JPS62284336A - Finder device for lens shutter type camera having macrophotographing function - Google Patents

Abstract

PURPOSE:To reduce a parallax at the time of macrophotographing by allowing an optical element for correcting the parallax to advance into a finder optical system at the time of macrophotographing by bending a finder optical axis in the optical axis direction of a photographic optical system. CONSTITUTION:When a cam ring 14 is driven by a zooming motor, and from the macrofeeding-out section 20f of its zooming cam groove 20, a macroend fixing section 20g is engaged to the roller of a front group frame, the front group frame is further fed out of a telephote end and goes into a macrophotographing area. In such case, as for a cam plate 53, a subdriving pin 70 of a deflection angle prism operating plate 67 is engaged and moved from the projecting motion section of its parallax correcting cam groove to a projecting position fixing section. As a result, the deflection angle prism operating plate 67 is operated, and a deflection angle prism P1 is turned in an optical path by the force of a torsion spring 75. Therefore, the parallax at the time of macrophotographing can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION 3. Detailed Description of the Invention "Technical Field" The present invention relates to a lens shutter type camera having a macro photography function, and particularly to a finder device thereof.

"Prior art and its problems" One of the problems with lens-shutter cameras compared to single-lens reflex cameras is the field of view due to the finder optical system and the shooting screen due to the photographic optical system. In other words, parallax exists. In particular, this parallax becomes large when macro photography is enabled by moving the photographic optical system further forward than the range that can normally be photographed. For this reason, in the past, a field frame for macro photography was drawn separately in the viewfinder, and it was undeniable that the usability was poor.

``Object of the Invention'' The present invention is directed to a lens-shutter camera capable of macro photography, and particularly to reduce parallax as much as possible during macro photography.

"Summary of the Invention" The present invention provides a viewfinder optical system that moves into the viewfinder optical system in conjunction with the transition of the photographing optical system to the macro photographing range, and that the viewfinder optical axis is set as the optical axis of the photographing light '#- system. It is characterized by the provision of an optical element that corrects parallax by bending in the direction.

"Embodiments of the Invention" The present invention will be described below with reference to illustrated embodiments. In this embodiment, the present invention is applied to a lens-shutter type camera equipped with a zoom lens function and a macro photography function.

This lens-shutter camera consists of a lens barrel block 1 for a zoom lens, a finder and a strobe block (hereinafter simply referred to as the finder block) 2) a distance measuring device, as shown schematically in Figure 1. (AF device) includes a light emitting section 3, a light receiving section 4, and a zoom motor 5 for zooming. These elements are attached to the base plate 6, which is the fixed part of the camera body.
(See Figures 14 to M16).

That is, the base plate 6 is a lens barrel support plate portion 6 that is perpendicular to the optical axis.
a, and the upper end P8 of this lens barrel support plate portion 6a. It has a horizontal support plate part 6b bent at a right angle and a motor support plate part 6c perpendicular to the horizontal support plate part 6b, and the lens barrel support plate part 6 is supported by the lens barrel block. It's been done. Further, a zoom motor 5 located at the upper center of the lens barrel block 1 is fixed to the motor support plate portion 6c.
A light emitting section 3 and a light receiving section 4 fixed to the horizontal support plate section 6b are located on both sides of the horizontal supporting plate section 6b. The finder block 2 is fixed to the front right side of the horizontal support plate portion 6b. 6e is a carriage support plate fixed to the motor support plate portion 6C via a spacer 6f.

lens barrel block] is driven by a zoom motor 5. The structure of the lens barrel block 1 will be explained with reference to FIGS. 11 to 16. A rear fixing plate 1] is fixed to the lens barrel support plate portion 6a of the base plate 6 via fixing screws 10. Four guide rods 12 are fixed to the rear fixing plate 11 and are located around the optical axis in parallel with the optical axis, and a front fixing plate 13 is fixed to the tip of the guide rods 12. The above are the main fixing elements of the lens barrel block 1.

A cam ring 14 is located between the rear fixing plate 11 and the front fixing plate 13.
is rotatably supported, and a gear 15 that engages with the cam ring 7 either directly or through a crooked line is fixed to the outer periphery of the cam ring 14 by a fixing screw 15a (FIG. 12). This gear] 5 may be a sector gear that covers the rotation range of the cam ring 14. The cam ring 14 has zooming cam grooves 20, 21 for the front group and the rear group.

FIG. 13 is a developed view of the zooming cam grooves 2o and 21, and the zooming cam groove 21 for the rear group has a wide-angle end fixed section 21a,
It has a variable power section 21b and a fixed telephoto end section 21c%.

On the other hand, the zooming cam groove 20 for the front group includes an opening/closing section 20a of the barrier block 30, a lens storage section 2ob,
It has a wide-angle end fixed section 20c, a transformation section 20d, a telephoto end fixed section 20e, a macro feeding section 20f, and a macro fixed section 209. The rotation angle of each of these sections is
The total angle θ1 of the barrier opening/closing section 20a of the zooming cam groove 20, the lens storage section 20b, and the wide-angle end fixing section 20c, or the wide-angle end fixing section 21 of the zooming cam groove 21.
The angle θ1 of the magnification variable section M20d and the magnification variable section 21b are the same, and the angle θ2 of the variable magnification section M20d and the variable magnification section 21b are the same, and the angle θ2 of the variable magnification section M20d is the same as that of the telephoto end fixed section 20e.
, macro feeding section 2Of, and macro fixed section 209
The total angle θ3 is the same as the angle θ3 of the telephoto end fixed section 21c. The barrier block 30 rotates between the pair of barriers 31 by rotating the barrier opening/closing section 20a of the cam ring 14.
It opens and closes.

This zooming cam groove 20 and zooming cam groove 2]
The front group frame 16 is movably fitted to the guide rod 12.
The roller 17 of the rear group frame 18 and the roller 19 of the rear group frame 18 are fitted.

A decorative frame 22 is fixed to the front group frame 16 via fixing screws 22a, and roughly a shutter block 23 is also fixed to the front group frame 16. The front group lens frame 24 holding the front group lens 1 is screwed together with the shutter block 23 by a helicoid 25, and has an arm 24at that engages with a lens extension lever 23a of the shutter block 23. Therefore, when the lens advancing lever 23a rotates in the circumferential direction and the front group lens frame 24 rotates accordingly, the front group lens frame 24 moves along the helicoid 25 in the optical axis direction. The rear group lens L2 is directly fixed to the rear group frame 18.

The shirt tab block 23 itself is well known. The built-in pulse motor generates an angle corresponding to the distance measurement signal from the distance measurement device having the light emitting section 3 and the light receiving section 4. 23b is opened for a predetermined time and then closed again, and then the lens feeding lever 23a7Fr is returned to its original position.

The finder 70 to 2 includes a finder device M8 and a strobe device 9. Both the finder device 8 and the strobe device 9 change the viewfinder field of view and change the illumination angle (light intensity) of the strobe in conjunction with changes in the focal length of the lens barrel block 1. The power source for this purpose is the zoom morph 5 mentioned above. A pinion 50, which is different from the above-mentioned pinion 7, is engaged with the screw 15 of the cam ring 14, and the shaft 5 of the pinion 5o is extended to the rear of the base plate 6, and has a deceleration screw row 52 at its rear end.
Or is provided. The final gear 52a of the reduction gear chain 52 is engaged with the rack 53a of the cam plate 53. The cam plate 53 can vibrate in the left-right direction, and has a downwardly bent portion 5 at the rear end.
31), a rack 53a is integrally provided at the tip (lower end) thereof. The reduction gear train 52 reduces the rotation of the gear 15,
This reduces the movement of the cam 1 tongue 14 and applies it to the cam plate 53. The cam plate 53 is provided with a variable power cam groove 55 for the finder device 8, a balaxe correction cam groove 56, and a strobe cam groove 57 for the strobe device 9.

The lens system of the finder M8 basically consists of a fixed subject-side lens group L3, an eyepiece lens L4, a movable variable magnification lens L5, and a deflection prism P for macro photography. ]. Variable magnification lens group L5
The angle-deflection prism P1 advances onto the optical axis only during macro photography and particularly corrects balax. In other words, as mentioned above, in a lens-shutter camera, vararax is unavoidable, and the amount of vararax increases the closer you shoot, but the camera of the present invention is capable of macro photography, and at this time, the amount of vararax increases. Therefore, only during macro photography, a wedge-shaped deflection prism P1 that is thick at the bottom and thin at the top is inserted into the optical path to bend the optical path downward so that a portion closer to the photographed area can be observed. FIG. 4 schematically shows the optical path when the deflection prism P1% is inserted.

The present invention is also characterized by the insertion of the deflection prism P1. In other words, the deflection prism P1 advances and retreats into the finder optical path between the fixed subject-side lens group L3 and the eyepiece lens group L4, without changing (increasing) the length of the entire finder device in the optical axis direction. ,
Parallax correction can be performed during macro photography.

In addition, the strobe device 9 narrows down the irradiation angle as the focal length of the photographing lens becomes longer, that is, as the lens extends.
During macro photography, the illumination angle 18 is widened to reduce the amount of light to the subject. Therefore, in this embodiment, the Fresnel lens L6jt is fixed, and the reflective shade 59 holding the xenon lamp 58 is moved in the optical axis direction.

1 to 10 show specific structures for giving the finder device 8 and strobe device 9 the above-described movements. A finder main plate 60 is fixed on the finder block 54 fixed to the base plate 6, and a guide bin 62 that fits into the linear guide groove 61 of the cam plate 53 is fixed to this finder main plate 6o. The cam plate 53 is slidable by the linear guide groove 6], the guide bin 62, and a restraining guide 60a formed as a cut-and-raised piece on the finder main plate 60, which suppresses the floating of the front of the cam plate 53. The direction is restricted to the left and right (Figures 6 and 7).

The finder main plate 60 has a variable magnification lens guide groove 63, a declination prism guide groove 64, and a strobe guide groove 65 cut in the front-rear direction. The guide protrusion 66a of the variable magnification lens frame 66 is fitted into the deflection prism guide groove 64, the guide protrusion 67a of the deflection prism actuating plate 67 is fitted into the deflection prism guide groove 64, and the reflector 59 is fixed to the strobe guide groove 65. A guide protrusion 68a of the strobe case 68 is fitted to restrict the moving direction of these elements in the forward and backward directions. In each of the guide projections 66a, 67a, and 68a, driven pins 69, 70, and 71 are installed. and is fitted into the strobe cam groove 57. Therefore, when the cam plate 53 moves left and right, the variable magnification lens frame 66, deflection prism operating plate 67, and strobe case 68 move back and forth, respectively, with the shapes of these cam grooves 55, 56, and 57. becomes.

Each section of the variable power cam groove 55, the balax correction cam groove 56, and the strobe cam groove 57 corresponds to each section described next for the zooming cam groove 20, 21 of the cam ring 14 in FIG.

That is, the variable magnification cam groove 55 has a wide-angle end fixed section 55a, a variable magnification section 55b, and a telephoto end fixed section groove 55C%, and the angles θ1, θ2) and θ3 of each of these sections are 13th
Diagrams and correspondences are provided.

On the other hand, the vararax correction cam groove 56 has a non-protruding section 56a, a protruding movement section (Mauro feeding section) 56b, and a protruding position fixed section (mouth end fixed section) 56a%. The strobe cam groove 57 includes a wide-angle end fixed section 57a, a variable power section 57b, a telephoto end fixed section 57c, and a macro feed 7 closed section 57d.
, and a macro end fixed section of 57e%. The variable magnification section 57b of the strobe cam groove 57 is a section where the xenon lamp 58 is brought into contact with the Fresnel lens L6, and as the contact occurs, the range of the irradiation angle of light emitted from the Fresnel lens L6 is narrowed, and the focal length is increased. This has the effect of substantially increasing the guide number. On the other hand, at the macro edge section gate 57d, the irradiation angle is widened, and the guide number for macro photography is substantially reduced.

The variable magnification lens frame 66 supporting the variable magnification lens detail L5% is the first
As shown in FIG. 0, the guide surface 4a of the finder block 54 is movably supported in a suspended manner. When the variable magnification cam groove 55 is moved, the magnification of the finder optical system including the subject side lens detail L3, the eyepiece lens group 4, and the variable magnification lens group 5 changes, and the photographing range by the boundary block 1 changes. , the field of view of the finder, etc. is quite poor.Such an optical system can be obtained with simple lens design techniques.

Next, the deflection angle actuation plate 67 will be explained mainly with reference to FIGS. 2 to 4. First, the deflection prism Pit made of synthetic resin is rotatably supported by the finder block 54 at fulcrums 74 at both lower ends thereof. A biasing torsion spring 75 is rotated around the fulcrum pin 74, and one end of this torsion spring 75 is connected to the deflection prism P1.
(The hook is stopped by the fixed position regulating piece 76,
The deflection prism P1% is always biased so as to be located within the optical path of the object side lens group 3 to variable magnification lens group L5. The position regulating piece 76 is located within an arcuate escape groove 79 formed in the finder block 54. The deflection prism operating plate 67 is sandwiched between the finder block 54 and a guide plate 80 fixed thereto, and the guide bin 81 installed on the side surface of the finder optical system 54
It fits into a straight guide groove 82 formed in .

The hypothetical restriction piece 76 can engage with a rotation blocking surface 77 and a rotation surface 78 of the deflection prism operating plate 67 . When the deflection angle prism 1 nosm actuating plate 67 is in the non-protruding section 56a of the driven pin 70 or the vararax correction cam groove 56, the rotation group stop face 77 is brought into contact with the regulating piece 76, and the torsion spring is activated. 75 and retreats from the optical path of the deflection prism Pi%, or when the driven bottle 70 reaches the protruding movement section 561), the rotating surface 78 is brought into correspondence with the hypothetical restriction piece 76.

Then, due to the force of the torsion spring 75, the deflection prism P1 rotates into the optical path, and its position regulating piece 76 moves toward the rotation surface 7.
8, it gradually protrudes into the optical path as shown in FIGS. 3 and 4, bends the finder optical path as shown in the figures, and brings the object below into the field of view.

That is, in this finder device having the above configuration, the cam 1 nong 14 is driven by the zooming motor 5, and the macro mouth end fixing section 209 is moved from the macro feeding section 2Of of the zooming cam groove 20 to the roller] 7 of the front group frame 6. When engaged, the front group frame 16 (front group lens Ll) is roughly extended from the telephoto end and enters the macro photography area. At this time, the cam plate 5
3 is the protruding movement section of the vararax correction cam groove 56 (
The driven pin 7o of the deflection prism actuating plate 67 is engaged with the protruding position fixing section (macro mouth end fixing section) 56c from the macro feed section) 56b. Therefore, as described above, the declination angle block 1
The nosm P1 advances into the finder optical axis and bends the finder optical axis toward the optical axis side of the photographic lens to reduce parallax.

"Effects of the Invention" As described above, the present invention has a structure in which an optical element for correcting parallax is inserted into the finder optical system during macro photography by bending the finder optical axis in the direction of the optical axis of the photographing optical system. Therefore, it is possible to secure a small parallax field of view without drawing a field frame for macro photography in the finder, and it is possible to provide an excellent usability.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of the Fig. device of a lens-shutter camera having a macro photography function according to the present invention, and FIGS. Figure 4 is a cross-sectional view of the deflection prism in its state of entering the optical path, and Figure 5 is the deflection prism inside the optical axis of the finder. Indicates the state in which the V
' On line v-v in Figures 3 and 4; Figure 8 is a sectional view;
The figure is a cross-sectional view taken along the line ■-■ of Figure 6, Figure 8 is a rear view of Figure 6, Figure 9 is a plan view of Figure 6 with the cam plate and finder main plate removed, and Figure 10 is a sectional view taken along the line x-X in Figure 6, Figure 11 is an exploded perspective view of the zoom lens barrel, Figure 12 is a longitudinal sectional view of the same, and Figure 13 is an exploded view of the cam ring. 14 is a front view of the second plate portion fixed to the camera body, FIG. 15 is a sectional view taken along the line xv-xv in FIG. 14, and FIG. 16 is a plan view of FIG. 14. Pl... Deflection prism (optical element), ]... Lens barrel block, 2... Finder and strobe block 5
...Zoom motor, 8...Finder device, 14.
...Cam ring, 20.21...zooming cam groove,
2Of...Macro feeding section, 20e...Macro mouth end fixed section, 16...Front group frame, 24...Front group lens frame,
53... Cam plate, 56... Parallax correction cam groove, 56b... Projection movement section (macro feeding section), 56
c...Protrusion position fixed section (mouth end fixed section) 64.
... Deviation prism guide groove, 67... Deviation prism operating plate, 67a... Guide protrusion, 70... Driven bottle,
76...Position regulation piece. Patent applicant Kakoji Kogyo Co., Ltd.) -61+62→03 awn Figure 13 Figure 15 Figure 16

Claims (2)

[Claims] (1) In a lens-shutter camera having a macro photographing function, which includes a photographing optical system having a macro photographing function and a finder optical system consisting of an optical system separate from the photographing optical system, the finder optical system includes: An optical element is provided that moves into the finder optical system in conjunction with the transition of the photographing optical system to the macro photographing area and corrects parallax by bending the finder optical axis in the direction of the optical axis of the photographing optical system. A finder device for a lens-shutter camera that features a macro photography function. (2) In claim 1, the optical element for correcting parallax moves forward and backward within the finder optical system between a fixed subject-side lens group and an eyepiece lens group. A finder device for a lens-shutter camera with functions.