Digital Camera Patent Abstract
A digital camera includes a position sensor which detects a position
of the camera body relative to the direction of gravity, an acceleration
sensor which detects an acceleration acted upon the camera body,
a memory in which image data of a captured image is recorded, and
a controller. If the magnitude of the acceleration detected by the
acceleration sensor when the captured image is produced is smaller
than a predetermined value, the controller records the image data
in the memory together with positional data of the camera body that
is detected by the position sensor. If the magnitude of the acceleration
detected by the acceleration sensor when the captured image is produced
is equal to or greater than the predetermined value, the controller
deems the data on the position of the camera body as invalid data
and records only the image data in the memory. Digital Camera Patent Claims
What is claimed is:
1. A digital camera comprising; a position sensor which detects
a position of a camera body of said digital camera relative to the
direction of gravity; at least one acceleration sensor which detects
acceleration acting upon said camera body; a memory in which image
data of a captured image is recorded; and a controller, wherein
if the magnitude of said acceleration detected by said at least
one acceleration sensor at the time said captured image is obtained
is smaller than a predetermined value, said controller records said
image data in said memory together with data on a position of said
camera body that is detected by said position sensor at the time
said captured image is obtained, and if the magnitude of said acceleration
detected by said at least one acceleration sensor at the time said
captured image is obtained is equal to or greater than said predetermined
value, said controller considers said data on said position of said
camera body as invalid data, records said image data in said memory,
and does not record said data on said position of said camera body
in said memory.
2. The digital camera according to claim 1, wherein said at least
one acceleration sensor comprises: a first acceleration sensor which
exclusively detects an acceleration in a horizontal direction; and
a second acceleration sensor which exclusively detects an acceleration
in a vertical direction perpendicular to said horizontal direction.
3. The digital camera according to claim 1, wherein said position
sensor comprises a ball, a surface layer of said ball comprising
a conductive material.
4. The digital camera according to claim 1, wherein said position
sensor comprises a ball, a light emitting element and more than
one light receiving element.
5. The digital camera according to claim 1, wherein when an acceleration
detected by said acceleration sensor is in a direction opposite
to the direction of gravity, said data on said position of said
camera is recorded regardless of the magnitude of said acceleration.
6. A camera comprising: a position sensor which detects a position
of a camera body of said camera relative to the direction of gravity;
at least one acceleration sensor which detects acceleration acting
upon the camera body; a memory in which image data of a captured
image is recorded; and a controller, which determines position data
of the camera body relative to the direction of gravity as invalid
data when it is determined that the magnitude of the acceleration
detected by said at least one acceleration sensor is equal to or
greater than a predetermined value and controls a camera function
to record said image data in said memory and to not record said
position data in said memory in accordance with said determination.
7. The camera according to claim 6, wherein said controller records,
in said memory, said image data and position data, detected by the
position sensor, when the magnitude of the acceleration detected
by said at least one acceleration sensor is smaller than a predetermined
value.
8. The camera according to claim 6, wherein said at least one acceleration
sensor comprises: a first acceleration sensor which detects an acceleration
in a horizontal direction; and a second acceleration sensor which
detects an acceleration in a direction substantially perpendicular
to said horizontal direction.
9. The camera according to claim 6, said position sensor including
a ball, a surface layer of said ball comprising a conductive material.
10. The camera according to claim 6, said position sensor including
a ball, a light emitting element and more than one light receiving
element.
11. The camera according to claim 6, wherein said controller records
the position data when the acceleration detected by said acceleration
sensor is in a direction opposite to the direction of gravity, regardless
of the magnitude of the acceleration.
12. A camera comprising: a position sensor which detects a position
of a camera body relative to the direction of gravity; at least
one acceleration sensor which detects acceleration acting upon the
camera body; and a controller, which records image data and position
data detected by the position sensor, when the magnitude of the
acceleration detected by said at least one acceleration sensor is
smaller than a predetermined value and does not record position
data together with image data when the magnitude of the acceleration
detected by said at least one acceleration sensor is equal to or
greater than the predetermined value.
13. The camera according to claim 12, wherein said at least one
acceleration sensor comprises: a first acceleration sensor which
detects an acceleration in a horizontal direction; and a second
acceleration sensor which detects an acceleration in a direction
substantially perpendicular to said horizontal direction.
14. The camera according to claim 12, wherein said position sensor
includes a ball, a surface layer of said ball comprising a conductive
material.
15. The camera according to claim 12, wherein said position sensor
includes a ball, a light emitting element and more than one light
receiving element.
16. The camera according to claim 12, wherein said controller records
the position data when the acceleration detected by said acceleration
sensor is in the opposite direction to the direction of gravity,
regardless of the magnitude of the acceleration.
Digital Camera Patent Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a digital camera having a position
sensor which detects the position or attitude of the camera body
(e.g., horizontal or vertical position) relative to the direction
of gravity.
2. Description of the Related Art
Digital cameras having record and playback modes that are provided
with a position sensor for detecting the position (e.g., horizontal
or vertical position) of the camera body relative to the direction
of gravity are known in the art. In such known digital cameras,
a captured image is recorded as image data together with corresponding
position data in a record mode so that the reproduced image is indicated
on a display monitor at an easy-to-see orientation (i.e., in such
a manner that the upper and lower ends [vertical orientation] of
a display monitor substantially coincide with the actual upper and
lower positions [vertical orientation] of the reproduced image)
in accordance with the corresponding recorded position data in playback
mode.
Among such conventional digital cameras, especially in cameras
that are provided with a ball-contact type inclination sensor as
the position sensor for detecting the position of the camera body
relative to the direction of gravity, it is sometimes the case that
the inclination sensor cannot detect the position of the camera
body properly if a picture is taken (namely, an image is captured)
with an acceleration other than the acceleration of gravity (gravitational
acceleration) being acted upon the camera body, e.g., if an image
is captured while the camera is panned quickly. For instance, when
an image is captured with the camera being held horizontally while
the camera is panned quickly, the inclination sensor may erroneously
determine that the camera is in a vertical position because of the
acceleration acted upon the camera in a lateral direction while
the camera is panned. If the inclination sensor erroneously detects
the position of the camera body, image data is recorded together
with incorrect position data, which results in the reproduced image
being indicated on a display monitor at an difficult-to-see orientation
in playback mode.
SUMMARY OF THE INVENTION
The present invention has been made in view of the aforementioned
problems that reside in conventional digital cameras having a position
sensor which detects the position or attitude of the camera body
relative to the direction of gravity. An object of the present invention
is to provide a digital camera having a position sensor which correctly
detects the position of the camera body even if an acceleration
other than the acceleration of gravity is acted upon the camera
body when an image is captured while the camera is swung (e.g.,
panned) quickly, so that the reproduced image can be indicated on
a display monitor in an easy-to-see orientation in playback mode
at all times.
To achieve the object mentioned above, according to the present
invention, a digital camera is provided, including a position sensor
which detects a position of a camera body of the digital camera
relative to the direction of gravity; at least one acceleration
sensor which detects an acceleration acted upon the camera body;
a memory in which image data of a captured image is recorded; and
a controller. If the magnitude of the acceleration detected by the
at least one acceleration sensor, at the time the captured image
is produced, is smaller than a predetermined value, the controller
records the image data in the memory together with data on a position
of the camera body that is detected by the position sensor at the
time the captured image is produced. If the magnitude of the acceleration
detected by the at least one acceleration sensor at the time the
captured image is produced is equal to or greater than the predetermined
value, the controller deems the data on the position of the camera
body as invalid data and records only the image data in the memory.
Preferably, the at least one acceleration sensor includes a first
acceleration sensor which exclusively detects an acceleration in
a horizontal direction and a second acceleration sensor which exclusively
detects an acceleration in a vertical direction perpendicular to
the horizontal direction.
In an embodiment, the position sensor includes a ball, a surface
layer thereof being made of a conductive material.
In an embodiment, the position sensor includes a ball, a light
emitting element and more than one light receiving element.
In the case where an acceleration detected by the acceleration
sensor is in the opposite direction to the direction of gravity,
the data on the position of the camera is recorded regardless of
the magnitude of the acceleration.
The present disclosure relates to subject matter contained in Japanese
Patent Application No. 2000-001378 (filed on Jan. 7, 2000) which
is expressly incorporated herein by reference in its entirety.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be discussed below in detail with reference
to the drawings, in which:
FIG. 1 is a flow chart of a control process performed by a system
controller provided in a digital camera shown in FIG. 3 to which
the present invention is applied;
FIG. 2 is a block diagram of a circuit provided in the digital
camera shown in FIG. 3;
FIG. 3 is a perspective view of the digital camera of the present
invention;
FIG. 4 is a schematic diagram of an inclination sensor provided
in the digital camera shown in FIG. 3, in a state where the photographing
lens of the digital camera is orientated in a upward or downward
at an exact gravitational direction;
FIG. 5 is a schematic diagram of an inclination sensor provided
in the digital camera shown in FIG. 3, in a state where the digital
camera is held upside down;
FIG. 6 is a schematic diagram of an inclination sensor provided
in the digital camera shown in FIG. 3, in a state where the digital
camera is held in a first vertical position;
FIG. 7 is a schematic diagram of an inclination sensor provided
in the digital camera shown in FIG. 3, in a state where the digital
camera is held in a second vertical position;
FIG. 8 is a schematic diagram of an inclination sensor provided
in the digital camera shown in FIG. 3, in a state where the digital
camera is held in a normal horizontal position;
FIG. 9 is a schematic diagram of switches of the inclination sensor
shown in FIGS. 4 through 8;
FIG. 10 is a schematic diagram of a system controller and the switches
of the inclination sensor, showing the structure of connection therebetween;
FIG. 11 is an embodiment of a time chart of pulse signals which
are output from the system controller shown in FIG. 10 to be input
to the inclination sensor, and pulse signals which are output from
the inclination sensor to be input to the system controller;
FIG. 12 is a schematic view of the digital camera shown in FIG.
3 and a person as a subject to be photographed, showing a state
of taking a picture of the person with the digital camera being
held vertically;
FIG. 13 is a schematic rear view of the digital camera shown in
FIG. 3, showing a state where an image of the person that is recorded
by the digital camera in the state shown in FIG. 12 is reproduced
to be indicated on an LCD monitor of the digital camera with the
digital camera in a horizontal position;
FIG. 14 is a schematic diagram of another embodiment of an inclination
sensor;
FIG. 15 shows a perspective view of a semiconductor acceleration
detecting device; and
FIG. 16 shows a side elevation of the semiconductor acceleration
detecting device shown in FIG. 15.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 is a perspective view of an embodiment of a digital camera
10 to which the present invention is applied. The digital camera
10 is provided at the front of a camera body 12 with a photographing
lens 14. The digital camera 10 is provided on top of the camera
body 12 with a release button 16, an LCD panel 18, and a set of
function buttons 20. The LCD panel 18 indicates various settings
and photographic information of the camera body 12.
The digital camera 10 is provided, at the rear of the camera body
12 at the center of the rear face thereof, with a horizontally-elongated
rectangular color LCD monitor (display monitor) 22. A monitoring
image (video image) of the subject (object) is indicated on the
LCD monitor 22 in record mode, while a captured image is reproduced
to be indicated on the LCD monitor 22 in playback mode.
The digital camera 10 is provided at the rear of the camera body
12 with a mode select dial 24 (see FIGS. 12 and 13). The user can
select either a record mode or a playback mode by operating the
mode select dial when the power switch (not shown) of the digital
camera 10 is ON.
The digital camera 10 is provided therein with an inclination sensor
(position sensor) 50 (see FIG. 4 through 8) which detects the position/attitude
(e.g., a horizontal or vertical position) of the camera body 12
relative to the direction of gravity. In the digital camera 10,
image data of a captured image (captured image data) is recorded
together with corresponding position data in a memory (nonvolatile
RAM such as a flash memory) provided in a PC card 44 in record mode
so that the reproduced image of the recorded image data is indicated
on the LCD monitor 22 in an easy-to-see orientation (i.e., in such
a manner that the upper and lower ends of the LCD monitor 22 substantially
coincide with the actual upper and lower positions of the reproduced
image) in accordance with the corresponding recorded position data
in playback mode.
For instance, if the user takes a picture of a person (subject)
"S" while holding the camera 10 vertically in record mode
as shown in FIG. 12, the recorded image of the person "S"
is reproduced to be indicated on the LCD monitor 22 in such a manner
as shown in FIG. 13, so that the upper and lower ends of the LCD
monitor 22 substantially coincide with the actual upper and lower
positions of the reproduced image in playback mode. Furthermore,
since the display monitor is normally rectangular or square, data
which distinguishes which side out of four sides of the display
monitor is an upper and lower side during a photographic operation
is only required.
The digital camera 10 is provided therein with two acceleration
sensors, i.e., first and second acceleration sensors 71 and 72.
The first acceleration sensor exclusively detects an acceleration
in the horizontal direction, while the second acceleration sensor
72 exclusively detects an acceleration in the vertical direction
perpendicular to the horizontal direction (see FIG. 3). The first
and second acceleration sensors 71 and 72 are fixed to a substrate
70 provided in the camera body 12. When the digital camera 10 is
set at a normal horizontal position, the first acceleration sensor
71 detects the acceleration in the direction of gravity (vertical
direction or upward/downward direction), and the second acceleration
sensor 72 detects the acceleration in a left/right direction (horizontal
direction) of the camera body 12.
The first and second acceleration sensors (semiconductor acceleration
detecting devices) 71 and 72 will herein be described with reference
to FIGS. 15 and 16. FIG. 15 shows a perspective view of a semiconductor
acceleration detecting device. In FIGS. 15 and 16, the semiconductor
acceleration detecting device includes an acceleration detecting
arm 101 which converts applied acceleration into electric signals;
a base 102 of the semiconductor acceleration detecting device; a
base seat 103 which has one end of the acceleration detecting arm
101 attached on the upper side thereof, and the lower surface thereof
is fixed to the base 102 to thereby support the acceleration detecting
arm 101; a weight 104 which is attached to the other end of the
acceleration detecting arm 101; read-pins 105 for reading the electric
signals output by the acceleration detecting arm 101 for external
output of the semiconductor acceleration detecting device; wires
106 which transport the electric signals from the accelerations
detecting arm 101 to the read-pins 105; a pad 107 for soldering
the wires 106 which transport the electric signals from the accelerations
detecting arm 101 to the read-pins 105; an acceleration detecting
area 108 which forms a bridge circuit that converts acceleration
into electric signals; and an adhesive 109. Since the acceleration
detecting arm 101 is fixed at one end by the base seat 103, when
acceleration is applied to the semiconductor acceleration detecting
device in direction of arrow A, the acceleration detecting arm 101
bends due to inertia. Furthermore, since the weight 104 is attached
to the other end of the acceleration detecting arm 101, the above-mentioned
bending is further increased thereby. When the acceleration detecting
arm 101 bends, the acceleration detecting area 108 deforms, and
internal stress thereof occurs. The electrical equilibrium state
of the bridge circuit (constructed from a resistor wherein a piezo
resistance effect occurs due to the above-mentioned stress) is broken,
so that the electric potential difference thus produced can be converted
into electric signals. Thereafter, these electric signals are output
to the filter/amplifier circuit 74 from the pad 107 via the wires
106 and the read-pins 105.
FIG. 2 shows a circuit diagram of the digital camera 10. The digital
camera 10 is provided therein with a system controller 30 which
exclusively controls the overall operations of the digital camera
10. The system controller 30 is provide from a microcomputer. The
digital camera 10 is further provided therein with a release switch
17 and a set of switches 33 which are connected to the system controller
30. The release switch 17 is associated with the release button
16, and the set of switches 33 are respectively associated with
the set of function buttons 20. The aforementioned LCD panel 18
is connected to the system controller 30. The digital camera 10
is further provided therein with a filter/amplifier circuit 73,
a filter/amplifier circuit 74, a CCD driver, 35, an image processing
circuit 36 and a card I/F which are all connected to the system
controller 30. The inclination sensor 50 is connected to the system
controller 30 via the filter/amplifier circuit 73, while the first
and second acceleration sensors 71 and 72 are connected to the system
controller 30 via the filter/amplifier circuit 74.
The digital camera 10 is provided therein with a CCD image sensor
38 as an image pick-up device which is connected to the image processing
circuit 36 via an A/D converter 39. Upon a depression of the release
button 16, the image processing circuit 36 drives the CCD sensor
38 via a CCD driver 35 so that the object image focused on the sensitive
surface of the CCD image sensor 38 is converted thereby into a picture
signal. This picture signal read out of the CCD image sensor 38
is converted into a corresponding digital signal by the A/D converter
39. The image processing circuit 36 receives the digital signal
from the A/D converter 39 to apply a predetermined image process
to the digital signal to obtain image data. This image data is normally
recorded in an image memory (buffer storage) 40. Image data making
up at least one photographic picture which is written in the image
memory 40 is recorded on the PC card 44.
The PC card 44 is connected to the card I/F 37 via the card driver
75 and the card connector 76. The image processing circuit 36 can
record the captured image data in the PC card 44 via the card I/F
37, the card driver 75 and the card connector 76. The image processing
circuit 36 can also transfer the image data recorded in the PC card
44 to the image memory 40 via the card I/F 37, the card driver 75
and the card connector 76.
Furthermore, when the image data is record on the PC card 44, the
vertical direction data detected by the inclination sensor 50, shutter
data, diaphragm value, date and time the photo was taken are also
recorded as supplementary data.
A monitor I/F 41 is connected to the image processing circuit 36.
Image data that is transmitted from the PC card 44 to the image
memory (buffer storage) 40 is input to the monitor I/F 41 via the
image processing circuit 36 in playback mode, while the monitoring
image (motion video image) of the object which is focused on the
CCD image sensor 38 is input to the monitor I/F 41 via the image
processing circuit 36 in record mode. In each of record mode and
playback mode, the image data is output to the LCD monitor 22 via
the LCD driver 42 to be indicated as a reproduced image on the LCD
monitor 22.
The structure of the inclination sensor 50, which detects the position
of the camera body 12 relative to the direction of gravity, will
be discussed in detail with reference to FIGS. 4 through 10. FIGS.
4 through 8 each show the structure of the inclination sensor 50.
The inclination sensor 50 is fixedly mounted on the substrate 48
disposed in the camera body 12 (see FIG. 3) so that the top, bottom,
right and left of each drawing of FIGS. 4 through 8 substantially
correspond to the top, bottom, right and left of the camera body
12 (top, bottom, left and right as viewed in FIG. 3), respectively.
The inclination sensor 50 is provided with first through fourth
contacts 51, 52, 53 and 54 arranged as shown in each of FIGS. 4
through 8. The inclination sensor 50 is provided, in the space surrounded
by the four contacts 51 through 54, with a metal ball 55. At least
the surface layer of the metal ball 55 is made of a conductive material.
Each of the first through fourth contacts 51 through 54 is connected
to the system controller 30.
The front and rear openings of the space surrounded by the first
through fourth contacts 51 through 54 (the two openings provided
away from the page of FIG. 4 in a direction perpendicular to the
page), have enough distance therebetween so as to allow the metal
ball 55 to move freely within the space, i.e., the space is closed
off by lids 57a and 57b which are formed from an insulating material
provided apart from each other at a distance slightly larger than
the diameter of the metal ball 55. The inclination sensor 50 is
constructed so as to encase the four contacts 51 through 54 in a
box (case), and one of the lids 57a or 57b can be formed as a base
of the box. Alternatively, one of the lids 57a or 57b can be formed
by the substrate 48. Furthermore, the lids 57a and 57b can have
a concave shape (respect to the metal ball 55) in the center portion
thereof so as to bulge outwards when viewed externally. Preferably,
the lids 57a and 57b have a concave shape (respect to the metal
ball 55) in the center portion thereof with a radius of curvature
larger than that of the metal ball 55, so as to bulge outwards when
viewed externally.
If the digital camera 10 is held in a normal horizontal position
as shown in FIG. 13, the metal ball 55 sits still at the position
shown in FIG. 8, so that the third and fourth contacts 53 and 54
are short-circuited via the metal ball 55. If the digital camera
10 is held in a first vertical position (i.e., a position of the
camera body 12 shown in FIG. 12 that is rotated clockwise about
the optical axis of the photographing lens 14 by 90 degrees from
the horizontal position shown in FIG. 13), the metal ball 55 sits
still at the position shown in FIG. 6, so that the second and fourth
contacts 52 and 54 are short-circuited via the metal ball 55.
If the digital camera 10 is held in a second vertical position
(i.e., a position of the camera body 12 that is rotated counterclockwise
about the optical axis of the photographing lens 14 by 90 degrees
from the horizontal position shown in FIG. 13), the metal ball 55
sits still at the position shown in FIG. 7, so that the first and
third contacts 51 and 53 are short-circuited via the metal ball
55. If the digital camera 10 is held upside down (i.e. a position
of the camera body 12 that is rotated clockwise or counterclockwise
about the optical axis of the photographing lens 14 by 180 degrees
from the horizontal position shown in FIG. 13), the metal ball 55
sits still at the position shown in FIG. 5, so that the first and
second contacts 51 and 52 are short-circuited via the metal ball
55. Moreover, if the digital camera 10 is held with the photographing
lens 14 being orientated in a fully upward or downward direction,
the metal ball 55 stays still at the position shown in FIG. 4, so
that none of the first through fourth contacts 51 through 54 are
short-circuited.
Accordingly, in the inclination sensor 50, the first and third
contacts 51 and 53 together constitute a first switch SW1, the first
and second contacts 51 and 52 together constitute a second switch
SW2, the second and fourth contacts 52 and 54 together constitute
a third switch SW3, and the third and fourth contacts 53 and 54
together constitute a fourth switch SW4. Each of the first through
fourth switches SW1, SW2, SW3 and SW4 is turned ON when the metal
ball 55 contacts thereto, and is turned OFF when the metal ball
55 does not contact thereto.
The system controller 30 is provided with first through fourth
terminals 1, 2, 3 and 4 which are connected to the first through
fourth contacts 51, 52, 53 and 54, respectively. FIG. 10 is a schematic
diagram of a system controller 30 and the first through fourth switches
SW1, SW2, SW3 and SW4 of the inclination sensor 50, showing the
structure of connection between the first through fourth terminals
1, 2, 3 and 4 and the switches SW1, SW2, SW3 and SW4.
FIG. 11 is an embodiment of a time chart of pulse signals which
are output from the system controller 30 to be input to the inclination
sensor 50, and pulse signals which are output from the inclination
sensor 50 to be input to the system controller 30. In this embodiment,
the system controller 30 regularly outputs a first pulse signal
61 from the second terminal 2 to be input to the second contact
52. At the same time, the system controller 30 regularly outputs
a second pulse signal 62 from the third terminal 3 to be input to
the third contact 53. It can be understood from the connecting structure
shown in FIG. 10 that the first pulse signal 61 output from the
second terminal 2 is output from the first terminal 1 at the time
the second switch SW2 is turned ON or the fourth terminal 4 at the
time the third switch SW3 is turned ON. Likewise, the second pulse
signal 62 output from the third terminal 3 is output from the first
terminal 1 at the time the first switch SW1 is turned ON or the
fourth terminal 4 at the time the fourth switch SW4 is turned ON.
The system controller 30 continuously monitors the first and fourth
terminals 1 and 4 to check whether any signals are input thereto.
The system controller 30 determines that the second switch SW2 has
been turned ON (i.e., that the digital camera 10 is held upside
down) upon detecting that the first pulse signal 61 output to the
second terminal 2 is input from the first terminal 1. The system
controller 30 determines that the third switch SW3 has been turned
ON (i.e., the digital camera 10 is held in a position shown in FIG.
12 that is rotated clockwise about the optical axis of the photographing
lens 14 by 90 degrees from the horizontal position) upon detecting
that the first pulse signal 61 output to the second terminal 2 is
input from the fourth terminal 4. The system controller 30 determines
that the first switch SW1 has been turned ON (i.e., the digital
camera 10 is held in a position rotated counterclockwise about the
optical axis of the photographing lens 14 by 90 degrees from the
horizontal position) upon detecting that the second pulse signal
62 output to the third terminal 3 is input from the first terminal
1. The system controller 30 determines that the fourth switch SW4
has been turned ON (i.e., that the digital camera 10 is held in
a normal horizontal position) upon detecting that the second pulse
signal 62 output to the third terminal 3 is input from the fourth
terminal 4.
FIG. 1 is a flow chart of a control process performed by the system
controller 30. In this control process, firstly it is determined
whether the power of the digital camera 10 is ON (step S1). Control
proceeds to the operation at step S3 if the power is ON or repeats
the operation at step S1 if the power is OFF. If it is determined
at step S1 that the power is ON, it is determined whether record
mode has been selected (step S3). If the record mode has been selected,
control enters a record mode process ("Record Mode Process")
in which it is firstly determined whether the release switch 17
is ON (step S5).
If it is determined at step S5 that the release switch 17 is ON,
it is determined whether the magnitude of an acceleration detected
by the first acceleration sensor 71 is equal to or greater than
a predetermined value (step S7). If it is determined at step S7
that the magnitude of an acceleration detected by the first acceleration
sensor 71 is smaller than the predetermined value, it is determined
whether the magnitude of an acceleration detected by the second
acceleration sensor 72 is equal to or greater than a predetermined
value (step S9). If it is determined that the magnitude of each
of the accelerations detected by the first and second acceleration
sensors 71 and 72 is smaller than the predetermined value, control
proceeds to step S11 at which the position or altitude of the camera
body 12 is detected by the inclination sensor 50. Subsequently,
captured image data is recorded together with data on the detected
position (position data) of the camera body 12 in the memory in
the PC card 44 (step S13). The system controller 30 determines the
actual upper and lower positions of each captured image in accordance
with the corresponding position data recorded in the memory in the
PC card 44.
If it is determined at step S7 that the magnitude of an acceleration
detected by the first acceleration sensor 71 is equal to or greater
than the predetermined value, the position data detected by the
inclination sensor 50 at the time the image is captured is regarded
as invalid data, so that only captured image data is recorded in
the memory in the PC card 44 (step S15). This process is performed
due to the following reason. When an image is captured with the
digital camera 10 being held horizontally while the digital camera
10 is panned, an acceleration is acted upon the digital camera 10
in a lateral direction. If the magnitude of an acceleration acted
upon the digital camera 10 in a lateral direction is greater than
a predetermined value, the metal ball 55 in the inclination sensor
50 does not stay still at the position shown in FIG. 8 even if the
camera body 12 is held horizontally. This prevents the third and
fourth contacts 53 and 54 from being short-circuited via the metal
ball 55. Furthermore, if the magnitude of an acceleration acted
upon the digital camera 10 in a lateral direction is very large,
the metal ball 55 may move to the position shown in FIG. 6 or 7.
Accordingly, if the magnitude of an acceleration acted upon the
digital camera in a lateral direction is greater than a predetermined
value, the inclination sensor may wrongly determine that the digital
camera is in a vertical position even if the digital camera is held
horizontally. To prevent this problem from occurring, according
to the present embodiment of the digital camera 10, if the magnitude
of an acceleration detected by the first acceleration sensor 71
is equal to or greater than the predetermined value, the position
data detected by the inclination sensor 50 at the time the image
is captured is regarded as invalid data, so that only captured image
data is recorded in the memory in the PC card 44.
If it is determined at step S9 that the magnitude of an acceleration
detected by the second acceleration sensor 72 is equal to or greater
than a predetermined value, the position data detected by the inclination
sensor 50 at the time the image is captured is regarded as invalid
data, similar to the operation at step S7, so that only captured
image data is recorded in the memory in the PC card 44 (step S15).
This process is performed due to the following reason. When a picture
is captured with the digital camera 10 being held horizontally while
the digital camera 10 is moved vertically, an acceleration is acted
upon the digital camera 10 in a vertical direction. If the magnitude
of an acceleration acted upon the digital camera 10 in a vertical
direction is greater than a predetermined value, the metal ball
55 in the inclination sensor 50 does not sit still at the position
shown in FIG. 8 even if the camera body 12 is held horizontally.
This prevents the third and fourth contacts 53 and 54 from being
short-circuited via the metal ball 55. Furthermore, if the magnitude
of an acceleration acted upon the digital camera 10 in a vertical
direction is very large, the metal ball may move to the position
shown in FIG. 5. Accordingly, if the magnitude of an acceleration
acted upon the digital camera in a vertical direction is greater
than a predetermined value, the inclination sensor may wrongly determine
that the digital camera is held upside down even if the digital
camera is held horizontally. To prevent this problem from occurring,
according to the present embodiment of the digital camera 10, if
the magnitude of an acceleration detected by the second acceleration
sensor 72 is equal to or greater than the predetermined value, the
position data detected by the inclination sensor 50 at the time
the image is captured is also regarded as invalid data, so that
only captured image data is recorded in the memory in the PC card
44.
Furthermore, in the case where the camera 10 is rotated upwards
(upward panning) in a direction against the direction of gravity,
since the metal ball 55 does not move from the lowest position in
the direction of gravity, there is less chance of the inclination
sensor 50 from erroneously detecting the attitude of the camera
10. Accordingly, since it can be determined whether the camera 10
is being panned upward by the detected position of the metal ball
55 before the detecting of the acceleration sensors 71 and 72 and
by when the direction of acceleration is detected by the acceleration
sensors 71 and 72, an arrangement can be provided so that when the
camera 10 is being panned upwards, the data on the detected position
(position data) of the camera body 12 can be recorded.
If it is determined at step S3 that record mode has not been selected,
it is determined whether playback mode has been selected (step S17).
If playback mode has been selected, control proceeds to a playback
mode process ("Playback Mode Process"). If playback mode
has not been selected, control returns to step S3.
As can be understood from the above discussion, according to the
digital camera 10 to which the present invention is applied, captured
image data is not recorded together with incorrect position data
detected by the inclination sensor 50 when the image is captured
with an acceleration being acted on the digital camera 10 whose
magnitude is equal to or greater than a predetermined value.
The present invention is not limited solely to the above illustrated
embodiment. For instance, the inclination sensor 50 can be replaced
by any other sensor which can detect the position or attitude of
the digital camera 10. For instance, an inclination sensor 80 shown
in FIG. 14 can be used instead. The inclination sensor 80 is composed
of an LED (light emitting element) 81, two phototransistors (light
receiving elements) 82 and 83, and a ball 55'. In this embodiment,
if the inclination sensor 80 is rotated counterclockwise by 90 degrees
as viewed in FIG. 14, it is determined that the digital camera is
in a vertical position because the light emitted from the LED 81
to be incident on the phototransistor 82 is interrupted by the ball
55'. Likewise, if the inclination sensor 80 is rotated clockwise
by 90 degrees as viewed in FIG. 14, it is determined that the digital
camera is in another vertical position because the light emitted
from the LED 81 to be incident on the phototransistor 83 is interrupted
by the ball 55'. Furthermore, if the inclination sensor 80 is rotated
clockwise or counterclockwise by 180 degrees with respect to the
orientation of FIG. 14; namely, if the inclination sensor 80 is
positioned upside down, it is determined that the digital camera
is held upside down because the light emitted from the LED 81 to
enter the space in the inclination sensor 80 is interrupted by the
ball 55'.
Each of the acceleration sensors 71 and 72 can be replaced by any
other device which can detect an acceleration acted upon the camera
body.
As can be understood from the foregoing, according to the digital
camera having a inclination sensor (position sensor) to which the
present invention is applied, since the controller deems the data
on the position of the camera body as invalid data and records only
the image data in the memory if the magnitude of the acceleration
detected by the at least one acceleration sensor at the time the
captured image is produce is equal to or greater than the predetermined
value, the position sensor does not erroneously detect the position
of the camera body even if an acceleration other than the acceleration
of gravity is acted upon the camera body when an image is captured
while the camera is swung (e.g., panned), so that the reproduced
image can be indicated on a display monitor at an easy-to-see orientation
in playback mode at all times.
Obvious changes may be made in the specific embodiments of the
present invention described herein, such modifications being within
the spirit and scope of the invention claimed. It is indicated that
all matter contained herein is illustrative and does not limit the
scope of the present invention. |