Patent ID: 12244925

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following, an example of embodiments of a selection method, an imaging method, and an imaging apparatus according to the technology of the present disclosure will be described with reference to the accompanying drawings.

First Embodiment

As shown inFIG.1as an example, an imaging apparatus10which is an example of an “imaging apparatus” according to the technology of the present disclosure captures an imaging target region12designated as a subject. A range of the imaging target region12is determined by an angle of view designated by a user of the imaging apparatus10(hereinafter, referred to as the “user”). In the example shown inFIG.1, a person14and a road16are included in the imaging target region12. Moreover, in the example shown inFIG.1, an aspect is shown in which the person14stands on the road16.

For example, the imaging apparatus10is a lens-interchangeable digital camera. The imaging apparatus10comprises an imaging apparatus body18and an interchangeable lens20. The interchangeable lens20is interchangeably attached to the imaging apparatus body18. It should be noted that, here, the lens-interchangeable digital camera is described as an example of the imaging apparatus10, but this is merely an example, and a digital camera with a fixed lens may be used. Moreover, the technology of the present disclosure is established even for a digital camera mounted on various electronic apparatuses, such as a smart device, a wearable terminal, a cell observation device, an ophthalmologic observation device, or a surgical microscope.

In the imaging apparatus body18, a dial22, a release button24, a touch panel display26, an instruction key28, and the like are provided.

The dial22is operated in a case of setting an operation mode or the like. In the imaging apparatus10, various operation modes are selectively set by operating the dial22. The operation mode includes an operation mode of an imaging system. Examples of the operation mode of the imaging system include a live view imaging mode, an imaging mode for a still image, an imaging mode for a video, and a continuous imaging mode. The live view imaging mode is an operation mode for performing continuous imaging for a live view image (hereinafter, also referred to as “live view imaging”). The imaging mode for the still image is an operation mode for performing imaging for the still image accompanied by a main exposure for one frame. The imaging mode for the video is an operation mode for acquiring a video for recording by imaging the subject in accordance with a frame rate for the video (for example, several tens of fps). The continuous imaging mode is an operation mode for performing the continuous imaging (that is, the continuous imaging of the still image).

The release button24functions as an imaging preparation instruction unit and an imaging instruction unit, and a two-stage pressing operation of an imaging preparation instruction state indicating an imaging preparation instruction with respect to the imaging apparatus10and an imaging instruction state indicating an imaging instruction with respect to the imaging apparatus10can be detected. For example, the imaging preparation instruction state refers to a state in which the release button24is pushed to an intermediate position (half push position) from a standby position, and the imaging instruction state refers to a state in which the release button24is pushed to a final push position (full push position) beyond an intermediate position. It should be noted that, in the following, the “state in which the release button24is pushed to the half push position from the standby position” will be referred to as a “half push state”, and the “state in which the release button24is pushed to the full push position from the standby position” will be referred to as a “full push state”. Depending on the configuration of the imaging apparatus10, the imaging preparation instruction state may be a state in which a finger of the user is in contact with the release button24, and the imaging instruction state may be a state in which the finger of the user who performs the operation shifts from a state of being in contact with the release button24to a state of being separated from the release button24.

The release button24is also operated in a case in which a continuous imaging instruction is given to the imaging apparatus10. The continuous imaging is continuous imaging of the still image accompanied by the main exposure. In a situation in which the imaging mode is set for the imaging apparatus10, in a case in which the full push state of the release button24is continued for a certain time (for example, 0.5 seconds) or longer, the continuous imaging mode is set, and the continuous imaging is started. The continuous imaging is performed until the full push state is released. In the imaging apparatus10, the continuous imaging is realized by continuously performing the main exposure at predetermined time intervals. Here, the predetermined time interval refers to a time interval for one frame determined by, for example, a frame rate for the continuous imaging of several fps to several tens fps.

The touch panel display26comprises a display30and a touch panel32. Examples of the touch panel display26include an out-cell type, an on-cell type, or an in-cell type touch panel display. Examples of the display30include an organic EL display or a liquid crystal display.

The display30is also used for displaying the still image obtained by performing the imaging for the still image in a case in which the imaging apparatus10is instructed to capture the still image via the release button24. Further, the display30is used for displaying a playback image and displaying a menu screen and the like in a case in which the imaging apparatus10is in a playback mode.

The touch panel32receives the instruction from the user. For example, the instruction from the user includes the imaging preparation instruction, the imaging instruction, the continuous imaging instruction, and the like. The imaging preparation instruction, the imaging instruction, the continuous imaging instruction, and the like are realized by performing an operation on a soft key. For example, by the user turning on the soft key displayed on the display30via the touch panel32, the imaging preparation instruction, the imaging instruction, the continuous imaging instruction, and the like are given to the imaging apparatus10.

The instruction key28receives various instructions. Here, the “various instructions” refers to various instructions, for example, an instruction for displaying the menu screen on which various menus can be selected, an instruction for selecting one or a plurality of menus, an instruction for confirming a selected content, an instruction for deleting the selected content, zooming in, zooming out, and frame advance. Moreover, these instructions may be given by the touch panel32.

FIG.1shows an aspect in which a live view image34(image in which the imaging target region12is included as an image in the example shown inFIG.1) obtained by the imaging with the imaging apparatus10is displayed on the display30. The imaging apparatus10has an auto focus (AF) function, and an AF frame36is displayed on the live view image34in a superimposed manner. The imaging apparatus10performs the focusing on the subject included in the AF frame36, that is, the subject indicated by the image displayed in the AF frame36(that is, the subject in the real space).

A screen30A of the display30is a rectangle screen having a short side30A1and a long side30A2. The AF frame36is a rectangular frame and is displayed on a central portion30B of the screen30A. The AF frame36includes a plurality of regions38disposed in a matrix of 3×3. The region38is a region defined by a rectangular frame. The plurality of regions38are examples of a “plurality of candidate regions” according to the technology of the present disclosure.

An up-down direction40is set for the AF frame36. The up-down direction40is a direction along the short side30A1. Moreover, the up-down direction40is fixed in advance with respect to the AF frame36. Therefore, even in a case in which a posture of the imaging apparatus10is changed, the up-down direction40with respect to the AF frame36is not changed. That is, even in a case in which the posture of the imaging apparatus10is changed, the up-down direction40remains the direction along the short side30A1. For example, the up-down direction40with respect to the AF frame36is not changed regardless of whether the posture of the imaging apparatus10is changed from a horizontal direction to a vertical direction or from the vertical direction to the horizontal direction.

The plurality of regions38includes a central region42and a plurality of peripheral regions44. The plurality of peripheral regions44are disposed in all directions of the central region42to surround the central region42in the screen30A. The central region42is an example of a “first region” and a “central region” according to the technology of the present disclosure. Moreover, the plurality of peripheral regions44are examples of a “plurality of second regions” according to the technology of the present disclosure. Moreover, the peripheral region44is an example of a “peripheral region” according to the technology of the present disclosure.

In the example shown inFIG.1, eight peripheral regions44are shown as the plurality of peripheral regions44. In the example shown inFIG.1, the eight peripheral regions44refer to peripheral regions44A to44H. The peripheral regions44A to44C are positioned below the central region42in the up-down direction40, and are disposed along a direction (hereinafter, also referred to as “lateral direction”) orthogonal to the up-down direction40in the screen30A from a lower left side of a rear view of the horizontal imaging apparatus10shown inFIG.1to a lower right side of the rear view. The peripheral regions44D and44E are adjacent to each other in the lateral direction via the central region42. Specifically, the peripheral region44D is disposed on a left side of the rear view of the central region42in the horizontal imaging apparatus10shown inFIG.1, and the peripheral region44E is disposed on a right side of the rear view of the central region42in the horizontal imaging apparatus10shown inFIG.1. The peripheral regions44F to44H are positioned above the central region42in the up-down direction40and are disposed along the lateral direction from an upper left of the rear view of the horizontal imaging apparatus10shown inFIG.1to an upper right of the rear view.

As shown inFIG.2as an example, the plurality of regions38include the subject. The imaging method using the imaging apparatus10includes a step of imaging the subject included in the plurality of regions38. The subjects included in the plurality of regions38are a first subject46in the central region42and second subjects48A to48H in the peripheral regions44A to44H. The first subject46is an example of a “first subject” according to the technology of the present disclosure, and the second subjects48A to48H are examples of “a plurality of second subjects” according to the technology of the present disclosure. It should be noted that the “subject” is a person or an object included in each region38. For example, as shown inFIG.6, in a case in which one person is included in the plurality of regions38, a part of the person reflected in each region38is the “subject”.

The first subject46is included in the central region42. The second subject48A is included in the peripheral region44A. The second subject48B is included in the peripheral region44B. The second subject48C is included in the peripheral region44C. The second subject48D is included in the peripheral region44D. The second subject48E is included in the peripheral region44E. The second subject48F is included in the peripheral region44F. The second subject48G is included in the peripheral region44G. The second subject48H is included in the peripheral region44H. In the following, for convenience of description, in a case in which it is not necessary to distinguish between the second subjects48A to48H, the second subjects48A to48H will be referred to as a “second subject48”.

In the imaging apparatus10, distance measurement with respect to the plurality of regions38is performed. That is, in the imaging apparatus10, distances from a reference position of the imaging apparatus10(for example, an imaging surface52A of an image sensor50described below) to the first subject46and the plurality of second subjects48are calculated. In the first embodiment, the distance measurement is performed by a phase difference distance measurement method using phase difference pixels (for example, image plane phase difference pixels). It should be noted that the distance measurement by the phase difference distance measurement method using the image plane phase difference pixels is merely an example. The distance measurement by a time of flight (TOF) method using a TOF sensor may be used, or the distance measurement by a light detection and ranging (LiDAR) using a scanner may be used, and the distance measurement method may be any distance measurement method as long as the distance measurement with respect to the first subject46and the plurality of second subjects48can be realized.

As shown inFIG.3as an example, the imaging apparatus body18comprises the image sensor50. The image sensor50comprises a photoelectric conversion element52. The photoelectric conversion element52includes the imaging surface52A. The photoelectric conversion element52includes a phase difference pixel division region and a non-phase difference pixel division region. The phase difference pixel division region is a phase difference pixel group composed of a plurality of phase difference pixels, and receives subject light to generate phase difference image data as an electric signal in accordance with a light-receiving amount. The phase difference image data is used, for example, for the distance measurement. The distance measurement as used herein refers to, for example, processing of calculating a distance from the imaging surface52A to the subject (hereinafter, also referred to as a “subject distance”) from a calculation result obtained by performing a correlation calculation using the phase difference image data. The non-phase difference pixel division region is a non-phase difference pixel group composed of the plurality of non-phase difference pixels, and receives the subject light to generate non-phase difference image data as the electric signal in accordance with the light-receiving amount. The non-phase difference image data is, for example, image data indicating a visible light image and is used as a recording image or a display image (for example, the live view image34(seeFIG.1)).

The interchangeable lens20comprises an imaging lens54, a control device56, and an actuator58. The imaging lens54includes an objective lens54A, a focus lens54B, and the like. The objective lens54A and the focus lens54B are disposed in the order of the objective lens54A and the focus lens54B along an optical axis OA from a subject side (object side) to the imaging apparatus body18.

The control device56controls the entire interchangeable lens20in accordance with an instruction from the imaging apparatus body18. The control device56is a device including a computer including, for example, a processor (for example, a central processing unit (CPU)), a non-volatile memory (NVM), and a random access memory (RAM). It should be noted that, here, although the computer is described, this is merely an example, and a device including an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a programmable logic device (PLD) may be applied. Moreover, as the control device56, for example, a device realized by a combination of a hardware configuration and a software configuration may be used.

The actuator58comprises a focus slide mechanism (not shown) and a focus motor (not shown). The focus motor is connected to the control device56, and the drive of the focus motor is controlled by the control device56. The focus lens54B is attached to the focus slide mechanism to be slidable along the optical axis OA. Moreover, the focus motor is connected to the focus slide mechanism, and the focus slide mechanism is operated by receiving the power of the focus motor to move the focus lens54B along the optical axis OA. In the imaging apparatus10, the imaging apparatus body18performs the calculation of a focus position according to a subject distance (hereinafter, also referred to as an “AF calculation”), and moves the focus lens54B toward the calculated focus position thereby adjusting the focus. Here, the “focus position” refers to a position of the focus lens54B on the optical axis OA in an in-focus state.

The imaging apparatus body18comprises a controller60, an image memory62, a user interface (UI) system device64, an external interface (I/F)66, a photoelectric conversion element driver70, and an input/output interface72. Moreover, the image sensor50comprises a signal processing circuit74.

The controller60, an image memory62, the UI system device64, the external I/F66, the photoelectric conversion element driver70, and the signal processing circuit74are connected to the input/output interface72. Moreover, the control device56of the interchangeable lens20is also connected to the input/output interface72.

The controller60comprises a processor76, an NVM78, and a RAM80. The processor76, the NVM78, and the RAM80are connected to each other via a bus82, and the bus82is connected to the input/output interface72.

The NVM78is a non-transitory storage medium, and stores various parameters and various programs. For example, the NVM78is an electrically erasable programmable read-only memory (EEPROM). It should be noted that this is merely an example, and another type of non-volatile memory may be used. Moreover, the RAM80transitorily stores various pieces of information, and is used as a work memory.

The processor76is an example of a “processor” according to the technology of the present disclosure, and includes a CPU and a graphics processing unit (GPU). The GPU is operated under the control of the CPU, and is responsible for executing processing related to an image. It should be noted that the processor76may be at least one CPU. Moreover, a plurality of GPUs may be incorporated in the processor76. The processor76reads out a necessary program from the NVM78and executes the read out program on the RAM80. The processor76controls the entire imaging apparatus10in accordance with the program executed on the RAM80. In the example shown inFIG.3, the control device56, the image memory62, the UI system device64, the external I/F66, the photoelectric conversion element driver70, and the signal processing circuit74are controlled by the processor76.

Under the control of the photoelectric conversion element driver70, the photoelectric conversion element52photoelectrically converts the subject light received by the imaging surface52A, and outputs the electric signal in accordance with the light amount of the subject light to the signal processing circuit74as analog image data indicating the subject light.

The signal processing circuit74generates digital image data84by digitizing the analog image data read out from the photoelectric conversion element52. The digital image data84includes the phase difference image data and the non-phase difference image data, which are described above.

The image memory62stores the digital image data84generated by the signal processing circuit74. That is, the signal processing circuit74stores the digital image data84in the image memory62, under the control of the processor76. The processor76acquires the digital image data84from the image memory62, and executes various pieces of processing by using the acquired digital image data84.

The UI system device64comprises the display30, and the processor76displays various pieces of information on the display30. Moreover, the UI system device64comprises a reception device86. The reception device86comprises the touch panel32and a hard key unit88. The hard key unit88is a plurality of hard keys, and includes the dial22, the release button24, and the instruction key28(seeFIG.1). The processor76is operated in accordance with various instructions received by the reception device86.

The external I/F66controls the exchange of various pieces of information with and from a device (hereinafter, also referred to as an “external device”) that is present outside the imaging apparatus10. Examples of the external I/F66include a universal serial bus (USB) interface. The external device (not shown), such as a smart device, a personal computer, a server, a USB memory, a memory card, or a printer, is directly or indirectly connected to the USB interface. It should be noted that, in the first embodiment, although the hard key unit88is provided in the UI system device64, the technology of the present disclosure is not limited to this, and for example, the hard key unit88may be connected to the external I/F66.

By the way, in the imaging apparatus10, so-called zone AF is performed. In the zone AF, a region targeted for the AF is divided into a plurality of zones, the distance measurement is performed with respect to each zone, and the focusing is performed on the selected zone based on the distance measurement result (that is, the subject distance). Therefore, it is easier to image the subject than in the AF with respect to one region that is not divided into a plurality of zones, and this is also effective in imaging a moving object.

In the zone AF in the related art, the AF is performed based on an average value of the subject distances in all zones in a state in which, out of a central zone and a plurality of peripheral zones surrounding the central zone, weight higher than those of the plurality of peripheral zones is given to the central zone. However, in this case, the focusing on the subject that the user takes an interest may not be correctly performed. Moreover, there is a risk that the focus is out in a case in which a new subject enters the zone. In a case in which the focus is out, the focusing on the subject that the user takes an interest is not correctly performed.

Moreover, as a first method of the zone AF in the related art, a method is known in which the peripheral zones in front of the central zone (for example, the peripheral zones corresponding to the peripheral regions44A to44C shown inFIG.1) are prioritized to search for the subject which is a focusing target. Moreover, as a second method of the zone AF in the related art, a method is known in which the central zone (for example, the central zone corresponding to the central region42shown inFIG.1) is prioritized to search for the subject which is the focusing target. However, even in a case in which the first method is used, in a case in which the subject that the user takes an interest is included in a zone other than the front peripheral zones, the subject intended by the user is out of focus. Moreover, even in a case in which the second method is used, in a case in which the subject that the user takes an interest is included in a zone other than the central zone, the subject intended by the user is out of focus.

In view of such circumstances, the imaging apparatus10is configured to perform imaging processing (seeFIGS.4to12) by the processor76. As shown inFIG.4as an example, an imaging processing program90is stored in the NVM78. The processor76reads out the imaging processing program90from the NVM78, and executes the read out imaging processing program90on the RAM80. The processor76is operated as a first imaging controller76A, a first calculation unit76B, a first specifying unit76C, a first selection unit76D, and a display controller76E in accordance with the imaging processing program90executed on the RAM80to perform the imaging processing.

It should be noted that processing performed by the first imaging controller76A is an example of a “first imaging step” according to the technology of the present disclosure. Moreover, processing performed by the first calculation unit76B is an example of a “first calculation step” according to the technology of the present disclosure. Moreover, processing performed by the first specifying unit76C is an example of a “first specifying step” according to the technology of the present disclosure. Moreover, processing performed by the first selection unit is an example of a “first selection step” according to the technology of the present disclosure.

As shown inFIG.5as an example, the reception device86receives an instruction from the user or the like, and outputs a live view imaging start signal to the first imaging controller76A in accordance with the received instruction. For example, in a case in which the operation mode of the imaging system is set, the reception device86outputs the live view imaging start signal to the first imaging controller76A. In a case in which the live view imaging start signal is input, the first imaging controller76A controls the image sensor50via the photoelectric conversion element driver70to cause the image sensor50to perform the live view imaging.

The reception device86receives an instruction from the user or the like, and outputs an imaging preparation instruction signal to the first calculation unit76B in accordance with the received instruction. For example, in a case in which the imaging preparation instruction is received, the reception device86outputs the imaging preparation instruction signal to the first calculation unit76B. In a case in which the imaging preparation instruction signal is input, the first calculation unit76B performs the distance measurement with respect to the central region42and the plurality of peripheral regions44. In this case, for example, the first calculation unit76B acquires the digital image data84from the image memory62, and calculates a first distance which is the subject distance related to the first subject46(seeFIG.2) included in the central region42based on the phase difference image data included in the digital image data84. Moreover, for example, the first calculation unit76B calculates a plurality of second distances based on the phase difference image data included in the digital image data84. The plurality of second distances are a plurality of subject distances related to the plurality of second subjects48(seeFIG.2) included in the plurality of peripheral regions44.

In the first embodiment, the distance measurement is performed with respect to a plurality of portions of the first subject46. Therefore, the plurality of subject distances are calculated for the first subject46. The first calculation unit76B acquires the shortest subject distance as the first distance from the plurality of subject distances of the first subject46. It should be noted that, here, the shortest subject distance among the plurality of subject distances for the first subject46is used as the first distance, but this is merely an example, and a representative subject distance for the first subject46need only be used as the first distance. Examples of the representative subject distance for the first subject46include an average value, a median value, and a mode value of the plurality of subject distances for the first subject46.

In the first embodiment, the distance measurement is performed with respect to a plurality of portions of the plurality of second subjects48for each of the plurality of peripheral regions44. Therefore, the plurality of subject distances are calculated for the plurality of second subjects48. The first calculation unit76B acquires the shortest subject distance as the second distance from the plurality of subject distances of the plurality of second subjects48. It should be noted that, here, the shortest subject distance among the plurality of subject distances for the second subjects48is used as the second distance, but this is merely an example, and a representative subject distance for the second subjects48need only be used as the second distance. Examples of the representative subject distance for the second subjects48include an average value, a median value, and a mode value of the plurality of subject distances for the second subjects48.

The display controller76E acquires the digital image data84used in the calculation by the first calculation unit76B and generates the live view image34based on the acquired digital image data84. In addition, the display controller76E displays the live view image34on the display and displays the AF frame36on the live view image34in a superimposed manner. It should be noted that, in the following, the live view image34on which the AF frame36is displayed in a superimposed manner is also referred to as the “live view image34with the AF frame36”.

As shown inFIG.6as an example, the first specifying unit76C acquires the first distance, the plurality of second distances, and the digital image data84from the first calculation unit76B. The first specifying unit76C determines whether or not the second distance satisfying a first condition is present among the plurality of second distances. For example, the first condition refers to a condition in which a distance is shorter than the first distance. Here, in a case in which the second distance satisfying the first condition is present among the plurality of second distances, the first specifying unit76C specifies a first specific region92, which corresponds to the second distance satisfying the first condition among the plurality of second distances, from among the plurality of peripheral regions44by using the digital image data84. In the example shown inFIG.6, each of the peripheral regions44A to44D is shown as the first specific region92which corresponds to the second distance satisfying the first condition.

As shown inFIG.7as an example, the first selection unit76D acquires the digital image data84from the first calculation unit76B. In a case in which the first specifying unit76C determines that the second distance satisfying the first condition is not present among the plurality of second distances (that is, in a case in which the plurality of second distances are equal to or larger than the first distance), the first selection unit76D selects the first subject46included in the central region42as a first in-focus subject94, which is the subject to be focused, by using the digital image data84.

On the other hand, in a case in which the first specific region92which corresponds to the second distance satisfying the first condition is specified by the first specifying unit76C, as shown inFIG.8as an example, the first selection unit76D acquires the digital image data84from the first specifying unit76C. In addition, the first selection unit76D calculates a first ratio, which is a ratio of the first specific region92to the plurality of peripheral regions44. For example, the first ratio is the number of the first specific regions92. It should be noted that this is merely an example, and the ratio may be a ratio of a total area of the plurality of peripheral regions44(in the example shown inFIG.8, the peripheral regions44A to44D), which are the first specific regions92, to a total area of the plurality of peripheral regions44, or need only be a value corresponding to the number of the first specific regions92.

The first selection unit76D selects the first in-focus subject94from among the first subject46and the second subjects48A to48H by using the digital image data84based on the first ratio. Specifically, first, the first selection unit76D determines whether or not the first ratio exceeds a first threshold value. For example, the first threshold value refers to the number of the peripheral regions44positioned below the central region42in the up-down direction40(here, for example, three peripheral regions44A to44C). The first threshold value is an example of a “threshold value” according to the technology of the present disclosure.

In a case in which a determination is made that the first ratio exceeds the first threshold value, the first selection unit76D selects the second subject48in the first specific region92as the first in-focus subject94. That is, in a case in which the first ratio exceeds the first threshold value, a determination is made that there is a higher probability that the user takes an interest in the second subject48in the first specific region92than in a case in which the first ratio is equal to or less than the first threshold value, and the second subject48in the first specific region92is selected as the first in-focus subject94.

In the example shown inFIG.8, the second subject48D included in the peripheral region44D specified as the first specific region92is selected as the first in-focus subject94. More specifically, the subject distance (that is, the second distance) of the person14that is the second subject48D included in the peripheral region44D is shorter than the subject distance (that is, the first distance) of the road16included in the central region42. Moreover, the subject distance (that is, the second distance) of the road16included in the peripheral regions44B and44C is shorter than the subject distance (that is, the first distance) of the road included in the central region42. In this case, the number of the peripheral regions44(that is, the first specific region92) which corresponds to the second distance satisfying the first condition of being shorter than the first distance is four, and exceeds three, which is the first threshold value. Therefore, in the example shown inFIG.8, the portion having the shortest subject distance among the plurality of second distances is selected as the first in-focus subject94. In the example shown inFIG.8, the portion of the head of the person14that overlaps the peripheral region44D is selected as the first in-focus subject94(see an oblique line hatched portion shown inFIG.8).

It should be noted that, here, although the form example is described in which the second subject48D included in the peripheral region44D specified as the first specific region92is selected as the first in-focus subject94, this is merely an example. For example, a portion positioned at the median value, the average value, or the mode value of the subject distances with respect to the second subjects48included in the first specific region92may be selected as the first in-focus subject94. Moreover, the first selection unit76D may compare the median values of the subject distances between the plurality of peripheral regions44specified as the first specific regions92and select the second subject48in the specified peripheral regions44as the first in-focus subject94based on the comparison result. For example, in this case, among the peripheral regions44A to44D specified as the first specific region92, the peripheral region44having the smallest median value of the subject distances is selected as the first in-focus subject94. Here, the median value is described, but the average value or the mode value may be used instead of the median value.

On the other hand, as shown inFIG.9as an example, in a case in which in a case in which a determination is made that the first ratio is equal to or less than the first threshold value (for example, the number of the first specific regions92is equal to or less than three), the first selection unit76D selects the first subject46in the central region42as the first in-focus subject94. That is, in a case in which the first ratio is equal to or less than the first threshold value, a determination is made that the number of the peripheral regions44having the probability that the user takes an interest is small and there is a higher probability that the user takes more interest in the central region42than the peripheral region44than in a case in which the first ratio exceeds the first threshold value, the first subject46in the central region42is selected as the first in-focus subject94.

In this way, in a case in which the first in-focus subject94is selected, as shown inFIG.10as an example, the first selection unit76D outputs first in-focus subject information96, which is information on the first in-focus subject94, to the first imaging controller76A. The first in-focus subject information96includes position specification information for specifying the position of the first in-focus subject94selected by the first selection unit76D. Here, the position of the first in-focus subject94refers to the position of the pixel corresponding to the first in-focus subject94in the image indicated by the digital image data84used for selecting the first in-focus subject94.

The first imaging controller76A acquires the subject distance corresponding to the first in-focus subject information96, which is input from the first selection unit76D, from the first calculation unit76B. For example, the subject distance corresponding to the first in-focus subject information96refers to the first distance or the second distance corresponding to the position of the pixel specified from the position specification information included in the first in-focus subject information96among the first distance and the plurality of second distances calculated by the first calculation unit76B.

It should be noted that, here, although the form example has been described in which the subject distance is acquired from the first calculation unit76B by the first imaging controller76A, this is merely an example. For example, the subject distance (first distance or second distance) corresponding to the first in-focus subject94in the image indicated by the digital image data84used for selecting the first in-focus subject94may be included in the first in-focus subject information96. In this case, the first imaging controller76A need only acquire the subject distance from the first in-focus subject information96input from the first selection unit76D.

The first imaging controller76A calculates the focus position by using the subject distance corresponding to the first in-focus subject information96. In addition, the first imaging controller76A controls the actuator58via the control device56to move the focus lens54B to the focus position. As a result, the focusing on the first in-focus subject94is realized.

On the other hand, the first selection unit76D outputs the digital image data84used for selecting the first in-focus subject94and the first in-focus subject information96to the display controller76E. The display controller76E displays the live view image34with the AF frame36on the display30based on the digital image data84and the first in-focus subject information96. The region38including the first in-focus subject94selected by the first selection unit76D is displayed on the AF frame36in an enhanced manner. The display in an enhanced manner refers to the display in which the region38including the first in-focus subject94selected by the first selection unit76D and the remaining region38can be distinguished from each other. For example, the display in an enhanced manner is realized by making the thickness, the density, the color, the line type, or the like of the contour of the region38including the first in-focus subject94selected by the first selection unit76D different from those of the remaining region38. It should be noted that, in the example shown inFIG.10, the peripheral region44D is displayed in an enhanced manner.

In a case in which the focusing is performed on the first in-focus subject94and the imaging instruction is received by the reception device86, as shown inFIG.11as an example, the first imaging controller76A performs a main exposure control with respect to the photoelectric conversion element driver70. The main exposure control refers to a control of causing the image sensor50to perform the imaging accompanied by the main exposure. For example, the imaging accompanied by the main exposure refers to processing of obtaining the digital image data84for all usable photosensitive pixels included in the imaging surface52A. The imaging accompanied by the main exposure includes processing of exposing all usable photosensitive pixels included in the imaging surface52A, outputting the analog image data to the signal processing circuit74from all the exposed photosensitive pixels, causing the signal processing circuit74to generate the digital image data84.

Next, an example of a flow of the imaging processing performed by the processor76of the imaging apparatus10will be described with reference to the flowchart shown inFIG.12.

In the imaging processing shown inFIG.12, first, in step ST10, the first imaging controller76A controls the photoelectric conversion element driver70to cause the image sensor50to perform the live view imaging and acquire the digital image data84. As a result, the digital image data84is stored in the image memory62(seeFIG.5). After the processing of step ST10is executed, the imaging processing shifts to step ST12.

In step ST12, the display controller76E acquires the digital image data84from the image memory62and generates the live view image34based on the acquired digital image data84. In addition, the display controller76E displays the live view image34with the AF frame36on the display30(seeFIG.5). After the processing of step ST12is executed, the imaging processing shifts to step ST14.

In step ST14, the first calculation unit76B acquires the digital image data84from the image memory62, and calculates the first distance related to the first subject46(seeFIG.2) and the plurality of second distances related to the plurality of second subjects48(seeFIG.2) based on the acquired digital image data84. After the processing of step ST14is executed, the imaging processing shifts to step ST16.

In step ST16, the first specifying unit76C determines whether or not the second distance satisfying the first condition is present among the plurality of second distances by using the first distance and the plurality of second distances which are calculated in step ST14(seeFIG.6). In step ST16, in a case in which the second distance satisfying the first condition is not present among the plurality of second distances, a negative determination is made, and the imaging processing shifts to step ST18. In step ST16, in a case in which the second distance satisfying the first condition is present among the plurality of second distances, a positive determination is made, and the imaging processing shifts to step ST20.

In step ST18, the first selection unit76D selects the first subject46(seeFIG.2) in the central region42as the first in-focus subject94(seeFIGS.7and9). After the processing of step ST18is executed, the imaging processing shifts to step ST28.

In step ST20, the first specifying unit76C specifies the first specific region92, which corresponds to the second distance satisfying the first condition, from among the plurality of peripheral regions44(seeFIG.6). After the processing of step ST20is executed, the imaging processing shifts to step ST22.

In step ST22, the first selection unit76D calculates the first ratio (seeFIG.8). That is, the first selection unit76D acquires the digital image data84in which the first specific region92is specified from the first specifying unit76C, and calculates the ratio of the first specific region92to the plurality of peripheral regions44as the first ratio based on the acquired digital image data84. After the processing of step ST22is executed, the imaging processing shifts to step ST24.

In step ST24, the first selection unit76D determines whether or not the first ratio calculated in step ST22exceeds the first threshold value (seeFIGS.8and9). In step ST24, in a case in which the first ratio is equal to or less than the first threshold value (seeFIG.9), a negative determination is made, and the imaging processing shifts to step ST18. In step ST24, in a case in which the first ratio exceeds the first threshold value (seeFIG.8), a positive determination is made, and the imaging processing shifts to step ST26.

In step ST26, the first selection unit76D selects the second subject48in the first specific region92as the first in-focus subject94(seeFIG.8). After the processing of step ST26is executed, the imaging processing shifts to step ST28.

In step ST28, the first imaging controller76A performs the focusing on the first in-focus subject94selected in step ST18or ST26(seeFIG.10). Moreover, the display controller76E displays the live view image34with the AF frame36on the display30and displays the region38corresponding to the first in-focus subject94in an enhanced manner (seeFIG.10). After the processing of step ST28is executed, the imaging processing shifts to step ST30.

In step ST30, the first imaging controller76A determines whether or not the imaging instruction is received by the reception device86. In step ST30, in a case in which the imaging instruction is not received by the reception device86, a negative determination is made, and the imaging processing shifts to step ST10. In step ST30, in a case in which the imaging instruction is received by the reception device86, a positive determination is made, and the imaging processing shifts to step ST32.

In step ST32, the first imaging controller76A performs the main exposure control with respect to the photoelectric conversion element driver70to cause the image sensor50to perform the imaging accompanied by the main exposure. As a result, the image memory62stores the digital image data84obtained by performing the imaging accompanied by the main exposure. After the processing of step ST32is executed, the imaging processing shifts to step ST34.

In step ST34, the first imaging controller76A determines whether or not a condition for ending the imaging processing (hereinafter, referred to as “imaging processing end condition”) is satisfied. A first example of the imaging processing end condition is a condition in which an instruction to end the imaging processing is received by the reception device86. A second example of the imaging processing end condition is a condition in which a certain time (for example, several tens of seconds) has elapsed without receiving the imaging instruction by the reception device86. In a case in which the imaging processing end condition is not satisfied in step ST34, a negative determination is made, and the imaging processing shifts to step ST10. In a case in which the imaging processing end condition is satisfied in step ST34, a positive determination is made, and the imaging processing ends.

As described above, in the imaging apparatus10, the first subject46and the second subjects48A to48H included in the plurality of regions38are imaged. Moreover, the first distance, which is the subject distance related to the first subject46, and the plurality of second distances, which are the plurality of subject distances related to the second subjects48A to48H, are calculated (seeFIG.5). Moreover, the first specific region92which corresponds to the second distance satisfying the first condition among the plurality of second distances is specified from among the plurality of peripheral regions44(seeFIG.6). In addition, the ratio of the first specific region92to the plurality of peripheral regions44is calculated as the first ratio (seeFIGS.8and9).

Here, for example, in a case in which the first ratio is large (for example, in a case in which the first ratio exceeds the first threshold value), a determination is made that there is a high probability that the user takes more interest in the second subject48in the first specific region92than the first subject46in the central region42. On the other hand, in a case in which the first ratio is small (for example, in a case in which the first ratio is equal to or less than the first threshold value), a determination is made that there is a high probability that the second subject48that the user takes an interest is not present among the plurality of peripheral regions44. Therefore, in a case in which the first ratio is large, the focusing intended by the user is more easily realized by performing the focusing on the second subject48in the first specific region92than by performing the focusing on the first subject46. On the other hand, in a case in which the first ratio is small, the focusing intended by the user is more easily realized by performing the focusing on the first subject46than by performing the focusing on the second subject48in the first specific region92. Therefore, in the imaging apparatus10, the first in-focus subject94, which is the subject to be focused, is selected from among the first subject46and the second subject48in the first specific region92based on the first ratio (seeFIGS.7to9).

As a result, it is possible to facilitate the focusing on the subject that the user takes interest. For example, in a case in which there is a high probability that the user takes more interest in the first subject46than the second subject48, the focusing on the first subject46can be performed. On the other hand, in a case in which there is a high probability that the user takes more interest in the second subject48than the first subject46, the focusing on the second subject48(that is, the second subject48in the first specific region92) that the user takes an interest can be performed. In other words, this means that it is difficult to perform the focusing on a subject that the user does not take interest.

Moreover, in the imaging apparatus10, the first specific region92corresponding to the second distance which is shorter than the first distance among the plurality of second distances is specified from among the plurality of peripheral regions44(seeFIG.6). As a result, the focusing is performed on the second subject48in the peripheral region44in which the subject distance is shorter than the subject distance related to the first subject46in the central region42. Therefore, in a case in which the subject that the user takes an interest is present on the front side (side closer to the user) of the first subject46in the central region42, it is possible to facilitate the focusing on the subject that the user takes an interest.

Moreover, in the imaging apparatus10, in a case in which the number of the first specific regions92(seeFIGS.7,8, and9) is equal to or less than the first threshold value (that is, 3) corresponding to the number of the peripheral regions44A to44C positioned below the central region42in the up-down direction40, a determination is made that there is a high probability that the second subject48that the user takes an interest is not present in the first specific region92. On the other hand, in a case in which the number of the first specific regions92exceeds the first threshold value, a determination is made that there is a high probability that the second subject48that the user takes an interest is present in the first specific regions92. Therefore, in the imaging apparatus10, in a case in which the number of the first specific regions92exceeds the first threshold value, the second subject48in the first specific region92is selected as the first in-focus subject94. Therefore, in a case in which the user takes an interest in the second subject48in the first specific region92, it is possible to facilitate the focusing on the second subject48that the user takes an interest.

Moreover, in the imaging apparatus10, in a case in which the plurality of second distances corresponding to the peripheral regions44A to44H are longer than the first distance corresponding to the central region42, a determination is made that there is a high probability that the user takes more interest in the first subject46in the central region42than the second subjects48A to48H in the peripheral regions44A to44H. Therefore, in the imaging apparatus10, in a case in which the plurality of second distances corresponding to the peripheral regions44A to44H are longer than the first distance corresponding to the central region42, the first subject46in the central region42is selected as the first in-focus subject94. Therefore, in a case in which the user takes an interest in the first subject46in the central region42, it is possible to facilitate the focusing on the first subject46that the user takes an interest.

It should be noted that, in the first embodiment described above, the form example has been described in which each of the four adjacent peripheral regions44A to44D is specified as the first specific region92(seeFIG.6), but this is merely an example, and the technology of the present disclosure is not limited to this. For example, the peripheral regions44which are not adjacent to each other may be specified as the first specific region92. In the example shown inFIG.13, each of the peripheral regions44A to44C and44H is specified as the first specific region92by the first specifying unit76C. The peripheral region44H specified as the first specific region92includes a bird98as a part of the second subject48H.

In this way, even in a case in which the peripheral region44H specified as the first specific region92is not adjacent to other peripheral regions44(in the example shown inFIG.13, the peripheral regions44A to44C) specified as the first specific region92, a determination is made that the number of the first specific regions92is “4”. In addition, “4” of the number of the first specific regions92is used as the first ratio and is compared with the first threshold value. In addition, in a case in which the same conditions as those of the embodiment described above are satisfied, the portion having the shortest subject distance related to the second subject48in the first specific region92is selected as the first in-focus subject94.

Second Embodiment

In the first embodiment described above, the form example has been described in which the imaging processing is performed by the processor76in accordance with the imaging processing program90(seeFIG.4). However, in the second embodiment, a case will be described in which the imaging processing is performed by the processor76in accordance with an imaging processing program100(seeFIG.14). It should be noted that, in the second embodiment described above, the same components as those in the first embodiment will be designated by the same reference numeral, the description of the components will be omitted, and the difference from the first embodiment will be mainly described.

As shown inFIG.14as an example, the imaging processing program100is stored in the NVM78. The processor76reads out the imaging processing program100from the NVM78, and executes the read out imaging processing program100on the RAM80. The processor76is operated as the first imaging controller76A, the first calculation unit76B, the first specifying unit76C, the first selection unit76D, the display controller76E, a second imaging controller76F, and a second selection unit76G in accordance with the imaging processing program100executed on the RAM80to perform the imaging processing according to the second embodiment.

It should be noted that processing performed by the second imaging controller76F is an example of a “second imaging step” according to the technology of the present disclosure. Moreover, processing performed by second selection unit76G is an example of a “second selection step” according to the technology of the present disclosure.

As shown inFIG.15as an example, in a case in which the live view imaging for one frame ends under the control of the first imaging controller76A, the second imaging controller76F determines whether or not a timing (hereinafter, also referred to as a “live view imaging timing”) at which the live view imaging of the next frame is performed has arrived. In a case in which the second imaging controller76F determines that the live view imaging timing has arrived, the second imaging controller76F causes the image sensor50to perform the live view imaging. As a result, as in the first embodiment described above, the first subject46and the second subjects48A to48H (seeFIG.2) are imaged, and the image memory62stores the digital image data84indicating the live view image for one frame. In addition, in the same manner as in the first embodiment described above, the first calculation unit76B calculates the first distance and the plurality of second distances based on the digital image data84.

In this way, in a case in which the first calculation unit76B calculates the first distance and the plurality of second distances, as shown inFIG.16as an example, the second selection unit76G acquires the first distance and a plurality of second distances from the first calculation unit76B. Based on the first distance and the plurality of second distances acquired from the first calculation unit76B, the second selection unit76G predicts each region38, that is, the focus positions of the first subject46included in the central region42and the second subjects48A to48H included in the peripheral regions44A to44H.

In addition, the second selection unit76G selects the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position among the plurality of predicted focus positions (that is, a plurality of focus positions with respect to the first subject46and the second subjects48A to48H) as a second in-focus subject102. In the example shown inFIG.16, a portion corresponding to the focus position based on the second distance which is the shortest subject distance among the plurality of subject distances which are results of the distance measurement performed with respect to the plurality of portions of the second subject48A (in the example shown inFIG.16, a portion of the person14which overlaps the peripheral region44A) is selected as the second in-focus subject102.

In this way, in a case in which the second in-focus subject102is selected, as shown inFIG.17as an example, the second selection unit76G outputs second in-focus subject information104, which is information on the second in-focus subject102, to the second imaging controller76F. The second in-focus subject information104includes position specification information for specifying the position of the second in-focus subject102selected by the second selection unit76G. Here, the position of the second in-focus subject102refers to the position of the pixel corresponding to the second in-focus subject102in the image indicated by the digital image data84used for selecting the second in-focus subject102.

The second imaging controller76F acquires the subject distance corresponding to the second in-focus subject information104, which is input from the second selection unit76G, from the first calculation unit76B. For example, the subject distance corresponding to the second in-focus subject information104refers to the first distance or the second distance corresponding to the position of the pixel specified from the position specification information included in the second in-focus subject information104among the first distance and the plurality of second distances calculated by the first calculation unit76B.

It should be noted that, here, although the form example has been described in which the subject distance is acquired from the first calculation unit76B by the second imaging controller76F, this is merely an example. For example, the subject distance (first distance or second distance) corresponding to the second in-focus subject102in the image indicated by the digital image data84used for selecting the second in-focus subject102may be included in the second in-focus subject information104. In this case, the second imaging controller76F need only acquire the subject distance from the second in-focus subject information104input from the second selection unit76G.

The second imaging controller76F calculates the focus position by using the subject distance corresponding to the second in-focus subject information104. In addition, the second imaging controller76F controls the actuator58via the control device56to move the focus lens54B to the focus position. As a result, the focusing on the second in-focus subject102is realized.

On the other hand, the second selection unit76G outputs the digital image data84used for selecting the second in-focus subject102and the second in-focus subject information104to the display controller76E. The display controller76E displays the live view image34with the AF frame36on the display30based on the digital image data84and the second in-focus subject information104. In the same manner as in the first embodiment described above, the region38including the second in-focus subject102selected by the second selection unit76G is displayed in the AF frame36in an enhanced manner. In the example shown inFIG.17, the peripheral region44A is displayed in an enhanced manner.

Next, an example of a flow of the imaging processing according to the second embodiment performed by the processor76of the imaging apparatus10will be described with reference to the flowcharts shown inFIGS.18A and18B.

It should be noted that, here, a step of performing the same processing as the processing shown in the flowchart shown inFIG.12is designated by the same step number as the flowchart shown inFIG.12, and the description thereof will be omitted. In the imaging processing shown inFIGS.18A and18Bis different from the imaging processing shown inFIG.12in that the processing of step ST30A is applied instead of the processing of step ST30and processing of step ST36to step ST50is added.

In step ST30A shown inFIG.18A, the first imaging controller76A determines whether or not the imaging instruction is received by the reception device86. In step ST30A, in a case in which the imaging instruction is received by the reception device86, a positive determination is made, and the imaging processing shifts to step ST32. In step ST30A, in a case in which the imaging instruction is not received by the reception device86, a negative determination is made, and the imaging processing shifts to step ST36shown inFIG.18B.

In step ST36shown inFIG.18B, the second imaging controller76F determines whether or not the live view imaging timing has arrived. In step ST36, in a case in which the live view imaging timing has not arrived, a negative determination is made, and the imaging processing shifts to step ST48. In step ST36, in a case in which the live view imaging timing has arrived, a positive determination is made, and the imaging processing shifts to step ST38.

In step ST38, the second imaging controller76F controls the photoelectric conversion element driver70to cause the image sensor50to perform the live view imaging and acquire the digital image data84. As a result, the digital image data84is stored in the image memory62(seeFIG.15). After the processing of step ST38is executed, the imaging processing shifts to step ST40.

In step ST40, the first calculation unit76B acquires the digital image data84from the image memory62, and calculates the first distance related to the first subject46(seeFIG.2) and the plurality of second distances related to the plurality of second subjects48(seeFIG.2) based on the acquired digital image data84. After the processing of step ST40is executed, the imaging processing shifts to step ST42.

In step ST42, the second selection unit76G predicts each region38(seeFIGS.1and2), that is, the focus positions of the first subject46included in the central region42and the second subjects48A to48H included in the peripheral regions44A to44H based on the first distance and the plurality of second distances calculated in step ST40. After the processing of step ST42is executed, the imaging processing shifts to step ST44.

In step ST44, the second selection unit76G selects the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position among the plurality of focus positions predicted in step ST42(that is, the plurality of focus positions with respect to the first subject46and the second subjects48A to48H) as the second in-focus subject102. After the processing of step ST44is executed, the imaging processing shifts to step ST46.

In step ST46, the second imaging controller76F performs the focusing on the second in-focus subject102selected in step ST44(seeFIG.17). Moreover, the display controller76E displays the live view image34with the AF frame36on the display30and displays the region38corresponding to the second in-focus subject102in an enhanced manner (seeFIG.17). After the processing of step ST46is executed, the imaging processing shifts to step ST48.

In step ST48, the second imaging controller76F determines whether or not the imaging instruction is received by the reception device86. In step ST48, in a case in which the imaging instruction is received by the reception device86, a positive determination is made, and the imaging processing shifts to step ST36. In step ST48, in a case in which the imaging instruction is not received by the reception device86, a negative determination is made, and the imaging processing shifts to step ST50.

In step ST50, the second imaging controller76F performs the main exposure control with respect to the photoelectric conversion element driver70to cause the image sensor50to perform the imaging accompanied by the main exposure. As a result, the image memory62stores the digital image data84obtained by performing the imaging accompanied by the main exposure. After the processing of step ST50is executed, the imaging processing shifts to step ST34shown inFIG.18A.

As described above, in the imaging apparatus10according to the second embodiment, after the live view imaging for one frame is performed in step ST10(seeFIG.18A) included in the imaging processing, the live view imaging for next one frame is performed in step ST38(seeFIG.18B). The fact that the live view imaging for the next one frame is performed in step ST38after the live view imaging for one frame is performed means that the live view imaging for the next one frame is performed in a state in which the focusing on the first in-focus subject94is performed (see step ST28ofFIG.18A). There is a high probability that the subject that is in focus at the present time is a subject that the user takes interest. For the subject that is in focus at the present time, there is a high probability that the next frame has a distance between the focus positions close to that of the previous frame.

In the imaging apparatus10according to the second embodiment, the subject of which the distance between the focus positions is close to that of the first in-focus subject94from among the first subject46and the second subjects48A to48H imaged in step ST38is selected as the second in-focus subject102to be focused. Specifically, among the first subject46and the second subjects48A to48H imaged in step ST38, the subject of which the distance between the focus positions is closest to that of the first in-focus subject94is selected as the second in-focus subject102. In addition, the focusing is performed on the selected second in-focus subject102(see step ST46inFIG.18B). As a result, the focusing on the subject that the user takes an interest can be continued across the frames.

It should be noted that, in the second embodiment described above, the focusing is taken over from the first in-focus subject94to the second in-focus subject102at an interval of one frame, this is merely an example, and the focusing may be taken over from the first in-focus subject94to the second in-focus subject102at intervals of several frames to several tens of frames. Moreover, although processing of step ST36to step ST48is performed at an interval of one frame, this may also be performed at intervals of several frames to several tens of frames.

Moreover, in the second embodiment described above, the form example has been described in which the subject of which the distance between the focus positions is close to that of the first in-focus subject94is selected as the second in-focus subject102from among the first subject46and the second subjects48A to48H imaged in step ST38, but this is merely an example. For example, a subject (for example, a subject having the shortest distance) of which the distance on a two-dimensional plane in a case in which front and rear frames overlap is close to the first in-focus subject94may be selected as the second in-focus subject102from among the first subject46and the second subjects48A to48H imaged in step ST38. Moreover, for example, a subject (for example, a subject having the shortest distance) of which the subject distance is close to the first in-focus subject94may be selected as the second in-focus subject102from among the first subject46and the second subjects48A to48H imaged in step ST38.

Moreover, in the second embodiment described above, the form example has been described in which the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position is selected as the second in-focus subject102from among the plurality of predicted focus positions, but the technology of the present disclosure is not limited to this. For example, a subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position in a range less than a predetermined distance (for example, several millimeters) may be selected as the second in-focus subject102from among the plurality of predicted focus positions.

In this case, for example, as shown inFIG.19, in the imaging processing, the processing of step ST43need only be inserted between the processing of step ST42and the processing of step ST44. In step ST43, the second selection unit76G determines whether or not the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position (for example, the focus position corresponding to the first in-focus subject94or the second in-focus subject102in the previous frame) in the range less than the predetermined distance is present among the plurality of focus positions predicted in step ST42. In step ST43, in a case in which the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position in the range less than the predetermined distance is not present among the plurality of focus positions predicted in step ST42, a negative determination is made, and the imaging processing shifts to step ST48. In step ST43, in a case in which the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position in the range less than the predetermined distance is present among the plurality of focus positions predicted in step ST42, a positive determination is made, and the imaging processing shifts to step ST44.

In this way, by performing the processing of step ST43in the imaging processing, the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position in a range exceeding the predetermined distance is not selected as the second in-focus subject102from among the plurality of focus positions predicted in step ST42. That is, the subject corresponding to the focus position that is significantly far from the current focus position is determined to be a subject having a probability that the user takes interest, and is not selected as the second in-focus subject102. Therefore, it is possible to suppress that the focusing is performed on a subject that the user does not take interest.

Third Embodiment

In the first and second embodiments described above, the form example has been described in which the AF frame36consisting of the regions38of 3×3 is used, but in the third embodiment, a form example will be described in which an AF frame41(seeFIG.20) consisting of regions39of 5×5. It should be noted that, in the third embodiment described above, the same components as those in the first and second embodiments will be designated by the same reference numeral, the description of the components will be omitted, and the difference from the first and second embodiments will be mainly described.

As shown inFIG.20as an example, the imaging apparatus10according to the third embodiment includes the AF frame41instead of the AF frame36described in the embodiments described above. The AF frame41is a rectangular frame that is one size larger than the AF frame36. The AF frame41includes a plurality of regions39. The plurality of regions39is an example of a “plurality of third regions” according to the technology of the present disclosure.

The plurality of regions39are disposed in a matrix of 5×5. The plurality of regions39included in the AF frame41consist of the central region42and a plurality of peripheral regions43. The plurality of peripheral regions43are peripheral regions43A to43X. The peripheral regions43A to43X include third subjects different from each other, respectively. The peripheral regions43A to43X include peripheral regions44A to44H as the peripheral regions43G,43H,43I,43L,43M,43P,43Q, and43R. That is, in the plurality of regions39, the plurality of regions38(seeFIG.1andFIG.2) disposed in a matrix of 3×3 state are included as the plurality of regions39(that is, the central region42and the peripheral regions43G,43H,43I,43L,43M,43P,43Q, and43R) disposed in a matrix state of 3×3.

In the AF frame41, the subject to be focused is selected in two stages of the regions39of 5×5 and the regions39of 3×3. In order to select the subject to be focused in two stages of the regions39of 5×5 and the regions39of 3×3, as shown inFIG.21as an example, an imaging processing program106is stored in the NVM78. The processor76reads out the imaging processing program106from the NVM78, and executes the read out imaging processing program106on the RAM80. The processor76is operated as the first imaging controller76A, the first calculation unit76B, the first specifying unit76C, the first selection unit76D, the display controller76E, the second imaging controller76F, the second selection unit76G, a second calculation unit76H, a second specifying unit76I, and a third selection unit76J in accordance with the imaging processing program106executed on the RAM80to perform the imaging processing according to the third embodiment.

It should be noted that processing performed by the second calculation unit76H is an example of a “second calculation step” according to the technology of the present disclosure. Moreover, processing performed by the second specifying unit76I is an example of a “second specifying step” according to the technology of the present disclosure. Moreover, processing performed by the third selection unit76J is an example of a “third selection step” according to the technology of the present disclosure.

As shown inFIG.22as an example, in a case in which the imaging preparation instruction is received, the reception device86outputs the imaging preparation instruction signal to the second calculation unit76H. The second calculation unit76H performs distance calculation processing for all the regions39in the AF frame41. The distance calculation processing is processing of performing the distance measurement on the central region42and all the peripheral regions43. In this case, for example, in the same manner as in the first embodiment described above, the second calculation unit76H calculates the first distance. Moreover, for example, the second calculation unit76H calculates a plurality of third distances based on the phase difference image data included in the digital image data84in the same manner as in calculating the first distance. The plurality of third distances are a plurality of subject distances related to all the third subjects (seeFIG.20) included in all the peripheral regions43in the AF frame41.

In the third embodiment, the distance measurement is performed with respect to a plurality of portions of the third subjects in the peripheral region43. Therefore, the plurality of subject distances are calculated for the third subjects in the peripheral region43. The second calculation unit76H acquires the shortest subject distance as the third distance from among the plurality of subject distances of the third subjects in the peripheral region43. It should be noted that, here, the shortest subject distance among the plurality of subject distances for the third subjects in the peripheral region43is used as the third distance, but this is merely an example, and a representative subject distance for the third subjects in the peripheral region43need only be used as the third distance. Examples of the representative subject distance for the third subjects in the peripheral region43include an average value, a median value, and a mode value of the plurality of subject distances for the third subjects in the peripheral region43.

The display controller76E acquires the digital image data84used in the calculation by the second calculation unit76H and generates the live view image34based on the acquired digital image data84. In addition, the display controller76E displays the live view image34on the display and displays the AF frame41on the live view image34in a superimposed manner. It should be noted that, in the following, the live view image34on which the AF frame41is displayed in a superimposed manner is also referred to as the “live view image34with the AF frame41”.

As shown inFIG.23as an example, the second calculation unit76H determines whether or not the distance calculation processing for all the regions39in the AF frame41succeeds (that is, whether or not the first distance related to the first subject46and the plurality of third distances related to the plurality of third subjects are calculated). In a case in which the distance calculation processing for all the regions39in the AF frame41succeeds, the second specifying unit76I acquires the first distance, the plurality of third distances, and the digital image data84from the second calculation unit76H. The second specifying unit76I determines whether or not the third distance satisfying the second condition is present among the plurality of third distances. For example, the second condition refers to a condition in which a distance is shorter than the first distance. Here, in a case in which the third distance satisfying the second condition is present among the plurality of third distances, the second specifying unit76I specifies a second specific region108, which corresponds to the third distance satisfying the second condition among the plurality of third distances, from among the plurality of peripheral regions43by using the digital image data84. In the example shown inFIG.23, each of the peripheral regions43A to43K is shown as the second specific region108which corresponds to the third distance satisfying the second condition.

On the other hand, in a case in which the distance calculation processing for all the regions39in the AF frame41fails (that is, at least one of the first distance related to the first subject46or the plurality of third distances related to the plurality of third subjects is not calculated by the second calculation unit76H), the second specifying unit76I does not specify the second specific region108. In addition, the same imaging processing as in the first or second embodiment (that is, the imaging processing using the regions39of 3×3) described above is executed by the processor76.

In a case in which the second specific region108which corresponds to the third distance satisfying the second condition is specified by the second specifying unit76I, as shown inFIG.24as an example, the third selection unit76J acquires the digital image data84from the second specifying unit76I. In addition, the third selection unit76J calculates a second ratio, which is a ratio of the second specific region108to the plurality of peripheral regions43. For example, the second ratio is the number of the second specific regions108. It should be noted that this is merely an example, and the ratio may be a ratio of a total area of the plurality of peripheral regions43(in the example shown inFIG.8, the peripheral regions43A to43K), which are the second specific regions108, to a total area of the plurality of peripheral regions43, or need only be a value corresponding to the number of the second specific regions108.

The third selection unit76J selects a third in-focus subject110to be focused from among the first subject46and the third subjects by using the digital image data84based on the second ratio. Specifically, first, the third selection unit76J determines whether or not the second ratio exceeds a second threshold value. For example, the second threshold value refers to the number of the peripheral regions43positioned below the central region42in the up-down direction40(here, for example, 10 peripheral regions43A to43J). In a case in which the third selection unit76J determines that the second ratio exceeds the second threshold value, the third selection unit76J selects the third subject in the second specific region108as the third in-focus subject110. That is, in a case in which the second ratio exceeds the second threshold value, a determination is made that there is a higher probability that the user takes an interest in the third subject in the second specific region108than in a case in which the second ratio is equal to or less than the second threshold value, and the third subject in the second specific region108is selected as the third in-focus subject110.

On the other hand, as shown inFIG.25as an example, in a case in which the third selection unit76J determines that the second ratio is equal to or less than the second threshold value, the first subject46in the central region42is selected as the third in-focus subject110. That is, in a case in which the second ratio is equal to or less than the second threshold value, a determination is made that the number of the peripheral regions43having the probability that the user takes an interest is small and there is a higher probability that the user takes more interest in the central region42than the peripheral region43than in a case in which the second ratio exceeds the second threshold value, the first subject46in the central region42is selected as the third in-focus subject110.

In this way, in a case in which the third in-focus subject110is selected, as shown inFIG.26as an example, the third selection unit76J outputs third in-focus subject information112, which is information on the third in-focus subject110, to the first imaging controller76A. The third in-focus subject information112includes position specification information for specifying the position of the third in-focus subject110selected by the third selection unit76J. Here, the position of the third in-focus subject110refers to the position of the pixel corresponding to the third in-focus subject110in the image indicated by the digital image data84used for selecting the third in-focus subject110.

The first imaging controller76A acquires the subject distance corresponding to the third in-focus subject information112, which is input from the third selection unit76J, from the second calculation unit76H. For example, the subject distance corresponding to the third in-focus subject information112refers to the first distance or the third distance corresponding to the position of the pixel specified from the position specification information included in the third in-focus subject information112among the first distance and the plurality of third distances calculated by the second calculation unit76H.

It should be noted that, here, although the form example has been described in which the subject distance is acquired from the second calculation unit76H by the first imaging controller76A, this is merely an example. For example, the subject distance (first distance or second distance) corresponding to the third in-focus subject110in the image indicated by the digital image data84used for selecting the third in-focus subject110may be included in the third in-focus subject information112. In this case, the first imaging controller76A need only acquire the subject distance from the third in-focus subject information112input from the third selection unit76J.

The first imaging controller76A calculates the focus position by using the subject distance corresponding to the third in-focus subject information112. In addition, the first imaging controller76A controls the actuator58via the control device56to move the focus lens54B to the focus position. As a result, the focusing on the third in-focus subject110is realized.

On the other hand, the third selection unit76J outputs the digital image data84used for selecting the third in-focus subject110and the third in-focus subject information112to the display controller76E. The display controller76E displays the live view image34with the AF frame41on the display30based on the digital image data84and the third in-focus subject information112. The region39including the third in-focus subject110selected by the third selection unit76J is displayed on the AF frame41in an enhanced manner. In the example shown inFIG.26, the peripheral region43K is displayed in an enhanced manner. It should be noted that, in a case in which the focusing is performed on the third in-focus subject110and the imaging instruction is received by the reception device86, the first imaging controller76A performs the main exposure control with respect to the photoelectric conversion element driver70(seeFIG.11).

As shown inFIG.27as an example, in a case in which the live view imaging for one frame ends under the control of the first imaging controller76A, the second imaging controller76F determines whether or not the live view imaging timing has arrived. In a case in which the second imaging controller76F determines that the live view imaging timing has arrived, the second imaging controller76F causes the image sensor50to perform the live view imaging. As a result, the first subject46and all the third subjects (seeFIG.20) are imaged, and the digital image data84indicating the live view image for one frame is stored in the image memory62. In addition, in the same manner as in the example shown inFIG.22, the second calculation unit76H executes the distance calculation processing for all the regions39in the AF frame41.

As shown inFIG.28as an example, the second calculation unit76H determines whether or not the distance calculation processing for all the regions39in the AF frame41succeeds. In a case in which the distance calculation processing for all the regions39in the AF frame41succeeds, the second selection unit76G acquires the first distance and the plurality of third distances from the second calculation unit76H. Based on the first distance and the plurality of third distances acquired from the second calculation unit76H, the second selection unit76G predicts the focus positions of the first subject46included in the central region42and the third subjects (seeFIG.20) included in the peripheral regions43A to43X.

In addition, the second selection unit76G selects the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position among the plurality of predicted focus positions (that is, a plurality of focus positions with respect to the first subject46and the plurality of third subjects) as a fourth in-focus subject114. In the example shown inFIG.28, a portion corresponding to the focus position based on the third distance which is the shortest subject distance among the plurality of subject distances which are results of the distance measurement performed with respect to the plurality of portions of the third subject included in the peripheral region43A (in the example shown inFIG.28, a portion of the person14which overlaps the peripheral region43A) is selected as the fourth in-focus subject114.

On the other hand, in the example shown inFIG.28, in a case in which the distance calculation processing for all the regions39in the AF frame41fails, the second selection unit76G does not select the fourth in-focus subject114. In addition, the same imaging processing as in the first or second embodiment (that is, the imaging processing using the regions38of 3×3) described above is executed by the processor76.

In this way, in a case in which the fourth in-focus subject114is selected by the second selection unit76G, as shown inFIG.29as an example, the second selection unit76G outputs fourth in-focus subject information116, which is information on the fourth in-focus subject114, to the second imaging controller76F. The fourth in-focus subject information116includes position specification information for specifying the position of the fourth in-focus subject114selected by the second selection unit76G. Here, the position of the fourth in-focus subject114refers to the position of the pixel corresponding to the fourth in-focus subject114in the image indicated by the digital image data84used for selecting the fourth in-focus subject114.

The second imaging controller76F acquires the subject distance corresponding to the fourth in-focus subject information116, which is input from the second selection unit76G, from the second calculation unit76H. For example, the subject distance corresponding to the fourth in-focus subject information116refers to the first distance or the third distance corresponding to the position of the pixel specified from the position specification information included in the fourth in-focus subject information116among the first distance and the plurality of third distances calculated by the second calculation unit76H.

It should be noted that, here, although the form example has been described in which the subject distance is acquired from the second calculation unit76H by the second imaging controller76F, this is merely an example. For example, the subject distance (first distance or third distance) corresponding to the fourth in-focus subject114in the image indicated by the digital image data84used for selecting the fourth in-focus subject114may be included in the fourth in-focus subject information116. In this case, the second imaging controller76F need only acquire the subject distance from the fourth in-focus subject information116input from the second selection unit76G.

The second imaging controller76F calculates the focus position by using the subject distance corresponding to the fourth in-focus subject information116. In addition, the second imaging controller76F controls the actuator58via the control device56to move the focus lens54B to the focus position. As a result, the focusing on the fourth in-focus subject114is realized.

On the other hand, the second selection unit76G outputs the digital image data84used for selecting the fourth in-focus subject114and the fourth in-focus subject information116to the display controller76E. The display controller76E displays the live view image34with the AF frame41on the display30based on the digital image data84and the fourth in-focus subject information116. In the same manner as in the first embodiment described above, the region39including the fourth in-focus subject114selected by the second selection unit76G is displayed in the AF frame41in an enhanced manner. In the example shown inFIG.29, the peripheral region43A is displayed in an enhanced manner.

Next, an example of a flow of the imaging processing according to the third embodiment performed by the processor76of the imaging apparatus10will be described with reference to the flowcharts shown inFIGS.30A to30C.

It should be noted that, here, a step of performing the same processing as the processing shown in the flowchart shown inFIG.12is designated by the same step number as the flowchart shown inFIG.12, and the description thereof will be omitted. The imaging processing shown inFIGS.30A to30Cis different from the imaging processing shown inFIG.12in that processing of step ST60to step ST102is inserted before the processing of step ST10, the processing of step ST30B is applied instead of the processing of step ST30, the processing of step ST32is removed, and the processing of step ST34is removed.

In the imaging processing shown inFIG.30A, first, in step ST60, the first imaging controller76A controls the photoelectric conversion element driver70to cause the image sensor50to perform the live view imaging and acquire the digital image data84. As a result, the digital image data84is stored in the image memory62(seeFIG.22). After the processing of step ST60is executed, the imaging processing shifts to step ST62.

In step ST62, the display controller76E acquires the digital image data84from the image memory62and generates the live view image34based on the acquired digital image data84. In addition, the display controller76E displays the live view image34with the AF frame41on the display30(seeFIG.22). After the processing of step ST62is executed, the imaging processing shifts to step ST64.

In step ST64, the second calculation unit76H acquires the digital image data84from the image memory62and executes the distance calculation processing for all the regions39in the AF frame41based on the acquired digital image data84(seeFIG.22). After the processing of step ST64is executed, the imaging processing shifts to step ST66.

In step ST66, the second calculation unit76H determines whether or not the distance calculation processing for all the regions39in the AF frame41succeeds (seeFIG.23). In step ST66, in a case in which the distance calculation processing for all the regions39in the AF frame41fails, a negative determination is made, and the imaging processing shifts to step ST10shown inFIG.30C. In step ST66, in a case in which the distance calculation processing for all the regions39in the AF frame41succeeds, a positive determination is made, and the imaging processing shifts to step ST68.

In step ST68, the second specifying unit76I determines whether or not the third distance satisfying the second condition is present among the plurality of third distances (seeFIG.23) by using the first distance and the plurality of third distances calculated by executing the distance calculation processing in step ST64. In step ST68, in a case in which the third distance satisfying the second condition is not present among the plurality of third distances, a negative determination is made, and the imaging processing shifts to step ST10shown inFIG.30C. In step ST68, in a case in which the third distance satisfying the second condition is present among the plurality of third distances, a positive determination is made, and the imaging processing shifts to step ST70.

In step ST70, the second specifying unit76I specifies the second specific region108which corresponds to the third distance satisfying the second condition from the plurality of peripheral regions43. After the processing of step ST70is executed, the imaging processing shifts to step ST72.

In step ST72, the third selection unit76J calculates the second ratio (seeFIG.24). That is, the third selection unit76J acquires the digital image data84in which the second specific region108is specified from the second specifying unit76I, and calculates the ratio of the second specific region108to the plurality of peripheral regions43as the second ratio based on the acquired digital image data84. After the processing of step ST72is executed, the imaging processing shifts to step ST74.

In step ST74, the third selection unit76J determines whether or not the second ratio calculated in step ST72exceeds the second threshold value (seeFIGS.24and25). In step ST74, in a case in which the second ratio is equal to or less than the second threshold value (seeFIG.25), a negative determination is made, and the imaging processing shifts to step ST76. In step ST74, in a case in which the second ratio exceeds the second threshold value (seeFIG.24), a positive determination is made, and the imaging processing shifts to step ST78.

In step ST76, the third selection unit76J selects the first subject46in the central region42as the third in-focus subject110(seeFIG.25). After the processing of step ST76is executed, the imaging processing shifts to step ST80.

In step ST78, the third selection unit76J selects the third subject in the second specific region108as the third in-focus subject110(seeFIG.24). After the processing of step ST78is executed, the imaging processing shifts to step ST80.

In step ST80, the first imaging controller76A performs the focusing on the third in-focus subject110selected in step ST76or ST78(seeFIG.26). Moreover, the display controller76E displays the live view image34with the AF frame41on the display30and displays the region39corresponding to the third in-focus subject110in an enhanced manner (seeFIG.26). After the processing of step ST80is executed, the imaging processing shifts to step ST82.

In step ST82, the first imaging controller76A determines whether or not the imaging instruction is received by the reception device86. In step ST82, in a case in which the imaging instruction is not received by the reception device86, a negative determination is made, and the imaging processing shifts to step ST88shown inFIG.30B. In step ST82, in a case in which the imaging instruction is received by the reception device86, a positive determination is made, and the imaging processing shifts to step ST84.

In step ST84, the first imaging controller76A performs the main exposure control with respect to the photoelectric conversion element driver70to cause the image sensor50to perform the imaging accompanied by the main exposure. As a result, the image memory62stores the digital image data84obtained by performing the imaging accompanied by the main exposure. After the processing of step ST84is executed, the imaging processing shifts to step ST86.

On the other hand, in step ST88shown inFIG.30B, the second imaging controller76F determines whether or not the live view imaging timing has arrived. In step ST88, in a case in which the live view imaging timing has not arrived, a negative determination is made, and the imaging processing shifts to step ST102. In step ST88, in a case in which the live view imaging timing has arrived, a positive determination is made, and the imaging processing shifts to step ST90.

In step ST90, the second imaging controller76F controls the photoelectric conversion element driver70to cause the image sensor50to perform the live view imaging and acquire the digital image data84. As a result, the digital image data84is stored in the image memory62(seeFIG.27). After the processing of step ST90is executed, the imaging processing shifts to step ST92.

In step ST92, the second calculation unit76H acquires the digital image data84from the image memory62and executes the distance calculation processing for all the regions39in the AF frame41based on the acquired digital image data84(seeFIG.27). After the processing of step ST92is executed, the imaging processing shifts to step ST94.

In step ST94, the second calculation unit76H determines whether or not the distance calculation processing for all the regions39in the AF frame41succeeds (seeFIG.28). In step ST94, in a case in which the distance calculation processing for all the regions39in the AF frame41fails, a negative determination is made, and the imaging processing shifts to step ST10shown inFIG.30C. In step ST94, in a case in which the distance calculation processing for all the regions39in the AF frame41succeeds, a positive determination is made, and the imaging processing shifts to step ST96.

In step ST96, the second selection unit76G acquires the first distance and the plurality of third distances obtained by executing the distance calculation processing in step ST92, and predicts each region39(seeFIG.20), that is, the focus positions of the first subject46included in the central region42and the plurality of third subjects included in the peripheral regions43A to43X based on the acquired first distance and plurality of third distances. After the processing of step ST96is executed, the imaging processing shifts to step ST98.

In step ST98, the second selection unit76G selects the subject corresponding to the focus position at which the distance between the focus positions is the shortest distance from the current focus position among the plurality of focus positions predicted in step ST96(that is, the plurality of focus positions with respect to the first subject46and the plurality of third subjects) as the fourth in-focus subject114(seeFIG.28). After the processing of step ST98is executed, the imaging processing shifts to step ST100.

In step ST100, the second imaging controller76F performs the focusing on the fourth in-focus subject114selected in step ST98(seeFIG.29). Moreover, the display controller76E displays the live view image34with the AF frame41on the display30and displays the region39corresponding to the fourth in-focus subject114in an enhanced manner (seeFIG.29). After the processing of step ST100is executed, the imaging processing shifts to step ST102.

In step ST102, the second imaging controller76F determines whether or not the imaging instruction is received by the reception device86. In step ST102, in a case in which the imaging instruction is received by the reception device86, a positive determination is made, and the imaging processing shifts to step ST84shown inFIG.30A. In step ST102, in a case in which the imaging instruction is not received by the reception device86, a negative determination is made, and the imaging processing shifts to step ST88.

On the other hand, in the imaging processing shown inFIG.30C, processing of step ST10to step ST28described in the first embodiment described above is performed by the processor76. In step ST30B, the first imaging controller76A determines whether or not the imaging instruction is received by the reception device86. In step ST30B, in a case in which the imaging instruction is not received by the reception device86, a negative determination is made, and the imaging processing shifts to step ST18. In step ST30B, in a case in which the imaging instruction is received by the reception device86, a positive determination is made, and the imaging processing shifts to step ST84shown inFIG.30A.

In step ST86shown inFIG.30A, the first imaging controller76A determines whether or not the imaging processing end condition is satisfied. In a case in which the imaging processing end condition is not satisfied in step ST86, a negative determination is made, and the imaging processing shifts to step ST60. In a case in which the imaging processing end condition is satisfied in step ST86, a positive determination is made, and the imaging processing ends.

As described above, in the imaging apparatus10according to the third embodiment, the first distance related to the first subject46in the central region42included in the AF frame41(seeFIG.20) which is wider than the AF frame36(seeFIGS.1and2) and the plurality of third distances related to the plurality of third subjects in the peripheral regions43A to43X included in the AF frame41are calculated. In addition, the second specific region108which corresponds to the third distance satisfying the second condition among the plurality of third distances is specified from among the plurality of regions39(seeFIG.23). In addition, the ratio of the second specific region108to the plurality of peripheral regions43is calculated as the second ratio (seeFIGS.24and25).

Here, for example, in a case in which the second ratio is large (for example, in a case in which the second ratio exceeds the second threshold value), a determination is made that there is a high probability that the user takes more interest in the third subject in the second specific region108than the first subject46in the central region42. On the other hand, in a case in which the second ratio is small (for example, in a case in which the second ratio is equal to or less than the second threshold value), a determination is made that there is a high probability that the third subject that the user takes an interest is not present among the plurality of peripheral regions43. Therefore, in a case in which the second ratio is large, the focusing intended by the user is more easily realized by performing the focusing on the third subject in the second specific region108than by performing the focusing on the first subject46. On the other hand, in a case in which the second ratio is small, the focusing intended by the user is more easily realized by performing the focusing on the first subject46than by performing the focusing on the third subject in the second specific region108. Therefore, in the imaging apparatus10, the third in-focus subject110, which is the subject to be focused, is selected from among the first subject46and the third subject in the second specific region108based on the second ratio (seeFIGS.24and25).

As a result, it is possible to facilitate the focusing on the subject that the user takes an interest in the AF frame41(seeFIG.20) which is wider than the AF frame36(seeFIG.1andFIG.2). For example, in a case in which there is a high probability that the user takes more interest in the first subject46than the third subject, the focusing on the first subject46can be performed. On the other hand, in a case in which there is a high probability that the user takes more interest in the third subject than the first subject46, the focusing on the third subject (that is, the third subject in the second specific region108) that the user takes an interest can be performed. In other words, this means that it is difficult to perform the focusing on a subject that the user does not take an interest in the AF frame41which is wider than the AF frame36.

Moreover, in the imaging apparatus10according to the third embodiment, the second specific region108corresponding to the third distance which is shorter than the first distance among the plurality of third distances is specified from among the plurality of peripheral regions43(seeFIG.23). As a result, the focusing is performed on the third subject in the peripheral region43in which the subject distance is shorter than the subject distance related to the first subject46in the central region42. Therefore, in a case in which the subject that the user takes an interest is present on the front side (side closer to the user) of the first subject46in the central region42, it is possible to facilitate the focusing on the subject that the user takes an interest in the AF frame41(seeFIG.20) which is wider than the AF frame36(seeFIGS.1and2).

Moreover, in the imaging apparatus10according to the third embodiment, the AF frame41which is wider than the AF frame36is used. Therefore, the distance measurement for all the regions39in the AF frame41is less likely to succeed than the distance measurement for all the regions38in the AF frame36. In a case in which the distance measurement for all the regions39in the AF frame41does not succeed, in a case in which the focusing is always performed on the central region42and the subject that the user takes an interest is not present in the central region42, the focusing on the subject that the user does not take an interest is performed. In the imaging apparatus10according to the third embodiment, in a case in which the second specific region108is not specified due to the failure of the distance calculation processing for all the regions39, the imaging processing (for example, processing shown in step ST10to step ST28shown inFIG.30C) described in the first or second embodiment described above is performed. The imaging processing described in the first or second embodiment described above is the imaging processing using the AF frame36which is narrower than the AF frame41. Therefore, even in a case in which the second specific region108is not specified due to the failure of the distance calculation processing for all the regions39, in a case in which the subject that the user takes an interest is included in the peripheral region44in the AF frame36, the focusing can be performed on the second subject48in the peripheral region44instead of the first subject46in the central region42. As a result, it is possible to more facilitate the focusing on the subject that the user takes an interest than in a case in which the imaging processing is performed using only the AF frame41.

Moreover, in the imaging apparatus10according to the third embodiment, the imaging processing using the plurality of regions39disposed in a matrix of 5×5 and the imaging processing using the plurality of regions38disposed in a matrix of 3×3 are performed by two-stage method. Therefore, even in a case in which the second specific region108is not specified due to the failure of the distance calculation processing for the plurality of regions39, in a case in which the subject that the user takes an interest is included in the plurality of regions38, the focusing can be performed on the second subject48in the peripheral region44instead of the first subject46in the central region42. As a result, it is possible to more facilitate the focusing on the subject that the user takes an interest than in a case in which the imaging processing is performed using only the plurality of regions39disposed in a matrix of 5×5.

It should be noted that, in the third embodiment described above, the plurality of regions39disposed in a matrix of 5×5 and the plurality of regions38disposed in a matrix of 3×3 are described, but the technology of the present disclosure is not limited to this. For example, the imaging processing using the plurality of regions disposed in a matrix of 7×7 and the imaging processing using the plurality of regions39disposed in a matrix of 5×5 may be performed. That is, in a case in which N is an odd number of 3 or more, the imaging processing using a plurality of regions disposed in a matrix of N×N and the imaging processing using a plurality of regions disposed in a matrix of (N+2)×(N+2) need only be performed.

Moreover, in a case in which M is an even number of 2 or more, the imaging processing using a plurality of regions disposed in a matrix of N×N and the imaging processing using a plurality of regions disposed in a matrix of (N+M)×(N+M) may be performed.

Moreover, in the third embodiment described above, the form example has been described in which the imaging processing shifts to step ST34ofFIG.30Ain a case in which a negative determination is made in step ST30B shown inFIG.30C, but the technology of the present disclosure is not limited to this. For example, in a case in which a negative determination is made in step ST30B shown inFIG.30C, the processing shown in the flowchart ofFIG.18BorFIG.19may be performed by the processor76.

Fourth Embodiment

In the fourth embodiment, a form example of a case in which the continuous imaging is performed by the imaging apparatus10(that is, a case in which the continuous imaging mode is set for the imaging apparatus10) will be described. It should be noted that, in the fourth embodiment described above, the same components as those in the first to third embodiments will be designated by the same reference numeral, the description of the components will be omitted, and the difference from the first to third embodiments will be mainly described.

First, an example of a flow of processing of continuous imaging which is known in the related art will be described with reference toFIG.31. As shown inFIG.31as an example, the live view imaging is performed during a live view imaging period. During the live view imaging period, by performing the live view imaging, the non-phase difference image data included in the digital image data84is stored in the image memory62. In addition, the non-phase difference image data is read out from the image memory62by the processor76, and the image indicated by the read out non-phase difference image data is displayed on the display30as the live view image.

Moreover, during the live view imaging period, by performing the live view imaging, the phase difference image data included in the digital image data84is stored in the image memory62. The processor76reads out the phase difference image data from the image memory62, and calculates the subject distance related to a focus target region based on the read out phase difference image data. For example, the focus target region is a region in the AF frame36, a region in the AF frame41, or a region designated by the user via the reception device86.

It should be noted that the focus target region may be a fixed region, or may be a region in which a position in an imaging range is changed, for example, a region in which a specific moving object (for example, a specific person, a specific bicycle, a specific vehicle, or a specific aircraft), which is recognized by the processor76performing image recognition processing based on the image data, is followed.

During the live view imaging period, the processor76performs the AF calculation based on the calculated subject distance. Moreover, during the live view imaging period, the processor76predicts the focus position of the focus lens54B with respect to the focus target region at a timing at which the main exposure of the first frame of the continuous imaging is started, based on the focus position obtained by performing the AF calculation. The prediction of the focus position is performed, for example, based on a plurality of focus positions obtained by performing the latest plurality of AF calculations (for example, the latest two AF calculations retroactively from the present time) and an elapsed time from the completion of the prediction of the first frame of the continuous imaging to the present time. The processor76controls the actuator58via the control device56to move the focus lens54B along the optical axis OA toward the predicted focus position.

In a case in which the release button24is fully pushed and the full push state is continued for a certain time or longer, a timing for starting the continuous imaging (hereinafter, also referred to as a “continuous imaging start timing”) arrives. In a case in which the continuous imaging start timing has arrived, the live view image of the display30is hidden. That is, a display region in which the live view image is displayed is blacked out. Moreover, in a case in which the continuous imaging start timing has arrived, the continuous imaging is started.

The processor76stops the focus lens54B at the timing at which the main exposure is started. This is because, in a case in which the focus lens54B is moved during the main exposure, the distortion due to the movement of the focus lens54B occurs in the image obtained by the imaging. On the condition that the focus lens54B is stopped, first, the main exposure of the first frame of the continuous imaging is started.

While the main exposure of the first frame of the continuous imaging is performed, the processor76predicts the focus position of the focus lens54B with respect to the focus target region at a timing at which the main exposure of the second frame of the continuous imaging is performed, based on the latest focus position obtained by performing the AF calculation. Even in this case, the prediction of the focus position is performed based on, for example, a plurality of focus positions obtained by the latest plurality of AF calculations obtained during the live view imaging period, and the elapsed time from the completion of the prediction of the first frame of the continuous imaging to the present time.

After the main exposure of the first frame of the continuous imaging ends, the reading out of the digital image data84of the first frame of the continuous imaging is started. Here, the reading out of the digital image data84refers to processing up to the storage of the digital image data of the first frame of the continuous imaging in the image memory62and the storage of the digital image data84, which is read out from the image memory62by the processor76, in a predetermined storage region (here, as an example, the NVM78).

Moreover, in a case in which the main exposure of the first frame of the continuous imaging ends, the processor76calculates the subject distance based on the phase difference image data obtained by the main exposure, and performs the AF calculation based on the calculated subject distance. Moreover, the processor76predicts the focus position of the focus lens54B with respect to the focus target region at the timing at which the main exposure of the second frame of the continuous imaging is performed, based on the focus position obtained by performing the latest AF calculation.

Moreover, after the main exposure of the first frame of the continuous imaging ends, the focus lens54B starts moving toward the predicted focus position. In a case in which the reading out of the digital image data ends, the live view imaging for three frames is performed, and the image indicated by the non-phase difference image data obtained thereby is displayed on the display30as the live view image. It should be noted that, here, the live view imaging for three frames is described, but this is merely an example, and the live view imaging for one or two frames may be performed, the live view imaging for four or more frames may be performed, and the live view imaging for the number of frames determined in accordance with the frame rate of the live view imaging.

Moreover, each time the live view imaging is performed, the processor76performs the AF calculation based on the phase difference image data obtained by performing the live view imaging. In addition, each time the AF calculation is performed, based on a plurality of focus positions obtained from a latest plurality of AF calculations, the focus position of the focus lens54B with respect to the focus target region at a timing at which the main exposure of a next frame in the continuous imaging is performed is predicted by the processor76.

On the other hand, the focus lens54B continues to be moved toward the predicted focus position even while the live view imaging for three frames is performed while the main exposure of the first frame of the continuous imaging is performed. That is, the processor76continues to move the focus lens54B toward the predicted latest focus position while the live view imaging for three frames is performed.

In a case in which the live view imaging of the third frame ends, the processor76controls the actuator58via the control device56to move the focus lens54B along the optical axis OA toward the latest focus position predicted by performing the live view imaging of the third frame.

In each frame after the second frame of the continuous imaging, the same processing as the processing of the first frame of the continuous imaging after the continuous imaging start timing has arrived is performed until the release button24is released from the full push state.

In general, the main exposure of the continuous imaging is performed at regular time intervals. For example, the main exposure is performed once in each of a plurality of continuous frame periods, and the live view imaging of several frames (three frames in the example shown inFIG.31) is performed after the main exposure in each frame period.

However, in a case in which the frame period is fixed, the focus lens54B may not be able to reach the predicted latest focus position before the main exposure of the next frame period is started. This is because the latest focus position predicted by performing the last live view imaging in the frame period is too far from the current focus position.

In a case in which the focusing is prioritized over a release interval of the continuous imaging (that is, the time interval during which the main exposure of the continuous imaging is performed), the focus lens54B can reach the predicted latest focus position by extending the frame period without limit. However, in that case, as a matter of course, the number of frames per unit time obtained by performing the continuous imaging is less than that in a case in which the release interval of the continuous imaging is prioritized.

In view of such circumstances, the imaging apparatus10according to the fourth embodiment is configured to perform continuous imaging control processing (seeFIGS.32to38C) by the processor76. As shown inFIG.32as an example, a continuous imaging control processing program118is stored in the NVM78. The processor76reads out the continuous imaging control processing program118from the NVM78, and executes the read out continuous imaging control processing program118on the RAM80. The processor76is operated as a focus position calculation unit76K, a focus position prediction unit76L, and a controller76M in accordance with the continuous imaging control processing program118executed on the RAM80to perform the continuous imaging control processing.

It should be noted that processing performed by the focus position calculation unit76K and the focus position prediction unit76L is an example of a “first calculation step”, a “second calculation step”, and a “selection step” according to the technology of the present disclosure. Moreover, processing performed by the controller76M is an example of a “first movement step” and an “imaging step” according to the technology of the present disclosure.

As shown inFIG.33as an example, the controller76M performs an imaging control with respect to the image sensor50via the photoelectric conversion element driver70to cause the image sensor50to perform various types of imaging, such as the live view imaging and the continuous imaging. By performing the imaging as described above, the digital image data84is stored in the image memory62. The controller76M acquires the non-phase difference image data, which is included in the digital image data84from the image memory62, as the live view image data. The controller76M displays the image indicated by the live view image data on the display30as the live view image.

In a period from the live view imaging period to the arrival of the continuous imaging start timing, the focus position calculation unit76K acquires the latest phase difference image data from the image memory62, and calculates the subject distance related to the focus target region based on the acquired phase difference image data. In addition, the focus position calculation unit76K performs the AF calculation based on the calculated subject distance to calculate a current focus position of the focus lens54B with respect to the focus target region (hereinafter, referred to as a “current focus position”).

Focus position time-series information is stored in the RAM80. The focus position time-series information is information indicating the time series of the current focus position obtained each time the AF calculation is performed. The time series of the current focus position is, for example, the time series of the current focus position obtained by the AF calculation for the last three times. The focus position calculation unit76K updates the focus position time-series information by storing the calculated latest current focus position in the RAM80each time the current focus position is calculated. Here, as the time series of the current focus position, the time series of the current focus position obtained by the AF calculation for the last three times is described, but this is merely an example, and the time series of the current focus position need only be the time series of the current focus position obtained by the AF calculation for a plurality of times in the past, further, the AF calculation for a plurality of times in the past need only be the AF calculation for a plurality of times performed in a period close to the present time.

The focus position prediction unit76L predicts the focus position of the focus lens54B with respect to the focus target region in the first frame of the continuous imaging in the previous stage of the start of the continuous imaging by the image sensor50. Moreover, the focus position prediction unit76L predicts the focus position of the focus lens54B with respect to the focus target region of the subsequent frame (for example, the next frame) for each frame of the continuous imaging after the continuous imaging by the image sensor50is started. Specifically, the focus position prediction unit76L acquires the focus position time-series information from the RAM80, and predicts the focus position (hereinafter, also referred to as a “subsequent frame focus position”) of the focus lens54B with respect to the focus target region of the subsequent frame (for example, the next frame) based on the acquired focus position time-series information.

The controller76M performs a focus lens movement control. A lens control signal for instructing the movement of the focus lens54B toward the focus position predicted by the focus position prediction unit76L or instructing the stop of the focus lens54B is generated and output to the control device56. In the example shown inFIG.33, since the subsequent frame focus position is predicted by the focus position prediction unit76L, the lens control signal generated and output by the controller76M is, for example, a signal for instructing the movement of the focus lens54B toward the subsequent frame focus position predicted by the focus position prediction unit76L. The control device56operates the actuator58in response to the lens control signal input from the controller76M to move the focus lens54B along the optical axis OA toward the subsequent frame focus position.

As shown inFIG.34as an example, the controller76M calculates the focus movement amount based on the current focus position calculated by the focus position calculation unit76K and the subsequent frame focus position predicted by the focus position prediction unit76L. The focus movement amount is a movement amount for moving the focus lens54B along the optical axis OA. Moreover, the focus movement amount corresponds to the magnitude of a blurriness amount of the image obtained by the imaging with the image sensor50.

The controller76M determines whether or not the focus movement amount exceeds a first reference value. The first reference value is an example of a “threshold value” according to the technology of the present disclosure. For example, the first reference value is a value predetermined as the focus movement amount corresponding to the blurriness amount in which there is a risk that rear focus occurs. In a case in which the focus movement amount exceeds the first reference value, the controller76M outputs the lens control signal to the control device56to stop the focus lens54B for a certain time. The reason why the focus lens54B is stopped for a certain time is to stand by the change in the situation of the subject. Depending on the change in the situation of the subject, it is possible to escape from the state in which the rear focus occurs.

On the condition that the focus lens54B is stopped for a certain time, the focus position calculation unit76K calculates the subject distance and calculates the current focus position based on the calculated subject distance. Moreover, the focus position calculation unit76K updates the focus position time-series information by using the current focus position. In addition, the focus position prediction unit76L predicts the subsequent frame focus position by using the focus position time-series information.

The controller76M determines whether or not the focus movement amount exceeds a second reference value in a case in which the latest focus movement amount is equal to or less than the first reference value. The second reference value is a value which is less than the first reference value. The second reference value may be a fixed value predetermined based on a frame rate of the continuous imaging, a movement speed of the focus lens54B, or the like, or may be a variable value changed in accordance with an instruction given from the user or the like. In a case in which the focus movement amount exceeds the second reference value, the controller76M outputs the lens control signal to the control device56to move the focus lens54B along the optical axis OA in a limited range. On the other hand, in a case in which the focus movement amount is equal to or less than the second reference value, the controller76M outputs the lens control signal to the control device56to move the focus lens54B toward the subsequent frame focus position along the optical axis OA.

In a case in which the focus lens54B is moved along the optical axis OA by using the focus movement amount exceeding the second reference value as it is, there is a risk that the focus lens54B is out of the limited range or deviates from the subsequent frame focus position. Therefore, in a case in which the focus lens54B is moved in the limited range along the optical axis OA, the focus movement amount is adjusted such that the focus lens54B is not out of the limited range or does not deviate from the subsequent frame focus position. As shown inFIG.35as an example, in a case in which the focus lens54B is moved along the optical axis OA in the limited range, the controller76M acquires a coefficient from a function120and multiplies the acquired coefficient by the focus movement amount to adjust the focus movement amount. The function120defines a correlation between the blurriness amount and the coefficient. The coefficient is a value less than 1, and the blurriness amount is linearly decreased as the blurriness amount is increased, and the blurriness amount is fixed in a range equal to or more than a certain value.

After adjusting the focus movement amount, the controller76M outputs the lens control signal to the control device56to move the focus lens54B along the optical axis OA by the adjusted focus movement amount.

As shown inFIG.36as an example, in the continuous imaging mode, a release priority range, a focusing priority range, and a standby priority range are defined as a range of the focus movement amount. The release priority range is a range in which the continuous imaging at predetermined time (for example, a time defined in accordance with a default frame rate of the continuous imaging) intervals is prioritized. The focusing priority range is a range in which the focusing is prioritized even in a case in which the continuous imaging cannot be performed at predetermined time intervals. The standby priority range is a range in which the standby of the focus lens54B is prioritized. In the imaging apparatus10, in a case in which the continuous imaging is performed, the processor76performs the processing shown inFIGS.34and35, so that the focus lens54B is moved along the optical axis OA in the release priority range, the focusing priority range, or the standby priority range.

The release priority range is broadly classified into a range in which the focus movement amount is small and a range in which the focus movement amount is large. In a case in which the focus lens54B is moved in the release priority range, the controller76M adjusts the focus movement amount by using the coefficient (seeFIG.35) in the range in which the focus lens54B is linearly decreased in the function120in accordance with the blurriness amount, and moves the focus lens54B along the optical axis OA by the adjusted focus movement amount. In a range in which the focus movement amount is small in the release priority range, the controller76M moves the focus lens54B toward the subsequent frame focus position within a predetermined time. In a range in which the focus movement amount is large in the release priority range, the controller76M maximally moves the focus lens54B toward the subsequent frame focus position within the predetermined time.

In a case in which the focus lens54B is moved in the focusing priority range, the controller76M adjusts the focus movement amount by using a fixed coefficient in a range in which the blurriness amount is equal to or larger than a certain value in the function120, and moves the focus lens54B along the optical axis OA by the adjusted focus movement amount. In the focusing priority range, the controller76M moves the focus lens54B toward the subsequent frame focus position exceeding the predetermined time (that is, ignoring the predetermined time).

In the standby priority range, since the blurriness amount is large, it is predicted that the focus lens will be in the rear focus. Therefore, the controller76M stops the focus lens54B for a certain time. This is to stand by the change in the situation of the subject (that is, to stand by the situation in which the rear focus does not occur).

FIG.37shows an example of a flow of the processing of the continuous imaging in a case in which the continuous imaging control processing is executed by the processor76. Up to the first frame of the live view imaging period and a continuous imaging period shown inFIG.37is the same as the first frame of the live view imaging period and the continuous imaging period shown inFIG.31. In the example shown inFIG.37, in the second frame of the continuous imaging, during a main exposure period, the processor76predicts the subsequent frame focus position based on the focus position time-series information. In addition, in a case in which the main exposure of the second frame of the continuous imaging ends, the processor76moves the focus lens54B toward the predicted latest subsequent frame focus position.

After the reading out of the digital image data84obtained by the main exposure ends, the processor76calculates the subject distance based on the phase difference image data included in the latest digital image data84, and performs the AF calculation based on the calculated subject distance. The processor76updates the focus position time-series information by using the current focus position obtained by performing the AF calculation. In addition, the processor76predicts the subsequent frame focus position based on the latest focus position time-series information, and continues the movement of the focus lens54B toward the predicted latest subsequent frame focus position.

Thereafter, in the second frame of the continuous imaging, the live view imaging of a predetermined number of frames (for example, three frames) is performed. The processor76calculates the subject distance based on the phase difference image data included in the latest digital image data84obtained each time the live view imaging is performed, and performs the AF calculation based on the calculated subject distance. The processor76updates the focus position time-series information by using the current focus position obtained by performing the AF calculation. In addition, the processor76predicts the subsequent frame focus position based on the latest focus position time-series information, and calculates the focus movement amount from the predicted latest subsequent frame focus position and the current focus position.

Here, the processor76executes the processing shown inFIGS.34and35by using the latest focus movement amount obtained after the live view imaging of the predetermined number of frames ends, thereby controlling the movement of the focus lens54B in the release priority range, the focusing priority range, or the standby priority range. In a case in which the focus lens54B is moved in the release priority range, the second frame of the continuous imaging ends within the predetermined time. In a case in which the focus lens54B is moved in the focusing priority range, the movement of the focus lens54B toward the subsequent frame focus position is continued, and the live view imaging is also continued. In the example shown inFIG.37, the live view imaging is not continued in the first frame of the continuous imaging, and the live view imaging is continued in the second frame of the continuous imaging. As a result, the number of frames of the live view image in the first frame of the continuous imaging is “3”, whereas the number of frames of the live view image in the second frame of the continuous imaging is “7”.

Next, an example of a flow of continuous imaging control processing performed by the processor76of the imaging apparatus10according to the fourth embodiment will be described with reference to the flowcharts shown inFIGS.38A to38D.

In the continuous imaging control processing shown inFIG.38A, in step ST200, the controller76M determines whether or not the live view imaging timing has arrived. In step ST200, in a case in which the live view imaging timing has not arrived, a negative determination is made, and the continuous imaging control processing shifts to step ST212. In step ST200, in a case in which the live view imaging timing has arrived, a positive determination is made, and the continuous imaging control processing shifts to step ST202.

In step ST202, the controller76M causes the image sensor50to perform the live view imaging. After the processing of step ST202is executed, the continuous imaging control processing shifts to step ST204.

In step ST204, the focus position calculation unit76K calculates the subject distance based on the phase difference image data included in the digital image data84obtained by performing the live view imaging in step ST202. The subject distance calculated in step ST204is an example of a “first distance which is a distance of a first subject included in first frame data of a first frame period” according to the technology of the present disclosure. Moreover, the processing of step ST204is an example of a “first calculation step” according to the technology of the present disclosure. After the processing of step ST204is executed, the continuous imaging control processing shifts to step ST206.

In step ST206, the focus position calculation unit76K calculates the current focus position based on the subject distance calculated in step ST204and stores the calculated current focus position in the RAM80to update the focus position time-series information. After the processing of step ST206is executed, the continuous imaging control processing shifts to step ST208.

In step ST208, the focus position prediction unit76L predicts the subsequent frame focus position based on the focus position time-series information. After the processing of step ST208is executed, the continuous imaging control processing shifts to step ST210.

In step ST210, the controller76M moves the focus lens54B toward the subsequent frame focus position predicted in step ST208. The processing of step ST210is an example of a “first movement step” according to the technology of the present disclosure. After the processing of step ST210is executed, the continuous imaging control processing shifts to step ST212.

In step ST212, the controller76M determines whether or not the continuous imaging start timing has arrived. In step ST212, in a case in which the continuous imaging start timing has not arrived, a negative determination is made, and the continuous imaging control processing shifts to step ST200. In step ST212, in a case in which the continuous imaging start timing has arrived, a positive determination is made, and the continuous imaging control processing shifts to step ST214.

It should be noted that a period from the execution of the processing of step ST200to the positive determination of step ST212is an example of a “first frame period” according to the technology of the present disclosure. Moreover, the digital image data84obtained by performing the live view imaging in step ST202is an example of “first frame data” according to the technology of the present disclosure.

In step ST214, the controller76M stops the focus lens54B. After the processing of step ST214is executed, the continuous imaging control processing shifts to step ST216.

In step ST216, the controller76M causes the image sensor50to start the main exposure. After the processing of step ST216is executed, the continuous imaging control processing shifts to step ST218.

In step ST218, the focus position prediction unit76L acquires the focus position time-series information from the RAM80. After the processing of step ST218is executed, the continuous imaging control processing shifts to step ST220.

In step ST220, the focus position prediction unit76L predicts the subsequent frame focus position based on the focus position time-series information acquired in step ST218. After the processing of step ST220is executed, the continuous imaging control processing shifts to step ST222.

In step ST222, the controller76M determines whether or not the main exposure ends. In step ST222, in a case in which the main exposure does not end, a negative determination is made, and the determination in step ST222is made again. In step ST222, in a case in which the main exposure ends, a positive determination is made, and the continuous imaging control processing shifts to step ST224.

In step ST224, the controller76M reads out the digital image data84from the image sensor50and stores the read out digital image data84in the image memory62. After the processing of step ST224is executed, the continuous imaging control processing shifts to step ST226.

In step ST226, the controller76M starts the movement of the focus lens54B toward the subsequent frame focus position predicted in step ST220. After the processing of step ST226is executed, the continuous imaging control processing shifts to step ST228shown inFIG.38B.

In step ST228, the controller76M determines whether or not the live view imaging timing has arrived. In step ST228, in a case in which the live view imaging timing has not arrived, a negative determination is made, and the determination in step ST228is made again. In step ST228, in a case in which the live view imaging timing has arrived, a positive determination is made, and the continuous imaging control processing shifts to step ST230.

In step ST230, the controller76M causes the image sensor50to perform the live view imaging. After the processing of step ST230is executed, the continuous imaging control processing shifts to step ST232.

In step ST232, the focus position calculation unit76K calculates the subject distance based on the phase difference image data included in the digital image data84obtained by performing the live view imaging in step ST230. After the processing of step ST232is executed, the continuous imaging control processing shifts to step ST234.

In step ST234, the focus position calculation unit76K calculates the current focus position based on the subject distance calculated in step ST232and stores the calculated current focus position in the RAM80to update the focus position time-series information. After the processing of step ST234is executed, the continuous imaging control processing shifts to step ST236.

In step ST236, the focus position prediction unit76L acquires the focus position time-series information from the RAM80. After the processing of step ST236is executed, the continuous imaging control processing shifts to step ST238.

In step ST238, the focus position prediction unit76L predicts the subsequent frame focus position based on the focus position time-series information acquired in step ST236. After the processing of step ST238is executed, the continuous imaging control processing shifts to step ST240.

In step ST240, the controller76M determines whether or not a condition for ending the live view imaging (hereinafter, referred to as a “live view imaging end condition”) is satisfied. Examples of the live view imaging end condition include a condition in which the live view imaging is performed for a predetermined number of frames. In step ST240, in a case in which the live view imaging end condition is not satisfied, a negative determination is made, and the continuous imaging control processing shifts to step ST228. In step ST240, in a case in which the live view imaging end condition is satisfied, a positive determination is made, and the continuous imaging control processing shifts to step ST242shown inFIG.38C.

In step ST242shown inFIG.38C, the controller76M determines whether or not a timing for starting the main exposure (hereinafter, referred to as a “main exposure timing”) is satisfied. Examples of the main exposure timing include a timing at which the reset of the photoelectric conversion element52is completed. In step ST242, in a case in which the main exposure timing is not satisfied, a negative determination is made, and the determination in step ST242is made again. In a case in which the main exposure timing is satisfied in step ST242, a positive determination is made, and the continuous imaging control processing shifts to step ST244.

In step ST244, the controller76M stops the focus lens54B. The position of the focus lens54B that is stopped by first executing the processing of step ST244is an example of a “first position” according to the technology of the present disclosure. After the processing of step ST244is executed, the continuous imaging control processing shifts to step ST246.

In step ST246, the controller76M causes the image sensor50to start the main exposure. After the processing of step ST246is executed, the continuous imaging control processing shifts to step ST248.

In step ST248, the focus position prediction unit76L acquires the focus position time-series information from the RAM80. After the processing of step ST248is executed, the continuous imaging control processing shifts to step ST250.

In step ST250, the focus position prediction unit76L predicts the subsequent frame focus position based on the focus position time-series information acquired in step ST248. After the processing of step ST250is executed, the continuous imaging control processing shifts to step ST252.

In step ST252, the controller76M determines whether or not the main exposure ends. In step ST252, in a case in which the main exposure does not end, a negative determination is made, and the determination in step ST252is made again. In step ST252, in a case in which the main exposure ends, a positive determination is made, and the continuous imaging control processing shifts to step ST254.

In step ST254, the controller76M reads out the digital image data84from the image sensor50and stores the read out digital image data84in the image memory62. After the processing of step ST254is executed, the continuous imaging control processing shifts to step ST256.

In step ST256, the controller76M determines whether or not the live view imaging timing has arrived. In step ST256, in a case in which the live view imaging timing has not arrived, a negative determination is made, and the determination in step ST256is made again. In step ST256, in a case in which the live view imaging timing has arrived, a positive determination is made, and the continuous imaging control processing shifts to step ST258.

In step ST258, the controller76M causes the image sensor50to perform the live view imaging. After the processing of step ST258is executed, the continuous imaging control processing shifts to step ST260.

In step ST260, the focus position calculation unit76K calculates the subject distance based on the phase difference image data included in the digital image data84obtained by performing the live view imaging in step ST258. The subject distance calculated in step ST260is an example of a “second distance which is a distance of a second subject included in second frame data of a second frame period after the first frame period” according to the technology of the present disclosure. Moreover, the processing of step ST260is an example of a “second calculation step” according to the technology of the present disclosure. After the processing of step ST260is executed, the continuous imaging control processing shifts to step ST262.

In step ST262, the focus position calculation unit76K calculates the current focus position based on the subject distance calculated in step ST260and stores the calculated current focus position in the RAM80to update the focus position time-series information. After the processing of step ST262is executed, the continuous imaging control processing shifts to step ST264.

In step ST264, the focus position prediction unit76L acquires the focus position time-series information from the RAM80. After the processing of step ST264is executed, the continuous imaging control processing shifts to step ST266.

In step ST266, the focus position prediction unit76L predicts the subsequent frame focus position based on the focus position time-series information acquired in step ST264. After the processing of step ST266is executed, the continuous imaging control processing shifts to step ST268.

In step ST268, the controller76M determines whether or not the live view imaging end condition is satisfied. In step ST268, in a case in which the live view imaging end condition is not satisfied, a negative determination is made, and the continuous imaging control processing shifts to step ST256. In step ST268, in a case in which the live view imaging end condition is satisfied, a positive determination is made, and the continuous imaging control processing shifts to step ST270shown inFIG.38D.

In step ST270shown inFIG.38D, the controller76M calculates the focus movement amount based on the current focus position and the subsequent frame focus position which is predicted in step ST266. The focus movement amount calculated in step ST270is an example of a “movement amount” according to the technology of the present disclosure. After the processing of step ST270is executed, the continuous imaging control processing shifts to step ST272.

In step ST272, the controller76M determines whether or not the focus movement amount calculated in step ST270or ST284exceeds the first reference value. In step ST270, in a case in which the focus movement amount calculated in step ST270or ST284does not exceed the first reference value, a negative determination is made, and the continuous imaging control processing shifts to step ST286. In step ST272, in a case in which the focus movement amount calculated in step ST270or ST284exceeds the first reference value, a positive determination is made, and the continuous imaging control processing shifts to step ST274.

In step ST274, the controller76M stops the focus lens54B for a certain time. After the processing of step ST274is executed, the continuous imaging control processing shifts to step ST276.

In step ST276, the controller76M causes the image sensor50to perform the live view imaging. In addition, the focus position calculation unit76K calculates the subject distance based on the phase difference image data included in the digital image data84obtained by performing the live view imaging. After the processing of step ST276is executed, the continuous imaging control processing shifts to step ST278.

In step ST278, the focus position calculation unit76K calculates the current focus position based on the subject distance calculated in step ST276and stores the calculated current focus position in the RAM80to update the focus position time-series information. After the processing of step ST278is executed, the continuous imaging control processing shifts to step ST280.

In step ST280, the focus position prediction unit76L acquires the focus position time-series information from the RAM80. After the processing of step ST280is executed, the continuous imaging control processing shifts to step ST282.

In step ST282, the focus position prediction unit76L predicts the subsequent frame focus position based on the focus position time-series information acquired in step ST280. After the processing of step ST282is executed, the continuous imaging control processing shifts to step ST284.

In step ST284, the controller76M calculates the focus movement amount based on the current focus position and the subsequent frame focus position which is predicted in step ST282. The focus movement amount calculated in step ST284is an example of a “movement amount” according to the technology of the present disclosure. After the processing of step ST284is executed, the continuous imaging control processing shifts to step ST272.

In step ST286, a determination is made as to whether or not the focus movement amount calculated in step ST270or ST284exceeds the second reference value. In step ST286, in a case in which the focus movement amount calculated in step ST270or ST284exceeds the second reference value, a positive determination is made, and the continuous imaging control processing shifts to step ST288. In step ST286, in a case in which the focus movement amount calculated in step ST270or ST284does not exceed the second reference value, a negative determination is made, and the continuous imaging control processing shifts to step ST290.

In step ST288, the controller76M starts the movement of the focus lens54B in the limited range. That is, the controller76M starts the movement of the focus lens54B within the predetermined time toward the subsequent frame focus position predicted in step ST266or ST282. Here, the focus movement amount used for the movement of the focus lens54B is the focus movement amount adjusted by the coefficient obtained from the function120in accordance with the blurriness amount. By executing the processing of step ST288, the focus lens54B does not reach the subsequent frame focus position predicted in step ST266or ST282, but reaches a position closer to the position of the subsequent frame focus position predicted in step ST266or ST282than the position of the focus lens54B stopped in step ST244. A position which is a destination of the movement of the focus lens54B due to the execution of the processing of step ST288(for example, a position of the focus lens54B stopped in step ST244shown inFIG.38C) is an example of a “third position” according to the technology of the present disclosure. After the processing of step ST288is executed, the continuous imaging control processing shifts to step ST292.

In step ST290, the controller76M starts the movement of the focus lens54B toward the subsequent frame focus position predicted in step ST266or ST282. Here, the focus movement amount used for the movement of the focus lens54B is the focus movement amount adjusted by the coefficient obtained from the function120in accordance with the blurriness amount. By executing the processing of step ST290, the focus lens54B reaches the subsequent frame focus position predicted in step ST266or ST282. A position which is a destination of the movement of the focus lens54B due to the execution of the processing of step ST290(for example, a position of the focus lens54B stopped in step ST244shown inFIG.38C) is an example of a “second position” according to the technology of the present disclosure. After the processing of step ST290is executed, the continuous imaging control processing shifts to step ST292.

It should be noted that, in the continuous imaging control processing, the position which is the destination of the movement of the focus lens54B is selected by executing the processing of step ST270or the processing of step ST284and the processing of step ST286. The processing of step ST270, the processing of step ST284, and the processing of step ST286are examples of a “selection step” according to the technology of the present disclosure. Moreover, the processing of step ST288, the processing of step ST290, and the processing of step ST246are examples of an “imaging step” according to the technology of the present disclosure.

In step ST292, the controller76M determines whether or not a condition for ending the continuous imaging control processing (hereinafter, referred to as a “continuous imaging control processing end condition”) is satisfied. Examples of the continuous imaging control processing end condition include a condition in which the continuous imaging mode is released. In step ST292, in a case in which the continuous imaging control processing end condition is not satisfied, a negative determination is made, and the continuous imaging control processing shifts to step ST242shown inFIG.38C. In step ST292, in a case in which the continuous imaging control processing end condition is satisfied, a positive determination is made, and the continuous imaging control processing ends.

As described above, in the imaging apparatus10according to the fourth embodiment, the subject distance is calculated based on the digital image data84obtained by performing the live view imaging during the live view imaging period, which is a stage before the continuous imaging period (see step ST204). In addition, in the continuous imaging period, the focus lens54B is moved toward the subsequent frame focus position (see step ST220) predicted based on the subject distance calculated during the live view imaging period. Here, in a case in which the frame interval of the continuous imaging is determined by the time interval in which the release is prioritized, the main exposure may be started without causing the focus lens54B to reach the subsequent frame focus position, and a blurred image is obtained. On the other hand, in a case in which the focusing is prioritized while ignoring the frame interval of the continuous imaging, an image with less blur can be obtained, but the number of frames obtained by the continuous imaging is reduced.

In the imaging apparatus10according to the fourth embodiment, for example, the subject distance is calculated based on the digital image data84obtained in the live view imaging of the second frame of the continuous imaging, and the focus movement amount is calculated based on the calculated subject distance. In addition, depending on whether or not the focus movement amount exceeds the second reference value, whether the focus lens54B is caused to reach the predicted subsequent frame focus position or the focus lens54B is brought as close as possible to the predicted subsequent frame focus position is selected.

For example, in a case in which the focus movement amount exceeds the second reference value, a determination is made that the focus lens54B cannot reach the predicted subsequent frame focus position within the predetermined time. In this case, an option of bringing the focus lens54B as close as possible to the subsequent frame focus position is selected (see step ST288). In a case in which the focus movement amount is equal to or less than the second reference value, a determination is made that the focus lens54B can reach the predicted subsequent frame focus position within the predetermined time. In this case, an option of causing the focus lens54B to reach the predicted subsequent frame focus position is selected (see step ST290).

In a case in which the main exposure is performed after the focus lens54B reaches the predicted subsequent frame focus position, the main exposure in an in-focus state can be performed without widening the release interval. Moreover, in a case in which the main exposure is performed after the predicted subsequent frame focus position is brought as close as possible to the predicted position, the main exposure can be performed in a state close to the in-focus state without excessively widening the frame interval of the continuous imaging. Therefore, it is possible to achieve both the release and the focusing in a well-balanced manner. As a result, for example, in the case of the continuous imaging mode, it is possible to obtain an image with less blur without excessively reducing the speed of the continuous imaging.

Moreover, in the imaging apparatus10according to the fourth embodiment, in a case in which the calculated focus movement amount is too large, it is difficult to perform the focusing within the predetermined time. In a case in which the focus movement amount exceeds the first reference value, the focus lens54B is held for a certain time. In a case in which the situation of the subject is changed during this period, it can be expected that the focus movement amount which is calculated again is reduced. In a case in which the focus movement amount is small, it is possible to realize the main exposure in the in-focus state within the predetermined time or the main exposure in a state close to the in-focus state within the predetermined time.

It should be noted that, in the fourth embodiment described above, the case of the continuous imaging mode is described, but the technology of the present disclosure is not limited to this. For example, the technology disclosed in the fourth embodiment described above is applied to the imaging performed to continuously obtain a plurality of frames, such as the imaging performed to obtain a video for recording.

Moreover, in each of the embodiments described above, the form example has been described in which various programs are stored in the NVM78, but the technology of the present disclosure is not limited to this. For example, various programs may be stored in a portable computer-readable non-transitory storage medium, such as a solid state drive (SSD) or a USB memory. Various programs stored in the non-transitory storage medium are installed in the imaging apparatus10. The processor76executes various pieces of processing described in each of the embodiments described above in accordance with various programs.

Moreover, various programs may be stored in a storage device of another computer or server device connected to the imaging apparatus10via a network, and various programs may be downloaded in response to a request of the imaging apparatus10and are installed in the imaging apparatus10.

It should be noted that it is not necessary to store all of the various programs in the storage device of the other computer or server device connected to the imaging apparatus10or the NVM78, and a part of the various programs may be stored.

Moreover, although the imaging apparatus10shown inFIG.3includes the built-in controller60, the technology of the present disclosure is not limited to this, and for example, the controller60may be provided outside the imaging apparatus10.

In each of the embodiments described above, the form example has been described in which the technology of the present disclosure is realized by the software configuration, but the technology of the present disclosure is not limited to this, and a device including an ASIC, an FPGA, or a PLD may be applied. Moreover, a combination of the hardware configuration and the software configuration may be used.

The following various processors can be used as a hardware resource for executing the various pieces of processing described in each of the embodiments described above. Examples of the processor include a CPU which is a general-purpose processor functioning as the hardware resource for executing the various pieces of processing by executing software, that is, a program. Moreover, examples of the processor include a dedicated electronic circuit which is a processor having a circuit configuration designed to be dedicated for executing specific processing, such as the FPGA, the PLD, or the ASIC. A memory is built in or connected to any processor, and any processor executes the various pieces of processing by using the memory.

The hardware resource for executing various pieces of processing may be composed of one of the various processors or may be composed of a combination of two or more processors that are the same type or different types (for example, combination of a plurality of FPGAs or combination of a CPU and an FPGA). Moreover, the hardware resource for executing the various pieces of processing may be one processor.

As a configuring example of one processor, first, there is a form in which one processor is composed of a combination of one or more CPUs and software and the processor functions as the hardware resource for executing the various pieces of processing. Second, as represented by system-on-a-chip (SoC), there is a form in which a processor that realizes the functions of the entire system including a plurality of hardware resources for executing the various pieces of processing with a single integrated circuit (IC) chip. As described above, the various pieces of processing are realized by using one or more of various processors as the hardware resource.

Further, as the hardware structure of these various processors, more specifically, it is possible to use an electronic circuit in which circuit elements, such as semiconductor elements, are combined. Moreover, the various pieces of processing are merely examples. Therefore, it is needless to say that the deletion of an unneeded step, the addition of a new step, and the change of a processing order may be employed in a range not departing from the gist.

The description contents and the shown contents above are the detailed description of the parts according to the technology of the present disclosure, and are merely examples of the technology of the present disclosure. For example, the description of the configuration, the function, the action, and the effect above are the description of examples of the configuration, the function, the action, and the effect of the parts according to the technology of the present disclosure. Accordingly, it is needless to say that unneeded parts may be deleted, new elements may be added, or replacements may be made with respect to the description contents and the shown contents above in a range that does not deviate from the gist of the technology of the present disclosure. Moreover, in order to avoid complications and facilitate understanding of the parts according to the technology of the present disclosure, in the description contents and the shown contents above, the description of common technical knowledge and the like that do not particularly require description for enabling the implementation of the technology of the present disclosure are omitted.

In the present specification, the grammatical concept of “A or B” includes the concept of “any one of A or B” as well as the concept synonymous with “at least one of A or B”. That is, “A or B” includes meaning that it may be only A, only B, or a combination of A and B. Moreover, in the present specification, in a case in which three or more matters are associated and expressed by “or”, the same concept as “A or B” is applied.

All documents, patent applications, and technical standards described in the present specification are incorporated into the present specification by reference to the same extent as in a case in which the individual documents, patent applications, and technical standards are specifically and individually stated to be incorporated by reference.