Photography – With exposure objective focusing means – focusing aid – or... – Mechanical mechanism for displacement of exposure objective
Reexamination Certificate
2002-05-28
2003-08-05
Perkey, W. B. (Department: 2851)
Photography
With exposure objective focusing means, focusing aid, or...
Mechanical mechanism for displacement of exposure objective
C396S151000, C396S429000, C396S535000, C396S411000, C348S064000, C348S345000, C348S374000
Reexamination Certificate
active
06603930
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a camera, which has a compact structure, and can take a photograph without losing a large format view camera function.
2. Description of the Related Art
Conventionally, photography has been carried out using a large format picture size film, e.g., a 4×5 inch format and a 5×7 inch format, or a medium format picture size film, e.g., a 6×7 cm format and a 6×9 cm format. That is, in the case of carrying out lens movement photography such that precise description is required, correction on a distortion of subject image is made and a range of focal point is widened, a large format (medium format) view camera (technical view camera)
170
as shown in FIGS.
25
(
a
),
25
(
b
) has been used. In the large format view camera
170
, a focusing screen (glass)
173
is situated on the same position as a plane (surface) of film
175
. Therefore, a user (photographer) determines a composition while directly seeing an image projected directly on the position, focuses the camera, and thereafter, takes a photograph of the image.
In the above large format view camera
170
, first, a camera main body
172
is fixed by a tripod prior to photography of a subject
171
. Thereafter, as shown in FIG.
25
(
a
), a composition setup of the subject
171
passing through a lens
174
and a focusing adjustment are carried out in the focusing screen
173
contained in a focusing screen unit
177
movably mounted to the camera main body
172
. Thereafter, as shown in FIG.
25
(
b
), a film holder
176
containing a film
175
is inserted between the camera main body
172
and the focusing screen unit
177
, and thereafter, photography is carried out. Moreover, as shown in FIG.
25
(
c
), in the case of mounting a film holder
179
containing a roll film
178
to the camera main body
172
, the focusing screen unit
177
is detached from the camera main body
172
, then, the film holder
178
is attached to the camera main body
172
, and thereafter, photography is carried out.
Thus, in the large format view camera
170
, the film holder
176
(
179
) must be attached to and detached from the camera main body
172
every one-time photography of the subject; for this reason, the attachment and detachment of the film holder is very troublesome, and a quick photographing performance is very low. Further, the image of the subject
171
projected on the focusing screen
173
becomes converse in the top and bottom of the subject; for this reason, it is difficult to adjust the composition, and as a result, the large format view camera
170
is not handy to use.
Moreover, unless the above removable type large format view camera is carefully handled, the focal point and composition thus confirmed change when the film holder
176
(
179
) is mounted to the camera main body; as a result, a photographic accuracy is reduced. In addition, after the film is loaded, it is difficult to make focusing by the focusing screen
173
, and to confirm the composition.
The large format view camera can freely control a lens back (i.e., distance between rear lens and film) On the contrary, a single-lens reflex camera has a mirror box interposed between a structural lens and a film; for this reason, the lens back (i.e., distance between rear lens and film) needs to keep a predetermined distance or more.
Thus, in the case where a focal length of an interchangeable lens is shorter than the lens back, various restrictions on lens design are made. For this reason, the lens structure becomes complicated as compared with a large format view camera lens and a range finder lens; as a result, it is difficult to produce a high-performance lens.
Further, the single-lens reflex camera is superior to the above large format view camera in a quick photographing performance and operability; however, in the case of carrying out special photography such as lens movement, the single-lens reflex camera has some restrictions.
More specifically, in the case of carrying out the above special photography such as lens movement using an ordinary single-lens reflex camera, a lens movement mechanism such as bellows is required between lens and camera main body. In the case of using the above lens movement-only adapter, an adapter is interposed between lens and camera main body; for this reason, a flange back is elongated. As a result, an ordinary interchangeable lens does not have infinite focus, and only close-up photography is possible.
Further, the single-lens reflex camera has only image circle necessary for normal photography; for this reason, a vignette (vignetting) occurs (i.e., when a too longer hood is mounted, the distal end of the hood projects on the extreme end of screen; as a result, the extreme end of screen becomes black). For this reason, a lens for only lens movement photography is required. The kind of lens movement-only lens (lens movement mechanism built-in lens) is less, and there is a restriction in its lens movement function and amount as compared with the large format view camera.
When carrying out lens movement photography using the single-lens reflex camera, there is the case where the subject is not fully confirmed on a finder.
That is, as shown in FIG.
26
(
a
), there is the case where a part of light passing (transmitting) through a lens
181
and incident on a film plane
184
is not reflected on a mirror
182
depending upon lens movement position and amount of the movement. For this reason, no entire image of the subject exposed on the film plane
184
appears in a focusing screen
183
. As a result, a shadow is generated in the upper side of the screen on the finder although the image is projected on the film plane, and thereby, a phenomenon (short of mirror length) M incapable of confirming the entire subject is generated.
Further, as shown in FIG.
26
(
b
), there is the case where the following phenomenon is generated; more specifically, the light passing through the lens
181
is incident directly upon the focusing screen
183
from the lens
181
without being reflected by the reflecting mirror
182
, and then, is imaged.
For this reason, in the photography incapable of allowing a failure, in the case of a film holder interchangeable camera, in order to previously confirm the subject projected on the film plane, the film holder is interchanged with a Polaroid film holder or a digital camera back, and thereafter, test photography is carried out. Further, in a state that the focusing screen is attached to the film plane, the subject is confirmed as the large format view camera.
SUMMARY OF THE INVENTION
The present invention has been made in order to solve the above problems. Therefore, an object of the present invention is to provide a camera having the following structure. In the camera, a main body is provided with a rotating member, which is rotated along a guide of the main body, and the rotating member is connected with an operating means for rotating the rotating member. A focusing screen is mounted to the rotating member so as to correspond to a luminous flux section of a lens unit. A reflecting member for reflecting a subject image captured from the lens unit to a finder provided in the main body is mounted at a backside of the focusing screen in the rotating member. A case member containing an image pickup member corresponding to the luminous flux section of the lens unit is provided at the other side of the focusing screen via the reflecting member in the rotating member.
According to the above construction of the present invention, it is possible to provide a camera, which has a compact-sized structure, and can perform the same photography effect as a large format view camera and high operability even if it is a small size.
REFERENCES:
patent: 1900730 (1933-03-01), Petit et al.
patent: 5570146 (1996-10-01), Collette
patent: 6404991 (2002-06-01), Gfeller
Kanesaka & Takeuchi
Perkey W. B.
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