JP3063778B2 - camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to a motor-driven photographing screen switching camera in a variable magnification camera.

[0002]

2. Description of the Related Art In recent years, the functions of cameras have been diversified, and one of them is switching of photographing screens. The switching of the shooting screen relates to, for example, switching to a half size or a panorama size with respect to the full size. In the camera, it is necessary to switch the field of view of the finder in conjunction with the switching of the shooting screen. For example, a view frame Fn shown in FIG. 19A is a viewfinder view frame during normal shooting, and a view frame Fp1 shown in FIG. 19B during a panorama shooting of a conventional camera. . Many proposals have been made for these switching mechanisms.

[0003] For example, a photographing area sorting device in a camera disclosed in Japanese Utility Model Publication No. 35-25058 is a full-size / half-size switching mechanism, which switches a real screen mask in conjunction with manual operation. It is.

[0004]

However, in the apparatus disclosed in JP-B-35-25058, the size cannot be changed by one-touch operation because the size is changed by a manual operation. In the case where the required operation amount is large, a space for a large operation member must be provided in the external part of the camera body, which causes a problem such as a restriction in design.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem, and a camera uses a motor serving as a drive source of a variable-power driving mechanism, and a screen switching mechanism via the variable-power driving mechanism. By changing the magnification of the view frame switching mechanism and the finder optical system, the user can switch the screen with one touch operation, switch the finder visual field, and also switch the magnification of the finder optical system at the same time, making it easier to use and design. Is a constraint on
It is an object of the present invention to provide an easy-to-use camera which can be applied to a smaller number of cameras, and can be applied to a recent bifocal camera or a zoom camera, and can simultaneously switch not only a finder field frame but also a finder magnification.

[0006]

The camera of the present invention SUMMARY OF THE INVENTION comprises a variable power drive mechanism for zooming drives the photographing optical system, a motor serving as a drive source of the variable power drive mechanism, the shooting screen size A finder optical system having a zoom ratio greater than that of the photographing optical system, and a field frame switching mechanism for changing the size of a finder field frame provided in the finder optical system. doing.

[0007]

The screen switching mechanism and the field frame switching mechanism are operated by a variable power drive mechanism using the motor as a drive source, and the magnification of the finder optical system is changed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. Prior to the description of the embodiments, the outline of the variable magnification photographing optical system, the finder optical system, the photographing screen switching mechanism, and the finder field frame switching mechanism of the camera of the present invention will be described.

FIG. 1 is an exploded perspective view of the camera.
This camera comprises a camera body 4, a lens barrel, a finder unit, a zoom motor unit 10, and a photographing screen switching mechanism. Note that switching of the shooting screen includes normal shooting (hereinafter referred to as N shooting).
Normal size in mode (so-called full size 24mm x
From a screen of 36 mm (hereinafter referred to as N size) to a half size screen at the time of half size photographing or a panoramic size (13 mm × 36 mm, hereinafter referred to as P size) in a panoramic photographing (hereinafter referred to as P photographing) mode Although there is a switch to the screen, in the case of the present camera, the description will be made assuming that the screen is switched from a full size screen at the time of N shooting to a panoramic size screen at the time of P shooting.

The zoom motor unit 10 is supported by the main body 4 and includes a zoom motor 10a and a gear train 10b, and drives the cam ring 6.

The lens barrel comprises a fixed frame 5, a cam ring 6 rotatably supported by the fixed frame 5 and constituting a variable magnification drive mechanism of the photographing optical system, a photographing lens (not shown), , An encoder for detecting the rotational phase of the cam ring 6. On the outer periphery of the cam ring 6,
A finder cam 7 having a second area is guided by the pins 6a and 6b and is rotatably arranged in the circumferential direction. Also,
A gear 9 meshing with the gear train 10b is fixed to the cam ring 6. Further, abutment surfaces 6c and 6d for operating a P-ring 3, which will be described later, are provided at the outer peripheral end of the cam ring 6. Note that the finder cam 7 is
It is held at two relative positions corresponding to the N shooting mode and the P shooting mode via a relative position holding mechanism described later. The switching of the relative position is performed by shifting the holding position by applying the end faces 7d and 7e of the cam 7 to the stoppers 4i and 4k of the main body 4. On the outer periphery of the cam ring 6, a flexible substrate 25 of an encoder pattern with which the contact piece 26 slides is provided.

The finder unit includes a finder body 8.
And a guide shaft 29 supported by the main body 8 and an F frame 11, 1 for a finder lens slidably supported by the shaft 29.
2, finder zoom lenses 11b and 12b held by the frames 11 and 12, a switching lever 13 for operating a field mask constituting a field frame switching mechanism, and an F frame suspended from the frames 11 and 12 with each other. It comprises a spring 14, a porro prism (not shown), a field mask, an eyepiece, and the like. The finder body 8 is attached to the camera body 4.

The photographing screen switching mechanism is disposed in front of the standard mask opening 4d of the camera body 4, and includes movable masks A1 and B2 for switching photographing screens and a P-ring for operating the mask. And 3. The guide pins 1b and 2b of the mask A1 and the mask B2 can be moved to respective screen switching positions by being guided by the straight guide grooves 4i of the main body 4.

When the photographing screen is switched, the P ring 3 is rotated to a predetermined position by pressing the operation arm 3f by the contact surfaces 6c and 6d of the cam ring 6 using the zoom motor 10a as a driving source. Then, by the rotation, the mask A fitted to the notch grooves 3a, 3b provided on the inner periphery thereof
1 through the drive pins 1a and 2a of the mask B2. B is moved to a position giving each screen size.

The operation of the above-configured camera will be described. First, in the zoom operation of the camera, the cam ring 6 is rotated by the zoom motor 10a based on the zoom control signal, and the zooming operation is performed. . Also,
Based on the zoom operation, F frame 1 of the finder unit
The cameras 1 and 12 are driven in the axial direction by a finder cam 7 to perform zooming of a finder image.

The photographing screen is switched by rotating the P-ring 3 via the cam ring 6 by the zoom motor 10a.
By rotating the ring 3 in a counterclockwise direction (hereinafter referred to as CCW), the masks A1 and B2 are opened up and down to form an imaging portion opening corresponding to the N size. When the P photographing mode is switched, the P ring 3 is rotated clockwise (hereinafter, referred to as CW) to move the masks A1 and B2 so as to approach each other to form an image forming portion opening corresponding to the P size. In conjunction with the switching operation, the driving arm 3g presses the operation arm 13a of the switching lever 13 of the field mask of the finder unit and operates the finder field frame switching mechanism to set the finder field frame corresponding to the photographing screen size. give.

Further, the relative positions of the cam ring 6 and the finder cam 6 are also switched in accordance with the switching of the photographing screen. That is, when the cam ring 6 is rotated in the CCW and CW directions, the finder cam 7 contacts the stoppers 4i and 4k,
When further rotated, the relative position between the cam ring 6 and the finder cam 7 changes. Therefore, F frame 1 of the finder unit
The areas where the 1.12 cam pins 11a and 12a are in sliding contact with the cam surfaces 7a and 7b of the finder cam 7 differ according to screen switching. And the area is N
The first area is used for shooting, and the second area is used for P shooting. However, the first and second regions are formed continuously on the cam surfaces 7a and 7b.

As described above, in the present camera, the finder field frame size is switched in accordance with the switching of the photographing screen size between N photographing and P photographing, and at the same time, the value of the magnification of the finder is changed. To prevent the viewfinder from being hard to see. For example, as shown in FIG. 19, the finder field frame at the time of P photographing is Fp2 instead of the field frame Fp1 as in the conventional example.

FIGS. 2 and 3 show the zooming operation of the photographing lens and the finder variable magnification lens. As shown in FIG. 2, the extended positions of the first group lens 18a and the second group lens 19a, which are photographing lenses, in the wide state (A) and the tele state (B) are shown. And
The respective focal lengths f are 28 mm and 56 mm, and the magnification is 2.

On the other hand, FIG. 3 shows a finder optical system, and shows the positions of the variable magnification lenses 11b and 12b of the finder in the wide state (A) and the tele state (B). And
The range of the magnification is 0.35 to 0.91. Therefore, the total magnification ratio becomes 2.6. However, the range of use of the scaling factor is limited according to the screen switching. The range of zooming corresponding to the first area of the finder cam for N shooting is 0.35 to 0.7, and the range of zooming corresponding to the second area for P shooting is 0.455 to 0.91. And
Therefore, as shown in FIG. 19, the field frame Fp2 at the time of P photographing is also enlarged in the width direction.

Next, the main structure of the lens barrel will be described with reference to FIG. This lens barrel has an advance distance of 28 mm
A zoom lens barrel having a length of from 56 mm to 2 mm, and a first lens group holding a first lens group 18a slidably fitted into the fixed frame 5 as shown in FIG.
It is composed of a group frame 18 and a moving frame 20 that supports the second group frame 18 of the second group lens 19a. And the frame 1
The movement of 8, 19 in the direction of the front axis O is performed by driving the cam pins 21, 22 fixed to the frame 18 and the moving frame 20 by the cams 6c, 6d of the rotating cam ring 6. The cam pins 21 and 22 are guided in the optical axis O direction by the rectilinear grooves 5a and 5b of the fixed frame 5.

The shutter blades 24 are operated by a shutter focusing mechanism 23 provided inside the moving frame 20. At the same time, focusing drive of the first group lens 18 is performed via the drive pins 18b of the first group frame 18.

Next, the configuration of the optical system of the finder unit will be described with reference to FIG. This finder unit mainly includes a finder optical system lens, a Porro prism 15, a field mask 16 and a switching lever 13 which are a field frame switching mechanism.

As shown in FIG. 5, a Porro prism 15 having four reflecting surfaces is separated into two right and left bodies, and an image forming surface of a finder image forming system is positioned between them. The field mask 16 of the finder is composed of two sheets, and the long hole 16a is engaged with the projection 15a of the Porro prism 15, and is held slidably. The field switching lever 13 is connected to the viewfinder body 8.
1 (FIG. 1), and is urged in the CCW direction by a field spring 17. When the P ring 3 shown in FIG. 1 is rotated in the CW direction by the P imaging switching operation,
The arm 3g of the P ring 3 is the arm 13a of the visual field switching lever 13.
To rotate the field switching lever 13 in the CW direction against the field spring 17. At this time, the field frame switching lever 13
The U-shaped groove 13b is engaged with the projection 16b of the field mask 16, so that the field mask 16 moves in the longitudinal direction of the long hole 16a, and the field frame size is switched.

The camera of the present invention has a schematic configuration as described above. Next, a camera according to a first embodiment of the present invention will be described in detail with reference to FIGS. The structure of the camera of this embodiment is the same as that of the camera shown in FIG. 1 except for the shape of the P-ring of the screen size switching mechanism. FIG. 6 is a front view of the state of the screen switching mechanism in the N shooting mode as viewed from the subject side. And FIG.
FIG. 7 is a sectional view taken along line AA of FIG. FIG. 8 shows that P
FIG. 9 is a sectional view taken along the line BB of FIG.

The above-described screen switching mechanism is disposed between the surface 4f of the mask 4d of the camera body 4 and the end face 5a of the fixed frame 5. The switching mechanism includes a mask A1, a mask B2 for determining an actual photographing screen size in P photographing, a P ring 33 for switching a mask position, an opening 4d of the main body 4 for giving an N size of the actual screen in N photographing, It consists of. The axial direction of the P-ring 33, the mask A1, and the mask B2 is regulated by the end surface 5a of the fixed frame 5 and the P-ring receiving surface 4e of the main body 4. Then, the P ring 33 is rotatably held by the outer peripheral receiving portion 4a. The rotation of the P-ring 33 is performed by pressing the operating arm 33f by the contact portion 6c or 6d of the cam ring 6.

The mask A1 and the mask B2 have pins 1b and 2b for guiding at the time of movement, and are fitted in the straight guide grooves 4c. The driving pins 1 a and 2 a provided on those masks are fitted in the cutout grooves 33 a and 33 b of the P-ring 33. Further, the P ring 33 is in contact with 33e, 33
d, and the stopper 4b of the main body 4 comes into contact with the contact surface, and the N imaging position and the P imaging position are determined. And P
The click projection 33c of the ring 33 fits into the click groove 4g or 4h of the main body 4 and is positioned with a click holding force.

Next, the operation of the screen switching mechanism will be described. In the N photographing mode state of FIG. 6, the mask A1 and the mask B2 are separated from each other and are located outside the range of the mask opening 4d of the main body 4, so that the opening 4
The N size (full size) of the actual screen is determined by d. In this state, the contact surface 33d of the P-ring is in contact with the stopper 4b, and the click protrusion 33c is fitted in the click groove 4g. From this position, the cam ring 6
Abuts the contact portion 6d on the operating arm 33f to connect the P-ring to C
When rotated in the W direction, the notch groove 33 of the P ring 33
The pins 1a and 2a of the masks A1 and B2 are driven by a and 33b, and the masks A1 and B2 move downward or upward along the guide grooves 4c of the main body 4. When further rotated, the contact surface 33e comes into contact with the stopper 4b, the P ring 33 is positioned at the P photographing mode position shown in FIG. 8, and the click protrusion 33c fits into the click groove. In this state, the masks A1 and B2 are close to each other, and form an area of a real screen size of P size (panorama size) by the respective end faces 1d and 2d.

To return to the N photographing mode again,
The operation arm 33f of the P-ring 33 can be pressed and rotated in the CCW direction by the contact portion 6c of the cam ring 6 to return to the state of FIG. In this embodiment, the P ring 3
The shape of the opening 33h at the center of 3 has a required minimum dimension not smaller than the opening 4d of the main body, and is configured to block unnecessary light as much as possible.

Next, a description will be given of a zoom mechanism of the finder optical system which is linked to the zooming and screen switching operations of the camera according to the present embodiment. 10 and 11 show a longitudinal sectional view of the finder cam 7 and the cam ring 6 in a wide state in the N photographing mode, and a development view thereof. FIG.
Reference numeral 13 denotes a longitudinal sectional view in a telephoto state in a P photographing mode, and a developed view thereof. Rotable finder cam 7
Are held at one of two positions on the outer periphery of the cam ring 6 via a relative position holding mechanism described later. The rotation range θ of the zooming of the cam ring 6 under the holding state
The finder cam 7 and the cam ring 6 rotate integrally. In FIGS. 10 and 12, the rotation angle θ of the cam ring 6 is an angle shown in a range from the wide position θA indicated by the guide pin 6a to the tele position θB.

Then, as shown in FIGS.
In the photographing mode, the cam pins 11a of the F frame 11 and the cam pins 12a of the F frame 12
Due to the urging force of the finder cam 7 (see FIG. 1), the finder cam 7 is in contact with the cam surfaces 7a and 7b. The pin positions 11a (W / N) and 12a (W / N) indicate the pin positions in the wide state at the time of N photographing. Then, when the cam ring 6 rotates to the telephoto position by the zoom operation, the F frame 11, 1
The second cam pins 11a and 12a slide while contacting the cam surfaces 7a and 7b of the finder cam 7, and the pin position 11a
(T / N) and 12a (T / N). Pin 11
a, 12a The range from the (W / N) position to the (T / N) position is the first region RN of the finder cam 7 used during N photographing, and the finder magnification is 0.35 to 0.
7 times.

In order to switch from the N photographing mode in FIG. 10 to the P photographing mode in FIG. 12, the cam ring 6 in FIG. 10 is moved beyond the wide end to the P rotational position θC (pin 6a position). Rotate by angle θP. At this time,
The end face 7e of the finder cam is the stopper 4h of the camera body.
And the finder cam 7 is further pressed, so that the finder cam 7 is rotated about the angle 6P with respect to the pin 6a against the holding force of the position holding mechanism, and positioned at the relative position in the P photographing mode state. . However, this state is a wide state.

FIGS. 12 and 13 show the telephoto state of the P photographing. When the cam ring 6 rotates to the wide side from this state, the cam pins of the F frames 1 and 2 become 11a (T / P) and 12a.
From the (T / P) position, 11a (W / P) and 12a (W / P)
It moves to the position P) while abutting on the cam surfaces 7a and 7b. This range is the second region Rp of the finder cam 7 used for P photographing. 0.45 as finder magnification
It becomes 5 times to 0.91 times. 11 and 13, the second area Rp of the finder cam 7 is equal to the first area Rp.
It is formed in a shape that extends N.

In order to return to the N photographing state again, FIG.
As shown in FIG. 2, the cam ring 6 is rotated beyond the telephoto end by the N photographing switching angle θN, that is, to the rotation position θD with respect to the position of the pin 6a. With this operation, the end face 7d of the finder cam 7 comes into contact with the stopper 4i of the main body, and the finder cam 7 is further rotated in the CW direction relative to the cam ring 6 so as to be located at the relative position in the N photographing state. become.
However, the position at that time is the tele position, and the state shown in FIG. 10 shows a state in which the cam ring 6 has been driven to the wide position.

As described above, the finder of the camera according to the present embodiment is provided with the finder cams used in the conventional example in two areas and selectively used in conjunction with the screen size switching operation.
This makes it possible to make the viewfinder easy to see.

Next, the aforementioned cam ring 6 and finder cam 7
However, the relative position holding mechanism will be described in detail. The holding mechanism of this embodiment uses a click stop mechanism. As shown in FIGS. 10 and 12, the finder cam 7 has click grooves 7e and 7f, and the cam ring 6 has A recess 6e for holding the click spring 30 is formed. Further, the click spring 30 has a convex protrusion 30 for dropping into the click grooves 7e and 7f.
a is formed. Although not shown, the finder cam 7 is restricted in the radial direction so as to be slidable on the outer periphery of the cam ring 6, and the guide pins 6a, 6
b to be able to rotate in the circumferential direction.

In FIG. 10, since the projection 30a of the click spring 30 has fallen into the click groove 7e, the cam ring 6 and the finder cam 7 can rotate integrally in this state. When focusing on the guide pin 6a, it can be understood that the wide and telephoto states in the N shooting state can be set by moving the pin 6a within the range of the angle θ. When the cam ring 6 is rotated by an angle θP in the CW direction from the state shown in the drawing, the end face 7e of the finder cam 7 comes into contact with the main body stopper 4k, and then further.
When rotated, the projection 30a falls into the click groove 7f, and the fitting position is switched. By this switching operation, the relative positional relationship between the cam ring 6 and the finder cam 7 becomes a cam setting state for P photographing. Thereafter, when the position of the guide pin 6a of the cam ring 6 is returned from θC to θA, the wide state at the time of P photographing is obtained. Is set to

Similarly, when the cam ring 6 is turned in the CCW direction by the angle θN in the telephoto state of P photographing in FIG. 12, the end face 7d of the cam 7 comes into contact with the main body stopper 4i, and the cam ring 6 is further turned. As a result, the finder cam 7 rotates relatively to the cam ring 6, the projection 30a of the spring 30 switches from the click groove 7f to 7e and falls, and the relative positional relationship between the cam ring 6 and the finder cam 7 is The cam setting state for the N shooting mode is set. When the guide pin 6a of the cam ring 6 is returned to the position .theta.B, the telephoto setting state for N photographing is set.

FIG. 14 shows the operating states of the cam ring 6 and the finder cam 7 shown in FIGS. 10 and 12 collectively. In each setting state, the cam pins 11a and 12a correspond to the cam surfaces 7a and 7b. This indicates whether the area is slid on. Although the click stop mechanism is applied to the relative position holding mechanism in the present embodiment, a mechanism using a holding force by friction may be used.

Next, the finder cam 7 and the P ring 3
The cam ring 6 and the P ring 3 shown in FIG.
3 and an operation state development view of the finder cam 7 will be described. In FIG. 15, a line FL indicates an operation line of the cam pins 11a and 12a of the finder.

In FIG. 15, the state between the states Q1 and Q2 shows the state of the N photographing mode. The state Q1 is a telephoto state of zooming, and the state Q2 is a wide state. In this case, an arbitrary focal length can be obtained by driving the cam ring 6 within the range of the angle θ. At this time, the cam pins 11a and 11b of the finder frame slide along the cam surfaces 7a and 7b, and the finder optical system zooms correspondingly.
Since the contact surfaces 6c and 6d of the cam ring 6 do not act on the P ring 33, the N photographing state is maintained and the screen is kept in the N size.

Therefore, in order to switch to the P photographing mode,
In FIG. 15, the cam ring 6 is further rotated from the wide position by the angle θp in the CW direction to change from the state Q2 to Q3. By this operation, first, the end face 7e of the finder cam
Abuts on the main body stopper 4k, and the relative position of the finder cam 7 with respect to the cam ring 6 is switched to the P photographing mode position. At the same time, the contact surface 6 d of the cam ring 6 is
Is pressed, and the P-ring 33 rotates to the P photographing mode position. By this operation, the actual screen size becomes P
The size (panorama size) can be switched. At this time, the mask switching lever 13 of the finder unit is operated via the arm 33g by the rotation of the P ring 33, and the finder field frame is simultaneously switched to the field frame for P photographing. Subsequently, the cam ring 6 is reversed by the angle θp, and the state Q4
And This state is the wide state in the P shooting mode.

The state of the P photographing mode is maintained between the states Q4 and Q5, and the state Q4 is a zoom wide state.
Q5 enters a telephoto state. Also in this case, the focal length can be changed by driving the cam ring 6 within the range of the angle θ to obtain an arbitrary focal length. Also, the cam pins 11a, 11
b slides along the cam surfaces 7a and 7b, and the finder optical system changes its magnification accordingly. In this P photographing state, the magnification takes a larger value than in the case of N photographing as shown in FIG. . In this section, the cutout contact surfaces 6c and 6d of the cam ring 6 do not act on the P ring 33, so that the screen size does not change.

Further, in order to return to the N photographing mode, as shown in FIG.
To Q6. By this operation, first, the end face 7d of the finder cam comes into contact with the main body stopper 4i, and the relative position of the finder cam 7 with respect to the cam ring 6 is switched to the N photographing mode position. At the same time, the contact surface 6c of the cam ring 6 presses the operating arm 33f of the P-ring 33, and the P-ring 33 is rotated to the N shooting mode position to switch the actual screen size to the N size. At this time, the rotation of the P ring 33 operates the view switching lever 13 of the finder unit via the arm 33g, and the finder viewing frame is simultaneously switched to the N shooting field frame. Subsequently, when the cam ring 6 is reversed by the angle θN, the state is returned to the telephoto state of the N shooting mode in the state Q1.

In the above description, the photographing mode is switched from the state Q2 or Q5. However, the mode can be switched from an arbitrary focal length state.
In this case, the mode may be switched by rotating the P-ring 33 by a predetermined angle, and then the cam ring 6 may be returned to the original focal length position again.

As described above, the cam ring 6 is set in the normal use area,
That is, the finder magnification, the actual screen size, and the field frame can be switched in conjunction with each other by rotating the angle θp and θN beyond the wide and tele regions.

Next, a control circuit of the screen switching mechanism of the camera according to the present embodiment will be described. FIG. 16 is a main block diagram of the control circuit. The circuit includes a microcomputer 31, an actuator 32, and a screen switching mechanism 38.
, A position detecting means 34, a screen size switching instruction switch 35, and a pull-up resistor 36. In addition,
The actuator 32 corresponds to the zoom motor 10a of the driving source shown in FIG. 1, and the screen switching mechanism 38 has an actual screen size equal to or smaller than the P-ring 33 driven through the cam ring 6 shown in FIG. This is a mechanism for switching.
The position detecting means corresponds to the flexible substrate 25 and the contact piece 26 of the encoder pattern shown in FIG. 1, and detects the rotation angle of the cam ring 6, and thus the operating position of the screen switching mechanism. The instruction switch 35 operates in conjunction with an operation member of the external appearance of the camera (not shown) to select and instruct either the N or P photographing mode. The pull-up resistor 36 supplies a high-level signal to the microcomputer 31 when the switch 35 is off. The microcomputer 31 switches the actuator 3 based on the switching of the switch 35 from off to on.
2 will start.

FIG. 17 is a view for explaining the moving position of the photographing lens or the rotating position of the cam ring with respect to the operation state.
The horizontal axis in this figure indicates the moving position of the photographing lens or the rotation angle of the cam ring. The central area H10 is a wide-telephoto zooming area where the taking lens is extended.
Switching to the N shooting mode in which the screen size is N size (full size) is performed by moving to the switching position H11 (corresponding to the rotation angle θN in FIG. 15) and returning to the area H10 again.
The above switching is performed. Similarly, if the screen size is P
Switching to the P shooting mode, which is the size (panorama size), is performed from the area H10 to the switching position H12 (FIG. 1).
(Corresponding to the rotation angle θp of 5) and returning to the region H10 again, the above switching is performed.

Next, the processing operation of the control circuit will be described with reference to the flowchart of FIG. First, after the power is turned on, the photographing process is repeated in a loop from step S20 to step S21. Step S2 above
Instruction switch 3 for switching NP shooting mode in 1
If the output on of No. 5 is detected, the process jumps to step S22. In step S22, the current position data of the photographing lens group is detected by the position detecting means 34, stored in the memory of the microcomputer 31, and the flow advances to step S23. Then, in step S23, the currently set screen size is read from the memory and determined. If the size is N size, the process jumps to step S24, and if the size is P size, the process jumps to step S25.

In step S24, the cam ring 6 is rotated to the position H12 in FIG. 17, and the actual screen size is switched to the P size by the screen switching mechanism. At this time, the finder field frame is simultaneously switched to the field frame corresponding to the P photographing mode. Further, the position of the finder cam 7 relative to the cam ring 6 is also changed, and a finder magnification characteristic suitable for P photographing is set. Then, the process proceeds to step S26.

In step S25, the cam ring 6 is rotated to the position H11 in FIG. 17, and the actual screen size is switched to the N size by the screen switching mechanism. At that time, the finder field frame is simultaneously switched to the field frame corresponding to the N photographing mode. Further, the position of the finder cam 7 relative to the cam ring 6 is changed, and a finder magnification characteristic suitable for N photographing is set. These switching operations are as described above.

Then, the process proceeds to step S26. Subsequently, in step S26, the photographing lens group is returned to the position stored in step S22, the screen switching operation is completed, and the flow returns to the photographing processing in step S22.

As described above, according to the camera of this embodiment, a desired photographing screen can be switched immediately by giving only a screen switching instruction. Further, since the position of the photographing lens at the time of switching is stored as described above, it is possible to immediately return to the zoom position before switching after the switching is completed, which is extremely convenient. The camera of the present embodiment can be applied to a tele-wide two-focus switching camera and an electronic camera equipped with an optical finder, in addition to the cameras of the above-described embodiments.

[0054]

As described above, in the camera of the present invention, in the switching operation of the photographing screen, the screen switching mechanism and the field frame switching mechanism are driven by using the variable power drive motor through the variable power drive mechanism. Since the magnification setting of the viewfinder optical system is changed, the camera of the present invention uses a conventionally used photographing lens driving motor to switch the actual screen, switch the viewfinder field frame, and furthermore, the viewfinder magnification. Can be switched, which is advantageous in terms of cost, and has a remarkable effect such that the user can switch the screen by one-touch operation and obtain a viewfinder image which is easy to observe.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an outline of the structure of a camera according to the present invention.

FIG. 2 is a view showing a zoom state of a photographing optical system of the camera of FIG. 1;

FIG. 3 is a view showing a zoom state of a finder optical system of the camera of FIG. 1;

FIG. 4 is a longitudinal sectional view of a main part of a taking lens barrel of the camera of FIG. 1;

FIG. 5 is an exploded perspective view of a main part of a finder optical system of the camera shown in FIG. 1;

FIG. 6 is a front view of a screen switching mechanism in an N shooting mode of the camera according to the first embodiment of the present invention.

FIG. 7 is a sectional view taken along the line AA of FIG. 6;

FIG. 8 is a front view of a screen switching mechanism in the P shooting mode of the camera of FIG. 6;

FIG. 9 is a sectional view taken along the line BB of FIG. 8;

FIG. 10 is a longitudinal sectional view showing a relative positional relationship between a cam ring and a finder cam in the N photographing mode of the camera of FIG. 6;

FIG. 11 is a development view of the finder cam of FIG. 10;

12 is a longitudinal sectional view showing a relative positional relationship between a cam ring and a finder cam in a P photographing mode of the camera of FIG. 6;

FIG. 13 is a development view of the finder cam of FIG. 12;

FIG. 14 is a developed view showing a relative positional relationship between a cam ring and a finder cam in the N and P photographing modes of the camera of FIG. 6;

FIG. 15 is a development operation diagram of a cam ring and a finder cam showing a switching state of N and P photographing modes of the camera of FIG. 6;

FIG. 16 is a main block configuration diagram of a screen switching mechanism control circuit of the camera of FIG. 6;

FIG. 17 is a view showing the operation rotation position of a cam ring in the screen switching control of the camera of FIG. 6;

FIG. 18 is a flowchart of a screen switching control process of the camera of FIG. 6;

19A and 19B show respective visual field frames with respect to a photographing screen of a camera. FIG. 19A shows a visual field frame during normal photographing, and FIG.
9 (B) is a field frame at the time of panoramic shooting of a conventional camera,
FIG. 19C is a diagram showing a field frame at the time of panoramic shooting of the camera of the present invention.

[Explanation of symbols]

1 Mask A (screen switching mechanism) 2 Mask B (screen switching mechanism) 3, 33 P-ring (screen switching mechanism) 6 cam ring (magnification driving mechanism) 10a zoom motor (motor serving as a driving source of the magnification driving mechanism) 11b, 12b finder magnification lens ( Finder optical system) 13 Field frame switching lever (field frame switching mechanism) 16 Field mask (field frame switching mechanism)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-63034 (JP, A) JP-A-63-95429 (JP, A) JP-A-1-267624 (JP, A) JP-A-4- 113341 (JP, A) JP-A 2-48933 (JP, U) JP-A 63-54134 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03B 13/00-13 / 28 G03B 17/00 G03B 17/28

Claims (2)

(57) [Claims] 1. A variable power drive mechanism for driving a variable magnification optical system, a motor serving as a drive source of the variable power drive mechanism, a screen switching mechanism for changing the size of a captured screen, A finder optical system having a magnification ratio greater than that of the system, and a field frame switching mechanism for changing the size of a finder field frame provided in the finder optical system. , actuates the screen switching mechanism and the field frame switching mechanism, the
The zoom range of the zoom ratio of the finder optical system is
A camera characterized by switching according to the size of a field frame . Wherein said motor, said the variable power drive mechanism
When driven beyond the zoom mechanism of the photographing optical system, the zoom drive mechanism operates the screen switching mechanism and the field frame switching mechanism to switch the zoom range of the finder optical system. The camera according to claim 1.