Imaging apparatus

Abstract

To provide an imaging apparatus that can quickly detect a subject after switching of the photographing direction is completed and smoothly transition to photographing.SOLUTION: An imaging apparatus includes imaging means that outputs an imaging signal corresponding to an optical image formed by an optical system, driving means that can change the shooting direction of the imaging means, and control means that controls the aperture position of an aperture included in the optical system, and the control means can change the aperture position to a predetermined position in response to the start of a change in the shooting direction.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to an imaging device. [Background technology]

[0002] An imaging device with an imaging unit mounted on a gimbal that can rotate in pan / tilt / roll directions can capture images while suppressing camera shake. This type of imaging device can be switched between a selfie mode and a non-selfie mode while the photographer is holding the gimbal by, for example, rotating the pan axis to change the orientation of the imaging unit (switching the shooting orientation). In addition, in the selfie mode, the imaging unit can automatically track the direction of the subject, keeping the subject near the center of the angle of view.

[0003] Since the state of the subject changes suddenly when the shooting direction is changed, it is preferable to quickly detect the subject and adjust the focus in response to the change in the subject in order to smoothly transition to shooting after changing the shooting direction. Also, it is desirable to quickly detect the subject after switching to selfie mode and automatically adjust the orientation of the imaging unit to track the direction of the subject.

[0004] Patent Document 1 proposes a configuration in which the angular velocity of at least one of the three axial directions of the gimbal is acquired, and autofocus (AF) is performed when the angular velocity remains below a predetermined value for a predetermined period of time. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2020-003730 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the configuration of Patent Document 1, when the gimbal axis is rotated to switch the shooting orientation, it is not possible to speed up focus adjustment after switching the shooting orientation. Furthermore, since the state of the next subject to be photographed cannot be accurately determined until the switching of the shooting orientation is complete, even if AF is performed while switching the shooting orientation, the desired focus adjustment state may not be achieved after the switch, making it difficult to transition to shooting smoothly. Furthermore, after switching the shooting orientation, the subject is out of focus, making it impossible to correctly detect the subject, and it is therefore impossible to perform focus adjustment on the subject. Furthermore, after switching the shooting orientation, the subject is not properly exposed, making it impossible to correctly detect the subject, and it is therefore impossible to perform focus adjustment on the subject.

[0007] An object of the present invention is to provide an imaging device that can quickly detect a subject after switching of the imaging direction is completed and smoothly transition to imaging. [Means for solving the problem]

[0008] An imaging device according to one aspect of the present invention comprises an imaging means that outputs an imaging signal corresponding to an optical image formed by an optical system, a driving means that can change the shooting direction of the imaging means, and a control means that controls the aperture position of an aperture included in the optical system, wherein the control means is capable of changing the aperture position to a predetermined position in response to the start of a change in the shooting direction. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide an imaging device that can quickly detect a subject after switching of the shooting direction is completed and smoothly transition to shooting. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a configuration diagram of an imaging device according to a first embodiment. [Figure 2] FIG. 2 is an explanatory diagram of a pixel according to the first embodiment. [Figure 3] FIG. 10 is a diagram showing a shooting state when the shooting direction is changed. [Figure 4] 5 is a flowchart showing a video shooting process according to the first embodiment. [Figure 5] 10 is a flowchart showing a shooting orientation state setting process according to the first embodiment. [Figure 6] 5 is a flowchart showing aperture drive control processing according to the first embodiment. [Figure 7] 6 is a flowchart showing aperture drive determination processing according to the first embodiment. [Figure 8] 5 is a flowchart showing an AF control process according to the first embodiment. [Figure 9] 5 is a flowchart showing a subject tracking control process according to the first embodiment. [Figure 10] 10A and 10B are diagrams illustrating states in a time series when the imaging direction is changed in a conventional example. [Figure 11] 10A to 10C are diagrams illustrating states in a time series when the shooting direction is changed according to the first embodiment. [Figure 12] FIG. 10 is a configuration diagram of an imaging device according to a second embodiment. [Figure 13] 10 is a flowchart showing a video shooting process according to the second embodiment. [Figure 14] 10 is a flowchart showing an exposure control process according to a second embodiment. [Figure 15] FIG. 10 is a configuration diagram of an imaging device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same components, and redundant explanations will be omitted. [First embodiment] (Configuration of imaging device) FIG. 1 is a diagram showing the configuration of a digital camera, which is an example of an imaging device according to this embodiment. The digital camera according to this embodiment is a lens-integrated camera, and has a lens unit 10 and a camera unit 20, which are imaging optical systems. The digital camera according to this embodiment is also a gimbal-integrated camera, and the lens unit 10 and the camera unit 20 are mounted on a gimbal unit 30. Note that in this embodiment, the digital camera is a gimbal-integrated camera that includes the gimbal unit 30 held by the photographer, but the present invention is not limited to this. The present invention can also be applied to imaging devices that are not held by the photographer, such as network cameras or broadcast cameras equipped with a rotation mechanism.

[0012] Lens unit 10 has an optical system and a drive / control system. The optical system includes a first lens group 101, an aperture 102, a second lens group 103, and a focus lens group (hereinafter referred to as a focus lens) 104. Thus, lens unit 10 includes focus lens 104 and is a photographic lens that forms an optical image of a subject.

[0013] The first lens group 101 is disposed at the tip (closest to the object) of the lens unit 10 and is held so as to be movable in the optical axis direction. The diaphragm 102 has the function of adjusting the amount of light during shooting. The diaphragm 102 and the second lens group 103 are movable together in the optical axis direction, and achieve a zoom function by moving in conjunction with the first lens group 101. The focus lens 104 is movable in the optical axis direction, and the subject distance (focusing distance) at which the lens unit 10 focuses changes depending on the position. Focus adjustment, which adjusts the focusing distance of the lens unit 10, is performed by controlling the position of the focus lens 104 in the optical axis direction.

[0014] The drive / control system includes a zoom actuator 105, an aperture actuator 106, and a focus actuator 107. The drive / control system also includes a zoom drive circuit 108, an aperture drive circuit 109, a focus drive circuit 110, and a lens control unit 111. The zoom drive circuit 108 drives the first lens group 101 and the third lens group 103 in the optical axis direction using the zoom actuator 105, thereby controlling the angle of view of the optical system of the lens unit 10. The aperture drive circuit 109 drives the aperture 102 using the aperture actuator 106, thereby controlling the aperture diameter and opening / closing operation of the aperture 102. The focus drive circuit 110 drives the focus lens 104 in the optical axis direction using the focus actuator 107, thereby changing the focal length of the optical system of the lens unit 10. The focus drive circuit 110 also detects the current position of the focus lens 104 using the focus actuator 107.

[0015] The lens control unit 111 controls the zoom driving circuit 108, the aperture driving circuit 109, and the focus driving circuit 110. The lens control unit 111 also communicates with the camera control unit 204. For example, the lens control unit 111 acquires the position of the focus lens 104 and notifies the camera control unit 204 of the focus lens position information. Furthermore, the lens control unit 111 controls the zoom driving circuit 108, the aperture driving circuit 109, and the focus driving circuit 110 in accordance with a processing command from the camera control unit 204.

[0016] The camera unit 20 includes an image sensor 201 , an image sensor drive circuit 202 , an image processing circuit 203 , a camera control unit (control means) 204 , a contrast focus detection unit 205 , and a subject detection unit 206 .

[0017] The image sensor 201 is composed of a CMOS image sensor and peripheral circuits. The image sensor 201 has m horizontal and n vertical pixels (m and n are integers equal to or greater than 2). FIG. 2(a) shows an example of the pixel arrangement of the image sensor 201, depicting a six-row (Y direction) and eight-column (X direction) area of ​​a two-dimensional CMOS area sensor, as viewed from the lens unit 10 side. The image sensor 201 is provided with color filters in a Bayer array. Red (R) and green (G) color filters are alternately arranged from left to right on the odd-numbered rows of pixels, and green (G) and blue (B) color filters are alternately arranged from left to right on the even-numbered rows of pixels. The pixel 211R will be described with reference to FIG. 2(b). Circles 211i represent on-chip microlenses, and rectangles 211X arranged inside the on-chip microlenses are photoelectric conversion units. The pixels 211Gr, 211Gb, and 211B have the same configuration.

[0018] The image sensor drive circuit 202 controls the operation of the image sensor 201 , and also performs A / D conversion on the acquired image signal and transmits it to the camera control unit 204 .

[0019] The image processing circuit 203 generates contrast AF data and display / record image data from the image data output by the image sensor 201. The image processing circuit 203 also performs general image processing performed in digital cameras, such as gamma conversion, white balance adjustment, color interpolation, and compression encoding, on the image data output by the image sensor 201.

[0020] The camera control unit 204 controls the entire digital camera. The camera control unit 204 includes a ROM 204a, a RAM 204b, and an EEPROM 204c. The ROM (Read Only Memory) 204a stores programs that control camera operation. The RAM (Random Access Memory) 204b stores variables. The EEPROM (Electrically Erasable Programmable Read-Only Memory) 204c stores various parameters and various setting information for the camera unit 20 set by the user.

[0021] The camera control unit 204 issues instructions (requests) to the lens control unit 111, such as a request to acquire the focus lens position, a request to drive the aperture, a request to drive the focus, a request to drive the zoom, and a request to acquire optical information specific to the lens unit 10. The camera control unit 204 also receives processing commands from the user at the operation unit 303 via the gimbal control unit 301 of the gimbal unit 30, in order to change the operation of the image sensor drive circuit 202 and the image processing circuit 203. Furthermore, the camera control unit 204 displays an imaging signal on a display unit 302 and records the imaging signal in a memory 304 via the gimbal control unit 301.

[0022] The contrast focus detection unit 205 performs focus detection processing using signal data obtained by the image processing circuit 203. The contrast focus detection unit 205 generates a focus signal by extracting specific frequency components from the luminance signal generated by the image processing circuit 203 through a band-pass filter (BPF). The contrast focus detection unit 205 also detects line peak values ​​for each horizontal line within a predetermined imaging range from the focus signal. The contrast focus detection unit 205 then vertically integrates the line peak values ​​for each horizontal line within the predetermined imaging range to generate an integral evaluation value. The camera control unit 204 performs autofocus (AF) by adjusting the position of the focus lens 104 via the lens control unit 111 so as to search for a peak position where the integral evaluation value is largest. Note that, although focus detection is performed by contrast focus detection in this embodiment, the present invention is not limited to this. Focus detection may also be performed by image-plane phase difference detection using an image sensor with a pupil division function.

[0023] The subject detection unit 206 performs subject detection based on image data obtained by the image processing circuit 203. In this embodiment, subject detection, which estimates the position of the target subject in the image data, is used to select the focus adjustment result of the contrast focus detection unit 205 so that the camera control unit 204 can drive the focus lens 104 via the lens control unit 111. The subject to be detected is, for example, a person's face and the pupils contained therein, an animal's body and the face / pupils contained therein, or the entire vehicle and characteristic parts contained therein (such as the driver or cockpit of the vehicle). In addition, a subject present at a position specified by the user on the captured image screen is detected via a user's touch operation on the display 302, etc.

[0024] The gimbal unit 30 has a gimbal control unit 301, a display 302, an operation unit 303, a memory 304, an inertial measurement device 305, a yaw axis rotation mechanism 306, a pitch axis rotation mechanism 307, and a roll axis rotation mechanism 308. The gimbal unit 30 is configured to be drivable to rotate in at least one of a pan direction and a tilt direction in order to change the shooting direction of the image sensor 201.

[0025] The gimbal control unit 301 controls the operation of each unit of the gimbal unit 30. The gimbal control unit 301 exchanges information with the camera control unit 204, provides information to change the operation of the image sensor drive circuit 202 and the image processing circuit 203, and performs display on the display unit 302 and recording in the memory 304 based on the image pickup signal from the camera control unit 204. The gimbal control unit 301 also controls the zoom drive circuit 108, the aperture drive circuit 109, and the focus drive circuit 110 via the camera control unit 204.

[0026] The display 302 is composed of an LCD (liquid crystal display) or the like, and displays information about the shooting mode, a preview image before shooting, a confirmation image after shooting, an in-focus state display image during focus detection, etc. The display 302 has a touch operation function, and it is possible to operate the digital camera by directly touching the display 302, for example.

[0027] The operation unit 303 includes a power switch, a focus adjustment start switch, a shooting trigger switch, a zoom operation switch, and a gimbal operation switch. The memory 304 is a removable flash memory that records captured images. The inertial measurement unit 305 includes an acceleration sensor and a gyro sensor, and detects the acceleration of the entire digital camera in three axes: forward / backward, left / right, and up / down. It also detects angular velocity in three axes: the yaw axis, pitch axis, and roll axis.

[0028] The yaw axis rotation mechanism 306 includes a yaw axis motor that can rotate the lens unit 10 and the camera unit 20 in the yaw axis direction. The pitch axis rotation mechanism 307 includes a pitch axis motor that can rotate the lens unit 10 and the camera unit 20 in the pitch axis direction. The roll axis rotation mechanism 308 includes a roll axis motor that can rotate the lens unit 10 and the camera unit 20 in the roll axis direction.

[0029] The gimbal control unit 301 controls the yaw axis rotation mechanism 306, the pitch axis rotation mechanism 307, and the roll axis rotation mechanism 308 to suppress camera shake during shooting. When the photographer issues a drive command for the yaw axis rotation mechanism 306, the pitch axis rotation mechanism 307, and the roll axis rotation mechanism 308 using the gimbal operation switch on the operation unit 303, the gimbal control unit 301 performs control in accordance with the command. The gimbal control unit 301 also controls the yaw axis rotation mechanism 306, the pitch axis rotation mechanism 307, and the roll axis rotation mechanism 308 to frame the subject detected by the subject detection unit 206 so that it fits within the imaging screen. In this embodiment, as shown in FIG. 3 , the yaw axis rotation mechanism 306 or the pitch axis rotation mechanism 307 is controlled using an operation on the operation unit 303 or the display 302 as a trigger, thereby changing the shooting orientation while the photographer is still holding the digital camera. For example, in Fig. 3(a), the photographer is photographing a distant subject A in a photographing direction A. In the state of Fig. 3(a), the photographer can rotate the yaw axis rotation mechanism 306 by operating the operation unit 303 or the display 302, and switch the photographing orientation to a photographing direction B of the photographer (subject B) while holding the digital camera device, as shown in Fig. 3(b). Methods for changing the photographing orientation include, for example, pressing a photographing orientation switch button on the operation unit 303 or touching a photographing orientation switch icon on the touch panel of the display 302, but other methods may also be used. (Details of various processes performed by the camera unit 20) 4 is a flowchart showing video shooting processing executed by the camera control unit 204 in accordance with an imaging processing program, which is a computer program. "S" indicates a step. The camera control unit 204 executes various video shooting controls and AF controls by repeatedly performing video shooting processing. Note that, although only video shooting processing will be described in this embodiment, a similar method may also be used for still image shooting processing.

[0030] In S401, the camera control unit 204 determines whether or not an instruction to start video shooting (hereinafter referred to as a video shooting instruction) has been input by touching the operation unit 303 or the display 302 via the gimbal control unit 301. The video shooting instruction is notified when the video shooting switch on the operation unit 303 is pressed while video shooting is not in progress, or when the video shooting icon on the display 302 is pressed. If the camera control unit 204 determines that a video shooting instruction has been input, it executes the processing of S402, and if it determines that a video shooting instruction has not been input, it executes the processing of S403.

[0031] In S402 , the camera control unit 204 performs video shooting processing and records the video images in the memory 304 via the gimbal control unit 301 .

[0032] In S403, the camera control unit 204 determines whether or not a moving image is being captured. If the camera control unit 204 determines that a moving image is being captured, it executes the process of S404, and if it determines that a moving image is not being captured, it executes the process of S406.

[0033] In S404, the camera control unit 204 determines whether or not an instruction to stop video shooting (hereinafter referred to as a video shooting stop instruction) has been input by a touch operation on the operation unit 303 or the display 302 via the gimbal control unit 301. The instruction to stop video shooting is notified when the video shooting switch on the operation unit 303 is pressed or the video shooting icon on the display 302 is pressed during video shooting. If the camera control unit 204 determines that an instruction to stop video shooting has been notified, it executes the process of S405, and if it determines that an instruction to stop video shooting has not been notified, it executes the process of S402.

[0034] In S405, the camera control unit 204 performs a process to stop video shooting via the gimbal control unit 301, and stops recording of video images in the memory 304.

[0035] In S406, the camera control unit 204 performs a shooting orientation state setting process.

[0036] In S407, the camera control unit 204 performs aperture drive control processing.

[0037] In S408, the camera control unit 204 performs AF control processing.

[0038] In S409, the camera control unit 204 performs subject tracking control processing.

[0039] The shooting orientation state setting process performed by the camera control unit 204 in S406 of Fig. 4 will be described below with reference to Fig. 5. Fig. 5 is a flowchart showing the shooting orientation state setting process.

[0040] In S501, the camera control unit 204 determines whether the shooting orientation is currently being changed. The shooting orientation is currently being changed when the gimbal control unit 301 rotates the yaw axis rotation mechanism 306 or the pitch axis rotation mechanism 307 to change the shooting orientation. For example, this is a state in which the shooting orientation is currently being changed from the state shown in FIG. 3(a) to the state shown in FIG. 3(b), or from the state shown in FIG. 3(b) to the state shown in FIG. 3(a). If the camera control unit 204 determines that the shooting orientation is currently being changed, it executes the process of S505. If it determines that the shooting orientation is not currently being changed, it executes the process of S502. Note that the following description will basically focus on a configuration that rotates the yaw axis rotation mechanism 306, but this may be replaced with a configuration that rotates the pitch axis rotation mechanism 307.

[0041] In S502, the camera control unit 204 determines whether or not there is an instruction to change the shooting orientation. The instruction to change the shooting orientation can be issued, for example, by pressing a shooting orientation switch button on the operation unit 303 or by touching a shooting orientation switch icon on the touch panel of the display 302. If the camera control unit 204 determines that there is an instruction to change the shooting orientation, it executes the process of S504, and if it determines that there is not an instruction to change the shooting orientation, it executes the process of S503.

[0042] In S503, the camera control unit 204 sets the shooting direction to a no-change state.

[0043] In S504, the camera control unit 204 starts switching the shooting direction.

[0044] In S505, the camera control unit 204 determines whether the change in the shooting direction has been completed. If the camera control unit 204 determines that the change in the shooting direction has been completed, it executes the process of S507, and if it determines that the change in the shooting direction has not been completed, it executes the process of S506.

[0045] In S506, the camera control unit 204 sets the imaging direction to a changing state.

[0046] In S507, the camera control unit 204 sets the imaging direction change completion state.

[0047] The aperture drive control process performed by the camera control unit 204 in S407 of Fig. 4 will be described below with reference to Fig. 6. Fig. 6 is a flowchart showing the aperture drive control process.

[0048] In S601, the camera control unit 204 determines whether the imaging direction is being changed. If the camera control unit 204 determines that the imaging direction is being changed, it executes the process of S602, and if it determines that the imaging direction is not being changed, it ends this flow.

[0049] In S602, the camera control unit 204 determines whether the shooting direction after switching is toward the photographer (toward the photographer). For example, as shown in FIG. 3(b), the camera control unit 204 can determine whether the shooting direction is toward the photographer based on whether the shooting direction is the same as the direction toward the display 302. If the camera control unit 204 determines that the shooting direction is toward the photographer, it executes the process of S603, and if it determines that the shooting direction is not toward the photographer, it ends this flow.

[0050] In S603, the camera control unit 204 performs aperture drive determination processing.

[0051] In S604, the camera control unit 204 determines whether the aperture drive determination result of the aperture drive determination process executed in S603 is TRUE. If the camera control unit 204 determines that the aperture drive determination result is TRUE, it executes the process of S605, and if it determines that the aperture drive determination result is not TRUE, it ends this flow.

[0052] In S605, the camera control unit 204 outputs an instruction to drive the diaphragm to the lens control unit 111. The diaphragm drive circuit 109 drives the diaphragm using the diaphragm actuator , and controls the aperture diameter and opening / closing operation of the diaphragm .

[0053] The aperture drive determination process performed by the camera control unit 204 in S603 of Fig. 6 will be described below with reference to Fig. 7. Fig. 7 is a flowchart showing the aperture drive determination process.

[0054] In S701, the camera control unit 204 determines whether the current aperture position BeforeAv is more open than a predetermined aperture position (predetermined position) Av_TH. The aperture position Av_TH is an aperture position for deepening the depth of field when the shooting direction is toward the photographer. A deeper depth of field reduces the amount of blur of the subject and increases the likelihood of detecting the subject after changing the shooting direction. When the shooting direction is toward the photographer, there is a high probability that the photographer will be photographed and the focus lens position is likely to be capable of focusing on a subject distance of approximately the person's arm's length. For example, the aperture position Av_TH can be determined based on the amount of change in the distance direction from the depth of field when the subject distance is assumed to be 1 meter. If the camera control unit 204 determines that the current aperture position BeforeAv is more open than the aperture position Av_TH, it executes the process of S702. If it determines that the current aperture position BeforeAv is not more open than the aperture position Av_TH, it executes the process of S706.

[0055] In S702, the camera control unit 204 determines whether the difference between the aperture positions BeforeAv and Av_TH is greater than a predetermined amount. If the difference is greater than the predetermined amount, the camera control unit 204 executes the process of S703, and if the difference is less than the predetermined amount, the camera control unit 204 executes the process of S706. Note that if the difference is equal to the predetermined amount, it is possible to arbitrarily set which process to execute.

[0056] In S703, the camera control unit 204 determines whether the ISO sensitivity is smaller than a predetermined value when the aperture position is changed to aperture position Av_TH. Here, if the ISO sensitivity is increased to achieve optimal exposure when the aperture is stopped down to aperture position Av_TH, the S / N ratio will deteriorate, so the ISO sensitivity is controlled so as not to exceed the predetermined value. If the ISO sensitivity is smaller than the predetermined value, the camera control unit 204 executes the process of S704, and if the ISO sensitivity is greater than the predetermined value, the camera control unit 204 executes the process of S706. Note that if the ISO sensitivity is equal to the predetermined value, it is possible to arbitrarily set which process to execute.

[0057] In S704, the camera control unit 204 determines whether the shutter speed is shorter than a predetermined value when the aperture position is changed to aperture position Av_TH. Here, by changing the shutter speed to a shorter second side to achieve an appropriate exposure state when the aperture position is narrowed to Av_TH, a decrease in frame rate and the occurrence of subject blur are suppressed. If the camera control unit 204 determines that the shutter speed is shorter than the predetermined value, it executes the process of S705, and if it determines that the shutter speed is longer than the predetermined value, it executes the process of S706. Note that when the shutter speed is equal to the predetermined value, it is possible to arbitrarily set which process to execute.

[0058] In S705, the camera control unit 204 sets the aperture drive determination result to TRUE.

[0059] In S706, the camera control unit 204 sets the aperture drive determination result to FALSE.

[0060] The AF control process performed by the camera control unit 204 in S408 of Fig. 4 will be described below with reference to Fig. 8. Fig. 8 is a flowchart showing the AF control process.

[0061] In S801, the camera control unit 204 performs subject detection processing.

[0062] In S802, the camera control unit 204 performs AF area setting processing. In the AF area setting processing, it sets the position of the subject within the imaging screen to be AFed. If the subject detection unit 206 has detected a subject, it sets the AF area based on the position and size of the detected subject, and updates the AF area when the position or size of the detected subject changes. If the subject detection unit 206 has not detected a subject, the user sets a fixed AF area or sets multiple AF areas within the screen using the operation unit 303 or display 302.

[0063] In S803, the camera control unit 204 causes the contrast focus detection unit 205 to perform focus detection.

[0064] In S804, the camera control unit 204 determines whether the imaging direction is being changed. If the camera control unit 204 determines that the imaging direction is being changed, it executes the process of S805, and if it determines that the imaging direction is not being changed, it executes the process of S806.

[0065] In S805, the camera control unit 204 stops the focus lens 104.

[0066] In S806, the camera control unit 204 determines whether the shooting orientation change is complete. If the camera control unit 204 determines that the shooting orientation change is complete, it executes the process of S807. If the camera control unit 204 determines that the shooting orientation change is not complete, i.e., that the shooting orientation is not changed, it executes the process of S809.

[0067] In S807, the camera control unit 204 changes the shooting direction to a no-change state.

[0068] In S808, the camera control unit 204 executes high-speed AF processing, which is a focusing process that prioritizes achieving focus as quickly as possible.

[0069] In S809, the camera control unit 204 determines whether or not high-speed AF processing is being executed. If the camera control unit 204 determines that high-speed AF processing is being executed, it executes the processing of S808, and if it determines that high-speed AF processing is not being executed, it executes the processing of S810.

[0070] In S810, if the aperture is driven to a position other than the aperture position BeforeAv before the change, the camera control unit 204 controls the aperture to return to the aperture position BeforeAv. If the execution of high-speed AF processing has been completed, the subject is sufficiently in focus, so there is a high possibility that the subject can be detected even if the aperture is returned to the original state.

[0071] In S811, the camera control unit 204 executes continuous AF processing. In continuous AF processing, unnecessary focusing movement is suppressed and focusing is not performed at too high a speed, assuming that recording may occur during video shooting.

[0072] The subject tracking control process performed by the camera control unit 204 in S409 of Fig. 4 will be described below with reference to Fig. 9. Fig. 9 is a flowchart showing the subject tracking control process.

[0073] In S901, the camera control unit 204 determines whether or not the imaging direction is being changed. If the camera control unit 204 determines that the imaging direction is being changed, it executes the process of S906, and if it determines that the imaging direction is not being changed, it executes the process of S902.

[0074] In S902, the camera control unit 204 determines whether the shooting direction is toward the photographer. If the camera control unit 204 determines that the shooting direction is toward the photographer, it executes the process of S903, and if it determines that the shooting direction is not toward the photographer, it executes the process of S906.

[0075] In S903, the camera control unit 204 determines whether or not the transition to continuous AF processing has been completed. If the camera control unit 204 determines that the transition to continuous AF processing has been completed, it executes the processing of S904, and if it determines that the transition to continuous AF processing has not been completed, it executes the processing of S906. The fact that the transition to continuous AF processing has been completed means that the subject is in focus, and the state is suitable for detecting the subject and starting tracking of the subject.

[0076] In S904, the camera control unit 204 determines whether or not the subject is detected. If the camera control unit 204 determines that the subject is detected, it executes the process of S905, and if it determines that the subject is not detected, it executes the process of S906.

[0077] In S905, the camera control unit 204 starts subject tracking control.

[0078] In S906, the camera control unit 204 stops subject tracking control.

[0079] In subject tracking control, the gimbal control unit 301 controls the yaw axis rotation mechanism 306, pitch axis rotation mechanism 307, and roll axis rotation mechanism 308 to frame the subject detected by the subject detection unit 206 so that it is placed in the center of the imaging screen or maintained at a predetermined fixed position.

[0080] Here, we will explain the issues with AF when the shooting direction is changed. In FIG. 3, when switching from shooting direction A to shooting direction B, and when switching from shooting direction B to shooting direction A, the subject being photographed changes in both cases. In particular, if a large change in subject distance occurs due to the switching, the focus lens 104 must also move in accordance with the change in subject distance, otherwise the focus will become blurred after the shooting direction is switched. However, when performing AF based on the image signal from the image sensor 201, the subject and subject distance after the shooting direction is switched cannot be detected until the shooting direction is switched. In other words, in order to perform AF on the subject after the shooting direction is switched, it is necessary to wait for the shooting direction to be switched. It is preferable to detect the subject and bring it into focus as soon as possible after switching the shooting direction, so that the photographer can immediately move on to shooting.

[0081] FIG. 10 is a diagram showing a time-series state when the shooting orientation is changed in a conventional example. The shooting orientations X and Y may be replaced with either the shooting orientations A and B in FIG. 3 . That is, the shooting orientations X and Y in FIG. 10 may be either the shooting orientations A and B or the shooting orientations B and A. In the shooting orientation X state, an operation to start switching the shooting orientation is triggered, and the gimbal unit control state changes over time from "shooting orientation switching in progress (rotating on the yaw axis)" to "shooting orientation switching completed," and then to the shooting orientation Y state. From the start of switching the shooting orientation to the completion of switching, the focus lens drive control state is in a focus lens stopped state, and after the shooting orientation switching is completed, it is in a high-speed AF state. In this case, at the completion of switching from the shooting orientation X to the shooting orientation Y, the focus lens position is the in-focus focus lens position in the shooting orientation X before the shooting orientation switching. That is, it is assumed that the focus lens position is located far from the in-focus focus lens position in the shooting orientation Y, and the subject captured in the shooting orientation Y is significantly blurred. If the subject is significantly blurred, there is a high possibility that the subject will not be detected, which results in a delay in starting the subject tracking operation.

[0082] 11 is a diagram showing the state of each time series when the shooting direction is changed in this embodiment. Unlike FIG. 10, in FIG. 11, the aperture state is driven to aperture position Av_TH in shooting direction Y immediately after the start of the shooting direction change. As a result, the subject detection state is reached at the timing when the shooting direction change is completed, and subject tracking control can be started. This allows the photographer to transition to shooting in a shorter time when the shooting direction change is performed.

[0083] As described above, according to the configuration of this embodiment, in the function for switching the shooting orientation, the start of switching the shooting orientation triggers the diaphragm to be driven until the diaphragm position reaches a predetermined position. The predetermined position is determined based on the subject distance that is likely to be photographed after the shooting orientation is switched. After that, once the switching of the shooting orientation is completed and the subject is detected, and an AF is enabled, control is performed to perform subject tracking and AF drive. This allows the subject to be detected more quickly after the shooting orientation is switched when the shooting orientation switching function is executed, enabling the photographer to begin shooting more quickly. [Second embodiment] In this embodiment, only the configuration that is different from the first embodiment will be described, and a description of the similar configuration will be omitted. (Configuration of imaging device) 12 is a diagram showing the configuration of a digital camera, which is an example of an imaging device according to this embodiment. In this embodiment, the camera unit 20 includes a frontlight / backlight determination unit 207 in addition to the configuration of the first embodiment. The frontlight / backlight determination unit 207 uses signal data obtained by the image processing circuit 203 to determine whether the subject has been photographed in a frontlight or backlight environment. The frontlight / backlight determination unit 207 may make the determination by referring to the luminance distribution for each region within the imaging range and a backlight determination table, or may make the determination using another method. (Details of various processes performed by the camera unit 20) 13 is a flowchart showing video shooting processing executed by the camera control unit 204 in accordance with an imaging processing program, which is a computer program. "S" indicates a step. The camera control unit 204 executes various video shooting controls, exposure control, and AF control by repeatedly performing video shooting processing. Note that, although only video shooting processing will be described in this embodiment, a similar method may also be used for still image shooting processing.

[0084] The processes of S1301 to S1306 and S1308 to S1309 are similar to the processes of S401 to S406 and S408 to S409 in FIG. 4, respectively, and therefore will not be described in detail.

[0085] In S1307, the camera control unit 204 performs exposure control processing.

[0086] The exposure control process performed by the camera control unit 204 in S1307 of Fig. 13 will be described below with reference to Fig. 14. Fig. 14 is a flowchart showing the exposure control process.

[0087] In S1401, the camera control unit 204 determines whether the shooting orientation is currently being changed. The shooting orientation is currently being changed when the gimbal control unit 301 rotates the yaw axis rotation mechanism 306 or the pitch axis rotation mechanism 307 to change the shooting orientation. For example, this is a state in which the shooting orientation is currently being changed from the state of FIG. 3(a) to the state of FIG. 3(b), or from the state of FIG. 3(b) to the state of FIG. 3(a). If the camera control unit 204 determines that the shooting orientation is currently being changed, it executes the process of S1403; if it determines that the shooting orientation is not currently being changed, it executes the process of S1402.

[0088] In S1402, the camera control unit 204 determines whether the lighting is front-light or back-light.

[0089] In S1403, the camera control unit 204 determines whether the latest frontlight / backlight determination result is a backlight state (backlight shooting). The frontlight / backlight determination result used in this step is the frontlight / backlight result in the state before the shooting direction was changed. If the camera control unit 204 determines that the determination result is a backlight state, it executes the process of S1404, and if it determines that this is not the case, it executes the process of S1405.

[0090] In S1404, the camera control unit 204 calculates an exposure control value for front light. Changing the shooting orientation rotates the camera unit 20 by 180 degrees, so it is expected that the front light and back light conditions will be switched. Therefore, by changing the exposure control value in accordance with the shooting orientation change operation, it is possible to reduce the degree to which the exposure for the subject is under or overexposed when the shooting orientation change is complete. For example, the exposure control value for front light is set to change the exposure control value for back light conditions by a fixed number of steps to a darker control value. Instead of a fixed number of steps, the exposure control value for front light may be calculated from the luminance distribution in back light conditions.

[0091] In S1405, the camera control unit 204 determines whether the latest front-light / back-light determination result is a front-light state (front-light shooting). If the camera control unit 204 determines that the determination result is a front-light state, it executes the process of S1406, and if it determines that the determination result is not a front-light state, that is, neither a front-light state nor a back-light state, it ends this flow.

[0092] In S1406, the camera control unit 204 calculates an exposure control value for backlight. For example, the exposure control value for backlight is set so as to change the exposure control value for frontlight to a brighter control value by a fixed number of steps. Instead of a fixed number of steps, the exposure control value for backlight may be calculated from the luminance distribution in frontlight.

[0093] In S1407, the camera control unit 204 changes the exposure control value.

[0094] As described above, according to the configuration of this embodiment, in the function for switching the shooting orientation, control is performed to change the exposure control value based on the frontlight / backlight determination result when the shooting orientation switching is initiated. After that, control is performed to detect the subject after the shooting orientation switching is completed and, once AF is enabled, to perform subject tracking and AF drive. This allows the subject to be detected more quickly after the shooting orientation switching when the shooting orientation switching function is executed, enabling the photographer to start shooting more quickly. [Third embodiment] In this embodiment, only the configuration that is different from the first embodiment will be described, and a description of the similar configuration will be omitted. (Configuration of imaging device) FIG. 15 is a configuration diagram of a digital camera, which is an example of an imaging device of this embodiment. In this embodiment, the gimbal unit 30 is configured to be separable from the lens unit 10 and the camera unit 20. The lens unit 10, the camera unit 20, and the gimbal unit 30 are configured to be able to communicate with each other. The gimbal unit 30 does not have a display 302 or a memory 304. The camera unit 20 has a display 208, an operation unit 209, and a memory 210 in addition to the configuration of the first embodiment. The display 208 and the memory 210 have the same functions as the display 302 and the memory 304 in FIG. 1, respectively, and detailed description thereof will be omitted. The operation unit 303 of the gimbal unit 30 is basically used to operate the gimbal unit 30, and the operation unit 209 of the camera unit 20 is basically used to operate the lens unit 10 and the camera unit 20.

[0095] The camera control unit 204 and the gimbal control unit 301 have a function for communicating with each other. The communication method may be wireless communication or wired communication. (Details of various processes performed by the camera unit 20) In this embodiment, the various processes performed by the camera unit 20 are similar to those described in the first embodiment, and therefore detailed description thereof will be omitted.

[0096] The disclosure of this embodiment includes the following configuration. (Configuration 1) an imaging means for outputting an imaging signal corresponding to an optical image formed by the optical system; a driving means for changing the photographing direction of the imaging means; a control unit for controlling the aperture position of the aperture included in the optical system, The imaging device is characterized in that the control means is capable of changing the aperture position to a predetermined position in response to the start of the change in the photographing direction. (Configuration 2) 2. The imaging device according to claim 1, wherein the control means changes the aperture position to the predetermined position in response to the start of the change in the imaging direction when the imaging direction is changed toward the photographer. (Configuration 3) The imaging device according to configuration 2, wherein the control means changes the diaphragm position to the predetermined position in response to the start of the change in the shooting direction when the diaphragm position is positioned on the open side of the predetermined position. (Configuration 4) The imaging device according to configuration 2 or 3, wherein the control means changes the aperture position to the predetermined position in response to start of change of the shooting direction when a difference between the current aperture position and the predetermined position is greater than a predetermined amount. (Configuration 5) The imaging device according to any one of configurations 2 to 4, wherein the control means changes the aperture position to the predetermined position if an exposure control value when the aperture position is changed to the predetermined position satisfies a predetermined condition. (Configuration 6) an imaging means for outputting an imaging signal corresponding to an optical image formed by the optical system; a driving means for changing the photographing direction of the imaging means; a determination means for determining whether or not backlit photography is being performed; a control means for setting an exposure control value; The control means changes the exposure control value to an exposure control value determined based on the result of the determination made by the determination means in response to start of the change in the shooting direction. (Configuration 7) The imaging device according to any one of configurations 1 to 6, wherein the control means drives a focus lens included in the optical system based on the imaging signal in response to completion of the change in the imaging direction. (Configuration 8) The imaging device according to configuration 7, wherein the control means completes driving of the focus lens in response to completion of the change in the shooting direction, and then changes the aperture position to the aperture position before the change in the shooting direction. (Configuration 9) The imaging device according to any one of configurations 1 to 8, wherein the control means controls the drive means to track a subject when the subject is detected based on the imaging signal. (Configuration 10) 10. The imaging device according to any one of configurations 1 to 9, wherein the imaging means is fixed to the driving means. (Configuration 11) the imaging means is detachable from the driving means, 10. The imaging device according to any one of configurations 1 to 9, wherein the imaging means and the driving means are capable of communicating with each other. (Configuration 12) 12. The imaging device according to any one of configurations 1 to 11, wherein the driving means is capable of rotating in at least one of a pan direction and a tilt direction.

[0097] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0098] 30 Gimbal section (drive means) 102 aperture 201 Imaging element (imaging means) 204 Camera control unit (control means)

Claims

1. an imaging means for outputting an imaging signal corresponding to an optical image formed by the optical system; a driving means for changing the photographing direction of the imaging means; a control unit for controlling the aperture position of the aperture included in the optical system, The imaging device is characterized in that the control means is capable of changing the aperture position to a predetermined position in response to the start of the change in the photographing direction.

2. 2. The imaging device according to claim 1, wherein the control means changes the aperture position to the predetermined position in response to the start of the change in the imaging direction when the imaging direction is changed toward the photographer.

3. 3. The imaging device according to claim 2, wherein the control means changes the aperture position to the predetermined position in response to the start of the change in the photographing direction when the aperture position is located more open than the predetermined position.

4. 3. The imaging device according to claim 2, wherein the control means changes the aperture position to the predetermined position in response to the start of the change in the shooting direction when a difference between the current aperture position and the predetermined position is greater than a predetermined amount.

5. 3. The imaging device according to claim 2, wherein the control means changes the aperture position to the predetermined position if an exposure control value when the aperture position is changed to the predetermined position satisfies a predetermined condition.

6. an imaging means for outputting an imaging signal corresponding to an optical image formed by the optical system; a driving means for changing the photographing direction of the imaging means; a determination means for determining whether or not backlit photography is being performed; a control means for setting an exposure control value; The control means changes the exposure control value to an exposure control value determined based on the result of the determination made by the determination means in response to start of the change in the shooting direction.

7. 7. The imaging device according to claim 1, wherein the control means drives a focus lens included in the optical system based on the imaging signal in response to completion of the change in the imaging direction.

8. The imaging device according to claim 7, wherein the control means changes the aperture position to the aperture position before the change in the shooting direction after completing the drive of the focus lens in response to completion of the change in the shooting direction.

9. 7. The imaging apparatus according to claim 1, wherein the control means controls the driving means so as to track a subject when the subject is detected based on the imaging signal.

10. 7. The imaging device according to claim 1, wherein the imaging means is fixed to the driving means.

11. the imaging means is detachable from the driving means, 7. The imaging device according to claim 1, wherein the imaging means and the driving means are capable of communicating with each other.

12. 10. The imaging apparatus according to claim 1, wherein the driving means is capable of rotating in at least one of a pan direction and a tilt direction.

Images