JPH06160943A - Finder device - Google Patents

Abstract

PURPOSE:To provide a finder device in which dirt or dust is prevented from infiltrating in the vicinity of the image-formation surface of an objective lens. CONSTITUTION:In this finder device, a finder visual field frame can be switched to the visual field frame 3a of an ordinary photographing state and the visual field frame of a panoramic state by interlocking with operation for switching the exposure range of film to the ordinary photographing range and the photographing range of a panoramic size; the device is provided with a real image type finder optical system by which an object image is formed on an image-formation surface 3 and guided to an ocular 6, a panoramic visual field mask 7 which is positioned in an optical path different from the optical path of the real image type finder optical system and where a luminous flux equivalent to the visual field frame of the panoramic state is transmitted through U-shaped holes 7a and 7b by moving a light shielding plate 8 when the exposure range is switched to the photographing range of the panoramic size, and a half mirror 5 by which the luminous flux transmitted through the mask 7 is synthesized to the visual field frame 3a of the ordinary photographing state and allowed to enter the ocular 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a finder device, and more particularly, to a finder device capable of switching a viewfinder field frame according to a photographing range of a normal size and a size different from the normal size.

[0002]

2. Description of the Related Art Various finder devices have been proposed in the past, which can switch the finder field frame in accordance with a photographing range of a normal size and a size different from that. For example, Japanese Patent Application No. 3-249400 discloses the same. An example is described.
The viewfinder device described in this document has a variable viewfinder optical system, and the viewfinder frame provided on the viewfinder image plane has a vertical dimension when the shooting screen is switched from full size to panoramic size. It has a short and changing mechanism that changes the dimension in the lateral direction to long,
Further, the Porro prism of the finder optical system is provided with parallax correction marks corresponding to the field frame for the full size screen and the field frame for the panoramic size screen and displayed without being mixed.

[0003]

However, in the one disclosed in the above-mentioned Japanese Patent Application No. 3-249400, the vicinity of the image plane of the objective lens having the field frame is magnified by the eyepiece. However, there is a problem that it may become conspicuous when there is dust or the like.

The present invention has been made in view of the above problems, and an object thereof is to provide a finder device in which dust and dirt do not enter the vicinity of the image plane of the objective lens.

[0005]

In order to achieve the above object, the finder apparatus according to the present invention operates to switch a photographing mask for defining an exposure range of a film between a normal photographing range and a photographing range of a different size. In a viewfinder device in which the viewfinder frame can be switched between the first viewfinder frame for the normal shooting range and the second viewfinder frame for the shooting range of a different size in conjunction with the Of a real-image finder optical system that forms an image on the image-forming surface that defines the field of view of the finder and guides the image to the eyepiece lens, and the exposure range that is located in an optical path different from the optical path of this real-image finder optical system. A light flux regulating means for transmitting a light flux corresponding to the second viewfinder field frame when switching to a shooting range of a size different from the range; The light beam transmitted through the light beam defining means are combined to the first finder field frame, characterized by comprising a beam combining means for incident on the eyepiece.

[0006]

A real image type finder optical system forms a subject image on at least an image forming surface that defines a viewfinder field for normal photographing, guides the image to an eyepiece lens, and an exposure range having a size different from that of the normal photographing range. When switched to the range, the light flux defining means transmits the light flux corresponding to the second finder field frame, and the light flux synthesizing means synthesizes the light flux passing through the light flux defining means into the first finder field frame to form the eyepiece. Let the light enter the lens.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. The image of the subject is formed through the objective lens 2 on the image forming surface 3 provided with a field mask 3a which is a first finder field frame.
Image on. This image is reflected downward by the first reflecting surface 4a of the Porro prism 4 behind the image plane 3 and further passes through the second reflecting surface 4b and the third reflecting surface 4c to the fourth reflecting surface of the Porro prism 4. A half mirror 5 which is a light beam synthesizing means obliquely installed at a place corresponding to the surface reflects the light backward and observes it through an eyepiece lens 6 as an erect image. That is, the finder optical system of the first embodiment is a real image type finder optical system configured as described above.

In front of the half mirror 5, a panoramic visual field mask 7 which is an opening member which constitutes a light flux regulating means is arranged in parallel with the image forming surface, and which is also a light shielding means which constitutes a light flux regulating means. A plate 8 is supported by a support rod 9 so as to be able to move in and out of the visual field mask 7. This panoramic field mask 7 has an elongated U-shaped hole 7a showing the range of the field of view at the time of panorama corresponding to the second finder field frame.
7b is provided, and the light taken in through the outside light intake window (not shown) is transmitted through the U-shaped holes 7a and 7b to send the light flux of the panoramic field shape to the half mirror 5. The light-shielding plate 8 is a rectangular plate member having a size sufficient to cover the U-shaped holes 7a and 7b of the panoramic field-of-view mask 7, and when the panorama photographing means is operated to switch to the panoramic photographing state. The support bar 9 allows the panoramic field mask 7 to be retracted. Further, when the panorama switching means is operated to enter the normal photographing state, the light shielding plate 8 is located at a position for blocking the light transmitted through the panoramic field mask 7.

The light beam of the panoramic field shape which has passed through the panoramic field mask 7 passes through the half mirror 5 and is observed together with the subject image incident from the objective lens 2 through the eyepiece lens 6. That is, the display of the panoramic field of view and the subject image from the objective lens 2 are simultaneously observed in an overlapping manner. Further, when the light shielding plate 8 is located at a position that blocks the light transmitted through the panoramic view mask 7, the display of the panoramic view does not appear in the view.

According to the first embodiment constructed as described above, since it is not necessary to insert a switching member in the image forming surface of the eyepiece optical system, the vicinity of the image forming surface can be hermetically sealed, and the change occurs. It is possible to provide a viewfinder device that does not deteriorate the field of view due to dust and fluff. Further, since the panoramic field-of-view mask switching mechanism is arranged apart from the finder optical system, there is an advantage that the degree of freedom in design can be taken, and the size and cost can be reduced.

FIG. 2 shows a second embodiment of the present invention. The subject image incident through the objective lens (not shown) is once reflected by the reflecting surface 11a of the first prism 11 and then formed on the image forming surface 11b. The image is reflected upward by the half mirror 12 which is a light beam combining means obliquely provided on the side of the first prism 11 and is reflected by the first reflecting surface 13a and the second reflecting surface 13b of the second prism 13. After that, it is observed through the eyepiece lens 14. That is, the finder optical system of the second embodiment is also a real image type finder optical system configured as described above.

The image plane 11b is provided with a visual field frame 11c which is a first viewfinder visual field frame showing a normal visual field range, and if necessary, a mark 11d etc. showing a panoramic visual field range. Is provided.

Below the half mirror 12, a panoramic field-of-view mask 15 which is a light flux defining means is arranged, and this panoramic field-of-view mask 15 indicates a range of a field of view during panorama corresponding to the second viewfinder field frame. Elongated U-shaped holes 15a and 15b are provided. The panoramic field mask 15 is provided at the same optical position as the image forming surface 11b when viewed from the eyepiece lens 14.

A light source 16 is arranged below the panoramic field mask 15. The light source 16 is provided so as to illuminate the panoramic visual field mask 15, and is composed of an LED or the like. In this configuration, when the normal photographing state is switched to the panoramic photographing state by the panorama switching means (not shown), the light source 15 is turned on.

The light flux of the light source that has passed through the U-shaped holes 15a and 15b of the panoramic field mask 15 passes through the half mirror 12 and the object image from the objective lens, and the second light flux.
The light is reflected by the first reflecting surface 13a and the second reflecting surface 13b of the prism 13 and is observed through the eyepiece lens 14. That is, the display of the panoramic field of view and the subject image from the objective lens are simultaneously observed in an overlapping manner.

In order to reduce power consumption, the light source 16 is turned on when the release button is half-pressed after switching to the panoramic shooting state to notify the photographer of the switching to the panoramic shooting state. It may be configured as follows. In this case, it is desirable that a simple mark 11d indicating the panoramic field of view be provided on the image forming surface 11b to facilitate framing.

The operation and effect of the second embodiment thus constructed is almost the same as that of the first embodiment.

FIG. 3 shows a third embodiment of the present invention. The subject image incident from the objective lens 21 is reflected by the two reflecting surfaces 22a and 22b of the first prism 22, and then formed on the image forming surface 22c provided with the field frame 22e which is the first finder field frame. . This image is observed through the eyepiece lens 25 after being reflected by the half mirror 23 which is a light flux synthesizing means and the reflecting surface 24 a of the second prism 24. That is, the finder optical system of the third embodiment is also a real image type finder optical system configured as described above.

On the other hand, on the opposite side of the second prism 24 of the half mirror 23, a mirror 27 is obliquely provided with a panoramic field mask 26, which is a light flux defining means provided substantially parallel to the photographing optical axis, interposed therebetween. The mirror 27 is rotatable around the support shaft 27a. An external light intake window 28 is provided in front of the mirror 27.
The panoramic field mask 26 is provided with elongated U-shaped holes 26a and 26b which indicate the range of the field of view at the time of panorama corresponding to the second viewfinder field frame.

The light beam incident from the outside light intake window 28 is reflected by the mirror 27, then passes through the U-shaped holes 26a and 26b of the panoramic field mask 26, passes through the half mirror 23, and passes through the objective lens 21. The light beam is overlapped with the other light flux, reflected by the second prism 24, and overlapped with the subject image by the eyepiece lens 25 for observation as a panoramic view display.

By operating a panorama switching means (not shown),
When the panoramic shooting state is switched to the normal shooting state, the mirror 27 causes the panoramic field of view mask 2 to center around the support shaft 27a.
It is designed to rotate until it comes into contact with 6. As a result, the external light incident through the external light intake window 28 is not reflected by the panoramic visual field mask 26, and the panoramic visual field range is not observed from the eyepiece lens 25.

The thus constructed third embodiment has substantially the same effects as the above-mentioned first and second embodiments.

FIG. 4 shows a fourth embodiment of the present invention. The fourth embodiment differs from the first embodiment only in the structure of the panoramic field mask and the switching means thereof, and the other parts have substantially the same structure, so that the members having the same function are the same. The reference numerals are given and the description thereof is omitted. As shown in FIG. 5, the panoramic field-of-view mask 31 of the fourth embodiment comprises an upper light-shielding mask 32 and a lower light-shielding mask 33, each of which has elongated U-shaped holes 32a and 3a.
3a is provided, and an elongated hole 32b,
33b are respectively bored and engaged with pins 35a and 35b protruding from a camera body (not shown) so as to be vertically slidable.

With such a structure, as shown in FIG. 5A, when the upper light-shielding mask 32 and the lower light-shielding mask 33 are located at the positions most apart from each other, the U-shaped hole 3 is formed.
The field of view in the normal photographing state is shown by the light transmitted through 2a and 33a, while it slides along the long holes 32b and 33b while engaging with the pins 35a and 35b, and is in the position closest to each other. At this time, as shown in FIG.
The field of view in the panoramic shooting state is shown.

Thus, according to the switching operation of the panorama switching means (not shown), the upper and lower light-shielding masks 32 and 33 are moved up and down to switch the relative positions of the U-shaped holes 32a and 33a. 6
The image showing the visual field range interlocked with the switching transmitted through the camera can be viewed together with the subject image from the objective lens 2.

The effect of the fourth embodiment thus constructed is almost the same as that of the above-mentioned first to third embodiments.

FIG. 6 shows a fifth embodiment of the present invention. The fifth embodiment is different from the first embodiment only in the configuration of the panoramic field mask and the switching means thereof, and the other parts are almost the same configuration, and therefore the same members are used for the same function. The reference numerals are given and the description thereof is omitted. As shown in FIG. 7, the panoramic field-of-view mask 41 of the fifth embodiment has elongated U-shaped holes 41a and 41b indicating the field-of-view range in the normal shooting state, and the field-of-view range in the panoramic shooting state inside thereof. The elongated linear holes 41c, 41d shown
However, a cross-shaped hole 41e that indicates the center of the photographic screen is also formed substantially at the center of the field-of-view mask 41. In addition, these holes 41a, 41b, 41c, 41
A member formed of a transparent or translucent material that allows light to pass through only the portions d and 41e may be fitted.

Further, behind the panoramic field mask 41, a substantially rectangular light-shielding plate 42 is provided so as to be vertically movable by a support rod 9. The light shielding plate 42 is a rectangular plate member having a vertical width slightly smaller than the distance between the U-shaped hole 41a and the linear hole 41d, and the linear hole 41c and the cross-shaped hole 41e are formed in the center thereof. A rectangular hole 42a having a vertical width slightly larger than the distance between the linear holes 41c and a horizontal width slightly longer than the length of the linear hole 41c is formed (see FIG. 7B). The light shielding plate 42 has its corners cut out in a triangular shape so as not to block the bent portions of the U-shaped holes 41a and 41b during panorama display.

As shown in FIG. 7 (A), a light-shielding plate 42 is used to form an elongated linear hole 41 showing the field of view in the panoramic photographing state.
When the c and 41d are shielded from light, the visual field range in the normal photographing state is observed. On the other hand, as shown in FIG. 7B, the shading plate 42 is moved upward, for example, by the switching operation of the panorama switching means (not shown). Then, when the light passes through the elongated linear holes 41c and 41d indicating the visual field range in the panoramic photographing state, the visual field range in the normal photographing state and the visual field range in the panoramic photographing state are simultaneously observed. Has become.

The effects of the fifth embodiment thus constructed are almost the same as those of the above-mentioned first to fourth embodiments.

[0031]

As described above, according to the present invention, it is possible to provide a finder device in which dust and dirt do not enter the vicinity of the image plane of the objective lens.

[Brief description of drawings]

FIG. 1 is a perspective view of a finder device showing a first embodiment of the present invention.

FIG. 2 is a perspective view of a finder device showing a second embodiment of the present invention.

FIG. 3 is a perspective view of a finder device showing a third embodiment of the present invention.

FIG. 4 is a perspective view of a finder device showing a fourth embodiment of the present invention.

FIG. 5 is a perspective view mask of the fourth embodiment,
(A) A front view showing a normal photographing state, and (B) a front view showing a panoramic photographing state.

FIG. 6 is a perspective view of a finder device showing a fifth embodiment of the present invention.

7A and 7B are a front view showing a normal photographing state and a front view showing a panoramic photographing state of a panoramic view mask and a shielding plate of the fifth embodiment.

[Explanation of symbols]

 3, 11b, 22c ... Imaging plane 3a, 11c, 22e ... Field of view frame 5, 12, 23 ... Half mirror 6, 14, 25 ... Eyepiece 7, 15, 26, 31, 41 ... Panoramic field of view mask 8, 42 ... Light shield

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[Procedure amendment]

[Submission date] December 24, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

[0003]

However [0007], than those described in JP above Hei 3-249400, visual
Since the field switching movable part is near the image forming surface of the objective lens with the field frame , dust and the like are likely to enter, and since the image forming surface is magnified by the eyepiece, dust and the like may exist. There was a problem that it was noticeable.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

[0005]

In order to achieve the above object, the finder apparatus according to the present invention operates to switch a photographing mask for defining an exposure range of a film between a normal photographing range and a photographing range of a different size. In a viewfinder device in which the viewfinder frame can be switched between the first viewfinder frame for the normal shooting range and the second viewfinder frame for the shooting range of a different size in conjunction with the Of a real-image finder optical system that forms an image on the image-forming surface that defines the field of view of the finder and guides the image to the eyepiece lens, and the exposure range that is located in an optical path different from the optical path of this real-image finder optical system. A light flux regulating means for transmitting a light flux corresponding to the second viewfinder field frame when switching to a shooting range of a size different from the range; The light beam transmitted through the light beam defining means are combined to the first finder field frame, characterized by comprising a beam combining means for incident on the eyepiece.
Also, the finder device according to the present invention is used for exposing a film.
The shooting mask that defines the range is different from the normal shooting range.
Linked to the switching operation to switch to a shooting range of
Match the viewfinder frame to the switched shooting mask.
For a finder device that switches to the appropriate finder field frame
At this point, the subject image is formed on the image plane and the image is erected.
Real-image viewfinder optics guided to the eyepiece through image means
System and the optical path of this real-image finder optical system
Equivalent to the above-mentioned switched photographing masks provided in the road
Transmits the light flux to define the viewfinder field frame
The luminous flux regulating means and the light transmitted through the luminous flux regulating means are
Combine with the light flux of the finder optical system and enter the eyepiece lens above.
And a luminous flux synthesizing means for illuminating the light.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

[0006]

A real image type finder optical system forms a subject image on at least an image forming surface that defines a viewfinder field for normal photographing, guides the image to an eyepiece lens, and an exposure range having a size different from that of the normal photographing range. When switched to the range, the light flux defining means transmits the light flux corresponding to the second finder field frame, and the light flux synthesizing means synthesizes the light flux passing through the light flux defining means into the first finder field frame to form the eyepiece. Let the light enter the lens. In addition, the real image finder optical system
However, the image of the subject is formed on the image forming surface and the image is erected.
This real image finder light is guided through the steps to the eyepiece.
Luminous flux regulating means provided in an optical path different from the optical path of the academic system
However, the fine
The light flux for defining the field frame is transmitted,
The step transmits the light transmitted through the luminous flux regulating means to the finder light.
It is combined with the light flux of the academic system to enter the eyepiece lens.

Claims (2)

[Claims] 1. A first viewfinder field frame for the normal shooting range is linked to an operation of switching a shooting mask that defines an exposure range of a film between a normal shooting range and a shooting range of a size different from the normal shooting range. And a second finder field frame for a shooting range of a different size from the above, in a viewfinder device, a subject image is formed on at least an image forming surface that defines the viewfinder field for normal shooting, and the image is viewed. It is located in an optical path different from the optical path of the real image type finder optical system that leads to the lens, and when the exposure range is switched to a shooting range of a size different from the normal shooting range, the second A light flux defining means for transmitting a light flux corresponding to the viewfinder field frame, and a light flux passing through the light flux defining means are combined into the first viewfinder field frame. And a light flux synthesizing means for allowing the light to enter the eyepiece lens. 2. The light flux defining means includes an aperture member representing the second viewfinder field frame, and a shield means for shielding the transmitted light flux from the aperture member when the normal photographing range is selected. The finder device according to claim 1, further comprising: