Digital Camera Patent AbstractA digital camera includes a photographic lens that is provided on
a camera body of the digital camera so that an optical axis of the
photographic lens is stationary with respect to the camera body;
an image pick-up element on which an image of an object to be photographed,
which is formed through the photographic lens, is impinged; and
a tilting/swinging mechanism, provided in the camera body, for tilting
and/or swinging the image pick-up element relative to a plane orthogonal
to the optical axis.
Digital Camera Patent ClaimsWhat is claimed is:
1. A digital camera comprising: a photographic lens provided on
a camera body of the digital camera, the photographic lens defining
an optical axis that is stationary with respect to the camera body;
an image pick-up element on which an image formed by the photographic
lens images, the image pick-up element comprising a sensitive surface
that intersects the optical axis at an intersection point; a tilting/swinging
mechanism, provided in the camera body, that enables concurrent
compound movement of the image pick-up element, relative to the
optical axis, in at least two orthogonal planes such that the sensitive
surface rotates about the intersection point, said tilting/swinging
mechanism being configured to enable the concurrent compound movement
of the image pick-up device by a single operation member.
2. The digital camera according to claim 1, the tilting/swinging
mechanism comprising: a mount to which the image pick-up element
is fixed, the mount comprising a convex surface; and a base, fixed
to the camera body, comprising a concave surface having a radius
of curvature corresponding to a radius of curvature of the convex
surface; wherein the mount is mounted on the base such that the
convex surface is slidable on the concave surface.
3. The digital camera according to claim 2, the tilting/swinging
mechanism further comprising an operation member fixed to the mount,
enabling movement of the mount relative to the base.
4. The digital camera according to claim 1, the tilting/swinging
mechanism comprising: a mount to which the image pick-up element
is fixed, the mount comprising a convex spherical surface which
defines a portion of a sphere having a center point coincident with
the intersection point between the optical axis and the sensitive
surface of the image pick-up element; and a base, fixed to the camera
body, comprising a concave spherical surface having a radius of
curvature corresponding to a radius of curvature of the convex surface,
the mount being mounted on the base such that the convex spherical
surface is slidable on the concave spherical surface; wherein a
sliding movement of the convex spherical surface on the concave
spherical surface causes the sensitive surface of the image pick-up
element to rotate about the intersection point.
5. The digital camera according to claim 4, further comprising
an operation member, fixed to the mount, that enables movement of
the mount relative to the base.
6. The digital camera according to claim 1, wherein the intersection
point is stationary with respect to the camera body.
7. The digital camera according to claim 1, wherein the concurrent
compound movement of the image pick-up element enabled by the tilting/swinging
mechanism comprises spherical movement.
8. The digital camera according to claim 1, wherein the concurrent
compound movement of the image pick-up element enabled by the tilting/swinging
mechanism comprises skewing movement relative to two orthogonal
planes.
9. The digital camera according to claim 1, said tilting/swinging
mechanism comprising a convex spherical surface and a concave spherical
surface mounted for relative slidable motion therebetween.
10. A digital camera having a photographic lens and an image pick-up
element, the photographic lens being attached to a camera body of
the digital camera such that an optical axis of the photographic
lens is stationary with respect to the camera body, an image of
an object to be photographed impinging on the image pick-up element
through the photographic lens, the digital camera comprising: a
tilting/swinging mechanism, provided in the camera body, configured
to at least one of tilt and swing a sensitive surface of the image
pick-up element by concurrent compound movement, in at least two
orthogonal planes, relative to the optical axis, wherein the tilting/swinging
mechanism comprises: a movable member to which the image pick-up
element is fixed; and a stationary member to which the movable member
is rotatably connected to enable the movable member to move relative
to the stationary member to enable at least one of tilting and swinging
the sensitive surface relative to a point at which the sensitive
surface intersects the optical axis, said tilting/swinging mechanism
being configured to enable the concurrent compound movement of the
image pick-up device by a single operation member.
11. The digital camera according to claim 10, wherein the point
at which the sensitive surface intersects the optical axis remains
stationary with respect to the camera body.
12. The digital camera according to claim 10, wherein the concurrent
compound movement of the image pick-up element enabled by the tilting/swinging
mechanism comprises spherical movement.
13. The digital camera according to claim 10, wherein the concurrent
compound movement of the image pick-up element enabled by the tilting/swinging
mechanism comprises skewing movement relative to two orthogonal
planes.
14. The digital camera according to claim 10, said tilting/swinging
mechanism comprising a convex spherical surface and a concave spherical
surface mounted for relative slidable motion therebetween.
15. A digital camera comprising: a photographing lens attached
to a camera body, the photographing lens defining an optical axis
that is stationary with respect to the camera body; an image pick-up
element comprising a sensitive surface that intersects the optical
axis at an intersection point; a rotatable mount having the image
pick-up element attached to one side and defining a convex spherical
surface on an opposite side, a radius of the convex spherical surface
being centered on the intersection point; and a base, fixed to the
camera body, defining a concave spherical surface that slidably
cooperates with the convex spherical surface of the rotatable mount;
wherein movement of the rotatable mount with respect to the base
rotates the sensitive surface around the intersection point.
16. The digital camera according to claim 15, wherein the intersection
point is stationary with respect to the camera body. Digital Camera Patent DescriptionBACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a digital camera provided with
a tilting/swinging mechanism.
2. Description of the Related Art
In conventional tilting/swinging photography with a camera using
sensitive film, the photographic lens is moved (tilted or swung)
relative to the camera body in which the sensitive film is fixedly
positioned. More specifically, conventional tilting/swinging photography
with a camera using sensitive film is known for being able to sharply
focus entirely on a surface of an object which is inclined to a
plane orthogonal to the optical axis of the photographic lens by
tilting or swinging the optical axis of the photographic lens relative
to the direction normal to the film plane. In theory, the camera
can be sharply focused entirely on a surface of an object which
is inclined to a plane orthogonal to the optical axis of the photographic
lens by making the extended surface of the film surface, the extended
surface of the object surface, and the extended surface of a lens
surface intersect one another along a straight line, according to
the Scheimpflug principle.
In such conventional tilting/swinging photography, it is necessary
to use a complicated mechanism for tilting or swinging the lens
mount plate to which the photographic lens is fixed relative to
the camera body, which inevitably increases the size of the camera
body. In the case of performing the tilting/swinging photography
with a digital camera, if the tilting/swinging mechanism designed
for a camera using sensitive film is applied to the digital camera,
the image plane tends to move largely relative to the sensitive
surface of the image pick-up device (e.g., a CCD) of the digital
camera, because the image pick-up device is generally smaller than
a film surface (the sensitive surface of a film frame).
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a digital camera
having a simple tilting/swinging mechanism which does not increase
the size of the camera body, and makes it possible to perform tilting/swinging
photography with little movement of the image plane relative to
the sensitive surface of the image pick-up device of the digital
camera.
To achieve the object mentioned above, according to the present
invention, a digital camera is provided, including a photographic
lens that is provided on a camera body of the digital camera so
that an optical axis of the photographic lens is stationary with
respect to the camera body; an image pick-up element on which an
image of an object formed by the photographic lens, is impinged;
and a tilting/swinging mechanism, provided in the camera body, wherein
the tilting/swinging mechanism can cause a tilting or (and) swinging
movement of the image pick-up element relative to a plane orthogonal
to the optical axis.
Preferably, the tilting/swinging mechanism is designed so that
the image pick-up element can be operated to rotate about a point
of intersection between the optical axis and a sensitive surface
of the image pick-up element.
In an embodiment, the tilting/swinging mechanism includes a mount
to which the image pick-up element is fixed, the mount having a
convex surface; and a base fixed to the camera body, the base having
a concave surface having a radius of curvature corresponding to
a radius of curvature of the convex surface. The mount is mounted
on the base with the convex surface being slidable on the concave
surface. Preferably, the tilting/swinging mechanism further includes
an operation member which is fixed to the mount so that the mount
can be moved relative to the base by operating the operation member.
In an embodiment, the tilting/swinging mechanism includes amount
to which the image pick-up element is fixed, the mount having a
convex spherical surface having a center coincident with a point
of intersection between the optical axis and a sensitive surface
of the image pick-up element; and a base fixed to the camera body,
the base having a concave spherical surface having a radius of curvature
corresponding to a radius of curvature of the convex spherical surface.
A sliding movement of the convex spherical surface on the concave
spherical surface causes the image pick-up element to rotate about
the point of intersection. Preferably, an operation member is provided,
which is fixed to the mount so that the mount can be moved relative
to the base by operating the operation member.
According to another aspect of the present invention, a digital
camera is provided, having a photographic lens and an image pick-up
element, the photographic lens being provided on a camera body of
the digital camera so that an optical axis of the photographic lens
is stationary with respect to the camera body, an image of an object
to be photographed being impinged on the image pick-up element through
the photographic lens, the digital camera includes a tilting/swinging
mechanism, provided in the camera body, wherein the tilting/swinging
mechanism can cause a tilting or (and) swinging movement of a sensitive
surface of the image pick-up element relative to a plane orthogonal
to the optical axis. The tilting/swinging mechanism includes a movable
member to which the image pick-up element is fixed, and a stationary
member to which the movable member is connected so that the movable
member can move relative to the stationary member so as to tilt
or swing the image pick-up element relative to the plane.
The present disclosure relates to subject matter contained in Japanese
Patent Application No. 11-266542 (filed on Sep. 21, 1999) which
is expressly incorporated herein by reference in its entirety.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be discussed below in detail with reference
to the accompanying drawings, in which:
FIG. 1 is a perspective view of fundamental elements, which support
an image pick-up device, of an embodiment of a tilting/swinging
mechanism according to the present invention;
FIG. 2 is a schematic sectional view of a digital camera having
the tilting/swinging mechanism shown in FIG. 1, taken along the
line II--II in FIG. 1; and
FIG. 3 is a block diagram of an image pick-up system of the digital
camera shown in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of a digital camera according to the present invention
is provided with an image pick-up system shown in FIG. 3. As shown
in FIG. 3, this system includes an image pick-up element (e.g.,
a CCD) 11, a photographic lens 18, an LCD viewfinder 21, a recording
medium (e.g., an internal memory) 22, an operation switch 23 and
a system control circuit 24. An object image is focused on the sensitive
surface of the image pick-up element 11 through the photographic
lens 18. The image pick-up element 11 converts the object image
focused on the sensitive surface thereof into a picture signal.
In accordance with an operation of the operation switch 23, the
system control circuit 24 selects either a finder mode, in which
the picture signal is viewed through the LCD viewfinder 21, or a
photographing mode, in which the picture signal is recorded in the
recording medium 22.
FIG. 2 is a schematic sectional view of a digital camera of the
present embodiment according to the present invention. The digital
camera is not provided with a mechanism for tilting or swinging
the photographic lens 18 relative to the camera body 10. The photographic
lens 18 is supported by the camera body 10 so that the optical axis
20 of the photographic lens 18 is stationary with respect to the
camera body 10.
The image pick-up element 11, which is positioned behind the photographic
lens 18 (below the photographic lens 18 as viewed in FIG. 2), is
fixed to a front face (top face as viewed in FIG. 2) of a mount
(movable member) 12 at a position where an image formed through
the photographic lens 18 is focused on the sensitive surface 19
of the image pick-up element 11. The image obtained through the
image pick-up element 11 can be seen through the LCD viewfinder
21.
The mount 12 is provided on the rear face thereof with a convex
spherical surface 13 having a center coincident with the intersection
between the optical axis 20 and the sensitive surface 19 of the
image pick-up element 11. The convex spherical surface 13 has a
radius of curvature "R" as shown in FIG. 2. The mount
12 is mounted on a base (stationary member) 14 fixed to the camera
body 10. The base 14 is provided on the front face thereof with
a concave spherical surface 15 whose radius of curvature is identical
to that of the convex spherical surface 13. Accordingly, the mount
12 is mounted on the base 14 with the convex spherical surface 13
being slidable on the concave spherical surface 15.
FIG. 1 is a perspective view of the image pick-up element 11, the
mount 12 and the base 14 on which the mount 12 is mounted to be
slidable thereon, showing the positional relationship amount the
image pick-up element 11, the mount 12 and the base 14. The mount
12 is slidably mounted on the base 14 so as not to come off the
base 14 by attracting the mount 12 on the base 14 by, for example,
magnetic or spring force. The rear face of the base 14 is secured
to the camera body 10. As can be seen in FIG. 2, a through hole
16 is formed between the base 14 and the camera body 10 to extend
rearward from the concave spherical surface 15 to the outside of
the camera body 10. The mount 12 is provided with an operation stick
(operation member) 17 which extends rearward from substantially
the center of the convex spherical surface 13 to project to the
outside of the camera body 10 via the through hole 16. The mount
12 can be moved (tilted and/or swung) relative to the camera body
10 by operating the operation stick 17 from the outside of the camera
body 10. The mount 12, the base 14 and the operation stick 17 constitute
a tilting/swinging mechanism.
Upon a photographic operation, first of all the user views the
object through the LCD viewfinder 21. When it is necessary to carry
out the tilting/swinging operation so as to adjust perspective and
depth of field, the user operates the operation stick 17 to tilt
the sensitive surface 19 of the image pick up element 11 relative
to the optical axis 20 horizontally and/or vertically while viewing
the object through the LCD viewfinder 21. During this tilting/swinging
operation, the sensitive surface 19 of the image pick-up element
11 rotates about the center of the sensitive surface 19, namely,
tilts relative to a plane orthogonal to the optical axis 20 without
varying the position of the center of the sensitive surface 19 relative
to the camera body 10. Therefore, the image pick-up element 11 can
be tilted relative to the optical axis 20 horizontally and vertically
without varying the position of the point of intersection between
the optical axis 20 and the sensitive surface 19 of the image pick-up
element 11. After this tilting/swinging operation is completed,
a picture is taken in a photographing mode, which is selected via
the operation switch 23.
In the illustrated embodiment, although the mount 12 is provided
with a spherical surface (the convex spherical surface 13) while
the base 14 is provided with a corresponding spherical surface (the
concave spherical surface 15) so that the image pick-up element
11 can tilt to various angles without varying the position of the
center of the sensitive surface 19 relative to the camera body 10,
the present invention is not limited solely to this particular embodiment.
For instance, the mount 12 can be provided with a cylindrical surface
(e.g., a convex cylindrical surface) while the base 14 can provided
with a corresponding cylindrical surface (e.g., a concave cylindrical
surface) so that the image pick-up element 11 can tilt either only
horizontally (i.e., swing) or only vertically (i.e., tilt) without
varying the position of the center of the sensitive surface 19 relative
to the camera body 10.
As can be understood from the foregoing, according to a digital
camera having a tilting/swinging mechanism to which the present
invention is applied, a tilting/swinging mechanism having a simple
structure can be obtained.
Obvious changes may be made in the specific embodiment of the present
invention described herein, such modifications being within the
spirit and scope of the invention claimed. It is indicated that
all matter contained herein is illustrative and does not limit the
scope of the present invention.
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