JP3335007B2 - Camera viewfinder device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to a display device in a viewfinder of a single-lens reflex camera.

[0002]

2. Description of the Related Art Heretofore, as a display device in a viewfinder of a camera, it has been general to display exposure control information of the camera outside the viewfinder field. However, with the recent advancement of electronic cameras, the functions of the cameras have been rapidly developed.In particular, the information provided to the photographer at the time of shooting has been increasing due to the increase in the number of autofocus points and the sophistication of exposure control functions. is there. Therefore, in recent years, a camera that performs superimpose display in order to display various kinds of photographing information even in the viewfinder view has been proposed. For example, JP
As disclosed in JP-A-798826 and JP-A-6-148735, a display element such as a liquid crystal display element for performing transmissive display is disposed above a focusing screen in a finder optical path of a camera, and is superimposed on a subject image to obtain various kinds of photographing information. It is configured to display figures and characters, and the liquid crystal display element superimposes the display in the finder field of view,
The display that selectively displays information necessary for photographing and the auxiliary display of photographing such as a photometric range mark and a grid eye displayed on the focusing screen are configured to be overlapped.

[0003]

However, in the above-mentioned prior art, since the display member for superimposing and the focusing screen are separate bodies, the focusing screen is replaced in a camera having a replaceable focusing screen. At this time, the optical axis center of the superimposed display member and the focusing screen will be misaligned, and if it is replaced with a replacement focusing screen such as a focusing screen with a grid or a focusing screen with a graduation cross line, the grid line or the cruciform line with the graduation cross The display deviation from the imposed display becomes conspicuous, and the display in the viewfinder becomes very unsightly. In addition, it is extremely difficult to align the optical axis of the focusing screen with the superimposed display member, and it is necessary to integrally position and maintain it. Therefore, manufacturing errors in viewfinder optical systems and focusing screens due to environmental changes (temperature and humidity) It is extremely difficult to make the focusing screen replaceable, taking into account, for example, the case where the dimensional change occurs. In particular, it is almost impossible for a camera user to change the focusing screen, and for example, there is a disadvantage that the focusing screen must be changed at a service station or the like.

[0004]

According to the present invention, there is provided a first display member for performing a first superimposed display in a finder visual field, and the first display member in the finder visual field. A focusing screen (5) for displaying overlapped display, and a guide portion (50a.60a) for guiding the focusing screen when the focusing screen is mounted, and a finder optical system and the first display member. An optical system holding member (30) for positioning and holding, wherein the focusing screen is held by the optical system holding member when the focusing screen is exchanged and mounted, and the guide for guiding is provided. In the part, the center of the optical axis of the focusing screen is fine. As with slight clearance in a state of being located at the center of the over light axis is to have a guide adjusting means (60.61.31.32) for positioning the guide portion.

[0005] In the above-mentioned configuration, in a camera having a replaceable focusing screen, the position of a guide portion for guiding the focusing screen is adjusted by guide adjusting means, so that the first display member for superimposed display is provided. And the optical axis center of the focusing screen can be prevented from shifting, and the gap (play amount) between the focusing screen and the guide member can be adjusted to an appropriate play amount. It is possible to easily and reliably exchange the focusing screen even if the dimensions of the focusing screen change.

[0006]

1 to 15 are views showing the present invention, FIG. 1 is a view showing a section of an optical system in a camera of the present invention, and FIG. 2 is an enlarged sectional view of a finder optical system in FIG. is there. In FIG. 1, reference numeral 1 denotes a camera main body, and 2 denotes a semi-transmissive main mirror, which reflects and guides a photographic light beam transmitted through a not-shown photographic lens to a finder optical system, and partially transfers the photographic light beam to an automatic The light is transmitted for guiding to the focusing device 4. Reference numeral 3 denotes a total reflection type sub-mirror for guiding a part of the photographing light beam transmitted through the main mirror 2 to an automatic focus adjusting device 4 described later, 4 denotes an automatic focus adjusting device, and 5 denotes a photographing light beam reflected by the main mirror. A focusing screen (second display member in the present invention) for forming an image. The focusing screen 5 is detachable as will be described later, and a Fresnel lens 5a is formed on a lower surface and a focal image forming surface 5b is formed on an upper surface. The focus image plane 5b has a photometric range mark 5 described later.
c, a grid mark 510a, a scaled cross line 520a, and other display marks in the viewfinder visual field are engraved. Reference numeral 6 denotes a display panel for superimposing (a first display panel in the present invention; hereinafter, an SI display panel), and a plurality of small prisms formed on the lower surface 6a of the SI display panel 6 as described later. A range-finding range mark group 6d is displayed, and the illumination light of the SI-LED 11, which will be described later, is projected onto the range-finding range mark group 6d by the SI illumination lens 10, so that the range-finding range mark group 6d is placed in the range-finding range. It looks as if it is lit by the reflection of the minute prisms forming the mark group 6d. Reference numeral 7 denotes a condenser lens which condenses the light flux formed on the focal image forming surface 5b of the focusing screen 5 upward (an eyepiece optical system including a pentaprism). Reference numeral 8 denotes a penta roof prism, 9 denotes an eyepiece lens group incorporating a diopter correction adjustment mechanism (not shown), and includes a concave lens 9a, a convex lens 9b, and a flat protective glass 9c. The diopter is adjusted by moving it. Reference numeral 10 denotes an SI illumination lens for irradiating the SI display panel 6 with light of an SI-LED 11 for display illumination, and 11 denotes an SI-LED for display illumination of the SI display panel 6, and The distance measurement mark group 6d of the SI display panel 6 is illuminated. Reference numeral 12 denotes a photometric lens which re-images a subject image formed on the focal image forming surface 5b of the focusing screen 5 on a photometric sensor 13 described later. Reference numeral 13 denotes a photometric sensor that measures the light of a subject image formed by the photometric lens 12. The photometric sensor 13 is a multi-split photometric sensor in which a sensor light receiving unit (not shown) is divided into a plurality. 14a is a lower display device for displaying photographing information in the lower part of the finder field outside the finder field,
Further, as will be described later, a horizontal display device 14 for displaying photographing information to the side of the finder field outside the finder field.
b (see FIG. 4). Reference numeral 20 denotes a screen holding frame for holding the focusing screen 5, one end of which is rotatably supported about a hinge 20a as a rotation center, and the other end of which locks a lock claw 20b by a pressing spring 40 described later. Have been. Reference numeral 30 denotes a penta holder, which is an optical system holding member, which holds the SI display plate 6 in an exchangeable manner, holds the condenser lens 7 and the penta roof prism 8 inside thereof, and also includes the lower display member 14 and a lower display member described later. The pressing spring 40 is fixed.

FIG. 3 is a view A of the finder optical system shown in FIG.
FIG. 3 is a view as viewed from the front of the camera. In the figure, the holding spring 40 is made of a thin plate member having spring properties.
The holding frame lock arm 41 for locking the lock claw 20b of the screen holding frame 20 and the SI display plate 6
Lock arm portions 44a and 44 for locking the display panel
b. The holding frame lock arm 41 is provided with a lock hole 42 for engaging with the lock claw 20b, and a lock release knob 43 is provided at the tip of the holding frame lock arm 41. Then, the lock release knob 43 is pulled up in the direction of the paper surface in the drawing to deform the holding frame lock arm, thereby releasing the lock between the lock hole 42 and the lock claw 20b of the screen holding frame 20. As a result, the focusing screen 5 can be detached from the camera 1 and replaced. The display plate lock arm 44
Locking portions 45a, 4b for engaging with two display plate lock claws 6b of the SI display plate 6, which will be described later, are provided on the a and 44b.
5b, which are engaged with two display plate lock claws 6b of the SI display plate 6 to be described later.
The leading ends of a and 45b are bent in the L-shape toward the back side of the drawing. In the vicinity of the locking portions 45a and 45b, locking releasing portions 46a and 46b are provided, and the locking releasing portions 46a and 46b are lifted in the front direction of the paper surface to display the panel lock arms 44a and 44b. By deforming the locking portion 4
5a, 45b and the two display plate lock claws 6b of the SI display plate 6 are disengaged, and the camera 1 of the SI display plate 6 is disengaged.
It is possible to replace and remove from the server. In addition, the SI display plate 6
Is positioned on the penta holder 30 by fitting the display plate lock claw 6b with two positioning notches 33 provided on the penta holder 30.

FIGS. 4 and 5 show the SI display plate 6 and the focusing screen 5 for displaying images in the viewfinder view of the present invention. FIG. Lower side (the lower surface 6a of the SI display panel 6)
5 shows the focusing screen 5 when the camera 1 is viewed from above (the side of the focusing screen 5b of the focusing screen 5: see FIG. 1). It is. As shown in FIG. 4, a plurality of distance measurement range mark groups 6d formed by minute prisms are formed in the center of the lower surface 6a of the SI display plate 5,
The illumination light of the SI-LED 11 described above is projected onto the distance measurement range mark group 6d by the SI illumination lens 10, so that the distance measurement range mark group 6d is turned on by the reflection of the micro prism. Further, one side of the SI display plate in the longitudinal direction is engaged with the display plate lock arms 44a and 44b of the holding spring 40 fixed to the penta holder 30, pressed and pressed, and 3
The display plate lock claw 6b positioned on the penta holder 30 by fitting with two positioning notches 33 provided on the penta holder 30 and the penta holder 3 on the other side.
0 has a hinge claw 6c for engaging with the end face of the opening.

In FIG. 5, a photometric range mark 5c indicating the range of photometry by the photometric sensor 13 of the camera 1 is displayed on the imaging focal plane 5b of the focusing screen 5. 5d is the focusing screen 5 when attaching and detaching the focusing screen 5.
And is fixed in the longitudinal direction of the focusing screen 5 (the front surface of the camera 1 and the holding spring 40 side: see FIG. 1). Reference numeral 5e denotes a pressing projection for pressing the focusing screen 5 against the lower part of the penta holder 30 by the screen holding frame 20, and has a substantially arc shape toward the Fresnel lens 5a (back side of the paper surface) of the focusing screen 5. Projections are provided at both ends of the focusing screen 5, and the screen holding frame 20 is provided with the pressing projections 5e.
By pushing up, the focusing screen 5 is pressed against the lower part of the penta holder 30.

FIG. 6 shows the focusing screen 5.
And the state where the SI display plate 6 is attached to and detached from the penta holder 30. In the figure, when the lock release knob 43 of the holding spring 40 of the penta holder 30 is operated, the locking hole 42 of the holding spring 40 and the locking claw 20 b of the screen holding frame 20 are moved.
Is disengaged, and the screen holding frame 20 rotates counterclockwise around the hinge 20a while holding the focusing screen 40. In this state, the operating knob 5d of the focusing screen 5 shown in FIG. 5 is picked up with a tool such as tweezers and taken out of the screen holding frame 20 to exchange (attach / detach) the focusing screen 5. When the focusing screen 5 is removed, the SI display panel 6 can be attached and detached. Lock release part 45 of the pressing spring 40
a, 45 Tb is raised in front of the camera 1 (pulled up in the front direction of the paper surface in FIG. 3).
The engagement between the two display plate locking claws 6b and the locking portions 45a and 45b of the pressing spring 40 is released. When this state is maintained, the SI display plate 6 is disengaged from the penta holder 30 while rotating substantially in the counterclockwise direction about the hinge pawl 6c as the center of rotation (indicated by a two-dot broken line in the figure). The plate 6 can be replaced. However, in the present invention, the SI display plate 6 displays the function of the camera (in this embodiment, the position of the distance measuring point), and is usually configured so that the photographer (user) cannot exchange it. I have.

In the superimposed display of the camera of the present invention, the light reflection type superimposed display is performed as described above, but a liquid crystal display element or the like which performs the transmissive display as described in the conventional example is used. The display element may be arranged in the optical path of the viewfinder of the camera, and may display a figure or a character on the subject image.

FIG. 7 shows a square-eye screen 510 and a scaled cross-hair screen 520, which are replacement focusing screens of the focusing screen 5 in the finder optical system. The gridded screen 510 is the focusing screen 5.
In addition to the photometric range mark 5c, a grid 510a is added to the image forming focal plane 5b, and the scaled crosshair screen is moved to the image forming focal plane 5b of the focusing screen 5 by Since a scaled cross line 520a and a peripheral scale 520b are added in addition to the photometric range mark 5c, the other functions and shapes are the same as those of the focusing screen 5.

FIGS. 8 to 11 show a guide member 50 of the focusing screen 5 which is a display guide means of the present invention.
And an adjustment guide member 60 which is a display guide adjustment means. 8 is a cross-sectional view (cross-section CC in FIG. 9) of the finder optical system shown in FIGS. 1 and 2 along the finder optical axis in the front-rear direction of the camera.
FIG. 3 is a view of the finder optical system shown in FIG. 2 as viewed from below, in which a two-dot broken line indicates the screen holding frame 20;
Is shown. FIG. 10 shows the guide member 5 in FIG.
0 is an enlarged view, and FIG. 11 is a side sectional view (section BB) of the display guide means including the adjustment guide member 60 in FIG.
It is. In each of the drawings, the guide member 50 of the focusing screen 5 is formed of a thin plate having spring properties as described above, and has an upper end fixed to the side surface of the penta holder 30 and a lower end A guide portion 50a bent in a V shape is provided. An adjustment guide member 60 for guiding the focusing screen 5 and adjusting the position of the focusing screen 5 is formed in a L-shape by a thin plate having a spring property. It is pressed against the side. The adjustment guide member 60 has a positioning hole 60d and a restriction hole 60e respectively fitted to the positioning pin 31 and the restriction pin 32 provided on the back side of the mounting portion 30a of the horizontal display device 14b of the penta holder 30. The positioning pin 31 is rotatably held about a rotation center by an eccentricity adjusting dowel 61 described later. The adjustment guide member 60 has an adjustment guide portion 60a drawn in a substantially arc shape at a lower end portion thereof, and a projection pressed against the side surface of the penta holder 30 by a spring force near the upper side of the adjustment guide member 60. Patch 6
0b is formed. Reference numeral 60c denotes an approximately oval-shaped adjustment hole which is fitted with an eccentricity adjusting portion 61c of the eccentricity adjusting dowel 61 described later. Numeral 61 denotes an eccentricity adjusting dowel, as shown in FIG.
0 is sandwiched by the washer 62 and the caulking foot 61b
Is caulked to the washer 62 so that the eccentricity adjusting dowel 61 is rotatably held. Reference numeral 61a denotes a dowel adjusting portion having a cross-shaped slot for rotating the eccentricity adjusting dowel 61, and 61b denotes the above-described caulking foot portion. 61c is an eccentricity adjusting portion, which has a cylindrical shape having a center at a position shifted with respect to the rotation center of the eccentricity adjusting dowel 61,
As described above, the adjustment hole 6 of the adjustment guide member 60 is used.
0c, when the eccentricity adjusting dowel 61 is rotated, the eccentricity adjusting portion 61c
The adjustment guide member 60 is eccentrically slid in the zero adjustment hole 60c, and the adjustment guide member 60 is rotated about the positioning pin 31 as a rotation center.

FIGS. 12 to 15 show enlarged operation views of the adjustment guide member in FIGS. When the eccentricity adjustment dowel 61 of the adjustment guide member 60 is rotated in the counterclockwise direction, the adjustment guide member 60 is turned around the positioning pin 31 of the penta holder 30 as shown in FIGS. Rotate clockwise. As the adjustment guide member 60 rotates in the counterclockwise direction, the substantially arc-shaped drawn adjustment guide portion 60a formed at the lower end of the adjustment guide member 60 becomes the abutting portion 60b.
Is moved in a direction in which a gap is opened with respect to the focusing screen 5 (see FIG. 12). When the eccentricity adjustment dowel 61 of the adjustment guide member 60 is rotated clockwise, the adjustment guide member 60 is rotated around the positioning pin 31 of the penta holder 30 as shown in FIGS. Rotate clockwise. As the adjustment guide member 60 rotates clockwise, the substantially arc-shaped drawn adjustment guide portion 60a formed at the lower end of the adjustment guide member 60 is formed of a thin plate having spring properties. And the pressing force is applied to the side surface of the penta holder 30 by the spring force.
Moves in the direction in which the gap is closed (the direction in which the focusing screen 5 is pressed) (see FIG. 14). In this way, by rotating the eccentricity adjusting dowel 61, the gap between the adjusting guide portion 60a of the adjusting guide member 60 and the focusing screen 5 is adjusted.

The guide member 50 has a small gap between the focusing screen 5 and the guide portion 50a (a contact portion with the focusing screen 5) when the focusing screen 5 is located at the center of the finder optical axis. (About 0.03 mm) and fixed to the penta holder 30. Further, in the above-described state, the adjustment guide portion 60a of the adjustment guide member 60 has a play amount of the focusing screen 5 of about 0.08 mm (a gap of the guide portion 50a of 0.03 mm + the adjustment guide portion 60a).
Adjustment is made so that the gap adjustment amount a is 0.05 mm).
This is because, since the focusing screen 5 is made of an acrylic material, expansion and contraction of about 50 μm can be considered due to changes in temperature and humidity (particularly at high humidity).
For example, even if the focusing screen 5 expands by about 50 μm due to humidity, the focusing screen 5 is not pinched by the guide member 50a and the adjustment guide member 60a, and is set so that the focusing screen 5 can be smoothly attached and detached even when the focusing screen 5 is replaced. The amount of rattling.

As described above, it is assumed that the SI display panel 6 cannot be replaced by a photographer (user). For this reason, the SI display panel 6 is pressed against the penta holder 30 in the front-rear direction of the camera by the pressing spring 40 toward the hinge portion 20a of the screen holding frame 20 of the penta holder 30, and also in the camera left-right direction. Because it is positioned with a very small gap,
The amount of deviation of the center of the SI display plate 6 from the center of the finder optical axis can be suppressed with an extremely small amount. However, usually, the focusing screen 5 shown in FIG.
As shown in (1), the photographer (user) is configured to be able to exchange. In such a configuration, the focusing screen 5 is connected to the screen holding frame 2.
In order to improve the attachment / detachment operability with respect to 0, a certain amount of gap is set and held. For example, assuming that the focusing screen 5 is attached and detached without the guide member 50 and the adjustment guide member 60,
The focusing screen 5 is mounted on the screen holding frame 2.
A displacement occurs between the finder optical axis (or the center of the SI display panel 6) and the center of the focusing screen 5 by the amount of the gap set to 0. In particular, when the squared screen 510a or the scaled cross-hair screen 520a, which is an exchangeable focusing screen as shown in FIG. 7, is replaced and mounted, the mounting displacement between the SI display panel 6 and the focusing screen 5 appears remarkably. .

According to the present invention, when the focusing screen 5 is mounted as shown in FIG. 6, the mounting displacement of the focusing screen 5 in the front-rear direction of the camera is performed by setting the focusing screen 5 on the screen holding frame 20; When the focusing screen 5 is pushed upward while being pressed against the hinge portion 20a side of the screen holding frame 20 at the time of being pushed up and set on the penta holder 30, the play of the focusing screen 5 in the front-rear direction is reduced. Are offset and it is possible to easily reduce the amount to a very small amount.

The mounting displacement of the focusing screen 5 in the left-right direction of the camera, as the focusing screen 5 is pushed up to the penta holder 30 while rotating as shown in FIG.
A guide portion 50a bent at the lower end of the guide guide 50a and an adjustment guide 60 formed at the lower end of the adjustment guide member 60 and drawn in a substantially arc shape.
The end surface of the focusing screen 5 is gradually guided by a, and the focusing screen 5 is mounted while being positioned with respect to the finder optical axis (or the SI display panel 6). In a state where the focusing screen 5 is mounted on the penta holder 30, the focusing screen 5 is moved by the screen holding frame 20.
Since the pressing screen 5 is pressed against the penta holder 30, the focusing screen 5 does not shift after mounting.

[0019]

As described above, according to the present invention, the first display member (6) for performing the first superimposed display in the finder visual field and the first display member in the finder visual field are provided. A focusing screen (5) for displaying overlapped display, and a guide portion (50a.60a) for guiding the focusing screen when the focusing screen is mounted, and a finder optical system and the first display member. An optical system holding member (30) for positioning and holding, wherein the focusing screen is held by the optical system holding member when the focusing screen is exchanged and mounted. The center of the optical axis of the focusing screen is And a guide adjusting means (60.61.31.32) for adjusting the position of the guide portion so as to have a slight gap in a state of being positioned at the center of the optical axis of the superimposed display. Of the display member and the center of the optical axis (display) of the focusing screen can be prevented from shifting between the superimposed display and the display on the focusing screen.

Further, the guide member of the focusing screen guides as the focusing screen is mounted and set, and the position of the focusing screen is adjusted so that the gap (play amount) between the focusing screen and the guide member is adjusted to an appropriate play amount. It can be adjusted, and even if the size of the focusing screen changes due to temperature, humidity, etc., it is possible to easily and reliably adjust the display deviation between the superimposed display and the display on the focusing screen, and easily replace the focusing screen Is made possible, the user can exchange the focusing screen.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical system of a camera according to the present invention.

FIG. 2 is an enlarged sectional view of the finder optical system of FIG. 1;

FIG. 3 is a front view of the finder optical system shown in FIG.

FIG. 4 is a diagram for explaining an SI display panel for performing superimposed display according to the present invention.

FIG. 5 is a diagram illustrating a focusing screen of the present invention.

FIG. 6 is a diagram for explaining attachment / detachment of the SI display plate and the focusing screen.

FIG. 7 is a diagram illustrating an exchange focusing screen of the present invention.

8 is a cross-sectional view of the finder optical system of FIG. 2 in the front-rear direction of the camera along the finder optical axis (cross-section CC of FIG. 9).

9 is a view of the finder optical system of FIG. 2 viewed from below the camera.

FIG. 10 is an enlarged sectional view of a guide member according to the present invention.

11 is a side sectional view of the adjustment guide member of the present invention (FIG. 9).
Section BB)

FIG. 12 is a diagram illustrating the operation of the adjustment guide according to the present invention in an enlarged sectional view.

FIG. 13 is a diagram for explaining the operation of the adjustment guide according to the present invention in an enlarged sectional view.

FIG. 14 is a diagram for explaining the operation of the adjustment guide according to the present invention in an enlarged sectional view.

FIG. 15 is a diagram illustrating the operation of the adjustment guide according to the present invention in an enlarged sectional view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Camera main body 2 Main mirror 3 Sub-mirror 4 Automatic focusing device 5 Focusing screen 6 SI display board 7 Condenser lens 8 Penta holder 9 Eyepiece lens group 10 SI illumination lens 11 SI-LED 12 Photometric lens 13 Photometric sensor 14a Viewfinder lower display device 14b Viewfinder horizontal display device 20 Screen holding frame 30 Penta holder 40 Pressing spring 50 Guide member 60 Adjustment guide member 510 Focusing screen with squares 520 Crosshair focusing screen with scales

Continuation of front page (58) Fields investigated (Int.Cl. ⁷ , DB name) G03B 17/20 G03B 13/00-13/28

Claims (1)

(57) [Claims] 1. A first super-display in a finder field of view.
A first display member for displaying an imposed display;
Overlap display with the first display in the field of view
Focusing screen for performing
When installing the focusing screen,
A guide section for guiding cleanliness
Positioning and holding the inner optical system and the first display member
An optical system holding member, and the focusing screw
When replacing the focus
A camera camera for holding the lean on the optical system holding member.
A guide unit for guiding,
The center of the optical axis of the focusing screen is the viewfinder light
So that there is a slight gap in the center of the shaft,
Guide adjusting means for adjusting the position of the guide section.
A viewfinder device for a camera.