Digital Camera Patent Abstract
In a digital camera having a self-timer function, the time for which
the shot image is displayed in a self-timer shooting mode is longer
than the time for which the shot image is displayed in a normal
shooting mode. Digital Camera Patent Claims
What is claimed is:
1. A digital camera comprising: an image sensor for shooting a
subject; a selector for selecting a predetermined shooting mode,
wherein the shooting mode is a mode in which shooting is performed
after a first predetermined time has elapsed from an instruction
to start shooting; a first display controller for displaying a shot
image on a display for a second predetermined time when the shooting
mode is not selected; and a second display controller for displaying
a shot image on the display for a third predetermined time being
longer than the second predetermined time when the shooting mode
is selected.
2. A digital camera as claimed in claim 1, wherein the third predetermined
time is variable.
3. A digital camera as claimed in claim 2, wherein the first predetermined
time is variable, and the third predetermined time is changed in
accordance with the first predetermined time.
4. A digital camera as claimed in claim 1, wherein the third predetermined
time is longer than the first predetermined time.
5. A digital camera as claimed in claim 1, further comprising a
display discontinuing member for ending the display of the shot
image on the display even before the third predetermined time has
elapsed.
6. A digital camera as claimed in claim 5, wherein the display
discontinuing member is the selector.
7. A digital camera as claimed in claim 1, wherein the first and
second display controllers display the shot image on the display
after shooting is finished.
8. A digital camera as claimed in claim 1, wherein the predetermined
shooting mode is a self-timer shooting mode.
9. An image display method in digital camera, comprising: shooting
a subject; selecting a predetermined shooting mode, wherein the
shooting mode is a mode in which shooting is performed after a first
predetermined time has elapsed from an instruction to start shooting;
displaying a shot image on a display for a second predetermined
time when the shooting mode is not selected; and displaying a shot
image on the display for a third predetermined time being longer
than the second predetermined time when the shooting mode is selected.
Digital Camera Patent Description
This application is based on the application No. 11-261888 filed
in Japan, the content of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a digital camera having a self-timer
shooting function and an image display function.
2. Description of the Related Art
In resent years, digital cameras have rapidly been becoming widespread,
and various types of digital cameras are supplied to the market.
Generally, a digital camera frequently has an image display device
comprising a liquid crystal display (hereinafter, referred to as
an LCD) or the like on its back. Because of the LCD, the photographer
can confirm the image to be shot without viewing through the finder.
Therefore, it is possible to shoot the subject at an extremely free
angle. Moreover, a conventional digital camera is provided with
a function to continue displaying the shot image on the image display
device for a predetermined time every time one frame is shot, that
is, a function to hold the shot image for a predetermined time.
Because of this function, the photographer can check whether the
shot image is desired or not without performing any complicated
operations.
Whether silver halide film cameras or digital cameras, cameras
are frequently provided with a function to perform shooting by use
of a self-timer (hereinafter, referred to as a self-timer function).
According to the self-timer function which is used, for example,
when the photographer himself or herself is the subject to be shot,
shooting is on standby for a predetermined time after the depression
of the release button, and shooting is performed after the predetermined
time has elapsed. Because of this function, the photographer can
shoot himself or herself by moving to the position of shooting within
the predetermined time after depressing the release button.
However, since the photographer is the subject when self-timer
shooting is performed as mentioned above, it takes time for the
photographer to return to the camera after shooting is performed.
Therefore, even though the digital camera has the image display
device and the function to display the shot image for a predetermined
time, it frequently occurs that the display of the shot image ends
before the photographer returns to the camera to check the display
device on the back of the camera. That is, the photographer cannot
check the shot image. Since recorded images can be read out from
a recording medium and played back, the shot image can be checked
by playing it back. However, complicated operations-such as switching
to a reproduction mode and specification of the frame to be played
back are necessarily performed every time, which is inconvenient.
In view of the above-mentioned problem, an object of the present
invention is to provide a digital camera in which the photographer
can easily check whether the shot image is desired or not without
performing any complicated operations even when self-timer shooting
is performed.
SUMMARY OF THE INVENTION
To achieve the above-mentioned object, a digital camera according
to the present invention is provided with: an image sensor for shooting
a subject; a selector for selecting a predetermined shooting mode,
wherein the shooting mode is a mode in which shooting is performed
after a first predetermined time has elapsed from an instruction
to start shooting; a first display controller for displaying a shot
image on a display for a second predetermined time when the shooting
mode is not selected; and a second display controller for displaying
a shot image on the display for a third predetermined time being
longer than the first predetermined time when the shooting mode
is selected.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following description, like parts are designated by like
reference numbers throughout the several drawings:
FIGS. 1(a) and 1(b) are schematic perspective views of a digital
camera according to the present invention obliquely looked down
on from the front;
FIG. 2 is a schematic perspective view of the digital camera according
to the present invention obliquely looked down on from the rear;
FIG. 3 is a block diagram showing the general structure of the
digital camera according to the present invention;
FIG. 4 is a flowchart showing the release sequence in a first embodiment;
FIG. 5 is a flowchart showing the release sequence in a second
embodiment; and
FIG. 6 is a flowchart showing a self-timer shooting standby time
confirmation sequence.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A digital camera according to the present invention will be described
with reference to FIGS. 1 to 6. FIGS. 1(a) and 1(b) are schematic
perspective views of the digital camera according to the present
invention obliquely looked down on from the front. FIG. 1(a) shows
the camera in an activated state. FIG. 1(b) shows the camera in
a deactivated state. As shown in FIGS. 1(a) and 1(b), the digital
camera according to the present invention has a lens barrel 3 for
holding a taking lens 2 on the front surface of a camera body 1.
The lens barrel 3 protrudes from the camera body 1 when the camera
is activated, and collapses into the camera body 1 when the camera
is deactivated. Because of this structure, the camera is very compact
when deactivated, which provides excellent carryability. Moreover,
when the camera is deactivated, a lens barrier 11 is closed so that
the taking lens 2 is covered. Because of this structure, the taking
lens 2 can be prevented from being inadvertently made dirty or broken
when the camera is carried. In addition to the above-described members,
a finder window 4, an AF unit 5 for automatic focus detection and
a flash 6 are provided on the front surface of the camera body 1.
On the top surface of the camera body 1, operation members 7 to
9 and a display 10 are provided. A release button 7 is an operation
member having first- and second-stroke depression conditions. With
the first-stroke depression (half depression) of the release button
7, shooting preparations such as distance measurement are performed,
and with the second-stroke depression (full depression), recording
(shooting) is performed. A mode switch 8 is a slide operation member
used for switching the operation mode among an "OFF mode",
a "recording (shooting) mode" and a "reproduction
mode". A self-timer shooting setting switch 9 for setting the
shooting mode of the camera is used for switching between a "normal
shooting mode" and a "self-timer shooting mode".
In the present invention, the normal shooting mode is a mode in
which shooting is performed immediately after an instruction to
start shooting is provided and processing necessary for shooting
is performed. The self-timer shooting mode is a mode in which shooting
is performed after a time which is the sum of a predetermined time
and the time from the instruction of shooting to shooting in the
normal shooting mode has elapsed. Detailed operations of the operation
members 7 to 9 will be described later. The display 10 comprising
an LCD or the like is for displaying shooting data, setting of self-timer
shooting, the frame number in shooting and other contents of the
set mode.
FIG. 2 is a schematic perspective view of the digital camera according
to the present invention obliquely looked down on from the rear.
As shown in FIG. 2, a memory card slot 12 is provided on a side
surface of the camera body 1. The memory card slot 12 has a slit
form and is provided for inserting a memory card serving as an external
recording medium into the camera body 1. On the back surface of
the camera body 1, an image display LCD 13 is provided. Since the
image display LCD 13 is thin and lightweight, the carryability of
the camera is not impaired. Because of the image display LCD 13,
in the recording (shooting) mode, the photographer can confirm the
image to be shot without viewing through the finder window. Therefore,
the subject can be shot at an extremely free angle. Moreover, since
the shot image is displayed on the image display LCD 13 after shooting
until a predetermined time has elapsed, the photographer can check
whether the shot image is desired or not without performing any
complicated operations. In the reproduction mode, the recorded images
can be selectively displayed on the image display LCD 13. Since
an optical finder and a finder window 14 for viewing are provided
besides the image display LCD 13, when the image display LCD 13
is in a non-displaying state (off), the photographer can perform
shooting while viewing through the finder window 14. Because of
this structure, battery drain can be restrained by cutting off the
power consumed by the image display LCD 13, so that the camera can
be driven for a longer time.
On the back surface of the camera body 1, operation buttons 15
and 16 are provided. The operation buttons 15 and 16 have different
functions according to the operation mode of the camera. That is,
in the recording (shooting) mode, the operation buttons 15 and 16
function as zoom buttons for adjusting the shooting field. The taking
lens 2 is zoom-driven toward the wide-angle side when the operation
button 15 is depressed, and is zoom-driven toward the telephoto
side when the operation button 16 is depressed. In the reproduction
mode, the operation buttons 15 and 16 function as access buttons
for calling up recorded images. When the operation button 15 is
depressed, recorded images to be displayed on the image display
LCD 13 are called up in forward order, and when the operation button
16 is depressed, recorded images are called up in inverse order.
In addition to the above-described members, an in-focus display
lamp 17 is provided on the back surface of the camera body 1. When
the release button 7 is first-stroke-depressed (half depressed),
the in-focus display lamp 17 is turned on in a case where the shooting
preparations are normally finished, and blinks in a case where the
shooting preparations are not normally finished. Because of this
structure, when the in-focus display lamp 17 is blinking, the photographer
can be informed that shooting is impossible, for example, because
the distance to the subject is too short or the flash is being charged.
Next, the internal structure and operation of the digital camera
according to the present invention will be described with reference
to FIG. 3. FIG. 3 is a block diagram showing the general structure
of the digital camera according to the present invention. The operation
of the digital camera according to the present invention is controlled
by a system controller 100 having a central processing unit (CPU)
(hereinafter, referred to as CPU 100) and a program in a read only
memory (ROM) 112 connected to the CPU 100. To perform image capture,
a subject image formed through the taking lens 2 is captured by
a solid-state image sensing device 101 (hereinafter, referred to
as CCD 101) and image processing is performed on the output signal
from the CCD 101 at a signal processing portion 102. In image capture,
a lens driving portion 103 drives the taking lens 2 so as to be
in an in-focus state. The drive amount of the taking lens 2 is a
value calculated by the CPU 100 based on distance measurement data
obtained by a distance measurement portion 104. The distance measurement
portion 104 finds the focus condition, for example, by the phase
difference detection method. A photometric measurement portion 105
supplies the CPU 100 with photometric data obtained by measuring
the subject brightness.
The CPU 100 calculates the shutter speed Tv and the aperture value
Av based on the data input from the distance measurement portion
104 and the photometric measurement portion 105, and outputs the
calculated values to an exposure control portion 106. The exposure
control portion 106 controls exposure based on the data Tv and Av.
A display portion 107 comprises the display 10, the image display
LCD 13 and portions for driving them. The image and various pieces
of information obtained through the above-described operations are
output by the display portion 107.
A power source portion 108 supplies a predetermined high voltage
to the CCD 101, and a voltage of a predetermined level to other
circuit portions. A flash portion 109 causes the flash 6 to emit
light based on a voltage increase control signal for charging and
a light emission control signal output from the CPU 100. A recording
portion 110 is a data recording portion permanently provided in
the camera body 1. In the recording portion 110, shooting data having
undergone predetermined image processing at the signal processing
portion 102 in shooting is recorded. The recording portion 110 may
be used as a buffer memory for a memory card 111 attachable to the
camera body 1, or may be used as a main memory for image recording
because the recording portion 110 has a certain amount of storage
capacity. The memory card 111 is a recording medium comprising a
static random access memory (SRAM) or the like on which a plurality
of images can be recorded. To move shooting data to a personal computer
or the like, first, the shooting data is transferred to the memory
card 111, and then, the shooting data recorded on the memory card
111 is read out on the side of the personal computer.
Next, switches S.sub.OFF to S.sub.self will be described. Of switches
S.sub.OFF, S.sub.REC and S.sub.REP, only the one selected by the
mode switch 8 is on and the other switches are off. The switch S.sub.OFF
is on when the mode switch 8 is in the "OFF" position,
so that the camera is deactivated. At this time, the lens driving
portion 103 causes the lens barrel 3 to collapse and closes the
lens barrier 11. The switch S.sub.REC is on when the mode switch
8 is in the "recording (shooting)" position, so that the
camera is in a shooting possible state. At this time, the lens driving
portion 103 opens the lens barrier 11 and causes the lens barrel
3 to protrude. The switch S.sub.REP is on when the mode switch 8
is in the "reproduction" position. At this time, the access
to the recording portion 110 and the memory card 111 is permitted,
so that the camera is in a state in which data transfer to a personal
computer or the like is possible.
Switches S.sub.1 and S.sub.2 are activated by operating the release
switch 7. With the first-stroke depression (half depression) of
the release switch 7, the switch S.sub.1 is turned on, so that the
CPU 100 instructs the circuit portions to perform shooting preparations
such as distance measurement. With the second-stroke depression
(full depression) of the release switch 7, the switch S2 is turned
on, so that the CPU 100 instructs the circuit portions to shooting
operations such as exposure. Details of the release sequence will
be described later. Switches S.sub.up and S.sub.down are switches
for accessing recorded images, and are activated by depressing the
operation buttons 15 and 16 in the reproduction mode. Every time
the operation button 15 is depressed, the switch S.sub.up is turned
on, so that recorded images are displayed on the image display LCD
13 one by one in forward order. On the other hand, every time the
operation button 16 is depressed, the switch S.sub.down is turned
on, so that recorded images are displayed on the image display LCD
13 one by one in inverse order.
A switch S.sub.CARD is a memory card recognition switch which is
on when the memory card 111 is inserted in the camera body 1. A
switch S.sub.self is alternately turned on and off every time the
self-timer shooting setting switch 9 is depressed. When the switch
S.sub.self is on, the camera is in the "self-timer shooting
mode", and when the switch S.sub.self is off, the camera is
in the "normal shooting mode". The "self-timer shooting
mode" is a shooting mode in which shooting is on standby for
a first predetermined time t1 (hereinafter, sometimes referred to
as self time) after the release button 7 is second-stroke-depressed
(fully depressed) and shooting is performed after the first predetermined
time t1 has elapsed. Because of this function, the photographer
himself or herself can be the subject. In the "normal shooting
mode", shooting is performed immediately after the release
button 7 is second-stroke-depressed (fully depressed).
Next, the release sequence in a first embodiment of the digital
camera according to the present invention will be described with
reference to FIG. 4. FIG. 4 is a flowchart showing the release sequence
in the first embodiment. In this embodiment, the time for which
the shot image is displayed after shooting in the "self-timer
shooting mode" is longer than that in the "normal shooting
mode". This image display control is performed by the CPU 100
as mentioned above.
First, at step #100, whether an instruction to start shooting is
provided or not (whether the switch S2 is on or off) is determined.
When an instruction to start shooting is provided, whether the camera
is in the self-timer shooting mode or not (whether the switch S.sub.self
is on or off) is determined at step #110. When the camera is not
in the self-timer shooting mode, that is, when the switch S.sub.self
is off, it is determined that the camera is in the "normal
shooting mode", and the process moves to step #170 to perform
shooting immediately after an instruction to start shooting is provided.
In shooting, the lens driving portion 103 drives the lens based
on the data obtained by the distance measurement portion 104, and
the exposure control portion 106 controls exposure based on the
data obtained by the photometric measurement portion 105. When necessary,
the flash portion 109 causes the flash 6 to emit light. After shooting
is finished, at step #180, the shot image is displayed on the image
display LCD 13. At step #190, the display of the shot image on the
image display LCD 13 is continued until a shot image display time
(second predetermined time t2) has elapsed. Because of this, the
photographer can check the image having just been shot. After the
second predetermined time t2 has elapsed, the process moves to step
#200 to end the display of the shot image. With this, shooting of
one frame in the "normal shooting mode" is finished, and
the sequence ends.
When it is determined at step #110 that the camera is in the "self-timer
shooting mode", that is, when the switch S.sub.self is on,
the process moves to step #120 so that shooting is on standby for
the first predetermined time t1 (for example, 10 seconds). After
the first predetermined time t1 has elapsed, the process moves to
step #130 to perform shooting like at step #170. After shooting
is finished, at step #140, the shot image is displayed on the image
display LCD 13. At step #150, the display of the shot image on the
image display LCD 13 is continued until a shot image display time
(third predetermined time t3) has elapsed. Here, the third predetermined
time t3 is longer than the shot image display time (second predetermined
time t2) in the "normal shooting mode". For example, when
the second predetermined time t2 is two seconds, the third predetermined
time t3 is, for example, 15 seconds. Because of this, it does not
occur that the display of the shot image ends before the photographer
who is the subject returns to the camera. Therefore, the photographer
can check the image having just been shot, without performing any
complicated operations.
By setting the shot image display time (third predetermined time
t3) so as to be also longer (15 seconds) than the self time (first
predetermined time t1, 10 seconds) like in this embodiment, it is
unnecessary for the photographer to flurry when returning to the
camera after shooting. The third predetermined time t3 may be set
by the photographer. In this case, after shooting, the photographer
returns to the camera within the time set by the photographer. Since
the photographer knows the time for which the display of the shot
image is continued, the photographer can return to the camera without
flurrying. After the third predetermined time t3 has elapsed, the
process moves to step #160 to end the display of the shot image.
With this, shooting of one frame in the "self-timer shooting
mode" is finished, and the sequence ends.
Next, the release sequence in a second embodiment of the digital
camera according to the present invention will be described with
reference to FIGS. 5 and 6. FIG. 5 is a flowchart showing the release
sequence in the second embodiment. In this embodiment, the self
time (first predetermined time t1) in the "self-timer shooting
mode" can be changed between two values, and in accordance
with the change, the time (third predetermined time t3) for which
the shot image is displayed after shooting is changed. Further,
in this embodiment, means is provided for discontinuing the display
of the shot image before the third predetermined time t3 has elapsed.
Except these, the second embodiment is similar to the first embodiment.
In the release sequence shown below, only the parts different from
those of the first embodiment will be described.
The first difference is that after it is determined at step #220
that the camera is in the "self-timer shooting mode",
a self time confirmation sequence is performed at step #230. FIG.
6 is a flowchart of the self time confirmation sequence. In this
embodiment, two different values a and b (for example, a is 10 seconds
and b is 15 seconds, and a<b) are provided as candidates of the
set value of the self time (first predetermined time t1) that can
be set by the photographer. In the self time confirmation sequence,
whether the set value of the first predetermined time t1 is a or
not is determined at step #340. When the set value is a, the process
moves to step #350 to set a as the first predetermined time t1.
Then, a' is set as the third predetermined time t3 at step #360,
and the sequence returns. When it is determined at step #340 that
the set value of the first predetermined time t1 is not a, the process
moves to step #370 to set b as the first predetermined time t1.
Then, at step #380, b' is set as the third predetermined time t3,
and the sequence returns.
Here, the values of a' and b' are, for example, 15 seconds and
20 seconds which are five seconds longer than the values of a and
b (a'<b'). That is, when a is set as the self time (first predetermined
time t1), it is considered that the distance between the camera
and the photographer who is the subject is comparatively short.
Therefore, in this case, the comparatively short time a' is set
as the shot image display time (third predetermined time t3). When
b is set as the first predetermined time t1, since the probability
that the photographer is at a distance from the camera is high,
it is necessary that the long time b' is set as the third predetermined
time t3. Because of this structure, only by setting the self time
(first predetermined time t1), the shot image display time (third
predetermined time t3) suitable for the set self time is automatically
set, which is very convenient.
While the self time (first predetermined time t1) can be changed
between two values in this embodiment, it may be changeable among
more than two values. In that case, combinations of the self time
(first predetermined time t1) and the shot image display time (third
predetermined time t3) may be stored in a ROM, or a function may
be set to calculate t3 from t1.
Reverting to the release sequence of FIG. 5, the second difference
will be described. After returning from the self time confirmation
sequence, the process moves to step #240 so that shooting is on
standby for the self time (predetermined time t1) set in the self
time confirmation sequence. Then, shooting is performed at step
#250. After shooting is finished, at step #260, the shot image is
displayed on the image display LCD 13. In this embodiment, at step
#270, whether the self-timer shooting setting switch 9 is depressed
or not is determined. When it is determined that the self-timer
shooting setting switch 9 is depressed, the process moves to step
#290 to end the display of the shot image, and the sequence returns.
The above-described structure is provided as the means for discontinuing
the display of the shot image even before the shot image display
time (third predetermined time t3) has elapsed when the photographer
intends to do so. Because of this structure, after the photographer
who is the subject returns to the camera and checks the shot image,
the photographer can move to the next shooting without waiting until
the third predetermined time t3 has elapsed. Thus, the camera provides
excellent usability. By using the self-timer shooting setting switch
9 also as the means for discontinuing the display of the shot image
like in this embodiment, it is unnecessary to provide a new operation
member, and the operation is easy because it can be performed with
a single switch depression.
In the digital camera according to the present invention, the time
(third predetermined time t3) for which the shot image is displayed
after shooting in the "self-timer shooting mode" is longer
than the shot image display time (second predetermined time t2)
in the "normal shooting mode". Because of this, it does
not occur that the display of the shot image ends before the photographer
who is the subject returns to the camera. Therefore, the photographer
can check the image having just been shot, without performing any
complicated operations. Since the shot image display time (third
predetermined time t3) is longer than the self time (first predetermined
time t1) in the "self-timer shooting mode", it is unnecessary
for the photographer to flurry when returning to the camera after
shooting.
While the self-timer shooting in which shooting is performed after
several seconds have elapsed has been described in the embodiments,
the present invention is applicable to so-called interval shooting
in which shooting is performed after several minutes or several
hours have elapsed.
Although the present invention has been fully described by way
of examples with reference to the accompanying drawings, it is to
be noted that various changes and modifications will be apparent
to those skilled in the art. Therefore, unless otherwise such changes
and modifications depart from the scope of the present invention,
they should be construed as being included therein.
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