JP2001066692A - Electronic control system for single lens reflex camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use AE and AF functions at mirror-up photographing similar to those at normal photographing. SOLUTION: The electronic control system is provided with a mirror position detecting switch 40 at a mirror-up start position, and in a state where a starter switch is turned on, locking and storing operations of photometry values and range finder values are executed when a release switch is turned on at normal photographing, while at mirror-up photographing, the locking and storing operations are executed when the off signal of the mirror position detecting switch 40 is detected by a CPU. Thus, by executing a mirror-up operation by operating a mirror-up knob 35 and then turning the release switch on, the mirror-up photographing with the AE and AF functions enabled is accomplished. Even in the case of changing the composition and illumination in the middle of mirror-up photographing, the photometry values and the range finder values are renewed by executing a mirror-down operation by operating the mirror-up knob 35, and by executing the mirror-up operating again thereafter, the photographing effect corresponding to the new composition and illumination is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control means for electronically controlling photometry and / or distance measurement using a light beam passing through a photographing lens, and a mirror-up mechanism for raising a mirror independently of a shutter release to prevent blur due to vibration. And an electronic control system for a single-lens reflex camera.

[0002]

2. Description of the Related Art Generally, a mirror operation of a single-lens reflex camera of this type has a structure in which the ascending process is performed mechanically and a shutter operation is started at a final stage of the ascending of the mirror. In this method, the mirror frame is directly driven from the outside to stop at the raised position, and the shutter is separately released.

The automatic exposure (hereinafter, referred to as "AE") and the automatic focus (hereinafter, referred to as "AF") of a conventional electronic single-lens reflex camera measure light rays passing through a photographic lens (not shown) and reflected by a mirror or a sub-mirror, respectively. The calculation result is stored immediately before exposure, and electronic control is performed by a central control unit (hereinafter, referred to as "CPU") based on the stored content.

However, after the mirror-up operation in the mirror-up photographing, as shown in FIG. 6, a normal measurement light beam does not enter each of them, so that the photometric value becomes low level.
Since the distance measurement value is a state in which a non-imaging surface which is completely different from the film surface is measured, it is generally designated to perform photographing by manual setting.

[0005]

However, in such a conventional electronic control system of a single-lens reflex camera, the electronically controlled AE, A
Needless to say, if the F control function can be used, it is desirable. Among them, the AE control has realized the direct photometry system using the reflection of the film surface or the curtain surface of the focal plane shutter regardless of the mirror. However, unlike the AE control, the operation is completed before the exposure, unlike the AE control. Must be performed and cannot be performed inseparably from the mirror operation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to make it possible to use the AE and AF control functions even when the mirror of a single-lens reflex camera having at least one of the AE and AF functions is raised. And

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a control means for electronically controlling photometry and / or distance measurement using a light beam passing through a photographing lens, and raising a mirror independently of a shutter release. An electronic control system for a single-lens reflex camera having a mirror-up means for turning on and off the mirror position detection means.
An object of the present invention is to provide an electronic control system of a single-lens reflex camera that switches to one of an update mode and a memory lock mode when turned off. In the electronic control system for the single-lens reflex camera, the mirror position detecting means may be a switch linked to the mirror holder or a switch linked to the mirror-up operating member.

The electronic control system for a single-lens reflex camera according to the present invention is constructed as described above, so that even when the mirror is up, which is not related to the shutter release, the measured value before the mirror is raised is stored and the actual shutter release is performed. Automatic control can be performed, and the operability of the single-lens reflex camera having the mirror-up means can be greatly improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a basic configuration for implementing the present invention in a control system of a single-lens reflex camera will be specifically described with reference to the drawings. FIG. 1 is an explanatory diagram showing a state when a mirror descends in one embodiment of the present invention, and FIG. 2 is an explanatory diagram showing a state when a mirror rises.

First, referring to FIG. 1, a pair of left and right pivots 2, 2 and 3 are provided on an inner wall of a mirror box 1 indicated by a virtual line.
A mirror frame 7 to which a mirror 6 is fixed is pivotally supported on shafts 8, 8 and 9, 9 to a first mirror arm 4 and a second mirror arm 5 which are rotatably supported by 3. In FIG. 1, each of the pair of left and right members shows only one member on the left side.

A spring 12 is provided between a pin 10 implanted in one arm of the first mirror arm 4 which projects through the through hole 1a of the mirror box 1 and a spring hook 11 implanted in the mirror box 1. And the spring 12 causes the mirror frame 7 to be engaged.
Is biased clockwise in the figure, and is positioned by positioning pins 13 implanted on the inner wall of the mirror box 1.

A distance measuring member 14 is fixed to the bottom of the mirror box 1, and a part of the photographing light beam passes through a semi-light transmitting portion near the center of the mirror 6 and a through hole 7 a of the mirror frame 7. A distance measuring member 14 which is urged in the left-hand direction in the figure by a spring (not shown) on the back side and reflected by a sub-mirror 17 fixed to a sub-mirror frame 16 which is rotatably pivoted, and which is equidistant from the film surface 15 with respect to the sub-mirror 17 To measure the distance. The sub-mirror frame 16 is positioned when the mirror frame 7 is lowered by a pin 16a implanted on the side surface and a cam 18 fixed to the mirror box 1, and when the mirror is raised as shown in FIG.
Is rotated to a position for blocking the through hole 7a.

On the other hand, a photometric member 19 is mounted in a finder (not shown), and an image of a screen 20 reflected and guided by the mirror 6 when the mirror frame 7 is lowered is displayed on the finder optical system 2.
Partial or average photometry is performed through 1.

A mirror-up knob 35 operable from outside is mounted on the left side surface of the mirror box 1 so as to be rotatable by a predetermined angle, and a mirror-up lever 36 is fixedly provided coaxially with the mirror-up knob 35. The drive unit 36a
Can be brought into contact with the pin 10 implanted in the first mirror arm 4. When the mirror-up knob 35 is rotated in the counterclockwise direction in FIG. 1, the driving unit 36a of the mirror-up lever 36 integrated with the knob presses the pin 10, and the first and second mirror arms 4, 5 Turns clockwise against the urging force of the spring 12 so that the mirror frame 7 can be turned to the raised position.

A pin 37 is planted on the mirror up lever 36, and a spring 39 is engaged between the pin 37 and a spring hook 38 planted on the left side of the mirror box 1, and a mirror up knob 35 is provided. Is reciprocated, the spring 39
Are applied in two directions to stop the click at both ends.

A mirror position detecting switch 40 constituting a mirror position detecting means is provided on one of the inner wall surfaces (preferably the left inner side surface) of the mirror box 1, and FIG.
As shown in the figure, when the mirror frame 7 is lowered,
The movable contact piece is pressed by the fixed contact piece by b, so that the movable contact piece is in an on state, and is turned off when the mirror frame 7 starts to ascend (see FIG. 2).

FIG. 3 is a block diagram showing a control system for a single-lens reflex camera having the above configuration. CP
The U30 is shown in FIGS. 1 and 2 together with the shutter speed, aperture, film sensitivity, and other set values 32 that are input when the start switch 31 is turned on by half-pressing a release button (not shown) or pressing a release lock switch. The photometric value 33 by the photometric member 19 and the distance value 34 by the distance measuring member 14
Is stored in the memory and updated at predetermined pulse intervals.

The CPU 30 includes a start switch 31 and a mirror position detection switch 40 as well as a release switch 42 by pressing a release button (not shown).
A shutter release switch 44 that is turned on at the end of the rising of the mirror frame 7 is input, controls the AF control mechanism 43, the shutter mechanism 45, and the aperture mechanism 46, and displays the respective control results by turning on the start switch 31.
1 is displayed.

Next, the operation of the mirror-up device having the above configuration will be described. The mirror up operation
As shown in FIG. 2, when the mirror-up knob 35, which is the operation member, is turned counterclockwise in FIG. 2, the driving unit 36 a of the mirror-up lever 36 integral with the knob comes into contact with the pin 10 implanted in the first mirror arm 4. First and second mirror arms 4,
5 rotates clockwise against the urging force of the spring 12 to rotate the mirror frame 7 to the raised position.

The mirror position detection switch 40 is pressed by the tip 7b at the lowered position of the mirror frame 7 and is turned off when the mirror frame 7 starts to be raised in the on state. As shown in FIG. 4, the CPU 30 locks the photometry value 33 and the distance measurement value 34 with the off signal and stores them in the memory.

When the mirror-up knob 35 is click-stopped to the right-handed mirror position by the biasing force of the spring 39, the first mirror arm 4 is rotated leftward by the biasing force of the spring 12, and the mirror frame 7 is lowered. Pivot to the position. The mirror position detection switch 40 is turned on when the mirror frame 7 is lowered, and the photometry and the distance measurement are restarted as shown in FIG. 4, and the photometry value 33 and the distance measurement value 34 are repeatedly updated at predetermined pulse intervals.

With such an operation and the configuration shown in FIG.
When the start switch 31 is turned on, the PU 30 starts photometry, distance measurement, and the operation of the display unit 41, and then locks with the release signal of the release switch 42 in normal shooting and the off signal of the mirror position detection switch 40 in mirror-up shooting. The AF control mechanism 43 is controlled by the distance measurement value 34, and the shutter mechanism 45 and the aperture mechanism 46 are controlled by a shutter release switch 44 that is turned on at the end of operation of a mirror driving member (not shown).

In the above-described embodiment, the mirror position detection switch 40 is turned on when the mirror is lowered and detects an off signal at the start of rising. The signal may be detected.

As another embodiment of the present invention, as shown in FIG. 5, a distal end portion 36b of a mirror up lever 36 coaxially integrated with a mirror up knob 35 presses a mirror position detection switch 40 at a mirror lowered position. It is also possible to turn on the mirror and turn off the mirror up knob 35 at the same time as starting to turn left.

According to this embodiment, the driving portion 36a of the mirror up lever 36 is connected to the pin 1 of the first mirror arm 4.
The mirror position detection switch 40 is turned off before the mirror frame 7 is raised by contacting the
Since 4 is stored in the memory of the CPU 30, more accurate control becomes possible. At the same time, when the mirror frame 7 is lowered, no force in the twisting direction is exerted by the mirror position detection switch 40. Therefore, especially when used in a medium-format single-lens reflex camera, the flatness of the mirror 6 is secured and a good finder image is obtained. Can be.

In any of the embodiments, the start switch 31 is turned on when the release button is half-pressed, so that during the mirror-up shooting, the on-state is maintained for a predetermined time even when the release button is stopped. By doing so, the operability can be further improved.

[0027]

As described above, the electronic control system for a single-lens reflex camera according to the present invention makes it possible to use the AE and AF functions that are effective in normal photographing even during mirror-up photographing, and to perform manual setting. This eliminates the need to perform shooting and reduces shooting errors. Further, even when the composition or illumination is changed during the mirror-up shooting, the photometry value and the distance measurement value are updated by operating the mirror-up knob one reciprocation, so that the operability is improved.

In the above electronic control system for a single-lens reflex camera, if the mirror position detecting means is a switch linked to the mirror holder, the desired effect can be obtained with a very simple configuration. If the switch is linked to the up operation member, the measured value can be stored in memory and locked before the mirror starts to move up, so that more accurate control is possible and the flatness of the mirror is secured. As a result, a good finder image can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a state when a mirror descends in one embodiment of the present invention.

FIG. 2 is an explanatory view showing a state in which the mirror rises.

FIG. 3 is a block diagram showing a configuration of a control system according to the present invention.

FIG. 4 is a timing chart showing the relationship between a mirror detection switch and photometry and distance measurement values.

FIG. 5 is a partial explanatory view showing another embodiment of the present invention.

FIG. 6 is a timing chart similar to FIG. 4, showing a control system for a conventional single-lens reflex camera.

[Explanation of symbols]

 1: Mirror box 1a: Through hole 2, 3: Axis 4: First mirror arm 5: Second mirror arm 6: Mirror 7: Mirror frame 7a: Through hole 8, 9: Axis 10: Pin 11: Spring hook 12: Spring 13: Positioning pin 14: Distance measuring member 15: Film surface 16: Submirror frame 16a: Pin 17: Submirror 18: Cam 19: Photometric member 20: Screen 21: Viewfinder optical system 30: CPU 31: Start switch 32: Set value 33: Photometry value 34: Distance measurement value 35: Mirror up knob 36: Mirror up lever 36a: Driving unit 36b: Tip 37: Pin 38: Spring hook 39: Spring 40: Mirror position detection switch 41: Display Section 42: release switch 43: AF control mechanism 44: shutter release switch 45: shutter mechanism 46: aperture mechanism

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H002 CC41 DB07 DB08 GA35 JA02 2H011 AA01 BA21 CA21 DA00 2H051 AA06 BA01 EA06 EA27 GB12 GB20 2H054 CB18

Claims (3)

[Claims] 1. An electronic control system for a single-lens reflex camera having a control means for electronically controlling photometry and / or distance measurement using a light beam passing through a taking lens and a mirror-up means for raising a mirror independently of a shutter release. An electronic control system for a single-lens reflex camera, wherein the control means switches between an update mode and a memory lock mode by turning on and off the mirror position detection means. 2. An electronic control system for a single-lens reflex camera according to claim 1, wherein said mirror position detecting means is a switch linked to a mirror holder. 3. An electronic control system for a single-lens reflex camera according to claim 1, wherein said mirror position detecting means is a switch linked to a mirror-up operating member.