Imaging apparatus, control device, and imaging system

An imaging apparatus capable of communicating with an external control device and configured to capture a subject image formed via an optical member includes a communication interface and a controller, wherein the controller starts the driving of the optical member based on a first command received from the control device via the communication interface, and wherein when the communication interface receives from the control device a second command different from the first command before completion of driving control of the optical member, the controller updates a target position as a target of driving the optical member based on the second command.

TECHNICAL FIELD

The present disclosure relates to an imaging apparatus, a control device capable of communicating with the imaging apparatus, and an imaging system including the imaging apparatus and the control device.

BACKGROUND

A technology for remotely operating an imaging apparatus by using another electronic control device has been known. For example, JP 2015-2471 A discloses a technology for quickly setting specific parameters such as driving amount of a focus lens of an imaging apparatus by a touch operation in an imaging system in which the imaging apparatus and a smartphone are combined.

SUMMARY

Incidentally, when a cut of a specific scene of a movie is captured by a cinema camera, it is necessary to set a desired focus state or zoom state. In JP 2015-2471 A, since the driving amount of the focus lens of the imaging apparatus is set by the touch operation, it is difficult to set a target position of the focus lens for obtaining a desired focus state.

An object of the present disclosure is to provide an imaging apparatus, a control device, and an imaging system that is easy to drive a lens member to a target position with reflecting user intention.

An imaging apparatus according to the present disclosure is an imaging apparatus capable of communicating with an external control device and configured to capture a subject image formed via an optical member, the imaging apparatus comprising: a communication interface configured to receive from the control device a command related to driving of the optical member; and a controller configured to control the driving of the optical member based on the command, wherein the controller starts the driving of the optical member based on a first command received from the control device via the communication interface, and wherein

when the communication interface receives from the control device a second command different from the first command before completion of driving control of the optical member, the controller updates a target position as a target of driving the optical member based on the second command.

A control device according to the present disclosure is a control device capable of communicating with an imaging apparatus configured to capture a subject image formed via an optical member, the control device comprising: an operation member movable according to user operation; a controller configured to generate a command related to driving of the optical member according to a movement operation of the operation member; and a communication interface configured to transmit the command to the imaging apparatus, wherein when the movement operation of the operation member is started, the controller generates a first command for starting the driving of the optical member and then transmits the first command to the imaging apparatus via the communication interface, and wherein during the movement operation being continued, the controller generates a second command for updating a target position as a target of driving the optical member and then transmits the second command to the imaging apparatus via the communication interface.

An imaging system according to the present disclosure includes an imaging apparatus configured to capture a subject image formed via an optical member; and a control device capable of communicating with the imaging apparatus, wherein the imaging apparatus includes a first communication interface configured to receive a command related to driving of the optical member from the control device, and a first controller configured to control the driving of the optical member based on the command, the control device includes an operation member movable according to user operation, a second controller configured to generate the command according to a movement operation of the operation member, and a second communication interface configured to transmit the command to the imaging apparatus, wherein when the movement operation of the operation member is started, the second controller in the control device generates a first command for starting the driving of the optical member and then transmits the first command to the imaging apparatus via the second communication interface, wherein during the movement operation being continued, the second controller generates a second command for updating a target position as a target of driving the optical member and then transmits the second command to the imaging apparatus via the second communication interface, and the first controller in the imaging apparatus starts the driving of the optical member based on the first command received from the control device via the first communication interface, and updates the target position as the target of driving the optical member based on the second command different from the first command when the first communication interface receives the second command from the control device before the driving control of the optical member is completed.

According to the imaging apparatus, the control device, and the imaging system according to the present disclosure, it is easy to drive the lens member to the target position with reflecting user intention.

DETAILED DESCRIPTION

Hereinafter, an embodiment will be described in detail while appropriately referring to the drawings. However, unnecessarily detailed description may be omitted. For example, detailed descriptions of already well-known matters and redundant descriptions for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art.

The applicant provides the accompanying drawings and the following description in order for those skilled in the art to fully understand the present disclosure, and do not intend to limit the subject matter described in the claims by the accompanying drawings and the following description.

Embodiment

Hereinafter, a configuration of a remote imaging system of the present embodiment will be described with reference to the drawings.

1-1. Configuration of Remote Imaging System

FIG. 1is a diagram illustrating a configuration of a remote imaging system of the present embodiment. As illustrated inFIG. 1, an imaging system A of the present embodiment includes a digital camera1and an external device (external communication device or control device)300.

The external device300is an external control device capable of communicating with the digital camera1. The external device300includes a wireless communication interface310and a dial part320. The wireless communication interface310includes a liquid crystal monitor356, an operation member359, and the like.

The external device300is capable of giving instructions (remote operations) to the digital camera1such as a focus operation, a zoom operation, a stop operation, and a release button press for the digital camera1via the communication interface310of the external device300. The digital camera1receives the instructions from the external device300via a communication interface of the digital camera, and then operates according to the received instructions.

That is, the present disclosure provides the imaging system A that enables remote operations (focus operation, zoom operation, release operation, and the like) for the digital camera1from the external device300.

1-2. Configuration of Camera Body

FIG. 2is a block diagram illustrating a configuration of the digital camera1according to the embodiment. The digital camera1of the present embodiment includes a camera body100and an interchangeable lens200. The interchangeable lens200is attachable to the camera body100and detachable from the camera body100.

The camera body100(an example of an imaging apparatus) includes an image sensor110, a liquid crystal monitor120, an operation member130, a camera controller140, a body mount150, a power supply160, and a card slot170.

The camera controller140controls the operations of the entire digital camera1by controlling components such as the image sensor110according to an instruction from the operation member130. The camera controller140transmits a vertical synchronization signal to a timing generator112. In parallel with the transmission of the signal, the camera controller140generates an exposure synchronization signal. The camera controller140periodically transmits the generated exposure synchronization signal to a lens controller240via the body mount150and a lens mount250. The camera controller140uses a DRAM141as a work memory during a control operation and an image processing operation.

The image sensor110is an element configured to capture a subject image incident through the interchangeable lens200to generate image data. The image sensor110is, for example, a CMOS image sensor. The generated image data is digitized by an AD converter111. The camera controller140performs predetermined image processing on the digitized image data. The predetermined image processing is, for example, gamma correction processing, white balance correction processing, flaw correction processing, YC conversion processing, electronic zoom processing, and JPEG compression processing. The image sensor110may be a CCD, an NMOS image sensor, or the like.

The image sensor110operates at a timing controlled by the timing generator112. The image sensor110generates a still image, a moving image, or a live preview image for recording. The live preview image is mainly the moving image, and is displayed on the liquid crystal monitor120for a user to decide a composition for capturing a still image.

The liquid crystal monitor120displays an image such as the live preview image and various kinds of information such as a menu screen. Instead of the liquid crystal monitor, another type of display device, for example, an organic EL display device may be used.

A communication interface142is a wireless or wired communication interface. In the present embodiment, the camera controller140is capable of transmitting to the external device300lens information (performance data) of a focus lens230, driving ability information of a focus lens driver233, information regarding a communication period with an external equipment, and the like, by using Picture Transfer Protocol (PTP) with USB communication via the communication interface142.

The operation member130includes various operation members such as a release button for instructing start of imaging, a mode dial for setting a shooting mode, and a power switch.

A flash memory143functions as an internal memory for recording image data and the like. The flash memory143stores programs regarding autofocus control (AF control) and communication control as well as programs for overall control of operation of the entire digital camera1and information regarding a communication period with external equipment.

A memory card171is attachable to the card slot170and is controlled by the camera controller140. The digital camera1is able to store image data in the memory card171and also read out the image data from the memory card171.

The power supply160is a circuit to supply power to each element in the digital camera1.

The body mount150can be mechanically and electrically connected to the lens mount250of the interchangeable lens200. The body mount150is able to transmit data to the interchangeable lens200via the lens mount250and to receive data from the interchangeable lens200via the lens mount250. The body mount150transmits the exposure synchronization signal received from the camera controller140to the lens controller240via the lens mount250. The body mount150transmits other control signals received from the camera controller140to the lens controller240via the lens mount250. The body mount150transmits the signal received from the lens controller240via the lens mount250to the camera controller140. The body mount150supplies the power from the power supply160to the entire interchangeable lens200via the lens mount250.

1-3. Configuration of Interchangeable Lens

The interchangeable lens200includes an optical system B, the lens controller240, and the lens mount250. The optical system B includes a zoom lens210, the focus lens230, and a stop260. The zoom lens210, the focus lens230, and the stop260are all optical members for forming a subject image captured by the image sensor110of the digital camera1.

The zoom lens210is a lens for changing a magnification of the subject image formed by the optical system B. The zoom lens210is composed of one or a plurality of lenses. The zoom lens210is driven by a zoom lens driver211. The zoom lens driver211includes a zoom ring operable by the user. Alternatively, the zoom lens driver211may include a zoom lever and an actuator or a motor. The zoom lens driver211moves the zoom lens210along an optical axis direction of the optical system B according to user operation.

The focus lens230is a lens for changing a focus state of the subject image formed on the image sensor110by the optical system B. The focus lens230is composed of one or a plurality of lenses. The focus lens230is driven by the focus lens driver233.

The focus lens driver233includes an actuator or a motor to move the focus lens230along an optical axis of the optical system B based on control by the lens controller240. The focus lens driver233may be achieved by a DC motor, a stepping motor, a servo motor, an ultrasonic motor, or the like.

The stop260adjusts an amount of light incident on the image sensor110. The stop260is driven by a stop driver262to control a size of an opening of the stop260. The stop driver262includes a motor or an actuator.

The camera controller140and the lens controller240may be achieved by a hardwired electronic circuit, a microcomputer using a program, or the like. For example, the camera controller140and the lens controller240may be achieved by a processor such as a CPU, an MPU, a GPU, a DSP, an FPGA, or an ASIC.

1-4. Configuration of External Device

FIG. 3is a block diagram illustrating a configuration of the external device300. The configuration of the external device300will be described with reference toFIG. 3below.

The external device300includes the wireless communication interface310and the dial part320. The wireless communication interface310includes a controller351, a DRAM (work memory)352, a flash memory353, a communication interface354, the liquid crystal monitor356, the operation member359, and a power supply360. The dial part320is an operation member including a rotation operation member357and a rotation detector358.

The controller351is a processing unit configured to control processing in the external device300as a whole. The controller351is electrically connected to the DRAM352, the flash memory353, the communication interface354, the liquid crystal monitor356, the rotation detector358, and the operation member359. The controller351accepts operation information indicating an operation of the user via the operation member359. The operation member359includes various operation members such as buttons for selecting the focus operation, the zoom operation, or the stop operation for the remote operation, a release button for instructing start of imaging, and the power switch. The controller351is capable of reading out data stored in the flash memory353. The controller351also controls power supplied to each unit of the external device300from the power supply360.

The DRAM352is a memory configured to temporarily store information necessary for the controller351to execute various processing operations.

The flash memory353is a large-capacity non-volatile memory for storing various kinds of data. As described above, various kinds of data stored in the flash memory353can be read out by the controller351.

The controller351acquires lens data (information of the focus lens230and driving ability information of the driver233for driving the focus lens230) stored in the flash memory242of the digital camera1via the communication interface354, and then stores the lens data in the flash memory353.

The liquid crystal monitor356is a display configured to display a screen instructed by the controller351. The controller351displays a rotation operation amount (positional information and movement amount) on the liquid crystal monitor356as operation information regarding rotation operation of the rotation operation member357. Accordingly, the user can visually see the operation amount of the rotation operation.

The communication interface354is a wireless or wired communication interface. In the present embodiment, the controller351is capable of transmitting a command (instruction signal) for controlling the digital camera1to the communication interface142of the camera body100by USB communication via the communication interface354by using Picture Transfer Protocol (PTP).

The rotation operation member357is an input device to accept the rotation operation of the user. The rotation operation member357transmits the operation information corresponding to an accepted rotation operation of the user to the rotation detector358. The rotation detector358obtains an output voltage corresponding to the rotation operation amount, and then transmits this output signal to the controller351.

The controller351acquires the output signal from the rotation detector358at a fixed period (for example, 4 msec) to calculate rotation angle information (rotation angle θ [rad]) and rotation angular velocity information (ω=θ/4 [rad/msec]). Reflecting this calculation result by using the rotation angle information and the rotation angular velocity information stored in the flash memory353periodically (for example, every 100 msec) according to the rotation operation of the rotation operation member357, the controller351generates a command (drive instruction information). The controller351communicates with the camera controller140of the digital camera1by transmitting the command to the communication interface142of the digital camera1via the communication interface354.

2-1. Outline of Remote Operation

First, an outline of the remote operation will be described.

FIG. 4is a sequence diagram illustrating from generation of a driving instruction command to completion of lens driving, where a target position is not updated. Not-updating of the target position means that the controller351of the external device300does not issue a driving instruction command until operation of the rotation operation member357is completed. For the sake of convenience, rotation operation amounts for setting predetermined focus distances (10 m, 5 m, 3 m, 2 m, and 1.5 m) of the digital camera1are represented on the rotation operation member357. A focus distance of “10 m” means that a distance from the digital camera1to the subject to be focused is 10 m. For example, the user performs the rotation operation of the rotation operation member357up to a position indicating 10 m (focus adjustment position (1)) in order to set the focus distance of the digital camera1to 10 m. InFIG. 4, a rotation position of the rotation operation member357is represented by (0) to (4), and the rotation positions (1) to (4) correspond to the focus adjustment positions (1) to (4), respectively. The same applies to the following diagrams.

In the case ofFIG. 4, when the rotation position reaches the position corresponding to the focus distance 2 m (focus adjustment position (4)) at which the operation of the rotation operation member357is completed, the controller351issues a driving instruction command 1 for driving the focus lens230such that the focus distance becomes 2 m from an infinite end (Inf) for the first time. When the driving instruction command 1 is accepted, the controller140of the camera returns an instruction reception OK and issues a driving instruction command 2 to the lens controller240. The lens controller240accepts the driving instruction command 2 and then drives the focus lens230such that the focus distance is 2 m from the infinite end (Inf). After driving of the focus lens230is completed, the lens controller240transmits a driving completion notification to the camera controller140, and then the camera controller140receives the driving completion notification and sends it to the controller351of the external device.

As described above, when the target position is not updated inFIG. 4, since the controller351of the external device300does not issue a command until the operation of the rotation operation member357is completed, thereby generating a time lag. In the present embodiment, a driving method to update the target position in order to eliminate this time lag is used.

FIG. 5is a sequence diagram illustrating from generation of a driving instruction command to completion of lens driving, where a target position is updated. Updating of the target position means that the controller351of the external device300issues a command to update a drive position at a predetermined period before the operation of the rotation operation member357is completed. For explanation, any adjacent rotation operation amounts of the rotation operation member357between Inf (focus adjustment position (0)), focus distance 10 m (focus adjustment position (1)), 5 m (focus adjustment position (2)), 3 m (focus adjustment position (3)), 2 m (focus adjustment position (4)), and 1.5 m are set to the same.

FIG. 5illustrates a case where the user performs the rotation operation of the rotation operation member357at a constant speed, and also the controller351issues commands 1 to 4 (driving instruction command 1 and target position updating commands 2 to 4) at the focus adjustment positions (1) to (4), respectively.

When the operation of the rotation operation member357reaches the position corresponding to the focus distance 10 m (focus adjustment position (1), first position), the controller351issues the driving instruction command 1 for driving the focus lens230such that the focus distance becomes 10 m from the infinite end (Inf). The driving instruction command 1 includes information on the focus adjustment position (1) as the target position. When the driving instruction command 1 is accepted, the camera controller140of the digital camera1returns an instruction reception OK and also issues driving instruction command 5 to the lens controller240. The lens controller240accepts the driving instruction command 5 and drives the focus lens230such that the focus distance becomes 10 m from the infinite end (Inf). Subsequently, when the operation of the rotation operation member357reaches the position corresponding to the focus distance 5 m (focus adjustment position (2), second position), the controller351issues target position updating command 2 which is a correction command for driving the focus lens230such that the focus distance becomes 5 m. The target position updating command 2 includes information on the focus adjustment position (2) as the target position. When the target position updating command 2 is accepted, the camera controller140of the digital camera1returns an instruction reception OK and issues target position updating command 6 to the lens controller240. The lens controller240accepts the target position updating command 6 and updates a target so as to drive the focus lens230to the focus distance 5 m. Subsequently to this operation, the driving of the focus lens230is completed to the position corresponding to focus distance of 2 m (focus adjustment position (4)), and then the lens controller240transmits a driving completion notification to the camera controller140. The camera controller140receives the driving completion notification, and sends the driving completion notification to the controller351of the external device300.

As described above, the driving method illustrated inFIG. 5is more effective in eliminating the time lag than the driving method illustrated inFIG. 4. In the example illustrated inFIG. 5, each of commands 1 to 8 includes information on the target position, but does not include information on a start position. The same applies to the following examples.

2-2. Acquisition of Lens Data by Camera Body and Connection Between Digital Camera and External Device

FIG. 6is a sequence diagram related to an acquisition operation of the lens data (lens information and performance data) by the camera body100and a connection operation between the camera body100and the external device300. In the present embodiment, the connection operation between the camera body100and the external device300is achieved by USB communication using Picture Transfer Protocol (PTP).

Below, an acquisition operation of the lens data by the camera body100will be described with reference toFIG. 6.

When the power supply is turned on, the camera controller140of the camera body100supplies power to each component of the camera body100, and enables the camera body100to perform imaging and communication. Thereafter, the camera controller140starts the power supply from the power supply160to the interchangeable lens200from the camera body100via the body mount150and the lens mount250(E600). Subsequently, the camera controller140and the lens controller240performs a lens authentication request (E601), a lens authentication response (E602), a lens initialization request (E603), and a lens initialization completion response (E604) with each other, and then the camera controller140issues a lens data request to the lens controller240(E605). The camera controller140accepts a lens data response sent from the lens controller240(E606), and then acquires the lens data that has been stored in the flash memory242of the interchangeable lens200. The camera controller140stores the acquired lens data in the flash memory143of the camera body100. The lens data is performance data indicating performance related to the driving of the focus lens230. Details of the lens data will be described later.

Next, a connection operation (that is, initial communication) between the camera body100and the external device300will be described with reference toFIG. 6. An operation related to the external device300will be described below. When the power supply is turned on, the controller351of the external device300supplies the power of the power supply360to each component of the external device300, and enables the external device300to perform communication. The user selects a menu for issuing a communication start instruction by operating the operation member359of the external device300. When the user selects the menu for issuing the communication start instruction (S600), the external device300becomes a standby state waiting for connection from the camera body100(S601).

Next, an operation related to the digital camera1will be described. After the power supply is turned on, the user operates the operation member130of the camera body100to display the menu screen on the liquid crystal monitor120. The user selects a menu for issuing a communication start instruction by operating a touch panel on the liquid crystal monitor120. When the user selects the menu for issuing the communication start instruction (S602), the camera body100becomes a state of starting the connection to the external device300(S603).

The controller351of the external device300notifies the camera controller140of the digital camera1of a connection request via the communication interface354(E600). When the connection request is accepted, the camera controller140of the digital camera1notifies the external device300of a connection permission via the communication interface142(E601). Accordingly, communication between the digital camera1and the external device300is established.

2-3. Data Request Communication from External Device

FIG. 7is a sequence diagram related to a request operation of the lens data from the external device300to the digital camera1.

After the communication between the digital camera1and the external device300is established through the above initial communication, a request operation of the lens data (or camera information) from the external device300to the digital camera1is performed, which will be described with reference toFIG. 7below.

The controller351of the external device300issues a lens data request to the camera body100in response to button press of the operation member359as an operation for acquiring the lens data in the digital camera1(E700). The lens data request is a request for acquiring focus table data and information regarding a communication period of the digital camera1(camera body100) to communicate with external equipment. Although the lens data request is issued to the camera body100according to the button press of the operation member359by the user after the communication is established between the digital camera1and the external device300, the present embodiment is not limited thereto. For example, the controller351of the external device300may automatically acquire the focus table data, the information regarding the communication period of the camera body100, and the like immediately after the communication is established between the external device300and the digital camera1. When the camera controller140receives the lens data request, the controller351of the external device300accepts a lens data response sent from the camera controller140(E701), and then acquires the focus table data and the information regarding the communication period which has been stored in the flash memory143of the camera body100. Although the controller351of the external device300acquires the focus table data and the information regarding the communication period of the camera body100by issuing the lens data request, a request for the focus table data and a request for the information regarding the communication period of the camera body100may be separately issued.

Subsequently, the controller351of the external device300issues a lens data request to the camera body100for acquiring information regarding a maximum speed and a minimum speed for driving the focus motor (E702). When the camera controller140receives the lens data request, the controller351of the external device300accepts a lens data response sent from the camera controller140(E703), and then acquires the information on the maximum speed and the minimum speed of the focus motor (focus lens driver233), which has been stored in the flash memory143of the camera body100. The controller351stores in the flash memory353the acquired focus table data and the acquired maximum speed information and minimum speed information for driving the focus motor (driving ability information of the focus lens driver233; focus speed information).

As stated above, the external device300is able to acquire the focus table data and the focus speed information stored in the flash memory242of the interchangeable lens200of the digital camera1before the remote operation. Here, examples of the focus table data and the focus speed information as the lens data are illustrated inFIGS. 8A and 8B, respectively.

FIG. 8Aillustrates the focus table data. InFIG. 8A, numbers of steps of the focus motor are illustrated until reaching focus distances (infinite end (Inf), 10 m, 5 m, 3 m, 2 m . . . 0.9 m) to the subject to be focused with the focus lens230for any of focal lengths 14 mm, 25 mm, and 50 mm.FIG. 8Billustrates the focus speed information.FIG. 8Billustrates the maximum speed information and the minimum speed information for driving the focus motor.

2-4. Remote Focus Operation of Digital Camera by External Device (when Focus Speed is not Designated)

A remote focus operation of the digital camera1by the external device300will be described with reference toFIGS. 9A, 9B, and 9C.

FIG. 9Ais a diagram for describing a rotation operation of the rotation operation member357, andFIG. 9Bis a graph representing a driving state of the focus lens230over time.FIG. 9Cis a graph including the graph ofFIG. 9Band the graph ofFIG. 5added thereto.

In this example, designation of the focus speed is not included in a command for the remote focus operation from the external device300.

FIG. 9Ashows the rotation operation member357in a similar way toFIGS. 4 and 5. In this example, the user performs the rotation operation for the rotation operation member357at a constant speed as inFIG. 5, and commands 1 to 4 (driving instruction command 1 and target position updating commands 2 to 4) are issued at focus distance 10 m (focus adjustment position (1)), 5 m (focus adjustment position (2)), 3 m (focus adjustment position (3)), and 2 m (focus adjustment position (4)). In this example, the communication period from the external device300to the digital camera1is 100 msec and the rotation operation member357of the external device300is operated at the speed illustrated inFIG. 9A. That is, as illustrated inFIG. 9B, commands 1 to 4 for driving the focus lens such that the focus distance becomes positions of 10 m, 5 m, 3 m, and 2 m are issued at every 100 msec. The communication period from the external device300to the digital camera1can be set by using the information regarding the communication period of the camera body100with the external equipment, which has been stored in the flash memory353of the external device300illustrated inFIG. 3.

As described above, the target position updating commands 2 to 4 can be transmitted at every 100 msec which is the communication period of the camera body100, and thus, the focus lens230can be driven while updating the target position of the focus lens230during the operation of the rotation operation member357, that is, during the driving control of the focus lens230.

In the examples illustrated inFIGS. 9A to 9C, when the remote focus operation of the digital camera1is performed by the external device300, the digital camera1drives the focus lens230so as to reach a designated position in a shortest time without including in commands 1 to 4 the focus speed designation for driving the focus lens. Thus, as illustrated inFIGS. 9B and 9C, stop sections of the focus lens230occurs, thereby achieving an intermittent remote focus operation in which “drive” and “stop” are repeated.

Below, a remote focus operation from the external device300including designation of the focus speed will be described. This method can achieve a smoother focus operation, and for example, a cut video in a desired focus state can be captured when the user captures a specific scene of a movie. Thus, smooth capturing without interruption can be achieved, for example, when capturing after a scene illustrated inFIG. 10A(a state of being focused on a tree91in the background) is captured, a scene illustrated inFIG. 10B(a state of being focused on an animal92in front) obtained by near-shifting the focus lens230in a direction for shortened focus distance.

With reference toFIGS. 11A to 13, a case where the focus speed is designated in the remote focus operation from the external device300will be described.

2-5. Remote Focus Operation of Digital Camera by External Device (when Focal Speed is Designated)

FIG. 11Ais a diagram for describing the rotation operation of the rotation operation member357.FIG. 11Bis a graph representing a driving state of the focus lens230over time.FIG. 11Cis a graph including the graph ofFIG. 11Band the graph ofFIG. 5added thereto.

In a first example illustrated inFIGS. 11A to 11C, the communication period from the external device300to the digital camera1is 100 msec and the rotation operation member357of the external device300is operated at the speed illustrated inFIG. 11A(each section of the focus adjustment positions (0) to (4) is operated in 100 msec). Further, a speed range of driving the lens is maximum speed: 30 step/msec and minimum speed: 3 step/msec.

In this example, since the focus speed is designated, commands 1 to 4 (driving instruction command 1 and target position updating commands 2 to 4) including the focus speed are issued at every 100 msec from the controller351of the external device300as illustrated inFIG. 11B. First command 1 includes a position designation (first position): 1000 step and a speed designation (first speed): 10 step/msec toward the focus distance of 10 m. Second command 2 includes a position designation (second position): 2000 step and a speed designation (second speed): 10 step/msec toward the focus distance of 5 m. Third command 3 includes a position designation (third position): 3000 step and a speed designation (third speed): 10 step/msec toward the focus distance of 3 m. The position designations and the speed designations can be included by utilizing the lens data stored in the flash memory353of the external device300illustrated inFIG. 8.

As described above, when the remote focus operation of the digital camera1is performed by the external device300, commands 1 to 4 include the position designation and the speed designation for driving the focus lens, and thus continuous driving can be performed without stopping the focus lens230. Thus, a smooth focus operation can be achieved.

Next, a second example of the remote focus operation of the digital camera1by the external device300when the focus speed is designated will be described with reference toFIGS. 12A to 12C.

FIG. 12Ais a diagram for describing the rotation operation of the rotation operation member357.FIG. 12Bis a graph representing a driving state of the focus lens230over time.FIG. 12Cis a graph illustrating the graph ofFIG. 12Band the graph ofFIG. 5added thereto.

In the second example, the communication period from the external device300to the digital camera1is 100 msec and the rotation operation member357of the external device300is operated at the speed illustrated inFIG. 12A(each section of the focus adjustment positions (0) to (5) is operated in 100 msec or 50 msec). The speed range for driving the lens is maximum speed: 30 step/msec and minimum speed: 3 step/msec. In this example, unlike the first example, the rotation operation member357is operated faster from the middle.

In this example, the focus speeds are designated, and commands 1 to 3 including the focus speeds can be issued from the controller351of the external device300at every 100 msec as illustrated inFIG. 12B.

This example of the remote focus operation of the digital camera1by the external device300will be described with reference toFIGS. 12A to 12C.

In this example, the interchangeable lens200including the focus lens230having a focal length of 14 mm is attached to the camera body100. Also, the lens data illustrated inFIGS. 8A and 8Bis stored in the flash memory353of the external device300in advance by the communication between the external device300and the camera body100as illustrated inFIG. 7.

The controller351of the external device300calculates the rotation angle information and the rotation angular velocity information at every 100 msec by acquiring the output signal from the rotation detector358at a fixed period (for example, 4 msec). Using these calculation results and the lens data ofFIGS. 8A and 8B, the controller351further obtains the number of drives (number of steps) and a driving speed (step/msec) of the focus lens driver233.

Based on the rotation operation of the rotation operation member357of the user illustrated inFIG. 12A, the controller351calculates the number of drives and the driving speed of the focus lens driver233as follows.

(1) By the initial period 100 msec, the rotation operation member357moves from the focus adjustment position (0) to the focus adjustment position (1), and then the controller351calculates the number of drives to 1000 step as the position designation and the driving speed as (1000-0) step/100 msec=10 step/msec as the speed designation toward the focus distance of 10 m while referring toFIG. 8A. Thereafter, the controller351generates the first command 1 including the position designation: 1000 step and the speed designation: 10 step/msec toward the focus distance of 10 m.

(2) After the next period 100 msec, the rotation operation member357moves to the focus adjustment position (3), and then the controller351calculates the number of drives to 3000 step as the position designation and the driving speed to (3000-1000) step/100 msec=20 step/msec as the speed designation toward the focus distance of 3 m while referring toFIG. 8A. Thereafter, the controller351generates second command 2 including the position designation: 3000 step and the speed designation: 20 step/msec toward the focus distance of 3 m.

(3) After the last period 100 msec, the rotation operation member357moves to the focus adjustment position (5), the controller351sets the number of drives to 5000 step as the position designation and the driving speed to (5000-3000) step/100 msec=20 step/msec as the speed designation toward the focus distance of 1.5 m while referring to FIG.8A. Thereafter, the controller351generates third command 3 including the position designation: 5000 steps and the speed designation: 20 steps/msec toward the focus distance of 1.5 m.

In the above-described example, generated commands 1 to 3 includes the driving speeds of 10 step/msec and 20 step/msec, which fall within the maximum speed (30 step/msec) and the minimum speed (3 step/msec) for driving the focus motor illustrated inFIG. 8B. Thus, the focus lens230can be driven normally.

When the driving speed is calculated to exceed the maximum speed for driving the focus motor, the controller351decides the driving speed to be equal to or less than the maximum speed for driving the focus motor. Similarly, when the driving speed is calculated to be lower than the minimum speed for driving the focus motor, the controller351decides the driving speed to be equal to or higher than the minimum speed for driving the focus motor. That is, the driving speed to be included in the commands is decided to be limited in the range from the minimum speed to the maximum speed of the focus lens driver233. As described above, the controller351generates the command including the speed designation reflected by the drive ability information of the focus lens driver233.

FIG. 13is a sequence diagram for achieving the remote focus operation of the digital camera1by the external device300as a second example.

When communicating with the camera body100, the controller351of the external device300performs predetermined PTP protocol processing (E100), and then transmits generated command 1 to the camera controller140via the communication interface354and the communication interface142of the camera body100(E101). The camera controller140accepts command 1 and returns information (OK information) indicating permission for the acceptance of the subsequent command to the controller351of the external device300via the communication interface142and the communication interface354(E102). As stated above, the camera controller140of the camera body100returns the above-described command acceptance permission (OK information) without waiting for the completion of the driving of the focus lens for command 1.

The camera controller140transmits command 4 corresponding to command 1 to the lens controller240of the lens unit200. Thereafter, the lens controller240accepts command 4 and then issues an instruction to the focus lens driver233in response to command 4. The instruction causes the focus lens driver233to drive the focus lens230at a speed of 10 steps/msec toward the focus distance of 10 m. Subsequently, operations of communications (E104) to (E111) are similarly performed.

As described above, in the remote focus operation of the digital camera1by the external device300, the position designation and the speed designation for driving the focus lens are included in commands 1 to 3 for drive instruction, thereby achieving continuous driving without stopping the focus lens230. Driving speed of the focus lens can be changed according to the rotation speed of the rotation operation member357of the external device300. Using the remote focus operation of the present embodiment makes it possible to easily create a cut of scene as intended by the user.

As described above, the digital camera1(imaging apparatus) in the present embodiment is an imaging apparatus capable of communicating with the external device300(external control device) and configured to capture the subject image formed through the focus lens230(optical member). The digital camera1includes the communication interface142configured to receive from the external device300the command related to driving of the focus lens230, and the camera controller140(controller) configured to control the driving of the focus lens230based on the command. The camera controller140starts the driving of the focus lens230based on driving instruction command 1 (first command) received from the external device300by the communication interface142. When the communication interface142receives from the external device300target position updating commands 2 to 4 (second commands) different from the driving instruction command 1 before completion of driving control of the focus lens230, the camera controller140updates the target position as a target of driving the focus lens230based on target position updating commands 2 to 4.

According to the above-described digital camera1, the target position is updated based on target position updating commands 2 to 4 before the completion of driving control of the focus lens230, and thus the driving control of the focus lens230can be executed with updating the target position. Accordingly, it is easy to drive the focus lens230to the target position reflected by the intention of the user.

In the digital camera1of the present embodiment, when the driving control of the focus lens230is completed, the camera controller140transmits the driving completion notification to the external device300via the communication interface142. When the communication interface142receives target position updating commands 2 to 4 before the driving completion notification is transmitted, the camera controller140updates the target position based on target position updating commands 2 to 4. Accordingly, the target position of the focus lens230can be updated before the driving completion notification is transmitted.

In the digital camera1of the present embodiment, driving instruction command 1 includes the first position as the target position, and target position updating command 2 includes the second position different from the first position as the target position. The camera controller140starts the driving of the focus lens230toward the first position based on driving instruction command 1. The camera controller140further updates the target position from the first position to the second position during the driving control of the focus lens230based on target position updating command 2. Accordingly, the focus lens230can be driven toward different positions based on driving instruction command 1 and the target position updating command 2.

In the digital camera1of the present embodiment, the camera controller140controls the driving speed of the focus lens230at the first speed based on driving instruction command 1 until the focus lens230reaches the first position. The camera controller140further controls the driving speed of the focus lens230at the second speed based on target position updating command 2 until the focus lens230reaches the second position after reaching the first position. Accordingly, the driving speed of the focus lens230can be controlled based on each of driving instruction command 1 and target position updating command 2.

In the digital camera1of the present embodiment, the communication interface142receives target position updating commands 2 to 4 from the external device300at each predetermined communication period after receiving driving instruction command 1. Based on each received target position updating commands 2 to 4, the camera controller140subsequently controls the driving of the focus lens230. Accordingly, target position updating commands 2 to 4 are received at desired periods, each of which affects the driving control of the focus lens230.

The digital camera1of the present embodiment further includes the flash memory143(storage) configured to store the lens data (performance data) indicating the performance related to the driving of the focus lens230. The camera controller140transmits the lens data to the external device300via the communication interface142, and driving instruction command 1 and target position updating commands 2 to 4 are set according to the lens data. Accordingly, the external device300can reflect the lens data in setting the commands.

The digital camera1of the present embodiment is further configured to be attachable with the interchangeable lens200thereto, and the focus lens230is an optical member provided on the interchangeable lens200. Accordingly, the driving control using target position updating commands 2 to 4 can be applied to the focus lens230of the interchangeable lens200.

The external device300(control device) in the present embodiment is a control device capable of communicating with the digital camera1(imaging apparatus) configured to capture the subject image formed via the focus lens230(optical member). The external device300includes the dial part320(operation member) movable according to user operation, the controller351configured to generate the command related to the driving of the focus lens230according to the movement operation of the dial part320, and the communication interface354configured to transmit the command to the digital camera1. When the movement operation of the dial part320is started, the controller351generates driving instruction command 1 for starting the driving of the focus lens230and then transmits the driving instruction command to the digital camera1via the communication interface354. During the movement operation of the dial part320being continued, the controller351further generates target position updating commands 2 to 4 for updating the target position as the target of driving the focus lens230, and then transmits the target position updating commands to the digital camera1via the communication interface354.

According to the above-described external device300, target position updating commands 2 to 4 are transmitted to the digital camera1while the movement operation of the dial part320is being continued. Thus, the driving control of the focus lens230can be performed while updating the target position. Accordingly, it is easy to drive the focus lens230to the target position reflected with user intention.

In the external device300of the present embodiment, after driving instruction command 1 is transmitted, the communication interface354transmits target position updating commands 2 to 4 to the digital camera1before the driving completion notification is received from the digital camera1. Accordingly, the target position of the focus lens230can be updated without waiting for receiving the driving completion notification.

In the external device300of the present embodiment, the controller351causes driving instruction command 1 to include the first position as the target position based on the operation amount of the dial part320when the movement operation is started. The controller351further causes target position updating command 2 to include the second position different from the first position as the target position based on the operation amount of the dial part320when the movement operation is being continued. Accordingly, the focus lens230can be driven toward different positions based on driving instruction command 1 and target position updating command 2.

The external device300of the present embodiment further includes the flash memory353configured to store the lens data indicating the performance related to the driving of the focus lens230. The controller351causes driving instruction command 1 to include the first speed for driving the focus lens230to the first position based on the lens data and the operation amount of the dial part320when the movement operation is started. The controller351further causes target position updating command 2 to include the second speed for driving the focus lens230to the second position based on the lens data and the operation amount of the dial part320when the movement operation is being continued. Accordingly, the driving speed of the focus lens230can be controlled based on each of driving instruction command 1 and target position updating command 2.

In the external device300of the present embodiment, the controller351acquires the lens data (performance data) from the digital camera1via the communication interface354, and then records the lens data in the flash memory353. Accordingly, the controller351can reflect the lens data in setting the commands 1 to 4.

In the external device300of the present embodiment, the controller351generates target position updating commands 2 to 4 at each predetermined communication period based on the movement operation being continued after driving instruction command 1 is generated, and subsequently transmits the target position updating commands to the digital camera1via the communication interface354. Accordingly, target position updating commands 2 to 4 are transmitted to the digital camera1at a predetermined communication period, each of which affects the driving control of the focus lens230.

In the external device300of the present embodiment, the dial part320is rotatable for the movement operation. Accordingly, the user can easily operate the dial part.

The imaging system A in the present embodiment is an imaging system including the digital camera1(imaging apparatus) configured to capture the subject image formed via the focus lens230(optical member) and the external device300(control device) capable of communicating with the digital camera1. The digital camera1includes the communication interface142configured to receive the command related to the driving of the focus lens230from the external device300, and the camera controller140configured to control the driving of the focus lens230based on the command. The external device300includes the dial part320movable according to user operation, the controller351configured to generate the command according to the movement operation of the dial part320, and the communication interface354configured to transmit the command to the digital camera1. In the external device300, when the movement operation of the dial part320is started, the controller351generates driving instruction command 1 for starting the driving of the focus lens230and then transmits the driving instruction command to the digital camera1via the communication interface354. The controller351further generates the target position updating commands 2 to 4 for updating the target position as the target of the driving of the focus lens230during the movement operation being continued, and then transmits the target position updating commands to the digital camera1via the communication interface354. In the digital camera1, the camera controller140starts the driving of the focus lens230based on driving instruction command 1 received from the external device300via the communication interface142. The camera controller140further updates the target position as the target of driving the focus lens230based on target position updating commands 2 to 4 when the communication interface142receives target position updating commands 2 to 4 from the external device300before the driving control of the focus lens230is completed.

According to the above-described imaging system A, the target position is updated based on target position update commands 2 to 4 before the completion of the driving control of the focus lens230. Accordingly, it is easy to drive the focus lens230toward the target position reflected with user intention.

By the imaging system A of the present embodiment, the camera controller140in the digital camera1transmits the driving completion notification to the external device300via the communication interface142when the driving control of the focus lens230is completed, the communication interface354in the external device300transmits target position updating commands 2 to 4 to the digital camera1before the driving completion notification is received from the digital camera1after driving instruction command 1 is transmitted and, and the camera controller140in the digital camera1updates the target position based on target position updating commands 2 to 4 when the communication interface142receives target position updating commands 2 to 4 before the driving completion notification is transmitted. Accordingly, the target position of the focus lens230can be updated before the driving completion notification is transmitted.

Other Embodiments

The present disclosure is not limited to the above-described embodiment, and various embodiments can be considered.

Hereinafter, other embodiments of the present disclosure will be described.

In the above-described embodiment, the remote control is used for the focus operation. However, the remote control can be similarly used for the zoom operation or the stop operation. That is, the present disclosure is not limited to the driving control of the focus lens230as the optical member, and applicable to driving control of the zoom lens210or the stop260. For example, once the zoom operation or the stop operation is selected with a dedicated button of the operation member359of the external device300, the selected remote control can be achieved.

FIGS. 14A and 14Bshow lens data used when the stop operation is selected as the remote control.FIG. 14Aillustrates stop table data, including the number of steps of a stop motor until reaching F-numbers (F2.8, F3.0, F3.2, F3.5, F3.8, F4.0 . . . F22) of the stop260for any of the focal lengths of 14 mm, 25 mm, and 50 mm.FIG. 14Billustrates stop speed information, including maximum speed information and minimum speed information of the stop driver262.

For generating the driving instruction command or the target position updating command related to driving of the stop260, the stop table data illustrated inFIG. 14Ais referred to calculate the position designation, and the stop speed information illustrated inFIG. 14Bis referred to calculate the speed designation.

FIGS. 15A and 15Bshow lens data used when the zoom operation is selected as the remote control.FIG. 15Aillustrates zoom table data, including the number of steps of a zoom motor until reaching the focal lengths (14 mm, 14.1 mm, 14.2 mm, 14.3 mm, 14.4 mm, 14.5 mm . . . 50 mm).FIG. 15Billustrates zoom speed information, including maximum speed information and minimum speed information of the zoom lens driver211.

For generating the driving instruction command or the target position updating command related to driving of the zoom lens210, the zoom table data illustrated inFIG. 15Ais referred to calculate the position designation, and the zoom speed information illustrated inFIG. 15Bis referred to calculate the speed designation.

Also, the digital camera1is not limited to the interchangeable lens type camera like the above-described embodiment, and a lens-integrated camera may also be applied.

Although the dial part320is used as the operation member of the external device300in the above-described embodiment, not limited to the rotatable operation member (dial part), a linear-slidable operation member may be applied.

Although the communication operation between the digital camera1and the external device300is achieved by the USB communication in the above-described embodiment, the camera controller140may communicate with the external device300by using Picture Transfer Protocol (PTP) by Bluetooth (registered trademark), a wireless LAN, a wired LAN, or the like via the communication interface142.

Although instruction content from the controller351is displayed on the liquid crystal monitor356in the above-described embodiment, a driving result of the digital camera1based on the instruction content from the controller351, that is, output value information from the digital camera1may be displayed.

Therefore, not only components which are essential for solving the problems but also components which are not essential for solving the problems in order to illustrate the aforementioned technology may be included in the components described in the accompanying drawings and detailed description. Thus, the fact that the non-essential components are described in the accompanying drawings and detailed description should not directly prove that the non-essential components are essential.

In addition, since the aforementioned preferred embodiments are provided in order to illustrate the technology of the present disclosure, various changes, replacements, additions, and omissions can be performed within the scope of the claims or the equivalents thereof.

The present disclosure can be applied to, for example, a digital camera1configured to capture an image, an external device300(communication equipment) capable of communicating with the digital camera1and configured to perform a remote operation for the digital camera1, and an imaging system including the digital camera1and the external device300. Specifically, the present disclosure is applicable to, for example, a cinema camera, a digital camera, and a movie camera capable of capturing a moving image as the digital camera1.