JP2003186083A - Camera finder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera finder of an inversed Galilean optical system in which the visual field range of the finder can be magnified steplessly according to the zooming of the camera. <P>SOLUTION: The camera finder has a constitution provided with the inversed Galilean optical system consisting of a finer window 11, a finer objective lens 23, a half mirror 24, and an eye piece 25, and a lighting optical system consisting of a lighting window 12, a field frame 26, and a reflecting mirror 27, magnifying lenses 13 and 14 made freely mobile by guide shafts 30a and 30b are provided in a lighting optical path between the reflecting mirror 27 and the half mirror 24. The positions of the magnifying lenses 13 and 14 are varied according to the zooming of the camera by a cam 20 and cam claws 34 and 35. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a daylighting type reverse Galileo type camera finder, and more particularly to a camera finder for continuously zooming the field of view of the finder according to the zooming of the camera. Pertain to.

[0002]

2. Description of the Related Art A lighting type reverse Galileo type finder is provided with a lighting window on the side of a finder window, and the light incident from the lighting window is passed through a field frame and then reflected by a reflection mirror. It is configured to lead to an inverse Galileo optical system. That is, in this finder, the subject image is taken by the reverse Galileo optical system, and the visual field range (shooting range) is taken by the daylighting optical system.
Can be observed through the eyepiece.

Many cameras having a zoom function are equipped with the above-mentioned reverse galileo finder.
Some are configured as muffiners. This
The mufinder is configured to change the image magnification of the finder by moving the finder objective lens back and forth in conjunction with zooming of the camera.

On the other hand, in this type of zoom finder,
There is a configuration in which the visual field range is switched to several stages (for example, three stages) according to the zooming of the camera. Specifically, three types of frames having different visual field ranges are provided as the visual field frame, one of these frames is selected corresponding to the zooming position of the camera to be the visual field frame, and the other frame is selected. The mu is covered up.

[0005]

In the case of the above zoom finder in which the finder objective lens is moved forward and backward to change the magnification, the image magnification can be changed steplessly. However, in order to increase the magnification, the objective lens is increased. Must be remarkably increased, and the aberration of the objective lens is increased, so that the lens performance is deteriorated and the resolution is deteriorated.

The zoom finder for switching the visual field range to several steps does not have a problem of resolution, but the visual field range is switched stepwise, so that the visual field range is not adapted to each zooming position of the camera.

In view of the above situation, it is an object of the present invention to provide a reverse-Galileo optical system camera finder capable of continuously changing the finder field range in accordance with the zooming of the camera.

[0008]

In order to achieve the above object, the present invention provides a camera finder configured to guide light incident from a daylighting window to an inverted Galilean optical system through a field frame.
In the above, at least one variable magnification lens disposed in the optical path of the light incident from the lighting window and movably provided in the optical axis direction of the light, and the above variable magnification lens are displaced in association with the zooming of the camera. Therefore, a camera finder is provided, which is provided with a zoom interlocking means for changing the field of view of the finder.

Further, the camera finder of the invention described above.
Can be configured to displace the field frame together with the zoom lens by the zoom interlocking means.

[0010]

In the camera finder constructed as described above, the zoom lens zooms in accordance with zooming of the camera, and the field of view is magnified by the light collected through the field frame. Further, even if the visual field frame and the variable magnification lens are displaced, the visual field range is similarly magnified. Since the viewfinder objective lens is not moved, it is not necessary to provide a large objective lens.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a simplified front view of a camera 10 equipped with a camera finder according to the present invention.

The finder of the camera 10 is a light-reversing reverse Galileo finder, and a finder window 11 and a daylighting window 12 are provided. Further, in this finder, variable magnification lenses 13 and 14 are arranged in the light collecting optical path, and the view field range (shooting range) of the finder is changed in size in association with zooming of the zoom lens unit 15. Has become.

Zoom lens unit 15 of camera 10
Is a drive barrel (for example, a cam barrel) 15b that rotates in the fixed barrel 15a, and a movable barrel 15 that is moved and driven by the drive barrel 15b to displace the taking lens 15c in the optical axis direction.
and d. The drive cylinder 15b is rotatably driven via a motor and a reduction gear (not shown), but is rotatably driven by a manual lever provided integrally with the drive cylinder 15b or interlocked with the drive cylinder 15b. Can be configured as.

A gear 1 is provided on the outer periphery of the rear end of the drive cylinder 15b.
5e is integrally provided, and an interlocking gear 16 meshed with the gear 15e operates a finder interlocking mechanism for displacing the variable power lenses 13 and 14.

That is, since the interlocking gear 16 drives the reduction gear 17, the cam 20 is driven via the bevel gears 18 and 19.
Is rotated, and by this cam 20, the variable magnification lenses 13 and 14 are
Moves. The camera 10 has a finder window 1
1, various members such as the flash emission window 21 and the shutter button 22 are assembled in addition to the daylighting window 12, but these members are omitted.

FIG. 2 is a partially enlarged sectional view showing the internal structure of the finder by cutting the camera 10 along the line AA in FIG. 1, and FIG. 3 is an exploded view showing the optical system of the finder. It is a perspective view.

As shown in the figure, the viewfinder includes a viewfinder objective lens (concave surface) 23, a half mirror 24,
An inverse Galileo optical system including an eyepiece lens 25 is provided, and the subject image light Pa incident from the finder window 11 is guided to the eyepiece through the inverse Galileo optical system.
A prism may be provided instead of the half mirror 24.

A daylighting window 1 is provided with a daylighting optical system including a field frame 26, a reflection mirror 27, and variable power lenses 13 and 14.
The daylighting light Pb incident from 2 is guided through the daylighting optical system to the half-mirror 24 of the inverse Galileo optical system, reflected by the half-mirror 24 and guided to the eyepiece. As shown in FIG. 3, the visual field frame 26 is an opaque plate-shaped body, and an index 26a indicating a photographing range is formed on the plate surface as a transparent portion.

On the other hand, the variable power lenses 13 and 14 are arranged between the half mirror 24 and the reflection mirror 27 so that the magnification is varied on the light collecting optical axis between the mirrors 24 and 27. is there. Specifically, the supporting portion (for example, lens frame) 28 of the variable power lens 13 has hollow guide portions 29 on both sides thereof.
a and 29b are provided, and these guide portions 29a and 29b slide on guide shafts 30a and 30b penetrating the inside.

Similarly, the variable power lens 14 has hollow guide portions 32 on both sides of a support portion (for example, a lens frame) 31 thereof.
It has a and 32b, and slides the guide shafts 30a and 30b which penetrate these guide parts 32a and 32b. The guide shafts 30a and 30b are provided at positions outside the daylight between the mirrors 24 and 27, and
Finder base 3 so that it is parallel to the optical axis of daylight
It is fixed to 3.

A cam claw 34 is provided on the guide portion 29a of the variable power lens 13, and the cam claw 34 is brought into contact with the cam portion 20a. Similarly, a cam claw 35 is attached to the guide portion 32a of the variable power lens 14. The cam pawl 35 is provided in contact with the cam portion 20b of the cam 20. The variable power lenses 13 and 14
Between the guide portions 29a and 32a of the
coil springs 36a and 37a for expanding the pressure between b and 32b
And the guide portions 29a, 2 of the variable power lens 13
9b and the finder base 33 are provided with coil springs 36b, 37b for expanding the pressure, and the cam pawls 34, 35 are provided.
The pressing force is applied to.

The cam 20 is a round bar-shaped cam provided with cam portions 20a and 20b, is rotatably supported by the finder base 33, and a bevel gear 19 is provided at one end thereof. The bevel gear 19 meshes with the bevel gear 18 that rotates coaxially with the reduction gear 17, and the cam 20 is rotated by being rotationally driven according to the zooming of the zoom lens unit 15.

The finder constructed as described above observes the object image formed by the inverse Galileo optical system and the index 26a of the photographing range formed by the daylighting optical system by looking into the eyepiece lens 25. You can

Then, the zoom lens unit 15 is zoomed.
When geared, interlocking gear 16, reduction gear 17, bevel gear 1
Since the cam 20 is rotated via the interlocking path of 8 and 19, the cam claws 34 and 35 move the variable power lenses 13 and 14 following the cam portions 20a and 20b.

Therefore, the image formation state of the daylight passing through the field frame 26 changes according to the moving position of the variable power lenses 13 and 14. As a result, by zooming the zoom lens unit 15 to the wide side, the variable power lenses 13 and 14 can be obtained.
Is displaced as shown in FIG. 4, and the index 26a is as shown in FIG.
When the zooming is performed so as to expand the field of view, and when the zooming is performed to the tele side, on the contrary, the zooming lenses 13 and 14 are used.
As shown in FIG. 7, the index 26a is scaled so as to reduce the visual field range.

FIG. 8 is an enlarged sectional view of a finder portion similar to FIG. 2 showing another embodiment. This embodiment is characterized in that a field frame 26 is provided in place of the variable power lens 13, and the other configurations are the same as those of the finder shown in FIG.

In the finder of this embodiment, the field frame 26 moves together with the variable power lens 14 as the zoom lens unit 15 zooms. As a result, the field frame 26
Since the zoom lens 14 and the zoom lens 14 are displaced as shown in FIG. 9 in wide zooming and as shown in FIG. 10 in telescopic zooming, the index 26a of the field frame 26 becomes the finder of FIG. It is also scaled.

Although the embodiments of the present invention have been described above, the number of variable power lenses can be arbitrarily increased or decreased, and the variable power lenses and the field frame are not limited to the cam mechanism, and the screw feed of the screw screw is used. It can be moved by a mechanism. Further, the finder interlocking means for interlocking the finder and the zoom lens unit by the gear interlocking structure including the bevel gear has been described, but the finder interlocking means is not limited to this embodiment and may be configured by other known means. You can

[0029]

As described above, the finder of the present invention
Has a configuration in which the zoom lens disposed in the light collecting optical path, or the field frame and the zoom lens are displaced in conjunction with the zooming of the camera, so that the viewfinder field of view is adjusted to the zooming of the camera. Thus, it becomes a finder of an inverse Galileo optical system capable of zooming infinitely.

[Brief description of drawings]

FIG. 1 is a simplified front view of a camera showing an embodiment of a finder according to the present invention.

FIG. 2 is a partial enlarged cross-sectional view showing an internal structure of a finder taken along the line AA of the camera shown in FIG.

FIG. 3 is a diagram showing a viewfinder-optical system of the camera shown in FIG.

FIG. 4 is an explanatory diagram showing an operating state of a variable power lens that is displaced by zooming on the wide side of the camera shown in FIG.

FIG. 5 is an explanatory diagram similar to FIG. 4, showing an operating state of a variable power lens that is displaced by zooming on the tele side.

FIG. 6 is a simplified diagram showing a viewfinder field range which has been magnified by zooming on the wide side of the camera shown in FIG.

FIG. 7 is a simplified diagram similar to FIG. 6, showing a viewfinder field range that has been magnified by zooming on the tele side.

FIG. 8 is an enlarged sectional view similar to FIG. 2, showing another embodiment of the present invention.

9 is an explanatory diagram showing a zooming operation of the view field frame of the viewfinder shown in FIG. 8 and a zoom lens toward the wide side.

FIG. 10 is an explanatory view similar to FIG. 9 showing a zooming operation of the field frame and the variable power lens toward the tele side.

[Explanation of symbols]

10 cameras 11 Finder window 12 daylighting windows 13, 14 Variable magnification lens 15 zoom lens unit 20 cams 23 Finder-Objective lens 24 Harm mirror 25 eyepiece 26 view frame 26a index 27 Reflection mirror 29a, 29b, 32a, 32b Guide part 30a, 30b Guide shaft 34, 35 cam claw

Claims (2)

[Claims] 1. In a camera finder configured to guide light entering from a daylighting window to a reverse Galileo optical system through a field frame, the camera finder is arranged in an optical path of light entering from the daylighting window and is movable in an optical axis direction of the light. At least one variable magnification lens provided, and a zoom interlocking means for varying the zoom range of the above-mentioned variable magnification lens in association with zooming of the camera to change the magnification of the field of view of the field of view. Camera finder. 2. The camera finder according to claim 1.
2. A camera finder characterized in that the field of view frame is displaced together with the variable power lens by the zoom interlocking means.