JP2002090819A - Finder device and optical equipment using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a finder device with which indicating marks displayed within a finder screen and a finder screen are observed properly by superimposing them, and to prove optical equipment using it. SOLUTION: In the finder device, with which both a subject picture formed on a display board and the indicating marks are observed by irradiating the indicating marks formed on the display board with luminous fluxes from respective illuminating means, the indicating marks of the display board respectively possess a plurality of groups of microprisms, and the ridge line direction of the microprisms of some of the indicating marks is aligned in a direction which is nearly in parallel with a straight line drawn from the center of the display board to that indicating marks.

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 an optical apparatus using the same, and more particularly to a finder device (also referred to as "finder optical system" or "finder system") used for a single-lens reflex camera or a twin-lens camera. ), A photographic camera and a video camera in which both a subject image formed on a reticle by a photographing lens and information of a display (display index) such as distance measurement information are superimposed and observed in the same field of view. It is suitable for digital cameras and the like.

[0002]

2. Description of the Related Art Conventionally, in an optical device such as a single-lens reflex camera, display indices such as a photometry area and a focus detection area on a photographing screen are displayed by being superimposed on a subject image in a viewfinder (viewfinder field). Some viewfinder display devices (viewfinder devices) for observing images at the same time have been proposed.

First, a finder display device of a general single-lens reflex camera will be described. FIG. 6 shows a conventional finder screen. In FIG. 6, F is a viewfinder screen of the camera. F1, F2, F3, F4, and F5 are display indices provided corresponding to the focus detection area and the photometry area on the photographing screen of the camera. The display indices F1 to F5 have a rectangular outline shape, and each side is drawn so as to be parallel to the long side direction or the short side direction of the finder screen F. F6 is an information display section, which is arranged below the finder screen F.

FIG. 7 is a diagram showing the relationship between a focusing screen S used in the conventional finder device shown in FIG. 6 and an illumination optical system (illumination light source). Sm is a mat surface,
This is a surface on which a subject image is formed by the taking lens. Sf denotes a Fresnel lens, which is formed on the opposite side to the matt surface Sm. The Fresnel lens Sf is formed concentrically around the center Sa of the focusing screen S. The Fresnel lens Sf is provided to keep the exit pupil of the photographing lens and the eyeball of the observer in an imaging relationship and to obtain a viewfinder image without shadow. S1, S2, S3, S
Reference numerals 4 and S5 denote an aggregate of minute prisms, which correspond to the display indices F1, F2, F3, F4 and F5 described with reference to FIG. 6, respectively, and are formed on the mat surface Sm. Each of the small prisms is formed by a wedge-shaped prism,
The direction of the ridge line of the peak of the prism is formed parallel to the longitudinal direction of the reticle S. L1, L2, L3, L4, and L5 are light sources for illuminating the aggregates S1, S2, S3, S4, and S5 of the micro prisms, respectively. In the finder display device having this configuration, the sides of the display indices F1 to F5 are drawn so as to be parallel to the long side direction or the short side direction of the finder screen F.

In FIGS. 6 and 7, display indices F2, F3,
Illumination optical axis for irradiating F5 and display indices F2, F3, F5
Are parallel or orthogonal to each other. However, for the display indices F1 and F4, the illumination optical axis is not parallel or orthogonal to each side of the display indices. Therefore, the irradiation light to the display indices F1 and F4 enters at an oblique angle in the range of 0 ° to 90 ° with respect to the direction of each side.

FIG. 8 is a side view of a main part of a camera using the above-described conventional finder display device. FIG. 9 is a perspective view of a part of the optical system of FIG. In FIGS. 8 and 9, L is a photographing lens (two-dot chain line). 10
1 is a camera body. Reference numeral 102 denotes a mirror box (two-dot chain line), and reference numeral 103 denotes a camera mount attached to the mirror box 102. 104 is a shutter device. 105 is a film surface. Reference numeral 106 denotes a main mirror, which transmits a part of the photographing light beam from the photographing lens L and reflects the remaining light beam. 107 is a submirror. Reference numeral 108 denotes a focus detection device, which is disposed below the sub-mirror 107 and below the mirror box 102.
Reference numeral 109 denotes a reticle (the same as the reticle S in FIGS. 6 and 7), which is disposed at a position which is approximately the same as the film surface 105.
110 is a pentaprism. Reference numeral 111 denotes an eyepiece. Reference numeral 112 denotes a photometric lens. 113 is a photometric sensor. 114a, 114b, 114c, 114
Reference numerals d and 114e denote light emitting elements of a finder illumination light source. 115 is a light projecting prism. Reference numeral 116 denotes a light projection mask. Light emitting elements 114a, 114b, 114c, 11
The illumination light irradiated from 4d and 114e
16, a set of micro prisms S 1, S formed on the focusing screen 109 via the light projecting prism 115 through the aperture 16
Irradiation is performed on each of S2, S3, S4, and S5.

As another method of displaying the display index on the finder screen, an eyepiece in the finder optical path or a condenser lens disposed above the focusing screen is provided with a light splitting means, and the light splitting means is provided through the light splitting means. There is a method in which a desired display is superimposed and displayed in a shooting screen.
According to this method, the arrangement of the light emitting element serving as the light source and the light projecting optical system is above the eyepiece or above the pentaprism. The light splitting means used in this method is very complicated and expensive. This method is disclosed in
36858.

[0008]

In the finder display device having the configuration shown in FIGS. 6 to 9, display indices F1 to F5 indicating a focus detection area and a photometry area are arranged at corresponding positions on the finder screen F. I have. In recent finder screens, the number of areas that can be detected is increasing not only in the horizontal direction but also in the vertical direction of the shooting screen. Therefore, display indices corresponding to these increased focus detection areas must be provided on the finder screen. That is, a plurality of display indices must be provided not only in the horizontal direction but also in the vertical direction of the shooting screen. By the way, when illuminating a plurality of display indices arranged in a horizontal direction, a vertical direction, or other positions on a finder screen by using an illumination light source arranged only in front of a pentaprism as in the related art shown in FIG. From the relationship between the illuminating light flux and the index position, the ridge direction of the micro prisms provided on the reticle and the concentric prism ridges of the Fresnel lens provided on the reticle at the position where the display index is located. The relative angle with the ridge line direction is close.
That is, it approaches 90 from 90 °.

As described above, if the angle between the ridge line direction of the mountain of the Fresnel lens and the ridge line direction of the micro prism is close to or coincide with each other, the range irradiated with the illuminating light is not limited by the Fresnel lens regardless of the shape of the index. Since it looks shiny, the display index cannot be confirmed. In addition, since an extra light flux is also guided to the eyes, a ghost occurs.

Further, in the finder display device having the above-described configuration, each side of the display index is drawn so as to be parallel to the long side direction or the short side direction of the finder screen. Are not always parallel to each side (display indices). In other words, the irradiation light is incident at an oblique angle in the range of 0 ° to 90 ° with respect to the direction of each side of the index, and the display index may appear blurred or jagged. Grade had deteriorated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a finder display device capable of clearly observing a plurality of display indices on a finder screen with little ghost and an optical apparatus using the same.

[0012]

According to a finder device of the present invention, a plurality of display indices formed on a display panel are irradiated with a light beam from an illuminating means, respectively, and a subject image formed on the display panel and the subject image are illuminated. In a finder device for observing both display indices, each of the plurality of display indices on the display plate has an aggregate of a plurality of microprisms, and among these, some of the display index microprisms are located from the center of the display plate to the center. The ridge line direction of the minute prism is formed in a direction substantially parallel to a straight line drawn toward an arbitrary display index among the plurality of display indexes.

According to a second aspect of the present invention, in the first aspect of the present invention, the display panel has a lens portion having a predetermined curvature in a predetermined region in a center portion, and a plurality of continuous concentrically extending lenses in an outer peripheral region of the lens portion. Is characterized in that a Fresnel lens composed of the above prism is formed.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the illuminating means is on a plane formed by a vertical line of the display index with respect to a ridge direction of the micro prism and a normal line to the display plate. The display index is illuminated with illumination light having an illumination optical axis parallel to the plane.

According to a fourth aspect of the present invention, in the first, second or third aspect of the present invention, any of the plurality of display indices provided on the display panel is provided by the illumination means for illuminating the display indices. It is characterized by forming a contour shape drawn in a direction substantially coincident with a direction parallel or perpendicular to a plane including the illumination optical axis.

According to a fifth aspect of the present invention, in the second aspect of the present invention, the minute lens of a part of the plurality of display indices is displayed with respect to the ridgeline direction of the mountain of the concentric prism of the Fresnel lens. The feature is that the ridge direction of the mountain is substantially vertical.

According to a sixth aspect of the present invention, there is provided an optical apparatus using the finder device according to any one of the first to fifth aspects.

[0018]

(First Embodiment) A first embodiment of a finder device (finder) of the present invention will be described with reference to FIGS. FIG. 1 is a view showing a viewfinder screen of a camera (optical device), FIG. 2 is a view showing a relationship between a focusing screen (display board) used for the viewfinder and an illumination light source, and FIG. FIG. 4 is a side view of a main part of a camera using the focusing screen, and FIG. 5 is a perspective view of a main part of the finder device viewed obliquely from the front.

Next, the configuration of this embodiment will be described.
First, the finder screen will be described with reference to FIG. F
Is a shooting screen in the finder screen. f1 to f
Reference numerals 5 indicate display indices in the photographing screen F, each corresponding to a detection area such as a focus detection sensor or a photometric sensor. f1 is a display index at the center of the shooting screen. f2
f3 is a display index provided on the horizontal line H passing through the center of the photographing screen at a predetermined interval left and right with respect to the central display index f1. f4 and f5 are display indices provided on the vertical line V passing through the center of the photographing screen at predetermined intervals above and below the center display index f1.
fi is an information display unit provided in the viewfinder,
An information display unit that displays shooting information such as a shutter speed, an aperture value, and an exposure correction value.

Next, a reticle (display panel) of one element constituting a finder will be described with reference to FIGS. S
Reference numeral denotes a reticle (display plate) for forming a subject image from the taking lens. Sm is a mat surface on the upper surface side (observation side) of the focusing screen S. Sf is a Fresnel lens provided on the lower surface side of the focusing screen S. The Fresnel lens Sf has a lens portion having a predetermined curvature in a predetermined region in the center of the reticle S and acting as a lens. The Fresnel lens is composed of a plurality of continuous prisms concentrically spreading in the outer peripheral direction. It is configured.

In FIG. 2, the dashed line indicates the ridge line of the concentric prism. S1 to S5 are formed on the mat surface Sm side of the reticle S, and are aggregates of micro prisms having a wedge-shaped cross section. Each of the aggregates S1 to S5 of the micro prisms is disposed at a position corresponding to the detection area of the focus detection sensor or the photometric sensor. Observe these micro prisms as display indices f1 to f5 in the finder screen F. become. S1 is an aggregate of minute prisms at the center of the photographing screen.

Each of the micro prisms constituting the assembly S1 has a cross section in the shape of a wedge-shaped mountain, and its ridge line direction is the short side direction of the focusing screen S, that is, the vertical direction V of the finder screen. Match. Aggregates S2 and S3 are reticle S
Are provided at predetermined intervals in the left-right direction with respect to the central micro prism assembly S1 on a horizontal line H passing through the center of. Each of the micro prisms constituting the aggregates S2 and S3 has a wedge-shaped mountain shape in cross section, and its ridge line direction coincides with the long side direction of the reticle S, that is, the horizontal direction H of the finder screen. I do. The aggregates S4 and S5 are provided on a vertical line passing through the center of the reticle S at a predetermined interval in the vertical direction with respect to the central aggregate S1 of micro prisms. Each of the micro prisms constituting the aggregates S4 and S5 has a wedge-shaped mountain shape in cross section, and its ridge line direction corresponds to the short side direction of the focusing screen S, that is, the vertical direction V of the finder screen. I do. Therefore, except for the aggregate S1 of the micro prisms, the ridge direction of the peaks of the micro prisms of the aggregates S2 to S5 is orthogonal to the ridge direction of the mountain of the concentric prism forming the Fresnel lens Sf at each position. .

A collection of micro prisms S1, S2, S3
S4 and S5 are the display indices f1 and f1 of the finder screen described above.
These correspond to f2, f3, f4, and f5, respectively. Since the reticle S is observed through a pentaprism and an eyepiece described later, the photographer moves the reticle S to the vertical line V
In the left-right inverted state.

According to the present embodiment as described above,
At the position of an arbitrary display index, the ridge direction of the ridge of the micro prism constituting the display index is substantially perpendicular to the ridge direction of the ridge of the concentric prism of the Fresnel lens formed on the focusing screen (90 ° ± 10 °). °).
As a result, the illumination light for irradiating the display index can be made incident from a plane parallel to the ridgeline of the mountain of the Fresnel lens. Never reach. This provides a clear, easy-to-see viewfinder image without ghosts.

Next, the arrangement of the illumination light source with respect to the reticle S will be described with reference to FIG. P2 is a plane perpendicular to the reticle S that includes a tangent t2 to the ridge line of the concentric Fresnel lens Sf at the center position of the micro prism assembly S2. L2 is an illumination light source (illumination means) on the same plane P2 and arranged at a predetermined angle with respect to the reticle S. Here, the lighting means has a light emitting element and a light projecting lens for projecting a light beam from the light emitting element. This is the same in the following lighting means.

The illuminating light emitted from the illuminating light source L2 in the direction of the aggregate S2 is first refracted by the Fresnel lens Sf toward the center of the reticle, and the luminous flux passing through the micro prism S2P is at a predetermined angle. The light is refracted, transmitted through the reticle S, guided to an eyepiece described later, and reaches the eyes of the observer. The light flux that has not passed through the micro prism S2P does not reach the eyes of the observer. Therefore, only the portion where the micro prisms S2P are formed appears brightly to the observer's eyes. At this time, the ridge direction of the peaks of the prisms forming the Fresnel lens Sf and the ridge direction of the peaks of the micro prisms forming the assembly S2 are orthogonal or substantially perpendicular, so that the Fresnel lens S around the assembly S2.
f does not look shiny.

P5 is a plane perpendicular to the focusing screen S, including a tangent t5 to the ridge direction of the concentric Fresnel lens Sf at the center position of the micro prism assembly S5.
L5 is an illumination light source located on the same plane P5 and arranged at a predetermined angle with respect to the reticle S. The illuminating light emitted from the illuminating light source L5 assembly in the direction of S5 is first refracted by the Fresnel lens Sf toward the center of the reticle, and the luminous flux passing through the micro prism S5P is refracted by a predetermined angle. Then, the light passes through the reticle S and is guided to an eyepiece described later, and reaches the eyes of the observer.

The light beam that has not passed through the micro prism S5P does not reach the eyes of the observer. Therefore, only the portion where the micro prism S5P is formed appears brightly shining to the observer's eyes. At this time, the ridge direction of the peak of the prism forming the Fresnel lens S5 and the ridge direction of the peak of the micro prism S5P forming the assembly S5 are also orthogonal at this position, so that the Fresnel lens around the assembly S5. Sf does not look shiny. The positions of the illumination light sources may be set while maintaining the same relationship for the other aggregates S3 and S4 of the micro prisms. However, the central portion of the reticle S is a region where the peak of the concentric prism of the Fresnel lens Sf does not exist, and therefore the prism S constituting the aggregate S1 is formed.
The ridge direction of the 1P mountain may be set arbitrarily.

The arrangement of the illumination light sources (illumination means) L1, L2, L3, L4, and L5 shown in FIG. 2 is merely a diagram for explaining the concept of the optical system, and is an actual arrangement of the camera. In this case, it is sufficient that the arrangement is optically equivalent to that of FIG.

Next, the arrangement of the reticle and the illumination light source in the camera of the present invention will be described with reference to FIGS. 1
Is a camera body. Reference numeral 2 denotes a mirror box (two-dot chain line), and reference numeral 3 denotes a camera mount attached to the mirror box 2. Reference numeral 4 denotes a shutter device. Reference numeral 5 denotes a film surface (imaging surface). Reference numeral 6 denotes a main mirror, which transmits a part of the photographing light beam from the photographing lens L and reflects the remaining light beam. 7 is a submirror. Reference numeral 8 denotes a focus detection device, which is arranged below the sub-mirror 7 and below the mirror box 2. Reference numeral 9 denotes a reticle, which is disposed at a position optically conjugate with the film surface 5. The focusing plate 9 has the above-mentioned aggregates S1, S2, S3, S4 of the micro prisms.
S5 is formed. Reference numeral 10 denotes a pentaprism (image inversion means). Reference numeral 11 denotes an eyepiece. Reference numeral 12 denotes a photometric lens. Reference numeral 13 denotes a photometric sensor. 14a, 1
Reference numeral 4b denotes a light emitting element disposed immediately before the pentaprism 10. Reference numeral 15 denotes a light projecting prism for the light emitting elements 14a and 14b. Reference numeral 16 denotes a light projection mask. 17a, 1
Reference numerals 7b and 17c are light-emitting elements arranged on the side surface of the mirror box 2. 18 is a light emitting element 17a, 17b, 17c
Is a light projecting prism. 19 is a light projection mask.

Next, the finder light beam and the illumination light beam will be described. A part of the photographing light passing through the photographing lens L is transmitted by the main mirror 6, reflected downward by the sub-mirror 7, guided to a known focus detection device 8, and focused on the output of the focus detection device 8. Adjustments are made. The photographing light reflected by the main mirror 6 forms a subject image (finder image) on the focusing screen 9. The subject image on the reticle 9 is
The light is guided to the eyepiece 11 through the pentaprism 10 and observed by the photographer. Part of the subject image formed on the reticle 9 passes through the photometric lens 12 and passes through the photometric sensor 1.
3 and the brightness of the subject is detected.

On the other hand, the light emitting elements 14a and 14b of the finder illumination light source disposed immediately before the pentaprism 10
The illumination light emitted from is incident on the light projecting prism 15,
The light is changed in direction by being totally reflected inside the prism, exits from the lens portion 15a, and enters the main mirror 6 from the front of the main mirror 6. The illumination light is reflected by the main mirror 6, enters from below the reticle 15 at an angle different from that of the imaging light beam, and irradiates the reticle 9. Also,
The illumination light emitted from the light emitting elements 17a, 17b, 17c of the finder illumination light source arranged on the side surface of the mirror box enters the light projecting prism 18 and changes its direction by being totally reflected inside the prism. Lens part 18a
And enters the main mirror 6 from the side of the main mirror 6. Any finder illumination light is reflected by the main mirror 6 and enters from below the reticle 9 at an angle different from that of the photographic light beam to irradiate the reticle 9. Light emitting element 1
4a, 14b, 17a, 17b, and 17c are aggregates S2, S3, S1, S4, and S5 of micro prisms (see FIG. 2).
Are illuminating light sources for illuminating each of them. That is, the light emitting elements 14a, 14b, 17a, 17b, 17c
, L2, L3, L1, L4, and L5, respectively, and the arrangement of the illumination light sources is equivalent to that described with reference to FIG. Aggregation S of micro prisms
The light flux passing through each of 2, S3, S1, S4, and S5 is refracted and guided to the eyepiece 11 through the pentaprism 10, and is observed by the photographer as a glowing index on the finder screen shown in FIG. You. Also, when the light-emitting element as the illumination means does not emit light, no light is emitted from the aggregate of micro prisms toward the eyepiece 11, so that the display index in the finder screen is observed as black compared to the surrounding subject image. Is done. Since the above-described illumination light is incident on the reticle 9 from an angle different from the photographing light flux,
The light beam that has passed through the portion where the micro prism is not formed does not reach the eyepiece lens 11 and is not observed by the photographer. That is, when any of the above light emitting elements emits light,
At the corresponding index position, only the part where the micro prism is formed appears shining to the photographer.

(Embodiment 2) In the present embodiment, an embodiment 2 of the present invention will be described next. This is an example in which the number of display indices in the finder screen is further increased compared to the first embodiment.
Next, this embodiment will be described with reference to FIGS. FIG.
0 is a view showing a viewfinder screen of the camera, and FIG. 11 is a view showing a relationship between a focusing screen and an illumination light source used in the viewfinder. In FIG. 10, F is a photographing screen in the finder screen. f1 to f9 are display indices in the shooting screen, each corresponding to a detection area of the focus detection sensor or the photometry sensor. Display indices f1, f2
Since f3, f4, and f5 are the same as those in the first embodiment, the description will not be repeated. The display indices f6, f7, f8, f9 are arranged at positions deviated from the horizontal line H and the vertical line V. The display indices f6 and f8 pass through the photographing screen center Fa, and the horizontal line H
Are arranged on a straight line A which forms an angle between 0 and θ (0 <θ <90 °). The display indices f7 and f9 are arranged on a straight line B that forms an angle of θ with the horizontal line H (0 <θ <90 °).
Each of the display indices f6, f7, f8, and f9 has a rectangular outline shape. The display indices f6 and f8 are drawn as straight lines whose two sides are parallel to the straight line A and whose other two sides are perpendicular to the straight line. The display indices f7 and f9 are drawn as straight lines whose two sides are parallel to the straight line B and whose other two sides are perpendicular to the straight line A. fi is an information display section provided in the viewfinder, and is an information display section for displaying information such as a shutter speed, an aperture value, and an exposure correction value.

Next, a focusing screen corresponding to the above-described finder screen will be described with reference to FIG. S is a reticle that forms a subject image from the taking lens. Sm is a mat surface on the upper surface side of the focusing screen S. Sf is a Fresnel lens provided on the lower surface side of the focusing screen S. The Fresnel lens Sf has a lens function having a predetermined curvature in a predetermined area of the center portion Sa of the reticle S, and the Fresnel lens is formed of a prism that concentrically expands in the outer peripheral direction. In FIG. 11, what is indicated by a broken line is the ridge line of the concentric prism. S1 to S9 are formed on the mat surface Sm side of the reticle S, and are aggregates of micro prisms having a wedge-shaped cross section. Aggregates S1 to S of micro prisms
Numerals 9 are arranged at positions corresponding to the detection areas of the focus detection sensor or the photometric sensor, respectively. Aggregation S
Since 1, S2, S3, S4, and S5 are the same as those in the first embodiment,
Hereinafter, the description is omitted. Aggregation of small prisms S6, S
Each of the micro prisms 8 has a wedge-shaped mountain shape in cross section, and is formed such that the ridge direction is parallel to the straight line A. Each of the small prisms constituting the aggregates S7 and S9 of the small prisms has a wedge-shaped mountain shape in cross section, and is formed such that the ridge direction is parallel to the straight line B. . That is, the ridge direction of the ridges of the microprisms forming the aggregates S6, S7, S8, and S9 of the microprisms is orthogonal or substantially perpendicular to the ridge line direction of the prisms forming the Fresnel lens at each position (90 ° ± 10 °). The aggregates S6, S7, S8, and S9 of the micro prisms correspond to the display indices f6, f7, f8, and f9 on the finder screen. Since the reticle S is observed through the pentaprism, the photographer observes the reticle S in a state where the reticle S is horizontally inverted with respect to the vertical line V.

Next, the arrangement of the illumination light source with respect to the focusing screen S will be described with reference to FIG. L1 to L9 are illumination light sources for illuminating the aggregates S1 to S9 of the micro prisms, respectively. The illumination light sources L1, L2, L3, L4, and L5 are the same as those in the first embodiment, and a description thereof will not be repeated. The illumination light axes L6a, L7a, L6a, L7a of the illumination light sources L6, L7, L8, L9
L8a and L9a are orthogonal or substantially orthogonal to the ridge line direction of the micro prisms S6, S7, S8 and S9 to be illuminated. Therefore, the optical axes L6a, L7a, L8a, L9a of the illumination light source are located at any position of the micro prisms S6, S7, S8, S9.
And the direction of the ridgeline of the mountain of the concentric prism forming the Fresnel lens Sf is kept parallel. Therefore, the nearby Fresnel lens illuminated by the illumination light source does not appear to shine. Furthermore, since the direction in which the rectangular display index is drawn is substantially parallel or substantially perpendicular to the optical axis direction of the illumination light, the outline of the display index may be blurred or jagged. Never do.

The illumination light sources L6 and L6 shown in FIG.
The arrangement of L7, L8, and L9 is merely a diagram for explaining the concept of the optical system, and the actual camera arrangement may be any arrangement that is optically equivalent to FIG.

The finder device of the present invention is not limited to a single-lens reflex camera, but can be applied to other optical devices such as a video camera and a digital camera.

FIG. 12 is a schematic view of a principal part of a third embodiment in which the finder device of the present invention is applied to an optical apparatus using an external real image finder system.

In FIG. 12, reference numeral 35 denotes a transparent protective plate. Reference numeral 40 denotes an objective lens system having a zooming unit, which forms an object image (finder image) on a predetermined surface (primary imaging surface). Reference numeral 38 denotes a prism as one element constituting the image reversing optical system.

The image inversion optical system in this embodiment converts an inverted object image by the objective lens 40 into an erect erect image. In the figure, the prism constituting one element of the image inversion optical system is shown as a glass block in which an optical path is developed for simplicity. However, the image inversion optical system further includes a mirror, a prism, and the like.

Reference numeral 37 denotes a field lens. Reference numeral 36 denotes a focusing screen as a display board, on which the objective lens 4 is provided.
An object image with 0 is formed. Reference numeral 34 denotes an eyepiece lens for observing an object image of an erect erect image formed on the focusing plate 36 and a display index.

The structure of the reticle 36 is the same as that shown in each of the above embodiments. L1 to L5 (only L3 and L4 are shown in the figure) are light sources constituting the illuminating means, and the positional relationship between the illuminating means and the reticle 36 is the same as in the above-described embodiment.

In this embodiment, both the subject image and the display mechanism can be observed in the same field of view, as in the case of applying the present invention to a single-lens reflex camera.

[0044]

According to the present invention, by setting each element as described above, a plurality of display indices on a finder screen can be clearly observed with little ghost and an optical apparatus using the same. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a view showing a finder screen in a finder device according to a first embodiment of the present invention.

FIG. 2 is an optical conceptual diagram of a reticle and an illumination light source according to the first embodiment of the finder device of the present invention.

FIG. 3 is an enlarged view of a cross section of a main part of the reticle shown in FIG. 2;

FIG. 4 is a side view of a main part of the optical apparatus of the present invention.

FIG. 5 is a perspective view of a part of the finder device of the present invention viewed obliquely from the front.

FIG. 6 is a diagram showing a finder screen of a finder device in a conventional camera.

FIG. 7 is a diagram showing details of a reticle used in a conventional camera.

FIG. 8 is a side view of a main part of a conventional camera.

FIG. 9 is a perspective view of a finder optical system in a conventional camera as viewed obliquely from the front.

FIG. 10 is a diagram showing a finder screen in a finder device according to a second embodiment of the present invention.

FIG. 11 is an optical conceptual diagram of a reticle and an illumination light source in a finder device according to a second embodiment of the present invention.

FIG. 12 is a schematic diagram of a main part of a finder device according to a third embodiment of the present invention.

[Explanation of symbols]

 F Shooting screen f1 to f5 Display index S1 to S5 Aggregate of small prisms Sf Fresnel lens S Focusing plate S2P Micro prism 1 Camera body 2 Mirror box 3 Camera mount-4 Shutter device 5 Image pickup surface 6 Main mirror 7 Submirror 8 Focus detection device 9 Focusing Plate 10 Penta Prism 11 Eyepiece 12 Photometric Lens 13 Photometric Sensor 15 Light Emitting Element 34 Eyepiece 36 Focusing Plate 40 Objective Lens

Claims (6)

[Claims] 1. A finder device for irradiating a plurality of display indices formed on a display panel with a light beam from an illuminating means and observing both a subject image formed on the display panel and the display indices. Each of the plurality of display indices of the plate has an aggregate of a plurality of micro prisms, and among them, some of the micro indices of the display indices are directed from the center of the display plate to any of the plurality of display indices. A finder device wherein the ridge direction of the micro prism is formed in a direction substantially parallel to the drawn straight line. 2. The display panel according to claim 1, further comprising a lens portion having a predetermined curvature in a predetermined region at a central portion, and a Fresnel lens comprising a plurality of continuous prisms concentrically extending in an outer peripheral region of the lens portion. The finder device according to claim 1, wherein the finder device is used. 3. The illumination means has an illuminating optical axis which is on a plane formed by a perpendicular line to the ridge direction of the micro prism of the display index and a normal line to the display plate, and which is parallel to the plane. The finder device according to claim 1, wherein the display index is illuminated with light. 4. An arbitrary display index out of a plurality of display indices provided on the display plate is parallel or perpendicular to a plane including an illumination optical axis of the illuminating means for illuminating the display index. 4. The finder device according to claim 1, wherein the finder device has a contour shape drawn in a direction substantially coincident with the direction. 5. The ridgeline direction of the ridgeline of the microlens of some of the display indices of the plurality of display indices is substantially perpendicular to the ridgeline direction of the ridge of the concentric prism of the Fresnel lens. 3. The finder device according to claim 2, wherein: 6. An optical apparatus comprising the finder device according to any one of claims 1 to 5.