and a silver halide photographing operation and an electronic image photographing operation can be performed. A single-lens reflex camera that cooperates in an optimal state can be provided.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a single-lens reflex camera according to an embodiment.

FIG. 2 is a detailed functional block diagram of an image processing circuit 8 of the camera.

FIG. 3 is an operation flowchart of a control circuit 9 of the camera.

[Explanation of symbols]

 Reference Signs List 1 shooting lens 2 main mirror 5 viewfinder eyepiece 6 half mirror 7 image pickup device 8 image processing circuit 9 control circuit 10 monitor 19 silver halide film 24 mirror driving mechanism

Claims (3)

[Claims] 1. A single-lens reflex camera capable of capturing an image of a subject with an image sensor in accordance with an exposure operation on a silver halide film and displaying the image data on a monitor screen. A single-lens reflex camera, wherein an imaging operation is started, and a down operation of the movable mirror is performed at least after the imaging operation is completed. 2. A single-lens reflex camera having a movable mirror that retreats outside a photographing optical path before an exposure operation on a film and returns after an exposure operation, is disposed in the photographing optical path and reflects a part of a photographing light beam. A half mirror, an image sensor that captures a subject image by receiving the light beam reflected by the half mirror, an image processing unit that generates a digital image from the output of the image sensor, and a display unit that displays the digital image And control means for performing an image pickup operation of the image pickup device after the retracting operation of the movable mirror, and controlling to execute a return operation of the movable mirror after the image pickup operation is completed. SLR camera to do. 3. A first control means for performing an image pickup operation of the image pickup device after the retracting operation of the movable mirror, and performing control such that a return operation of the movable mirror is executed after the image pickup operation is completed; The single-lens reflex camera according to claim 2, further comprising: a second control unit configured to execute the operation of the image processing unit in parallel with the return operation of the movable mirror.