U.S. patent application number 10/458302 was filed with the patent office on 2003-12-18 for image stabilization apparatus.
This patent application is currently assigned to Nikon Vision Co., Ltd.. Invention is credited to Haga, Shunichi, Yamamoto, Mitsuo, Yokoi, Youichi.
Application Number | 20030231393 10/458302 |
Document ID | / |
Family ID | 29727891 |
Filed Date | 2003-12-18 |
United States Patent
Application |
20030231393 |
Kind Code |
A1 |
Yamamoto, Mitsuo ; et
al. |
December 18, 2003 |
Image stabilization apparatus
Abstract
An image stabilization apparatus comprises a housing
accommodating an optical system in the interior thereof. A part of
optical members that compose the optical system is held to allow
angular displacement relative to the housing, and the position of
the part of the optical members is maintained in a predetermined
state. The part of the optical members is driven to restore the
position angularly displaced. A driving amount is controlled based
on information of the angular displacement. A mode for controlling
the housing that is suitable for vibration applied to the housing
is determined, and the mode is informed to a user.
Inventors: |
Yamamoto, Mitsuo;
(Yokohama-shi, JP) ; Yokoi, Youichi;
(Kasukabe-shi, JP) ; Haga, Shunichi; (Tokyo,
JP) |
Correspondence
Address: |
MILES & STOCKBRIDGE PC
1751 PINNACLE DRIVE
SUITE 500
MCLEAN
VA
22102-3833
US
|
Assignee: |
Nikon Vision Co., Ltd.
Nikon Corporation
|
Family ID: |
29727891 |
Appl. No.: |
10/458302 |
Filed: |
June 11, 2003 |
Current U.S.
Class: |
359/557 ;
359/407; 359/409; 359/554 |
Current CPC
Class: |
G02B 27/646
20130101 |
Class at
Publication: |
359/557 ;
359/407; 359/409; 359/554 |
International
Class: |
G02B 027/64 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 13, 2002 |
JP |
2002-173031 |
Claims
What is claimed is:
1. An image stabilization apparatus comprising: a housing
accommodating an optical system in the interior thereof; holding
means for holding a part of optical members that compose said
optical system in such a way as to allow angular displacement of
said part of the optical members relative to said housing, in order
to maintain the position of said part of the optical members in a
predetermined state; driving means for angularly displacing said
part of the optical members in the direction for restoring the
position of said part of the optical members that have been
angularly displaced by said holding member; control means for
controlling a driving amount of said driving means, said control
means including detection means for detecting information on
angular displacement of said part of the optical members caused by
said holding means and determination means for determining, based
on the information detected by said detection means, a mode for
controlling said housing that is suitable for vibration applied to
said housing; and an informing section that informs a user of said
control method determined by said determination means.
2. An image stabilization apparatus according to claim 1, wherein
said angular displacement information comprises information on
angular velocity of said holding means and/or information on
angular displacement amount of said holding means.
3. An image stabilization apparatus according to claim 1, wherein
the determination by said determination means is made based on a
comparison of a predetermined reference value and said angular
displacement information.
4. An image stabilization apparatus according to claim 3, wherein
said reference value comprises a reference value for the angular
velocity and/or a reference value for the angular displacement
amount.
5. An image stabilization apparatus according to claim 3, wherein
determination by said determination means is made based on a
comparison of said reference value and said angular displacement
information obtained within a predetermined sampling time, and
based on the number of times said angular displacement information
becomes larger than and/or smaller than said reference value.
6. An image stabilization apparatus according to claim 1, wherein
the control mode determined by said determination means is selected
for at least two vibration reduction modes.
7. An image stabilization apparatus according to claim 1, wherein
the apparatus is so adapted that the user can select an automatic
switching mode in which the control mode is automatically switched
to the mode determined by said determination means based on the
angular displacement information detected by said detection means
or a user setting mode in which the user is allowed to select the
control mode.
8. An image stabilization apparatus according to claim 1, wherein
said informing section provides information on the control mode
determined by said determination means.
9. An image stabilization apparatus according to claim 7, wherein
when the selected mode is said user setting mode, said informing
section provides information on whether the mode selected under
said user setting mode and the mode determined by said
determination means are different or identical.
10. An image stabilization apparatus according to claim 1, wherein
the apparatus is so adapted that the user can select and set any
mode based on the control mode of which the user is informed by
said informing section.
11. An image stabilization apparatus according to claim 10, further
comprising an observation optical system, wherein said informing
section includes a display section disposed within a view field of
said observation optical system; the apparatus is provided with a
mode selecting section for changing over the mode, the mode
selecting section including a button for selecting any one of said
modes and said display section displaying a mark which has a same
shape as that of said button.
12. An image stabilization apparatus according to claim 1 further
comprising first calculation means for performing calculation on a
detection result of said detection means based on a first
predetermined calculation method to determine said driving amount,
second calculation means for performing calculation on a detection
result of said detection means based on a second predetermined
calculation method to determine said driving amount, and decision
means for determining calculation means, from among said first and
second calculation means, that is suitable for vibration applied to
said housing.
13. An image stabilization apparatus according to claim 12, wherein
said decision means makes said determination by comparing the
detection result of said detection means with a predetermined
reference value.
14. An image stabilization apparatus according to claim 12 further
comprising an automatic mode switching means for causing said
driving means to operate by said driving amount determined by the
calculation means that is determined from among said first and
second calculation means by said decision means.
15. An image stabilization apparatus according to claim 12, wherein
when a displacement amount based on said information on angular
displacement deviates from a predetermined range a predetermined
number of times or more within a predetermined sampling time, said
decision means determines that panning or tilting of said housing
is occurring and selects calculation means that is suitable for the
panning or tilting from among said first and second calculation
means.
16. An image stabilization apparatus according to claim 12, wherein
when said angular velocity deviates from said predetermined range
said number of times or more than said number of times within said
predetermined sampling time, said decision means determines that
the user is on a conveyance so as to select calculation means that
is suitable for vibration caused by said conveyance from among said
first and second calculation means.
17. An image stabilizing apparatus according to claim 1 further
comprising an observation optical system, wherein said informing
section includes a display provided within a field of view of said
observation optical system.
18. An image stabilization apparatus according to claim 1, wherein
said informing section includes a sound generator with which said
informing section provides information using a sound.
19. A binocular comprising: a pair of eyepiece optical systems; a
pair of objective optical systems; an intermediate optical system
provided on an optical axis between said eyepiece optical systems
and objective optical systems; a housing accommodating said
eyepiece optical systems, said objective optical systems and said
intermediate optical system; holding means for holding a part of
optical members that compose said intermediate optical system in
such a way as to allow angular displacement of said part of the
optical members relative to said housing, in order to maintain the
position of said part of the optical members in a predetermined
state; driving means for angularly displacing said part of the
optical members in the direction for restoring the position of said
part of the optical members that have been angularly displaced by
said holding member; control means for controlling a driving amount
of said driving means, said control means including detection means
for detecting information on angular displacement of said part of
the optical members caused by said holding means and determination
means for determining, based on the information detected by said
detection means, a mode for controlling said housing that is
suitable for vibration applied to said housing; and an informing
section that informs a user of said control method determined by
said determination means.
Description
[0001] This application claims the benefit of Japanese Patent
application No. 2002-173031 which is hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an image stabilization
apparatus to be equipped in various optical apparatus such as a
binocular or monocular.
[0004] 2. Related Background Art
[0005] Reference is made here, by way of example, to Japanese
Patent Application Laid-Open No. 10-104681, which discloses an
image stabilization apparatus. A prior art image stabilization
apparatus disclosed in this Japanese Patent Application Laid-Open
No. 10-104681 is provided with an erecting prism, a gimbaled member
to which the erecting prism is attached, position feedback control
means and angular velocity feedback control means for controlling
the position or posture of the gimbaled member. The angular
velocity feedback control means is a feedback loop that detects an
angular velocity of the gimbaled member that is created due to hand
shake or other causes and enhances following-up ability of the
gimbaled member to the optical axis of the objective lens based on
a detection result. A position feedback loop is a feedback loop
that detects an angular displacement of the gimbaled member that is
created due to hand shake or other causes and enhances following-up
ability of the gimbaled member to the optical axis of the objective
lens based on a detection result. With the above-described
structure, Japanese Patent Application Laid-open No. 10-104681
teaches a technology to change a gain of the position feedback
control means in response to a user's switching operation of a mode
switch to realize a mode for reducing vibration created by hand
shake and a mode for providing a high following-up performance to
panning and tilting operations.
[0006] Another patent document Japanese Patent Application
Laid-Open No. 2001-100106 discloses an image stabilization
apparatus in which a vibration reduction mode and a panning/tilting
mode are switched automatically.
[0007] Specifically, in this prior art, the apparatus detects the
angular velocity and an angular displacement of a gimbaled member
and determines whether or not the detected values are larger (or
alternatively, smaller) than predetermined values. Then, the
apparatus determines an appropriate mode to automatically set this
appropriate mode.
[0008] In addition, in the technology disclosed in Japanese Patent
Application Laid-Open No. 2001-100106, a user can freely switch the
mode at his or her will by a manual operation. Even during
observation under a mode that has been set manually, the apparatus
detects the angular velocity and the angular positional
displacement of the gimbaled member, determines the appropriate
mode, and when it is determined that the appropriate mode is
different from the manually selected mode, the mode is
automatically switched to the appropriate mode determined by the
apparatus.
[0009] In the above-described technology disclosed in Japanese
Patent Application Laid-Open No. 10-104681, the mode is manually
selected on user's own discretion, and therefore it would be
difficult for an unskilled user to determine the optimum mode
definitely. Therefore, in some cases, a mode other than that
selected by the user may be the optimum mode. In such cases, the
performance of the apparatus would not brought out fully.
[0010] On the other hand, in the technology disclosed in Japanese
Patent Application Laid-Open No. 2001-100106, the switching of the
vibration reduction mode is effected automatically in accordance
with the degree of the vibration of the apparatus. However, if the
mode is thus switched automatically, the mode determined by the
apparatus as the appropriate mode sometimes differs from the mode
that the user has selected in accordance with his or her intention.
In that case, the user sometimes feels it undesirable to observe
under the mode automatically switched based on the determination by
the apparatus.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is to provide an image
stabilization apparatus that has a good usability.
[0012] In order to attain the above object, according to one aspect
of the present invention, there is provided an image stabilization
apparatus comprising:
[0013] a housing accommodating an optical system in the interior
thereof;
[0014] holding means for holding a part of optical members that
compose the optical system in such a way as to allow angular
displacement of said part of the optical members relative to the
housing, in order to maintain the position of said part of the
optical members in a predetermined state;
[0015] driving means for angularly displacing said part of the
optical members in the direction for restoring the position of said
part of the optical members that have been angularly displaced by
the holding member;
[0016] control means for controlling a driving amount of the
driving means, the control means including detection means for
detecting information on angular displacement of said part of the
optical members caused by the holding means and determination means
for determining, based on the information detected by the detection
means, a mode for controlling the housing that is suitable for
vibration applied to the housing; and
[0017] an informing section that informs a user of the control
method determined by the determination means.
[0018] In the image stabilization apparatus according to the
present invention, the angular displacement information may
comprise information on angular velocity of the holding means
and/or information on angular displacement amount of the holding
means.
[0019] In the image stabilization apparatus according to the
present invention, the determination by the determination means may
be made based on a comparison of a predetermined reference value
and the angular displacement information.
[0020] In the image stabilization apparatus according to the
present invention, the reference value may comprise a reference
value for the angular velocity and/or a reference value for the
angular displacement amount.
[0021] In the image stabilization apparatus according to the
present invention, the determination by the determination means may
be made based on a comparison of the reference value and the
angular displacement information obtained within a predetermined
sampling time, and based on the number of times the angular
displacement information becomes larger than and/or smaller than
the reference value.
[0022] In the image stabilization apparatus according to the
present invention, the control mode determined by the determination
means may be selected for at least two vibration reduction
modes.
[0023] In the image stabilization apparatus according to the
present invention, the apparatus may be so adapted that the user
can select an automatic switching mode in which the control mode is
automatically switched to the mode determined by the determination
means based on the angular displacement information detected by the
detection means or a user setting mode in which the user is allowed
to select the control mode.
[0024] In addition, in this image stabilization apparatus, when the
selected mode is the user setting mode, the informing section may
be adapted to provide information on whether the mode selected
under the user setting mode and the mode determined by the
determination means are different or identical.
[0025] In the image stabilization apparatus according to the
present invention, the informing section may be adapted to provide
information on the control mode determined by the determination
means.
[0026] In the image stabilization apparatus according to the
present invention, the apparatus may be so adapted that the user
can select and set any mode based on the control mode of which the
user is informed by the informing section.
[0027] The image stabilization apparatus according to the present
invention may further comprises first calculation means for
performing calculation on a detection result of the detection means
based on a first predetermined calculation method to determine the
driving amount, second calculation means for performing calculation
on a detection result of the detection means based on a second
predetermined calculation method to determine the driving amount,
and decision means for determining calculation means, from among
the first and second calculation means, that is suitable for
vibration applied to the housing.
[0028] In this image stabilization apparatus, the decision means
may make the determination by comparing the detection result of the
detection means with a predetermined reference value.
[0029] This image stabilization apparatus may further comprise an
automatic mode switching means for causing the driving means to
operate by the driving amount determined by the calculation means
that is determined from among the first and second calculation
means by the decision means.
[0030] In this image stabilization apparatus, when an angular
displacement amount based on the information on angular
displacement deviates from a predetermined range a predetermined
number of times or more within a predetermined sampling time, the
decision means may be adapted to determine that panning or tilting
of the housing is occurring and select calculation means that is
suitable for the panning or tilting from among the first and second
calculation means.
[0031] In this image stabilization apparatus, when the angular
velocity deviates from the predetermined range said number of times
or more than said number of times within the predetermined sampling
time, the decision means may be adapted to determine that the user
is on a conveyance so as to select calculation means that is
suitable for vibration caused by the conveyance from among the
first and second calculation means.
[0032] The image stabilizing apparatus according to the present
invention may further comprise an observation optical system, and
the informing section may include a display provided within a field
of view of the observation optical system.
[0033] In the image stabilization apparatus according to the
present invention, the informing section may include a sound
generator with which the informing section provides information
using a sound.
[0034] According to another aspect of the present invention, there
is provided a binocular comprising:
[0035] a pair of eyepiece optical systems;
[0036] a pair of objective optical systems;
[0037] an intermediate optical system provided on an optical axis
between the eyepiece optical systems and objective optical
systems;
[0038] a housing accommodating the eyepiece optical systems, the
objective optical systems and the intermediate optical system;
[0039] holding means for holding a part of optical members that
compose the intermediate optical system in such a way as to allow
angular displacement of said part of the optical members relative
to the housing, in order to maintain the position of said part of
the optical members in a predetermined state;
[0040] driving means for angularly displacing said part of the
optical members in the direction for restoring the position of said
part of the optical members that have been angularly displaced by
the holding member;
[0041] control means for controlling a driving amount of the
driving means, the control means including detection means for
detecting information on angular displacement of said part of the
optical members caused by the holding means and determination means
for determining, based on the information detected by the detection
means, a mode for controlling the housing that is suitable for
vibration applied to the housing; and
[0042] an informing section that informs a user of the control
method determined by the determination means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 is a drawing schematically showing the internal
structure of a binocular as an embodiment of the present
invention.
[0044] FIG. 2A is a front view showing the structure of an image
stabilization apparatus 100 in the embodiment of the present
invention.
[0045] FIG. 2B is a cross sectional view taken on line A-A in FIG.
2A.
[0046] FIG. 3 is a rear view of the binocular according to the
first embodiment of the present invention.
[0047] FIG. 4 is a top view of the binocular according to the first
embodiment of the present invention.
[0048] FIG. 5 is a front view of the binocular according to the
first embodiment of the present invention.
[0049] FIG. 6 is a block diagram showing the structure of the image
stabilization apparatus 100 in the binocular according to the first
embodiment of the present invention.
[0050] FIG. 7 is a top view showing the structure of a mode setting
dial 105 of the image stabilization apparatus 100 in the binocular
according to the first embodiment of the present invention.
[0051] FIG. 8 is a flow chart showing a control process performed
by a CPU 601 of the image stabilization apparatus 100 in the
binocular according to the first embodiment of the present
invention.
[0052] FIG. 9 is a top view showing the structure of a navigation
display changing switch 107 of the image stabilization apparatus
100 in the binocular according to the first embodiment of the
present invention.
[0053] FIG. 10 is a drawing illustrating a display 201 within the
field of view 200 of the binocular according to the first
embodiment of the present invention.
[0054] FIG. 11 is a top view of a binocular according to the second
embodiment of the present invention.
[0055] FIG. 12 is a drawing illustrating displays 202, 203 and 204
within the field of view 200 of the binocular according to the
second embodiment of the present invention.
[0056] FIGS. 13A and 13B are diagrams for illustrating comparison
of reference values and signals in a process for determining
vibration reduction mode performed by the CPU 601 of the image
stabilization apparatus 100 according to the first embodiment of
the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0057] In the following, embodiments of the present invention will
be described. In the following embodiments, descriptions will be
made with reference to an image stabilization apparatus equipped in
a binocular. However, it should be understood that the present
invention may also be applied to other optical apparatus. For
example, the invention may be applied to a monocular apparatus such
as a telescope etc.
[0058] First, a description will be made of a binocular equipped
with an image stabilization apparatus as a first embodiment of the
present invention.
[0059] Referring to FIG. 1 and FIG. 2A, The binocular equipped with
an image stabilization apparatus according to the embodiment has a
binocular optical system 10, a housing 1 accommodating the
binocular optical system, and an image stabilization apparatus 100.
The image stabilization apparatus 100 is adapted to detect
vibration generated during use of the binocular, such as vibration
applied to the housing 1 due to hand shake, and to suppress such
vibration.
[0060] As shown in FIG. 1, the binocular optical system 10 includes
an objective optical system 11, an eyepiece optical system 13, an
intermediate optical system 12 disposed between the objective
optical system 11 and the eyepiece optical system 13. As
illustrated in FIGS. 1 and 3, the objective optical system 11
includes objective lenses 11R and 11L. As shown in FIGS. 1, 4 and
5, the eyepiece optical system 13 includes an eyepiece barrels 101R
and 101L and eyepiece lenses 13R and 13L. The intermediate optical
system 12 functions to direct a light flux from the objective
optical system 11 to the eyepiece optical system 13. The
intermediate optical system 12 is provided for performing, when
vibration occurs in the binocular, optical compensation to prevent
an object from disappearing out of the field of view. In this
embodiment, the intermediate optical system 12 includes erecting
prisms 12R and 12L.
[0061] The image stabilization apparatus 100 has a gimbal mechanism
110. The gimbal mechanism 110 includes an outer gimbaled member 111
having a rotation axis parallel to X-axis and an inner gimbaled
member 112 having a rotation axis parallel to Y-axis. The inner
gimbaled member 112 is supported by rotation shaft 112a in such a
way as to be rotatable relative to the outer gimbaled member 111.
The outer gimbaled member 111 is supported by rotation shaft 111a
in such a way as to be rotatable relative to the housing 1. The
inner gimbaled member 112 holds the erecting prisms 12R and 12L
between two plate members 112b and 112c. The plate members 112b and
112c have openings 112d and 112e respectively at the positions of
the left and right optical paths. With the above-described
structure, when vibration or panning/tilting of the housing 1
occurs, the gimbaled members 111 and 112 are rotated relative to
the housing respectively by inertial force so that the direction of
the optical axes of the erecting prisms 12R and 12L would be kept
unchanged with respect to the inertial system (i.e. with respect to
the earth).
[0062] On the outer gimbaled member 111, there is mounted an
angular velocity detector 121 for detecting the angular velocity
.omega.x of the rotational movement about the rotation axis 111a
parallel to X-axis. On the inner gimbaled member 112, there is
mounted an angular velocity detector 122 for detecting the angular
velocity .omega.y of the rotational movement about the rotation
axis 112a parallel to X-axis. Each of the angular velocity
detectors 121 and 122 may be composed, for example, of a
piezoelectric vibration gyro sensor.
[0063] In addition, an angular displacement detector 141 for
detecting an angular displacement (i.e. a change in the angular
position) .theta.x caused by the rotation is attached to the
rotation shaft 111a for rotation about the axis parallel to X-axis.
Furthermore, an actuator 131 for rotationally driving the rotation
shaft 111a that has been rotationally displaced in the rotational
direction for returning back the rotation axis 111a is also
attached to the rotation shaft 111a. Similarly, to the rotation
axis 112a for rotation about the axis parallel to Y-axis, there is
attached an angular displacement detector 142 for detecting an
angular displacement .theta.y caused by the rotation and an
actuator 132 for rotationally driving the rotation shaft 112a that
has been rotationally displaced in the rotational direction for
returning back the rotation axis 112a. Thus, the angular
displacement of the rotation of the outer and inner gimbaled
members 111 and 112 about axes parallel to X-axis and Y-axis can be
detected based on outputs of the angular displacement detectors 141
and 142. The directions of rotational drive by the actuators 131
and 132 are such directions with which the optical axis of the
erecting prism 12R and 12L mounted on the gimbaled member 111 and
112 that have been rotated by inertial force would be restored to
the original position (i.e. the optical axis of the objective
optical system 11). Each of the actuators 131 and 132 may include,
for example, a servo mechanism. Each of the angular displacement
detectors 141 and 142 may include a rotary encoder.
[0064] As shown in FIG. 4, the image stabilization apparatus 100 is
further provided with a button 251 for turning on/off the vibration
reduction function disposed on the top surface of the housing 1, a
sound generator 254 and a battery box 108. In addition, as shown in
FIG. 5, the image stabilization apparatus 100 is provided with a
switch 107 for switching a navigation display disposed on the front
surface of the housing 1 and a mode setting dial 105. Furthermore,
referring to FIG. 6, the image stabilization apparatus 100 has a
CPU (central processing unit) 601, an amplifier section 602, an A/D
converter 603, a reference value storing section 604, a D/A
converter 605 and a calculator section 606. The control system as
described above is accommodated in the interior of the housing 1.
The image stabilization apparatus 100 is further provided with a
display within the field of view 201 disposed within the field of
view of either one of the eyepiece lenses 13R and 13L. In addition,
a display 109 and a focus knob 106 are also provided on the front
side surface of the housing 1.
[0065] The mode setting dial 105 is a dial type switch used for
selecting the vibration reduction mode of the image stabilization
apparatus 100. The apparatus according to this embodiment has two
vibration reduction modes (mode VR1 and mode VR2) and an automatic
mode for switching the mode VR1 and the mode VR2 automatically.
While the apparatus according to this embodiment is described to
have two modes VR1 and VR2 by way of example, the apparatus may be
adapted to have more than two modes to be switched. The mode VR1 is
a mode that is suitable for stabilizing the image at the occasion
of performing observation on a steady ground or observation which
involves frequent panning and tilting operations (e.g. at the time
of bird watching). On the other hand, the mode VR2 is a mode
suitable for stabilizing the image at the occasion of performing
observation on a swinging or wavering board of a conveyance (e.g. a
ship, a vehicle, an airplane or a helicopter etc.). The mode
setting dial 105 has five positions to be switched, that is,
"POWER-OFF" position 1051, "POWER-ON (VR AUTO: auto vibration
reduction)" position 1052, "VR1" position 1053, "VR2" position 1054
and "SHIFT" position 1055. When the mode setting dial 105 is set to
the "POWER-OFF" position 1051, power supply from the battery box
108 to each section of the image stabilization apparatus 100 is
turned off and disabled, so that the gimbal mechanism 110 is placed
into a locked state in which the gimbal mechanism 110 is maintained
at the position of the center of the optical axis without angular
displacement. Under this state, the binocular behaves as an
ordinary binocular that is not provided with a vibration reduction
function. When the mode setting dial 105 is set to the "POWER-ON
(VR AUTO)" position 1052, the image stabilization apparatus 100 is
turned on, and the vibration reduction mode is set to the automatic
switching mode. When the mode setting dial 105 is set to the "VR1"
position 1053 or the "VR2" position 1054, the vibration reduction
mode is set to the vibration reduction mode VR1 or VR2
respectively. The operation under the dial setting to the "SHIFT"
position 1055 will be described later.
[0066] In the following, functions characterizing the present
invention will be specifically described. As shown in FIG. 10, the
display within the field of view 201 is composed, for example, of
an LED or other elements, and it is disposed in the field of view
200 of either one of the eyepiece lenses 13R and 13L. Under the
state in which a vibration reduction mode is selected by setting of
the mode setting dial 105 to the "VR1" position 1053 or the "VR2"
position, if it is determined, based on the level or degree of the
external vibration actually applied to the housing 1, that the
selected mode is not the optimal mode, the display in the field of
view 201 indicates with red light. This prompts the user to change
the mode selected by the mode setting dial 105 to another mode.
Such a prompting function for changing the mode is referred to in
this embodiment as a vibration reduction mode navigation
function.
[0067] Referring to FIG. 9, a navigation display changing switch
107 has multiple positions to be switched, namely, a "NAVI-OFF"
position 901, an eye-mark position 902 and an ear-mark position
903. When the navigation display changing switch 107 is set to the
eye-mark position 902, the prompt for changing the vibration
reduction mode is performed by means of the display within the
field of view 201. On the other hand, when the navigation display
changing switch 107 is set to the ear-mark position 903, the
indication by the display within the field of view 201 is not
performed, but prompt for changing the vibration reduction mode is
performed by beep sound or voice sound for prompting mode change
generated by the sound generator 254. When the beep sound is used,
its sound duration time or its frequency may be modulated in
accordance with the vibration reduction mode. When the navigation
display changing switch is set to the "NAVI OFF" position 901, the
vibration reduction mode navigation function is disabled.
[0068] The vibration reduction on/off button 251 is enabled when
the mode setting dial 105 is set to either one of the "POWER-ON (VR
AUTO)" position 1052, the "VR1" position 1053, the "VR2" position
1054 or the "SHIFT" position 1055. When the mode setting dial 105
is set to either one of the "POWER-ON (VR AUTO)" position 1052, the
"VR1" position 1053 or the "VR2" position 1054, the state in which
the vibration reduction mode is disabled and the state in which the
vibration reduction mode is enabled are alternately switched by
manipulation of the vibration reduction on/off button. Under the
state in which the vibration reduction mode is disabled, the gimbal
mechanism 110 is placed in the locked state in which the gimbal
mechanism is positioned at the original position without angular
displacement. Under the state in which the vibration reduction mode
is enabled, the vibration reduction mode corresponding to the
setting of the mode setting dial 105 (i.e. either one of the auto
switching mode, the VR1 mode or the VR2 mode) is enabled.
Therefore, during observation under the vibration reduction mode
(i.e. either one of the auto switching mode, the VR1 mode or the
VR2 mode), the vibration reduction on/off button is useful for the
user, when the user wants to disable the vibration reduction mode
to lock the gimbal mechanism instantaneously for power saving or
other reasons.
[0069] On the other hand, when the mode setting dial 105 is set to
the "SHIFT" position 1055, the vibration reduction mode is
alternately switched between VR1 and VR2 by manipulation of the
vibration reduction on/off button 251. Therefore, during
observation under the mode VR2, the mode setting dial 105 may be
set to the "SHIFT" position in preparation for panning and tilting
operation for following up an object such as a bird or an airplane
that may possibly comes within the field of view, so that the
vibration reduction mode can be changed to the mode VR2 by
manipulating (or pressing) the vibration reduction of/off button
251. In connection with this, when the mode setting dial 105 is set
to the "SHIFT" position 1055, the automatic vibration reduction
mode change and the information by the display within the field of
view 201 will not be enabled.
[0070] The above-described navigation function is so adapted to
prompt the user to change the vibration reduction mode selected by
the mode setting dial 105 into another mode. However, it may be
modified to inform the user of the optimal mode determined by the
external vibration level actually applied to the housing 1. If the
function is so modified, the user can know the optimal mode
determined by the apparatus, and therefore the user can be aware of
the difference between the optimal mode and the mode selected by
the user. In addition, if the mode selected by the user is also
displayed together with the optimal mode determined by the
apparatus, the user can recognize the difference in the modes
easily.
[0071] Next, in the following, control operations by the CPU 601 of
the image stabilization apparatus will be described.
[0072] The CPU 601 reads a program stored in the reference value
storing section 604 upon turning-on of the power supply and
executes the program to operate in the manner described in the flow
chart presented in FIG. 8. First, in step 801, the CPU 601
receives, via the A/D converter 603, signals V.omega.x and
V.omega.y that have been obtained by amplifying angular velocity
.omega.x and .omega.y detected by the angular velocity detector 121
and 122 by a predetermined gain in the amplifier section 602. In
addition, the CPU 601 also receives via the A/D converter 603,
signals V.theta.x and V.theta.y that have been obtained by
amplifying angular displacement .theta.x and .theta.y detected by
the angular velocity detector 141 and 142 by a predetermined gain
by the amplifier section 602.
[0073] Next in step 802, the CPU 601 compares the received angular
velocity signals V.omega.x and V.omega.y with reference angular
velocity values .+-.Vc1 stored in the reference value storing
section 604 in advance respectively. In addition, the CPU 601
compares the received angular displacement signals V.theta.x and
V.theta.y with reference angular displacement values .+-.Vc2 stored
in the reference value storing section 604 in advance respectively.
Based on the above-mentioned comparison, the CPU 601 determines
whether the optimal mode is the mode VR1 or the mode VR2.
[0074] In the apparatus according to this embodiment, the angular
velocity signals V.omega.x and V.omega.y are used as information
for detecting vibration caused by conveyance. Specifically, as will
be seen from FIG. 13A, if at least one of the angular velocity
signals V.omega.x and V.omega.y becomes larger than .+-.Vc1 or
smaller than -Vc1, it is determined that the user is on a
conveyance and so the mode VR2 is appropriate. In addition, in
order not to mistakenly interpret angular velocity signals
V.omega.x and V.omega.y corresponding to an user's unintentional
action as those corresponding to vibration of a conveyance, a
sampling time Ts is set in the apparatus according to this
embodiment as shown in FIG. 13A. If the state in which at least one
of the angular velocity signals V.omega.x and V.omega.y becomes
larger than +Vc1 or smaller than -Vc1 occurs more than once during
the sampling time Ts, it is determined that the optimal mode is the
mode VR2.
[0075] On the other hand, the angular displacement signals
V.omega.x and V.omega.y are used as information for detecting
panning and tilting operations. Specifically, as will be seen from
FIG. 13B, if at least one of the angular displacement signals
V.omega.x and V.omega.y becomes larger than +Vc2 or smaller than
-Vc2, it is determined that the user is performing a panning or
tilting operation and so the mode VR1 is appropriate. As in the
case of the angular velocity signals, in order to prevent erroneous
interpretation of output corresponding to an user's unintentional
action, if the state in which at least one of the angular
displacement signals V.theta.x and V.theta.y becomes larger than
+Vc1 or smaller than -Vc2 occurs more than once during the sampling
time Ts, it is determined that the optimal mode is the mode
VR1.
[0076] In the case in which the determination of the optimal mode
conflicts between VR1 and VR2 (for example, when a user on a
conveyance is performing panning or tilting operation), in other
words, in the case in which at least one of V.omega.x and V.omega.y
becomes larger than +Vc1 or smaller than -Vc1 more than once within
the sampling time Ts and at least one of V.omega.x and V.omega.y
becomes larger than +Vc2 or smaller than -Vc2 more than once within
the sampling time Ts, it is determined in the apparatus according
to this embodiment that the mode VR1 for panning/tilting is the
optimal mode.
[0077] The above-described criteria in step 802 are summarized as
follows:
[0078] (1) When during the sampling time Ts, both V.omega.x and
V.omega.y are within the range larger than -Vc1 and smaller than
+Vc1 (or deviate from this range only once) and at least one of
V.theta.x and V.theta.y becomes smaller than -Vc2 or larger than
+Vc2 more than once, it is determined that the optimal mode is the
mode VR1;
[0079] (2) When during the sampling time Ts, both V.omega.x and
V.omega.y are within the range larger than -Vc1 and smaller than
+Vc1 (or deviate from this range only once) and both V.theta.x and
V.theta.y are within the range larger than -Vc2 and smaller than
+Vc2 (or deviate from this range only once), it is determined that
the optimal mode is the mode VR2;
[0080] (3) When during the sampling time Ts, at least one of
V.omega.x and V.omega.y becomes smaller than -Vc1 or larger than
+Vc1 more than once and at least one of V .theta.x and V.theta.y
becomes smaller than -Vc2 or larger than +Vc2 more than once, it is
determined that the optimal mode is the mode VR1; and
[0081] (4) When during the sampling time Ts, at least one of
V.omega.x and V.omega.y becomes smaller than -Vc1 or larger than
+Vc1 more than once and both V.omega.x and V.omega.y are within the
range larger than -Vc2 and smaller than +Vc2 (or deviate from this
range only once), it is determined that the optimal mode is the
mode VR2 As per the above, in step 802, it is possible to determine
the vibration reduction mode VR1 or VR2 that is optimal to the
vibration level applied to the binocular, by comparing the angular
velocity signals V.omega.x and V.omega.y and angular displacement
signals V.theta.x and V.theta.y with the reference values .+-.Vc1
and .+-.Vc2 respectively.
[0082] Next in step 803, the CPU 601 reads to which position 1052
to 1055 the mode setting dial 105 is set. When the mode setting
dial 105 is set to the "POWER-ON (VR AUTO)" position 1052, which
means that automatic switching of the vibration reduction mode is
selected, the process proceeds to step 804. In step 804, the CPU
601 controls to create outputs for causing the actuators 131 and
132 to rotationally drive the rotation shafts 111a and 111b of the
gimbal mechanism 110 in accordance with the optimal vibration mode
VR1 or VR2 determined in step 802.
[0083] Specifically, in step 804, if the vibration mode determined
in step 802 is the mode VR1, the CPU 601 controls to amplify the
angular velocity signals V.omega.x and V.omega.y at a predetermined
gain .alpha.1 and to amplify the angular displacement signals
V.theta.x and V.theta.y at a predetermined gain .beta.1 and to
output them. The output signals .alpha.1.times.V.omega.x,
.alpha.1.times.V.omega.y, .beta.1.times.V.theta.x and
.beta.1.times.V.theta.y are converted by the D/A converter 605 into
analog signals and then input to the calculation section 606. The
calculation section 606 performs predetermined calculation
processing such as addition or integration on the output
.alpha.1.times.V.omega.x and the output .beta.1.times.V.theta.x and
outputs the results to the actuator 131 for rotationally driving
the rotation shaft 111a about X-axis. Thus, the actuator 131
rotationally drives the rotation shaft 111a with a driving voltage
reflecting the outputs of the angular velocity signal V.omega.x and
the angular displacement signal V.theta.x so as to rotate the outer
gimbaled member 111 in the direction for bringing the optical axis
of the erecting prism 12R and 12L closer to the original position
(i.e. the optical axis of the objective optical system 11). In
addition, the calculation section 606 also performs calculation
processing such as addition or integration on the output
.alpha.1.times.V.omega.y and the output .beta.1.times.V.theta.y and
outputs the results to the actuator 132 for rotationally driving
the rotation shaft 112a about Y-axis. Thus, the actuator 132
rotationally drives the rotation shaft 112a with a driving voltage
reflecting the outputs of the angular velocity signal V.omega.y and
the angular displacement signal V.theta.y so as to rotate the inner
gimbaled member 112 in the direction for bringing the optical axis
of the erecting prism 12R and 12L closer to the original position
(i.e. the optical axis of the objective optical system 11).
[0084] On the other hand, in the case in which the vibration
reduction mode determined in step 802 is VR2, the CPU 601 also
controls in step 804 to amplify the angular velocity signals
V.omega.x and V.omega.y and the angular displacement signals
V.theta.x and V.theta.y so as to output them, but the amplification
is performed at gains .alpha.2 and .beta.2 respectively. While
gains .alpha.1 and .beta.1 are predetermined values for realizing
the vibration mode VR1 that is suitable for panning and tilting
operations, gains .alpha.2 and .beta.2 are predetermined values for
realizing the vibration reduction mode VR2 that is suitable for the
vibration of a conveyance. The gains .alpha.1 and .beta.1 in the
mode VR1 are set in such a way that the gimbal mechanism 110 is
restrained to the original position more strongly than in the mode
VR2. In other words, the gains .alpha.1 and .beta.1 for the mode
VR1 are so set that the field of view follows the movement of the
housing upon panning and tilting operations. On the other hand, the
gains .alpha.2 and .beta.2 in the mode VR2 are set in such a way
that the restraint of the gimbal mechanism 110 to the original
position is weaker than in the mode VR1. In other words, the gains
.alpha.2 and .beta.2 in the mode VR2 are so set that the field of
view is kept as constant (or steady) as possible relative to the
inertial system (i.e. relative to the earth) even if the binocular
vibrates due to vibration of a conveyance. Specifically, the ratio
of the gain .alpha.1 for the angular velocity signal to the gain
.beta.1 for the angular displacement signal in the mode VR1 is made
larger than the ratio of the gain .alpha.2 for the angular velocity
signal to the gain .beta.2 for the angular displacement signal in
the mode VR2.
[0085] As per the above, the automatic switching of the vibration
reduction mode between VR1 and VR2 is realized in step 804.
[0086] On the other hand, when it is turned out in step 803 that
the mode setting dial 105 is set to the "VR1" position 1053 or the
"VR2" position 1054, the process proceeds to step 805. In step 805,
it is further determined whether the mode setting dial 105 is in
the "VR1" position 1053 or in the "VR2" position 1054. When it is
determined that the mode setting dial 105 is in the "VR1" position
1053, the process proceeds to step 806. In step 806, it is
determined whether or not the optimal vibration reduction mode
determined in step 802 is identical to the mode VR1 set by the mode
setting dial 105. If they are not identical, the process proceeds
to step 807, in which information for prompting mode change is
presented to the user, since the currently set vibration reduction
mode is not appropriate. The way of informing the user is pursuant
to the setting by the navigation information changing switch 107.
Specifically, when the eye-mark position 902 is selected, the LED
in the display within the field of view 201 is turned on in red,
while when the ear-mark position 903 is selected, a beep sound or a
voice sound is generated from the sound generator 254, and then the
process proceeds to step 808. In connection with this, when the
navigation information changing switch 107 is set to the "NAVI OFF"
position 901, the information is not presented and the process
proceeds to step 808.
[0087] In the process shown in the flow chart of FIG. 8, it is
determined in step 806 whether or not the optimal vibration
reduction mode determined in step 802 is identical to the mode set
by the user, which is determined in step 805. However, as described
before, in the present invention the process may be modified in
such a way as to inform the user of the optimal vibration reduction
mode determined in step 802. In that case, step 806 for determining
whether or not the optimal vibration reduction mode determined in
step 802 is identical to the mode set by the user is not necessary
(i.e. can be omitted). Therefore, the information made in step 807
will be information on the optimal vibration reduction mode
determined in step 802.
[0088] In step 808, in order to realize the mode VR1, the CPU 601
controls to amplify the angular velocity signals V.omega.x and
V.omega.y at a predetermined gain .alpha.1 and to amplify the
angular displacement signals V.theta.x and V.theta.y at a
predetermined gain .beta.1 and to output them in like manner as in
step 804. Thus, the actuators 131 and 132 rotationally drive the
rotation shafts 111a and 112a respectively with driving voltages
reflecting the outputs of the angular velocity signals and the
angular displacement signals so as to realize the vibration
reduction mode VR1.
[0089] In step 808, the vibration reduction mode is switched to the
optimal vibration reduction mode determined in step 802
automatically. However, in the present invention, whether or not
the mode suggested by the information in step 807 is to be selected
may be left to user's discretion. In that case, step 808 is not
necessary (i.e. can be omitted). Therefore, if the user considers
that observation under the mode selected by himself or herself is
satisfactory, the user can continue the observation while
maintaining the current mode without following the information. In
addition, even if the user considers that observation under the
current mode selected by himself or herself is satisfactory, the
user can change the mode once when a mode different from the
currently selected mode is suggested by the information and if the
suggested mode provides better observation, the user would observe
with the suggested mode. If the user finds, after changing the mode
to the suggested mode, that observation under the mode selected by
himself or herself is more preferable for him or her than
observation under the suggested mode, the user would change the
mode from the suggested mode to the mode previously selected by the
user again.
[0090] As per the above, the present invention can provide an
apparatus that reflects user's intention or taste to a greater
degree.
[0091] After the above-described steps, the process proceeds to
step 812, in which the CPU 601 detects whether or not the vibration
reduction on/off button 251 has been manipulated within a
predetermined time. When it is detected that the vibration
reduction of/off button has been manipulated, the process proceeds
to step 813, in which the CPU 601 outputs a signal for commanding
the actuators 131 and 132 to return the rotation shafts 111a and
112a to the original positions and to maintain (or lock) them at
that state. That signal is sent to the actuators 131 and 132 via
the D/A converter 605, the calculation section 606, and the
actuators 131 and 132 return the rotation shafts 111a and 112a to
their original positions to maintain (or lock) them in that state.
Thus, the gimbal mechanism 110 of the image stabilization apparatus
100 will not rotate from the original position, and therefore the
binocular behaves as an ordinary binocular that does not have a
vibration reduction function. The locking of the rotation shafts
111a and 112a is maintained until it is detected that the vibration
reduction on/off button 251 is manipulated (or pressed) again. If
it is determined in step 814 that the vibration reduction on/off
button 251 is pressed again and the locking is released, or if it
is determined in step 812 that the vibration reduction on/off
button 251 has not been manipulated, the process returns to step
801.
[0092] Referring back to step 805, if it is determined in step 805
that the mode setting dial 105 is in the "VR2" position 1054, the
process proceeds to step 809. In step 809, it is determined whether
or not the optimal vibration reduction mode determined in step 802
is identical to the mode VR2 set by the mode setting dial 105. If
they are not identical, the process proceeds to step 810, in which
information for prompting mode change is presented to the user in
like manner as in step 807, since the currently set vibration
reduction mode is not appropriate.
[0093] As described before, the process may be modified in such a
way as to inform the user of the optimal vibration reduction mode
that is determined in step 802. In that case, step 809 for
determining whether or not the optimal vibration reduction mode
determined in step 802 is identical to the mode set by the user
determined in step 805 is not necessary (i.e. can be omitted).
Therefore, step 809 and step 810 are not necessary, and information
of the optimal vibration reduction mode determined in step 802 is
made only in step 807.
[0094] Then the process proceeds to step 811. In step 811, in order
to realize the mode VR2, the CPU 601 controls to amplify the
angular velocity signals V.omega.x and V.omega.y at a predetermined
gain .alpha.2 and to amplify the angular displacement signals
V.theta.x and V.theta.y at a predetermined gain .beta.2 and to
output them in like manner as in step 804. Thus, the actuators 131
and 132 rotationally drive the rotation shafts 111a and 112a
respectively with driving voltages reflecting the outputs of the
angular velocity signals and the angular displacement signals so as
to realize the vibration reduction mode VR2. After that, the
process proceeds to step 812.
[0095] As described before, whether or not the mode suggested by
the information in step 810 is to be selected may be left to user's
discretion. In that case, step 810 is not necessary (i.e. can be
omitted).
[0096] Referring back to step 803, if the mode setting dial 105 is
set to the "SHIFT" position 1055, the process proceeds to step 815.
In step 815, it is determined whether the vibration reduction
on/off button 251 has been manipulated (or pressed) within a
predetermined time. In the state in which the mode setting dial 105
is set to the "SHIFT" position, the vibration reduction mode is
switched between VR1 and VR2 automatically. Therefore, if it is
determined in step 815 that the vibration reduction on/off button
251 has not been pressed, the process proceeds to step 816, and in
order to realize the vibration reduction mode same as the
previously set mode, which is assumed here to be the mode VR1 for
example, if the mode set in the latest step 816 is VR1, the CPU 601
controls to amplify the angular velocity signals V.omega.x and
V.omega.y at a predetermined gain .alpha.1 and to amplify the
angular displacement signals V.theta.x and V.theta.y at a
predetermined, gain .beta.1 and to output them. On the other hand,
if it is determined in step 815 that the vibration reduction on/off
button 251 has been pressed, the process proceeds to step 816, and
in order to realize the vibration reduction mode different from the
previously set mode (i.e. in order to realize the mode VR2, if the
mode set in the latest step 816 is VR1,), the CPU 601 controls to
amplify the angular velocity signals V.omega.x and V.omega.y at a
predetermined gain .alpha.2 and to amplify the angular displacement
signals V.theta.x and V.theta.y at a predetermined gain .beta.2 and
to output them. Thus, the actuators 131 and 132 rotationally drive
the rotation shafts 111a and 112a so as to realize vibration
reduction mode VR1 or VR2.
[0097] As per the above, in the binocular having the image
stabilization apparatus 100 according to this embodiment, it is
possible to realize a mode with which vibration reduction mode is
automatically switched in accordance with the level or degree of
vibration of the binocular. Under this automatic mode, it is
possible, by setting a sampling time Ts, to distinguish movement of
the binocular caused unintentionally by the user from intentional
panning/tilting operations or vibration caused by conveyance. In
addition, even if there is a time lag between detection of the
angular velocity of the gimbal mechanism and detection of the
angular displacement of the gimbal mechanism, it is possible to
determine the optimal vibration reduction mode.
[0098] In addition, when a vibration reduction mode is set by a
user at his or her will, the apparatus can inform the user whether
that mode is the optimal vibration reduction mode or not, based on
the above-described determination of the optimal vibration
reduction mode, to prompt the user to change the vibration
reduction mode to the optimal mode. In this way, the user can
notice whether or not the vibration reduction mode selected by him
or her is appropriate, and even inexperienced user can
appropriately select the mode. Therefore, it is possible to bring
out the performance of the image stabilization apparatus fully.
[0099] In the apparatus according to the above-described
embodiment, the optimal vibration reduction mode is determined
based on whether the angular velocity signal or the angular
displacement signal deviates from a reference range more than once
within the sampling time Ts. However, the frequency criterion is
not limited to "more than once", but it may also be "more than
twice" or other desirable frequency.
[0100] In steps 804, 808, 811 and 816 in FIG. 8, the gains are
varied in accordance with the vibration reduction mode in order to
realize modes VR1 and Vr2. But the apparatus may be modified in
such a way that the modes VR1 and VR2 are realized not only by
varying the gains but by performing calculation or other processing
that is predetermined for each mode.
[0101] Next, as a second embodiment, an apparatus in which a
modification is made to the displayed mark that appears, in
accordance with the informing process of steps 807 and 810, in the
display 201 within the field of view 200 in the apparatus according
to the first embodiment is modified.
[0102] In the second embodiment, as shown in FIG. 12, a display
within the field of view 200 includes a display 203 indicating an
upward red triangle mark, a display 204 indicating a downward red
triangle mark and a display 202 disposed between these displays
indicating a green circular mark. These displays can be realized by
LEDs or other devices. On the upper surface of a housing 1 of the
binocular, as shown in FIG. 11, there is provided vibration
reduction mode changing buttons 104a and 104b having the shapes
corresponding to the shapes of the marks of the displays 203 and
204. The button 104a is to be operated upon changing the vibration
reduction mode to mode VR2 when the currently set mode is mode VR1,
while the button 104b is to be operated upon changing the vibration
reduction mode to mode VR1 when the currently set mode is mode
VR2.
[0103] When in step 807 (in the process shown in the flow chart of
FIG. 8) the currently set mode VR1 is not the optimal mode, the CPU
601 causes the upward triangle mark of the display within the field
of view 203 to be turned on in red. If the user presses the
changing button 104a of the same shape in response to the turned-on
mark, the CPU 601 causes the circular mark of the display within
the field of view 202 to be turned on in green, and the process
proceeds to step 811, in which the process for the vibration
reduction mode VR2 (that is the mode set after the mode change) is
performed. On the other hand, if the user does not press the
changing button 104a of the same shape in step 807, the process
proceeds to step 808, in which the process for the vibration
reduction mode VR1 is continued without a mode change. Similarly,
when in step 810 the currently set mode VR2 is not the optimal
mode, the CPU 601 causes the downward triangle mark of the display
within the field of view 204 to be turned on in red. If the user
presses the changing button 104b of the same shape in response to
the turned-on mark, the CPU 601 causes the circular mark of the
display within the field of view 202 to be turned on in green, and
the process proceeds to step 808, in which the process for the
vibration reduction mode VR1 (that is the mode set after the mode
change) is performed. On the other hand, if the user does not press
the changing button 104b of the same shape in step 810, the process
proceeds to step 811, in which the process for the vibration
reduction mode VR2 is continued without a mode change.
[0104] The binocular provided with the image stabilization
apparatus according to the second embodiment having the
above-described structure realizes an advantageous effect that the
user can change the vibration reduction mode to select the optimal
mode by operating the button 104a or 104b by a finger in accordance
with a figure indicated in the display within the field of view
during observation without detaching the eyes from the eyepiece
lenses 13R and 13L.
[0105] In the process of providing information on the optimal mode
determined in step 802, the information may be provided by visual
displays or sounds specific to the respective modes that are
different from each other. It is preferable that the mode selected
by user be indicated in the field of view to inform the user of the
mode. When both the mode selected by the user and the optimal mode
determined in step 802 are displayed, the user can conveniently
recognize the difference between those modes at sight.
[0106] The displays within the field of view 203 and 204 may be
composed of LEDs or other elements that can emit a color light
selected from more than two color lights. In that case, the
comparison of the angular velocity signal and the angular
displacement signal with the reference ranges may be arranged in
such a way that the degrees of deviations of those signals from the
respective reference ranges are classified into two or more levels.
Thus, in the process of informing the user in steps 807 and 810,
those levels (or degrees) of the deviation are represented by
corresponding colors of light. For example, when the degree of the
deviation is relatively low, the displays within the field of view
203 and 204 are caused to emit yellow light, while when the degree
of the deviation is relatively high, the displays 203 and 204 are
caused to emit red light. Thus, the user can make a decision on the
vibration reduction mode in a customized way in accordance with his
or her intention, for example, in such a way as to change the
vibration reduction mode only when the degree of the deviation is
high. Therefore, it is possible to enlarge the variety of use for
user of the binocular.
[0107] The apparatus according to the above-described embodiment
has two vibration reduction modes (VR1, VR2), but the present
invention is also applicable to more than two vibration reduction
modes (VR1, VR2, VR3, . . . , VRn).
[0108] The apparatus according to the above-described embodiment is
provided with a gimbaled member on which prisms are mounted,
angular velocity feedback control means and position feedback
control means for controlling the position of the gimbaled member.
However, the present invention is also applicable to other types of
optical elements.
[0109] For example, the present invention can be applied to an
apparatus that uses a variable-angle prism for vibration reduction,
which is composed of two glass plates and liquid having a high
refractive index included between the glass plates in a sealed
manner. (The variable-angle prism itself has been already known,
and described for example in Japanese Patent Application Laid-Open
Nos. 10-319325 and 2000-10143.) In that case, the present invention
can be applied to an apparatus that has a variable-angle prism
position detector that detects an inclination angle of one of the
glass plates and a driving device such as a motor for driving that
glass plate in a direction for correcting an inclination of the
optical system based on the detection result.
[0110] The present invention can be applied to various apparatus in
which an inclination of the optical axis of an observation optical
system having an erecting prism or other element is detected and
the inclination is corrected based on a detection result.
[0111] The apparatus according to the present invention may be
provided with a mode selecting switch with which a user can select
automatic mode switching and manual mode switching that allows the
user to select desired mode. In this case, the user can select a
desired mode at his or her will depending on circumstances and the
user's operation skill.
[0112] As per the above, the present invention can provide an image
stabilization apparatus having a good usability.
* * * * *