JP6788368B2 - Accessory device, imaging device and their control method - Google Patents

Description

The present invention relates to an imaging device (hereinafter referred to as a camera body) capable of communicating with each other and an accessory device such as an interchangeable lens.

In an accessory-replaceable camera system that includes a camera body to which an accessory device can be attached and detached, communication is performed so that the camera body controls the accessory device and the accessory device provides the camera body with data necessary for the control and imaging. It is said. In particular, when an interchangeable lens is used to image a video for recording or a video for live view display, smooth lens control is required according to the imaging cycle, so the imaging timing of the camera body and the control timing of the interchangeable lens Need to be synchronized. Therefore, the camera body needs to complete the reception of data from the interchangeable lens and the transmission of various commands and requests to the interchangeable lens within the imaging cycle. However, as the amount of data received by the camera body from the interchangeable lens increases and the imaging cycle is shortened (higher frame rate), communication of a large amount of data is required in a shorter time.

In addition, the camera system is equipped with an image shake correction lens based on the angular velocity detected by the gyro sensor of the interchangeable lens and the amount of movement of the subject image on the image sensor of the camera body when taking a panning shot of a moving subject. There is one that moves and assists panning. In order to realize good panning assist, it is necessary to accurately synchronize the timing when the camera body calculates the amount of movement of the subject image and the timing when the interchangeable lens acquires the angular velocity.

Patent Document 1 notifies the interchangeable lens of the timing of the vertical synchronization signal by maintaining the signal level of the communication terminal at a predetermined level for a predetermined time or longer and then changing the signal level of the communication terminal according to the vertical synchronization signal. The camera system to be used is disclosed.

Japanese Patent No. 5247859

However, in the camera system disclosed in Patent Document 1, it is difficult to secure a predetermined time for maintaining the signal level of the communication terminal at a predetermined level when it is necessary to communicate a large amount of data in a short time. In addition, other communication such as a focus drive command may occur in the interchangeable lens immediately before the generation of the vertical synchronization signal, and the signal level may not be controlled in a timely manner.

The present invention provides an accessory device, an imaging device, and the like that enable processing such as calculation and control by using information in which the timing between the accessory device and the imaging device is accurately synchronized in an interchangeable lens camera system. To do.

The accessory device as one aspect of the present invention is detachably attached to the imaging device. The accessory device is connected to the image pickup device from a notification channel used for notification from the image pickup device to the accessory device, a first data communication channel used for data transmission from the accessory device to the image pickup device, and an image pickup device. Data communication is performed between the accessory communication unit provided with three channels including the second data communication channel used for data transmission to the accessory device and the image pickup device via the accessory communication unit, and changes with time. It has an accessory control unit that acquires accessory information and a timer that counts the time. The accessory control unit acquires the first time at which the transmission request is received from the timer in response to the transmission request as the notification from the image pickup device via the notification channel, and the second data communication from the image pickup device. Acquires accessory information at the first time or at the second time acquired based on the first time in response to receiving a specific command via the channel, and sets the first data communication channel. It is characterized in that accessory information is transmitted to the image pickup apparatus via the image pickup device.

In the imaging device as another aspect of the present invention, an accessory device is detachably attached. The image pickup device is connected to the accessory device from a notification channel used for notification from the image pickup device to the accessory device, a first data communication channel used for data transmission from the accessory device to the image pickup device, and an image pickup device. It has a camera communication unit that provides three channels composed of a second data communication channel used for data transmission to the accessory device, and a camera control unit that performs data communication with the accessory device via the camera communication unit. .. The camera control unit gives the accessory device a transmission request as the above notification via the notification channel, and receives the transmission request for the accessory information that changes with time to the accessory device via the second data communication channel. A specific command for acquiring accessory information at a time of 1 or at a second time acquired based on the first time is transmitted to the accessory device, and the accessory is transmitted via the first data communication channel. It is characterized by receiving accessory information at a first or second time from the device.

An imaging system including the imaging device and the accessory device also constitutes another aspect of the present invention.

Further, in the control method of the accessory device as another aspect of the present invention, the accessory device is given a first time when the transmission request is received in response to the transmission request received from the image pickup device via the notification channel. Acquired and acquired at the first time of the accessory information that changes with time or based on the first time in response to receiving a specific command from the image pickup apparatus via the second data communication channel. It is characterized in that the accessory information at the second time is acquired and the accessory information is transmitted to the image pickup apparatus via the first data communication channel.

Further, a method of controlling an imaging device as another aspect of the present invention causes the imaging device to give a transmission request to the accessory device via a notification channel and to the accessory device via a second data communication channel. Of the accessory information that changes with time, the accessory device is given a specific command for acquiring the accessory information at the first time when the transmission request is received or at the second time acquired based on the first time. A control method comprising transmitting and receiving accessory information at a first or second time from an accessory device via a first data communication channel.

According to the present invention, in an interchangeable lens camera system, processing such as calculation and control can be performed using information in which the timings of the accessory device and the image pickup device are accurately synchronized.

The block diagram which shows the structure of the camera system which is Example 1 of this invention. The block diagram which shows the communication circuit in Example 1. FIG. The figure which shows the waveform of the signal exchanged between a camera body and an interchangeable lens in Example 1. FIG. The figure which shows the communication timing between a camera body and an interchangeable lens in Example 1. FIG. The flowchart which shows the process performed in the camera body in Example 1. FIG. FIG. 5 is a flowchart showing another process performed by the camera body in the first embodiment. The flowchart which shows the process performed by the interchangeable lens in Example 1. FIG. FIG. 5 is a flowchart showing another process performed by the interchangeable lens in the first embodiment. The flowchart which shows the process performed in the camera body in Example 2 of this invention. The flowchart which shows the process performed by the interchangeable lens in Example 2.

Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows a configuration of an imaging system (hereinafter referred to as a camera system) including a camera body 200 as an imaging device according to a first embodiment of the present invention and an interchangeable lens 100 as an accessory device detachably attached thereto. Is shown.

The camera body 200 and the interchangeable lens 100 transmit control commands and internal information via their respective communication units, which will be described later. In addition, each communication unit supports multiple communication formats, and by switching to the same communication format in synchronization with each other according to the type of data to be communicated and the communication purpose, the optimum communication format for various situations It is possible to select.

First, a specific configuration of the interchangeable lens 100 and the camera body 200 will be described. The interchangeable lens 100 and the camera body 200 are mechanically and electrically connected via a mount 300, which is a coupling mechanism. The interchangeable lens 100 acquires power from the camera body 200 via a power supply terminal (not shown) provided on the mount 300, and supplies power necessary for operation to various actuators and lens microcomputer 111 described later. Further, the interchangeable lens 100 and the camera body 200 communicate with each other via a communication terminal portion (shown in FIG. 2) provided on the mount 300.

The interchangeable lens 100 has an imaging optical system. The imaging optical system includes a field lens 101, a variable magnification lens 102 for variable magnification, an aperture unit 114 for adjusting the amount of light, an image shake correction lens 103, and a focus lens 104 for adjusting the focus, in order from the subject OBJ side. including.

The variable magnification lens 102 and the focus lens 104 are held by lens holding frames 105 and 106, respectively. The lens holding frames 105 and 106 are movably guided in the optical axis direction (indicated by a broken line in the figure) by a guide shaft (not shown), and are driven in the optical axis direction by stepping motors 107 and 108, respectively. The stepping motors 107 and 108 move the variable magnification lens 102 and the focus lens 104 in synchronization with the drive pulse, respectively.

The image shake correction lens 103 moves in a direction orthogonal to the optical axis of the image pickup optical system to reduce image shake caused by camera shake or the like.

The lens microcomputer (hereinafter referred to as a lens microcomputer) 111 is an accessory control unit that controls the operation of each part in the interchangeable lens 100. The lens microcomputer 111 receives a control command transmitted from the camera body 200 and receives a lens data transmission request via the built-in lens communication unit 112. The lens microcomputer 111 performs lens control corresponding to a control command, and transmits lens data corresponding to a transmission request to the camera body 200 via the lens communication unit 112. The lens microcomputer 111 performs an operation related to communication with the camera body 200 (camera microcomputer 205 described later) according to a communication control program as a computer program.

Further, the lens microcomputer 111 outputs a drive signal to the zoom drive circuit 119 and the focus drive circuit 120 in response to commands related to scaling and focusing among control commands, and drives the stepping motors 107 and 108. As a result, zoom processing for controlling the variable magnification operation by the variable magnification lens 102 and AF (autofocus) processing for controlling the focus adjustment operation by the focus lens 104 are performed.

The interchangeable lens 100 has a manual focus ring (not shown) that can be rotated by the user, and a focus encoder that detects the amount of rotation of the manual focus ring. The lens microcomputer 111 moves the focus lens 104 by driving the stepping motor 108 in the focus drive circuit 120 according to the rotation operation amount of the manual focus ring detected by the focus encoder. As a result, MF (manual focus) is performed.

The diaphragm unit 114 includes diaphragm blades 114a and 114b. The states of the diaphragm blades 114a and 114b are detected by the Hall element 115 and input to the lens microcomputer 111 via the amplifier circuit 122 and the A / D conversion circuit 123. The lens microcomputer 111 outputs a drive signal to the aperture drive circuit 121 based on the input signal from the A / D conversion circuit 123 to drive the aperture actuator 113. As a result, the light amount adjusting operation by the aperture unit 114 is controlled.

Further, the interchangeable lens 100 has a runout sensor (hereinafter referred to as a gyro sensor) 129 configured by a vibration gyro or the like. The lens microcomputer 111 drives an anti-vibration actuator (voice coil motor, etc.) 126 via an anti-vibration drive circuit 125 according to the runout (angular velocity) detected by the gyro sensor 129. As a result, vibration isolation processing is performed to control the movement of the image shake correction lens 103. Further, the lens microcomputer 111 controls the movement of the image shake correction lens 103 while communicating with the camera microcomputer 205 as described later when a panning shot of a moving subject is taken while panning the camera system. Assists in panning.

The timer 130 provided on the interchangeable lens 100 is a free-run timer and counts the time with microsecond accuracy. Further, the lens memory (accessory storage unit) 128 provided in the interchangeable lens 100 is composed of a rewritable volatile memory, and temporarily holds data necessary for the lens microcomputer 111 to perform control. The lens microcomputer 111 stores the angular velocity acquired through the gyro sensor 129 and the time acquired from the timer 130 in association with each other in the lens memory 128.

The camera body 200 displays an image sensor 201 such as a CCD sensor or a CMOS sensor, an A / D conversion circuit 202, a signal processing circuit 203, a recording unit 204, and a camera microcomputer (hereinafter referred to as a camera microcomputer) 205. It has a part 206.

The image sensor 201 photoelectrically converts the subject image formed by the image pickup optical system in the interchangeable lens 100 and outputs an image pickup signal (analog signal) as an electric signal. The A / D conversion circuit 202 converts the analog image pickup signal from the image pickup element 201 into a digital image pickup signal. The signal processing circuit 203 performs various image processing on the digital image pickup signal from the A / D conversion circuit 202 to generate a video signal. The signal processing circuit 203 also generates focus information indicating the contrast state (focus state of the imaging optical system) of the subject image and luminance information indicating the exposure state from the video signal. The signal processing circuit 203 outputs a video signal to the display unit 206, and the display unit 206 displays the video signal as a live view image used for confirming a composition, a focus state, or the like. Further, the signal processing circuit 203 outputs a video signal to the recording unit 204, and the recording unit 204 records the video signal.

Further, the signal processing circuit 203 generates a vertical synchronization signal at each timing at which the image sensor 201 performs photoelectric conversion (charge accumulation) of the subject image and inputs it to the camera microcomputer 205. The camera microcomputer 205 acquires the time when half of the charge accumulation period as the exposure period of the image sensor 201 elapses from the input time of the vertical synchronization signal as the center time of the charge accumulation period (hereinafter referred to as the accumulation center time). .. Note that the camera microcomputer 205 may acquire the storage center time by inputting a signal indicating the storage center time to the camera microcomputer 205 by the signal processing circuit 203. The timer 209 provided in the camera body 200 is a free-run timer, and counts the time with microsecond accuracy.

The camera memory (camera storage unit) 210 is composed of a rewritable volatile memory, stores a digital image pickup signal obtained by the image sensor 201 and a video signal generated by the image processing circuit 203, and receives the image signal from the lens microcomputer 111. Stores the lens data. Further, the camera memory 210 temporarily holds data necessary for the camera microcomputer 205 to perform control.

The camera microcomputer 205 as a camera control unit controls the camera body 200 in response to an input from the camera operation unit 207 including an imaging instruction switch (not shown), various setting switches, and the like. Further, the camera microcomputer 205 transmits a control command related to the variable magnification operation of the variable magnification lens 102 to the lens microcomputer 111 in response to an operation of a zoom switch (not shown) via the built-in camera communication unit 208. Further, the camera microcomputer 205 transmits a control command related to the light amount adjusting operation of the aperture unit 114 according to the luminance information and the focus adjusting operation of the focus lens 104 according to the focus information to the lens microcomputer 111 via the camera communication unit 208. .. The camera microcomputer 205 performs an operation related to communication with the lens microcomputer 111 according to a communication control program as a computer program.

Next, a communication circuit configured between the camera body 200 (camera microcomputer 205) and the interchangeable lens 100 (lens microcomputer 111) and communication performed between them will be described with reference to FIG. The camera microcomputer 205 has a function of managing communication settings with the lens microcomputer 111 and a function of notifying the lens microcomputer 111 of a transmission request or the like. Further, the lens microcomputer 111 has a function of generating lens data and a function of transmitting the lens data.

The camera microcomputer 205 has a camera communication interface circuit 208a, and the lens microcomputer 111 has a lens communication interface circuit 112a. The camera microcomputer 205 (camera data transmission / reception unit 208b) and the lens microcomputer 111 (lens data transmission / reception unit 112b) include a communication terminal unit (indicated by three squares in the figure) provided on the mount 300 and the communication interface circuits 208a and 112a. Communicate via. In this embodiment, the camera microcomputer 205 and the lens microcomputer 111 perform (three-wire type) pace-synchronized serial communication using three channels. The camera data transmission / reception unit 208b and the camera communication interface circuit 208a constitute the camera communication unit 112, and the lens data transmission / reception unit 112b and the lens communication interface circuit 112a constitute the lens communication unit 112 as an accessory communication unit.

The above three channels are composed of a transmission request channel as a notification channel, a first data communication channel, and a second data communication channel. The transmission request channel is used for notification of a lens data transmission request (transmission instruction) from the camera microcomputer 205 to the lens microcomputer 111, a communication setting switching request (switching instruction) described later, and the like. Notification on the transmission request channel is performed by switching the signal level (voltage level) on the transmission request channel between High (first level) and Low (second level). In the following description, the signal supplied to the transmission request channel is referred to as a transmission request signal RTS.

The first data communication channel is used for transmitting lens data from the lens microcomputer 111 to the camera microcomputer 205. In the following description, the lens data (accessory data) transmitted as a signal from the lens microcomputer 111 to the camera microcomputer 205 in the first data communication channel is referred to as a lens data signal DLC. The second data communication channel is used for transmitting camera data from the camera microcomputer 205 to the lens microcomputer 111. In the following description, the camera data transmitted as a signal from the camera microcomputer 205 to the lens microcomputer 111 in the second data communication channel is referred to as a camera data signal DCL.

The transmission request signal RTS is transmitted from the camera microcomputer 205 as the communication master to the lens microcomputer 111 as the communication slave. The camera data signal DCL includes a control command, a transmission request command, and the like from the camera microcomputer 205 to the lens microcomputer 111. The lens data signal DLC includes various data transmitted from the lens microcomputer 111 to the camera microcomputer 205. The camera microcomputer 205 and the lens microcomputer 111 set the communication speed in advance, and transmit and receive at the communication bit rate according to this setting. The communication bit rate indicates the amount of data that can be transferred per second, and the unit is bps (bits per second). The camera microcomputer 205 and the lens microcomputer 111 communicate with each other by a full-duplex communication method (full duplex method) in which transmission and reception are performed.

The procedure of communication between the camera microcomputer 205 and the lens microcomputer 111 will be described with reference to FIG. FIG. 3 shows the waveform of a communication signal of one frame, which is the minimum communication unit. The breakdown of the data format of one frame is partially different between the camera data signal DCL and the lens data signal DLC.

First, the data format of the lens data signal DLC will be described. The lens data signal DLC of one frame is composed of a data frame in the first half and a BUSY frame following the data frame as a major division. The signal level of the lens data signal DLC is maintained at High in the non-transmission state in which no data is transmitted.

In order to notify the camera microcomputer 205 of the start of transmission of one frame of the lens data signal DLC, the lens microcomputer 111 sets the signal level of the lens data signal DLC to Low for a 1-bit period. This 1-bit period is called the start bit ST, and the data frame is started from this bit. Subsequently, the lens microcomputer 111 transmits 1-byte lens data in an 8-bit period from the next 2nd bit to the 9th bit. The data bit array is in the MSB first format, starting with the most significant data D7, followed by data D6, data D5, and ending with the lowest data D0. Then, the lens microcomputer 111 adds 1-bit parity information (PA) to the 10th bit, and sets the signal level of the lens data signal DLC during the period of the stop bit SP indicating the end of one frame to High. As a result, the data frame period started from the start bit ST ends.

Subsequently, the lens microcomputer 111 adds a BUSY frame after the stop bit SP. The BUSY frame represents the period of the communication standby request BUSY notified from the lens microcomputer 111 to the camera microcomputer 205. The lens microcomputer 111 holds the signal level of the lens data signal DLC in Low until the communication standby request BUSY is released.

A method of identifying the presence / absence of BUSY notification performed by the camera microcomputer 205 will be described. The signal waveform shown in FIG. 3 includes bit positions B1 and B2. The camera microcomputer 205 selects one of the bit positions of B1 and B2 as the BUSY identification position P for identifying the presence / absence of the BUSY notification. As described above, in this embodiment, the data format in which the BUSY identification position P is selected from the bit positions of B1 and B2 is adopted. This makes it possible to deal with the problem that the processing time from the transmission of the data frame of the lens data signal DLC to the determination of the BUSY notification (Low of the DLC) differs depending on the processing performance of the lens microcomputer 111.

Whether the BUSY identification position P is the bit position of B1 or the bit position of B2 is determined by communication between the camera microcomputer 205 and the lens microcomputer 111 before data communication is performed. It is not necessary to fix the BUSY identification position P to either the bit position of B1 or B2, and it may be changed according to the processing capacity of both microcomputers 205 and 111.

Next, the data format of the camera data signal DCL will be described. In the data format of the camera data signal DCL of one frame, the specifications of the data frame are the same as those of the lens data signal DLC. However, unlike the lens data signal DLC, the camera data signal DCL is prohibited from adding a BUSY frame.

Next, the procedure of communication between the camera microcomputer 205 and the lens microcomputer 111 will be described. When an event for starting communication with the lens microcomputer 111 occurs, the camera microcomputer 205 sets the level of the transmission request signal RTS to Low (hereinafter, referred to as asserting the transmission request signal RTS) with respect to the lens microcomputer 111. Notify the transmission request. When the lens microcomputer 111 detects a transmission request by the transmission request signal RTS Low, the lens microcomputer 111 generates a lens data signal DLC to be transmitted to the camera microcomputer 205. Then, when the lens data signal DLC is ready to be transmitted, the transmission of the lens data signal DLC of one frame on the first data communication channel is started. Here, the lens microcomputer 111 starts transmitting the lens data signal DLC within a set time set mutually between the camera microcomputer 205 and the lens microcomputer 111 from the time when the transmission request signal RTS becomes Low. That is, it is strict that it is necessary to determine the lens data to be transmitted by the time when the first clock pulse is input between the time when the transmission request signal RTS becomes Low and the start of transmission of the lens data signal DLC. There are no restrictions.

Next, the camera microcomputer 205 sets the level of the transmission request signal RTS according to the detection of the start bit ST (start of reception of the lens data signal DLC), which is the first bit of the data frame of the lens data signal DLC received from the lens microcomputer 111. Return to High. Hereinafter, returning the level of the transmission request signal RTS to High is referred to as negating the transmission request signal RTS. As a result, the transmission request is canceled and the transmission of the camera data signal DCL on the second data communication channel is started. It does not matter which of the negate of the transmission request signal RTS and the start of transmission of the camera data signal DCL comes first, and these may be performed until the reception of the data frame of the lens data signal DLC is completed.

The lens microcomputer 111 that has transmitted the data frame of the lens data signal DLC adds the BUSY frame to the lens data signal DLC when it is necessary to notify the camera microcomputer 205 of the communication standby request BUSY. The camera microcomputer 205 monitors the presence / absence of notification of the communication standby request BUSY, and while the communication standby request BUSY is notified, it is prohibited to assert the transmission request signal RTS for the next transmission request. The lens microcomputer 111 executes necessary processing during the period in which the communication from the camera microcomputer 205 is made to wait by the communication standby request BUSY, and cancels the communication standby request BUSY after the next communication preparation is completed. The camera microcomputer 205 is permitted to assert the transmission request signal RTS for the next transmission request, provided that the communication standby request BUSY is released and the transmission of the data frame of the camera data signal DCL is completed. ..

As described above, in this embodiment, the lens microcomputer 111 sends the lens data signal DLC data frame to the camera microcomputer 205 in response to the assertion of the transmission request signal RTS triggered by the communication start event in the camera microcomputer 205. Start sending. Then, the camera microcomputer 205 starts transmitting the data frame of the camera data signal DCL to the lens microcomputer 111 in response to detecting the start bit ST of the lens data signal DLC. Here, the lens microcomputer 111 adds a BUSY frame after the data frame of the lens data signal DLC for the communication standby request BUSY as needed, and then cancels the communication standby request BUSY to perform communication processing of one frame. Complete. By this communication process, 1 byte of data is transmitted to and received from each other between the camera microcomputer 205 and the lens microcomputer 111.

Next, the panning assist performed by the camera system of this embodiment will be described. FIG. 4 shows the communication timing between the camera microcomputer 205 and the lens microcomputer 111 in the panning assist and the acquisition timing of the angular velocity from the gyro sensor 129 by the lens microcomputer 111. The storage period 401 indicates the charge storage period for each image pickup frame in the image pickup device 201. The image sensor 201 accumulates electric charge by using a vertical synchronization signal VD generated at a predetermined image frame cycle (here, 1/30 second) as a trigger. That is, the timing at which the vertical synchronization signal VD is generated is the start timing of charge accumulation of the image sensor 201. Further, here, the length of the charge accumulation period (shutter speed) is set to 1/50 second. Each storage period 401 is given a frame identifier which is an identifier for distinguishing the storage period 401 (that is, the imaging frame) before and after the storage period 401.

The camera microcomputer 205 transmits a storage center notification 402 to the lens microcomputer 111 for each storage center time, which is the center time of the charge storage period (storage period 401) of the image sensor 201 described above, by transmitting a camera data signal DCL. The storage center notification 402 includes information on the delay time from the storage center time, which is the time corresponding to the storage center time generated by the BUSY notification from the lens microcomputer 111, and a frame for identifying the current storage period (imaging frame). Includes identifiers. The camera microcomputer 205 can acquire the storage center time from the timer 209. The storage center time (predetermined time) acquired by the camera microcomputer 205 is referred to as the camera storage center time in the following description.

In the interchangeable lens 100, the gyro sensor 129 acquires the angular velocity in a sampling cycle of 4 kHz. The lens microcomputer 111 holds the acquired angular velocity and the time acquired from the timer 130 at each timing (hereinafter referred to as angular velocity sampling timing) 404 of acquiring the angular velocity in this sampling cycle in the lens memory 128.

When the lens microcomputer 111 receives the storage center notification 402, the lens microcomputer 111 calculates the lens storage center time using the RTS time described later and the delay time included in the storage center notification 402. Then, the lens microcomputer 111 calculates the angular velocity (accessory information: hereinafter, referred to as the accumulated central angular velocity) at the lens storage center time by the linear complement method using the angular velocity and the time held in the lens memory 128. Further, the lens microcomputer 111 associates the calculated accumulated central angular velocity with the received frame identifier and holds them in the lens memory 128. The camera microcomputer 205 sets the angular velocity request 403 for requesting the acquisition (transmission) of the angular velocity in the camera data signal DCL of the camera communication unit 208 and starts communication after a predetermined time after transmitting the storage center notification 402. The angular velocity request 403 is made to the lens microcomputer 111. Upon receiving the angular velocity request, the lens microcomputer 111 transmits the accumulated central angular velocity and the frame identifier associated therewith (hereinafter referred to as the angular velocity detection frame identifier) to the camera microcomputer 205 by the lens data signal DLC.

The camera microcomputer 205 acquires the amount of movement (camera information) of the subject image on the image signal generated from the image pickup signal obtained by using the image pickup element 201, that is, on the image pickup surface of the image pickup element 201, for each image pickup frame. (calculate. The calculated movement amount of the subject image on the imaging surface corresponds to the movement amount of the image pickup frame at the accumulation center time.

Then, the camera microcomputer 205 calculates the panning correction amount (control information) in the current imaging frame from the moving amount of the subject image on the imaging surface and the accumulated central angular velocity acquired from the lens microcomputer 111. The calculation (generation) of this panning correction amount corresponds to the camera processing related to imaging. At this time, in the camera microcomputer 205, the frame identifier of the charge accumulation period (hereinafter referred to as the movement amount calculation frame identifier) for which the movement amount of the subject image on the imaging surface is calculated and the angular velocity detection frame identifier received from the lens microcomputer 111 are mutually arranged. Check if they match. The camera microcomputer 205 calculates the panning correction amount in the current imaging frame if they match each other, and if they do not match, the result of the panning correction amount calculated in the previous imaging frame is used in the current imaging frame. Take over to.

When the camera microcomputer 205 receives a release request from the user through the camera operation unit 207, the camera microcomputer 205 transmits a panning correction amount notification including the calculated panning correction amount to the lens microcomputer 111. The lens microcomputer 111 receives the panning correction amount notification, and drives the anti-vibration actuator 126 via the anti-vibration drive circuit 125 according to the panning correction amount included in the notification. In this way, the lens microcomputer 111 controls the movement of the image shake correction lens 103 for panning assist.

The flowchart of FIG. 5 shows the flow of processing performed by the camera microcomputer 205 in order for the lens microcomputer 111 to recognize the accurate storage center time. The camera microcomputer 205 executes this process and other processes described later according to a control program which is a computer program.

When the camera microcomputer 205 acquires the storage center time based on the input of the vertical synchronization signal from the signal processing circuit 203 or directly from the signal processing circuit 203, the camera microcomputer 205 proceeds to step S501. In step S501, the camera microcomputer 205 acquires the current time from the timer 209, and holds this in the camera memory 210 as the camera storage center time, which is the time at the time of acquisition of the storage center time.

Next, in step S502, the camera microcomputer 205 confirms whether or not the BUSY notification is given in the lens data signal DLC. If the BUSY notification is given, this confirmation is performed again, and if the BUSY notification is canceled (that is, waiting for the end of reception of the lens data signal DLC), the process proceeds to step S503.

In step S503, the camera microcomputer 205 acquires the current time from the timer 209, and the difference between this current time, that is, the time when the BUSY notification is canceled and the camera storage center time held in the camera memory 210 in step S501. Calculate (delay time). Then, the camera microcomputer 205 sets the calculated delay time and the frame identifier for identifying the current imaging frame in the camera data signal DCL.

Then, in step S504, the camera microcomputer 205 asserts the transmission request signal RTS to cause the lens microcomputer 111 to start communication. In step S505, the camera microcomputer 205 waits for the start bit ST of the lens data signal DLC transmitted from the lens microcomputer 111. The lens data signal DLC at this time corresponds to mere response data that does not include significant information.

The camera microcomputer 205 that has detected the start bit ST of the lens data signal DLC transmits the camera data signal DCL set in step S503 to the lens microcomputer 111 in step S506. That is, the camera microcomputer 205 transmits a storage center notification (delay time from the camera storage center time and a frame identifier) as a specific command to the lens microcomputer 111 as a camera data signal DCL. The detection of the start bit ST of the lens data signal DLC by the camera microcomputer 205 and the start of transmission of the storage center notification are performed without time delay from the cancellation of the BUSY notification by the lens microcomputer 111 and the assertion of the transmission request signal RTS by the camera microcomputer 205. Therefore, the delay time can be regarded as the delay time from the camera storage center time to the time when the transmission / reception of the storage center notification is started by asserting the transmission request signal RTS.

Then, in step S507, the camera microcomputer 205 receives the lens data signal DLC from the lens microcomputer 111. In this embodiment, the lens data signal DLC received at this time does not include significant information.

Next, the process performed by the camera microcomputer 205 when acquiring the angular velocity from the lens microcomputer 111 will be described with reference to the flowchart of FIG. When the camera microcomputer 205 acquires the movement amount of the subject image on the image pickup surface (hereinafter referred to as the movement amount of the subject in the current image pickup frame) from the video signal obtained by using the image pickup element 201, the camera microcomputer 205 proceeds to step S901.

In step S901, the camera microcomputer 205 transmits the angular velocity request to the lens microcomputer 111 by setting the angular velocity request in the camera data signal DCL of the camera communication unit 208 and starting the communication. Next, in step S902, the camera microcomputer 205 receives the accumulated central angular velocity from the lens microcomputer 111 by the lens data signal DLC. At this time, the lens data signal DLC includes an angular velocity detection frame identifier associated with the accumulated central angular velocity.

Next, in step S903, the camera microcomputer 205 confirms whether the movement amount calculation frame identifier associated with the subject movement amount in the current imaging frame matches the angular velocity detection frame identifier received from the lens microcomputer 111 in step S902. To do. If they match, the camera microcomputer 205 proceeds to step S904, and if they do not match, the camera microcomputer 205 proceeds to step S905.

In step S904, the camera microcomputer 205 calculates the panning correction amount in the current imaging frame from the amount of movement of the subject in the current imaging frame and the accumulated central angular velocity received in step S902. Then, this panning correction amount is held in the camera memory 210 together with the storage center time.

On the other hand, in step S905, the camera microcomputer 205 reads the panning correction amount calculated and held for the previous imaging frame from the camera memory 210. Then, the previous panning correction amount is held in the camera memory 210 as the panning correction amount in the current imaging frame together with the accumulation center time in the current imaging frame.

Next, in step S906, the camera microcomputer 205 determines whether or not there is a release request from the user through the camera operation unit 207. When there is a release request, in step S907, the camera microcomputer 205 transmits a panning correction amount notification including the panning correction amount held in the camera memory 210 in step S904 or S905 to the lens microcomputer 111 by the camera data signal DCL. To do. Then, this process ends.

Next, the process performed by the lens microcomputer 111 in this embodiment will be described with reference to the flowchart of FIG. 7. The lens microcomputer 111 executes this process and other processes described later according to a control program as a computer program.

When the lens microcomputer 111 detects the assertion of the communication request signal RTS by the camera microcomputer 205 in step S504 of FIG. 5 in step S601, the lens microcomputer 111 proceeds to step S602. In step S602, the lens microcomputer 111 acquires the current time from the timer 130 and holds it in the lens memory 128 as the RTS time (first time) which is the time when the communication request signal RTS is asserted.

Next, in step S603, the lens microcomputer 111 confirms whether there is any processing that should be prioritized other than the panning assist. The processing to be prioritized includes the above-mentioned zoom processing and AF processing. If there is a process to be prioritized, the lens microcomputer 111 returns to step S603, and if there is no process to be prioritized, the lens microcomputer 111 proceeds to step S604.

In step S604, the lens microcomputer 111 transmits the lens data signal DLC to the camera microcomputer 205. The lens data signal DLC at this time is the response data received by the camera microcomputer 205 in step S505 of FIG. 5, and does not include significant information.

Next, in step S605, the lens microcomputer 111 receives the camera data signal DCL from the camera microcomputer 205. Then, in step S606, the lens microcomputer 111 interprets the command included in the received camera data signal DCL. The commands included in the camera data signal DCL include a focus drive command, a storage center notification, and the like, and are composed of commands and their arguments. The argument of the storage center notification consists of the delay time from the camera storage center time and the frame identifier.

Next, in step S607, the lens microcomputer 111 determines whether or not the received command is a storage center notification as a specific command. If the notification is centered on storage, the lens microcomputer 111 proceeds to step S608, and if not, ends this process.

In step S608, the lens microcomputer 111 acquires the lens storage center time (second time) by subtracting the delay time received in step S606 from the RTS time held in the lens memory 128. As described above, the delay time can be regarded as the delay time from the camera storage center time to the time when the lens microcomputer 111 starts receiving the storage center notification, and the time when the storage center notification reception starts is the RTS time. Corresponds to. Therefore, the lens storage center time calculated using these RTS times and the delay time corresponds to the camera storage center time.

Next, in step S609, the lens microcomputer 111 calculates the accumulated central angular velocity by the linear complement method using a plurality of combinations of the angular velocity held in the lens memory 128 and the time when the angular velocity is acquired for each angular velocity sampling timing. To do. Further, the lens microcomputer 111 holds the calculated accumulated central angular velocity and the frame identifier received in step S606 (which becomes the angular velocity detection frame identifier) in association with each other in the lens memory 128. Then, this process ends.

Next, using the flowchart of FIG. 8, a process performed by the lens microcomputer 111 when transmitting the accumulated central angular velocity to the camera microcomputer 205 will be described. When the lens microcomputer 111 receives the angular velocity request from the camera data signal DCL from the camera microcomputer 205 in step S1001, the lens microcomputer 111 proceeds to step S1002.

In step S1002, the lens microcomputer 111 reads the accumulated central angular velocity and the angular velocity detection frame identifier associated therewith from the lens memory 128, and deletes the accumulated central angular velocity and the angular velocity detection frame identifier after reading from the lens memory 128.

Next, in step S1003, the lens microcomputer 111 transmits the accumulated central angular velocity and the angular velocity detection frame identifier read in step S1002 to the camera microcomputer 205 by the lens data signal DLC.

In the present embodiment described above, the camera microcomputer 205 transmits the delay time from the camera storage center time by the BUSY frame added to the lens data signal DLC to the lens microcomputer 111 by the camera data signal DCL. By subtracting the camera storage center time from the RTS time, the lens microcomputer 111 can acquire the lens storage center time corresponding to the accurate storage center time in the camera body 200. As a result, even if a BUSY frame is added to the lens data signal DLC or a transmission delay of the lens data signal DLC occurs, the lens microcomputer 111 can acquire an accurate accumulation center time in the camera body 200.

As a result, in the interchangeable lens 100, it is possible to obtain the angular velocity (accumulated central angular velocity) at the time when the amount of movement of the subject on the imaging surface is acquired by the camera body 200. That is, it is possible to accurately synchronize the acquisition timing of the subject image movement amount on the image pickup surface of the camera body 200 with the acquisition timing of the angular velocity of the interchangeable lens 100. Therefore, it is possible to avoid a decrease in the accuracy of the panning assist due to a difference between the acquisition time of the subject movement amount on the imaging surface and the acquisition time of the angular velocity. In other words, high-precision (good) panning assist can be performed.

Next, Example 2 of the present invention will be described. In the first embodiment, the case where the camera microcomputer 205 cannot request communication from the lens microcomputer 111 (cannot assert the transmission request signal RTS) while the lens microcomputer 111 is transmitting the BUSY notification has been described. On the other hand, in this embodiment, the case where the camera microcomputer 205 can assert the transmission request signal RTS even while the lens microcomputer 111 is transmitting the BUSY notification will be described.

The configurations of the interchangeable lens 100 and the camera body 200 in this embodiment are the same as those in the first embodiment, and common components are designated by the same reference numerals as those in the first embodiment.

The processing performed by the camera microcomputer 205 in this embodiment will be described with reference to the flowchart of FIG. When the camera microcomputer 205 acquires the storage center time based on the input of the vertical synchronization signal from the signal processing circuit 203 or directly from the signal processing circuit 203, the camera microcomputer 205 proceeds to step S701. In step S701, the camera microcomputer 205 asserts the transmission request signal RTS and causes the lens microcomputer 111 to start communication regardless of whether or not the lens microcomputer 111 is transmitting the BUSY notification.

Then, the camera microcomputer 205 that has detected the start bit ST of the lens data signal DLC transmitted from the lens microcomputer 111 in step S703 transmits a storage center notification as a specific command to the lens microcomputer 111 as the camera data signal DCL. In this embodiment, the camera microcomputer 205 asserts the transmission request signal RTS immediately after acquiring the storage center time, and in response to the assertion of the transmission request signal RTS, in response to the detection of the start bit ST of the lens data signal DLC transmitted from the lens microcomputer 111. Send a store center notification. The storage center notification is performed without a time delay from the assertion (acquisition of the storage center time) of the transmission request signal RTS. Therefore, it can be considered that the storage center notification is performed at the same time as the camera storage center time.

Step S704 is the same as step S507 of FIG. 5 described in the first embodiment.

Next, the process performed by the lens microcomputer 111 in this embodiment will be described with reference to the flowchart of FIG. When the assertion of the communication request signal RTS by the camera microcomputer 205 in step S701 of FIG. 9 is detected in step S601, the process proceeds to step S802. In step S802, the lens microcomputer 111 acquires the current time from the timer 130 and holds it in the lens memory 128 as the RTS time (first time) which is the time when the communication request signal RTS is asserted. In this embodiment, as described above, the transmission request signal RTS is asserted as soon as the camera microcomputer 205 acquires the storage center time (step S701 in FIG. 9). Therefore, the RTS time when the lens microcomputer 111 detects this assert is the lens storage center time corresponding to the time when the camera microcomputer 205 acquires the storage center time (camera storage center time).

Subsequent steps S803 to S807 are the same as steps S603 to S607 of FIG. 7 described in the first embodiment.

If the command received from the camera microcomputer 205 in step S807 is the storage center notification as a specific command, the lens microcomputer 111 proceeds to step S808. In step S808, the lens microcomputer 111 uses a plurality of combinations of the angular velocity held in the lens memory 128 for each angular velocity sampling timing and the time when the angular velocity is acquired, and the angular velocity at the RTS time, that is, by the linear complement method. Calculates the central angular velocity of accumulation. Further, the lens microcomputer 111 holds the calculated angular velocity at the RTS time and the frame identifier received in step S806 (which becomes the angular velocity detection frame identifier) in association with each other in the lens memory 128. Then, this process ends.

Also in this embodiment, the camera microcomputer 205 performs the process described with reference to FIG. 6 in the first embodiment, and the lens microcomputer 111 performs the process described with reference to FIG. 8 in the first embodiment. As a result, panning assist is performed.

In the present embodiment described above, when the camera microcomputer 205 acquires the storage center time, the transmission request signal RTS is immediately asserted even if the BUSY notification is transmitted from the lens microcomputer 111. Therefore, the lens microcomputer 111 obtains the RTS time at which the transmission request signal RTS is asserted by the camera microcomputer 205 as the lens storage center time. As a result, even if a BUSY frame is added to the lens data signal DLC or a transmission delay of the lens data signal DLC occurs, the lens microcomputer 111 can acquire an accurate accumulation center time in the camera body 200. As a result, the acquisition timing of the subject image movement amount on the imaging surface of the camera body 200 and the acquisition timing of the angular velocity of the interchangeable lens 100 can be accurately synchronized, and high-precision (good) panning assist can be achieved. It can be carried out.

In each of the above embodiments, the case where the lens microcomputer 111 acquires angular velocity information as accessory information that changes with time has been described. However, the accessory information may be any information as long as it is information that changes with time, such as information on the position of the variable magnification lens 102, the focus lens 104, or the image shake correction lens 103. Further, although the case of performing panning assist has been described in each of the above embodiments, the communication described in each embodiment can be used even when performing processing such as calculation for control other than panning assist.
(Other Examples)
The present invention supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and one or more processors in the computer of the system or device reads and executes the program. It can also be realized by the processing to be performed. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.
Each of the above-described examples is only a representative example, and various modifications and changes can be made to each of the examples in carrying out the present invention.

100 Interchangeable lens 111 Lens microcomputer 129 Gyro sensor 200 Camera body 205 Camera microcomputer 201 Image sensor

Claims (17)

An accessory device that is removable and attached to the image pickup device.
A notification channel used for notification from the image pickup device to the accessory device, a first data communication channel used for data transmission from the accessory device to the image pickup device, and the image pickup device between the image pickup device and the image pickup device. An accessory communication unit provided with three channels including a second data communication channel used for data transmission from the accessory device to the accessory device.
An accessory control unit that performs data communication with the image pickup device via the accessory communication unit and acquires accessory information that changes with time.
Has a timer that counts the time
The accessory control unit
In response to receiving the transmission request as the notification from the imaging device via the notification channel, the first time at which the transmission request is received is acquired from the timer.
The accessory at the first time or at a second time acquired based on the first time in response to receiving a particular command from the imager via the second data communication channel. Get information,
An accessory device characterized in that the accessory information is transmitted to the image pickup device via the first data communication channel. The accessory control unit
In response to the transmission request, response data is transmitted to the image pickup apparatus via the first data communication channel, and the response data is transmitted.
The accessory device according to claim 1, wherein the image pickup device receives the specific command transmitted in response to the start of reception of the response data. The imaging device waits for the end of reception of the response data and gives the accessory device the transmission request.
The specific command includes information on a delay time from a predetermined time to giving the transmission request.
The accessory control unit acquires the second time corresponding to the predetermined time by subtracting the delay time from the first time, and acquires the accessory information at the second time. The accessory device according to claim 1 or 2. The accessory device according to claim 3, wherein the predetermined time is the central time of the exposure period for each imaging frame in the imaging device. The specific command includes a frame identifier for identifying an imaging frame in the imaging apparatus.
The accessory control unit according to any one of claims 1 to 4, wherein the accessory control unit transmits the accessory information at the first or second time in association with the frame identifier to the image pickup apparatus. Accessory device. It has a sensor that detects the angular velocity,
The accessory device according to any one of claims 1 to 5, wherein the accessory control unit acquires information on the angular velocity as the accessory information. An imaging device to which an accessory device is detachably attached.
Between the accessory device, a notification channel used for notification from the image pickup device to the accessory device, a first data communication channel used for data transmission from the accessory device to the image pickup device, and the image pickup device. A camera communication unit provided with three channels including a second data communication channel used for data transmission from the accessory device to the accessory device.
It has a camera control unit that performs data communication with the accessory device via the camera communication unit.
The camera control unit
A transmission request as the notification is given to the accessory device via the notification channel.
A second of the accessory information that changes with time to the accessory device via the second data communication channel, is acquired at the first time when the transmission request is received or based on the first time. the specific command for acquiring the accessory information at time, and transmitted to the accessory device,
An imaging device comprising receiving the accessory information at the first or second time from the accessory device via the first data communication channel. The camera control unit
Response data is received from the accessory device that has given the transmission request via the first data communication channel.
The imaging device according to claim 7, wherein the specific command is transmitted to the imaging device in response to the start of reception of the response data. Has a timer to count the time,
The camera control unit waits for the end of reception of the response data and gives the accessory device the transmission request.
The imaging device according to claim 7 or 8, wherein the specific command includes information on a delay time from a predetermined time acquired using the time from the timer to giving the transmission request to the accessory device. .. The imaging device according to claim 9, wherein the predetermined time is the central time of the exposure period for each imaging frame in the imaging device. The imaging device according to any one of claims 7 to 10, wherein the camera control unit performs camera processing related to imaging using the accessory information at the first or second time. The imaging device according to any one of claims 7 to 11, wherein the camera control unit acquires information on the angular velocity as the accessory information from the accessory device. The camera control unit acquires camera information related to imaging for each imaging frame, and holds the camera information in association with a frame identifier for identifying the imaging frame.
The specific command includes the frame identifier associated with the accessory information in the accessory device.
The imaging device according to any one of claims 7 to 10, wherein the camera control unit performs camera processing related to imaging by using the camera information and the accessory information whose frame identifiers match each other. .. The camera control unit
Information on the angular velocity is acquired from the accessory device as the accessory information, and information on the amount of movement of the subject image on the imaging surface is acquired as the camera information.
The imaging device according to claim 13, wherein the camera processing is performed using the information on the angular velocity and the information on the amount of movement. An imaging system that includes an imaging device and an accessory device that is detachably attached to the imaging device.
The imaging device and the accessory device have a notification channel used for notification from the imaging device to the accessory device, a first data communication channel used for data transmission from the accessory device to the imaging device, and the above. It has a camera communication unit and an accessory communication unit provided with three channels composed of a second data communication channel used for data transmission from the image pickup device to the accessory device.
The accessory device has an accessory control unit that performs data communication with the image pickup device via the accessory communication unit and acquires accessory information that changes with time, and a timer that counts the time.
The image pickup device has a camera control unit that performs data communication with the accessory device via the camera communication unit.
The accessory control unit
In response to receiving the transmission request as the notification from the imaging device via the notification channel, the first time at which the transmission request is received is acquired from the timer.
The accessory at the first time or at a second time acquired based on the first time in response to receiving a particular command from the imager via the second data communication channel. Get information,
The camera control unit
An imaging system comprising receiving the accessory information at the first or second time from the accessory device via the first data communication channel. An accessory device that is detachably attached to the image pickup device, and a notification channel used for notification from the image pickup device to the accessory device and data transmission from the accessory device to the image pickup device between the image pickup device and the image pickup device. It is a control method of an accessory device provided with three channels including a first data communication channel used for the above and a second data communication channel used for data transmission from the image pickup device to the accessory device.
To the accessory device
In response to receiving the transmission request as the notification from the imaging device via the notification channel, the first time when the transmission request is received is acquired.
Acquired at the first time or based on the first time of the accessory information that changes with time in response to receiving a specific command from the image pickup device via the second data communication channel. Get the accessory information at the second time
A control method comprising transmitting the accessory information to the image pickup apparatus via the first data communication channel. An image pickup device to which the accessory device is detachably mounted, and a notification channel used for notification from the image pickup device to the accessory device and data transmission from the accessory device to the image pickup device between the image pickup device and the accessory device. A method for controlling an imaging device, which is provided with three channels including a first data communication channel used in the above and a second data communication channel used for transmitting data from the imaging device to the accessory device.
In the image pickup device
The accessory device is made to give a transmission request as the notification via the notification channel.
A second of the accessory information that changes with time to the accessory device via the second data communication channel, is acquired at the first time when the transmission request is received or based on the first time. the specific command for acquiring the accessory information at time, is transmitted to the accessory device,
A control method comprising receiving the accessory information at the first or second time from the accessory device via the first data communication channel.