JP2013109107A - Image pickup apparatus and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manual focusing auxiliary function to enable easy focusing by eliminating the need for a user to perform the operation of returning when passing through a best focus position.SOLUTION: An image pickup apparatus includes focus evaluation means that detects the focus state from picked-up images at a plurality of different focus positions, and calculates the focused focus position and focus proximity degree, and state detection means for detecting the state of manual focusing operation of a photographer. According to the focus proximity degree calculated by the focus evaluation means and the state of manual focusing detected by the state detection means, the focus control for detecting the focus state is made different.

Description

  The present invention relates to an imaging apparatus and a control method in the imaging apparatus.

  Conventionally, a technique for detecting a focus from an image is known. For example, a technique for performing wobbling control and detecting a focus position is known. A technique for informing the photographer of the in-focus position is also known. For example, Patent Document 1 below describes a technique for detecting a focus state from images picked up at a plurality of focus positions by wobbling control and displaying the focus position based on the detected focus state. Japanese Patent Application Laid-Open No. 2004-228561 describes a technique for performing focus detection using an image obtained by capturing an image for focus detection instead of an image for real-time display. Furthermore, Patent Document 3 below describes a technique for visually displaying a focus evaluation value during a manual focus operation in a hill-climbing autofocus method.

Japanese Patent Laid-Open No. 5-308552 JP 2010-160269 A JP 2007-279777 A

  However, the above Patent Documents 1 to 3 do not mention a configuration in which focus control is performed in accordance with the operation state of the focus ring and the degree of focus during manual focus operation. Therefore, even if the technique described in the document is used, in the manual focus mode, the photographer cannot know the direction to be operated in order to obtain a focused state. For example, if only the in-focus state is displayed, the photographer eventually needs to perform an operation of searching the in-focus position by rotating the focus ring.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a manual focus that can be easily focused without performing an operation of returning past the best focus position. It is an object of the present invention to provide a new and improved imaging apparatus capable of providing the above auxiliary function and a control method in the imaging apparatus.

  In order to solve the above-described problem, according to an aspect of the present invention, a focus evaluation unit that detects a focus state from captured images at a plurality of different focus positions and calculates a focus focus position and a degree of focus vicinity. And a state detection means for detecting the state of the manual focus operation of the photographer, and depending on the degree of focus proximity calculated by the focus evaluation means and the state of the manual focus operation detected by the state detection means Thus, there is provided an imaging apparatus that varies the focus control for detecting the in-focus state.

  According to such a configuration, the in-focus direction near the focus position is calculated even during manual focus operation.For example, the in-focus direction is notified to the photographer, and the focus ring is driven and controlled in this in-focus direction. As a result, the photographer can easily obtain the correct in-focus position. As a result, it is possible to obtain a focused focus position quickly and easily by a manual focus operation, even if it is not a skilled photographer. Further, even a skilled photographer can display auxiliary information for obtaining a focused focus position, so that a shooting operation can be facilitated in a scene where a subject in which the focused focus position is difficult to determine is captured.

  In addition, the imaging apparatus may further include a focus control unit that performs the focus control. In this case, the focus control unit periodically wobbles the focus lens when the rotational movement amount of the focus ring falls below a predetermined threshold value, and when the rotational movement amount of the focus ring exceeds a predetermined threshold value, The focus lens may be configured not to perform a wobbling operation. With such a configuration, a useless wobbling operation (for example, a wobbling operation is useless in such a case because a delicate in-focus search is not performed while the focus ring is largely rotated) is suppressed. Thus, effects such as reduction of driving power, prevention of wear of driving members, and improvement of durability of the electric system can be obtained.

  Further, it is preferable that the focus control means causes the focus lens to perform a wobbling operation with a movement amount determined according to at least an aperture value and the degree of focus.

  Further, it is preferable that the focus control means does not cause the focus lens to perform a wobbling operation when a zooming operation is performed. With such a configuration, a useless wobbling operation (for example, the focus focus position changes during a zooming operation, and thus a wobbling operation for searching for a focus direction in this case is useless) is driven. Effects such as reduction of electric power, prevention of wear of driving members, and improvement of durability of the electric system can be obtained.

  In addition, the imaging apparatus may further include an information display unit that displays information indicating the in-focus degree on the screen. With such a configuration, it is possible for the photographer to adjust the operation amount while checking the degree of focus vicinity during manual focus operation.

  Further, the information display means may be configured not to display information related to the in-focus vicinity degree on the screen when a zooming operation is performed. Since the focus position is changed during the zooming operation, it is not meaningful to display the degree of focus vicinity in such a case. On the other hand, by not displaying the in-focus vicinity degree during the zooming operation, it is possible to suppress power consumption required for display and sequential calculation of the in-focus vicinity degree.

  Further, the focus evaluation means detects the degree of focus vicinity for each of the plurality of divided imaging areas, and the information display means displays information indicating the degree of focus vicinity detected for each of the imaging areas. You may be comprised so that it may display on the screen area | region corresponding to an imaging area. With such a configuration, it is possible to easily grasp which area of the subject is in a state close to the focus position.

  The information display means may be configured to emphasize display of a screen area corresponding to the focused imaging area. With this configuration, it is possible to easily recognize which area of the subject is in focus.

  In order to solve the above problem, according to another aspect of the present invention, an in-focus state is detected from captured images at a plurality of different focus positions, and an in-focus focus position and an in-focus vicinity degree are calculated. A focus evaluation step, and a state detection step for detecting the state of the manual focus operation of the photographer, and the degree of focus vicinity calculated in the focus evaluation step and the state of the manual focus operation detected in the state detection step Accordingly, a control method in the imaging apparatus is provided in which the focus control for detecting the in-focus state is varied according to the condition.

  According to this configuration, since the in-focus direction in the vicinity of the in-focus position is calculated even during the manual focus operation, for example, the in-focus direction is notified to the photographer, and the focus ring is driven and controlled in this in-focus direction. By doing so, the photographer can easily obtain the correct in-focus position. As a result, it is possible to obtain a focused focus position quickly and easily by a manual focus operation, even if it is not a skilled photographer. Further, even a skilled photographer can display auxiliary information for obtaining a focused focus position, so that a shooting operation can be facilitated in a scene where a subject in which the focused focus position is difficult to determine is captured.

  The above control method may further include a focus control step for performing the focus control. In this case, in the focus control step, when the rotational movement amount of the focus ring falls below a predetermined threshold value, the focus lens is periodically wobbled, and when the rotational movement amount of the focus ring exceeds the predetermined threshold value, The focus lens may be controlled not to perform a wobbling operation. With such a configuration, a useless wobbling operation (for example, a wobbling operation is useless in such a case because a delicate in-focus search is not performed while the focus ring is largely rotated) is suppressed. Thus, effects such as reduction of driving power, prevention of wear of driving members, and improvement of durability of the electric system can be obtained.

  In the focus control step, the focus lens may be controlled to perform a wobbling operation with a movement amount determined according to at least the aperture value and the in-focus vicinity degree.

  Further, in the focus control step, the focus lens may be controlled not to perform a wobbling operation when a zooming operation is performed. With such a configuration, a useless wobbling operation (for example, the focus focus position changes during a zooming operation, and thus a wobbling operation for searching for a focus direction in this case is useless) is driven. Effects such as reduction of electric power, prevention of wear of driving members, and improvement of durability of the electric system can be obtained.

  In addition, the control method in the imaging apparatus may further include an information display step of displaying information indicating the degree of near focus on the screen. With such a configuration, it is possible for the photographer to adjust the operation amount while checking the degree of focus vicinity during manual focus operation.

  Further, in the information display step, when the zooming operation is performed, it may be controlled not to display information indicating the degree of near focus on the screen. Since the focus position is changed during the zooming operation, it is not meaningful to display the degree of focus vicinity in such a case. On the other hand, by not displaying the in-focus vicinity degree during the zooming operation, it is possible to suppress power consumption required for display and sequential calculation of the in-focus vicinity degree.

  Further, in the focus evaluation step, a focus proximity degree is detected for each of the plurality of divided imaging areas, and in the information display step, information indicating the focus proximity degree detected for each of the imaging areas is detected. You may control to display on the screen area | region corresponding to an imaging area. With this configuration, it is possible to easily grasp which area of the subject is in a state close to focusing.

  Further, in the information display step, control may be performed so as to emphasize the display of the screen area corresponding to the focused imaging area. With this configuration, it is possible to easily recognize which area of the subject is in focus.

  As described above, according to the present invention, it is possible to provide an auxiliary function of manual focus that can be easily focused without performing an operation of returning past the best focus position.

It is a figure showing an example of composition of an imaging device concerning one embodiment of the present invention. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment. It is an explanatory view for explaining a control method of the imaging device concerning the embodiment.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<Embodiment>
An embodiment of the present invention will be described. The present embodiment is characterized in that the focus control is switched according to the operation state and the degree of focus in the manual focus mode. In the following, first, the overall configuration of the imaging apparatus 10 according to the present embodiment will be briefly described, and then the characteristic control operation of the imaging apparatus 10 according to the present embodiment will be described in detail.

[Configuration of Imaging Device 10]
First, a configuration example of the imaging apparatus 10 according to the present embodiment will be described with reference to FIG. FIG. 1 is an explanatory diagram illustrating a configuration example of an imaging apparatus 10 according to the present embodiment.

  As shown in FIG. 1, the imaging apparatus 10 mainly includes an imaging optical system 11, an imaging element 12, an image signal processing circuit 13, a VRAM 14, an LCD driver 15, an LCD 16, a memory 17, and control means. 18, an operation member 19, a timing generator 20, a focus driving unit 21, and an aperture driving unit 22.

  For convenience of explanation, a CMOS (Complementary Metal Oxide Semiconductor) is assumed as the imaging element 12 and an LCD (Liquid Crystal Display) is assumed as the display unit. However, the configuration of the imaging apparatus 10 according to the present embodiment is limited to this. Not. For example, a CCD (Charge Coupled Device) may be used instead of the CMOS. Further, an ELD (Electro-Luminescence Display) can be used instead of the LCD.

(Overview of operation at power-on)
The imaging device 10 controls the imaging device 12 at the same time as the power is turned on, and executes exposure and reading of image data at regular intervals (for example, 1/60 second unit: hereinafter, this unit is referred to as 1 frame). . This image data is displayed on the LCD 16 in real time. In addition, the imaging device 10 calculates the luminance value of the subject from the image data, and controls the aperture, exposure time, and gain value so that the captured image has appropriate brightness. In addition to such operations, the imaging apparatus 10 according to the present embodiment is equipped with an auxiliary function that can be used by the photographer to detect the in-focus position in the manual focus mode. This auxiliary function is mainly realized by the function of the control means 18. Hereinafter, the overall functional configuration of the imaging apparatus 10 including the auxiliary function will be described in detail.

(Imaging optical system 11)
The imaging optical system 11 mainly includes a zoom lens 114, a diaphragm 112, a focus lens 113, and the like. The imaging optical system 11 is an optical system that forms an image of external light on the imaging device 12 and transmits light from the subject to the imaging device 12. The zoom lens 114 is a lens that changes the angle of view by changing the focal length. The position of the zoom lens 114 can be adjusted by manually rotating the zoom ring 115.

  The diaphragm 112 is a mechanism that adjusts the amount of light that passes therethrough. The diaphragm 112 is driven by the diaphragm driving means 22 in accordance with control by the control means 18. The focus lens 113 focuses the subject image on the imaging surface of the imaging device 12 by moving the position. Further, the focus lens 113 is driven by a focus driving unit in accordance with control by the control unit 18, or is driven by manually rotating the focus ring 115.

(Image sensor 12)
The imaging element 12 is a photoelectric conversion element capable of performing photoelectric conversion that converts light incident through the imaging optical system 11 into an electrical signal. Although not clearly shown in the figure, a CDS / AMP (correlated double sampling / amplifier) circuit, an A / D converter, and the like are provided in the subsequent stage of the image sensor 12. .

  The CDS / AMP circuit removes low-frequency noise contained in the electrical signal output from the image sensor 12 and amplifies the electrical signal to an arbitrary level. The A / D converter digitally converts the electrical signal output from the CDS / AMP circuit to generate a digital signal. The image pickup device 12 and the CDS / AMP circuit are driven according to the timing signal output from the timing generator 20. For example, the exposure period of the image sensor 12 and the charge readout timing are controlled according to the timing signal output from the timing generator 20.

(Image signal processing circuit 13)
The digital signal output through the image sensor 12 or the like is input to the image signal processing circuit 13. The image signal processing circuit 13 processes the input digital signal to generate image data that can be processed. For example, the image signal processing circuit 13 performs white balance adjustment, γ value adjustment, contour enhancement control, and the like on the digital signal to generate image data. Further, the image signal processing circuit 13 calculates the focus state evaluation value from the image data by the function of the focus state evaluation value calculation unit 131. This in-focus state evaluation value represents the sharpness of the subject in a predetermined image area. Using the focus state evaluation value of the image data captured at a plurality of focus positions, it is possible to evaluate the degree of focus. This in-focus state evaluation value is input to the control means 18.

  The image signal processing circuit 13 executes processing such as compression / decompression of image data. For example, the image signal processing circuit 13 compresses the image data in a compression format such as a JPEG compression format or an LZW compression format, and stores the compressed image data in the memory 17. Further, the image signal processing circuit 13 reads the compressed image data read from the memory 17 and expands the read compressed image data. Further, the image signal processing circuit 13 displays image data on the LCD 16. Further, the image signal processing circuit 13 synthesizes and displays the display content indicating the in-focus state and the like with the image by the function of the display image synthesis unit 132. The display image data obtained in this way is stored in the VRAM 14.

(VRAM14, LCD driver 15, LCD16)
A VRAM (Video RAM) 14 is a memory for image display and has a plurality of channels. Therefore, the VRAM 14 can simultaneously execute a process for inputting display image data from the memory 17 and a process for outputting image data to the LCD driver 15. The capacity of the VRAM 14 depends on the resolution of the LCD 16 and the maximum number of colors.

  The display image data stored in the VRAM 14 is read by the LCD driver 15. The LCD driver 15 displays the display image data read from the VRAM 14 on the LCD 16. The image data displayed on the LCD 16 includes, for example, display image data photographed in accordance with the imaging operation, live view display image data before the imaging operation, image data such as various setting screens and GUIs, the memory 17 or the like. There is image data stored in a recording medium (not shown).

(Memory 17)
As the memory 17, for example, SDRAM (Synchronous DRAM) can be used. This memory 17 is used for temporarily storing image data. The memory 17 has a storage capacity sufficient to store a plurality of image data. The memory 17 is used to sequentially hold image data at the time of focus control. Further, the memory 17 may store a control program for the control means 18. Writing / reading of image data to / from the memory 17 is controlled by, for example, the image signal processing circuit 13.

(Media controller (not shown))
Although not clearly shown in FIG. 1, the imaging apparatus 10 is normally mounted with a fixed or removable recording medium and a media controller for controlling writing / reading of image data to / from the recording medium. This media controller executes read / write control of setting information in addition to image data write / write control on the recording medium. Examples of the recording medium include an optical disk (CD, DVD, BD, etc.), a magneto-optical disk, a magnetic disk, and a semiconductor storage medium.

(Operation member 19)
By the way, an operation for starting imaging and various setting operations are performed using the operation member 19. Examples of the operation member 19 include an up / down / left / right key (cross key), a power switch, a mode dial, and a release button. When the operation member 19 is operated, an operation signal is input to the control means 18 in accordance with the operation. For example, when the release button is half-pressed, an operation signal for starting focus control is input to the control means 18 and focus control by the control means 18 is started. When the half-press of the release button is released, an operation signal for ending the focus control is input to the control means 18, and the focus control by the control means 18 is finished. When the release button is fully pressed, an operation signal for starting imaging is input to the control means 18.

(Control means 18)
Hereinafter, functions of the control means 18 will be described.

  The control means 18 has a proper exposure calculation function. This function is a function of calculating an appropriate value for the aperture amount of the aperture 112 and the shutter speed from an AE (Auto Exposure: automatic exposure) evaluation value calculated based on the luminance value of the image data by the image signal processing circuit 13. . When the aperture amount is calculated by the appropriate exposure calculation function, the control unit 18 controls the aperture driving unit 22 to drive the aperture 112 so that the calculated aperture amount is obtained. Note that the control unit 18 may be configured to control the exposure time, the gain value, and the like simultaneously with the stop 112.

  Further, the control means 18 has a focus control function. The processing content realized by this function is when the operation signal for starting focus control is received from the operation member 19 in the autofocus mode (operation during AF), and when the focus ring 115 is rotated in the manual focus mode (when MF). Operation).

  First, the AF operation will be described.

  Upon receiving the operation signal for starting the focus control, the control means 18 receives the focus lens 113 based on the AF (auto focus) evaluation value calculated by the image signal processing circuit 13 based on the luminance value of the image data. The in-focus position is calculated. Note that, for example, when the contrast detection method is employed, the AF evaluation value becomes lower as the focus position becomes the focus position where the contrast value reaches a peak and the distance from the focus position becomes larger. That is, the focus position at which the contrast value reaches a peak is detected, and the detected focus position is determined as the focus position. When the focus position is calculated, the control means 18 controls the focus drive means 21 to move the position of the focus lens 113 so that the focus position matches the focus position.

  Next, the MF operation will be described. One of the characteristic functions of the imaging apparatus 10 according to the present embodiment is the operation of the control unit 18 in the MF operation. Hereinafter, the MF operation of the control means 18 will be described.

  As shown in FIG. 1, the control unit 18 mainly includes a zoom focal length calculation unit 181, a focus position detection unit 182, a focus distance calculation unit 183, a manual focus operation state detection unit 184, a focus position / It has direction calculation means 185 and focus drive control means 186.

(Zoom focal length calculation means 181)
When the imaging optical system 11 is composed of a single focal lens, there is no change in the focal length. However, when the zoom lens 114 is mounted as in the imaging device 10, the photographer performs a zooming operation (rotation of the zoom ring 111). The focal length (hereinafter referred to as zoom focal length) changes depending on the operation. Therefore, the zoom focal length calculation unit 181 detects the zoom focal length from the output value of the variable resistor output in conjunction with the rotation of the zoom ring 111, for example. More specifically, after the zoom focal length calculation unit 181 performs A / D conversion on the resistance value of the variable resistor linked to the rotation position of the zoom ring 111, the resistance value and the zoom focal length prepared in advance are calculated. The zoom focal length is detected based on the correspondence data indicating the correspondence relationship.

  The zoom focal length thus detected is temporarily stored in the memory 17 or storage means (not shown) provided in the control means 18. Further, by comparing the zoom focal length at the time of previous imaging with the zoom focal length at the time of current imaging and determining whether or not the difference between them is greater than or equal to a predetermined value, it is possible to detect the presence or absence of a zooming operation. .

(Focus position detection means 182 and focus distance calculation means 183)
The focus position detection unit 182 moves the position of the focus lens 113 to a position where the focus position becomes Over∞ when the imaging apparatus 10 is activated. The position detection of the focus lens 113 with the focus position of Over∞ can be realized by, for example, providing a contact that is electrically short-circuited when the focus lens 113 reaches the position and detecting the short-circuit state. is there. After moving the focus lens 113 to the Over∞ position, the focus position detection unit 182 drives the focus lens 113 in the near direction side, and detects a state change from the short-circuit state to the non-short-circuit state. Then, the focus position detecting unit 182 sets the focus position at the detected timing as the reference position.

  The focus position detection unit 182 detects the focus position defined by the drive pulse amount of the actuator (stepping motor) when the focus lens 113 is moved from the reference position. The focus position detected by the focus position detection unit 182 is input to the focus distance calculation unit 183. When the focus position is input, the focus position calculation unit 183 calculates the focus distance based on the input focus position and the zoom focal length. For example, the focus distance calculation unit 183 holds a correspondence table that describes the correspondence relationship between the focus distance and the focus position for each zoom focal length. By referring to this correspondence table, the zoom focal length and the focus position can be obtained. Based on this, the focus distance can be calculated.

(Manual focus operation state detection means 184)
Manual focus operation state detection means 184 detects the rotation state of focus ring 115. The focus ring 115 of the imaging device 10 is provided with a detector for detecting the rotation direction and the relative rotation amount according to the rotation of the focus ring 115. Therefore, the manual focus operation state detection means 184 can detect the rotation state of the focus ring 115 based on the output from this detector. For example, the manual focus operation state detection means 184 periodically stores the output of the detector, compares the previously stored detection result with the detection result detected this time, and the amount of change per rotation direction and unit time. (Rotation degree) is detected.

(Focus position / direction detection means 185, focus drive control means 186)
The in-focus position / direction detection means 185 detects the in-focus position, and also moves the focus lens 113 in order to focus from the difference between the in-focus position and the current focus position (the focus position should be moved). Direction; hereinafter, in-focus direction) is calculated. At this time, the focus drive control unit 186 controls the focus lens 113 to perform a wobbling operation in order to obtain a difference in focus state evaluation value used for detection of the focus direction. Further, the focus position / direction detection unit 185 displays information on the calculated focus position and focus direction on the LCD 16.

  The configuration of the imaging device 10 according to the present embodiment has been described above. However, the detailed control operation of the control means 18 is not described here. Therefore, the control operation by the control unit 18 will be mainly described in detail below with reference to the flowcharts shown in FIGS. 6 to 13 and the explanatory diagrams shown in FIGS.

[Regarding Control Operation by Imaging Device 10]
First, the overall processing flow will be described with reference to FIG.

  As shown in FIG. 6, first, the imaging apparatus 10 acquires the focus position by the function of the focus position detection unit 182 and records it in the storage unit (S101). Further, the imaging apparatus 10 detects the zoom focal length by the function of the zoom focal length calculation unit 181 and records it in the storage unit (S102). Note that the zoom focal length at the time of previous imaging and the zoom focal length at the time of current imaging are recorded in the storage means. Next, the imaging device 10 compares the zoom focal length at the previous imaging recorded in the storage unit with the zoom focal length at the current imaging recorded in the storage unit by the function of the manual focus operation state detection unit 184 (S103), and the zoom focal length. Whether or not the zooming operation is being performed is determined from the change of S (S104).

  If the zooming operation is being performed, the imaging device 10 advances the process to step S105. On the other hand, when the zooming operation is not being performed, the imaging device 10 advances the process to step S106.

  When the process proceeds to step S105, the imaging apparatus 10 performs zoom tracking control (S105), and the process proceeds to step S118. The zoom tracking control process will be described in detail later with reference to FIG. On the other hand, when the process proceeds to step S106, the imaging apparatus 10 records the manual focus operation state detected by the function of the manual focus operation state detection unit 184 in the storage unit (S106). Furthermore, the imaging apparatus 10 records the focus state evaluation value calculated by the focus state evaluation value calculation unit 131 in the storage unit (S107), and advances the process to step S108.

  When the process proceeds to step S108, the imaging device 10 determines whether the data amount satisfies a predetermined condition (S108). If the predetermined condition is satisfied, the imaging device 10 advances the process to step S109. On the other hand, when the predetermined condition is not satisfied, the imaging device 10 advances the process to step S117.

  When the process has proceeded to step S109, the imaging apparatus 10 calculates the in-focus position and the in-focus direction by the function of the in-focus position / direction detection unit 185 (S109). The processing related to the calculation of the in-focus position and the in-focus direction will be described in detail later with reference to FIG. Next, the imaging apparatus 10 determines whether or not a manual focus operation has been performed (S110). When the manual focus operation is performed, the imaging device 10 advances the process to step S113. On the other hand, when the manual focus operation is not performed, the imaging device 10 advances the process to step S111.

  When the process proceeds to step S111, the imaging apparatus 10 displays the focus position and the focus direction (S111). Next, the imaging apparatus 10 performs a first control process (Wobbling Focus drive) described later by the function of the focus drive control unit 186 (S112), and advances the process to Step S118. On the other hand, when the process proceeds to step S113, the imaging apparatus 10 displays the validity of the focus position and the operation direction (S113). Next, the imaging apparatus 10 determines whether the operation change amount is smaller than a predetermined threshold (S114). If the operation change amount <the threshold value, the imaging apparatus 10 advances the process to step S115. On the other hand, when the operation change amount ≧ the threshold value, the imaging device 10 advances the process to step S116.

  When the process proceeds to step S115, the imaging device 10 performs the second control process (Wobbling + MF Focus drive) (S115), and the process proceeds to step S118. On the other hand, when the process proceeds to step S116, the imaging apparatus 10 performs a third control process (MF Focus drive) (S116), and the process proceeds to step S118. If the data amount does not satisfy the predetermined condition in the process of step S108 and the process proceeds to step S117, the imaging device 10 determines whether or not a manual focus operation has been performed (S117). When the manual focus operation is performed, the imaging device 10 advances the treatment to step S114. On the other hand, when the manual focus operation is not performed, the imaging device 10 advances the process to step S112.

  When the process proceeds to step S118 along any of the above-described flows, the imaging apparatus 10 determines whether a release (shutter release) operation has been performed (S118). When the release operation is performed, the imaging device 10 advances the process to step S119. On the other hand, when the release operation is not performed, the imaging device 10 returns the process to step S101.

  When the process has proceeded to step S119, the imaging apparatus 10 determines whether wobbling control has been performed (S119). When the wobbling control is performed, the imaging device 10 advances the process to step S120. On the other hand, when the wobbling control is not performed, the imaging device 10 advances the process to step S121. When the process proceeds to step S120, the imaging apparatus 10 returns the focus position to the reference position by the function of the focus driving unit 186 (S120), and the process proceeds to step S121. The imaging apparatus 10 that has proceeded to step S121 performs a release process (S121).

  The overall processing flow has been described above.

(About zoom tracking control)
Next, a process related to zoom tracking control performed in step S105 of FIG. 6 will be described with reference to FIG. This zoom tracking control is realized mainly by the function of the control means 18.

  Even when the focus position is the same, depending on the optical system, the current in-focus distance (focus distance) often changes due to a zooming operation. Therefore, a control process (zoom tracking control) is required to change the focus position according to the zoom focal length so that the focus distance does not change due to the zooming operation. Therefore, the imaging device 10 performs zoom tracking control when it is determined that a zooming operation is being performed.

  As illustrated in FIG. 7, the imaging apparatus 10 that has started zoom tracking control first acquires information on the previous zoom focal length from the storage unit (S131). Next, the imaging apparatus 10 acquires the current focus position and calculates the focus distance (S132). This focus distance is calculated from the zoom focal length at the previous shooting and the focus position at the current shooting. Next, the imaging apparatus 10 acquires information on the zoom focal length at the time of current photographing (S133). Next, the imaging apparatus 10 calculates a target focus position at the time of current photographing based on the zoom focal length detected at the time of current photographing and the focus distance at the time of previous photographing (S134). Next, the imaging apparatus 10 performs focus drive control using the difference between the focus position at the time of current shooting and the target focus position as a focus drive amount (S135).

  The zoom tracking control has been described above.

(About the calculation method of the focus position and focus direction)
Next, the focus position and focus direction calculation processing performed in step S109 of FIG. 6 will be described with reference to FIG. This calculation process is mainly realized by the function of the control means 18.

  As illustrated in FIG. 8, the imaging apparatus 10 that has started the detection process of the in-focus position and the in-focus direction acquires the latest focus position group and records it in the storage unit (S141). Further, the imaging apparatus 10 acquires the latest focus state evaluation value group and records it in the storage unit (S142). The in-focus state evaluation value is a result of calculating an evaluation value corresponding to the contrast value of each block (each divided region in the central region shown in FIG. 2) while reading out image data. In addition, as the latest focus position group and the latest focus state evaluation value group, for example, the image at the time of previous shooting, the image at the previous shooting, the focus position and the focus state evaluation value corresponding to the image at the current shooting Is used.

  Next, the imaging apparatus 10 resets the parameter n to 1 (S143). Next, the imaging apparatus 10 determines whether the parameter n is n ≦ the number of evaluation blocks (S144). If n ≦ the number of evaluation blocks, the imaging apparatus 10 advances the process to step S145. On the other hand, if n ≦ the number of evaluation blocks is not satisfied, the imaging apparatus 10 ends a series of processes related to the calculation of the focus position and the focus direction. Note that the processing in steps S144 to S150 is executed for each block while changing the position of the block while incrementing the parameter n.

  When the process proceeds to step S145, the imaging apparatus 10 determines whether the focus position cannot be calculated, the focus position is on the ∞ direction side, and the focus position is on the near distance direction side. Implement (S145). First, the imaging apparatus 10 determines whether or not the in-focus position can be calculated (S146). When the in-focus position can be calculated (E1 in FIG. 3), the imaging apparatus 10 advances the process to step S147. On the other hand, when the in-focus position cannot be calculated (E2 to E4 in FIG. 3), the imaging device 10 advances the process to step S151.

  When the process has proceeded to step S147, the imaging device 10 calculates a focus position (S147). Next, the imaging apparatus 10 calculates the in-focus direction and the shift amount (S148). These in-focus position and in-focus direction are calculated using the focus position group and the in-focus state evaluation value group recorded in the storage means. For example, as shown in FIG. 4, a straight line connecting a point corresponding to the maximum value of the three focus evaluation values and a point corresponding to the third value, and a second value obtained by mirror-inverting the inclination of the straight line. The in-focus position is calculated from the intersection of the straight line passing through the point corresponding to.

  On the other hand, in order to calculate the in-focus direction, in-focus state evaluation values at at least three focus positions are required. Because the in-focus state evaluation value represents the sharpness, the value becomes higher as the focus is relatively closer. However, when an object with a low contrast is imaged, the in-focus state evaluation value is large even at the in-focus position. This is because the in-focus state cannot be detected. Further, even when the blur is large, the focus state evaluation value hardly changes, so that the focus state cannot be detected.

  Now, when the processes of steps S147 and S148 are completed, the imaging device 10 advances the process to step S149. When the process proceeds to step S149, the imaging device 10 records the detection result of the in-focus position and the in-focus direction in the storage unit (S149). Next, the imaging apparatus 10 increments the parameter n by 1 (S150), updates the block to be evaluated, and returns the process to step S144.

  When the process proceeds to step S151 in step S146, the imaging device 10 determines whether or not the in-focus position is on the ∞ direction side (S151). When the in-focus position is on the ∞ direction side (E3 in FIG. 3), the imaging apparatus 10 advances the process to step S152. On the other hand, when there is no in-focus position on the ∞ direction side (E2 and E4 in FIG. 3), the imaging device 10 advances the process to step S153.

  When the process has proceeded to step S152, the imaging apparatus 10 determines the in-focus position on the ∞ direction side (S152), and the process proceeds to step S149. On the other hand, when the process has proceeded to step S153, the imaging device 10 determines whether or not the in-focus position is on the short distance direction side (S153). When the in-focus position is on the short distance direction side (E2 in FIG. 3), the imaging device 10 advances the process to step S154. On the other hand, when there is no in-focus position on the short distance direction side (E4 in FIG. 3), the imaging device 10 advances the process to step S155.

  When the process has proceeded to step S154, the imaging apparatus 10 determines the in-focus position on the near distance side (S154), and the process proceeds to step S149. On the other hand, when the process proceeds to step S155, the imaging apparatus 10 determines that the in-focus position is indefinite, and proceeds the process to step S149. In this way, any of the four patterns of attributes for the in-focus position can be determined from the in-focus state evaluation values at at least three focus positions. These at least three focus positions are set at positions that are separated by an allowable focus range (depth of field) or more in order to facilitate detection of the in-focus direction.

  The method for calculating the focus position and the focus direction has been described above.

(About focus control)
Next, focus control performed in steps S112 and S115 in FIG. 6 will be described with reference to FIGS. A characteristic part of the focus control according to the present embodiment is the wobbling operation. Therefore, the control process related to the wobbling operation will be described in detail. The focus control is realized mainly by the function of the control means 18.

(Wobbling control amount calculation method)
First, a method for calculating the wobbling control amount will be described with reference to FIG. The wobbling operation is an operation of sequentially reciprocating a position shifted toward the ∞ direction side by a predetermined amount with respect to the current reference focus position and a position shifted by a predetermined amount (control amount) toward the short distance direction side. Here, a method for calculating the control amount will be described.

  As illustrated in FIG. 9, the imaging apparatus 10 that has started the calculation of the wobbling control amount calculates the depth of field (Fδ) (S161). The depth of field Fδ can be calculated from F (aperture) × δ (permissible circle of confusion) from the shift amount on the imager. For example, δ = 15 μm. Further, the imaging apparatus 10 is assumed to hold in advance a conversion coefficient of the focus shift amount with respect to the shift amount on the imager depending on the zoom focal length. Next, the imaging apparatus 10 resets the parameter n to 1 (S162). Next, the imaging apparatus 10 determines whether the parameter n is n ≦ the number of evaluation blocks (S163). If n ≦ the number of evaluation blocks, the imaging device 10 advances the process to step S164. On the other hand, if n ≦ the number of evaluation blocks is not satisfied, the imaging device 10 advances the process to step S173.

  When the process proceeds to step S164, the imaging apparatus 10 reads out the detection result of the in-focus position and the in-focus direction from the storage unit (S164). Next, the imaging device 10 determines whether or not the in-focus position is indefinite (S165). If the in-focus position is indefinite, the imaging device 10 advances the process to step S172. On the other hand, when the in-focus position is not indefinite, the imaging device 10 advances the process to step S166. When the process has proceeded to step S166, the imaging apparatus 10 determines whether there is data on the focus deviation amount (S166). If there is focus deviation amount data, the imaging apparatus 10 advances the process to step S167. On the other hand, when there is no focus deviation amount data, the imaging apparatus 10 advances the processing to step S172.

  When the process proceeds to step S167, the imaging apparatus 10 sets the control amount to the in-focus deviation (Fδ) × 2 (S167). Next, the imaging apparatus 10 determines whether or not the control amount is control amount> 8Fδ (S168). If the control amount is greater than 8Fδ, the imaging device 10 advances the process to step S172. On the other hand, if the control amount is not greater than 8Fδ, the imaging device 10 advances the process to step S169. When the process proceeds to step S169, the imaging apparatus 10 determines whether or not the control amount is control amount <4Fδ (S169). When the control amount <4Fδ, the imaging device 10 advances the process to step S171. On the other hand, when the control amount <4Fδ is not satisfied, the imaging device 10 advances the processing to step S170.

  When the process proceeds to step S170, the imaging apparatus 10 increments the parameter n by 1 (S170), updates the evaluation target block, and returns the process to step S163. If the process proceeds to step S171 in step S169, the imaging device 10 sets the control amount to 4Fδ (S171), and the process proceeds to step S170. When the process proceeds to step S172 in step S165, S166, or S168, the imaging device 10 sets the control amount to 8Fδ (S172), and the process proceeds to step S170. When the process proceeds to step S173 in step S163, the imaging device 10 sets the final control amount to the maximum value of the control amount calculated for each block (S173), and ends the wobbling control amount calculation process.

  The method for calculating the wobbling control amount has been described above.

(Wobbling Focus drive: first control process)
Next, the first control process (Wobbling Focus drive) performed in step S112 of FIG. 6 will be described with reference to FIG.

  As shown in FIG. 10, the imaging apparatus 10 that has started wobbling focus driving calculates a wobbling control amount (XFδ) by the method shown in FIG. 9 (S181). Next, the imaging apparatus 10 determines whether or not the state parameter State is State = 0 (S182). If State = 0, the imaging apparatus 10 advances the process to step S183. On the other hand, if State = 0 is not satisfied, the imaging apparatus 10 advances the processing to step S185. When the process proceeds to step S183, the imaging apparatus 10 sets the drive direction to the ∞ direction side and sets the drive amount to XFδ (S183). Next, the imaging apparatus 10 sets the state parameter State to State = 1 (S184), and the process proceeds to step S190.

  When the process has proceeded to step S185 in step S182, the imaging device 10 determines whether State = 1 (S185). If State = 1, the imaging device 10 advances the process to step S186. On the other hand, if State = 1 is not satisfied, the imaging device 10 advances the processing to step S188. When the process has proceeded to step S186, the imaging apparatus 10 sets the drive direction to the near distance direction and sets the drive amount to 2XFδ (S186). Next, the imaging apparatus 10 sets the state parameter State to State = 2 (S187), and the process proceeds to step S190.

  If the process proceeds to step S188 in step S185, the imaging device 10 sets the drive direction to the ∞ direction side and sets the drive amount to XFδ (S188). Next, the imaging device 10 sets the state parameter State to State = 0 (S189), and the process proceeds to step S190. The imaging apparatus 10 that has proceeded to step S190 drives and controls the focus lens 113 with the set driving direction and driving amount (S190).

  For example, if the current reference focus position is 180, the aperture value is 4, and the conversion coefficient corresponding to the zoom focal length is 1/12, 8Fδ × (1/12) = 40, and the three focus positions are 140, 180, 220. In this case, the focus position is controlled in the order of 140 moved by 8Fδ from the reference focus position 180 toward the ∞ direction side and 220 moved by 8Fδ toward the short distance direction side. That is, control is performed by driving from the reference focus position by −40 pulses, then by +80 pulses, and finally by driving by −40 pulses to return to the original position.

  The first control process has been described above.

(Wobbling + MF Focus drive: second control process)
Next, the second control process (Wobbling + MF Focus drive) performed in step S115 of FIG. 6 will be described with reference to FIG.

  When there is a manual focus operation and the drive amount corresponding to the operation amount is smaller than the control width by wobbling (40 pulses in this example), the focus deviation amount necessary for detecting the in-focus state cannot be obtained. A method of controlling the drive by adding a drive amount corresponding to the operation amount to the drive amount of the wobbling control is preferable. The second control process relates to such a method.

  As illustrated in FIG. 11, the imaging apparatus 10 that has started wobbling + MF focus driving calculates a wobbling control amount (XFδ) (S201). Next, the imaging apparatus 10 calculates a manual focus drive amount (A) (S202). Next, the imaging apparatus 10 determines whether the direction of the manual focus operation is the ∞ direction side (S203). When the direction of the manual focus operation is the ∞ direction side, the imaging device 10 advances the process to step S204. On the other hand, when the direction of the manual focus operation is not the ∞ direction side, the imaging device 10 advances the process to step S213.

  When the process proceeds to step S204, the imaging device 10 determines whether or not the state parameter State is State = 0 (S204). If State = 0, the imaging apparatus 10 advances the process to step S205. On the other hand, when State = 0 is not satisfied, the imaging device 10 advances the process to step S208. When the process proceeds to step S205, the imaging apparatus 10 sets the drive direction to the ∞ direction side and sets the drive amount to XFδ + A (S205). Next, the imaging apparatus 10 sets the state parameter State to State = 1 (S206), and the process proceeds to step S207.

  When the process proceeds to step S208 in step S204, the imaging device 10 determines whether or not the state parameter State is State = 1 (S208). If State = 1, the imaging device 10 advances the process to step S209. On the other hand, when State = 1 is not satisfied, the imaging device 10 advances the processing to step S211. When the process has proceeded to step S209, the imaging device 10 sets the drive direction to the near distance direction and sets the drive amount to 2XFδ (S209). Next, the imaging apparatus 10 sets the state parameter State to State = 2 (S210), and the process proceeds to step S207.

  When the process proceeds to step S211 in step S208, the imaging device 10 sets the drive direction to the ∞ direction side and sets the drive amount to XFδ (S211). Next, the imaging apparatus 10 sets the state parameter State to State = 0 (S212), and advances the processing to Step S207.

  When the process proceeds to step S213 in step S203, the imaging device 10 determines whether or not the state parameter State is State = 0 (S213). If State = 0, the imaging apparatus 10 advances the process to step S214. On the other hand, when State = 0 is not satisfied, the imaging device 10 advances the processing to step S216. When the process proceeds to step S214, the imaging apparatus 10 sets the drive direction to the ∞ direction side and sets the drive amount to XFδ-A (S214). Next, the imaging device 10 sets the state parameter State to State = 1 (S215), and the process proceeds to step S207.

  When the process proceeds to step S216 in step S213, the imaging device 10 determines whether or not the state parameter State is State = 1 (S216). If State = 1, the imaging device 10 advances the process to step S217. On the other hand, if State = 1 is not satisfied, the imaging device 10 advances the process to step S219. When the process has proceeded to step S217, the imaging apparatus 10 sets the drive direction to the near distance direction and sets the drive amount to 2XFδ (S217). Next, the imaging apparatus 10 sets the state parameter State to State = 2 (S218), and the process proceeds to step S207.

  If the process proceeds to step S219 in step S216, the imaging device 10 sets the drive direction to the ∞ direction side and sets the drive amount to XFδ (S219). Next, the imaging apparatus 10 sets the state parameter State to State = 0 (S220), and advances the processing to Step S207. When the process proceeds to step S207 along any one of the flows described above, the imaging apparatus 10 controls the focus position with the set driving direction and driving amount (S207).

  The second control process has been described above.

(MF Focus drive: third control process)
The second control process described above is a case where the drive amount by the manual focus operation is smaller than the control width by the wobbling. On the other hand, when the driving amount by the manual focus operation is larger than the control range (for example, 40 pulses) by the wobbling, there is a high possibility that the in-focus position desired by the photographer is not near the current focus position. Further, in this case, three different focus positions sufficient for focus detection can be obtained by driving by manual focus operation without performing a wobbling operation. Therefore, in this case, the control is set to prohibit the wobbling control. In this way, by switching the focus control in accordance with the operation state, it is possible to eliminate wasteful control and realize a suitable focus control.

  The third control process has been described above.

(Such as parameter settings)
In the above description, an example is given in which the wobbling control amount is 40 pulses (8Fδ). However, the value of 40 pulses enables the in-focus focus position to be calculated even from a position sufficiently away from the in-focus focus position. The setting value is set so that the degree of focus at the current focus position can be calculated.

  Further, according to the focus control described above, when the focus focus position is once detected in the detection area of one block and the focus focus position is further approached by a manual focus operation, the focus focus is controlled with a wobbling control amount less than 8Fδ. The position can be calculated. Also, as shown in FIG. 9, when the current focus deviation is 4Fδ or less, the amount twice as large as the focus deviation is set as the wobbling control amount, so that the amount necessary for calculating the in-focus focus position can be reduced. A wobbling operation can be performed. However, since it is difficult to detect a peak if the control amount is too small, 4Fδ is set as the minimum limit amount. Further, when a plurality of blocks are used as the detection area, a suitable wobbling operation is realized by adopting the maximum control value among the wobbling control amounts calculated for each block.

  The focus control according to the present embodiment has been described above.

(About in-focus status display)
Next, the in-focus state display process performed in step S111 in FIG. 6 will be described with reference to FIG.

  As illustrated in FIG. 12, the imaging apparatus 10 that has started the display process of the in-focus position and the in-focus direction calculates the depth of field (Fδ) (S231). Next, the imaging apparatus 10 sets the parameter n to 1 (S232). Next, the imaging apparatus 10 determines whether or not n ≦ the number of evaluation blocks (S233). If n ≦ the number of evaluation blocks, the imaging device 10 advances the process to step S234. On the other hand, if n ≦ the number of evaluation blocks is not satisfied, the imaging device 10 ends the display process of the focus position and the focus direction.

  When the process proceeds to step S234, the imaging apparatus 10 reads out the detection result of the in-focus position and the in-focus direction from the storage unit (S234). Next, the imaging device 10 determines whether or not the in-focus position is indefinite (S235). If the in-focus position is indefinite, the imaging device 10 advances the process to step S245. On the other hand, when the in-focus position is not indefinite, the imaging device 10 advances the process to step S236.

  When the process proceeds to step S236, the imaging apparatus 10 determines whether there is data on the amount of focus deviation (S236). If there is data on the amount of in-focus deviation, the imaging apparatus 10 advances the process to step S237. On the other hand, when there is no data on the amount of focus deviation, the imaging device 10 advances the process to step S242.

  When the process has proceeded to step S237, the imaging apparatus 10 determines whether the in-focus degree is within the depth of field (S237). If the in-focus level is within the depth of field, the imaging device 10 advances the process to step S238. On the other hand, when the degree of focus is not within the depth of field, the imaging device 10 advances the process to step S239.

  When the process proceeds to step S238, the imaging apparatus 10 displays on the LCD 16 that the in-focus state is OK (S238). For example, when the in-focus level is within the depth of field (within the allowable in-focus range: within 1 Fδ) for the area A1 in FIG. 5, the imaging device 10 displays the area A1 in a blinking yellow display.

  When the process proceeds to step S239 in step S237, the imaging device 10 determines whether or not the in-focus direction is the ∞ direction side (S239). If the in-focus direction is the ∞ direction side, the imaging device 10 advances the process to step S240. On the other hand, when the in-focus direction is not the ∞ direction side, the imaging device 10 advances the process to step S241.

  When the process proceeds to step S240, the imaging device 10 displays on the LCD 16 that the near front pin state is set (S240). For example, when the area A2 in FIG. 5 is in the near front pin state, the imaging device 10 changes the display of the area A2 to a light cyan blinking display. On the other hand, when the process has proceeded to step S241, the imaging device 10 displays on the LCD 16 that it is in the near rear pin state (S241). For example, when the area A3 in FIG. 5 is in the near rear pin state, the imaging device 10 displays the area A3 in a light blue blinking display.

  When the process proceeds to step S242 in step S236, the imaging device 10 determines whether or not the in-focus direction is the ∞ direction side (S242). If the in-focus direction is the ∞ direction side, the imaging device 10 advances the process to step S243. On the other hand, if the in-focus direction is not the ∞ direction side, the imaging device 10 advances the process to step S244.

  When the process has proceeded to step S243, the imaging device 10 displays on the LCD 16 that the front pin state has been reached (S243). For example, when the area A2 in FIG. 5 is in the front pin state, the imaging device 10 displays the area A2 in a flashing dark cyan color. On the other hand, when the process proceeds to step S244, the imaging device 10 displays on the LCD 16 that the rear pin state is set (S244). For example, when the area A3 in FIG. 5 is in the rear pin state, the imaging device 10 displays the area A3 in a dark blue blinking display.

  If the process proceeds to step S245 in step S235, the imaging apparatus 10 does not display the in-focus state on the LCD 16 (S245), and the process proceeds to step S246. In addition, even after any of the processes in steps S240, S241, S243, and S244 is completed, the imaging device 10 advances the process to step S246. The imaging apparatus 10 that has proceeded to step S246 increments the parameter n by 1 (S246), updates the evaluation area, and returns the process to step S233.

  The in-focus state display method has been described above. In this way, by changing the display mode according to the focus state, it is possible to notify the photographer of whether or not each block is within the allowable focus range and the manual focus operation direction for focusing. Note that the expression method, such as display color and presence / absence of blinking, is not limited to the above example. Although the method for notifying the in-focus state by display has been described here, the in-focus state can be notified using sound, vibration, or the like. Furthermore, the focus ring 111 may be configured to notify the in-focus state by applying a slight rotation according to the in-focus direction.

(About validity indication of focus position and operation direction)
Next, with reference to FIG. 13, a process for displaying the validity of the in-focus position and the operation direction performed in step S113 in FIG. 6 will be described.

  As illustrated in FIG. 13, the imaging apparatus 10 that has started the process of displaying the appropriateness of the focus position and the operation direction calculates the depth of field (Fδ) (S251). Next, the imaging apparatus 10 resets the parameter n to 1 (S252). Next, the imaging apparatus 10 determines whether or not n ≦ the number of evaluation blocks (S253). If n ≦ the number of evaluation blocks, the imaging device 10 advances the process to step S254. On the other hand, if not n ≦ the number of evaluation blocks, the imaging apparatus 10 ends the process of displaying the validity of the in-focus position and the operation direction.

  When the process proceeds to step S254, the imaging apparatus 10 reads out the detection result of the in-focus position and the in-focus direction from the storage unit (S254). Next, the imaging apparatus 10 reads the direction of manual focus operation from the storage unit (S255). Next, the imaging device 10 determines whether or not the in-focus position is indefinite (S256). If the in-focus position is indefinite, the imaging device 10 advances the process to step S266. If the in-focus position is not indefinite, the imaging device 10 advances the process to step S257.

  When the process has proceeded to step S257, the imaging apparatus 10 determines whether there is data on the amount of focus deviation (S257). If there is data on the amount of in-focus deviation, the imaging apparatus 10 advances the process to step S258. On the other hand, when there is no data on the amount of focus deviation, the imaging device 10 advances the process to step S263.

  When the process has proceeded to step S258, the imaging apparatus 10 determines whether or not the focus level is within the depth of field (S258). When the in-focus level is within the depth of field, the imaging device 10 advances the process to step S259. On the other hand, when the degree of focus is not within the depth of field, the imaging device 10 advances the process to step S260.

  When the process proceeds to step S259, the imaging apparatus 10 displays on the LCD 16 that the in-focus state is OK (S259). For example, when the in-focus level is within the depth of field (within the allowable in-focus range: within 1 Fδ) for the area A1 in FIG. 5, the imaging device 10 displays the area A1 in a blinking yellow display.

  When the process has proceeded to step S260, the imaging device 10 determines whether or not the in-focus direction and the operation direction match (S260). If the in-focus direction and the operation direction match, the imaging apparatus 10 advances the process to step S261. On the other hand, when the in-focus direction and the operation direction do not match, the imaging device 10 advances the processing to step S262.

  When the process proceeds to step S261, the imaging device 10 displays on the LCD 16 that the vicinity operation direction is OK (S261). For example, when the vicinity operation direction is OK with respect to the area A2 in FIG. 5, the imaging apparatus 10 displays the area A2 in a light green blinking display. On the other hand, when the process proceeds to step S262, the imaging apparatus 10 displays on the LCD 16 that the vicinity operation direction is NG (S262). For example, when the region A3 in FIG. 5 is in the vicinity operation direction NG, the imaging device 10 displays the region A3 in a light red blinking display.

  When the process proceeds to step S263 in step S257, the imaging device 10 determines whether or not the in-focus direction and the operation direction match (S263). If the in-focus direction and the operation direction match, the imaging apparatus 10 advances the process to step S264. On the other hand, when the in-focus direction and the operation direction do not match, the imaging device 10 advances the process to step S265.

  When the process proceeds to step S264, the imaging device 10 displays on the LCD 16 that the operation direction is OK (S264). For example, when the operation direction is OK with respect to the area A2 in FIG. 5, the imaging device 10 displays the area A2 in a dark green blinking display. On the other hand, when the process proceeds to step S265, the imaging device 10 displays on the LCD 16 that the operation direction is NG (S265). For example, when the operation direction is NG with respect to the area A3 in FIG. 5, the imaging device 10 displays the area A3 in a flashing dark red color.

  If the process proceeds to step S266 in step S256, the imaging apparatus 10 does not display the focus state and the validity of the operation direction on the LCD 16 (S266), and the process proceeds to step S267. In addition, even after any of the processes in steps S261, S262, S264, and S265 is completed, the imaging device 10 advances the process to step S267. The imaging apparatus 10 that has proceeded to step S267 increments the parameter n by 1 (S267), updates the evaluation area, and returns the process to step S253.

  The display method related to the validity of the focused state and the operation direction has been described above. In this way, by changing the display form in accordance with the focus state and the validity of the operation direction, it is possible to notify the photographer whether the manual focus operation direction is toward in-focus. Note that the expression method, such as display color and presence / absence of blinking, is not limited to the above example. Although the method for notifying the in-focus state by display has been described here, the in-focus state can be notified using sound, vibration, or the like. Furthermore, the focus ring 111 may be configured to notify the in-focus state by applying a slight rotation according to the in-focus direction.

(Other)
In the above description, an example is shown in which each block of a small block group divided into 30 × 18 is displayed independently, but any one block designated by the photographer may be set as an evaluation target block. In the above description, six patterns of display modes are exemplified. However, the degree of focus may be further finely classified, and the display may be finer according to the number of classifications. In the above description, three focus positions are used, but four or more focus positions may be used. Such a modification naturally belongs to the technical scope of the present embodiment.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

DESCRIPTION OF SYMBOLS 10 Imaging device 11 Imaging optical system 111 Zoom ring 112 Aperture 113 Focus lens 114 Zoom lens 115 Focus ring 12 Image sensor 13 Image signal processing circuit 131 Focus state evaluation value calculation means 132 Display image composition means 14 VRAM
15 LCD driver 16 LCD
17 Memory 18 Control means (CPU)
181 Zoom focal length calculation means 182 Focus one detection means 183 Focus distance calculation means 184 Manual focus operation state detection means 185 In-focus position / direction calculation means 186 Focus drive control means 19 Operation member 20 Timing generator 21 Focus drive means 22 Aperture drive means

Claims (16)

In-focus evaluation means for detecting an in-focus state from captured images at a plurality of different focus positions and calculating an in-focus focus position and an in-focus vicinity degree;
A state detection means for detecting a manual focus operation state of the photographer;
Have
The focus control for detecting the in-focus state is varied according to the in-focus vicinity degree calculated by the in-focus evaluation unit and the manual focus operation state detected by the state detection unit. apparatus. A focus control means for performing the focus control;
The focus control unit periodically causes the focus lens to perform a wobbling operation when the rotational movement amount of the focus ring falls below a predetermined threshold value, and when the rotational movement amount of the focus ring exceeds a predetermined threshold value, the focus lens The imaging apparatus according to claim 1, wherein no wobbling operation is performed. The imaging apparatus according to claim 1, wherein the focus control unit causes the focus lens to perform a wobbling operation with a movement amount determined in accordance with at least an aperture value and a degree of in-focus proximity. The imaging apparatus according to claim 1, wherein the focus control unit does not perform a wobbling operation of the focus lens when a zooming operation is performed. The imaging apparatus according to any one of claims 1 to 4, further comprising information display means for displaying information indicating the degree of in-focus proximity on a screen. The imaging apparatus according to claim 5, wherein the information display unit does not display information on the in-focus vicinity degree on a screen when a zooming operation is performed. The focus evaluation unit detects the degree of focus vicinity for each of a plurality of divided imaging regions,
The imaging apparatus according to claim 5, wherein the information display unit displays information indicating a degree of focus proximity detected for each imaging area in a screen area corresponding to each imaging area. The imaging apparatus according to claim 7, wherein the information display unit emphasizes display of a screen area corresponding to the focused imaging area. A focus evaluation step of detecting a focus state from captured images at a plurality of different focus positions, and calculating a focus focus position and a focus vicinity degree;
A state detection process for detecting the manual focus operation state of the photographer;
Including
The focus control for detecting the in-focus state is made different according to the in-focus vicinity degree calculated in the in-focus evaluation step and the manual focus operation state detected in the state detection step. Control method in the apparatus. A focus control step of performing the focus control;
In the focus control step, when the rotational movement amount of the focus ring falls below a predetermined threshold, the focus lens is periodically wobbling, and when the rotational movement amount of the focus ring exceeds a predetermined threshold, the focus lens The control method in the imaging apparatus according to claim 9, wherein the wobbling operation is not performed. The control method for an imaging apparatus according to claim 9 or 10, wherein, in the focus control step, the focus lens is wobbled with a movement amount determined according to at least an aperture value and the focus degree. . The control method for an imaging apparatus according to any one of claims 9 to 11, wherein, in the focus control step, the focus lens is not wobbled when a zooming operation is performed. The control method in the imaging apparatus according to claim 9, further comprising an information display step of displaying information indicating the degree of near focus on a screen. 14. The control method for an imaging apparatus according to claim 13, wherein, in the information display step, when the zooming operation is performed, information on the degree of near focus is not displayed on the screen. In the focus evaluation step, the degree of focus vicinity is detected for each of the plurality of divided imaging regions,
The control method in the imaging apparatus according to claim 13 or 14, wherein, in the information display step, information indicating a degree of in-focus proximity detected for each imaging area is displayed on a screen area corresponding to each imaging area. The control method in the imaging apparatus according to claim 15, wherein in the information display step, display of a screen area corresponding to the focused imaging area is emphasized.

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