U.S. patent application number 08/547201 was filed with the patent office on 2001-11-22 for image input apparatus having interchangeable image pickup device and pan head.
Invention is credited to KAWANO, KENJI.
Application Number | 20010043271 08/547201 |
Document ID | / |
Family ID | 17896042 |
Filed Date | 2001-11-22 |
United States Patent
Application |
20010043271 |
Kind Code |
A1 |
KAWANO, KENJI |
November 22, 2001 |
IMAGE INPUT APPARATUS HAVING INTERCHANGEABLE IMAGE PICKUP DEVICE
AND PAN HEAD
Abstract
An image input apparatus has a pan head for mounting an image
pickup device thereon and for changing the image pickup direction
of the image pickup device. The image pickup device has an engaging
device, and control terminals capable of transmitting specification
information about an operation of the pan head from the image
pickup device to the pan head. The pan head has a holding device to
be engaged with the engaging device so as to interchangeably hold
the image pickup device, identifying terminals capable of receiving
the specification information when the image pickup device is held
by the holding device, and a selection circuit for selecting an
operation of the pan head corresponding to the held image pickup
device based on the received specification information.
Inventors: |
KAWANO, KENJI; (TOKYO,
JP) |
Correspondence
Address: |
FITZPATRICK CELLA HARPER & SCINTO
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Family ID: |
17896042 |
Appl. No.: |
08/547201 |
Filed: |
October 24, 1995 |
Current U.S.
Class: |
348/211.99 ;
348/14.05; 348/373; 348/E5.044; 348/E7.079 |
Current CPC
Class: |
H04N 7/142 20130101;
H04N 5/23209 20130101 |
Class at
Publication: |
348/211 ;
348/373; 348/14.05 |
International
Class: |
H04N 005/232; H04N
007/14 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 10, 1994 |
JP |
301369/1994 |
Claims
What is claimed is:
1. A pan head for mounting an image pickup device thereon and for
changing the image pickup direction of the image pickup device,
said pan head comprising: (a) holding means for interchangeably
holding the image pickup device; and (b) selection means for
selecting a pan head operation corresponding to the image pickup
device held by said holding means when the image pickup device is
mounted on said holding means.
2. A pan head according to claim 1, further comprising receiving
means for receiving specification information used to specify the
pan head operation, the specification information corresponding to
the image pickup device mounted on said holding means.
3. A pan head according to claim 2, wherein said selection means
generates information used to select the pan head operation based
on the specification information received by said receiving
means.
4. A pan head according to claim 3, further comprising drive means
for executing the pan head operation based on the selection of said
selection means.
5. A pan head according to claim 4, further comprising a memory for
storing data on operations of said pan head corresponding to
different image pickup devices.
6. A pan head according to claim 5, wherein said drive means reads
out data on the pan head operation from said memory based on the
selection of said selection means when the image pickup device is
mounted on said holding means.
7. A pan head according to claim 6, wherein the data on the
operation of said pan head comprises data representing at least
either the driving voltage or the driving speed of said drive
means.
8. A pan head according to claim 3, wherein the image pickup device
has a plurality of control terminals for providing the
specification information, and wherein said receiving means has a
plurality of identifying terminals corresponding to the plurality
of control terminals of the image pickup device.
9. A pan head according to claim 8, wherein said selection means
(i) judges a connection state between the control terminals and
said identifying terminals when the image pickup device is mounted
on said holding means, and (ii) generates the selection information
based on the judgment result.
10. A pan head according to claim 2, wherein the image pickup
device has a lens mounted thereon, and wherein the specification
information for specifying the operation of said pan head comprises
information representing at least either the weight or the focal
length of the lens mounted on the image pickup device.
11. A pan head according to claim 1, wherein the image pickup
device has an input/output terminal for providing a control signal
relating to control of the image pickup device, and further
comprising a pan head input/output terminal to be connected to the
input/output terminal of the image pickup device for receiving the
signal relating to control of the image pickup device when the
image pickup device is mounted on said holding means.
12. An image pickup device mountable on a pan head which is capable
of changing an image pickup direction of said image pickup device,
the pan head having a holding means, said image pickup device
comprising: (a) engaging means engageable with the holding means of
the pan head; and (b) transmission means for transmitting to the
pan head information about an operation of the pan head with said
image pickup device.
13. An image pickup device according to claim 12, wherein said
transmission means has a control terminal for specifying an
operation of the pan head.
14. An image pickup device according to claim 12, wherein the pan
head has an input/output terminal, and further comprising an image
pickup device input/output terminal to be connected to the
input/output terminal of the pan head, for transmitting to the pan
head input/output terminal a signal relating to the control of said
image pickup device when said image pickup device is mounted on the
holding means.
15. An image input apparatus having a pan head for mounting an
image pickup device thereon and for changing the image pickup
direction of said image pickup device, said image input apparatus
comprising: (a) said image pickup device comprising: engaging
means; and transmission means for transmitting to said pan head
specification information which specifies an operation of said pan
head with said image pickup device, (b) said pan head comprising:
holding means engageable with said engaging means to
interchangeably connect said image pickup device and said pan head;
receiving means for receiving from said transmission means the
specification information when said image pickup device is
connected to said holding means; and selection means for selecting
an operation of said pan head corresponding to the connected image
pickup device based on the received specification information.
16. An image input apparatus according to claim 15, wherein said
selection means provides selection information for selecting the
operation of said pan head based on the specification information
received by said receiving means.
17. An image input apparatus according to claim 16, further
comprising pan head drive means for executing the operation of said
pan head based on the selection information of said selection
means.
18. An image input apparatus according to claim 17, further
comprising a pan head memory for storing data on operations of said
pan head corresponding to different image pickup devices.
19. An image input apparatus according to claim 18, wherein said
drive means (i) reads out from said memory data on the operation of
said pan head based on the selection information when said image
pickup device is mounted on said holding means, and (ii) executes
the operation of said pan head based on the read data.
20. An image input apparatus according to claim 19, wherein the
data on the operation of said pan head comprises data representing
at least either the driving voltage or the driving speed of said
drive means.
21. An image input apparatus according to claim 15, wherein said
image pickup device includes a lens mounted thereon, and wherein
the specification information for specifying the operation of said
pan head comprises information representing at least either the
weight or the focal length of a lens mounted on said image pickup
device.
22. An image input apparatus according to claim 15, wherein said
transmission means has a plurality of control terminals for
transmitting the specification information, and wherein said
receiving means has a plurality of identifying terminals
corresponding to said plurality of control terminals.
23. An image input apparatus according to claim 22, wherein said
selection means (i) determines a connection state between said
control terminals and said identifying terminals when said image
pickup device is mounted on said holding means, and (ii) generates
the selection information based on the judgment result.
24. An image input apparatus according to claim 15, further
comprising connecting means for transmitting from said pan head to
said image pickup deice a signal for the control of said image
pickup device when said image pickup device is mounted on said
holding means.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention The present invention relates to a
pan head for turning a pedestal (which has a mechanism for holding
an image pickup device) in at least one of the horizontal and
vertical directions. The present invention also relates to an image
pickup device held by such a pan head, and to an image input
apparatus provided with both the pan head and the image pickup
device.
[0002] 2. Description of the Related Art
[0003] In recent years, a video camera which generates video
signals corresponding to a subject has been widely used as an image
input apparatus for a computer, and a combination system made up of
this video camera and a computer (for example, a personal computer
and a work station) is proceeding toward practical utilization in
electronic mail for images, a videoconference system, and the
like.
[0004] In these electronic image mail and video conference systems,
a monitoring camera developed for monitoring, an image input
apparatus equipped with a combination of a monitoring camera with a
remote controlled lens and a remote controlled pan head for holding
the monitoring camera, and the like are used.
[0005] For example, in a videoconference system using only a
monitoring camera, the monitoring camera is fixed on the ceiling,
the wall or the like so as to capture a predetermined image taking
area. However, since the image taking area of the monitoring camera
is thus predetermined, it is impossible to adapt to various
circumstances, for example, to concentrate image taking on an
arbitrary speaker, by changing the image taking area during a
videoconference, which thus results in a failure to sufficiently
deliver functionality with respect to the videoconference.
[0006] On the other hand, in a videoconference system using an
image input apparatus equipped with a combination of a monitoring
camera with a remote controlled lens and a remote controlled pan
head for holding the monitoring camera, the pan head with the
monitoring camera mounted thereon is fixed on the ceiling, the wall
or the like, and the lens and the pan head are driven by remote
control as occasion demands. Since this method can change the image
taking area and direction by remote control, it is possible to
readily concentrate image taking on an arbitrary speaker, or to
take an image of the whole or part of a conference room, and
therefore, to sufficiently deliver functionality required for the
videoconference. Furthermore, a camera with a lens having an
appropriate focal length can be mounted on the pan head, which
allows the choice of a video camera with reference to the
environment such as a conference room.
[0007] The above-mentioned image input apparatus is equipped with a
pan head for interchangeably mounting a video camera thereon to
choose a video camera suited to the environment. However, since the
driving force of a pedestal in the pan head is set such as to cope
with the heaviest video camera to be mounted thereon, a large pan
head, which is high in cost, is needed. Therefore, it is difficult
to obtain a low-cost image input apparatus.
[0008] Furthermore, it is necessary to change the control on the
pan head in accordance with a video camera at every replacement of
the video camera, and this change is troublesome.
[0009] In order to lower the cost of the pan head and to simplify
the change of control on the pan head, a videoconference camera
combining an image pickup device and a pan head has been developed
and is nearing practical use. However, since the image pickup
device and the pan head are combined in the videoconference camera,
it is impossible to choose the camera with reference to the
environment, such as a conference room.
SUMMARY OF THE INVENTION
[0010] An object of the present invention is to provide an image
input apparatus which solves the above problems, achieves high
general versatility, reduces cost, and simplifies the change of
operation control on a pan head.
[0011] In order to achieve the above object, according to an aspect
of the present invention, there is provided an image input
apparatus having a pan head for mounting an image pickup device
thereon and for changing the image pickup direction (or
orientation) of said image pickup device, wherein the image pickup
device comprises an engaging portion and a transmission means
capable of transmitting specification information about an
operation of the pan head from the image pickup device to the pan
head, and the pan head comprises a holding portion to be engaged
with the engaging portion so as to interchangeably hold the image
pickup device, a receiving means capable of receiving the
specification information when the image pickup device is held by
the holding portion, and a selection means for selecting an
operation of the pan head corresponding to the held image pickup
device based on the specification information received.
[0012] According to another aspect of the present invention, there
is provided a pan head for mounting an image pickup device thereon
and for changing the image pickup direction of the image pickup
device, the pan head comprising a holding means for interchangeably
holding the image pickup device, and a selection means for
selecting an operation of the pan head corresponding to the image
pickup device when the image pickup device is mounted on the
holding means.
[0013] According to a further aspect of the present invention,
there is provided an image pickup device mountable on a pan head
capable of changing the image pickup direction of the image pickup
device, the image pickup device comprising an engaging portion to
be engaged with a holding portion provided in the pan head, and a
transmission means capable of transmitting information about an
operation of the pan head from the image pickup device to the pan
head.
[0014] These and other objects, features and advantages of the
present invention will become more apparent from the following
description of the preferred embodiment taken in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a block diagram showing the configuration of an
embodiment of an image input apparatus according to the present
invention;
[0016] FIG. 2 is a perspective view showing an outward appearance
of the image input apparatus shown in FIG. 1;
[0017] FIG. 3 is a perspective view showing a state in which a
camera head unit and a pan head unit of the image input apparatus
shown in FIG. 1 are separate;
[0018] FIG. 4 is a perspective view showing a control terminal and
an input/output terminal provided in the camera head unit of the
image input apparatus shown in FIG. 1;
[0019] FIG. 5 is a perspective view showing a terminal and an
input/output terminal of a pan head control switching mechanism
provided in the pan head unit of the image input apparatus shown in
FIG. 1;
[0020] FIG. 6 is a view showing a connecting state of operating
portions of the control terminal of the camera head unit and the
terminals of the pan head unit control switching mechanism;
[0021] FIG. 7 is a view showing a state before the operating
portions of the control terminal of the camera head unit and the
terminals of the pan head unit control switching mechanism are
connected;
[0022] FIG. 8 is a perspective view showing the structure of a
horizontal driver in the image input apparatus shown in FIG. 1;
[0023] FIG. 9 is a perspective view showing the structure of a
vertical driver in the image input apparatus shown in FIG. 1;
[0024] FIG. 10 is a view showing patterns of pan head switching
control modes in the image input apparatus shown in FIG. 1;
[0025] FIG. 11 is a graph showing the relation between the driving
speed and the driving voltage of the pan head when the weight of a
lens is used as a parameter;
[0026] FIG. 12 is a graph showing the relation between the pan head
driving speed and the lens focal length when the focal length is
used as a parameter;
[0027] FIG. 13 is a flowchart showing a pan head control switching
operation in the image input apparatus shown in FIG. 1;
[0028] FIG. 14 is a flowchart showing an optical axis control
operation in the image input apparatus shown in FIG. 1; and
[0029] FIG. 15 is a flowchart showing an initialization process of
the optical axis control operation in the image input apparatus
shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] A preferred embodiment of the present invention will now be
described in conjunction with the accompanying drawings.
[0031] The image input apparatus shown in FIGS. 1 to 3 is composed
of a camera head unit 21 and a pan head unit 22 which comprises an
electric pan head for mounting the camera head unit 21 thereon.
[0032] As shown in FIG. 1, the camera head unit 21 comprises a zoom
lens 1, an iris 2, an image pickup device 3, a signal processing
circuit 4, a camera controller 5, an iris driver 6, a focus
controller 7, and a zoom controller 8. The camera controller 5 is
capable of mutual communication with the devices and the circuits
within the camera head unit 21.
[0033] The image pickup device 3 is, for example, a CCD
(charge-coupled device) for converting an optical image obtained
through the zoom lens 1 into electric signals.
[0034] The signal processing circuit 4 generates video signals by
subjecting the electric signals from the image pickup device 3 to
predetermined processing, and outputs the video signals to an
external monitor (not shown) and a video recording/reproducing
apparatus (also not shown) through a terminal Vout. Parameters
related to the processing performed on the electric signals from
the image pickup device 3 by the signal processing circuit 4 are
controlled by the camera controller 5.
[0035] The iris driver 6 drives the iris 2 so that the amount of
light passing from the zoom lens 1 to the image pickup device 3 is
a predetermined amount, that is, the electric signals from the
image pickup device 3 are at a substantially constant level. The
drive amount of the iris 2 is designated by the camera controller
5.
[0036] The focus controller 7 drives some of the lenses
constituting the zoom leans 1 so that the zoom lens 1 is focused on
a predetermined subject. The drive amount is designated by the
camera controller 5.
[0037] The zoom controller 8 drives some of the lenses constituting
the zoom lens 1 to obtain a predetermined focal length of the zoom
lens 1. The drive amount is designated by the camera controller
5.
[0038] The camera controller 5 comprises a memory (not shown) and a
CPU (also not shown). The CPU determines the drive amounts of the
iris driver 6, the focus controller 7, and the zoom controller 8
based on information from an I/F controller 16, which will be
described later, and controls the processing operation of the
signal processing circuit 4. The memory stores data on the focal
length and weight of the zoom lens 1 and the like.
[0039] The camera controller 5 is provided with an input/output
terminal 10 for connecting the camera controller 5 to an external
device (for example, a personal computer, a work station and a
codec in a videoconference system) through the I/F controller 16 to
allow communication therebetween. The control terminal 9 for
connecting the camera controller 5 to a pan head control switching
mechanism 11 of the pan head unit 22 which will be described later.
The control terminal 9 is provided with three operating portions
9a, 9b and 9c for setting a pan head operation with respect to the
camera head unit 21.
[0040] The control terminal 9 and the input/output terminal 10 are,
as shown in FIG. 4, formed in a support member 31 attached to the
rear of a housing 21a of the camera head unit 21. The operating
portions 9a, 9b and 9c are spaced in parallel, and the shapes
thereof are respectively determined in accordance with head
operations set with respect to the camera head unit 21. In this
embodiment, the operating portion 9a is shaped like a projection,
and the operating portions 9b and 9c are flat. The input/output
terminal 10 is located adjacent to the operating portion 9c.
[0041] The pan head unit 22 is, as shown in FIG. 3, provided with a
pedestal 22a having a holding mechanism 42 for interchangeably
holding the camera head unit 21. The pedestal 22a is turned on the
horizontal axis (in a pan direction) and on the vertical axis (in a
tilt direction) by an optical axis controller 15. This movement of
the pedestal 22a changes the direction of the optical axis of the
camera head unit 21, that is, the image taking area.
[0042] The optical axis controller 15 comprises a horizontal driver
13 for driving the pedestal 22a in the pan direction, a horizontal
position detector 13a for detecting the drive amount of the
pedestal 22a in the pan direction, a vertical driver 14 for driving
the pedestal 22a in the tilt direction, and a vertical position
detector 14a for detecting the drive amount of the pedestal 22a in
the tilt direction. The structures of the horizontal driver 13 and
the vertical driver 14 will be described later.
[0043] The horizontal driver 13 and the vertical driver 14 are
controlled by a pan head controller 12, and the control amount is
determined by using the driving voltage and the driving speed. The
pan head controller 12 has a CPU (central processing unit; not
shown) and a memory (also not shown). The CPU determines the
aforesaid control amount for each of control modes previously
stored in the memory. The control mode is selected based on a
selection signal from a pan head control switching mechanism 11 as
will be described later. In this embodiment, as shown in FIG. 10,
eight control modes M1, . . . , M8 are selectable with reference to
the weight and the focal length of the lens 1 in the camera head
unit 21.
[0044] As the driving voltage in the control modes, one of three
patterns set in accordance with the weight of the zoom lens 1 as
shown in FIG. 11 is selected. The lens weight is divided into three
regions, i.e., above 600 g, 600 g to 300 g and below 300 g, and the
patterns of the driving voltage are set corresponding to the
respective regions of the lens weight. Similarly, as the driving
speed in the control modes, one of three patterns set in accordance
with the focal length of the zoom lens 1 is selected as shown in
FIG. 12. The focal length of the zoom lens 1 is divided into three
regions, a wide-angle lens focal length, a standard lens focal
length, and a telephoto lens focal length, and the patterns of the
driving speed are set corresponding to the respective regions. The
driving speed is set such as to decrease as the focal length
increases from the wide-angle lens to the telephoto lens.
[0045] The pan head control switching mechanism 11 provided on the
holding mechanism of the pedestal 22a has three terminals 11a, 11b
and 11c and an input/output terminal 17. The terminal 11a is
located to be opposed to the operating portion 9a of the control
terminal 9 when the camera head unit 21 is attached to the pedestal
22a. Similarly, the terminals 11b, and 11c are positioned
corresponding to the operating portions 9b and 9c of the control
terminal 9, respectively. The input/output terminal 17 is located
to be opposed to the input/output terminal 10.
[0046] The pan head control switching mechanism 11 also has a
bracket 32 attached to the holding mechanism 42 of the pedestal 22a
as shown in FIG. 5. The bracket 32 comprises the terminals 11a,
11b, and 11c, the input/output terminal 17, and a stopper 33 for
positioning the support member 31 of the camera head unit 21. The
terminals 11a, 11b and 11c are spaced in parallel.
[0047] The terminals 11a, 11b and 11c are each, as shown in FIGS. 6
and 7, turnably supported at one end thereof by a shaft 25 attached
to the bracket 32, urged by a spring member 27 at the center
thereof, and held in such a position that the other end thereof is
in contact with a part of the bracket 32 against the spring force
of the spring member 27 as shown in FIG. 7. Actuating switches 26
are respectively opposed to the other ends of the terminals 11a,
11b and 11c. When the terminal 11a, 11b or 11c is pressed by the
corresponding operating portion 9a, 9b or 9c as shown in FIG. 6,
the other end thereof presses the actuating switch 26, thereby
performing a turning-on operation. In other words, signals
generated in response to the turning-on operations of the actuating
switches 26 are given as selection signals to the pan head
controller 12, and the control mode is selected by the pan head
controller 12 according to the combination of these selection
signals. In short, selection signals for determining a proper
control mode to the camera head unit 21 are generated by choosing
respective shapes of the operating portions 9a, 9b and 9c such as
to make the corresponding actuating switches 26 perform turning-on
operations. In this embodiment, as mentioned above, eight control
modes M1, . . . , M8 are selectable with reference to the weight
and focal length of the lens 1 in the camera head unit 1. Since the
operating portion 9a projects and the operating portions 9b and 9c
are flat, the actuating switch 26 corresponding to the terminal 11a
performs a turning-on operation and the actuating switches 26
corresponding to the other terminals 11b and 11c do not perform any
turning-on operation, by which the control mode M1 is selected. The
control mode M1 is set under the condition that the lens weight is
less than 300 g and the focal length is standard.
[0048] When the bracket 32 is fitted on the support member 31 of
the camera head unit 21, the input/output terminal 17 is
electrically connected to the input/output terminal 10, by which
the camera controller 5 and the I/F controller 16 are connected
through the input/output terminals 10 and 17 so as to communicate
with each other.
[0049] The I/F controller 16 receives an operation control signal
from external equipment (such as a computer), and sends information
about the camera head unit 21 and the pan head unit 22 to the
external equipment. As is clear from the above description, the pan
head controller 12 is capable of communication with other devices
in the pan head unit 22.
[0050] The structure of the horizontal driver 13 will be described
in detail with reference to FIG. 8. FIG. 8 is a perspective view
showing the structure of the horizontal driver 13 in the image
input apparatus shown in FIG. 1.
[0051] The horizontal driver 13 has a stepper motor 51 supported by
a support member (not shown), as shown in FIG. 8. A worm gear 52 is
attached to an output shaft of the stepper motor 51 at one end, and
rotatably supported by a base 61 at the other end thereof. A
helical gear 53 mounted on a shaft 55 is meshed with the worm gear
52. Both ends of the shaft 55 are rotatably supported by
corresponding support plates 56.
[0052] A worm gear 54 and a disk 57 with a plurality of slits 58
are fixed on the shaft 55. A helical gear 62 mounted on a shaft 60
is meshed with the worm gear 54. The shaft 60 is supported
rotatably in the pan direction by the base 61.
[0053] The helical gear 62 is provided with a pin (not shown) which
projects toward the base 61 and actuates two microswitches 63
mounted on the base 61 in correlation to the rotation of the
helical gear 62. An initial position and an operation limit point
(position) in the pan direction of the shaft 60 are sensed by
actuating the microswitches 63 with the pin.
[0054] The disk 57 is located orthogonal to the optical path formed
by a photointerrupter 59 to open and shut the optical path. The
photointerrupter 59 detects a signal in response to the opening and
closing of the optical path, and the detection signal is given to
the horizontal position detector 13a. The horizontal position
detector 13a detects the rotation angle of the shaft 60 in the pan
direction based on the detection signal from the photointerrupter
59.
[0055] The structure of the vertical driver 14 will now be
described in detail with reference to FIG. 9. FIG. 9 is a
perspective view showing the structure of the vertical driver 14 in
the image input apparatus shown in FIG. 1.
[0056] The vertical driver 14 is mounted on an operation table 71
attached to the shaft 60 of the horizontal driver 13 as shown in
FIG. 9, and provided with a stepper motor 73.
[0057] An output shaft of the stepper motor 73 is attached to a
spur gear 74 which is meshed with a spur gear 75. The spur gear 75
is integrally fixed to a worm gear 76. Shaft portions 91 at both
ends of the worm gear 76 are rotatably supported by bearings 77
attached to the operation table 71, respectively.
[0058] The worm gear 76 is meshed with a helical gear 78 integrally
fixed to a bevel gear 79. The bevel gear 79 is meshed with a bevel
gear 80 mounted on a shaft 83. The shaft 83 is rotatably supported
at the center thereof by a bearing 84 fixed on the operation table
71.
[0059] Elliptic cams 88 are attached to both ends of the shaft 83,
and respectively fitted in cam grooves 90 formed on a camera head
fixing plate 89. The camera head fixing plate 89 is supported by
the shaft portions 91 of the worm gear 76 so as to pivot on the
shaft portions 91 in a tilt direction in correlation to the
movement of the cams 88.
[0060] The bevel gear 80 has a pin 81 which projects in parallel
with the shaft 83 and actuates two microswitches 82 and 92 in
correlation to the rotation of the bevel gear 80. The microswitches
82 and 92 are mounted on the operation table 71. An initial
position and an operation limit point (position) in the tilt
direction of the camera head fixing plate 89 are sensed by
actuating the microswitches 82 and 92 with the pin 81.
[0061] A disk 85 with a plurality of slits 86 is fixed on the shaft
83.
[0062] The disk 85 is located orthogonal to the optical path formed
by a photointerrupter 87 to open and shut the optical path. The
photointerrupter 87 detects a signal in response to the open and
shut of the optical path, and the detection signal is given to the
vertical position detector 14a. The vertical position detector 14a
detects the rotation angle of the camera head fixing plate 89 in
the tilt direction based on the detection signal from the
photointerrupter 87.
[0063] A pan head control switching operation in the image input
apparatus will now be described with reference to FIG. 13. FIG. 13
is a flowchart showing the pan head control switching operation in
the image input apparatus shown in FIG. 1.
[0064] When the camera head unit 21 is mounted on the pan head unit
22, as shown in FIG. 13, the support member 31 of the camera head
unit 21 (shown in FIG. 4) is fitted in the bracket 32 of the pan
head unit 22 (shown in FIG. 5) (Step S101).
[0065] The terminals 11a, 11b and 11c are pressed by the
corresponding operating portions 9a, 9b and 9c in correlation to
the fitting of the support member 31 and the bracket 32. Then, the
actuating switches 26 are pressed by the other ends of the
terminals 11a, 11b and 11c, thereby performing turning-on
operations. In other words, signals generated by the turning-on
operations of the actuating switches 26 are given as selection
signals to the pan head controller 12, and one of the control modes
M1, . . . , M8 is selected by the pan head controller 12 according
to the combination of these selection signals (step S102). In this
embodiment, the terminal 11a is pressed by the operating portion
9a, the actuating switch 26 corresponding to the terminal 11a
performs a turning-on operation, and other actuating switches 26 do
not perform any turning-on operations, by which the control mode M1
is selected.
[0066] Next, it is judged whether or not the selected control mode
is Mode M8 (Step S103). If the selected control mode is M8, that
is, if the camera head unit 21 is not mounted on the pan head unit
22, the process ends.
[0067] If the selected control mode is a mode other than M8, data
corresponding to the selected control mode is read from the memory
(Step S104), and the driving voltage in accordance with the lens
weight is set (Step S105). After setting the driving voltage, the
driving speed in accordance with the lens focal length is set (Step
S106).
[0068] Accordingly, when the camera head unit 21 is mounted on the
pan head unit 22, the driving voltage and driving speed best-suited
to the weight and focal length of the zoom lens 1 in the camera
head unit 1 are automatically selected. Specifically, when a light
lens is mounted, that is, when the camera head unit 21 is light,
the driving voltage is set at a low value, which achieves small
power consumption and reduced noise. When a wide-angle lens is
used, since the driving speed of the pan head unit 22 is set high,
an arbitrary subject can be captured instantaneously. When a
telephoto lens is used, a subject can be captured accurately by
driving the pan head unit 22 at low speed. As mentioned above, when
the camera head unit 21 is mounted on the pan head unit 22, the
optimum pan head operation with reference to the weight and focal
length of the zoom lens 1 in the camera head unit 21 can be
selected automatically, and the selection of the pan head operation
best-suited to the camera head unit 22 can be simplified.
[0069] Since the size of the camera head unit 21 capable of being
mounted on the pan head unit 22 is predetermined, there is no need
to excessively increase the driving force of the pan head unit 22
and the rise in cost of the pan head unit 22 can be restricted.
[0070] Furthermore, since the pan head unit 22 interchangeably
mounts the camera head unit 21 thereon, it is possible to select
the camera head unit 21 having a lens suited to the intended use
and to obtain high general versatility.
[0071] An optical axis control operation will now be described with
reference to FIG. 14. FIG. 14 is a flowchart showing an optical
axis control operation of the image input apparatus shown in FIG.
1.
[0072] After the camera head unit 21 is mounted on the pan head
unit 22, an external device for giving operation guidance to the
camera head unit 21 and the pan head unit 22 is connected to a
terminal I/F of the pan head unit 22 through a cable. After the
completion of the connection, the camera head unit 21 and the pan
head unit 22 are capable of operation.
[0073] Referring to FIG. 14, first, a command from the external
device is waited for (Step S202). When a command is input from the
external device, it is judged by the I/F controller 16 whether or
not the input command is a command relating to the pan head unit 22
(Step S203). If the input command is not a command relating to the
pan head unit 22, that is, if the input command is a command
relating to the camera head unit 21, the command is sent from the
I/F controller 16 to the camera controller 5 through the
input/output terminals 17 and 10. Based on the command, the zoom
operation of the zoom lens 1, the operation of the iris 2 and the
like are controlled (Step S214).
[0074] When the input command relates to the pan head unit 22, it
is judged whether or not the command is an initialization command
(Step S204). If the command is an initialization command, it is
sent to the pan head controller 22, which executes an
initialization process for setting the optical axis of the zoom
lens 1 in an initial position (Step S215). The initialization
process will be described in detail later.
[0075] If the input command is not an initialization command, that
is, if the input command is information for designating the angle
of the optical axis in the pan direction or the tilt direction, the
angle designated by the command is converted into positional
information (Step S205), and the positional information is stored
as a designated position in the memory (Step S206).
[0076] Subsequently, it is judged whether or not the current
position of the optical axis agrees with a designated position
(Step S207). If the optical axis is currently in the designated
position, the process from Step S201 on is executed again.
[0077] If the current position of the optical axis does not agree
with the designated position, the stepper motor 51 of the
horizontal driver 13 or the stepper motor 73 of the vertical driver
14 is driven to start the angle adjustment in the pan direction or
the tilt direction so that the optical axis reaches from the
current position to the designated position (Step S208).
[0078] After the angle adjustment in the pan direction or the tilt
direction is started, it is judged whether or not the horizontal
driver 13 or the vertical driver 14 reaches an operation limit
point before the optical axis reaches from the current position to
the designated position (Step S209). If it is judged that the
horizontal driver 13 or the vertical driver 14 reaches the
operation limit point before the optical axis reaches from the
current position to the designated position, a positional
information correction process is carried out to reset the
designated position stored in the memory (Step S210), and the
stepper motor 51 of the horizontal driver 13 or the stepper motor
73 of the vertical driver 14 is stopped (Step S212). After the
stepper motor 51 or 73 is stopped, the process from Step S201 on is
executed again.
[0079] If it is judged that the horizontal driver 13 or the
vertical driver 14 does not reach the operation limit point before
the optical axis reaches from the current position to the
designated position, the position of the optical axis is
sequentially updated by a computation such as addition or
substraction, and the stepper motor 51 of the horizontal driver 13
or the stepper motor 73 of the vertical driver 14 is driven until
the optical axis reaches from the current position to the
designated position (Step S211). When the optical axis reaches the
designated position, the current position stored in the memory is
updated (Step S213). After updating the current position, the
process from Step S201 on is executed again.
[0080] When the command input from the external device is a command
for the camera head unit 21, it is sent from the I/F controller 16
to the camera controller 5 through the input/output terminals 17
and 10. When the input command is a command for the pan head unit
22, it is sent from the I/F controller 16 to the pan head
controller 12. Accordingly, it is possible to combine a control
line for the camera head unit 21 and a control line for the pan
head unit 22 into one line, and thereby, to eliminate excess
trouble of separately laying the control lines for the camera head
unit 21 and the pan head unit 22 as in the conventional apparatus
in which a camera can be mounted on a pan head. Furthermore, since
the I/F controller 16 is set to communicate with the external
device, there is no need to add a special connecting device which
allows communication between the I/F controller 16 and the external
device.
[0081] Next, the initialization process for the pan head unit 22
will be described with reference to FIG. 15. FIG. 15 is a flowchart
showing an initialization process in the optical axis control
operation of the image input apparatus shown in FIG. 1.
[0082] In the initialization process, initialization in the
horizontal direction is first performed. When the initialization in
the horizontal direction is started, as shown in FIG. 15,
directions are given to make a turn in an A direction (for example,
a horizontal and clockwise direction), and the stepper motor 51 of
the horizontal driver 13 is driven (Step S301). The drive of the
stepper motor 51 in the horizontal driver 13 is continued until an
operation limit point of the shaft 60 is detected in response to
the actuation of the microswitch 63. When the operation limit point
is detected, the stepper motor 51 is stopped (Steps S302 and
S303).
[0083] When the stepper motor 51 is stopped, positional information
corresponding to the operation limit point is stored in the memory
(Step S304).
[0084] Next, directions are given to make a turn opposite to the A
direction (in a horizontal and counterclockwise direction), the
stepper motor 51 of the horizontal driver 13 is driven (Step S305),
and the current positional information is calculated by subtracting
positional information corresponding to the drive amount of the
stepper motor 51 from the positional information stored in the
memory (Step S306). The positional information corresponding to the
drive amount of the stepper motor 51 is found from the rotation
angle of the shaft 60 in the pan direction obtained based on the
above-mentioned detection signal of the photointerrupter 59.
[0085] The stepper motor 51 is driven until the calculated current
positional information agrees with predetermined information
designated and stored in the memory. When the current positional
information agrees with the designated information stored in the
memory, the stepper motor 51 is stopped (Steps S307, S308). After
the stop of the stepper motor 51, the initialization process in the
horizontal direction ends.
[0086] Subsequently, initialization in the vertical direction is
performed by using a similar procedure to the initialization in the
horizontal direction. The description of the initialization in the
vertical direction is omitted in this embodiment.
[0087] Thus, an absolute value of the optical axis of the zoom lens
1 can be detected and the direction of the optical axis can be set
arbitrarily by executing the initialization process.
[0088] Although the camera head unit 21 is moved by the operation
of the optical axis controller 15 in this embodiment, the camera
head unit 21 and the signal processing circuit 4 may be separated
from each other, a package for housing the zoom lens 1, the image
pickup device 3 and the like together may be driven by the optical
axis controller 15.
[0089] If there is no need to greatly change the image taking area
(position), a driving method for changing the relative position
between the zoom lens 1 and the image pickup device 3, a method of
changing the optical axis of incident light by placing a variable
vertical angle prism in front of the zoom lens 1, or a method of
changing the angle relative to the optical axis by placing a plate
glass member (whose opposite surfaces are parallel) in the optical
path may be adopted. Furthermore, mode information stored in the
memory may be read into the pan head unit when the camera head unit
is mounted on the pan head unit. Still further, more accurate
motion control can be exerted by storing information about the lens
weight, focal length and the like in the memory, not as mode
information, but as concrete numeric values.
[0090] The pan head in the above-mentioned embodiment is equipped
with a holding mechanism attached to a pedestal to interchangeably
hold an image pickup device, and a pan head control switching
mechanism for performing switching so as to select and control a
pan head operation suited to the image pickup device when the image
pickup device is mounted on the holding mechanism. The pan head
operation corresponding to the image pickup device is selected and
carried out by a drive means based on the switching operation of
the pan head control switching mechanism. Therefore, it is possible
to achieve an image input apparatus which is excellent in general
versatility and low in cost and is capable of changing pan head
control with no trouble.
[0091] In addition, since the pan head has an input/output terminal
to be connected to an input/output terminal of the image pickup
device for signals relating to control when the image pickup device
is mounted on the holding mechanism, the trouble of laying another
control line separate from a control line for the image pickup
device can be eliminated.
[0092] The individual components shown in outline or designated by
blocks in the Drawings are all well-known in the image recording
arts, and their specific construction and operation are not
critical to the operation or best mode for carrying out the
invention.
[0093] While the present invention has been described with respect
to what is presently considered to be the preferred embodiments, it
is to be understood that the invention is not limited to the
disclosed embodiments. To the contrary, the invention is intended
to cover various modifications and equivalent arrangements included
within the spirit and scope of the appended claims. The scope of
the following claims is to be accorded the broadest interpretation
so as to encompass all such modifications and equivalent structures
and functions.
* * * * *