JPH01321781A - Still video mechanism incorporating structure in film camera - Google Patents

Abstract

PURPOSE:To decrease the projection at the rear side of a camera by incorporating a relay lens of a still video mechanism so as to be arranged projectingly from an image forming face toward the photographing lens to a film camera and forming an optical picture from the photographing lens onto an image pickup element. CONSTITUTION:A relay lens 7 of a still video mechanism 6 incorporated in the film camera 1 is arranged projectingly more than a loading reference face of a main body 14 of the still video mechanism 6 with respect to the film camera 1. Thus, when the still video mechanism 6 is incorporated to the film camera 1, the relay lens 7 is arranged projectingly in an approaching direction toward the photographing lens 2 than the image forming face 2a. Thus, the projection toward the rear side of the camera is decreased by the share. With the projection at the rear side of the camera decreased in this way, then it is not required to provide a relay lens for the optical finder 3 to the sill video mechanism 6 and no eye point is moved.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a still video mechanism built-in structure in a film camera, and more specifically, a still video mechanism is built into an ordinary film camera so that still video shooting can be performed using a common photographic lens. It's about what's possible.

<Prior art> In recent years, in place of so-called film cameras that record optical images by exposing conventional silver halide film, optical images from a subject are converted into electrical image signals by an image sensor, and these electrical image signals are A still video camera has been developed that is configured to store information in a memory such as a magnetic disk, which corresponds to film, and the electrical image signals stored in the memory can be played back and viewed on a monitor, or printed out using a printing device. (Japanese Unexamined Patent Publication No. 59-18358)
(See Publication No. 2, etc.)

This kind of still video camera is a still video only machine, l! l;Although there are some advanced ones, since the optical system (taking lens) of a conventional film camera can be used for still video, the back cover for loading the film of the film camera can be removed and the still video mechanism (still video mechanism) can be used instead. There are some that allow you to attach a video pack.

An example of incorporating a still video mechanism into such a film camera is shown in FIG. Here, the film camera 1 is a so-called twin-lens reflex camera, and has a photographic lens 2.
It is equipped with an optical finder 3 independent of the system, and a film rail surface 5 is set so that the film is loaded onto the film imaging surface 2a of the photographing lens 2 to which a shutter (lens shutter) 4 is attached. There is. The silver halide film is pressed against the film rail surface 5 by a pressure roller elastically biased and supported by an M lid (not shown), and is pressed onto the image forming surface 2.
It is positioned and installed at point a.

The back cover of the film camera 1 is configured to be detachable,
In the figure, a still video mechanism 6 is attached in place of the back cover. The still video mechanism 6 includes a relay lens 7 and an image sensor 8 disposed at a predetermined position behind the relay lens 7.
The main components are various driver circuits, A/D converters, recording circuits, magnetic disk drive circuits, etc.

The relay lens 7 is disposed on the same optical axis as the photographing lens 2, and prevents the deviation between the film imaging surface 2a formed by the photographing lens 2 and the arrangement position of the image sensor 8, as well as the light receiving area of the film and the light reception of the image sensor 8. An optical image is formed on the light-receiving surface of the image sensor 8 by correcting the difference in area, and in the example shown in FIG. 5, the front end of the relay lens 7 is arranged behind the image-forming surface 2a. ing.

<Problems to be Solved by the Invention> By the way, when the still video mechanism 6 is attached instead of the back cover of the film camera 1 as described above, the thickness of the still video mechanism 6 is smaller than when used as the film camera 1. It is unavoidable that it protrudes to the rear. For this reason, the position of the eyepiece of the optical viewfinder 3 in the film camera 1 is recessed by the protrusion of the still video mechanism 6, making it difficult to look into the optical viewfinder 3, as shown in FIG. As such, it is necessary to provide a relay lens 9 for the optical finder 3 system on the still video mechanism 6 side, and to move the eye point backward so that the optical finder 3 can be viewed from the rear end surface of the still video mechanism 6.

In particular, in the case of an interchangeable lens single-lens reflex camera equipped with a focal plane shutter 10 as shown in FIG.
In order to enable the focal plane shutter 10 to open and close, it is necessary to arrange the relay lens 7 behind the focal plane shutter 10, and the arrangement of the relay lens 7 is restricted, and the relay lens 7 and the image sensor 8 The distance from the camera to the still video mechanism 6 has a large effect on the thickness of the still video mechanism 6, which makes it difficult to reduce the protrusion caused by the still video mechanism 6, and the large protrusion requires the eye point to be moved significantly backwards. Ta.

In FIG. 6, 11 is a pentaprism for a finder, and 12 is a quick return mirror disposed on the optical axis of the photographing lens 2 to refract an optical image toward the pentaprism 11.

The present invention has been made in view of the above-mentioned problems, and when a still video mechanism is incorporated into a film camera, the protrusion of the still video mechanism can be minimized to make the camera more compact, and the camera can be made more compact. It is an object of the present invention to provide a built-in structure for a still video mechanism that can avoid point movement.

<Means for Solving the Problems> Therefore, the present invention has a structure in which a still video mechanism is detachably incorporated into a film camera configured such that a photographic film is attached to the imaging surface of a photographic lens, and a relay A still video mechanism including a lens and an image sensor provided integrally with the relay lens is mounted on a film camera such that the relay lens is disposed so as to protrude toward the photographing lens side beyond the image forming surface. It is configured such that an optical image from the photographing lens is formed on the image sensor via the relay lens.

Further, the focal plane shutter provided in the film camera is configured to maintain an open state when the still video mechanism is installed.

According to this configuration, since the relay lens of the still video mechanism is incorporated so as to protrude toward the photographing lens side beyond the image forming surface (film image forming surface) of the photographing lens, which is the film mounting surface, the relay lens The image sensor installed on the rear side is also placed closer to the photographic lens, and as a result, the protrusion of the still video mechanism on the rear side of the camera can be reduced in accordance with the amount of protrusion of the relay lens from the imaging plane. It is possible to do so.

Furthermore, in a film camera equipped with a focal plane shutter, if the focal plane shutter is kept open when a still video mechanism is installed, it is possible to have the relay lens protrude closer to the photographing lens than the focal plane shutter. Even if a focal plane shutter is provided,
This avoids restricting the placement position of the relay lens, and allows the relay lens to be placed closer to the photographic lens.

<Example> Examples of the present invention will be described below based on the drawings. still,
The same elements as those in the conventional example shown in FIGS. 5 and 6 are given the same reference numerals.

The film camera l shown in FIG. 1 has a still video mechanism 6 built into its back cover, and in this state, an optical image passing through the photographing lens 2 is received by the image sensor 8 via the relay lens 7. An image is formed on the surface, and the image sensor 8 converts this optical image into an electrical image signal, which functions as a still video that is stored in a memory such as a magnetic disk. .

As shown in FIG. 2, the film camera l in which the still video mechanism 6 is not incorporated is a so-called lens shutter camera equipped with an optical viewfinder 3 independent of the photographic lens 2, and the photographic lens 2 and the shutter (lens The optical image that has passed through the shutter) 4 is formed on an image forming surface 2a set on a film rail surface 5, and the optical image is placed on a silver halide film (not shown) which is pressed against the rail surface 5 by a pressure plate 13 and positioned. An image is formed and a silver halide film is exposed and photographed, and the back cover on which the pressure plate 13 is supported is configured to be detachable.

Further, as shown in FIG. 3, the still video mechanism 6 incorporated in the film camera 1 includes a main body 14 mounted in place of the back cover of the film camera 1, and a relay lens 7 and a rear part of the relay lens 7. It is equipped with an image sensor 8 disposed at a predetermined position on the side, and various driver circuits, A
/D converter, recording circuit, magnetic disk drive circuit, etc.

Here, the relay lens 7 is disposed so as to protrude beyond the mounting reference plane of the main body 14 of the still video mechanism 6 (the part mounted in place of the back cover of the film camera 1) with respect to the film camera 1. Therefore, when the still video mechanism 6 is incorporated into the film camera 1, the relay lens 7 is arranged to protrude in a direction closer to the photographic lens 2 than the image forming plane 2a, as shown in FIG.

That is, when the still video mechanism 6 is not installed to take pictures on silver halide film, the image forming surface 2a and the photographing lens 2
There is an empty space between the first surface (rear end surface) of
If the image sensor 8 is brought closer to the photographic lens 2, the protrusion toward the rear of the camera can be reduced accordingly. Furthermore, if the amount of rearward protrusion of the camera is reduced, it will be easier to directly look through the optical finder 3 provided in the film camera 1 and take pictures, and a relay lens for the optical finder 3 will be provided in the still video mechanism 6. There is no need and the eye point does not move. The two-dot chain line in FIG. 1 indicates the movement position of the rear protrusion and the eye point when the relay lens 7 is disposed behind the imaging plane 2a.

In addition, as shown in FIG. 1, the relay lens 7 and the image sensor 8
The flange portion 14a, which is enlarged in diameter from the housing portion of the relay lens 7 of the box integrally supported, is brought into contact with the film rail surface 5 for positioning. In addition, the relay lens 7 has a function of adjusting the angle of view between that of the silver halide film and the angle of view between the silver halide film and the still video. be able to.

As described above, images can be recorded on a still video while utilizing the exposure mechanism 9 and focusing mechanism of the film camera 1 shown in FIG. 2. In addition, inside the viewfinder 3, there is an in-finder display that normally displays exposure information and focus status information, and information on still video usage status is also displayed on this display in addition to this display. This configuration further improves usability.

A second embodiment shown in FIG. 4 shows an embodiment in which a still video mechanism 6 is incorporated into a film camera 1 which is a single-lens reflex camera with interchangeable lenses.

In this case, the film camera 1 is equipped with a focal plane shutter 10 near the front of the imaging plane 2a on the camera body side in order to avoid film exposure when changing lenses, and a quick return lens that refracts the optical image toward the pentaprism 11. A mirror 12 is provided. The focal plane shutter 10 and the quick return mirror 1
2 allows the optical image to pass through the film imaging surface 2a only when the shutter button is used as a trigger.

Therefore, normally it is not possible to arrange the relay lens 7 of the still video mechanism 6 on the side closer to the shadow lens 2 than the focal plane shutter 10, but in this embodiment, when the still video mechanism 6 is installed, the focal plane It is configured to maintain the plane shutter 10 in an open state, and the quick return mirror 12 is pushed away by the outer periphery of the tip of the relay lens 7.

That is, when the still video mechanism 6 is assembled into the film camera 1, the switch 15 provided on the film camera 1 side
is pressed by a protrusion 16 provided on the side of the still video mechanism 6, so that installation of the still video mechanism 6 is detected midway through, and the focal plane is closed before the tip of the relay lens 7 reaches the focal plane shutter 10. The shutter 10 is retracted to allow insertion of the relay lens 7. Then, when the outer circumference of the tip of the relay lens 7 comes into contact with the quick return mirror 12 after passing through the focal plane shutter 10 maintained in an open state, the quick return mirror 12 is pushed up by the relay lens 7, and the quick return mirror 12 is pushed up by the relay lens 7. maintains a state parallel to the optical axis of the shadow lens 2.

Note that the retraction of the focal plane shutter lO due to the incorporation of the still video mechanism 6 may be electrically controlled, or may be mechanically controlled in conjunction with the incorporation of the still video mechanism 6. When the lid is removed, the focal plane shutter 10 may be automatically maintained in the open state. Furthermore, a switch for instructing the retraction (opening) of the focal plane shutter 10 may be provided on the film camera 1 side and operated by the photographer, but as described above, it is not necessary to incorporate the still video mechanism 6 into the film camera 1 side. It is desirable that this be done automatically.

In this way, by retracting the focal plane shutter 10 and quick return mirror 12 and inserting the relay lens 7 to a position close to the shadow lens 2, the position of the image pickup element 8, which is provided integrally with the relay lens 7, can also be adjusted. (2) It is closer to the shadow lens 2, and as a result, the rear protrusion of the camera can be reduced. Therefore, not only a lens shutter type camera as shown in FIG. 1, but also a film camera 1 equipped with a focal plane shutter 10,
By incorporating the still video mechanism 6, the protrusion of the rear blade of the camera can be reduced to make the camera more compact, and the movement of the eye point can also be avoided.

Note that if the focal plane shutter 10 and quick return mirror 12 are retracted when the still video mechanism 6 is installed as described above, the optical image will be constantly exposed to the image sensor 8. As shown, a mechanical shutter 17 is provided between the relay lens 7 and the image sensor 8, or the image sensor 8 is provided with an electronic shutter function.

Also, at this time, the quick return mirror 12 flips up, so the finder 3 becomes invisible. For this reason, it is desirable that the still video mechanism 6 be provided with a display device for displaying signals from the image sensor 8 on a monitor.

<Effects of the Invention> As explained above, according to the present invention, when a still video mechanism is incorporated into a film camera, the relay lens is disposed so as to protrude toward the photographing lens side from the film imaging surface. With this structure, the rear protrusion of the still video mechanism can be minimized, the camera can be made more compact, and the eye point can be prevented from moving backwards.

Furthermore, in a film camera equipped with a focal plane shutter, the focal plane shutter is kept open when the still video mechanism is installed, so the relay lens is placed closer to the photographing lens than the focal plane shutter. This allows the rear projection of the still video mechanism to be minimized as much as possible.

[Brief explanation of the drawing]

FIG. 1 is a side cross-sectional view of a film camera incorporating a still video mechanism showing a first embodiment of the present invention, FIG. 2 is a side cross-sectional view showing the configuration of a film camera according to the same embodiment, and FIG. FIG. 4 is a side sectional view of a film camera incorporating a still video mechanism showing a second embodiment of the present invention; FIG.
FIGS. 5 and 6 are side sectional views of a conventional camera. 1...Film camera 2...Photographing lens 2a.
...Imaging surface 3...Optical finder 5...Rail surface 6...Still video mechanism 7...Relay lens 8...Image sensor 10...Focal plane shutter

Claims (2)

[Claims] (1) A structure in which a still video mechanism is detachably incorporated into a film camera configured such that photographic film is attached to the imaging surface of the photographic lens, and a relay lens;
A still video mechanism including the relay lens and an image pickup element provided integrally with the relay lens is incorporated into a film camera such that the relay lens is disposed so as to protrude toward the photographic lens side from the image forming surface, A still video mechanism built-in structure in a film camera, characterized in that an optical image from the photographing lens is formed on the image pickup element via the relay lens. (2) In the structure for incorporating a still video mechanism in a film camera according to claim 1, the focal plane shutter provided in the film camera is configured to maintain an open state when the still video mechanism is incorporated. A still video mechanism built-in structure in a camera.