U.S. patent application number 09/785185 was filed with the patent office on 2001-08-23 for image-tremble-correcting system for optical instrument.
This patent application is currently assigned to ASAHI KOGAKU KOGYO KABUSHIKI KAISHA. Invention is credited to Sasaki, Takamitsu, Uenaka, Yukio.
Application Number | 20010016116 09/785185 |
Document ID | / |
Family ID | 18562902 |
Filed Date | 2001-08-23 |
United States Patent
Application |
20010016116 |
Kind Code |
A1 |
Sasaki, Takamitsu ; et
al. |
August 23, 2001 |
Image-tremble-correcting system for optical instrument
Abstract
In an image-tremble-correcting system for an optical instrument,
having an optical focussing system for producing a focussed image,
to correct a tremble of the focussed image caused by an oscillation
of the optical instrument, a movable optical tremble-correction
system is assembled in the focussing system of the optical
instrument. An X-Y rectangular coordinate system which is defined
on a plane perpendicular to the optical axis of the focussing
system, the origin of the coordinate system coinciding with the
optical axis of the focussing system, the X- and Y-axes thereof
defining an angle of 45.degree. with a horizontal axis and a
vertical axis defined on the plane when the optical instrument is
positioned at a usual attitude. The movable optical
tremble-correction system being movable along the X-axis and the
Y-axis of the X-Y rectangular coordinate system to the same
extent.
Inventors: |
Sasaki, Takamitsu; (Saitama,
JP) ; Uenaka, Yukio; (Saitama, JP) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN
1941 ROLAND CLARKE PLACE
RESTON
VA
20191
|
Assignee: |
ASAHI KOGAKU KOGYO KABUSHIKI
KAISHA
Tokyo
JP
|
Family ID: |
18562902 |
Appl. No.: |
09/785185 |
Filed: |
February 20, 2001 |
Current U.S.
Class: |
396/55 |
Current CPC
Class: |
G03B 2217/005 20130101;
G03B 2205/0015 20130101; G03B 2205/0069 20130101; G03B 5/00
20130101 |
Class at
Publication: |
396/55 |
International
Class: |
G03B 017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 17, 2000 |
JP |
P2000-039320 |
Claims
1. An image-tremble-correcting system for an optical instrument,
having an optical focussing system for producing a focussed image,
to correct a tremble of said focussed image caused by an
oscillation of said optical instrument, which comprises: a movable
optical tremble-correction system assembled in the optical
focussing system of said optical instrument; an X-Y rectangular
coordinate system which is defined on a geometrical plane
perpendicular to an optical axis of said optical focussing system,
an origin of said X-Y rectangular coordinate system coinciding with
the optical axis of said optical focussing system, the X- and
Y-axes thereof defining an angle of 45.degree. with a horizontal
axis and a vertical axis defined on said geometrical plane when
said optical instrument is positioned at a usual attitude; a first
position-detecting system that detects a position of said movable
optical tremble-correction system along the X-axis of said X-Y
rectangular coordinate system; a second position-detecting system
that detects a position of said movable optical tremble-correction
system along the Y-axis of said X-Y rectangular coordinate system;
a first driving system that moves said movable optical
tremble-correction system along the X-axis of the X-Y rectangular
coordinate system; a second driving system that moves said movable
optical tremble-correction system along the Y-axis of the X-Y
rectangular coordinate system; a tremble-sensor system that detects
an amount of tremble of said focussed image with respect to said
X-Y rectangular coordinate system; and a controller that controls
said first and second driving system to move said movable optical
tremble-correction system along the X- and Y-axes of the X-Y
rectangular coordinate system, such that the amount of tremble of
said focussed image is neutralized.
2. An image-tremble-correcting system as set forth in claim 1,
wherein said movable optical tremble-correction system is movable
along the X-axis and the Y-axis of said X-Y rectangular coordinate
system to a same extent, whereby the movement of the movable
optical treble-correction system is restricted in a square
area.
3. An image-tremble-correcting system as set forth in claim 1,
further comprising: a first limit-position-determination system
that determines whether the position detected by said first
position-detecting system is a first limit position along the
X-axis of said X-Y rectangular coordinate system; a first
correction-limit-determination system that determines whether an
amount of the tremble of said focussed image along the X-axis of
said X-Y rectangular coordinate system exceeds said first limit
position when it is determined by said first
limit-position-determination system that the position detected by
said first position-detecting system is said first limit position
along the X-axis of said X-Y rectangular coordinate system; a
second limit-position-determination system that determines whether
the position detected by said second position-detecting system is a
second limit position along the Y-axis of said X-Y rectangular
coordinate system; and a second correction-limit-determination
system that determines whether an amount of tremble of said
focussed image along the Y-axis of said X-Y rectangular coordinate
system exceeds said second limit position when it is determined by
said second limit-position-determination system that the position
detected by said second position-detecting system is said second
limit position along the Y-axis of said X-Y rectangular coordinate
system, wherein said controller ceases controlling said first
driving system when it is determined by said first
correction-limit-determination system that the amount of tremble of
said focussed image along the X-axis of said X-Y rectangular
coordinate system exceeds said first limit position, and wherein
said controller ceases controlling said second driving system when
it is determined by said second correction-limit-determination
system that the amount of tremble of said focussed image along the
Y-axis of said X-Y rectangular coordinate system exceeds said
second limit position.
4. An image-tremble-correcting system as set forth in claim 1,
wherein said tremble-sensor system includes: a first angular speed
sensor that detects a first angular speed of said optical
instrument around the X-axis of said X-Y rectangular coordinate
system; and a second angular speed sensor that detects a second
angular speed of said optical instrument around the Y-axis of said
X-Y rectangular coordinate system, the controlling of said
respective first and second driving systems by said controller
being performed on the basis of said first and second angular speed
detected by said first and second angular speed sensors.
5. An image-tremble-correcting system as set forth in claim 4,
wherein said respective first and second driving systems comprise a
first electromagnetic driving system and a second electromagnetic
driving system, both a direction and a magnitude of an electric
current, flowing through said first electromagnetic driving system,
being controlled by said controller on the basis of the position of
said movable optical tremble-correction system, detected by said
first position-detecting system, and the first angular speed
detected by said first angular speed sensor, thereby determining
both a direction and an acceleration of the movement of said
movable optical tremble-correction system along the X-axis of said
X-Y rectangular coordinate system, both a direction and a magnitude
of an electric current, flowing through said second electromagnetic
driving system, being controlled by said controller on the basis of
the position of said movable optical tremble-correction system,
detected by said second position-detecting system, and the second
angular speed detected by said second angular speed sensor, thereby
determining both a direction and an acceleration of the movement of
said movable optical tremble-correction system along the Y-axis of
said X-Y rectangular coordinate system.
6. An image-tremble-correcting system as set forth in claim 1,
wherein said optical instrument comprises a single lens reflex
camera having a photographing optical system as said optical
focussing system, and said movable optical tremble-correction
system, said first and second position-detecting systems, and said
first and second driving systems being assembled as an
image-tremble-correcting unit in said photographing optical system.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to an image-tremble-correcting system
for an optical instrument having an image-focussing lens system,
such as a still camera, a video camera, a telescope, a pair of
binoculars or the like, to correct a tremble of a focussed image
caused by an oscillation of the optical instrument due to, for
example, a hand tremble.
[0003] 2. Description of the Related Art
[0004] For example, such an image-tremble-correcting system is
frequently incorporated in a photographing lens system of a single
lens reflex (SLR) type camera. The image-tremble-correcting system
comprises a movable image-tremble-correcting lens system assembled
in the photographing lens system, a tremble sensor system that
detects an amount of tremble of the camera, and therefore a
focussed image, caused by an oscillation of the camera due to, for
example, a hand tremble, and a driving system that moves the
movable image-tremble-correcting lens system to thereby neutralize
the tremble of the focussed image.
[0005] Of course, the movement of the image-tremble-correcting-lens
system is mechanically limited, and thus it is impossible to
correct the tremble of the focussed image beyond the limits of
movement of the image-tremble-correcting-lens system. Although it
is possible to widen the range through which the
image-tremble-correcting-lens system can be moved, widening of the
range is impossible without an increase in bulkiness of the
photographing lens system.
[0006] As is well known, in the SLR camera, an image to be
photographed is observed via a viewfinder system through the
photographing lens system, and the image-tremble-correcting system
is operated when a release switch button is partly depressed, i.e.
when a photometry switch is turned ON to perform a photometry
measurement. Thus, while the image to be photographed is being
observed through the viewfinder in the course of the photometry
measurement, image tremble is corrected.
[0007] During the photometry measurement, the SLR camera is often
panned widely in vertical and/or horizontal directions to frame the
image to be performed. At this time, the
image-tremble-correcting-lens system may easily reach a limit
position due to the wide movement of the SLR camera in the vertical
and/or horizontal directions, resulting in an awkward motion of the
image as observed through the viewfinder system. Of course, the
awkward motion of the image gives a photographer an uncomfortable
feeling.
[0008] Note, the same is true for other optical instruments, such
as a video camera, a telescope, a pair of binoculars or the
like.
SUMMARY OF THE INVENTION
[0009] Therefore, an object of the present invention is to provide
an image-tremble-correcting system for an optical instrument, which
is constituted such that vertical and horizontal limitations of
movement of an image-tremble-correcting-lens system can be widened
without increasing the mechanical bulkiness of a photographing lens
system.
[0010] In accordance with the present invention, there is provided
an image-tremble-correcting system for an optical instrument,
having an optical focussing system for producing a focussed image,
to correct a tremble of the focussed image caused by an oscillation
of the optical instrument. The image-tremble-correcting system
comprises a movable optical tremble-correction system assembled in
the optical focussing system of the optical instrument, and an X-Y
rectangular coordinate system which is defined on a geometrical
plane perpendicular to an optical axis of the optical focussing
system. An origin of the X-Y rectangular coordinate system
coincides with the optical axis of the optical focussing system,
and the X- and Y-axes thereof define an angle of 45.degree. with a
horizontal axis and a vertical axis defined on the geometrical
plane when the optical instrument is positioned at a usual
attitude. The image-tremble-correcting system further comprises a
first position-detecting system that detects a position of the
movable optical tremble-correction system along the X-axis of the
X-Y rectangular coordinate system, a second position-detecting
system that detects a position of the movable optical
tremble-correction system along the Y-axis of the X-Y rectangular
coordinate system, a first driving system that moves the movable
optical tremble-correction system along the X-axis of the X-Y
rectangular coordinate system, a second driving system that moves
the movable optical tremble-correction system along the Y-axis of
the X-Y rectangular coordinate system, a tremble-sensor system that
detects an amount of tremble of the focussed image with respect to
the X-Y rectangular coordinate system, and a controller that
controls the first and second driving system to move the movable
optical tremble-correction system along the X- and Y-axes of the
X-Y rectangular coordinate system, such that the amount of tremble
of the focussed image is neutralized.
[0011] Preferably, the movable optical tremble-correction system is
movable along the X-axis and the Y-axis of the X-Y rectangular
coordinate system to the same extent, such that the movement of the
movable optical tremble-correction system is restricted in a square
area.
[0012] The image-tremble-correcting system may further comprise a
first limit-position-determination system that determines whether
the position detected by the first position-detecting system is a
first limit position along the X-axis of the X-Y rectangular
coordinate system, a first correction-limit-determination system
that determines whether an amount of tremble of the focussed image
along the X-axis of the X-Y rectangular coordinate system exceeds
the first limit position, when it is determined by the first
limit-position-determination system that the position detected by
the first position-detecting system is the first limit position
along the X-axis of the X-Y rectangular coordinate system, a second
limit-position-determination system that determines whether the
position detected by the second position-detecting system is a
second limit position along the Y-axis of the X-Y rectangular
coordinate system, and a second correction-limit-determination
system that determines whether an amount of tremble of the focussed
image along the Y-axis of the X-Y rectangular coordinate system
exceeds the second limit position, when it is determined by the
second limit-position-determination system that the position
detected by the second position-detecting system is the second
limit position along the Y-axis of the X-Y rectangular coordinate
system.
[0013] In this case, the controller ceases controlling the first
driving system when it is determined by the first
correction-limit-determination system that the amount of tremble of
the focussed image along the X-axis of the X-Y rectangular
coordinate system exceeds the first limit position. Similarly, the
controller ceases controlling the second driving system when it is
determined by the second correction-limit-determination system that
the amount of tremble of the focussed image along the Y-axis of the
X-Y rectangular coordinate system exceeds the second limit
position.
[0014] The tremble-sensor system may include a first angular speed
sensor that detects a first angular speed of the optical instrument
around the X-axis of the X-Y rectangular coordinate system, and a
second angular speed sensor that detects a second angular speed of
the optical instrument around the Y-axis of the X-Y rectangular
coordinate system. In this case, the controlling of the respective
first and second driving systems by the controller is performed on
the basis of the first and second angular speed detected by the
first and second angular speed sensors.
[0015] Preferably, the respective first and second driving systems
comprise a first electromagnetic driving system and a second
electromagnetic driving system. In this case, both a direction and
a magnitude of an electric current, flowing through the first
electromagnetic driving system, is controlled by the controller on
the basis of the position of the movable optical tremble-correction
system, detected by the first position-detecting system, and the
first angular speed detected by the first angular speed sensor,
thereby determining both a direction and an acceleration of the
movement of the movable optical tremble-correction system along the
X-axis of the X-Y rectangular coordinate system. Similarly, both a
direction and a magnitude of an electric current, flowing through
the second electromagnetic driving system, is controlled by the
controller on the basis of the position of the movable optical
tremble-correction system, detected by the second
position-detecting system, and the second angular speed detected by
the second angular speed sensor, thereby determining both a
direction and an acceleration of the movement of the movable
optical tremble-correction system along the Y-axis of the X-Y
rectangular coordinate system.
[0016] For example, the optical instrument may comprise a single
lens reflex camera having a photographing optical system as the
optical focussing system. In this case, preferably, the movable
optical tremble-correction system, the first and second
position-detecting systems, and the first and second driving
systems are assembled as an image-tremble-correcting unit in the
photographing optical system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The object and other objects of the present invention will
be better understood from the following description, with reference
to the accompanying drawings, in which:
[0018] FIG. 1 is a schematic longitudinal sectional view showing a
part of a single lens reflex (SLR) type camera, in which an
image-tremble-correcting system according to the present invention
is embodied;
[0019] FIG. 2 is a view showing an X-Y rectangular coordinate
system defined on a geometrical plane perpendicular to an optical
axis of a photographing lens system of the SLR camera such that an
image-tremble-correcting lens system is movable along the X- and
Y-axes thereof, the X- and Y-axes of the X-Y coordinate system
defining an angle of 45.degree. with a horizontal axis and a
vertical axis, which are defined on the geometrical plane when the
SLR camera is held by hand at a usual photographing attitude;
[0020] FIG. 3 is a perspective view showing a positional
relationship between an image-tremble-correcting unit and a frame
of photographic film;
[0021] FIG. 4 is an exploded view showing the
image-tremble-correcting unit;
[0022] FIG. 5 is a front view showing an assembly of an annular
plate body and a movable plate frame of the
image-tremble-correcting unit;
[0023] FIG. 6 is a front view showing the movable plate frame of
the image-tremble-correcting unit;
[0024] FIG. 7 is a block diagram of the SRL camera partially
illustrated in FIG. 1;
[0025] FIG. 8 is a flowchart of a part of an
image-tremble-correcting routine;
[0026] FIG. 9 is a flowchart of another part of the
image-tremble-correcting routine; and
[0027] FIG. 10 is a flowchart of the remainder of the
image-tremble-correcting routine.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] FIG. 1 partially and schematically shows a lens barrel of a
single lens reflex (SLR) type camera, in which an
image-tremble-correcting system according to the present invention
is embodied. In this drawing, a camera body of the camera is
indicated by reference 1, and the lens barrel is indicated by
reference 9.
[0029] The lens barrel 9 contains a photographing optical system,
generally indicated by reference 2, and the photographing optical
system 2 includes a first group of lenses L1, a second group of
lenses L2, and a third group of lenses L3. The first and third
groups of lenses L1 and L3 form a photographing lens system having
an optical axis O. The second group of lenses L2 serves as an
image-tremble-correcting lens system, which is movable along a
geometrical plane perpendicular to the optical axis O of the
photographing lens system (L1 and L3). Namely, an X-Y rectangular
coordinate system is defined on the aforesaid geometrical plane
such that the origin thereof coincides with the optical axis O of
the photographing lens system (L1 and L3), and the
image-tremble-correcting lens system (L2) is movable along the
X-axis and the Y-axis of the X-Y rectangular coordinate system.
[0030] As shown in FIG. 2, the X-Y rectangular coordinate system is
set such that the X- and Y-axes thereof define an angle of
45.degree. with a horizontal axis HA and a vertical axis VA, which
are defined on the aforesaid geometrical plane when the camera is
held by hand at a usual photographing attitude such that a central
lengthwise axis of a rectangular frame of photographic film, which
is positioned at an image plane defined by the photographing lens
system (L1 and L3), is horizontally oriented.
[0031] During a photographing operation, when an image to be
photographed is subjected to a tremble caused by an oscillation of
the camera due to, for example, a hand tremble, the
image-tremble-correcting lens system (L2) is moved along the X- and
Y-axes of the X-Y rectangular coordinate system such that the
tremble of the image to be photographed is neutralized, whereby the
image to be photographed remains still despite the oscillation of
the camera.
[0032] In FIG. 2, an amount of movement of the
image-tremble-correcting lens system (L2) along the X-axis of the
X-Y rectangular coordinate system is represented by an X coordinate
"a", and an amount of movement of the image-tremble-correcting lens
system (L2) along the Y-axis of the X-Y rectangular coordinate
system is represented by a Y coordinate "b". In this embodiment, as
mentioned hereinafter, each absolute value of the X and Y
coordinates "a" and "b" is mechanically limited to a maximum value
"r", and thus the movement of the image-tremble-correcting lens
system (L2) is restricted in a square area SA with four sides
having a length of "2r", as shown in FIG. 2.
[0033] Therefore, when the camera is held by hand at the usual
photographing attitude, a maximum range R, in which the
image-tremble-correcting lens system (L2) can be moved along each
of the horizontal axis HA and the vertical axis VA, is defined by
the following formula:
R=(8r.sup.2).sup.1/2
[0034] In order to systematically move the image-tremble lens
system (L2) along the X- and Y-axes of the X-Y coordinate system,
the image-tremble-correcting lens system (L2) is integrally and
securely held in a barrel frame 14, and is assembled in an
image-tremble-correcting unit 10.
[0035] As shown in FIGS. 3 and 4, the image-tremble-correcting unit
10 includes an annular plate body 11 having a circular opening 11a
formed therein, and the annular plate body 11 is immovably
supported by the lens barrel 9. Namely, as shown in FIG. 1, an
inner ring element 9b is integrally protruded from an inner surface
of the lens barrel 9, and the annular plate body 11 is securely
attached to the inner ring element 9b by screws represented by 9a.
As best shown in FIG. 4, the annular plate body 11 is integrally
formed with two spacer block elements 11.sub.1 and 11.sub.2 which
are diametrically arranged at the circumference of the annular
plate body 11.
[0036] The image-tremble-correcting unit 10 also includes a
generally annular yoke plate 12 having a circular opening 12a
formed therein, and the annular yoke plate 12 is securely attached
to the spacer block elements 11.sub.1 and 11.sub.2 by screws 13.
The circular openings 11a and 12a are coaxially aligned with each
other, and have a central axis which coincides with the optical
axis O of the photographing lens system (L1 and L3).
[0037] The image-tremble-correcting unit 10 further includes a
movable plate frame 15 having a circular opening 15a formed
therein, and the movable plate frame 15 securely supports the
barrel frame 14 holding the image-tremble-correcting lens system
(L2). The barrel frame 14 is integrally formed with an annular
flange 14a (FIG. 1), and the annular flange 14a of the barrel frame
14 is fixed to an annular rim of the circular opening 15a of the
movable plate frame 15, with the barrel frame 14 passing through
the circular opening 15a, as best shown in FIG. 4.
[0038] The movable plate frame 15 is movably received in a space
between the annular plate body 11 and the annular yoke plate 12,
such that the movable plate frame 15, and therefore the lens system
(L2), can be moved along the X- and Y-axes of the X-Y coordinate
system, as explained in detail hereinafter.
[0039] In FIG. 3, reference F indicates a rectangular frame of
photographic film which is positioned at the image plane defined by
the photographing lens system (L1 and L3). When the X-Y coordinate
system is projected onto the photographic film frame F, as shown in
FIG. 3, the X- and Y-axes thereof form an angle of 45.degree. with
a central lengthwise axis CLA of the photographic film frame F.
Thus, when the horizontal and vertical axes HA and VA (FIG. 2) are
projected onto the photographic film frame F provided that the
camera is held by hand at the usual photographing attitude, the
horizontal axis HA coincides with the central lengthwise axis CLA
of the photographic film frame F.
[0040] As shown in FIG. 4, an L-shaped movable member 24 is
arranged between the annular plate body 11 and the movable plate
frame 15, and has two arms 24a and 24b which form a right angle.
The arm 24a is provided with a pair of ring-like guide rollers 25
rotatably attached to a side face directed toward the movable plate
frame 15, and the arm 24b is provided with a pair of ring-like
guide rollers 26 rotatably attached to a side face directed toward
the annular plate body 11.
[0041] On the other hand, as shown in FIGS. 4, 5 and 6, a pair of
elongated guide slots 15f is formed in the movable plate frame 15,
and the elongated guide slots 15f are aligned with each other along
the X-axis of the X-Y coordinate system. Also, a pair of elongated
guide slots 11d is formed in the annular plate body 11, as shown in
FIG. 4, and the elongated guide slots 11d are aligned with each
other along the Y-axis of the X-Y coordinate system.
[0042] When the parts 11, 12 and 15 are assembled as in FIG. 3, the
two respective ring-like guide rollers 25 are slidably received in
the elongated guide slots 15f, as best shown in FIGS. 5 and 6, and
the two respective ring-like guide rollers 26 are slidably received
in the elongated guide slots 11d. Thus, the movable plate frame 15
can moved along the X- and Y-axes of the X-Y coordinate system.
[0043] As shown in FIG. 4, an L-shaped plate element 20 is securely
attached to an inner wall of the annular plate body 11 by three
screws 21, and has two arm sections 20a and 20b which form a right
angle. The arm section 20a extends along the Y-axis of the X-Y
coordinate system, and the arm section 20b extends along the X-axis
of the X-Y coordinate system. A first pair of elongated permanent
magnets 22a is fixed on the arm section 20a to extend along the
Y-axis of the X-Y coordinate system, and a second pair of elongated
permanent magnets 22b is fixed on the arm section 20b to extend
along the X-axis of the X-Y coordinate system.
[0044] On the other hand, the movable plate frame 15 is provided
with a first electromagnetic coil 16a and a second electromagnetic
coil 16b securely supported thereby, and the respective first and
second electromagnetic coils 16a and 16b are aligned with the first
and second pairs of elongated permanent magnets 22a and 22b along
the optical axis O of the photographing lens system (L1 and
L3).
[0045] When the parts 11, 12 and 15 are assembled as in FIG. 3, the
first electromagnetic coil 16a is associated with the first pair of
permanent magnets 22a to form a first driving system that moves the
movable plate frame 15, and therefore the lens system (L2), along
the X-axis of the X-Y coordinate system, and the second
electromagnetic coil 16b is associated with the second pair of
permanent magnets 22b to form a second driving system that moves
the movable plate frame 15, and therefore the lens system (L2),
along the Y-axis of the X-Y coordinate system.
[0046] In particular, when the first electromagnetic coil 16a is
electrically energized in a magnetic field produced by the first
pair of permanent magnets 22a, it is subjected to a driving force
in accordance with Fleming's rule, such that the movable plate
frame 15, and therefore the lens system (L2), is moved along the
X-axis of the X-Y coordinate system. Similarly, when the second
electromagnetic coil 16b is electrically energized in a magnetic
field produced by the second pair permanent magnets 22b, it is
subjected to a driving force in accordance with Fleming's rule,
such that the movable plate frame 15, and therefore the lens system
(L2), is moved along the Y-axis of the X-Y coordinate system. Of
course, the direction of the driving force, to which each coil
(16a, 16b) is subjected, depends on the direction in which electric
current flows through each coil (16a, 16b), and the magnitude of
the driving force depends on the amount of electric current flowing
through each coil (16a, 16b).
[0047] As shown in FIGS. 4, 5 and 6, the movable plate frame 15 has
a first infrared LED (light emitting diode) 19a and a second
infrared LED (light emitting diode) 19b securely attached thereto.
The first infrared LED 19a is arranged on the diametrical opposite
side of the first electromagnetic coil 16a with respect to the
circular opening 15a, and the second infrared LED 19b is arranged
on the diametrical opposite side of the second electromagnetic coil
16b with respect to the circular opening 15a.
[0048] On the other hand, as shown in FIG. 4, the annular plate
body 11 has a first PSD (position sensitive device) 30a and a
second PSD 30b securely attached thereto. The first PSD 30a is
arranged on the diametrical opposite side of the first pair of
permanent magnets 22a with respect to the circular opening 11a, and
the second PSD 30b is arranged on the diametrical opposite side of
the second pair of permanent magnets 22b with respect to the
circular opening 11a. Note, each of the first and second PSD's 30a
and 30b is formed as a one-dimensional or linear PSD.
[0049] When the parts 11, 12 and 15 are assembled as in FIG. 3, the
first infrared LED 19a is associated with the first PSD 30a to form
a first position-detecting system that detects a position of the
movable plate frame 15, and therefore the lens system (L2), along
the X-axis of the X-Y coordinate system. Similarly, the second
infrared LED 19b is associated with the second PSD 30b to form a
second position-detecting system that detects a position of the
movable plate frame 15, and therefore the lens system (L2), along
the Y-axis of the X-Y coordinate system.
[0050] In particular, the movable plate frame 15 is formed with a
first fine slit (not visible in FIGS. 4, 5 and 6) which extends
along the Y-axis of the X-Y coordinate system, and infrared light,
emitted from the first infrared LED 19a, is made incident on the
first PSD 30a through the first fine slit. Namely, the infrared
light emitted from the first infrared LED 19a is formed into a
sheet-like infrared light beam by the first fine slit, and the
sheet-like infrared light beam is made incident on the first PSD
30a. An incident position, at which the sheet-like infrared light
is made incident on the first PSD 30a, is shifted in accordance
with the movement of the movable plate frame 15, and therefore the
lens system (L2), along the X-axis of the X-Y coordinate system,
and the output electric current from the first PSD 30a varies in
accordance with the shift of the incident position. Thus, by
detecting the variation of the output electric current of the first
PSD 30a, it is possible to detect the position of the movable plate
frame 15, and therefore the lens system (L2), along the X-axis of
the X-Y coordinate system.
[0051] Similarly, the movable plate frame 15 is formed with a
second fine slit (not visible in FIGS. 4, 5 and 6) which extends
along the X-axis of the X-Y coordinate system, and infrared light,
emitted from the second infrared LED 19b, is made incident on the
second PSD 30b through the second fine slit. Namely, the infrared
light emitted from the second infrared LED 19b is formed into a
sheet-like infrared light beam by the second fine slit, and the
sheet-like infrared light beam is made incident on the second PSD
30b. An incident position, at which the sheet-like infrared light
is made incident on the second PSD 30b, is shifted in accordance
with the movement of the movable plate frame 15, and therefore the
lens system (L2), along the Y-axis of the X-Y coordinate system,
and the output electric current from the second PSD 30b varies in
accordance with the shift of the incident position. Thus, by
detecting the variation of the output electric current of the
second PSD 30b, it is possible to detect the position of the
movable plate frame 15, and therefore the lens system (L2), along
the Y-axis of the X-Y coordinate system.
[0052] As shown in FIGS. 4, 5 and 6, the movable plate frame 15 is
provided with first, second and third stopper members 15.sub.1,
15.sub.2 and 15.sub.3 to restrict the movement of the movable plate
frame 15, and therefore the lens system (L2), along the X- and
Y-axes of the X-Y coordinate system. In particular, the first
stopper member 15.sub.1 is associated with ends of the first and
second electromagnetic coils 16a and 16b which are adjacent to each
other, and the respective second and third stopper members 15.sub.2
and 15.sub.3 are associated with the other ends of the first and
second electromagnetic coils 16a and 16b which are away from the
respective adjacent ends thereof. The first stopper member 15.sub.1
has two rounded end faces 15c and 15e, and the second and third
stopper members 15.sub.2 and 15.sub.3 have rounded end faces 15b
and 15d, respectively. The rounded end faces 15b and 15a are
opposite to each other along the X-axis of the X-Y coordinate
system, and the rounded end faces 15d and 15e are opposite to each
other along the Y-axis of the X-Y coordinate system.
[0053] On the other hand, as best shown in FIG. 4, the annular yoke
plate 12 is formed with a first set of edges 12b and 12c, opposite
to each other along the X-axis of the X-Y coordinate system, and a
second set of edges 12d and 12e opposite to each other along the
Y-axis of the X-Y coordinate system.
[0054] When the parts 11, 12 and 15 are assembled as in FIG. 3, the
rounded end faces 15b and 15c are operated in conjunction with the
first set of edges 12b and 12c, such that the movement of the
movable plate frame 15, and therefore the lens system (L2), is
restricted to a distance value of 2.times.r along the X-axis of the
X-Y coordinate system, as shown in FIG. 2. Similarly, the rounded
end faces 15d and 15e are operated in conjunction with the second
set of edges 12d and 12e, such that the movement of the movable
plate frame 1S, and therefore the lens system (L2), is restricted
to a distance value of 2.times.r along the Y-axis of the X-Y
coordinate system, as shown in FIG. 2. In short, the movement of
the image-tremble-correcting lens system (L2) is restricted to the
square area SA shown in FIG. 2.
[0055] FIG. 7 shows a block diagram of the camera partially
illustrated in FIG. 1. As shown in this drawing, a system
controller 8 is provided in the camera body 1, and is constituted
as a microcomputer comprising a central processing unit (CPU), a
read-only memory (ROM) for storing programs and constants, a
random-access memory (RAM) for storing temporary data, and an
input/output interface circuit (I/O). Of course, the system
controller is used to control the camera as a whole.
[0056] When the lens barrel 9 (FIG. 1) is mounted on a mount (not
shown) of the camera body 1, the image-tremble-correcting unit 10
is electrically connected to the system controller 8, as shown in
FIG. 7. To this end, as shown in FIG. 4, a first flexible printed
circuit sheet 50 is led into the movable plate frame 15, and a
second flexible printed circuit sheet 60 is led into the annular
plate body 11. The first and second flexible printed circuit sheets
50 and 60 are extended to an electric connector (not shown),
provided in a terminal end of the lens barrel 9, which is coupled
to an electric connector provided in the mount of the camera body 1
when the lens barrel 9 is mounted on the mount of the camera body
1.
[0057] As best shown in FIG. 5, a portion of the first flexible
printed circuit sheet 50, led into the movable plate frame 15,
branches into first and second sections 51 and 52. A pair of
terminal pins of the first infrared LED 19a is soldered to a
circuit pattern formed on the second section 52, and a pair of
electric lead lines 53, extending from the second electromagnetic
coil 16b, is soldered to another circuit pattern formed on the
second section 52. Similarly, a pair of terminal pins of the second
infrared LED 19b is soldered to a circuit pattern formed on the
first section 51, and a pair of electric lead lines 54, extending
from the first electromagnetic coil 16a, is soldered to another
circuit pattern formed on the first section 51.
[0058] Although not visible in FIG. 4, a portion of the second
flexible printed circuit sheet 60, led into the annular plate body
11, also branches into first and second sections. Terminal pins of
the first PSD 30a are soldered to a circuit pattern formed on the
first section, and terminal pins of the second PSD 30b are soldered
to a circuit pattern formed on the second section.
[0059] In short, when the lens barrel 9 is mounted on the mount of
the camera body 1, the aforesaid electric connectors are coupled to
each other, thereby establishing the electrical connection between
the system controller 8 and the image-tremble-correcting unit 10,
as shown in FIG. 7.
[0060] Although not shown in FIG. 1, a tremble sensor unit for
sensing a tremble of the camera is suitably assembled in the lens
barrel 9. In FIG. 7, the tremble sensor unit is indicated by
reference 7, and includes a first angular speed sensor 7a for
detecting an angular speed around the X-axis of the X-Y coordinate
system, and a second angular speed sensor 7b for detecting an
angular speed around the Y-axis of the X-Y coordinate system. When
the lens barrel 9 is mounted on the mount of the camera body 1, the
tremble sensor unit 7 is also electrically connected to the system
controller 8, as shown in FIG. 7. Note, each of the first and
second angular speed sensors 7a and 7b may be formed as an
gyro-type angular speed sensor.
[0061] As shown in FIG. 7, the camera has a release switch button
(R/B) 70 provided at a suitable location on the camera body 1. As
well known, in the single lens reflex (SLR) type camera, the
release switch button 70 is associated with both a photometry
switch (P-SW) 70a and a release switch (R-SW) 70b. When the release
switch button 70 is partly depressed, the photometry switch 70a is
turned ON, and, when the release switch button 70 is fully
depressed, the release switch 70b is turned ON.
[0062] The photometry switch 70a is associated with a photometry
circuit (not shown), including a photometry sensor, operated under
control of the system controller 8. When the photometry switch 70a
is turned ON by partly depressing the release switch button 70, the
photometry circuit is operated to detect a quantity of light,
reflected from an image to be photographed. Simultaneously, both
the tremble sensor unit 7 and the image-tremble-correcting unit 10
are operated to correct a tremble of the image to be photographed,
which is caused by an oscillation of the camera due to, for
example, a hand tremble.
[0063] As is well known, in the SRL camera, the release switch 70b
is associated with a mirror drive mechanism (not shown) for driving
a quick-return mirror and a focal-plane shutter drive mechanism
(not shown) for driving a leading shutter curtain and a trailing
shutter curtain. When the release switch 70b is turned ON by fully
depressing the release switch button 70, both the mirror drive
mechanism and the focal-plane shutter drive mechanism are operated
to perform a photographing exposure operation. The operation of
both the tremble sensor unit 7 and the image-tremble-correcting
unit 10 is continued until the photographing exposure operation is
completed.
[0064] FIGS. 8, 9 and 10 show a flowchart of an
image-tremble-correcting routine executed in the system controller
8. Note, the execution of the routine is started by turning ON the
photometry switch 70a, and execution of the routine comprising
steps 802 to 828 is repeated at suitable regular short time
intervals of, for example, 1 ms, as long as the photometry switch
70a is turned ON.
[0065] At step 801, a first variable "AVX" and a second variable
"AVY" are initialized to "0". The first variable "AVX" represents a
relative angular position of the X-axis of the X-Y coordinate
system, and the second variable "AVY" represents a relative angular
position of the Y-axis of the X-Y coordinate system. Namely, both
the first and second variables "AVX and "AVY" represent a relative
angular position of the X-Y coordinate system (i.e. the camera). In
short, when the photometry switch 70a is turned ON, the position of
the X-Y coordinate system (i.e. the camera) is set as the initial
angular position (AVX=0 and AVY=0). Note, the first and second
variables "AVX and "AVY" are previously defined in the ROM of the
system controller 8.
[0066] At step 802, a first angular speed data "ASX" is retrieved
from the first angular speed sensor 7a, and a second angular speed
data "ASY" is retrieved from the second angular speed sensor 7b.
The respective first and second angular speed data "ASX" and "ASY"
represent angular speeds around the X- and Y-axes of the X-Y
coordinate system, which are caused by an oscillation of the camera
due to, for example, a hand tremble. Namely, both the first and
second angular speed data "ASX" and "ASY" represent a magnitude of
the oscillation of the camera, and therefore, the tremble of an
image to be photographed. Note, the first and second angular speed
data "ASX" and "ASY" are temporary stored in the RAM of the system
controller 8.
[0067] At step 803, a first angular displacement data ".DELTA.AX"
is calculated from the first angular speed data "ASX" with respect
to the X-axis of the X-Y coordinate system, and a second angular
displacement data ".DELTA.AY" is calculated from the second angular
speed data "ASY" with respect to the Y-axis of the X-Y coordinate
system. Then, at step 804, the following calculations are
performed:
AVX.fwdarw.AVX+.DELTA.AX
AVY.fwdarw.AVY+.DELTA.AY
[0068] Both the calculated results "AVX" and "AVY" represent a
relative angular displacement of the X-Y coordinate system (i.e.
the camera) in the plane defined by the X- and Y-axes of the X-Y
coordinate system, which is measured from the last angular position
of the X-Y coordinate system. Namely, the first variable "AVX"
represents a relative angular position of the X-axis of the X-Y
coordinate system with respect to the last angular position of the
X-axis thereof, and the second variable "AVY" represents a relative
angular position of the Y-axis of the X-Y coordinate system with
respect to the last angular position of the Y-axis thereof. Note
that, of course, the initially-calculated results "AVX" and "AVY"
represent a relative angular position of the X-Y coordinate system
with respect to the initial angular position thereof (AVX=0 and
AVY=0).
[0069] At step 805, an X-component DX.sub.1 of the angular
displacement of the X-axis of the X-Y coordinate system is
calculated from the calculated result "AVX", and a Y-component
DY.sub.1 of the angular displacement of the Y-axis of the X-Y
coordinate system is calculated from the calculated result "AVY".
Note, the respective X-component DX.sub.1 and Y-component DY.sub.1
are temporary stored as X-displacement data and Y-displacement data
in the RAM of system controller 8.
[0070] At step 806, X-position data DX.sub.2 is retrieved from the
first PSD 30a, and Y-position data DY.sub.2 is retrieved from the
second PDS 30b. Note, the X-position data and Y-position data are
temporarily stored in the RAM of the system controller 8.
[0071] At step 807, a difference .DELTA.DX is calculated as
follows:
.DELTA.DX.fwdarw.DX.sub.2-DX.sub.1
[0072] Then, at step 808, it is determined whether the difference
.DELTA.DX is equal to "0". If .DELTA.DX=0, i.e. if there is
substantially no tremble of the image to be photographed along the
X-axis of the X-Y coordinate system, the control proceeds to step
809, in which a drive variable DVX is set to "0". Note, the drive
variable DVX is used to determine an magnitude of an electric
current flowing through the first electromagnetic coil 16a. Of
course, when the setting of "0" is given to the drive variable DVX,
the electric current cannot flow through the first electromagnetic
coil 16a, i.e. the lens system (L2) cannot be moved along the
X-axis of the X-Y coordinate system.
[0073] At step 808, if .DELTA.DX.noteq.0, the control proceeds to
step 810, in which it is determined whether the difference
.DELTA.DX is negative or positive. If the difference .DELTA.DX is
positive, i.e. if the lens system (L2) should be moved toward the
negative side along the X-axis of the X-Y coordinate system
(DX.sub.2>DX.sub.1), the control proceeds to step 811, in which
it is determined whether the X-position data DX.sub.2 is equivalent
to the negative limit position (-r).
[0074] If .DELTA.DX>0 (step 810), and if DX.sub.2=-r (step 811),
this means that the X-displacement data DX.sub.1 is smaller than
"-r", i.e. that the X-displacement data DX.sub.1 (i.e. the amount
of tremble of the image) exceeds the negative limit of correction
(-r). Thus, the control proceeds from step 811 to step 809, in
which the drive variable DVX is set to "0", thereby prohibiting the
movement of the lens system (L2) along the X-axis of the X-Y
coordinate system.
[0075] At step 811, if DX.sub.2 .noteq.-r, i.e. if DX.sub.2>-r,
the control proceeds to step 812, in which a flag XF is set to "1".
Note, the flag XF indicates a direction in which an electric
current should flow through the first electromagnetic coil 16a.
Namely, if XF =0, the electric current flows through the first
electromagnetic coil 16a so that the lens system (L2) is moved
toward the positive side along the X-axis of the X-Y coordinate
system, and if XF 1, the electric current flows through the first
electromagnetic coil 16a so that the lens system (L2) is moved
toward the negative side along the X-axis of the X-Y coordinate
system.
[0076] At step 813, the drive variable DVX is set to an absolute
value of the difference .DELTA.DX. Then, at step 814, the first
electromagnetic coil 16a is electrically energized in accordance
with the value of the flag XF and the value of the drive variable
DVX. In particular, the electric current flows through the first
electromagnet coil 16a in the direction indicated by the flag
XF(=1), so that the lens system (L2) is moved toward the negative
side along the X-axis of the X-Y coordinate system, and the
magnitude of the electric current is determined by the value
.vertline..DELTA.DX.vertline. of the drive variable DVX. Of course,
the larger the magnitude of the electric current, the higher the
acceleration of the lens system (L2).
[0077] At step 810, if the difference .DELTA.DX is negative, i.e.
if the lens system (L2) should be moved toward the positive side
along the X-axis of the X-Y coordinate system
(DX.sub.2<DX.sub.1), the control proceeds to step 815, in which
it is determined whether the X-position data DX.sub.2 is equivalent
to the positive limit position (+r).
[0078] If .DELTA.DX<0 (step 810), and if DX.sub.2=+r (step 815),
this means that the X-displacement data DX.sub.1 is larger than
"+r", i.e. that the X-displacement data DX.sub.1 (i.e. the amount
of tremble of the image along the X-axis of the Y-coordinate
system) exceeds the positive limit of correction (+r). Thus, the
control proceeds from step 815 to step 809, in which the drive
variable DVX is set to "0", thereby prohibiting the movement of the
lens system (L2) along the X-axis of the X-Y coordinate system.
[0079] At step 815, if DX.sub.2.noteq.+r, i.e. if DX.sub.2<+r,
the control proceeds to step 816, in which the flag XF is set to
"0". Then, at step 813, the drive variable DVX is set to an
absolute value of the difference .DELTA.DX, and at step 814, the
first electromagnetic coil 16a is electrically energized in
accordance with the value of the flag XF and the value of the drive
variable DVX. Namely, the electric current flows through the first
electromagnet coil 16a in the direction indicated by the flag
XF(=0), so that the lens system (L2) is moved toward the positive
side along the X-axis of the X-Y coordinate system, and the
magnitude of the electric current is determined by the value
.vertline..DELTA.DX.vertline. of the drive variable DVX.
[0080] At step 817, a difference .DELTA.DY is calculated as
follows:
.DELTA.DY.fwdarw.DY.sub.2-DY.sub.1
[0081] Then, at step 818, it is determined whether the difference
.DELTA.DY is equal to "0". If .DELTA.DY=0, i.e. if there is
substantially no tremble of the image to be photographed along the
Y-axis of the X-Y coordinate system, the control proceeds to step
819, in which a drive variable DVY is set to "0". Note, the drive
variable DVY is used to determine an magnitude of an electric
current flowing through the second electromagnetic coil 16b. Of
course, when the setting of "0" is given to the drive variable DVY,
the electric current cannot flow through the second electromagnetic
coil 16b, i.e. the lens system (L2) cannot be moved along the
Y-axis of the X-Y coordinate system.
[0082] At step 818, if .DELTA.DY.noteq.0, the control proceeds to
step 820, in which it is determined whether the difference
.DELTA.DY is negative or positive. If the difference .DELTA.DY is
positive, i.e. if the lens system (L2) should be moved toward the
negative side along the Y-axis of the X-Y coordinate system
(DY.sub.2>DY.sub.1), the control proceeds to step 821, in which
it is determined whether the Y-position data DY.sub.2 is equivalent
to the negative limit position (-r).
[0083] If .DELTA.DY>0 (step 820), and if DY.sub.2=-r (step 821),
this means that the Y-displacement data DY.sub.1 is smaller than
"-r", i.e. that the Y-displacement data DY.sub.1 (i.e. the amount
of tremble of the image along the Y-axis of the Y-coordinate
system) exceeds the negative limit of correction (-r). Thus, the
control proceeds from step 821 to step 819, in which the drive
variable DVY is set to "0", thereby prohibiting the movement of the
lens system (L2) along the Y-axis of the X-Y coordinate system.
[0084] At step 821, if DY.sub.2.noteq.-r, i.e. if DY.sub.2>-r,
the control proceeds to step 822, in which a flag YF is set to "1".
Note, the flag YF indicates a direction in which an electric
current should flow through the second electromagnetic coil 16b.
Namely, if YF=0, the electric current flows through the second
electromagnetic coil 16b so that the lens system (L2) is moved
toward the positive side along the Y-axis of the X-Y coordinate
system, and if YF=1, the electric current flows through the second
electromagnetic coil 16b so that the lens system (L2) is moved
toward the negative side along the Y-axis of the X-Y coordinate
system.
[0085] At step 823, the drive variable DVY is set to an absolute
value of the difference .DELTA.DY. Then, at step 824, the second
electromagnetic coil 16b is electrically energized in accordance
with the value of the flag YF and the value of the drive variable
DVY. In particular, the electric current flows through the second
electromagnet coil 16b in the direction indicated by the flag
YF(=1), so that the lens system (L2) is moved toward the negative
side along the Y-axis of the X-Y coordinate system, and the
magnitude of the electric current is determined by the value
.vertline..DELTA.DY.vertline. of the drive variable DVY. Of course,
the larger the magnitude of the electric current, the higher the
acceleration of the lens system (L2).
[0086] At step 820, if the difference .DELTA.DY is negative, i.e.
if the lens system (L2) should be moved toward the positive side
along the Y-axis of the X-Y coordinate system
(DY.sub.2<DY.sub.1), the control proceeds to step 825, in which
it is determined whether the Y-position data DY.sub.2 is equivalent
to the positive limit position (+r).
[0087] If .DELTA.DY<0 (step 820), and if DY.sub.2=+r (step 825),
this means that the Y-displacement data DY.sub.1 is larger than
"+r", i.e. that the Y-displacement data DY.sub.1 (i.e. the amount
of tremble of the image along the Y-axis of the Y-coordinate
system) exceeds the positive limit of correction (+r). Thus, the
control proceeds from step 825 to step 819, in which the drive
variable DVY is set to "0", thereby prohibiting the movement of the
lens system (L2) along the Y-axis of the X-Y coordinate system.
[0088] At step 825, if DY.sub.2.noteq.+r, i.e. if DY.sub.2<+r,
the control proceeds to step 826, in which the flag YF is set to
"0". Then, at step 823, the drive variable DVY is set to an
absolute value of the difference .DELTA.DY, and at step 824, the
second electromagnetic coil 16b is electrically energized in
accordance with the value of the flag YF and the value of the drive
variable DVY. Namely, the electric current flows through the second
electromagnet coil 16b in the direction indicated by the flag
YF(=0), so that the lens system (L2) is moved toward the positive
side along the Y-axis of the X-Y coordinate system, and the
magnitude of the electric current is determined by the value
.vertline..DELTA.DY.vertline. of the drive variable DVY.
[0089] At step 827, it is determined whether the release switch 70b
has been turned ON, i.e. whether the release switch button 70 has
been fully depressed. If the turn-ON of the release switch 70b is
not confirmed, the control proceeds to step 828, in which it is
determined whether the photometry switch 70a is still turned ON. If
the photometry switch 70a is still turned ON, the control returns
to step 802, and thus a tremble of an image to be photographed is
repeatedly corrected as long as the photometry switch 70a is turned
ON.
[0090] At step 827, when it is confirmed that the release switch
70b is turned ON, the control proceeds to step 829, in which an
photographing operation routine (not shown) is executed. In the
execution of the photographing operation routine, the aforesaid
mirror drive mechanism and focal-plane shutter drive mechanism are
operated to perform a photographing exposure operation. Then, at
step 830, it is determined whether the photographing exposure
operation has been completed. If the photographing
exposure-operation is not completed, the control returns to step
802, whereby a tremble of an image to be photographed is repeatedly
corrected until the photographing exposure operation is
completed.
[0091] At step 830, when the completion of the photographing
exposure operation is confirmed, the control proceeds to step 831,
in which the drive variables DVX and DVY are set to "0", thereby
prohibiting the electrical energization of the first and second
electromagnetic coils 16a and 16b. Thereafter, the
image-tremble-correction routine ends.
[0092] At step 828, when it is confirmed that the photometry switch
70a is turned OFF, i.e. when the release switch button 70 is
released from the depression without fully depressing the release
switch button 70, the control proceeds from step 828 to step 831,
in which the drive variables DVX and DVY are set to "0", thereby
prohibiting the electrical energization of the first and second
electromagnetic coils 16a and 16b. Thereafter, the
image-tremble-correction routine ends.
[0093] As is apparent from the foregoing, according to the present
invention, since the X-Y rectangular coordinate system is set such
that the X- and Y-axes thereof define the angle of 45.degree. with
the horizontal axis HA and the vertical axis VA (FIG. 2), it is
possible to widen the vertical and horizontal limitations of the
lens system (L2) without increasing the mechanical bulkiness of the
lens barrel 9. Namely, if the X-Y rectangular coordinate system is
defined such that the X- and Y-axes thereof extend horizontally and
vertically, the movement of the lens system (L2) is restricted in a
square area SA' as shown in FIG. 2, and thus a maximum range, in
which the lens system (L2) can be moved along each of the
horizontal axis HA and the vertical axis VA, is limited by a
distance of "2r", which is shorter than the aforesaid distance of
R=(8r.sup.2).sup.1/2. In short, according to the present invention,
it is possible to widen vertical and horizontal limitations of
movement of the lens system (L2) to about 1.4 times in comparison
with the case of the square area SA'.
[0094] In the aforesaid embodiment, although the
image-tremble-correcting system is incorporated in the single lens
reflex (SLR) type camera, it should be understood that the present
invention may be embodied in another optical instrument, such as a
video camera, a telescope, a pair of binoculars or the like.
[0095] Finally, it will be understood by those skilled in the art
that the foregoing description is of a preferred embodiment of the
system, and that various changes and modifications may be made to
the present invention without departing from the spirit and scope
thereof.
[0096] The present disclosure relates to subject matters contained
in Japanese Patent Applications No. 2000-039320 (filed on Feb. 17,
2000) which is expressly incorporated herein, by reference, in its
entirety.
* * * * *