JPH09189961A - Mirror device and camera using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily facilitate processing and to improve machining accuracy by forming the mount surface of a semitransmissive mirror and an abutting surface on a positioning member on either the surface side or the back surface side of a mirror holding frame. SOLUTION: The mirror holding frame 4 is formed to have an upper surface part 4a facing to reflected light 17b and a flange part extended to a side facing to transmitted light 17d from the edge of the upper surface part. The outer periphery part of a half mirror 3 is stuck to the back surface side 4b of the upper surface part 4a. The lower surfaces(abutting surface) 4c and 4d of the flange part of the frame 4 are allowed to abut on the upper surfaces of positioning members 15a and 15b so as to be located at positions where the mirror 3 is obliquely provided in a photographing optical path. Since the sticking surface 4b and the abutting surfaces 4c and 4d are formed on the back surface side of the frame 4, the surfaces 4b to 4d are simultaneously processed. Then, production cost is reduced by the reduction of the number of working stages.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mirror device used in a camera or the like.

[0002]

2. Description of the Related Art A semi-transmissive mirror (half mirror) obliquely installed in a photographing optical path of a camera transmits a part of a light beam emitted from a photographing lens and reflects the rest.

Here, FIG. 3 shows a conventional mirror device. In this mirror device, the semi-transmissive thin film mirror 103
Are bonded and fixed to the upper surface of the mirror holding frame 102. The mirror holding frame 102 is biased to the lower right in the figure by a leaf spring 101b attached to the mirror pressing frame 101, and is obliquely provided at a predetermined position in the photographing optical path by contacting the positioning members 100a and 100b. It

The reflected light 106b generated by the light emitted from the lens 106a being reflected by the semi-transmissive thin film mirror 103 is guided to a moving image pickup system (not shown). Further, the transmitted light 106 a generated by the emitted light 106 a being transmitted through the semi-transmissive thin film mirror 103.
c is guided to the focus detection system by the sub-mirror 104 obliquely provided in the transmission optical path, or used for exposing the silver salt film (still image shooting) by retracting the sub-mirror 104 from the transmission optical path.

[0005]

However, in the conventional mirror device shown in FIG. 3, the adhesive surface 102a of the mirror 103 in the mirror holding frame 102 and the mirror holding frame 10 are arranged.
The contact surfaces 102b and 102c for the positioning members 100a and 100b in 2 are separately formed on the front surface and the back surface of the mirror holding frame 102. Therefore, in processing the mirror holding frame 102, in order to finish the adhesive surface 102a and the contact surfaces 102b and 102c with high accuracy, first, chucking is performed to finish the front surface side, and then the mirror holding frame 102 is inverted. It will be necessary to re-chuck it and finish the back side. Moreover, by re-chucking the mirror holding frame 102, the relative dimensional accuracy between the adhesive surface 102a and the contact surfaces 102b, 102c is likely to decrease.

Further, in the mirror device of FIG. 3, the mirror 1
Since the flatness of the part on the adhesive surface 102a in 03 is deteriorated, so-called ghost may be generated on the reflection side. Therefore, in order to shield the adhesive surface 102a from light, the mirror pressing frame 101 needs to have a light shielding function. In other words, it is necessary to provide a member different from the mirror holding frame 102 in order to shield the adhesive surface 102a from light.

Moreover, in the mirror device shown in FIG.
Since 01b urges and presses the mirror holding frame 102 via the mirror 103, the urging force may distort the mirror 103 and deteriorate the flatness. The leaf spring 10
It is possible to directly press the outside of the mirror 103 on the surface of the holding frame 102 by 1b, but this causes a problem that the holding frame 102 becomes large.

Therefore, a first object of the present invention is to provide a mirror device which facilitates the processing of the bonding surface (mounting surface) and the contact surface and can improve the processing accuracy of these. It is in.

A second object of the present invention is to provide a mirror device capable of eliminating the need for a special member for shielding the adhesive surface and the like from light.

A third object of the present invention is to distort the mirror and increase the size of the holding frame,
An object of the present invention is to provide a mirror device in which a holding frame can be urged and brought into contact with a positioning member.

[0011]

In order to achieve the above object, in the first invention of the present application, a mirror holding frame to which a semi-transmissive mirror is attached is brought into contact with a positioning member, and the semi-transmissive mirror is used as a photographing optical path. In the mirror device disposed inside, both the mounting surface of the semi-transmissive mirror and the contact surface of the positioning member in the mirror holding frame are formed on one of the front side and the back side of the mirror holding frame.

That is, by laying out the mounting surface (adhesive surface) and the contact surface on the same side of the holding frame, it is only necessary to perform chucking once at the time of processing, and re-chucking as in the conventional case. It is intended to prevent a decrease in processing accuracy due to this.

In the second aspect of the present invention, the mirror holding frame is formed with a light shielding portion for blocking the incidence of the photographing light beam on the mounting surface and the end of the semi-transmissive mirror, and is a member different from the conventional holding frame. Eliminates the need to prevent reflected light ghosts.

Further, in the third invention of the present application, when the mirror holding frame has an urging means for urging the mirror holding frame against the positioning member, the urging means is the other of the front side and the back side of the mirror holding frame. That is, the contact portion of the biasing means can be secured without contacting the mirror mounting surface with the holding frame without increasing the size of the holding frame and the action of the biasing force on the mirror itself can be avoided. It is desirable to do.

It is desirable to provide the camera with the mirror device as described above so as to improve not only the image quality of a still image captured by transmitted light but also the image quality of a moving image captured by reflected light.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) An embodiment of the present invention will be described below with reference to the drawings. First, FIG. 2 shows the structure of a compound camera including a mirror box (mirror device) according to the first embodiment of the present invention. In this figure, 1
Is a photographing lens, and the luminous flux (emitted light) 17a that has passed through the photographing lens 1 is emitted into the mirror box.
The light enters the half mirror 3 obliquely arranged with respect to 7a, a part of the light is guided to the field lenses 5a and 5b as reflected light 17b, and the rest is guided to the focus detection system as transmitted light 17d.

The reflected light 17b incident on the field lenses 5a and 5b is reflected by the total reflection mirror 18 (17
c), enters the reduction lens 6. The reduction lens 6 reduces the aerial image formed near the field lenses 5a and 5b by the taking lens 1 on the light receiving surface of the CCD 9 and re-images it. A video signal corresponding to the image on the light receiving surface is output from the CCD 9, and the video signal is recorded on a video tape (not shown). In this way, moving image shooting using the reflected light 17b of the half mirror 3 can be performed.

On the other hand, the transmitted light 17d guided to the focus detection system
Is reflected by the sub-mirror 10 obliquely provided in the transmission optical path (17e) and guided to the focus detection device 14. The focus detection device 14 outputs a signal necessary for adjusting the focus of the taking lens 1 using the transmitted light 17d.

Here, the sub-mirror 10 can be retracted from the transmitted light path by a drive mechanism (not shown), and when the sub-mirror 10 is retracted from the transmitted light path, the transmitted light 17d travels backward, that is, toward the shutter device 16. . Therefore, if the shutter device 16 is operated, the transmitted light 17
It is possible to perform exposure of a silver salt film (not shown) arranged behind the shutter device 16 by d, that is, still image shooting.

Next, the structure of the mirror box is shown in FIG.
This will be described in detail with reference to FIG. In this figure, 3 is a half mirror, and this half mirror 3 is formed by vapor deposition forming a semi-transmissive reflective film on the surface of a thin glass substrate.

Reference numeral 4 denotes a mirror holding frame, which has an upper surface portion 4a facing the reflected light 17b and a flange portion extending from the edge of the upper surface portion to the side facing the transmitted light 17d. Has been formed. The outer peripheral portion of the half mirror 3 is adhered to the rear surface side (the side facing the transmitted light 17d) 4b of the upper surface portion 4a. Note that, hereinafter, the rear surface side of the upper surface portion 4a is referred to as an adhesive surface.

Thus, the adhesive surface 4b and the outer end of the half mirror 3 are covered with the mirror holding frame 4,
Emitted light 17a and reflected light 17b for these portions
Since the incidence of light is blocked, it is not necessary to provide the light blocking member 101 for ghost prevention other than the holding frame 102 as in the conventional example shown in FIG. 3, and the cost can be reduced accordingly. .

Numerals 15a and 15b are positioning members provided in the mirror box. And the mirror holding frame 4
The lower surface (contact surface) 4c, 4d of the flange portion is brought into contact with the upper surfaces of the positioning members 15a, 15b, respectively, whereby the half mirror 3 is positioned at a position obliquely provided in the photographing optical path.

Here, the adhesive surface 4b and the contact surface 4
Since both c and 4d are formed on the back surface side of the mirror holding frame 4, there is no need to reverse or chuck the mirror holding frame 4 when processing the adhesive surface 4b and the contact surfaces 4c and 4d. It is also possible to process both surfaces 4b, 4c, 4d at the same time. Therefore, the manufacturing cost can be reduced by the number of working steps, and the double-sided
The processing accuracy of b, 4c, and 4d can be improved.

Reference numeral 20 is a positioning member 15 for positioning the mirror holding frame 4.
a leaf spring that urges in the direction of abutting against a and 15b,
The leaf spring 20 contacts the surface side (the side facing the reflected light 17b) of the upper surface portion 4a of the mirror holding frame 4 and directly presses the mirror holding frame 4. Therefore, the biasing force of the leaf spring 20 does not act on the half mirror 3 itself, and the flatness of the half mirror 3 is not impaired by this biasing force. Therefore, not only the image quality of still image shooting with the transmitted light 17d but also the image quality of moving image shooting with the reflected light 17b can be improved.

In the above embodiment, the compound camera for photographing a moving image by the reflected light of the half mirror has been described, but the present invention is not limited to such a compound camera, and a single lens reflex camera, a lens shutter camera, a video camera, etc. ,
The present invention can be applied to various forms of cameras, optical devices other than cameras, and other devices, and devices applied to those cameras, optical devices, and other devices, or components constituting these devices.

(Relationship Between Embodiment and Claims) In the above embodiment, the half mirror 3 is a semi-transmissive mirror in the claims, and the mirror holding frame 4 is a mirror holding frame in the claims. The adhesive surface 4b of the frame 4 is a mounting surface in the claims, the contact surfaces 4c and 4d are contact surfaces in the claims, and the upper surface portion 4a and the flange portion are light-shielding parts in the claims. The positioning members 15a and 15b correspond to the positioning members in the claims.

The above is the correspondence relationship between each configuration of the present invention and each configuration of the embodiment, but the present invention is not limited to the configuration of these embodiments, and the mechanism or the embodiment described in the claims is not limited thereto. Any structure may be used as long as the function of the structure can be achieved.

[0029]

As described above, in the first invention of the present application, the mirror mounting surface (bonding surface) of the mirror holding frame and the contact surface of the positioning member are laid out on the same side of the holding frame. Therefore, according to the present invention, the mounting surface and the contact surface can be processed only by performing chucking once when the holding frame is processed, which reduces the number of work steps required by re-chucking as in the conventional case. It is possible to prevent an increase and a reduction in processing accuracy due to the increase.

Further, in the second aspect of the present invention, the mirror holding frame is formed with the light-shielding portion for blocking the incidence of the photographing light beam on the end surface of the mounting surface and the semi-transmissive mirror, which are the generation sources of the reflected light ghost. Therefore, according to the present invention, it is possible to eliminate the need to cover the mounting surface and the mirror end portion by using a member different from the holding frame as in the conventional case, and it is possible to reduce the number of parts, which reduces the manufacturing cost. It is possible to reduce.

Further, in the third invention of the present application, the biasing means for biasing the mirror holding frame in the direction of contacting the positioning member is brought into contact with the side of the mirror holding frame opposite to the mirror mounting surface. There is. Therefore, according to the present invention, the contact portion of the biasing means can be secured without increasing the size of the holding frame, and the flatness of the mirror is reduced by avoiding the action of the biasing force on the mirror itself. Can be prevented.

If the camera is equipped with the mirror device as described above, it is possible to improve not only the image quality of a still image captured by transmitted light but also the image quality of a moving image captured by reflected light.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a mirror device that is a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a compound camera including the mirror device.

FIG. 3 is a sectional view of a conventional mirror device.

[Explanation of symbols]

 1 Photographic lens 3,103 Half mirror 4,102 Mirror holding frame 4b, 102a Adhesive surface 4c, 4d, 102b, 102c Contact surface 9 CCD 10 Sub-mirror 14 Focus detection device 15a, 15b Positioning member 16 Shutter device 20, 101b Leaf spring

Claims (6)

[Claims] 1. A mirror device in which a mirror holding frame to which a semi-transmissive mirror is attached is brought into contact with a positioning member to dispose the semi-transmissive mirror in a photographing optical path. A mirror device, wherein both the mounting surface and the contact surface of the positioning member are formed on one of the front side and the back side of the mirror holding frame. 2. The mirror device according to claim 1, wherein the mirror holding frame is formed with a light shielding portion that blocks incidence of a photographing light beam on the mounting surface and an end portion of the semi-transmissive mirror. 3. An urging means for urging the mirror holding frame in a direction of abutting the positioning member, wherein the urging means contacts the other of the front side and the back side of the mirror holding frame. The mirror device according to claim 1, wherein the mirror device is a mirror device. 4. A camera comprising the mirror device according to claim 1. Description: 5. The camera according to claim 4, wherein one of the reflected light and the transmitted light of the semi-transmissive mirror shoots a moving image and the other shoots a still image. 6. The focus detection for photographing is performed by the reflected light or the transmitted light of the semi-transmissive mirror.
Or the camera according to 5.