(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2006/0055814 A1
`
`
` Okawa et al. (43) Pub. Date: Mar. 16, 2006
`
`US 20060055814A1
`
`(54)
`
`IMAGE PICKUP DEVICE AND FOCUSING
`NOTIFICATION METHOD
`
`(30)
`
`Foreign Application Priority Data
`
`(75)
`
`Inventors: Akira Okawa, Yokohama (JP); Ryo
`Suzuki, Yokohama (JP); Noriyuki
`Uenlshl, Kawasaki (JP)
`
`Correspondence Address:
`ARENT FOX PLLC
`1050 CONNECTICUT AVENUE, N.W.
`SUITE 400
`WASHINGTON, DC 20036 (US)
`
`(73) Assignee: FUJITSU LIMITED
`
`(21) Appl. No.:
`
`11/050,748
`
`(22)
`
`Filed:
`
`Feb. 7, 2005
`
`Sep. 16, 2004
`
`(JP) ...................................... 2004-269382
`
`Publication ClaSSIficatlon
`
`(51)
`
`Int. Cl.
`(2006.01)
`H04N 5/232
`(2006.01)
`H04N 5/222
`(52) US Cl.
`...................................... 348/346, 348/333.02
`(57)
`ABSTRACT
`To inform the users of the time necessary for focus to be
`achieved by changing the focal mark shown on the display
`monitor, second by second, corresponding to the elapsed
`time from the start of the auto focus operation until focus is
`achieved. The users are informed of the status of the auto
`focusing operations, and have a good idea of how much
`longer it will take for focusing to be completed. As a result,
`it increases the probability of users holding the camera still,
`so as to produce precisely focused photographs.
`
`AUTOFOCUSING IN
`
`COMPLETION OF
`
`PROGRESS
`
`FOCUSING
`
`
`
`FOCAL MARK 30 (RED)
`DISPLAY UNIT 20
`
`FOCAL MARK 30
`(GREEN)
`
`1
`
`APPLE 1006
`
`APPLE 1006
`
`1
`
`

`

`Patent Application Publication Mar. 16, 2006 Sheet 1 0f 6
`
`US 2006/0055814 A1
`
`FIG. 1
`
`AUTOFOCUSING IN
`
`COMPLETION OF
`
`PROGRESS
`
`FOCUSING
`
`
`
`FOCAL MARK 30
`
`FOCAL MARK 30
`
`DISPLAY UNIT 20
`
`2
`
`

`

`Patent Application Publication Mar. 16, 2006 Sheet 2 0f 6
`
`US 2006/0055814 A1
`
`FIG. 2A
`
`AUTOFOCUSING IN
`
`COMPLETION OF
`
`PROGRESS
`
`FOCUSINC
`
`
`
`FOCAL MARK 30 (RED)
`DISPLAY UNIT 20
`
`FOCAL MARK 30
`(GREEN)
`
`FIG. 28
`
`AUTOFOCUSING IN
`
`COMPLETION OF
`
`PROGRESS
`
`FOCUSING
`
`
`
`FOCAL MARK 30 (RED)
`DISPLAY UNIT 20
`
`FOCAL MARK 30
`(GREEN)
`
`3
`
`

`

`Patent Application Publication Mar. 16, 2006 Sheet 3 0f 6
`
`US 2006/0055814 A1
`
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`Patent Application Publication Mar. 16, 2006 Sheet 4 0f 6
`
`US 2006/0055814 A1
`
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`Patent Application Publication Mar. 16, 2006 Sheet 5 0f 6
`
`US 2006/0055814 A1
`
`FIG. 5A
`
`FIG. 5D
`
`FOCAL MARK 3O
`
`FOCAL MARK 30
`
`FIG. 5E FOCAL MARK 30
`
`FIG. 5B FOCAL MARK 3
`
`
`
`
`6
`
`

`

`Patent Application Publication Mar. 16, 2006 Sheet 6 0f 6
`
`US 2006/0055814 A1
`
`FIG- 6
`
`m REQUEST FOR AF?
`
`SI
`
`Y
`
`OBTAINING PICTURE TAKING MODE
`
`$2
`
`DRIVING LENS
`
`DISPLAYING FOCAL MARK ACCORDING TO 34
`AN ELAPSED TIME OF AF OPERATION
`
`S3
`
`
`
`
`
`OBTAINING CONTRAST DATA
`
`PROCESSING AF DATA
`
`S5
`
`86
`
`COMPLETION OF
`AF OPERATION?
`
`S7
`
`Y
`
`MOVING LENS TO FOCAL POSITION
`
`$8
`
`DISPLAYING FOCAL MARK INDICATING
`COMPLETION OF FOCUSING
`
`$9
`
`REQUEST FOR
`PICTURE TAKING?
`
`Y
`
`S10
`
`FOCAL MARK DISAPPEARED
`
`311
`
`I
`
`PICTURE TAKING PROCESSING
`
`I 312
`
`END
`
`7
`
`

`

`US 2006/0055814 A1
`
`Mar. 16, 2006
`
`IMAGE PICKUP DEVICE AND FOCUSING
`NOTIFICATION METHOD
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`[0001] This application is based upon and claims priority
`of Japanese Patent Application No. 2004-269382, filed in
`Sep. 16, 2004, the contents being incorporated herein by
`reference.
`
`BACKGROUND OF THE INVENTION
`
`[0002]
`
`1. Field of the Invention
`
`[0003] This invention relates to an image pickup device,
`such as digital cameras equipped with an auto focus function
`(including digital cameras built into cell phones), etc. and, in
`particular, relates to an image pickup device and focusing
`notification method to provide notification about elapsed
`time from the start of the auto focus operation until focus is
`achieved.
`
`[0004]
`
`2. Description of the Related Art
`
`[0005] On digital cameras which have been coming into
`wide use rapidly in recent years, the high resolution and
`functionality have been advancing, and the built-in auto
`focus function with which cameras automatically focus is
`becoming common.
`
`[0006] FIG. 1 shows an example of existing focusing
`notification methods. In FIG. 1, on display unit 20, such as
`the finder of an image pickup device or the liquid crystal
`display (LCD), the monitor displays the focal state, in other
`words, focal mark 30 is displayed to show that the auto focus
`is in progress or the completion of focusing along with the
`subject. In the example of FIG. 1, focal mark 30 is displayed
`during auto focusing as a rectangular frame, and is displayed
`as a cross after focusing. In this way, by differentiating
`between auto focus in progress and completion of focusing,
`users are notified about the completion of focusing. This
`allows users to judge when to press the shutter button for
`image pickup.
`
`[0007] FIGS. 2A and 2B show other examples of the
`existing focusing notification methods. In another example,
`focal mark 30 does not take different forms between auto
`
`focus in progress and focusing in progress, but there are
`differences in color (for example, from red to green) and
`users are notified that focusing has been completed. In
`FIGS. 2A and 2B, the forms of the focal mark and the
`display positions are different.
`
`[0008] Also, on auto focus cameras, a scale is inserted
`around subjects to clarify the size of subjects, and image
`pickup devices are also known that insert a scale, with its
`index automatically adjusted, depending on the distance to
`the subjects, as measured by the auto focus operation.
`
`[0009] Generally, it is desirable to immobilize a camera
`during the auto focus operation because this helps to mea-
`sure the focal distance more accurately. On the other hand,
`a slight movement of the hands holding a camera prevents
`the accurate measurement of focal distance. The auto focus
`
`function needs to operate a lens, and also, when trying to
`enhance accuracy, more time is required. Users tend to be
`concerned about the time to achieve focus. During the time
`
`to achieve focus, it may happen that accurate focus is not
`obtained, due to movement of the hands.
`
`[0010] Meanwhile, as prior art, during the time from the
`start of the auto focus operation until focus is achieved, if the
`mark showing the auto focusing is constantly displayed,
`users cannot judge how much time remains before focus is
`achieved. For this reason, during auto focusing, the prob-
`ability of causing hand movement may be increased, and the
`problem is that focal distance cannot be measured accu-
`rately.
`
`[0011] Under these circumstances, a means is needed for
`visually notifying users of the time for focus to be achieved.
`
`SUMMARY OF THE INVENTION
`
`[0012] Consequently, the objective of this invention is to
`offer an image pickup device and focusing notification
`method which can notify users of the time until focus is
`achieved by continuously changing the focal mark on the
`display monitor, second by second, during the time from the
`start of auto focus operation until focus is achieved, depend-
`ing on the elapsed time.
`
`[0013] The first structure of the image pickup device in
`this invention to achieve the abovementioned objective is
`characterized by comprising: a display for displaying pic-
`tures taken in from a lens; and a control unit for controlling
`to display a focal mark showing the focal condition on said
`display unit and changing the focal mark according to an
`elapsed time from the start of the auto focus operation until
`focus is achieved.
`
`the second structure of the image pickup
`[0014] Also,
`device in this invention is characterized in that, in the above
`first structure, said control unit changes the form, color or
`display position of said focal mark.
`
`[0015] Also, the third structure of the image pickup device
`in this invention is characterized in that, in the above first
`structure, an auto focus operation determines a focal location
`by driving the lens in sequence to multiple locations con-
`figured in advance, and wherein the control unit changes the
`focal mark according to driving of the lens to each location.
`
`the fourth structure of the image pickup
`[0016] Also,
`device in this invention is characterized in that, in the above
`first structure, during the focal mark is being changed based
`on a first elapsed time that was planned, from the start of the
`auto focus operation until focus is achieved, when a remain-
`ing time of the first elapsed time until focus is achieved
`changes due to the progress of the auto focus operation, the
`control unit updates of changes in the focal mark according
`to changes in the remaining time.
`
`[0017] Also, a method for providing notification about the
`focusing time in an auto focus operation in this invention is
`characterized by comprising the steps of: displaying a focal
`mark showing the focal state, when displaying images taken
`in from a lens; and changing the focal mark according to an
`elapsed time from the start of the auto focus operation until
`focus is achieved.
`
`[0018] The image pickup device and focusing notification
`method in this invention allow users to show the progress of
`the auto focus operation by means of changing the focal
`mark, depending on the elapsed time from the start of the
`auto focus operation until focus is achieved.
`
`8
`
`

`

`US 2006/0055814 A1
`
`Mar. 16, 2006
`
`In the event that the auto focus operation takes
`[0019]
`longer than users expect, it would likely cause the users to
`move their hands, which are holding the camera, during auto
`focusing, but as a result of this invention, users know the
`progress of the auto focus operation, and can judge how
`much more time will elapse before focus is achieved, so the
`probability of the movement of hands is decreased, and
`focus can be accurately achieved.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0020] FIG. 1 is a figure of a conventional focusing
`notification method.
`
`[0021] FIGS. 2A and 2B are figures of another conven-
`tional focusing notification method.
`
`[0022] FIG. 3 is a figure of an example of the block
`structure of an image pickup device in the form of execution
`of this invention.
`
`[0023] FIG. 4 is a figure to describe the auto focus
`operation in the normal mode.
`
`[0024] FIGS. 5A-5F are figures to describe the changes in
`the focal mark in the form of execution of this invention.
`
`[0025] FIG. 6 is a flow chart showing auto focusing
`operation in progress in the form of execution of this
`invention.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`[0026] The form of execution of this invention will now be
`explained, referring to the figures. However, these examples
`of the forms of execution do not limit the technical scope of
`this invention.
`
`[0027] FIG. 3 shows examples of the block structure of an
`image pickup device in the form of execution of this
`invention. In image pickup device 1, lens 10 takes the light
`of the subject into the image pickup device 1, collects all the
`light and then transmits it to sensor 12. Sensor 12, which
`consists, for example, of a CCD or C-MOS sensor, etc.,
`takes the light collected at lens 10, and by sorting the colors
`(the three primary colors), sends out color signals to a later
`stage, the signal processing unit 16. An auto focus driving
`unit 14 drives lens 10 using a stepping motor, etc., changes
`the distance from sensor 12, and changes the distance from
`the subject in order for focus to be achieved (focusing).
`Signal processing unit 16 processes the production of data
`that is to be displayed, by transforming color signals sent by
`sensor 12 into a data format which can be displayed on
`display unit 20, and various other signal processing such as
`the processing of the results of detection arising from auto
`focus operations. Control unit 18 controls to display the
`display data acquired from signal processing unit 16, on
`display unit 20, and additionally controls signal processing
`unit 16 and auto focus driving unit 14 when operation unit
`18 requests auto focus operations from operation unit 22.
`Display unit 20 displays the display data sent by control unit
`18. Operation unit 22 includes a power switch and shutter,
`etc., for example, and by pressing the shutter halfway down,
`the requirement for auto focus is output, and also by pressing
`the shutter all the way down, the requirement for taking a
`picture is output.
`
`In image pickup device 1 of the above structure,
`[0028]
`with the present example of the forms of execution, during
`the time from the start of the auto focus operation until focus
`is achieved, the focal mark displayed on display unit 20 is
`changed according to the elapsed time.
`In the form of
`execution of this invention, without regard to the type of
`auto focus, any type of auto focus function can be applied.
`An example is now described which adopts a focusing
`method in which, in cases where an image pickup device
`drives a lens with a stepping motor, graphic contrast is
`transformed in each of multiple sample steps placed in a
`pre-set specific step interval out of the total number of steps,
`and a lens is driven to the location of the sample step with
`the maximum peak.
`
`the image pickup device may have two
`[0029] Also,
`modes, the normal mode and the macro mode, for picture
`taking. The normal mode is used when the focal distance
`ranges from infinitely far to about 30 cm, and macro mode
`is used when the focal distance is no more than 30 cm and
`
`no less than 5 cm. Due to the properties of the lens, the
`shorter the focal distance is, the shallower the depth of field
`becomes, and the narrower the width of the focus distance
`to be achieved becomes. Therefore, when using the macro
`mode, compared to the normal mode, the step interval is
`required to be smaller or the number of samples in the
`sample step needs to be increased. For example, there are 5
`samples in the normal mode and 10 samples in the macro
`mode. Imaging mode can be optionally switched through the
`operation, by the user, of operation unit 22. Of course, an
`image pickup device without multiple imaging modes, can
`be a structure to move seamlessly from the nearest point to
`an infinite point, but in the example of the forms of execu-
`tion below, a case with the 2 abovementioned imaging
`modes is explained.
`
`[0030] FIG. 4 describes the auto focus operations in the
`normal mode. In the normal mode, the 5 sample steps to
`cover the focal distance in the area of infinitely-far to 30 cm
`are pre-set. When the auto focus function is requested, signal
`processing unit 16 operates the lens in sequence to each
`sample step at each one-frame rate (e.g. 100 m/s) which is
`a unit of processing, takes in the graphic contrast data on the
`spot, decides the contrast at the fifth and final frame rate, and
`drives the lens to the sample step position with the maximum
`peak (the focal position). This is how focus is achieved. In
`this case, it takes half a second (5x100 ms=500 ms) from the
`start of the auto focus operation until focus is achieved.
`
`the focal mark shown on display unit 20
`[0031] Thus,
`keeps changing second by second, in response to the opera-
`tion of a lens in the middle of auto focusing, as focus is
`achieved simply by operating a lens according to the number
`of samples per frame rate and finally it displays the specific
`focal mark indicating that achievement of focus has been
`attained.
`
`[0032] FIGS. 5A-5F describe the changes of the focal
`mark in the form of execution in this invention. FIGS.
`
`5A-5F correspond to time Ato F in FIG. 4, respectively. The
`focal mark 30 in the midst of auto focusing is displayed as
`a rectangular frame and its size gets smaller with elapsed
`time (every time a lens moves to a sample step position), as
`shown in FIGS. 5A-5F and is displayed as a cross (FIG. 5F)
`which informs the users of completion of focusing once
`focusing is attained.
`
`9
`
`

`

`US 2006/0055814 A1
`
`Mar. 16, 2006
`
`[0033] As stated above, in the event that a lens operates
`per frame rate on the normal mode the display of the focal
`mark changes per one-frame rate. If a subject is placed in a
`dark area where there is not enough light for sensor 12 to
`obtain contrast data in an exposure at the one-frame rate, a
`lens operates in the frame rate interval in correspondence
`with the time necessary to obtain a sufficient amount of light,
`and also the focal mark changes in that particular frame rate
`interval. For example, the focal mark 30 keeps changing for
`each two-frame rate if an exposure at one sample step and
`AF processing (accumulation of contrast data at each sample
`step and decision of contrast at
`the final sample step)
`requires time covering the two-frame rate. The amount of
`time necessary from the start of the auto focus operation
`until focus is achieved in this example is one second
`(5x2x100 ms=1 s). That translates into slower changes of the
`focal mark.
`
`In the macro mode, as stated earlier, the number of
`[0034]
`sample steps is greater than in the normal mode. If there are
`10 sample steps, a lens needs to be operated ten times in
`order to achieve focus. In the event that a lens operates every
`one-frame rate, it takes one second (10x100 ms=1 s) from
`the start of the auto focus operation until focus is achieved.
`Also, in this case, the display of the focal mark changes 10
`times in response to a lens operation. As in the example
`shown in FIGS. 5A-5F, the size of the focal mark frame gets
`smaller in the middle of auto focusing and it turns into a
`cross sign once focus is achieved. If the size of the focal
`mark at the default setting is the same for both normal mode
`and macro mode, the rate of decrease in the size of the focal
`mark on the macro mode needs to be slower considering the
`fact that the focal mark changes twice as often in the macro
`mode as it does in the normal mode in the above example.
`
`In control unit 18, for example, the data of a group
`[0035]
`of 10 focal marks, consisting of rectangular focal marks and
`cross-shaped signs, with sizes that gradually become mini-
`mized, are stored in advance.
`In the macro mode, 10
`rectangular signs are shown in sequence starting with the
`largest one and the cross-shaped focal mark is shown once
`focus is achieved. In the normal mode, every other rectan-
`gular sign is shown, starting with the largest one, since the
`number of changes is half as many as is the case with the
`macro mode. The cross-shaped focal mark is shown once
`focus is achieved. By having a group of focal marks for
`macro mode, it is ready to be applied to the normal mode as
`well. Of course, it is also possible to have a group of focal
`marks exclusively for the normal mode.
`
`In the normal mode, in which a lens operates every
`[0036]
`two-frame rate, the focal mark could change 5 times every
`two-frame rate with which a lens operates or it could change
`10 times every one-frame rate. Either way, the velocity of
`change in size of the focal mark is the same.
`
`If there is not enough light for sensor 12 to obtain
`[0037]
`the contrast data in an exposure within one—frame rate
`because of a subject placed in a dark area when operating in
`the macro mode, a lens needs to operate in the interval in
`correspondence with the time necessary to obtain enough
`light, as was the case in the abovementioned normal mode,
`and the focal mark also changes in that frame rate interval.
`If time covering the two-frame rate is required for the
`exposure at one sample step and AF processing, focal mark
`30 keeps changing every two-frame rates. The amount of
`
`time from the start of the auto focus operation until focus is
`achieved in this case is 2 seconds (10x2x100 ms=2 s).
`Therefore, the velocity of change in the focal mark is slower.
`
`[0038] Thus, the size of and velocity of changes in the
`focal mark give the users a good idea of how much longer
`it will take for focus to be achieved by changing the focal
`mark according to the status of the auto focus operations.
`Also, they provide users with the assurance that auto focus-
`ing is under way.
`
`In the form of execution described in the above
`[0039]
`example, the descriptions of how the shape of focal mark
`can change were given. However, changes in the focal mark
`are not limited to shape. For example, the color or display
`position can also be changed. In the case where the display
`position changes, the distance between the position at the
`start of auto focusing to that at completion is always
`constant, and the users can tell how much longer it takes for
`focus to be achieved by the display position of the focal
`mark, as well as the velocity of changes. In the case where
`the color of the mark changes, the change pattern of the focal
`mark color is always constant from the start of auto focus
`operations to the completion of focusing. That way, if the
`velocity of color changes in the focal marks changes, the
`users can tell how much longer it will take for focus to be
`achieved, by the color and rate of change in color.
`
`[0040] Also, the shape of the focal mark is not limited to
`the rectangular frame displayed in the form of execution in
`the above example. It could be any kind of shape as long as
`the users can recognize the development in the status of auto
`focusing. For example, a focal mark in a circle can work if
`it gets smaller as the auto focusing operation progresses.
`
`[0041] FIG. 6 shows a process flow chart in the form of
`execution of this invention. This process is the one operated
`in control unit 18, which controls signal processing unit 16,
`auto focus driving unit 14 and display unit 20 according to
`this process flow. In step SI, when there is a request for auto
`focusing (AF) operation, typically by pressing the shutter
`halfway down, picture-taking mode (normal mode or macro
`mode) is prepared (S2). In this form of execution, picture-
`taking mode needs to be prepared, and this is exemplified by
`the case in which, because of picture taking mode,
`the
`number of lens operations in the middle of auto focusing is
`different in each case. If there is no picture taking mode, this
`process is not necessary.
`
`In the next step, a lens is operated (S3) at the
`[0042]
`position of the first sample step corresponding to the pre-set
`picture-taking mode. In step S4,
`the first focal mark is
`indicated (for example,
`the focal mark in FIG. 5A). In
`addition, the graphic contrast data obtained (SS) by sensor
`12 is stored after being processed as auto focus data in step
`S6. In step S7,
`the processes in step S3 to step S6 are
`repeated if a lens is not driven at each one of sample steps.
`In other words, a lens is driven at the next sample step, the
`focal mark changes in sequence, and the graphic contrast
`data at a particular sample step are obtained and stored.
`
`[0043] Once the contrast data at all of sample steps is
`obtained, and furthermore, as the auto focusing data process
`in step S6, the graphic contrast of the image is decided for
`the lens focus position to be determined where the lens is
`moved (SS). When a lens is driven to the focal position, the
`focal mark to indicate completion of focusing is displayed
`
`10
`
`10
`
`

`

`US 2006/0055814 A1
`
`Mar. 16, 2006
`
`(S9). When there is a request for picture taking (810), by
`means of the shutter being pressed all the way down, the
`focal mark disappears ($11) and the picture taking process-
`ing is conducted ($12).
`
`the process in
`In the above form of execution,
`[0044]
`which the focal mark in the middle of auto focusing changes
`corresponding to a lens operation in the middle of auto
`focusing is described. There is another way of processing.
`First,
`the time necessary for focusing is calculated (an
`example of this calculation was shown earlier) based on
`exposure time (the time necessary to obtain enough light for
`the purposes of contrast data acquisition), which is obtained
`through information about the graphic brightness and the
`number of sample steps to be obtained through picture
`taking mode. The calculated time is divided by certain
`number (e. g. 5 times or 10 times in earlier examples) to yield
`the number of changes of the focal mark in this process. In
`step 2 of FIG. 6, information about the graphic brightness in
`addition to the picture-taking mode is obtained. The calcu-
`lation to determine time necessary to achieve focus varies,
`depending on the type of auto focus function. The appro-
`priate calculation for each function needs to be performed.
`
`In the above form of execution, an auto focus
`[0045]
`operation is described,
`in which a lens operates at
`the
`position of sample steps, of which the number is pre-
`determined. This form of execution can also be applied to
`other types of auto focus operations. For example, in the
`case where contrast is decided based on the contrast data
`
`stored at each sample step, the focal position can sometimes
`be determined prior to acquisition of contrast data at all of
`the sample steps, by recognizing the end of the peak. Thus,
`if the remaining time to achieve focus changes in response
`to the progress of the auto focus operations, the changes in
`the focal mark can be updated by changing the velocity of
`changes in the focal mark, in response to the changes in the
`remaining time to achieve focus, without having to keep
`changing the focal mark all the time, and by leaving out
`some of the in-between focal marks, when the focal position
`is determined to change the shape of the current focal mark
`to the one prior to the completion of focus.
`
`In the case where auto focusing is performed by
`[0046]
`measuring distances using electromagnetic waves such as
`infrared, the focal mark should be designed to change in
`sequence for the entire time during the pre-set amount of
`time, as time from the start of the auto focus operation until
`focus is achieved is considered to be constant.
`What is claimed is:
`
`1. An image pickup device having an auto focus function,
`comprising:
`a display for displaying pictures taken in from a lens; and
`a control unit for controlling to display a focal mark
`showing the focal condition on said display unit and
`changing the focal mark according to an elapsed time
`from the start of the auto focus operation until focus is
`achieved.
`
`2. The image pickup device according to claim 1, wherein
`said control unit changes the form, color or display position
`of said focal mark.
`
`3. The image pickup device according to claim 1, wherein
`an auto focus operation determines a focal
`location by
`driving the lens in sequence to multiple locations configured
`in advance, and wherein the control unit changes the focal
`mark according to driving of the lens to each location.
`4. The image pickup device according to claim 1,
`wherein, during the focal mark is being changed based on a
`first elapsed time that was planned, from the start of the auto
`focus operation until focus is achieved, when a remaining
`time of the first elapsed time until focus is achieved changes
`due to the progress of the auto focus operation, the control
`unit updates of changes in the focal mark according to
`changes in the remaining time.
`5. A method for notifying about the focusing time in an
`auto focus operation, comprising the steps of:
`displaying a focal mark showing the focal state, when
`displaying images taken in from a lens; and
`changing the focal mark according to an elapsed time
`from the start of the auto focus operation until focus is
`achieved.
`
`11
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`11
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`