JP2001100277A - Finder device and camera provided therwith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a finder device realizing the miniaturization of a housing by bending an optical path for lighting on a vertical surface and folding it to be compact, and a camera equipped therewith. SOLUTION: The light to illuminate the mask of a frame 11 is made to illuminate mainly from the lower part of objective lenses 2 and 3 and transmitted through the frame 11, so that the shape of the mask is viewed in a state where it is synthesized with a field image by a half mirror 4.

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 a camera having the same.

[0002]

2. Description of the Related Art Conventionally, a lens shutter type camera as an optical photographing apparatus includes a photographing optical system for photographing a subject and a finder optical system for indicating a photographing range that can be photographed by the photographing optical system for determining the composition of the subject. have.
In a finder optical system of a camera, there is known a daylighting type bright frame finder in which a frame for indicating a shooting range is provided in the field of view, and the frame is illuminated by lighting from the outside.

In a conventional camera having a 135-type angle of view, a format having a shooting screen size of 24 mm × 36 mm is used. In this format, the ratio between the height and the width does not change so much, and the height is small. It was relatively long. Therefore, when providing a lighting type finder device with a conventional camera having a 135-type angle of view, if the light path for lighting is bent on a vertical plane, the height of the camera becomes high. For,
It was hardly adopted except for a tall camera such as a disk camera or a so-called instant camera.

A viewfinder constructed by bending an optical path for daylighting on a vertical plane is disclosed in, for example,
There is a "lighting type bright frame finder" described in Japanese Patent No. 33455, and this invention has a so-called ceiling lighting type configuration in which a lighting window is provided on the upper surface of the body.

[0005] However, such a finder device of the ceiling lighting type is generally hardly seen and hardly adopted because light from above is often blocked by hair or an eave of a hat.

[0006] For this reason, a finder device of the type that illuminates a frame has conventionally been disclosed in, for example, Japanese Patent Application Laid-Open
As described in Japanese Unexamined Patent Application Publication No. 09-93856 and Japanese Unexamined Patent Application Publication No. 7-261242, most of the optical paths have a configuration in which the optical path is bent on a horizontal plane.

[0007]

By the way, in recent cameras, a so-called new photographic system using 1 × 240 film has been introduced.
A format having a shooting screen size of 7 mm × 30.2 mm in width is used. And in recent years, using the horizontal characteristics of this format, where the vertical width is shorter than the horizontal width,
A proposal has been made for a finder device provided in a camera housing to have a configuration in which an optical path for lighting and illuminating a frame is bent in a vertical plane.

Here, when the light path for lighting is bent by a vertical plane, for example, if the lighting optical axis and the optical axis of the viewing light are made parallel, the height of the housing becomes too high. was there. In addition, if the window for the viewfinder image is provided separately from the lighting window, the front of the camera becomes full of windows, and the strength of the housing becomes insufficient.

An object of the present invention is suitably applied to a camera of a new photographic system, and includes a finder device in which a light path for daylighting is bent on a vertical plane to be compactly folded to reduce the size of a housing, and a finder device. It is to provide a camera.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the finder device of the present invention comprises: an objective lens for receiving light of a field image; an eyepiece for outputting light of a field image;
A frame having a mask portion that transmits light incident from the lower part of the objective lens, and the reflection surface is disposed between the objective lens and the eyepiece with the reflection surface facing downward, and light incident on the objective lens,
A half mirror for combining light entering from the lower part of the objective lens and passing through the mask portion to the eyepiece, and a total reflection mirror disposed below the half mirror and guiding the light passing through the mask portion to the half mirror are provided.

Here, the frame is arranged between the objective lens and the total reflection mirror. Thereby, space saving in the height direction is achieved, and the optical path formed between the total reflection mirror and the frame is compactly folded.

The frame is illuminated by external light entering the objective lens from obliquely above the light of the field image.

Thus, the window portion for the light path for lighting and the light path for the visual field image can be shared, and it is not necessary to provide a separate window for lighting.

Further, by making the height of the combined half mirror and frame substantially equal to the height of the objective lens, space saving in the height direction can be achieved.

In the camera according to the present invention, in order to solve the above-mentioned problems, any one of the above-described finder devices is provided at an upper portion of a housing.

Further, by disposing the film feeding mechanism below the objective lens, the height of the camera housing can be kept low.

[0017]

Embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a description will be given with reference to FIG. 1 showing a longitudinal section of a main part of a camera provided with a finder device.

In this camera, as shown in FIG. 1, the objective window 1 is mounted on the upper front side of an outer cover 22 as a housing, and the eyepiece window 6 is mounted on the upper rear side of the outer cover 22. In the space between the window 1 and the eyepiece window 6, an A objective lens 2, a B objective lens 3, a half mirror 4,
It has a configuration in which a convex eyepiece 5 is arranged in order. The objective lenses 2 and 3 and the half mirror 4 are mounted on a lower finder base plate 20 in the outer cover 22, and the total reflection mirror 9 and the frame 11 are mounted on the finder base plate 20. A finder device is constituted by these optical members.

In the finder device, members other than the objective window 1 and the eyepiece window 6 are covered from above by a finder cover 21 attached to the finder base plate 20, and are unitized. A camera film feed mechanism and the like are arranged below the finder cover 21. Specifically, a feed gear train 26 for feeding a film (not shown), a main body member 23, and a pressure plate 2 are provided.
4. A shutter unit 25 is provided.

The half mirror 4 is inclined between the objective lens 3 and the eyepiece 5 so that the mirror surface faces downward, and the lower end is close to the objective lens 3 and the upper end is close to the eyepiece 5. And located. As a result, the half mirror 4 transmits most of the light traveling from the objective lens 3 to the eyepiece 5 and supplies the light to the eyepiece 5.
The mirror surface of the half mirror 4 reflects the light from the total reflection mirror 9 on a plane perpendicular to the eyepiece 5.

In this embodiment, the half mirror 4 is configured to have a short width in the vertical direction by utilizing the fact that the angle of view in the vertical direction of the new photographic system is small.

The total reflection mirror 9 is disposed below the half mirror 4, and has an upper end located close to the eyepiece 5. The size of the total reflection mirror 9 is smaller than the size of the half mirror 4, and the size of the frame 11 is smaller than the size of the total reflection mirror 9.

The frame 11 is located below the half mirror 4 and close to below the objective lens 3. The upper end of the frame 11 is close to the lower end of the half mirror 4. In this embodiment, as shown in FIG. 1, the combined height of the half mirror 4 and the frame 11 is substantially equal to the height of the objective lens 3, so that space in the height direction is saved. . Also, half mirror 4,
The arrangement of the total reflection mirror 9 and the frame 11 is accommodated within the distance between the objective lens 3 and the eyepiece 5, thereby saving space in the depth direction. Further, since the arrangement of the frame 11 is on the rear side of the objective lens 3, an optical path formed between the total reflection mirror 9 and the frame 11 described later is compactly folded.

The frame 11 is provided with a mask including a transmissive portion indicating an angle of view, and a cover for selectively opening the mask. Depending on the degree of opening of the cover, the C (Classic) type, H (Hivision) type, A P (Panorama) type frame shape having each aspect ratio can be selected.

In the finder device, the objective lenses 2, 3
Light 7e from the obliquely upper left front direction in FIG. 1 guided by the transparent portion at the bottom of FIG. 1 irradiates the frame 11, reflects the transmitted mask-shaped image by the total reflection mirror 9, and further reflects the mirror surface of the half mirror 4. Is irradiated. The objective lens 3
The lower portion 3a may be a matte surface for improving light diffusivity, or a thin milky white plate may be attached to improve the diffusivity.

In the finder device according to the embodiment, light from an object (field image) is parallel to central lights 7a and 7b.
Through the objective window 1 and refracted by the objective lenses 2 and 3,
Most of the light passes through the half mirror 4 and travels along the first optical path, is refracted by the eyepiece lens 5 and exits from the eyepiece window 6 as output light 7c and 7d.

The optical system of the finder device including the objective lenses 2 and 3 and the eyepiece 5 is equivalent to a concave lens, and therefore the output lights 7b and 7d are not parallel to each other. Further, in this finder device, as shown by a dotted line in FIG. 1, light from an object enters the eyepiece 5 as if coming out of a point (hereinafter, referred to as a temporary light source) 8 in the objective window 1. It is visually recognized by an observer through the eyepiece window 6.

On the other hand, through the objective window 1, the objective lenses 2, 3
The light from the object side that has transmitted mainly through the lower part of the image is reflected by the mirror surface of the frame 11, the total reflection mirror 9, and the half mirror 4 having the mask (transmission part) having transmitted the image through the mask, The light is combined with the first optical path, travels, is refracted by the eyepiece lens 5, and exits through the eyepiece window 6.

In the finder device, FIG.
Is a point conjugate with the temporary light source 8 in the objective window 1 (hereinafter, referred to as a conjugate point 10), and the frame 11 is arranged so that the approximate center thereof is located at the conjugate point 10.
With such a configuration, in the finder device, the light emitted from the conjugate point 10 on the frame 11 and the central light 7
a and 7b are combined by the half mirror 4 and viewed from the eyepiece window 6 side as light coming from the same place.

In this finder device, FIG.
As shown in (2), the frame 11 is effectively illuminated by external light that is obliquely incident on the light from the object, and transmits light that matches the shape of the mask of the frame 11.

As described above, in the finder device according to the embodiment, since the frame 11 is effectively illuminated by the external light that enters the objective window 1 from an obliquely upward direction, a separate lighting window for external light is provided. No need. In other words, in this viewfinder device, the lighting window and the optical path
Since it is also used as a window for viewing and an optical path, cost reduction is achieved, and weight reduction is realized.
Since the number of windows is reduced, the strength of the housing is maintained, and a finder and a camera that are simple in design can be obtained.

The half mirror 4, the total reflection mirror 9,
In addition, the second optical path for illuminating the frame 11 can be formed by arranging the frame 11 within the distance between the objective lens 3 and the eyepiece 5 and arranging the frame 11 at the rear lower end of the objective lens 3. It is compactly folded on the vertical plane behind the objective lens 3.

Further, by setting the lighting direction to be obliquely upward, the entire light path is compactly folded by sharing the light path for lighting and the light path for the field-of-view image. 3, a feed gear train 26 for feeding the film.
The height of the entire camera is reduced by placing
The outer cover 22 as a housing is made compact.

The finder device of the present embodiment has a large objective lens and an eyepiece, and can be effectively applied to a relatively low magnification high eye point type. That is, in the embodiment, the focal length of the concave / convex lens for achieving low magnification is short, and the position of the temporary light source 8 is close to the eyepiece lens 5.

[0035]

As described above, according to the present invention,
The present invention is suitably applied to a camera of a new photo system, and it is possible to provide a finder device in which a light path for lighting is bent in a vertical plane to be compactly folded to reduce the size of a housing, and a camera including the finder device. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of a camera provided with a finder device to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Objective window 2 ... A objective lens 3 ... B objective lens 4 ... Half mirror 5 ... Eyepiece 6 ... Eyepiece window 7a, 7b ... Central light 7c, 7d. ..Output light 7e: Light from obliquely upward direction 8: Point (temporary light source) 9: Total reflection mirror 10: Point (conjugate point) 11: Frame 20: Finder ground plane 21 finder cover 22 outer cover 23 body 24 pressure plate 25 shutter unit 26 feed gear train

Claims (6)

[Claims] 1. An objective lens for receiving light of a visual field image, an eyepiece for outputting light of a visual field image, a frame having a mask portion for transmitting light incident from below the objective lens, and the objective lens A half arranged with the reflecting surface downward between the eyepiece and the light incident on the objective lens, and the light incident on the lower part of the objective lens and transmitted through the mask unit, and combined with the eyepiece. A finder device comprising: a mirror; and a total reflection mirror disposed below the half mirror and guiding light transmitted through the mask unit to the half mirror. 2. The finder device according to claim 1, wherein the frame is disposed between the objective lens and the total reflection mirror. 3. The finder device according to claim 1, wherein the frame is illuminated by external light having entered the objective lens from an obliquely upward direction with respect to light of a visual field image. 4. The finder device according to claim 1, wherein a combined height of the half mirror and the frame is substantially equal to a height of the objective lens. 5. A camera, wherein the finder device according to claim 1 is provided on an upper part of a housing. 6. The camera according to claim 5, wherein a film feeding mechanism is disposed below the objective lens.