Digital Camera Patent Abstract
A digital camera which includes: a photographic lens movable along
an optical axis thereof between a retracted position and a photographing
position in front of the retracted position; an image pick-up device
on which an object image is formed through the photographic lens,
the image pick-up device being guided to be movable between a first
position where the image pick-up device is positioned in a photographic
optical path of the photographic lens behind the photographic lens
and a second position where the image pick-up device is positioned
out of the photographic optical path; and a mechanism for moving
the image pick-up device between the first position and the second
position, wherein the moving mechanism moves the image pick-up device
to the first position when the photographic lens is moved from the
retracted position to the photographing position, and wherein the
moving mechanism moves the image pick-up device to the second position
when the photographic lens is moved from the photographing position
to the retracted position. Digital Camera Patent Claims
What is claimed is:
1. A digital camera comprising:
a photographic lens movable along an optical axis thereof between
a retracted position and a photographing position in front of said
retracted position;
image pick-up device on which an object image is formed through
said photographic lens, said image pick-up device being guided to
be movable between a first position where said image pick-up device
is positioned in a photographic optical path of said photographic
lens behind said photographic lens and a second position where said
image pick-up device is positioned out of said photographic optical
path; and
a mechanism for moving said image pick-up device between said first
position and said second position, wherein said moving mechanism
moves said image pick-up device to said first position when said
photographic lens is moved from said retracted position to said
photographing position, and wherein said moving mechanism moves
said image pick-up device to said second position when said photographic
lens is moved from said photographing position to said retracted
position.
2. The digital camera according to claim 1, wherein said image
pick-up device is guided in a direction perpendicular to said optical
axis.
3. The digital camera according to claim 1, wherein said moving
mechanism moves said image pick-up device from said first position
to said second position before said photographic lens reaches said
retracted position.
4. The digital camera according to claim 3, wherein a rear end
of said photographic lens moves into a space previously occupied
by said image pick-up device when said photographic lens moves from
said photographing position to L1 said retracted position.
5. The digital camera according to claim 1, wherein said moving
mechanism comprises a support plate to which the image pick-up device
is secured, said support plate being pivoted about a shaft secured
to a body of said digital camera so that said image pick-up device
is movable between said first position and said second position.
6. The digital camera according to claim 5, wherein said shaft
extends parallel to said optical axis.
7. The digital camera according to claim 1, wherein said photographic
lens comprises:
a lens barrel movable along said optical axis between said retracted
position and said photographing position; and
a photographic optical system comprising a front lens group and
a rear lens group, at least said rear lens group being supported
by said movable lens barrel;
wherein said moving mechanism further comprises an interlocking
mechanism, provided between said image pick-up device and said movable
lens barrel, for moving said image pick-up device between said first
position and said second position in association with the movement
of said movable lens barrel between said photographing position
and said retracted position.
8. The digital camera according to claim 5, wherein said moving
mechanism further comprises a spring for continuously urging said
support plate in a direction to move said image pick-up device to
said first position.
9. The digital camera according to claim 5, wherein said photographic
lens is a motor-driven zoom lens, said moving mechanism further
comprises:
a cam plate guided in a direction perpendicular to the optical
axis, said cam plate being moved in association with the movement
of said photographic lens; and
an interlocking mechanism, provided between said image pick-up
device and said cam plate, for moving said image pick-up device
between said first position and said second position in association
with the movement of said cam plate.
10. The digital camera according to claim 9, further comprising:
a zoom finder which varies a magnification thereof in association
of the variation of a focal length of said photographic lens, said
zoom finder comprising at least one movable lens group having a
follower,
wherein said cam plate comprises a cam slot in which said follower
is fitted.
11. The digital camera according to claim 10, further comprising:
a strobe which varies an angle of illumination thereof in association
of said variation of said focal length of said photographic lens,
said strobe comprising a movable light emitting unit having a second
follower,
wherein said cam plate comprises a second cam slot in which said
second follower is fitted.
12. The digital camera according to claim 7, wherein said moving
mechanism further comprises a support plate to which the image pick-up
device is secured, said support plate being pivoted about a shaft
secured to a body of said digital camera so that said image pick-up
device is movable between said first position and said second position,
wherein said interlocking mechanism comprises:
a link bar pivoted about a shaft secured to said camera body, one
end of said link bar having a follower, the other end of said link
bar engaging with said support plate; and
a cam groove formed on said movable lens barrel, said follower
being fitted in said cam groove.
13. A digital camera having a retractable photographic lens, comprising:
an image pick-up device on which an object image is focused through
said photographic lens; and
a mechanism for positioning said image pick-up device in a photographic
optical path of said photographic lens behind said photographic
lens when a power switch of said digital camera is turned ON, and
for positioning said image pick-up device out of said photographic
optical path when said power switch is turned OFF.
Digital Camera Patent Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a digital camera provided with
an image pick-up device such as a CCD for converting an image of
an object into electric signals.
2. Description of the Related Art
A digital camera (digital imaging camera) generally includes an
image pick-up device such as a CCD (charge-coupled device) for converting
an object image formed thereon through the photographic lens of
the camera into electric signals which are then converted into digital
signals. The digital signals are generally stored in a recording
medium such as a flash memory or a memory card in a predetermined
format.
In a conventional digital camera, it is difficult to reduce the
thickness of the camera body because a bulky image pick-up device
is positioned in the camera body behind the photographic lens. Even
if the camera is designed to have a retractable photographic lens
for the purpose of reducing the thickness of the camera body when
the camera is not in use, it is still difficult to reduce the thickness
because a sufficient space in which the photographic lens is to
retract cannot be secured in front of the bulky image pick-up device
within a thin camera body.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a digital camera
having structure which makes it possible to design the camera body
to be thin in the direction of the optical axis of the photographic
lens of the camera.
To achieve the object mentioned above, according to an aspect of
the present invention, there is provided a digital camera which
includes: a photographic lens movable along an optical axis thereof
between a retracted position and a photographing position in front
of the retracted position; an image pick-up device on which an object
image is formed through the photographic lens, the image pick-up
device being guided to be movable between a first position where
the image pick-up device is positioned in a photographic optical
path of the photographic lens behind the photographic lens and a
second position where the image pick-up device is positioned out
of the photographic optical path; and a mechanism for moving the
image pick-up device between the first position and the second position,
wherein the moving mechanism moves the image pick-up device to the
first position when the photographic lens is moved from the retracted
position to the photographing position, and wherein the moving mechanism
moves the image pick-up device to the second position when the photographic
lens is moved from the photographing position to the retracted position.
Preferably, the image pick-up device is guided in a direction perpendicular
to the optical axis.
Preferably, the moving mechanism moves the image pick-up device
from the first position to the second position before the photographic
lens reaches the retracted position.
According to another aspect of the present invention, there is
provided a digital camera having a retractable photographic lens.
The digital camera includes: an image pick-up device on which an
object image is focused through the photographic lens; and a mechanism
for positioning the image pick-up device in a photographic optical
path of the photographic lens behind the photographic lens when
a power switch of the digital camera is turned ON, and for positioning
the image pick-up device out of the photographic optical path when
the power switch is turned OFF.
The present disclosure relates to subject matter contained in Japanese
Patent Application No. 09-155144 (filed on Jun. 12, 1997) which
is expressly incorporated herein by reference in its entirety.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be described below in detail with reference
to the accompanying drawings in which:
FIGS. 1A, 1B and 1C are schematic sectional views of a photographic
optical system and an image pick-up unit in different positions,
showing a fundamental structure of a digital camera to which the
present invention is applied;
FIG. 2 is a perspective view of fundamental cements of a first
embodiment of the digital camera to which the present invention
is applied;
FIG. 3 is a plan view of a cam groove formed on a cam ring shown
in FIG. 2;
FIG. 4 is a perspective view of fundamental elements of a second
embodiment of the digital camera to which the present invention
is applied; and
FIG. 5 is a plan view of a cam slot formed on a cam plate shown
in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1A, 1B and 1C show a fundamental structure of a digital camera
to which the present invention is applied. The camera is provided
with a zoom lens 11 consisting of two lens groups, i.e., a front
lens group L1 and a rear lens group L2. The front and rear lens
groups L1 and L2 are moved along an optical axis O of the zoom lens
11 while varying the distance therebetween to effect zooming and
focusing.
The camera is provided with an image pick-up unit (image pick-up
device) 21. The image pick-up unit 21 is provided with a base plate
25 to which a CCD 24 is fixed. A set of filters 23 including a low-pass
filter and an infrared filter are secured to the CCD 24 between
the rear lens group L2 and the CCD 24. The base plate 25 is guided
in a direction perpendicular to the optical axis O to be selectively
movable between a first position where the CCD 24 is positioned
behind the rear lens group L2 (see FIG. 1A or 1B) and a second position
where the CCD 24 is positioned out of the photographic optical path
of the zoom lens 11 (see FIG. 1C). The base plate 25 is moved between
the first and second positions by a drive mechanism (not shown in
any of FIGS. 1A, 1B and 1C). In each of FIGS. 1A, 1B and 1C reference
numeral 13 designates an inner surface of a wall (e.g., a back wall)
of a camera body of the camera.
FIG. 1A shows the zoom lens 11 and the image pick-up unit 21 in
a photo-ready condition with the power switch of the camera turned
ON. FIG. 1B shows the zoom lens 11 and the image pick-up unit 21
in a non-photographable condition with the zoom lens 11 retracted
and with the image pick-up unit 21 still positioned behind the rear
lens group L2. FIG. 1C shows the-zoom lens 11 and the image pick-up
unit 21 in a non-photographable condition with the zoom lens 11
retracted and with the image pick-up unit 21 positioned out of the
photographic optical path of the zoom lens 11. In the photo-ready
condition shown in FIG. 1A, the front and rear lens groups L1 and
L2 are each advanced forwardly with the rear lens group L2 being
sufficiently apart from the image pick-up unit 21, and the front
and rear lens groups L1 and L2 are adjusted by a focusing device
(not shown) to form a sharp object image on the light receiving
surface of the CCD 24. The camera is provided therein with an image
processing circuit (not shown). The electric image signals output
from the CCD 24 are transmitted to the image processing circuit
via a cable (not shown) to be converted by the image processing
circuit into digital data in a predetermined format. The digital
data is stored in a recording medium such as a flash memory or a
memory card, or is output from the camera.
When the power switch is turned off, the front and rear lens groups
L1 and L2 are retracted to respective rearmost positions (retracted
positions) and at the same time the image pick-up device 21 is moved
out of the photographic optical path of the zoom lens 11, as shown
in FIG. 1C. In the case where the zoom lens 11 is retracted with
the image pick-up device 21 still positioned behind the rear lens
group L2 in the photographic optical path of the zoom lens 11, the
rear lens group L2 cannot be moved back beyond the position of the
front end of the image pick-up device 21, namely, the rear lens
group L2 cannot retreat to a position where it contacts the filter
set 23. FIG. 1B shows a state where the front and rear lens groups
L1 and L2 are retracted with the image pick-up device 21 remained
to be positioned behind the rear lens group L2. In the state shown
in FIG. 1B, "A" designates a distance between the front
end of the front lens group L1 and the back surface of the base
plate 25. In FIG. 1B "C" designates the thickness of the
image pick-up unit 21. The thickness C is approximately 7 to 8 mm.
In the digital camera to which the present invention is applied,
the image pick-up unit 21, which includes the CCD 24, is moved out
of the photographic optical path of the zoom lens 11 in the direction
perpendicular to the optical axis O when the zoom lens 11 is retracted,
which makes it possible to further retract the zoom lens 11 in the
camera body. Therefore, it is possible to retract the zoom lens
11 to a position where the rear end of the rear lens group L2 almost
contacts the inner surface 13 of the camera body. That is, if the
image pick-up unit 21 is moved off the photographic optical path,
the zoom lens 11 can further retreat by a length corresponding to
thickness C of the image pick-up unit 21. It is therefore possible
to thin the camera body by thickness C (see FIG. 1C). It is otherwise
possible to lengthen a lens barrel for supporting the zoom lens
11 by thickness C, which makes it possible to provide the camera
body with a zoom lens having a longer focal length or a higher zoom
ratio.
The image pick-up unit 21 may be moved into and out of the photographic
optical path by any drive mechanism.
The zoom lens 11 and the image pick-up unit 21 may be moved by
a common motive power source or by different motive power sources.
FIG. 2 shows fundamental elements of a first embodiment of the
digital camera to which the present invention is applied. This first
embodiment is characterized in that the image pick-up unit 21 is
inserted into and taken out of the photographic optical path by
the linear movement of a movable lens barrel 31. The image pick-up
unit 21 is in the photographic optical path behind the zoom lens
11 as shown by solid lines in FIG. 2 when the lens barrel 31 is
positioned in an advanced position (photographing position). The
image pick-up unit 21 is moved out of the photographic optical path
behind the zoom lens 11 as shown by two-dot chain lines in FIG.
2 when the lens barrel 31 retreats into the camera body.
The image pick-up unit 21 is secured to a support plate 41 having
a leg portion 42. The leg portion 42 is pivoted about a shaft 43
which extends in parallel to the optical axis O. The shaft 43 is
fixed to the camera body (not shown in FIG. 2).
A tension spring 46 extends between the support plate 41 and a
pin 45 which is fixed to the camera body. The spring 46 urges the
plate 41 in one direction around the shaft 43 (clockwise direction
as viewed in FIG. 2). The urged plate 41 is stopped by a locating
pin 47 fixed to the camera body to position the image pick-up unit
21 in the photographing position. When the image pick-up unit 21
is in this position, an object image is formed on the light receiving
surface of the image pick-up unit 21 through the zoom lens 11. The
image pick-up unit 21 is moved out of the photographic optical path
including the optical axis O when the support plate 41 is rotated
about the shaft 43 counterclockwise as viewed in FIG. 2 against
the spring force of the spring 46.
A link bar 51 is positioned nearby the lens barrel 31. A central
portion of the link bar 51 is pivoted about a shaft 52 extending
perpendicularly to the optical axis O. The shaft 52 is secured to
the camera body. The link bar 51 is provided at the front end thereof
with a follower pin 53. The lens barrel 31 is provided with a cam
groove 33 in which the follower pin 53 is fitted. The other end
48 of the link bar 51 is bent to have an engaging portion 54 which
is engaged with an upper edge of the leg portion 42 of the support
plate 41. When the link bar 51 rotates clockwise as viewed in FIG.
2, the support plate 41 is rotated counterclockwise about the shaft
43 by the rotational movement of the link bar 51 to be positioned
in a retracted position (shown by two-dot chain line in FIG. 2)
against the spring force of the spring 46.
FIG. 3 shows the contour of the cam groove 33 The cam groove 33
includes a zooming section between T and W which extends in parallel
with the optical axis O. The lens barrel 31 is moved linearly, without
rotating about the optical axis O. When the lens barrel 31 is moved
linearly to effect zooming, the follower pin 53 is fitted in the
cam groove 33 within the zooming section between T and W. This maintains
the link bar 51 in the position (shown by solid lines in FIG. 2)
where the bar 51 does not turn the support plate 41 from its photographing
position to retracted position. The cam groove 33 also includes
a retracting section between W and S which extends inclined to the
optical axis O and the zooming section between T and W. When the
lens barrel 31 is retracted upon the power switch being turned OFF,
the cam pin 53 moves from the zooming section between T and W to
the end 33a of the retracting section between W and S, which turns
the link bar 51 to the retracted position shown by two-dot chain
lines in FIG. 2.
FIG. 4 shows fundamental elements of a second embodiment of the
digital camera to which the present invention is applied. The digital
camera is provided with a motor-driven zoom lens, the basic structure
of which is disclosed in, e.g., Japanese Laid-Open Patent Publication
62-285632. The camera is provided with a zoom lens barrel block
101, a finder and strobe block 112, a distance measuring device,
and a zoom motor 116. The distance measuring device includes a set
of light emitter and receiver 113. Those components 101, 112, 113
and 116 are supported by or mounted on the camera body.
The barrel block 101 is provided with a cam ring 102, a front barrel
103 and a rear barrel 104. Each of the barrels 103 and 104 is fitted
in the cam ring 102 and is moved forwardly and rearwardly by the
rotation of the cam ring 102. The barrels 103 and 104 support front
and rear lens groups L1 and L2 (not shown in FIG. 4) thereinside,
respectively. Each barrel can be moved between a retracted position
and a photographing position. Each barrel is moved within a zooming
range including the photographing position as the cam ring 102 rotates.
The finder and strobe block 112 is provided with a zoom finder
118 and a strobe 119. In accordance with the variation in the focal
length of the zoom lens 11, the finder 118 changes its magnification
and field of view while the strobe 119 changes its angle of illumination.
The cam ring 102 is provided on an outer periphery thereof with
a sector gear 105 which extends along the circumference of the cam
ring 102. The sector gear 105 meshes with a drive pinion 107 which
is fixed to the drive shaft of the zoom motor 116. The sector gear
105 also meshes with a driven pinion 120 which is fixed to the front
end of a shaft 121 which extends in parallel to the optical axis
O. The shaft 121 is provided at the rear end thereof with a first
gear 122a. This first gear 122a meshes with a second gear 122b which
meshes with a rack 123a formed on a cam plate 123. The first and
second gears 122a and 122b constitute a reduction gear train 122
for transmitting rotation of the cam ring 102 to the rack 123a while
lowering the output speed. Accordingly, the rotation of the cam
ring 102 is transmitted to the cam plate 123 through the sector
gear 105, the driven pinion 120, the shaft 121, the reduction gear
train 122 and the rack 123a. The rotational position (angular position)
of the ring 102 is detected through a code plate 130 secured to
the outer periphery of the ring 102 and conductive brushes 131 slidably
contacting the code plate 130.
The cam plate 123 is guided horizontally in a direction perpendicular
to the optical axis O of the zoom lens. The cam plate 123 is provided
along a rear end thereof with a downwardly extending bent portion
123b. The aforementioned rack 123a, which meshes with the second
gear 122b, is formed on the bottom end of the bent portion 123b
therealong. The cam plate 123 is provided with a first cam slot
125 for varying the magnification of the finder 118 and a second
cam slot 127 for varying the angle of illumination of the strobe
119.
The finder optical system of the finder 118 consists of three lens
groups, i.e., a fixed object lens group L3, a fixed eyepiece lens
group L4 and a movable lens group L5 positioned between the object
lens group L3 and the eyepiece lens group L4. The magnification
of the finder 118 varies by moving the movable lens group L5 along
the optical axis of the finder 118. The movable lens group L5 is
provided with a follower pin 118a which is fitted in the first cam
slot 125. The movable lens group L5 is moved to vary the magnification
of the finder 118 such that the field of view of the finder 118
is coincident with the size of a picture which is varied due to
the variation of the focal length of the zoom lens in the barrel
block 101.
As the focal length of the zoom lens becomes longer, the strobe
119 narrows the angle of illumination. For a close shot, the strobe
119 widens the angle of illumination, reducing the illuminance level
on an object which is to be photographed. For this, the strobe 119
is provided with a fixed Fresnel lens L6 and a reflector 129 which
holds a xenon lamp (not shown). The reflector 129 is provided with
a follower pin 119a which is fitted in the second cam slot 127 so
as to be driven to move along its optical axis by the movement of
the cam plate 123.
The turning of the cam ring 102 causes the cam plate 123 to move
right and left. When the zoom lens 11 is retracted, i.e., when the
front and rear barrels 103 and 104 are retracted, the cam plate
123 is positioned in its position closest to the barrel block 101.
When the zoom lens 11 is positioned within the photographing range,
that is, within the zooming range, the cam plate 123 is away from
the barrel block 101. This second embodiment is characterized in
that the image pick-up unit 21 is moved between the photographing
position and the retracted position by the movement of the cam plate
123.
The contour of each of the first and second cam slots 125 and 127
is determined in association with the rotational position (angular
position) of the cam ring 102. Namely, the contour of each cam slot
is determined such that points T, W and S of each cam slot correspond
to a telephoto-extremity angular position A, a wide-angle-extremity
angular position B and a retracted angular position C of the cam
ring 102, respectively. The section of each cam slot between the
points T and W is determined to correspond to the angle of rotation
of the cam ring 102 between the angular positions A and B. Likewise,
the section of each cam slot between the points W and S is determined
to correspond to the angle of rotation of the cam ring 102 between
the angular positions B and C. The sections between the points T
and W of the first and second cam slots 125 and 127 are each inclined
relative to the direction of movement of the cam plate 123 so as
to vary the magnification of the finder 118 and the angle of illumination
of the strobe 119, respectively, in accordance with the variation
of the focal length of the zoom lens 11. The retracting sections
between the points W and S of the first and second cam slots 125
and 127 are each parallel with the direction of movement of the
cam plate 123, so that neither the magnification of the finder 118
nor the angle of illumination of the strobe 119 varies as long as
the follower pins 118a and 119a move within the sections between
W and S of the cam slots 125 and 127, respectively. Rotation of
the cam ring 102 between its angular positions B and C, which respectively
correspond to the points W and S, causes the image pick-up unit
21 to move between the photographing position (shown by solid lines
in FIG. 4) and the retracted position (shown by two-dot chain lines
in FIG. 4).
The image pick-up unit 21 is secured to a support plate 61 which
lies in a plane perpendicular to the optical axis O of the zoom
lens 11. The support plate 61 is provided with an L-shaped leg portion
62. An end of the leg portion 62 is bent rearwards and further bent
upwards to form a crank portion 62a having an L-shape cross section.
The crank portion 62a is pivoted about a shaft 63 which extends
in parallel with the optical axis O. The shaft 63 is fixed to the
camera body (not shown).
A tension spring 66 extends between the support plate 61 and a
pin 65 which is fixed to the camera body. The support plate 61 is
urged in one direction by the spring 66 and stopped by a locating
pin 67 fixed to the camera body to position the image pick-up unit
21 in the photographing position. When the image pick-up unit 21
is in the photographing position, an object image is formed on the
light receiving surface of the image pick-unit 21 through the zoom
lens 11. The support plate 61 can be rotated about the shaft 63
against the spring force of the spring 66 to move the image pick-up
unit 21 out of the photographic optical path including the optical
axis O.
The bent portion 123b of the cam plate 123, which is provided with
the rack 123a, is provided at one end thereof closer to the image
pick-up unit 21 with a pusher 123c, which is formed as an extension
of the bent portion 123b. Rotation of the zoom motor 116 in the
direction to retract the zoom lens 11 causes the cam plate 123 to
move toward the retracted position (to the left as viewed in FIG.
4), which causes the tip of the pusher 123c contact and pushes the
upper end 64 of the crank portion 62a of the support plate 61. This
turns the support plate 61 towards its retracted position against
the spring force of the spring 66. Before the cam plate 123 reaches
its retracted position, the image pick-up unit 21 is moved off the
photographing optical path as shown by two-dot chain lines in FIG.
4. The cam plate 123 is provided with a slit 123d in which part
of the image pick-up unit 21 can move so as not to interfere with
the cam plate 123 when it moves to its retracted position.
Rotation of the zoom motor 116 in the retracting direction causes
the rear barrel 104 and the rear lens group L2 to retreat towards
their retracted positions previously occupied by the image pick-up
unit 21 (refer to FIG. 1C).
Rotation of the zoom motor 116 in the advancing direction causes
the rear barrel 104 and the rear lens group L2 to move forwardly,
which causes the cam plate 123 to move towards the telephoto extremity
position thereof, i.e., in a direction apart from the barrel block
101. The movement of the cam plate 123 in this direction moves the
pusher 123c away from the upper end 64 of the crank portion 62a
of the support plate 61. This causes the support plate 61 to turn
towards its photographing position through the spring force of the
spring 66. Further movement of the cam plate 123 causes the image
pick-up unit 21 to move into the photographic optical path, where
the rear barrel 104 and the rear lens group L2 are already absent.
When the cam plate 123 reaches its wide-angle extremity position,
the pusher 123c leaves the upper end 64 of the crank portion 62a.
Consequently, the spring 66 brings the support plate 61 into contact
with the locating pin 67. While the zoom lens 11 is driven to effect
zooming and focusing, the cam plate 123 moves within a range where
its pusher 123c is apart from the upper end 64 of the crank portion
62a, so that the image pick-up unit 21 remains in the photographing
position, where the spring 66 holds the support plate 61 to contact
the locating pin 67.
After the power switch (not shown) of the camera shown in FIG.
4 is turned off, the zoom motor 116 rotates in the retracting direction
to retract the lens barrels 103 and 104. At the same time, the cam
plate 123 slides in the retracting direction. This first turns the
support plate 61 toward its retracted position to move the image
pick-up unit 21 out of the photographing optical path. After the
image pick-up unit 21 moves off the photographing optical path,
the rear barrel 104 moves into the position previously occupied
by the image pick-up unit 21. Consequently, the rear end of the
rear barrel 104 or the rear lens group L2 moves rearwardly to a
position close to the inner surface 13 of the camera body (see FIG.
1 (C)).
As can be understood from the foregoing, according to the digital
camera to which the present invention is applied, when the photographic
lens retreats in the camera body, the image pick-up unit 21, which
is positioned behind the photographic lens, is moved out of the
photographic optical path to secure the space behind the lens in
which the rear end of the photographic lens can further retreat.
It is therefore possible to reduce the thickness of the camera body,
or lengthen the movable lens barrel in order to increase the zoom
ratio.
In each of the first and second embodiments, although the image
pick-up unit 21 is secured to the support plate (41 or 61) which
is pivoted about the shaft (43 or 63) extending parallel to the
optical axis O so as to move the image pick-up unit 21 into and
out of the photographic optical path, the image pick-up unit 21
can be guided in a direction perpendicular to the optical axis so
as to be driven to linearly move into and out of the photographic
optical path.
In each of the first and second embodiments, the zoom lens 11 and
the image pick-up unit 21 can be driven by different motive power
sources.
Obvious changes may be made in the specific embodiments 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. |