JPH09197494A - Mechanism for adjusting indication rate of finder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism for adjusting an indication rate which can adjust an indication rate without deviation with respect to a subject image on a lens surface, which has a simple constitution, and which is excellent in practicality and facilitation. SOLUTION: A prism position adjusting screw 102 is movably attached to an image reversing optical system attaching part 83 freely forward and backward, and abuts on a triangle prism 80, on the other hand, a leaf spring 103 energizing the prism 80 forward is disposed to face oppositely, and the prism 80 is press-held between the screw 102 and the spring 103. When the indication rate is adjusted, the moving forward and backward amount of the screw 102 is adjusted and the prism 80 is finely moved in parallel with the perpendicular image-formation surface of the prism 80 so that the labellings reflected on the finder visual field of an eyepiece optical system is set on an adequate position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a finder which is equipped with a real image type optical system in which an objective optical system, a reversing optical system and an eyepiece optical system are arranged in that order, and particularly relates to a finder which is incorporated into a camera to function, and more particularly to a built-in finder. The present invention relates to the improvement of the indication rate adjusting mechanism.

[0002]

2. Description of the Related Art Generally, a finder uses a reversing optical system including a plurality of prisms to convert a subject image formed as a reversing image by an objective optical system including a plurality of lens groups into an erected image, which is then guided to an eyepiece optical system. Is configured as
The viewfinder field captured by the photographer with the eyepiece optical system
It should be as close as possible to the field of view taken by the taking lens.

The ratio of the part of the viewfinder field that matches the range of the image taken by the taking lens is usually called the indication ratio. In order to properly adjust this ratio, in the past, it was copied in the viewfinder. It was adjusted by making the entire objective optical system in a direction intersecting the optical axis while visually recognizing the marker so that the marker was set at an appropriate position.

[0004]

However, in order to move the objective optical system in the direction intersecting the optical axis,
That is, the lens surface is also biased with respect to the subject image, which causes a problem that the subject image is distorted in the eyepiece optical system.

As a solution to such a problem, for example, by arranging a reversing optical system in a direction orthogonal to the objective optical system and independently moving only the objective optical system in the optical axis direction, a real image is obtained. If the position is adjusted with respect to the inversion optical system after the surface, it is possible to obtain the indication ratio adjusting means without the bias of the subject image with respect to the lens surface. Not only the optical system, but the entire optical system, including the drive transmission system for that lens group, must be moved without error.In order to realize such a mechanism, the structure becomes complicated, and the cost and actual design In terms of aspect, it will cause a considerable disadvantage.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to perform an instruction rate adjustment without deviation with respect to a subject image on a lens surface, and yet it is easy to realize. It is an object of the present invention to provide an instruction rate adjusting mechanism having an excellent and simple structure.

[0007]

In order to achieve the above object, the pointing ratio adjusting mechanism of the present invention comprises a real image type finder optical system in which an objective optical system, a reversing optical system and an eyepiece optical system are arranged in that order. In the finder, the real image plane and the reversal optical system portion after the real image plane are held so as to be movable parallel to the real image plane.

With the above arrangement, when the pointing ratio is adjusted, the reversal optical system portion after the real image plane is set on the optical axis while visually recognizing the marker so that the marker imaged in the finder is set at an appropriate position. And a direction perpendicular to the optical axis.

In the above structure, the mechanism for movably holding the reversing optical system portion after the real image plane has a spring member for urging the reversing optical system portion in one direction, and the same direction as the urging direction of the spring member. And a screw member advancing in the opposite direction. Further, in this case, the spring member is
It can be constituted by a leaf spring.

Further, in the viewfinder in which the switching field frame is arranged along the real image plane, if the switching field frame is constructed so as to be movable integrally with the reversing optical system portion after the real image plane, It is possible to reliably prevent the displacement of the field frame due to the displacement of the reversing optical system portion, and it is also possible to simultaneously adjust the screen size other than the standard screen size.

Further, by forming the reversing optical system portion after the movable real image surface by an independent member, it is possible to prevent the eyepiece optical system from being affected after the instruction ratio adjustment.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a camera finder according to the present invention will be described below with reference to the drawings. 1 to 14 show a first embodiment of a finder according to the present invention, and FIG. 1 shows an appearance of a camera incorporating the finder of the present embodiment. The camera K shown in this figure has an automatic focus adjustment (hereinafter referred to as AF) function,
It is a lens shutter type zoom camera having an automatic exposure adjustment (hereinafter abbreviated as AE) function.

In FIG. 1A, 1 is a body,
A zoom lens 2 for photographing is mounted in the center of the body 1, and a grip portion 3 having a film loading chamber, an auto rewinder (neither shown), or the like is integrated with the body 1 at one end. Is formed in. Also,
A shutter button 4 is arranged on the upper surface of the grip portion 3. Further, a flash device 5 that emits strobe light is arranged on the other end side of the body 1.

As shown in FIG. 1B, a power switch 6, a zoom operation lever 7 and a field frame switching lever 8 are arranged in parallel on the back side of the body 1. The power switch 6 is mounted on the body 1 to turn on / off a power battery that supplies power to the drive system, display system, photometric system, etc. of the camera K.
For example, a push button. By rotating the zoom operation lever 7 to the left and right, it is possible to select the image magnification steplessly within a zoom range including telephoto, standard, and wide angle. The field frame switching lever 8 is
When any one of the three screen sizes H, C, and P is selected, the user operates the moderationally turning operation.

FIG. 15 schematically shows a screen size which can be photographed by the camera K shown in FIG. In this figure, the first screen size H indicated by a solid line frame has an aspect ratio of 1
The high-definition size is 6: 9, and in the present embodiment, the screen size H is used as a standard and can be switched to the second screen size C shown by a broken line and the third screen size P shown by a dashed line.

The second screen size C is called a classic size or the like and has an aspect ratio of 4: 3. Also, the third screen size P is commonly called a panorama size,
The aspect ratio is 2: 1. By operating the visual field frame switching lever 8 to select one of these, the image pickup surface of the film is switched, and in conjunction with this, the visual field of the finder F1 described later is also switched.

Returning to FIG. 1A, the zoom lens 2 for photographing
The objective window 9 of the finder F1 of the present embodiment is exposed above. In this way, the objective window 9 of the finder F1
Is located close to the photographing zoom lens 2 so that the field of view of the finder F1 can be changed.
You can get as close as possible to your vision.

Returning to FIG. 1 (B), the eyepiece window 10 of the finder F1 faces a position biased to the other end side of the body 1. By unevenly distributing the eyepiece window 10 in this way,
The body 1 can be prevented as much as possible from interfering with the protrusion of the user's nose when looking into the finder F1, and the shutter button 4 arranged on one end side is positioned opposite to the finder F1. The operability of the shutter button 4 while looking through the camera is improved.

However, in the finder F1, since the objective window 9 and the eyepiece window 10 are largely separated not only in the depth direction of the camera K but also in the lateral width direction, an image is formed in the finder F1 by the objective optical system. An image inversion optical system is incorporated to invert the real image and guide it to the eyepiece optical system. Further, the objective optical system is composed of a zoom optical system which is interlocked with the zooming operation of the photographing zoom lens 2, whereby the photographer can obtain a finder image that is substantially equal to the image on the film surface. It is like this.

FIG. 2 shows the assembled state of the finder optical system.
3 shows a state in which the finder F1 is disassembled, and FIG. 4 shows a cross section in an assembled state. As shown in these figures, the finder F1 of the present embodiment includes an objective optical system,
A real image type finder optical system including an inverting optical system and an eyepiece optical system is provided.

Reference numeral 11 denotes a finder case. The finder case 11 is equipped with an objective optical system, an image inverting optical system, an eyepiece optical system and the like. The objective optical system is a four-group zoom optical system including a first lens G1, a second lens G2, a third lens G3, and a fourth lens G4, and in the present embodiment, a high image magnification is provided. Has become. The image inverting optical system includes a Porro prism 12 and two triangular prisms 13 and 14, and the eyepiece optical system includes a single eyepiece lens G5.

In the finder optical system incorporated in the finder case 11, the incident light from the objective window 9 in the state of being assembled to the body 1 of the camera K is as shown by an optical path AX in FIG. First to fourth lens G
After being adjusted to an arbitrary image magnification by 1 to G4, the first prism 12a of the Porro prism 12 bends downward by 90 °, and further the second prism 12a bends horizontally by 90 ° to form a first image.
It is guided to the triangular prism 13 and then the second triangular prism 1
It is inverted at 4 to form an erect image and is guided to the eyepiece lens G5.

The finder case 11 can be formed of a synthetic resin molded product or a sheet metal processed product, and in the upper part of FIG. 3, a box-shaped objective optical system accommodating portion 15 and a rear part of the objective optical system accommodating portion 15 are provided. The image reversing optical system mounting portion 16 formed in a substantially orthogonal shape, the window frame 17 for mounting an eyepiece lens formed facing the back of the image reversing optical system mounting portion 16, and the like. Reference numeral 18 denotes a window which faces the objective window 9 of the body 1, and is opened at the front surface of the objective optical system accommodating portion 15.

The first lens G1 constituting the objective optical system is
In the first lens holder 19, the second and third lenses G2, G
3 is the second lens holder 20, and the fourth lens G4
Are fixed to the third lens holder 21, respectively.
These first to third lens holders 19 to 21 function as an optical holding member, and slide cylinders 19a, 20a and 21a are integrally formed at the lower ends thereof.

The slide cylinders 19a and 21a of the first and third lens holders 19 and 21 are slidably mounted on a common first lens suspension shaft 22 along the optical path (optical axis) AX, respectively, and the second lens holders. The slide cylinder 20a of 20 is slidably mounted on the second lens suspension shaft 23. Further, at the upper end portions of the first to third lens holders 19 to 21, the rotation stopping bosses 19b, which project substantially vertically,
20b and 21b are integrally provided.

The first lens holder 19 is provided with a bracket 24 projecting to the side of the slide cylinder 19a, and a slide cylinder member 25 is attached to the bracket 24 so as to be movable back and forth in the optical axis direction as described later. ing. The slide cylinder member 25 is mounted on the second lens suspension shaft 23 so as to be slidable in the optical axis direction. Cam followers 19c, 20c, 21c are provided on the slide cylinder member 25 attached to the second lens holder 20 and the slide cylinders 19a, 21a of the first and third lens holders 20, respectively.

Reference numeral 27 denotes a variable-magnification cam member consisting of a bar cam, which is mounted on a cam shaft 28 arranged parallel to the first and second lens suspension shafts 22 and 23 so as to move integrally in the optical axis direction. ing. The variable-magnification cam member 27 is formed with a first lens cam 27a, a second and third lens cam 27b, and a fourth lens cam 27c, and the first lens cam 27a.
Is the cam follower 19c of the first lens holder 19,
The cam followers 20c of the second lens holder 20 are attached to the second and third lens cams 27b, and the cam followers 21 of the third lens holder 21 are attached to the fourth lens cam 27c.
c are in contact with each other.

At the front end of the cam shaft 28, a cam gear 30 meshing with a drive transmission gear 29 provided at the output end of the zoom finder drive system of the camera K is mounted so as to rotate integrally with the variable-magnification cam member 27. And as shown in FIG.
The driving force generated by the rotation operation of the zoom operation lever 7 is transmitted to the cam gear 30 via the finder drive system of the camera K, and zooming is performed thereby. Reference numerals 31 and 31 are E rings for positioning the variable magnification cam member 27 and the cam gear 30 on the cam shaft 28. The cam gear 30
May be integrated with the variable-magnification cam member 27 or separate from it.

A tension spring 32 is stretched between the first lens holder 19 and the third lens holder 21, and the urging force of the tension spring 32 causes the first and third cam followers 19c and 21c to move to the first and third positions. Fourth lens cams 27a, 27
It is constantly pressed against c. A compression spring 33 is interposed between the slide cylinder 20b of the second lens holder 20 and the rear wall 15b of the objective optical system accommodating portion 15 of the finder case 11, and the biasing force of the compression spring 33 causes the compression spring 33 to move. , The second cam follower 20c is the second and third lens cam 27b.
Is constantly pressed against.

FIG. 5 shows the objective optical system in the finder case 1.
1 is a front view of the first lens G1 and a portion related to the first lens G1 in a state of being assembled in FIG. As shown in FIGS. 4 and 5, the bracket 24 of the slide tubular member 25
A guide shaft 25a is provided on the surface facing the and. The guide shaft 25a is fitted in a shaft insertion hole 24a provided in the bracket 24 so as to be slidable in the optical axis direction.

On the other hand, the bracket 24 is provided with a screw hole 24b, and the first adjusting screw 26 is screwed into the screw hole 24b, and the tip end surface of the screw is brought into contact with the front surface of the slide cylinder member 25. Then, the position of the first lens G1 in the optical axis direction can be finely adjusted by adjusting the amount of protrusion and retraction of the first adjustment screw 26, and thus the zooming error of the objective optical system can be absorbed. .

The camshaft 28 has a second adjusting screw 2 on the rear end side.
8a is carved and a screw head 28b for rotating the second adjusting screw is formed at the front end portion. This camshaft 2
Reference numeral 8 is inserted through a cam shaft insertion hole 34 formed in the front wall 15a of the objective optical system accommodating portion 15 of the finder case 11,
The second adjusting screw 28a is screwed into the nut 35 attached to the rear wall 15b. Then, by rotating the screw head 28b to move the cam shaft 28 forward and backward in the optical axis direction and adjusting its front-rear position, the position of the variable magnification cam member 27 is adjusted.

By providing such a position adjusting mechanism of the cam shaft 28, it is possible to adjust the diopter by moving the position of the objective optical system in the optical axis direction at the assembly stage. That is, the second adjusting screw 2 provided on the cam shaft 28 itself.
By providing 8a, by adjusting the amount of advance / retreat of the second adjusting screw 28a from the nut 35, the positions of the first and fourth lenses G1, G4 in the entire finder optical system are adjusted, and the entire finder optical system is adjusted. The diopter is adjusted appropriately.

The variable magnification cam member 27 shown in FIG. 6 is shown in FIG.
As is apparent from the external view and the development view of (B), the first lens cam 27a is formed by utilizing the large-diameter front end step of the variable power cam member 27, and the second lens cam 27a is formed. 27b
Is formed by utilizing the rear step portion of the large diameter portion of the variable power cam member 27.

FIG. 7 shows a cam 27 for the first to third lenses.
The cam curves a to 27c are shown, and as shown in this figure, the first lens G1 following the first lens cam 27a basically does not move as shown by the locus I. In contrast,
The second and third lenses G2 and G3 that follow the second and third lens cams 27b follow a locus II that separates from the first lens G1 from the short focus (wide) W side to the long focus (tele) side,
The fourth lens G4, which follows the fourth lens cam 27c, follows a locus III in which the vicinity of the standard approaches.

The objective optical system having such a configuration is inserted into the objective optical system accommodating portion 15 of the finder case 11 from below. In this state, each lens holder 19-2
The detent bosses 19b to 21b of No. 1 are the objective optical system accommodating portion 1
5 is slidably fitted in the long hole 36 formed in the upper wall 15c of the upper wall 15c, and the front and rear side walls 15a, 1 of the objective optical system accommodating portion 15 are inserted.
The first lens suspension shaft 22 is supported in the first shaft support holes 37, 37 formed in 5b, and the front and rear side walls 15 are also provided.
The second shaft support holes 38, 38 formed in the holes a, 15b
By supporting the lens suspension shaft 23, the first to fourth
The lenses G1 to G4 are supported so as to be linearly slidable in the optical axis direction.

FIG. 8 schematically shows the arrangement of each member of the image inverting optical system. As shown in FIGS. 3 and 8, the Porro prism 12 includes a first prism 12a and a second prism 12b that are vertically joined to each other, and is fitted into the image inverting optical system mounting portion 16 of the finder case 11 from above. It is attached. The first triangular prism 13 has a second partition of the Porro prism 12 with the partition wall 16a in the image inverting optical system mounting portion 16 interposed therebetween.
It is installed at a position facing the prism 12b. Further, the second triangular prism 14 is integrally mounted on the first triangular prism 13. Then, the eyepiece lens G5 is attached to the eyepiece lens attachment window frame 17, and the upper end open surface of the image inverting optical system attachment portion 16 is covered with the lid 39.

In the image inversion optical system incorporated in the finder case 11, the optical axis AX which is incident from the objective optical system is used.
Is the vertical surface 1 of the first prism 12a of the Porro prism 12.
It is incident on 2a ₁ , is refracted in the vertical direction at the 45 ° inclined surface 12a ₂ , is refracted in the horizontal direction at the 45 ° inclined surface 12b ₁ of the second prism 12b, and passes through the vertical image forming surface 12b ₂ which is the real image surface, The light enters the first triangular prism 13 and, in the same manner, reaches the second triangular prism 14 from the triangular prism 13 and inverts the image to form an erect image, which reaches the eye of the photographer through the eyepiece lens G5.

In the finder F1 of this embodiment, the field frame switching mechanism for switching the field of view of the finder F1 to the first to third screen sizes shown in FIG. It is arranged by utilizing the empty space of the optical system. That is, since the image inverting optical system mounted on the finder case 11 is configured such that four groups of two triangular prisms are assembled, when incorporating this into the camera K, the inside of the box-shaped body 1 is formed. Will occupy a rectangular parallelepiped space.

However, since the upper surfaces of the first prism 12a and the second triangular prism 14 of the Porro prism 12 are inclined at 45 °, they are between the ceiling surface of the body 1 and the inclined upper surfaces of these prisms 12a, 14. The extra space S is inevitably generated. On the other hand, the operated portion 40 of the visual field frame switching mechanism is interposed between the Porro prism 12 and the first triangular prism 13 as described later. In consideration of these configurations, in the present embodiment, the drive portion 41 of the field frame switching mechanism that drives the operated portion 40 is arranged by using the spare space S, whereby the camera K is further downsized. , Is trying to be compact.

Specifically, the drive unit 41 of the field frame switching mechanism.
Are arranged so as to be accommodated in the extra space S on the second triangular prism 14. Drive unit 41 of this field frame switching mechanism
Are configured to interlock with the field frame switching lever 8. Further, the operated part 40 operates so as to switch the visual field in the finder F1 in conjunction with the movement of the drive part 41. Returning to FIG. 3, the image forming surface 12 of the second prism 12b.
Between the b ₂ and the triangular prism 13, the first and second visual field frame pieces 42 and 43 constituting the visual field frame switching mechanism actuated portion 40 can move forward and backward in a direction orthogonal to the optical axis incident from the Porro prism 12. It is installed in.

FIG. 9 shows a specific construction of the visual field frame switching mechanism. As shown in this figure, the first and second visual field frame pieces 4
2, 43 can be produced by bending a plate-like piece, and the first field-of-view frame piece 42 is formed by cutting out a second field-of-view restriction window 42a corresponding to the second screen size C in the lower half part. The first arm 42b is formed from the upper end.
Is extended in a state of being bent at a substantially right angle. Similarly, the second visual field frame piece 43 is formed by cutting out a third visual field regulating window 43a corresponding to the third screen size P in the lower half portion, and the second visual field frame piece 43 is shorter than the first arm 42b from the upper end portion.
The arm 43b is extended so as to be bent at a substantially right angle.

Further, at the tips of the first and second arms 42b and 43b, a cam follower 42 formed of a short bent piece is provided.
c and 43c are formed. The first and second field frame pieces 42 and 43 are rotatably supported at their base ends by a common support shaft 44 in a direction substantially orthogonal to the optical axis.

The drive unit 41 of the field frame switching mechanism is composed of a rotary cam mechanism. That is, the rotary cam mechanism includes a rotary shaft 45 formed substantially vertically and the rotary shaft 4
First and second cam pieces 46, 4 extending from 5 in a substantially horizontal direction
7, and a cam member 49 having an operated arm 48 extending from the first cam piece 46, and the first and second cam members 49.
A cam biasing spring 50 that constantly biases the cam pieces 46, 47 in a direction of contacting the cam followers 42c, 43c of the field frame pieces 42, 43, and the operated arm 48 rotates in conjunction with the field frame switching lever 8. By rotating about the shaft 45, the first and second cam pieces 46, 47 are horizontally rotated. The support shaft 44 and the rotation shaft 45 are supported by the finder case 11.

Field frame frame urging springs 51 and 52 are interposed between the first and second field frame pieces 42 and 43 and the image inversion optical system mounting portion 16 of the finder case 11, and these field urging springs 51 and 52 are urged. The urging forces of the springs 51 and 52 urge the first and second field-of-view frame pieces 42 and 43 in such a direction as to always enter the field of view.

Further, the partition wall 16 of the image reversal optical system mounting portion 16
a includes a notch window 16b which is a part of a first field-of-view restriction window (not shown) corresponding to the first screen size H which is the standard screen size shown in FIG. In the state where the lid 39 is covered on the mounting portion 16, the second prism image plane of the Porro prism 12 is formed by the notch window 16b of the partition 16a and the partition (not shown) formed on the lower surface of the lid 39. A first visual field regulating window is formed at a portion facing 12b ₂ .

FIG. 10 shows the movement of the cam member 49 of the visual field switching mechanism. In FIG. 10A, the visual field frame switching lever 8 shown in FIG. In the case of switching, (B) shows the case where the field frame switching lever 8 is set to the position of H and the first screen size which is the standard size is set.
(C) sets the field frame switching lever 8 to the P position and the third
The screen sizes are shown respectively.

In the standard size state of FIG. 10 (B),
Cam followers 55, 5 of the first and second field frame pieces 42, 43
6 are both on the cam ridges of the first and second cam pieces 46 and 47 of the cam member 49, whereby the first and second view frame pieces 4 are provided.
2 and 43 are retracted to a position outside the field of view where both 42 and 43 overlap, against the urging force of the urging springs 51 and 52, and the first field limiting window is opened, and the eyepiece window 10 is opened. The field of view seen from corresponds to the first screen size H.

When the field frame switching lever 8 is switched to the position C from the set state of the standard first screen size H,
The movement of the field frame switching lever 8 is transmitted to the operated arm 48, and the cam member 49 rotates around the rotation shaft 45 in the first direction, that is, in the direction indicated by the solid arrow r ₁ in FIG. (A)
As shown in, the cam follower 42c of the first visual field frame piece 42
Only the second cam is released from the cam lobe of the first cam piece 46, the first field frame piece 42 is rotated by the urging force of the urging spring 51 to enter the field of view, and the second field control window is placed on the first field control window. 42a overlaps, and the visual field seen from the eyepiece window 10 is the second screen size C.
It corresponds to.

When the field frame switching lever 8 is switched to the position P from the set state of the first screen size H, the movement of the field frame switching lever 8 is transmitted to the operated arm 48, and the cam member 49 is moved. 10B, which is the _second direction, rotates in the direction of the broken line arrow r ₂ in FIG. 10B, and as shown in FIG. 10C, only the cam followers 43c of the second field frame piece 43 have the second cam pieces 47.
Of the second field frame 43 from the cam mountain of the urging spring 52.
Is rotated by the urging force of the eye to enter the visual field, the third visual field regulating window 43a is overlapped on the first visual field regulating window, and the eyepiece window 10
The field of view viewed from corresponds to the third screen size P.

As described above, in the visual field frame switching mechanism of the present embodiment, since the first and second visual field frame pieces 42 and 43 enter the visual field in the same direction, both of them in the standard size are 42 and 43.
When both are retracted from the field of view, they are also retracted in the same direction, so the retracted space can be saved.
Further, since the urging direction of the urging springs 51 and 52 is also the approach direction, if a stopper means is provided at an appropriate position when any of the field frame pieces 42 and 43 is in the approach state, the field frame within the field of view can be obtained. There is no displacement of the pieces 42, 43.

As shown in FIG. 11, the finder F1 of the present embodiment is an AF constructed separately from the body 1.
The relative position of the module A can be adjusted, and it is supported integrally with the body 1.
The entire unitary structure with the module A is adjustably supported with respect to the body 1.

That is, A is on the bottom of the finder F1.
The mounting guide plate 53 of the F module A is attached,
The AF module A is supported on the mounting guide plate 53. Mounting pins 54a and 54b are provided at two side surfaces of the AF module A facing the finder F1. On the other hand, the pin insertion hole 5 is provided on the finder case 11 side.
5a and a pin insertion slot 55b are provided.

When the AF module A is attached to the finder F1, one attachment pin 54a is attached to the pin insertion hole 5
5a, the other mounting pin 54b is fitted into the pin insertion long hole 55b, and the other mounting pin 54b is allowed to move vertically in the pin insertion long hole 55b with one mounting pin 54a as a fulcrum. Then finder F1
In order to match the field of view of the AF module A with the distance measurement sensitivity range of the AF module A, the height position of the other mounting pin 54b is adjusted in the pin insertion slot 55b, and the mounting guide plate 5 is adjusted at the matched height position.
3 and the AF module A are fixed by using a known means such as inserting a spacer.

The finder F1 is set to A as described above.
After mounting the F module A, the F module A is integrally attached to the body 1 of the camera K. Returning to FIG. 3, in the finder case 11, the support brackets 56a to 56a are provided at three places, namely, two places on the left side bottom surface front and rear and one place on the right side bottom side rear end part.
56c is provided so as to project in the horizontal direction. And
When attaching the finder F1 and the AF module A to the body 1, these support brackets 56a to 56c
Align with the screw hole 59 formed on the body 1,
The compression springs 57a to 57c are respectively interposed and then fixedly supported by screws 58a to 58c.

In performing the screw fixing, the tightening amount of each of the screws 58a to 58c is adjusted, and the compression spring 5
The position of the finder F1 with respect to the body 1 is properly maintained by the spring biasing forces of 7a to 57c. As a result, the finder F1 and the AF module A are supported at the proper positions of the body 1 at three points without any error while the mutual positional relationship is properly maintained. In addition, finder F
The 3-point support of 1 is the best because it is easy to adjust,
The number of points is not necessarily limited to three.

Returning to FIG. 2, the first lens cam 27a of the variable-magnification cam member 27 has a cam portion 2 reaching the tele-macro region.
7at can be set. In this tele-macro region, as shown by the cam curve in FIG. 7, the amount of extension of the first lens G1 becomes large, and along with this, focusing correction becomes necessary.

12 to 14 show an example of a diopter adjusting mechanism which realizes focusing in the entire area including the telemacro area. First lens G constituting the objective zoom optical system
The lens holder 60 of i and the lens holder 61 of the second lens Gj are slidably fitted to a common lens suspension shaft 62. A tension spring 63 is stretched between the lens holders 60 and 61.
By the urging force of the first and second cam followers 60a, 61
a is constantly in pressure contact with the first and second lens cams 64a and 65a.

The first lens cam 64a is formed on the first variable magnification cam member 64, and the second lens cam 65a is formed on the second variable magnification cam member 65. These variable-magnification cam members 64 and 65 are mounted on a common cam shaft 66 arranged parallel to the lens suspension shaft 62 so as to move integrally in the optical axis direction, and as shown in FIG. Guide pins 64b, 64b protruding from the variable power cam member 64 are slidably fitted in guide holes 65b, 65b formed in the second variable power cam member 65.

On the side of the lens suspension shaft 62, a connecting lever suspension shaft 67 parallel to the lens suspension shaft 62 is rotatably mounted on the finder case 11, and the suspension shaft 67 has first and second diopter correction cam followers. 68a and 68b are slidably mounted. A diopter correction cam shaft 69 parallel to the connecting lever suspension shaft 67 is provided further to the side of the connecting lever suspension shaft 67.
1 is rotatably mounted on the suspension shaft 1, and a diopter correction cam member 70 is mounted on the suspension shaft 69 so as to rotate integrally therewith.

The first diopter correction cam follower 68
a is the end surface of the first variable power cam member 64 and the first cam 70a of the diopter correction cam member 70, and the second diopter correction cam follower 68b is the first variable cam member 65. The end surface facing the end surface of the double cam member is in contact with the second cam 70b of the diopter correction cam member 70, respectively.

At one end of the diopter correction cam shaft 69, a cam gear 72 meshing with a drive transmission gear 71 provided at the output end of the zoom finder drive system of the camera K rotates integrally with the diopter correction cam member 70. Mounted on the connecting lever cam shaft 67, an intermediate gear 73 meshing with the drive transmission gear 71 is attached to the first and second diopter correction cam followers 68a, 6a.
8b and the cam shaft 66.
Includes a zoom gear 74 that meshes with the intermediate gear 73.
It is mounted so as to rotate integrally with the second variable-magnification cam members 64 and 65, and the driving force generated by the rotation operation of the zoom operation lever 7 is generated by the finder drive system of the camera K and the drive transmission gear 7.
1, the cam gear 72, the intermediate gear 73, and the zoom gear 74.
To the finder, which causes the viewfinder to be zoomed.

At the other end of the diopter correction cam shaft 69, a cam gear 76 meshing with a drive transmission gear 75 provided at the output end of the focusing drive system of the camera K rotates integrally with the diopter correction cam shaft 69. The rotational drive force of the focusing drive system of the camera K is transmitted to the cam gear 76 via the drive transmission gear 75. Reference numeral 77 is a C ring for positioning the plurality of gears on each shaft.

In the diopter adjusting mechanism having such a structure, it is possible to deal with the entire focus including the telemacro region. That is, the first and second variable-magnification cam members 64 and 65 are fixed at proper intervals in the normal zoom area, but when zooming enters the telemacro area, the data measured by the AF module A or the focus operation is performed. The focus drive transmission gear 75 rotates in response to the manual operation of the ring, and the first and second diopter correction cam followers 68a, 68b move in accordance with the movement of the diopter correction cam member 70 following this.
The first and second variable-magnification cam members 64 and 65 move so as to expand or contract by an amount corresponding to the focus adjustment at that time, whereby the amount of extension of the first lens Gi is corrected.

In the embodiment shown in FIGS. 12 to 14,
The cam mechanism for driving the objective optical system at the time of focal length adjustment and the further cam mechanism for driving the cam mechanism for driving the objective optical system at the time of zoom are the diopter correction cam mounted on the diopter correction cam shaft 69. Although the member 70 is also used, both members may be configured by different cam mechanisms.

16 to 23 show a second embodiment of the finder according to the present invention. Like the finder F1 of the above-described embodiment, the finder F2 of the present embodiment includes an objective optical system including a zoom optical system, a reversing optical system, and a real-image finder optical system including an eyepiece optical system. The image magnification of the system is set smaller than that of the present embodiment. It should be noted that it can be incorporated in a lens shutter type zoom camera similar to the camera K shown in FIG.

The finder F2 of the present embodiment is composed of a unit formed separately from the body 1, and is adjustable with an AF module A also formed separately from the body 1, and with respect to the body 1. The finder F2 and the AF module A are integrally supported by the body 1 so as to be adjustable.

An image reversing optical system for reversing a real image formed by the objective optical system and guiding it to the eyepiece optical system is incorporated in the finder F2. Further, the objective optical system is composed of a zoom optical system which is interlocked with the zooming operation of the photographing zoom lens 2, whereby the photographer can obtain a finder image that is substantially equal to the image on the film surface. It is like this.

FIG. 16 shows the finder F2 in a disassembled state. As shown in this figure, the finder F2 of the present embodiment includes a real image type finder optical system including an objective optical system, a reversing optical system, and an eyepiece optical system.
The viewfinder is composed of a unit that is configured separately from the body 1 of the camera K, is adjustable with an AF module A that is also configured separately from the body 1, and is supported integrally with the body 1. The F1 and the AF module A as a whole are integrally supported on the body 1 so as to be adjustable.

Reference numeral 78 denotes a finder case, and an objective optical system, an image inverting optical system, an eyepiece optical system and the like are mounted on the finder case 78. The objective optical system is a two-group zoom optical system including a first lens Ga and a second lens Gb, and is set to an image magnification of about 2.5 to 3.0 times in this embodiment. The image inverting optical system includes a Porro prism 79, a triangular prism 80, and a mirror 81. Further, the eyepiece optical system includes a single eyepiece lens Gc.

In the finder optical system incorporated in the finder case 78, the incident light from the objective window 9 in the state of being assembled to the body 1 is the first optical axis of the objective optical system as shown by the optical axis AX in FIG. First and second lenses Ga and Gb
After being adjusted to an arbitrary image magnification by, the first prism 79a of the Porro prism 79 bends downward by 90 °, and further the second prism 79b bends horizontally by 90 ° and is guided to the triangular prism 80, and then the mirror. The image is inverted at 81 to form an erect image and is guided to the eyepiece lens Gc.

The finder case 78 can be formed of a synthetic resin molded product or a sheet metal processed product.
A box-shaped objective optical system accommodating portion 82 having an opening on the lower surface side, an image inverting optical system mounting portion 83 formed in a substantially orthogonal shape behind the objective optical system accommodating portion 82, and the like.

FIG. 17 shows an objective optical system and a cam mechanism for driving the objective optical system. As shown in this figure, the first lens Ga constituting the objective optical system is a first lens holder 84a.
In addition, the second lens Gb is the second lens holder 84b.
It is stuck to. These lens holders 84a, 8
Slide tubes 85a and 85b are formed at the lower end of 4b, and these slide tubes 85a and 85b are slidably mounted on a common lens suspension shaft 86. In addition, detent bosses 87a and 87b that project substantially vertically are formed at the upper ends of the first and second lens holders 84a and 84b.

Further, a first cam follower 88a is integrally provided on the slide cylinder 85a of the first lens holder 84a, and a second cam follower 88b is integrally provided on the slide cylinder 85b of the second lens holder 84b. Reference numeral 89 denotes a variable-magnification cam member composed of a bar cam, which is a lens suspension shaft 86.
It is mounted on a cam shaft 90 which is arranged in parallel with. The first lens cam 89a is provided on the peripheral surface of the variable power cam member 89.
And a second lens cam 89b are formed, the first lens cam 89a is provided with a first cam follower 88a, and the second lens cam 89b is provided with a second cam follower 88a.
b are in contact with each other.

In the figure of the cam shaft 90, the camera K is provided at the front end.
A cam gear 91 for interlocking with the drive system of the camera is mounted so as to rotate integrally with the variable-magnification cam member 89. The driving force generated by the rotation operation of the motor built in the camera K or the zoom operation lever 7 is It is transmitted to the variable magnification cam member 89 via the K drive system and the cam gear 91. In addition,
The cam gear 91 may be configured integrally with or separately from the variable power cam member 89, and the cam gear 91 can be manually rotated by interlocking with the operation drive system. 92 is a first and second lens holder 84
It is a tension spring adjusted between a and 84b, and the urging force of the tension spring 32 causes the first and second cam followers 88 to move.
The a and 88b come into pressure contact with the first and second lens cams 89a and 89b at correct positions.

The objective optical system having such a configuration is inserted from below into the objective optical system accommodating portion 82 of the finder case 78, and the detent bosses 87a and 87b of the lens holders 84a and 84b are inserted into the objective optical system accommodating portion 82. The lens suspension shaft 86 is slidably fitted in a long hole 93 formed in the upper wall 82a, and the lens suspension shaft 86 is supported by shaft support holes 94, 94 formed in the front and rear side walls 82b, 82b of the objective optical system accommodating portion 82. As a result, the first and second lenses Ga and Gb are supported so as to be linearly movable in the front-rear direction.

The cam shaft 90 has a cam position adjusting screw 95, which will be described later, attached to the front end thereof, and a cam position adjusting compression spring 96 fitted to the rear end thereof, and then the objective optical system accommodating section side wall 82.
It is supported by a screw hole 97 and a support hole 98 formed in b and 82b. By incorporating the objective optical system in the housing portion 82 in this way, the cam position adjusting compression spring 96
The rear side wall 82b of the objective optical system accommodating portion and the rear end surface of the variable power cam member 89 are pressed against each other, and the variable power cam member 89 is pressed against the front cam position adjusting screw 95 via the cam gear 91.

Thus, in the assembly stage, by adjusting the amount of advance / retreat from the screw hole 97 of the cam position adjusting screw 95, the positions of the first and second lenses Ga and Gb in the entire finder optical system are adjusted, and the finder is adjusted. It is possible to properly adjust the diopter of the entire optical system. That is, when adjusting the diopter of the finder optical system, it suffices to correct one of the lens positions included in the optical system, but in the present embodiment, the positions of the first and second lenses Ga and Gb on the optical axis. The position of the entire cam shaft 90 is adjusted in the optical axis direction in order to adjust the position of the cam, and this is performed by advancing and retracting the cam position adjusting screw 95, thereby realizing accurate diopter adjustment with a simple mechanism. Reference numeral 99 is a window portion that faces the objective window 9 of the body 1.

FIG. 18 schematically shows the arrangement of each member of the image inverting optical system. As shown in FIGS. 16 and 18, the Porro prism 79 includes a first prism 79 a and a second prism 7 a.
9b are joined vertically, and are fitted into the image reversing optical system attachment portion 83 of the finder case 78 from above and attached. Further, the triangular prism 80 is incorporated at a position facing the second prism 79b of the Porro prism 79 with the partition wall 83a in the image inverting optical system mounting portion 83 interposed therebetween. Further, the mirror 81 is fixed along the inclined upper surface of the inclined wall 83b formed at the right end of the image inverting optical system mounting portion 83. The eyepiece lens Gc is an eyepiece lens mounting window 1 formed at the end of the finder case 78 facing the mirror 81.
Fixed to 00.

In the image inversion optical system incorporated in the finder case 78, the optical axis AX which is incident from the objective optical system is used.
Is the vertical surface 7 of the first prism 79a of the Porro prism 79.
It is incident on 9a ₁ , is refracted in the vertical direction at the 45 ° inclined surface 79a ₂ , is refracted in the horizontal direction at the 45 ° inclined surface 79b ₁ of the second prism 79b, and passes through the vertical image forming surface 79b ₂ which is the real image surface, It is incident on the triangular prism 80, and further, the triangular prism 80
From the mirror to the mirror 81, the image is inverted to form an erect image, which reaches the eye of the photographer from the eyepiece lens Gc.

In the finder F2 of this embodiment, the position of the triangular prism 80 is adjusted at the assembly stage in order to adjust the indication rate. As is well known, the instruction rate is finder F2
Indicates the ratio of the portion of the field of view that matches the range captured by the zoom lens 2 for photographing. In order to adjust the ratio appropriately, the inversion optical system after the vertical imaging plane 79b _{2 of} the second prism 79b, that is, The triangular prism 80 is held so that it can be moved in parallel to the vertical image plane 79b ₂ , that is, in the direction perpendicular to the optical axis. By moving this triangular prism 80, the instruction rate can be adjusted. Is going.

That is, the screw hole 1 is formed in the front side wall 83c of the image inverting optical system mounting portion 83 in which the triangular prism 80 is incorporated.
01 is provided, and the prism position adjusting screw 102 is screwed into the screw hole 101. Further, between the triangular prism 80 and the rear wall 78a of the finder case 78,
A leaf spring 103 for urging the triangular prism 80 forward is interposed, and the triangular prism 80 is pressure-held between the prism position adjusting screw 102 and the leaf spring 103.
Then, at the time of assembly, when the instruction rate is adjusted, the advancing / retreating amount of the prism position adjusting screw 102 is adjusted so that the triangular prism 80 is minutely moved so that the marker in the viewfinder field of the eyepiece optical system is set at an appropriate position. To move.

In this case, the prism position adjusting screw 1
When the amount of advance / retreat of 02 is adjusted, only the triangular prism 80 moves, and the relative positional relationship with the mirror 81 held in a stationary state slightly shifts. However, the reflective surface area of the mirror 81 is smaller than the effective surface of the triangular prism 80. Since the size is set large enough to cover, the reversing optical system will not be hindered.

The finder F2 of the present embodiment is equipped with a field frame switching mechanism for switching the field of view of the finder F2 to the first to third screen sizes in association with the operation of the field frame switching lever 8. The field frame switching mechanism includes a drive unit 104 that interlocks with the field frame switching lever 8 and the drive unit 1.
It is composed of an actuated portion 105 which switches the field of view in the finder F2 in conjunction with the movement of 04. Returning to FIG. 16, between the image forming surface 79b ₂ of the second prism 79b and the triangular prism 80, the first and second visual field frame pieces 106 and 107 of the visual field frame switching mechanism actuated portion 105 are orthogonal to the optical path. It is arranged so that it can move back and forth in the direction of movement.

The image inverting optical system mounted on the finder case 11 includes three groups of two triangular prisms and a tilt mirror 81.
Since they are configured in a manner that they are gathered, a marginal space Sa is inevitably generated between the ceiling surface of the body 1 and the inclined upper surfaces of the prisms 12a and 14. On the other hand, the actuated portion 105 of the visual field frame switching mechanism is interposed between the Porro prism 12 and the first triangular prism 13 as described later.

In consideration of these configurations, in the present embodiment,
The drive unit 104 is arranged in the spare space Sa. Specifically, as shown in FIG. 19, the drive unit 104 of the field-of-view frame switching mechanism is arranged so as to be contained in the spare space Sa on the mirror 81. Further, the actuated portion 105 is configured so that the whole of the actuated portion 105 moves integrally with the triangular prism 80 so as to follow the instruction rate adjusting operation by the prism position adjusting screw 102. The frame is not misaligned. In addition, screen sizes other than the standard screen size can be adjusted at the same time.

FIG. 20 shows a mounting structure of the field frame pieces 106 and 107. In this figure, 108 is a base plate fixedly mounted on the second prism 79b of the Porro prism 79, 109 and 110 are the first and second field frame pieces 106,
Left and right fixed frame pieces serving as first and second members arranged on both sides of 107 so as to sandwich both frame pieces 106 and 107. The base plate 108 may be integrally formed with the second prism 79b.

The left and right fixed frame pieces 109 and 110 respectively have a first screen size H, which is the standard screen size shown in FIG. 15, at the lower ends facing the image forming surface 79b ₂ of the second prism 79b. The field-of-view restriction window 111 is cut out, and the first field-of-view frame piece 106 has a second field-of-view restriction window 112 corresponding to the second screen size C at the lower end portion facing the first field-of-view restriction window 111, and the second field-of-view frame piece 106 also has a second area. At the lower end of the visual field frame piece 107, a third visual field regulating window 113 corresponding to the third screen size P is provided.
Each is cut out.

Each frame piece 106, 107, 10 of the base plate 108
A fulcrum pin 114 serving as a fulcrum of rotation is provided on the upper end portion on the side facing the 9, 110. On the other hand, the first and second visual field frame pieces 106 and 107 and the left and right fixed frame pieces 109 and 110 are respectively provided with pin insertion holes 115. By inserting these pin insertion holes 115 into the fulcrum pins 114, Each frame piece 106, 107, 109, 110 is the base plate 1
It is attached to 08. In addition, the left and right fixed frame pieces 109, 1
Numeral 10 is fixed because the contour portion is regulated by the inner method of the finder case 78, and the first and second view frame pieces 1 are fixed.
06 and 107 are swingably suspended around the fulcrum pin 114.

Further, both sides of the fulcrum pin 114 of the base plate 108, and the pin insertion holes 11 of the left and right fixed frame pieces 109 and 110.
On both sides of 5, the first and second swing levers 126,
A vertically long oblong hole 116 for inserting 127 (see FIG. 21) is formed. The long hole 116
Is set to a width that allows movement of the actuated portion 105 by adjusting the instruction rate when the swing levers 126 and 127 are inserted.

A horizontally elongated hole 117 for inserting the first swing lever 126 is provided in front of the pin insertion hole 115 of the first field frame piece 106, and a pin insertion hole 1 of the second field frame piece 107 is inserted.
On the rear side of 15, there are formed inclined elongated holes 118 for inserting the second swing lever 127, respectively.

FIG. 21 shows the structure of the drive unit 104 of the field frame switching mechanism, and FIG. 22 shows the assembled state of the field frame switching mechanism. In these figures, 119 is a swing switching mechanism, and 120 is a field frame switching cam as a cam member for operating the swing switching mechanism 119. The swing switching mechanism 119 includes the first and second swing members 121, 1 as rotary levers.
22 are provided. Each swing member 121, 122,
The field frame switching cam 12 is attached to the boss portions 123, 123, respectively.
The cam followers 124 and 125 as arms that come into contact with the zero cam ridge 120a and the swing levers 126 and 127 are integrally provided.

Then, the swing switching mechanism 119 rotatably inserts the common swing shaft 128 with the boss portions 123, 123 of both swing members 121, 122 facing each other, and at the same time, clicks fitted on the swing shaft 128. The spring 129 urges the cam followers 124 and 125 of both swinging members 121 and 122 in a closing direction.

Swing lever 126 of first swing member 121
Is the base plate 108, the front long hole 116 of the left fixed frame piece 109,
The horizontally elongated hole 117 of the first field frame piece 106 and the right fixed frame piece 1
10 is inserted into the front long hole 116, and the swing lever 127 of the second swing member 122 is provided with the base plate 108, the rear long hole 116 of the left fixing frame piece 109, and the inclined shape of the second view frame 107. The long holes 118 and the right fixed frame piece 110 are inserted through the rear long holes 116, respectively, and the direction of entry, that is, the first or second view frame piece 106, is urged by the urging force of the click spring 129.
Alternatively, 107 is biased toward the entry position side where the field-of-view restriction window 112 or 113 overlaps the first field-of-view restriction window 111.

As described above, since the biasing direction of the click spring 129 is the approaching direction, if any of the field frame pieces 106 and 107 is in the approaching state, if stopper means is provided at an appropriate position, the field of view will be within the field of view. Field frame piece 10
No displacement of 6 and 107 occurs.

On the other hand, the field-of-view frame switching cam 120 has the rotating shaft 130 at the center and the cam crest 120 on the cylindrical peripheral surface.
In addition, a notch engaging portion 131 as an operated portion that engages with the field frame switching lever 8 is provided on one end side, and the peripheral surface having the cam crest 120a has both the swinging members. It is rotatably arranged at a position facing the swing switching mechanism 119 so as to come into contact with the cam followers 126, 127 of 121, 122.

FIG. 23 shows the operation of the field frame switching mechanism. FIG. 1A shows a mode of the field frame switching mechanism when the field frame switching lever 8 shown in FIG. 1B is set to the position C and switched to the second screen size. In addition, the same figure (B)
Shows a mode of the visual field frame switching mechanism when the visual field frame switching lever 8 is set to the H position to set the standard size of the first screen size. Further, FIG. 7C shows a mode of the visual field frame switching mechanism when the visual field frame switching lever 8 is set to the position P to set the third screen size. In each case, the leftmost drawing shows the side surface, the central drawing shows the front surface of the field frame switching piece, and the right end drawing shows the posture of the hole of the viewing frame piece from the front.

In the standard size state of FIG. 23 (B),
Cam followers 12 of the first and second swinging members 121 and 122
4, 125 are both cam lobes 120 of the field frame switching cam 120.
a, so that the rocking levers 126, 127 of both members 121, 122 withdraw against the biasing force of the click spring 129 to a position where the two 126, 127 overlap. As the swing levers 126 and 127 are retracted,
The first and second visual field frame pieces 106 and 107 are retracted out of the visual field, and the base plate 108 and the first visual field regulating window 111 of the left and right fixed frame pieces 109 and 110 are opened, so that the eyepiece window 10 is removed. The field of view seen corresponds to the first screen size H.

When the field frame switching lever 8 is switched to the position C from the set state of the standard first screen size H,
The movement of the visual field frame switching lever 8 is transmitted to the notch engaging portion 131 so that the visual field frame switching cam 120 is in the first direction.
3 rotates in the solid arrow r _a direction (B), as shown in FIG. 23 (A), only the cam followers 124 of the first swing member 121 is disengaged from the cam crest 120a of field frame switching cam 120, the first The swing lever 126 of the swing member 121 is the click spring 1.
It is rotated by the urging force of 29. This swing lever 126
With the returning operation of the first visual field frame piece 106, the first visual field frame piece 106 enters the visual field, the second visual field regulating window 112 overlaps the first visual field regulating window 111, and the visual field seen from the eyepiece window 10 is the second screen size C.
It corresponds to.

When the field frame switching lever 8 is switched to the position P from the set state of the first screen size H, the motion of the field frame switching lever 8 is transmitted to the notch engaging portion 131, and the field frame switching is performed. FIG. 23 in which the cam 120 is in the second direction.
Rotates in the broken arrow r _b direction (B), as shown in FIG. 23 (A), only the cam followers 125 of the second swing member 121 is disengaged from the cam crest 120a of field frame switching cam 120, the second
The swing lever 127 of the swing member 122 causes the click spring 12 to move.
It is rotated by the biasing force of 9. With the return operation of the swing lever 127, the second visual field frame piece 107 enters the visual field, the third visual field regulating window 113 overlaps the first visual field regulating window 111, and the visual field seen from the eyepiece window 10 is Third screen size P
It corresponds to.

[0101]

As described above, according to the present invention, in the viewfinder having the real image type finder optical system in which the objective optical system, the reversing optical system and the eyepiece optical system are arranged in that order, the real image plane and the real image are provided. Since the reversing optical system portion after the surface is movably held in parallel with the real image surface,
It is possible to adjust the pointing ratio without bias to the subject image on the lens surface, and yet to move the reversing optical system part with a much simpler structure than the objective optical system, so it is easy to realize. It is possible to obtain an instruction rate adjusting mechanism having excellent properties and a simple configuration.

According to the second aspect, the spring member for urging the reversing optical system portion in one direction, and the screw member retracting in the same direction as the urging direction of the spring member and advancing in the opposite direction are used to move the real image plane and thereafter. Since the reversing optical system part is held movably,
The reversing optical system portion correctly follows the movement of the screw member by the urging force of the spring, so that the instruction rate adjustment that requires a delicate operation can be accurately performed.

According to the third aspect of the invention, since the spring member is constituted by the leaf spring which can be interposed in the narrow portion, the space can be effectively utilized, which contributes to downsizing of the viewfinder and downsizing of the camera. Will be things.

According to the fourth aspect, since the switching field frame is held along the real image plane so as to be movable integrally with the reversing optical system portion after the real image plane, the field frame is displaced even after the instruction rate adjustment. Not only that, but also the screen size other than the standard screen size can be adjusted at the same time.

According to the fifth aspect, since the reversing optical system portion after the movable real image surface is constituted by the independent member, it is possible to prevent the eyepiece optical system from being affected after the instruction rate adjustment. .

[Brief description of drawings]

1A and 1B are external views of a camera incorporating a finder according to a first embodiment of the present invention, where FIG. 1A is a schematic perspective view seen from the front side, and FIG. 1B is a schematic perspective view seen from the back side. .

FIG. 2 is a schematic perspective view showing an assembled state of a finder optical system.

FIG. 3 is an exploded perspective view showing the overall structure of a finder.

FIG. 4 is a schematic cross-sectional view showing its assembled state.

FIG. 5 is a front view of the first lens and a portion related thereto when the objective optical system is incorporated in the finder case.

FIG. 6 shows a variable magnification cam member, (A) is an external perspective view,
(B) is a development view.

FIG. 7 is a diagram showing cam curves of first to third lens cams.

FIG. 8 is a perspective view schematically showing the arrangement of each member in the image inverting optical system.

FIG. 9 is a perspective view showing a specific configuration of a visual field frame switching mechanism.

FIG. 10 shows the movement of the cam member of the visual field switching mechanism,
FIG. 9A is a diagram schematically showing a second screen size state, FIG. 9B is a first screen size state, and FIG. 9C is a third screen size state.

FIG. 11 is a perspective view showing a mounting structure of an AF module to a finder.

FIG. 12 is an assembly cross-sectional view showing an example of a diopter adjustment mechanism that realizes focusing in the entire area including a telemacro area.

FIG. 13 is an assembled perspective view thereof.

FIG. 14 is an exploded perspective view showing first and second variable magnification cam members.

15 is a diagram schematically showing a film size that can be photographed by the camera shown in FIG.

FIG. 16 is an exploded perspective view showing the overall configuration of a finder according to a second embodiment of the present invention.

FIG. 17 is a schematic cross-sectional view showing its assembled state.

FIG. 18 is a perspective view schematically showing the configuration of an image inverting optical system.

FIG. 19 is a perspective view showing a mounting configuration of a field frame switching mechanism drive unit.

FIG. 20 is an exploded perspective view showing a mounting structure of a field frame piece of the field frame switching mechanism.

FIG. 21 is an exploded perspective view showing the configuration of a field frame switching mechanism drive unit.

FIG. 22 is a partially cutaway side view showing an assembled state of the field frame switching mechanism.

23A shows the operation of the view frame switching mechanism in the second screen size state, FIG. 23B shows the first screen size state, and FIG. 23C shows the operation of the view frame switching mechanism in the third screen size state. The front view of a switching piece and the front view of the hole of a visual field frame piece.

[Explanation of symbols]

1 Body 2 Shooting Zoom Lens 7 Zoom Operating Lever 8 Field Frame Switching Lever 11 Viewfinder Case 12 Porro Prism 12b ₂ Vertical Image Forming Surface 13 First Triangular Prism 14 Second Triangular Prism 19 First Lens Holder 19c Cam Follower 20 Second Lens Holder 20c cam follower 21 third lens holder 21c cam follower 22 first lens suspension shaft 23 second lens suspension shaft 26 first adjustment screw 27 variable magnification cam member 28 cam shaft 28a male screw 28b screw head 30 cam gear 32 tension spring 33 compression spring 40 covered Working part 41 Drive part 42 1st view frame piece 42b 1st arm 42c Cam follower 43 2nd view frame piece 43b 2nd arm 43c Cam follower 44 Spindle 45 Rotating shaft 46 1st cam piece 47 2nd cam piece 48 Manipulated arm 49 Cam member 50 Cam Energizing Spring 51 Field Frame Piece Energizing Spring 52 Field Frame Piece Energizing Spring 54a Mounting Pin 54b Mounting Pin 55a Pin Inserting Hole 55b Pin Inserting Long Hole 56a Support Bracket 56b Support Bracket 56c Support Bracket 57a Compression Spring 57b Compression Spring 57c Compression spring 58a screw 58b screw 58c screw 59 screw hole 60 first lens holder 60a cam follower 61 second lens holder 61a cam follower 62 lens suspension shaft 63 tension spring 64 first variable cam member 65 second variable cam member 66 cam shaft 67 coupling lever cam shaft 68a first diopter correction cam follower 68b second diopter correction cam follower 69 diopter correction cam shaft 70 diopter correction cam member 78 finder case 79 Porro prism 79b ₂ vertical image plane 80 triangular prism 81 Mira 84a 1st lens holder 84b 2nd lens holder 86 Lens suspension shaft 88a 1st cam follower 88b 2nd cam follower 89 Variable magnification cam member 90 Cam shaft 92 Extension spring 95 Cam position adjustment screw 96 Cam position adjustment compression spring 102 Prism position adjustment screw 103 leaf spring 104 drive unit 105 actuated unit 106 first
Field frame piece 107 Second field frame piece 109 Left fixed frame piece 110 Right fixed frame piece 114 Support point pin 117 Horizontal oblong hole 118 Inclined oblong hole 119 Swing switching mechanism 120 Field frame switching cam 120a Cam mountain 121 First
Swing member 122 Second swing member 124 Cam follower 125 Cam follower 126 Swing lever 127 Swing lever 128 Spindle 129 Click spring 130 Rotation axis A AF module AX Optical axis F1 Finder F2 Finder G1 First lens G2 Second lens G3 Second 3 lenses G4 4th lens G5 eyepiece lens Gi 1st lens Gj 2nd lens Ga 1st lens Gb 2nd lens Gc eyepiece H 1st screen size C 2nd screen size P 3rd screen size K camera

Claims (5)

[Claims] 1. In a finder including a real image type finder optical system in which an objective optical system, a reversing optical system and an eyepiece optical system are arranged in that order, a real image plane and a reversing optical system portion after the real image plane are the real image. A viewfinder pointing ratio adjusting mechanism characterized by being held so as to be movable parallel to the surface. 2. A mechanism for movably holding a reversing optical system portion after the real image plane, a spring member for urging the reversing optical system portion in one direction, and a retracting member in the same direction as the biasing direction of the spring member. The pointing rate adjusting mechanism for the finder according to claim 1, further comprising a screw member that moves in the opposite direction. 3. The indicator ratio adjusting mechanism for a finder according to claim 2, wherein the spring member is formed of a leaf spring. 4. The viewfinder according to claim 1, wherein a switching field frame is arranged along the real image plane, and the switching field frame is held so as to be movable integrally with a reversing optical system portion after the real image plane. Indicator rate adjustment mechanism. 5. The finder pointing ratio adjusting mechanism according to claim 1, wherein the reversing optical system portion after the movable real image surface is constituted by an independent member.