JP5725763B2 - Interchangeable lens and control method thereof, imaging apparatus and control method thereof - Google Patents

Description

  The present invention relates to an interchangeable lens that can be attached to an imaging apparatus and exchanges information by communication, and an imaging apparatus that can exchange lenses.

  Conventionally, synchronous communication using a clock signal has been adopted as a communication method between a camera and an interchangeable lens. FIG. 6 is a timing chart of communication signals between the camera and the interchangeable lens in synchronous serial communication. Patent Document 1 discloses the following technical contents. First, synchronous serial communication is performed at a first communication speed at which communication is possible even with an old type interchangeable lens. When the mounted interchangeable lens is determined to be a new lens according to the communication content, the communication is switched to synchronous serial communication at a higher second communication speed. In addition, it is also described that the communication terminal circuit is switched from an open drain type to a CMOS type suitable for high-speed communication when the communication speed is switched. According to this technology, it is possible to operate with a combination with an old type interchangeable lens even though the speed is low, and with a combination with a new type interchangeable lens, it is possible to realize an improvement in communication speed at a certain level.

Japanese Patent No. 3655804

  By the way, in the conventional synchronous serial communication, in order to set the data to be sent to the camera in the next communication by analyzing the data received by the lens between the communication, and to execute processing based on the received data A waiting time is provided. The state in which this waiting time has occurred is called Busy, and the lens does not accept communication from the camera during Busy. Therefore, no matter how fast the clock speed is increased, the microcomputer on the camera side communicates while waiting for the lens to release Busy, so there is a limit to the improvement in operation performance. On the other hand, the camera on the lens side frequently generates a communication interrupt from the camera, and each time a Busy signal is output and a communication interrupt process for cancellation must be preferentially performed. It becomes.

  An object of the present invention is to provide a camera and an interchangeable lens that can further improve the operation performance while supporting an old type interchangeable lens using a conventional communication system.

To achieve the above object, the interchangeable lens according to the present invention, there is provided a an interchangeable lens mounted on the imaging device, an optical member, the imaging device and for communicating the first lens terminal and the second A lens terminal, a drive control means for controlling the driving of the optical member, and a first data communication using the second lens terminal in synchronization with a clock signal received from the imaging device via the first lens terminal. And a second control mode for communicating data with the second lens terminal without synchronizing with a signal received from the imaging device, and a lens control for controlling the communication with the imaging device. and means, the lens control means, the first performs the image pickup device and the data communication in the communication mode, determine that the interchangeable lens in the imaging apparatus corresponding to the second communication mode After being, switching to the second communication mode, the lens control means, in said second communication mode, from the image pickup device data regarding the driving amount of the optical member through the second lens terminal receiving, based on the data relating to the driving of the optical member that receives, starts driving of the drive control means wherein the optical member in accordance with a predetermined pulse signal received from the imaging device via the first lens terminal It characterized that you control to.
Further, the interchangeable lens according to the present invention, there is provided a an interchangeable lens mounted on the imaging device, an optical member, a first lens terminal and the second lens terminal for communicating with the imaging device, the optical A drive control means for controlling the drive of the member; a first communication mode for performing data communication with the second lens terminal in synchronization with a clock signal received from the imaging device via the first lens terminal; A second communication mode in which data communication is performed at the first lens terminal without being synchronized with a signal received from the imaging device, and a lens control unit that controls communication with the imaging device; the lens control unit, after the first performs the image pickup device and the data communication in the communication mode, that the interchangeable lens in the imaging apparatus corresponding to the second communication mode has been determined, the first Switching the communication mode of said lens controller is in the second communication mode, via the first lens terminal receives data about the driving amount of the optical member from the imaging device, the optical member that receives based on the data relating to the driving of the control to Rukoto as the drive control means starts driving of the optical member in accordance with a predetermined pulse signal received from the imaging device via the second lens terminal Features.

An image pickup apparatus according to the present invention is an image pickup apparatus that can be mounted with an interchangeable lens including an optical member and a drive control unit that controls driving of the optical member, and is configured to communicate with the interchangeable lens. A first communication mode for communicating data with the second terminal in synchronization with a clock signal transmitted to the interchangeable lens via the first terminal; and A second communication mode in which data communication is performed at the second terminal without being synchronized with a signal to be transmitted, and a control unit that controls communication with the interchangeable lens, and the control unit includes: It said first performs the interchangeable lens data communication in a communication mode, switch to the second communication mode after the interchangeable lens is determined to be corresponding to the second communication mode, wherein, said Second communication In over de, after via the second terminal transmits data regarding the driving amount of the optical member to the interchangeable lens, the start of the driving of the first of said terminals to said drive control means via an optical member It is transmitted to the interchangeable lens a predetermined pulse signal instructing characterized Rukoto.
An image pickup apparatus according to the present invention is an image pickup apparatus that can be mounted with an interchangeable lens including an optical member and a drive control unit that controls driving of the optical member, and is configured to communicate with the interchangeable lens. A first communication mode for communicating data with the second terminal in synchronization with a clock signal transmitted to the interchangeable lens via the first terminal; and A second communication mode in which data communication is performed at the first terminal without being synchronized with a signal to be transmitted, and a control unit that controls communication with the interchangeable lens, and the control unit includes: It said first performs the interchangeable lens data communication in a communication mode, switch to the second communication mode after the interchangeable lens is determined to be corresponding to the second communication mode, wherein, said Second communication In over de, start of the data regarding the driving amount of the first of the optical member via the terminal after sending the interchangeable lens, the driving of the optical member to the drive control means via said second terminal It is transmitted to the interchangeable lens a predetermined pulse signal instructing characterized Rukoto.

  According to the present invention, it is possible to provide a camera and an interchangeable lens that can further improve the operation performance while supporting an old type interchangeable lens using a conventional communication method.

The figure showing the circuit structure of the camera which implemented this invention, and an interchangeable lens Image timing chart of imaging circuit Microcomputer circuit block diagram Block diagram of communication control circuit Lens driving operation flowchart by the camera and the interchangeable lens according to the present invention Timing chart of communication signal between camera and interchangeable lens in synchronous communication system Timing chart of communication signals between camera and interchangeable lens in asynchronous communication system The timing chart figure of the communication signal of the camera which implemented this invention, and an interchangeable lens Operation flowchart of camera-side microcomputer embodying the present invention Operational flow chart of lens-side microcomputer embodying the present invention Operation flowchart of camera-side microcomputer in synchronous communication system Operation flowchart of lens side microcomputer in synchronous communication system Image timing chart of the imaging circuit during video recording Operation timing chart of imaging circuit control signal and lens drive communication during moving image recording in comparative example

Example 1
FIG. 1 is a diagram showing a circuit configuration of a camera and an interchangeable lens embodying the present invention. In FIG. 1, reference numeral 1 denotes a camera as an imaging apparatus, and 2 denotes an interchangeable lens. The camera 1 has a mount portion 3, and the interchangeable lens 2 has a lens mount portion 4. Inside the camera 1, there are a battery 11, a power generation unit 12, and a camera-side microcomputer 13. The power generation unit 12 receives the voltage output from the battery 11, generates a power supply voltage that is optimally stabilized so that the electric circuit such as the camera-side microcomputer 13 operates, and supplies this to each part of the electric circuit. . Reference numeral 19 denotes an image pickup circuit for taking a digital image, which includes an image pickup element, its drive circuit, an AD conversion circuit, an image processing circuit and the like. The imaging circuit 19 operates based on the VD signal output from the camera-side microcomputer 13, a serial control signal (not shown), and other timing signals. The operation of the imaging circuit will be described with reference to FIG. 2 which is a timing chart schematically showing the operation of the imaging circuit. First, the camera-side microcomputer 13 notifies the imaging circuit 19 of an imaging operation start command by serial communication. The imaging circuit 19 that has received the imaging operation start command switches the operation mode at the timing when the VD signal is input thereafter. When the imaging circuit 19 detects the first VD signal, the imaging circuit 19 cancels the standby state. Next, when the second VD signal is detected, the charge remaining in the photodiode (FD) of the image sensor is reset, and the accumulation operation is started. Subsequently, when the third VD signal is detected, the accumulation operation is terminated, and an operation for reading out the electric charge accumulated in the FD is started. When the fourth VD signal is detected, the reading operation is completed, and the imaging operation is completed.

  Also, the normal camera 1 has a photometric sensor for exposure control, a distance measuring sensor for autofocus control, a liquid crystal monitor and its drive circuit, a memory for recording digital images, a motor driver for mechanical drive, etc. However, it is not shown because it is not deeply related to the gist of the present invention.

  Reference numerals 14 to 18 denote contact portions for exchanging electrical signals with the interchangeable lens 2 provided on the camera 1 side, and reference numeral 14 denotes a camera side for supplying the lens power generated by the power generation unit 12 to the interchangeable lens 2. Power supply terminal. Reference numeral 15 denotes a camera-side CLK terminal as a first terminal for transmitting a synchronous clock signal or the like when the camera 1 and the interchangeable lens 2 communicate with each other. Reference numeral 16 denotes a camera-side DOC terminal as a second terminal for transmitting communication data from the camera 1 to the interchangeable lens 2, and reference numeral 17 denotes a camera-side DOL terminal for receiving communication data from the interchangeable lens 2 to the camera 1. . These terminals 15 to 17 are connected to the camera-side microcomputer 13. Reference numeral 18 denotes a camera-side ground terminal.

  Inside the interchangeable lens 2 is a lens-side microcomputer 21. Reference numerals 24 to 28 denote contact portions for exchanging electrical signals with the camera 1 provided on the lens 2 side. Reference numeral 24 denotes a lens-side power supply terminal for receiving power supply from the camera 1. Reference numeral 25 denotes a lens side CLK terminal as a first lens side terminal for transmitting a synchronous clock signal or the like when communicating with the camera 1. Reference numeral 26 denotes a lens side DOC terminal as a second lens side terminal for receiving communication data from the camera 1 to the interchangeable lens 2, and reference numeral 27 denotes a lens side DOL terminal for transmitting communication data from the interchangeable lens 2 to the camera 1. It is. Reference numeral 28 denotes a lens side ground terminal.

  When the interchangeable lens 2 is normally attached to the camera 1, the camera side terminals 14 to 18 and the lens side terminals 24 to 28 are connected one-to-one as illustrated.

  A diaphragm 22 adjusts the amount of light incident from the optical lens 23. Reference numeral 29 denotes a drive control circuit for driving the diaphragm 22 and the optical lens 23 as optical members. The drive control circuit 29 can be controlled by an IRIS_CTRL signal output from the lens-side microcomputer 21 and can be controlled by a signal (LENS_CTL_C signal) from the CLK terminal. Note that the drive control circuit 29 is controlled by the lens-side microcomputer 21 so that a signal (LENS_CTL_C signal) from the CLK terminal is invalid during synchronous communication.

  The present invention can also be applied when wireless communication is performed between the camera and the lens.

  In this embodiment, the camera-side terminals 14 to 18 are provided in the mount unit 3. However, the camera-side CLK terminal 15 may be provided in a place other than the mount unit 3. Similarly, although the lens side terminals 24 to 28 are provided in the lens mount unit 4, the lens side CLK terminal 25 may be provided in a place other than the lens mount unit 4.

  FIG. 3 shows a configuration related to serial communication control among circuit configurations built in the camera side microcomputer 13 or the lens side microcomputer 21. The camera-side microcomputer 13 and the lens-side microcomputer 21 are of course different from each other, but the configuration related to serial communication control may have the same configuration requirements, and will be described with reference to a common drawing.

For example, a crystal oscillator or a ceramic vibrator is often used as an oscillator 31. Such an oscillator is not limited to being built in a microcomputer but may be externally attached. Reference numeral 32 denotes a clock generator circuit which is connected to the oscillator 31 to generate a source clock, a multiplier circuit for converting the source clock to a higher frequency, and a high frequency clock converted by the multiplier circuit. It consists of a clock generation circuit that generates clocks of various frequencies by performing rounding and synthesis. A communication control circuit 33 will be described in detail with reference to FIG. Reference numeral 34 can count the number of pulses of the signal input by the counter / timer circuit or measure the time width of the input signal. The clock signal generated by the clock generation circuit 32 is supplied to the communication control circuit 33 and the counter / timer circuit 34. Reference numerals 35 to 37 denote IO control circuits which switch data input / output directions, input / output signal types, and input / output circuit forms of the input / output terminals 45 to 47, respectively. Data input / output direction switching is literally switching between using a terminal as a data input or data output. The input / output signal type switching is switching between connecting an input / output signal of a normal parallel IO signal to a terminal or connecting an input / output signal to / from the communication control circuit 33 to a terminal. The switching of the input / output circuit form is performed by switching between the output using the open drain method or the CMOS method described in Patent Document 1 described above and switching whether or not the pull-up resistor is connected. The IO control circuit 35 performs input / output switching of the input / output terminal 45, and a synchronous clock signal SCLK is connected from the communication control circuit 33, and this SCLK signal can be supplied to the counter / timer circuit 34. The IO control circuit 36 performs input / output switching of the input / output terminal 46, and a serial communication data output signal TXD is connected from the communication control circuit 33. The IO control circuit 37 performs input / output switching of the input / output terminal 47, and a serial communication data input signal RXD is connected from the communication control circuit 33.
An interrupt control circuit 38 is connected to interrupt generation signals from the communication control circuit 33 and the counter / timer circuit 34. Reference numeral 40 denotes a data bus in the microcomputer. The communication control circuit 33, the counter / timer circuit 34, and the IO control circuits 35 to 37 are connected to the data bus 40 and can exchange data necessary for the operation. In the microcomputer, there are other circuit configurations such as an ALU, a program counter, a ROM, a RAM, and an AD converter other than those shown in the figure, but they are not shown.

  In the case of the camera side microcomputer 13, the input / output terminal 45 is connected to the camera side CLK terminal 15 of FIG. 1, the input / output terminal 46 is connected to the camera side DOC terminal 16 of FIG. 1, and the input / output terminal 47 is connected to the camera side DOL terminal of FIG. 17 respectively.

  In the case of the lens side microcomputer 21, the input / output terminal 45 is connected to the lens side CLK terminal 25 of FIG. 1, the input / output terminal 46 is connected to the lens side DOL terminal 27 of FIG. 1, and the input / output terminal 47 is connected to the lens side DOC terminal of FIG. 26, respectively. This is because in the description of the present embodiment, the DOC signal is transmission data from the camera to the lens, and the DOL signal is transmission data from the lens to the camera.

  FIG. 4 is a diagram for explaining a more detailed configuration of the communication control circuit 33 shown in FIG. Clock signals of various frequencies generated by the clock generation circuit 32 are input to the baud rate generator 51. The baud rate generator 51 generates a clock signal necessary for communication control according to various communication setting data sent through the data bus 40. The communication setting data includes switching between communication master and slave, switching between synchronous communication and asynchronous communication, synchronous clock frequency setting for synchronous communication, asynchronous sampling clock frequency setting for asynchronous communication, and the like. When the synchronous communication and the communication master are set by the communication setting data, the synchronous clock signal SCLK according to the synchronous clock frequency setting value in the case of synchronous communication is output. When the synchronous communication and the communication slave are set by the communication setting data, the synchronous clock signal SCLK is input. The synchronous clock signal SCLK is also supplied to 52 transmission / reception control blocks. When asynchronous communication is set by the communication setting data, a sampling clock according to the asynchronous sampling clock frequency setting in the case of asynchronous communication is supplied to the transmission / reception control block 52. The transmission / reception control block 52 also supplies a shift clock to a transmission shift register 53 and a reception shift register 54, which will be described later, according to various communication setting data transmitted through the data bus 40, and inputs / outputs a transmission / reception trigger signal for serial communication. Perform timing control. An interrupt signal is also generated at the completion timing of serial communication transmission / reception.

  Reference numeral 53 denotes a transmission shift buffer which inputs data to be transmitted by serial communication in parallel and serially outputs it as a signal TXD. A shift clock for serial output is supplied from the transmission / reception control block 52. When performing asynchronous communication, a transmission trigger signal is input from the transmission / reception control block 52. A reception shift register 54 serially inputs a data signal RXD received by serial communication and outputs it in parallel. A shift clock for serial input is supplied from the transmission / reception control block 52. When performing asynchronous communication, a reception trigger signal is output to the transmission / reception control block 52. A transmission data register 55 receives transmission data from the data bus 40 and sets data in the transmission shift register 53. Reference numeral 56 denotes a reception data register which receives reception data from the reception shift register 54 and can output it to the data bus 40.

  As described in the background art, FIG. 6 is a protocol example between the camera and the interchangeable lens in the synchronous communication system. The signal CLK is a synchronous clock for synchronous communication. Since the camera side is normally the communication master side between the camera and the interchangeable lens, the camera outputs and the lens inputs. In this example, the data of the signals DOC and DOL change in synchronization with the falling edge of the synchronous clock CLK with 8 bits as one transmission unit. At the rising edge of the synchronous clock CLK, the camera 1 side converts the DOL data into the lens. The second side is described as an example of latching DOC data. How the levels of the signals DOC and DOL change in synchronization with the falling edge of the synchronous clock CLK depends on the value of each bit of data to be transmitted.

  A control flow when the camera-side microcomputer communicates with the interchangeable lens according to the communication protocol shown in FIG. 6 will be described with reference to FIG.

  (301) The input level of the terminal that outputs the synchronous clock signal CLK is checked to determine whether or not the lens side is in the Busy state. In this example, the state in which the lens side has this terminal at the L level is the Busy state, and in this state, the camera cannot communicate with the lens. When the input level of the terminal that outputs the signal CLK is H level and the lens side is not in the Busy state, the process proceeds to (302).

  (302) First, data DATA_C1 to be transmitted to the lens is set in the serial data transmission shift register, and serial communication in one transmission unit is performed. Normally, data DATA_C1 transmitted to the lens is a certain command to the lens, and response data from the lens responding thereto is data DATA_L2 at the time of communication of the next one transmission unit. Therefore, since the data DATA_L1 sent from the lens to the camera at this time is don't care data, it is not particularly read and treated.

  (303) The input level of the terminal that outputs the synchronous clock signal CLK is checked to determine whether or not the lens side is in the busy state. While the lens side analyzes the content of the transmitted data DATA_C1 and performs the corresponding processing, the lens 2 outputs the CLK signal to the Bus level and enters the Busy state. The process proceeds to (304) after waiting for the processing to be completed and the lens side not to be in the Busy state.

  (304) Next, data DATA_C2 to be transmitted to the lens is set in the serial data transmission shift register, and serial communication in one transmission unit is performed. When the data DATA_C1 transmitted in (302) is a command for transmitting lens-specific information to the camera to the lens, the content of the data DATA_C2 becomes don't care data, and the data DATA_L2 sent back from the lens Will be meaningful.

  (305) The received data DATA_L2 is taken into the reception shift register.

  Next, a control flow when the lens-side microcomputer communicates with the camera according to the communication protocol shown in FIG. 6 will be described with reference to FIG. The lens side microcomputer becomes a slave side for communication. Therefore, the reception of serial communication in one transmission unit from the camera is detected by a communication interrupt function that generates an interrupt signal when the number of falling edges of the synchronous clock signal CLK is counted a predetermined number.

  (401) First, the terminal that receives the synchronous clock signal CLK is set to L level so that the camera can determine that the lens side is in the Busy state.

  (402) The transmission data DATA_C1 from the camera 1 input to the reception shift register is input, and the contents thereof are analyzed. Note that the transmission data from the camera is initially DATA_C1, but since DATA_C2 or the like may be sent after that, it is described as DATA_Cx in the flowchart.

  (403) When the content of the transmission data DATA_C1 from the camera 1 is a lens-side actuator drive command, the process proceeds to (404).

  (404) The actuator on the lens side is driven according to the content of the transmission data DATA_C1 from the camera.

  (405) It is determined whether or not the processing related to the driving of the actuator on the lens side is completed and communication from the next camera can be received. If reception is possible, the process proceeds to (407).

  If it is determined in step (403) that the transmission data DATA_C1 from the camera is a lens-specific data transmission request, the process proceeds to (406).

  (406) The lens-specific data requested according to the transmission data DATA_C1 from the camera is set in the transmission shift register.

  (407) The terminal that receives the synchronous clock signal CLK is set to H level so that the camera can determine that the lens side is no longer in the Busy state.

  This completes the description of the basic control flow of the camera-side microcomputer and lens-side microcomputer in synchronous communication. In a camera capable of switching between synchronous communication and asynchronous communication as in this embodiment, after confirming that both the camera and the interchangeable lens are compatible with the asynchronous system, the communication is performed after switching to the asynchronous system.

  By the way, if the communication method is switched to asynchronous communication, it is possible to improve the waiting time by the Busy confirmation at the time of synchronous communication, but there is a possibility that flickering occurs due to a communication time lag. This will be described in detail below.

  In general, a camera that automatically performs exposure control automatically adjusts parameters such as a shutter speed and an aperture opening when ambient brightness changes so that a captured image always has an optimal exposure. Therefore, in moving image recording, the parameter change and the operation timing of the imaging circuit must be synchronized. This is because if a parameter is changed while an image of a certain frame is being imaged, underexposure or overexposure occurs in the same frame, and thus flickering occurs on the display. FIG. 13 is a timing chart schematically illustrating the operation of the image pickup circuit during moving image recording. The imaging circuit receives a serial communication command from the camera side microcomputer and performs a predetermined setting. Thereafter, each operation mode is switched based on a timing signal (VD signal) input from the camera-side microcomputer. Conventionally, in order to prevent flickering, the parameter is changed during a period in which the imaging circuit does not perform an exposure operation (from accumulation completion & reading start to FD reset & accumulation start). However, since the aperture drive of the interchangeable lens is performed via communication, there is a time lag from when the camera transmits an aperture drive command to when the aperture is actually driven, and flicker cannot be eliminated. FIG. 14 is a timing chart of a communication protocol and timing signal at the time of moving image recording in the related art relating to lens driving of an aperture and focus in asynchronous communication between a camera and an interchangeable lens. In the asynchronous system, the clock signal for synchronization is not used, and is fixed at the H level. When performing aperture driving, the camera transmits DATA_C1 as a command for notifying the aperture value to the interchangeable lens using the data signal DOC. The interchangeable lens analyzes the command content of the received DATA_C1. Based on the result of the analysis, reply information DATA_L1 is returned to the camera using the data signal DOL. When the camera receives the reply information, the camera transmits an aperture drive command DATA_C2 to the interchangeable lens. When the interchangeable lens receives the sent command DATA_C2, it analyzes the contents. As a result of the analysis, if it is determined that the command is aperture drive, the lens controls the LENS_CTL_L signal to drive the aperture drive circuit, and controls the aperture aperture diameter notified by the previously received command DATA_C1. At the same time, reply information DATA_L2 to the command DATA_C2 is returned to the camera. In this way, there is a time lag between the command transmission time and the command analysis time from when the camera transmits the aperture drive command to when the aperture drive operation is actually started. If this time lag becomes longer than the period when the imaging operation is not performed as shown in FIG. 14, flickering occurs.

  Also, in a camera that automatically performs focus control, it is preferable to perform focus drive during a period in which the imaging circuit does not perform an exposure operation. However, focus drive is performed during the exposure operation because of a communication time lag, similar to the aperture drive. There is a fear.

  Here, in a camera capable of switching between synchronous communication and asynchronous communication as in this embodiment, the CLK terminal that outputs a synchronous clock signal during synchronous communication is unused during asynchronous communication. By using a CLK terminal that is unused during asynchronous communication, a signal for notifying the start of driving of the aperture is output, so that the aperture drive and focus drive of the interchangeable lens can be performed without causing a communication time lag during asynchronous communication. it can. The detailed method will be described below.

  FIG. 5 is a flowchart relating to aperture driving in asynchronous communication of the camera system comprising the camera 1 and the interchangeable lens 2 embodying the present invention. The operation of each of the camera side and interchangeable lens side microcomputers will be described later. First, this figure will be described as the overall operation flow.

  When a power switch (not shown) is turned on and the camera 1 and the interchangeable lens 2 become operable, the operation starts from (101) in the flowchart.

  (101) The camera 1 and the interchangeable lens 2 communicate by synchronous communication as an initial setting of the communication method. FIG. 6 is a protocol example of the synchronous communication system. In this embodiment, it is assumed that the camera 1 is a clock master and outputs a CLK signal. The camera 1 and the lens 2 respectively output and input data in accordance with the output timing of the CLK signal. The DOC signal is an output signal from the camera 1 to the lens 2, and commands DATA_C1 and DATA_C2 are transmitted. The DOL signal is an output signal from the lens 2 to the camera 1, and DATA_L 1 and DATA_L 2 are replies to commands from the camera 1. Between each command communication, a Busy signal indicating that the slave side, that is, the lens 2 is processing is output.

  (102) During the synchronous communication, the lens 2 controls the drive control circuit 29 so that the aperture driving by the signal (LENS_CTL_C signal) from the CLK terminal is invalidated.

  (103) Then, after confirming that both the camera 1 and the interchangeable lens 2 are compatible with the asynchronous system, the communication is performed after switching to the asynchronous system. In the present embodiment, description of switching from the synchronous method to the asynchronous method is omitted.

  (104) The lens 2 controls the drive control circuit 29 so that the aperture driving by the signal (LENS_CTL_C signal) from the CLK terminal becomes effective.

  (105) Asynchronous communication is performed between the camera 1 and the interchangeable lens 2. FIG. 7 shows an example of an asynchronous protocol. In the asynchronous system, the CLK signal is not used for communication. For this reason, the camera 1 controls the CLK signal terminal to be fixed at the H level output. Further, the interchangeable lens 2 sets the CLK signal terminal as an input and enables the L edge interrupt. The DOC signal and the DOL signal, which are communication signals in the asynchronous system, are transmitted with a start bit added at the beginning and a stop bit added at the end of the communication data. Unlike the synchronous method, the asynchronous method does not set Busy.

  FIG. 8 is a timing chart for explaining the aperture driving operation during moving image recording. Before performing the aperture driving operation, the camera 1 transmits a parameter for determining the aperture aperture value to the interchangeable lens 2 as a command DATA_C1 using the data signal line DOC. In FIG. 8, the command is transmitted immediately before the aperture driving operation, but for convenience of explanation, any timing before the aperture driving operation may be used. When the lens 2 receives the command DATA_C1, the lens 2 analyzes the content. If the aperture value parameter is determined as a result of the analysis, reply information is returned to the camera 1 using the data signal line DOL.

  (106) Upon receiving the return information from the lens 2, the camera 1 outputs an L pulse to the CLK signal terminal to drive the diaphragm 22 (107).

  (108) When the LENS_CTL_C signal (CLK signal) output from the camera 1 is input, the drive control circuit 29 drives the aperture 22 so that the aperture diameter value notified by the DATA_C1 received earlier is obtained.

  This is the end of the description of the operation flow related to the aperture driving of the camera system including the camera 1 and the interchangeable lens 2.

  Next, an operation flow related to aperture driving in asynchronous communication with the interchangeable lens 2 in the camera side microcomputer 13 will be described with reference to a flowchart shown in FIG.

  When a power switch (not shown) is turned on and the camera-side microcomputer 13 starts operating and communicates with the interchangeable lens 2, the operation flow is executed from (111) in FIG.

  (111) As described in the operation flow (101) of the camera system in FIG. 4, first, the communication control circuit 33 and the IO control circuits 35 to 37 are set so as to perform communication in a synchronous manner. Thereafter, after confirming that both the camera-side microcomputer 13 and the lens-side microcomputer 21 support asynchronous communication, the setting is switched to the asynchronous method.

  (112) The communication control circuit 33 and the IO control circuits 35 to 37 are set so as to perform asynchronous communication. The camera-side microcomputer 13 controls the IO control circuit 35, which is a CLK signal terminal not used in the asynchronous communication system, to be fixed at the H level output.

  (113) Communication is performed in an asynchronous manner. Data DATA_C1 to be transmitted to the interchangeable lens is set in the transmission shift register 53, and a command is transmitted to the interchangeable lens 2 from the IO control circuit 36 which is a TXD signal terminal. The camera-side microcomputer 13 transmits a parameter DATA_C1 for determining the aperture diameter value to the interchangeable lens 2.

  (114) The reply data from the interchangeable lens 2 is input to the IO control circuit 37 connected to the RXD terminal.

  (115) Here, if the exposure condition changes due to the subject brightness change or the like and the camera side microcomputer 13 determines that the aperture drive is necessary, the process proceeds to (116).

  (116) An aperture driving signal is output. The camera-side microcomputer 13 controls to output an L pulse signal to the IO control circuit 35 in accordance with the timing of the VD signal at which the imaging circuit 19 is set to standby.

  The timing for outputting the L pulse signal is preferably matched with the timing of the VD signal at which the imaging circuit 19 is set to standby, but is not limited to this. The timing of outputting the L pulse signal may be controlled so that the driving operation of the diaphragm can be completed before the VD signal for resetting the charge remaining in the FD and starting the accumulation operation is output.

  Next, an operation flow related to aperture driving in asynchronous communication with the camera in the lens-side microcomputer 21 will be described with reference to a flowchart shown in FIG.

  When the interchangeable lens 2 is attached to the camera 1 and the lens-side microcomputer 21 becomes operable upon receiving power supply from the camera 1, the operation flow is executed from (131) in FIG.

  (131) As described in the operation flow (101) of the camera system in FIG. 4, first, the communication control circuit 33 and the IO control circuits 35 to 37 are set so as to perform communication in a synchronous manner.

  (132) Further, the lens side microcomputer 21 performs setting for invalidating the control function by the LENS_CTL_C signal (CLK signal) which is an input signal to the drive control circuit 29.

  (133) Then, after confirming that both the camera-side microcomputer 13 and the lens-side microcomputer 21 are compatible with the asynchronous communication system, the setting is switched to the asynchronous system. The communication control circuit 33 and the IO control circuits 35 to 37 are set so as to perform asynchronous communication. The lens-side microcomputer 21 sets the IO control circuit 35 connected to the CLK signal terminal not used in the asynchronous communication method as an input.

  (134) Setting for enabling the control function by the input signal LENS_CTL_C signal to the drive control circuit 29 is performed. With this setting, when an L pulse is input to the LENS_CTL_C signal, the diaphragm driving circuit drives the diaphragm 22 to a predetermined diaphragm opening diameter value.

  (135) Perform asynchronous communication. The lens-side microcomputer 21 analyzes the received command DATA_C1 from the camera 1 input to the IO control circuit 37, and transmits reply information DATA_L1 to the camera 1 using the IO control circuit 36 based on the analysis result. If DATA_C1 is the aperture aperture diameter value parameter as a result of the analysis, the lens side microcomputer 21 notifies a predetermined signal via the IRIS_CTRL line, and the aperture opening notified from the camera 1 when the drive control circuit 29 performs the aperture operation. Set the aperture to be the same.

(136) When an L pulse signal is input from the camera to the IO control circuit 35,
(137) The drive control circuit 29 drives the diaphragm 21. At this time, the aperture diameter is controlled to be an aperture value based on DATA_C1 received in advance by communication.

  In this embodiment, the driving of the stop has been described. However, the optical member is not limited to the stop but may be a focus lens.

  In this embodiment, the signal level of LENS_CTL_L is fixed to the H level as shown in FIG. 8, but the LENS_CTL_L line may not be provided. Further, the IRIS_CTRL line and the LENS_CTL_L line may be the same by changing the configuration of the drive control circuit 29.

  In addition, the LENS_CTL_C signal output from the CLK terminal may be input to the drive control circuit 29 via the lens-side microcomputer 21. In this case, the LENS_CTL_C line is not necessary.

(Example 2)
In the first embodiment, a configuration is used in which a signal for notifying the start of driving of the diaphragm is output using a CLK terminal that is unused during asynchronous communication. Since there is no need to switch the connection of each terminal during synchronous communication and asynchronous communication, Example 1 is the most preferred embodiment, but the terminal that outputs the signal is not limited to the CLK terminal, It may be a terminal.

  For example, during asynchronous communication, a signal notifying the start of driving of the aperture 22 may be output from the DOC terminal, and data such as an aperture aperture value parameter may be sent from the camera 1 to the lens 2 using the CLK terminal. In this case, during asynchronous communication, it is necessary to switch the circuit so that the IO control circuit 35 is connected to the transmission shift register 53 on the camera side and the IO control circuit 35 is connected to the reception shift register 54 on the lens side. In this example, the LENS_CTL_C line is configured to connect the lens side DOC terminal 26 and the drive control circuit 29. The lens side microcomputer 21 disables the control function based on the signal (LENS_CTL_C signal) input from the DOC terminal during synchronous communication, and enables the control function during asynchronous communication.

DESCRIPTION OF SYMBOLS 1 Camera 2 Interchangeable lens 13 Camera side microcomputer 15 Camera side CLK terminal 16 Camera side DOC terminal 17 Camera side DOL terminal 19 Imaging circuit 21 Lens side microcomputer 22 Aperture 23 Optical lens 25 Lens side CLK terminal 26 Lens side DOC terminal 27 Lens Side DOL terminal 29 Drive control circuit 32 Clock generation circuit 33 Communication control circuit

Claims (18)

A an interchangeable lens mounted on the imaging device,
An optical member;
A first lens terminal and a second lens terminal for communicating with the imaging device;
Drive control means for controlling the drive of the optical member;
A first communication mode in which data communication is performed at the second lens terminal in synchronization with a clock signal received from the imaging device via the first lens terminal, and a signal received from the imaging device without being synchronized. A second control mode capable of switching a second communication mode for data communication with the second lens terminal, and a lens control means for controlling communication with the imaging device,
The lens control unit performs the image pickup device and the data communication in the first communication mode, after that the interchangeable lens corresponding to said second communication mode is determined in the imaging apparatus, the second Switch to the communication mode of
The lens control means receives data relating to the driving amount of the optical member from the imaging device via the second lens terminal in the second communication mode, and based on the received data relating to driving of the optical member. Te, the interchangeable lens the driving control means is characterized by control to Rukoto to start driving of the optical member in accordance with a predetermined pulse signal received from the imaging device via the first lens terminal. In the second communication mode, the lens control means, when receiving the data about the driving amount of the second lens terminal through the optical member, a control signal indicating the drive amount to the drive control means The interchangeable lens according to claim 1, wherein the interchangeable lens is output. In the second communication mode, the drive control unit receives the control signal from the lens control unit, and then receives the predetermined pulse signal from the imaging device based on the received control signal. the interchangeable lens according to claim 2, characterized in that to start driving of the optical member. 2. The lens control unit according to claim 1, wherein the predetermined pulse signal is set to be valid in the second communication mode, and the predetermined pulse signal is set to be invalid in the first mode. 4. The imaging device according to any one of items 1 to 3. A an interchangeable lens mounted on the imaging device,
An optical member;
A first lens terminal and a second lens terminal for communicating with the imaging device;
Drive control means for controlling the drive of the optical member;
A first communication mode in which data communication is performed at the second lens terminal in synchronization with a clock signal received from the imaging device via the first lens terminal, and a signal received from the imaging device without being synchronized. A second control mode capable of switching a second communication mode for data communication with the first lens terminal, and a lens control means for controlling communication with the imaging device;
The lens control unit performs the image pickup device and the data communication in the first communication mode, after that the interchangeable lens corresponding to said second communication mode is determined in the imaging apparatus, the second Switch to the communication mode of
The lens control means receives data relating to the driving amount of the optical member from the imaging device via the first lens terminal in the second communication mode, and based on the received data relating to driving of the optical member. Te, the interchangeable lens the driving control means is characterized by control to Rukoto to start driving of the optical member in accordance with a predetermined pulse signal received from the imaging device via the second lens terminal. In the second communication mode, the lens control means, when receiving the data about the driving amount of the first lens terminal through the optical member, a control signal indicating the drive amount to the drive control means The interchangeable lens according to claim 5, wherein the interchangeable lens is output. In the second communication mode, the drive control unit receives the control signal from the lens control unit, and then receives the predetermined pulse signal from the imaging device based on the received control signal. the interchangeable lens according to claim 6, characterized in that to start driving of the optical member. The lens control means sets the predetermined pulse signal valid in the second communication mode, and sets the predetermined pulse signal invalid in the first mode. The interchangeable lens of any one of thru | or 7.   The interchangeable lens according to claim 1, wherein the optical member is a diaphragm or a focus lens. The interchangeable lens has a lens mount portion,
The interchangeable lens according to any one of claims 1 to 9, wherein the second lens terminal is installed in the lens mount portion. An imaging device capable of mounting an interchangeable lens comprising an optical member and a drive control means for controlling the driving of the optical member,
A first terminal and a second terminal for communicating with the interchangeable lens;
A first communication mode in which data communication is performed at the second terminal in synchronization with a clock signal transmitted to the interchangeable lens via the first terminal, and the first communication mode without being synchronized with a signal transmitted to the interchangeable lens. A second communication mode for data communication at the terminal 2 and a control means for controlling communication with the interchangeable lens,
Wherein said control means performs said interchangeable lens and data communication in a first communication mode, switch to the second communication mode after the interchangeable lens is determined to be corresponding to the second communication mode,
In the second communication mode, the control means transmits data relating to the driving amount of the optical member to the interchangeable lens via the second terminal, and then performs the driving control via the first terminal. imaging apparatus characterized that you send a predetermined pulse signal indicating the start of driving of the optical member unit in the interchangeable lens. An imaging device capable of mounting an interchangeable lens comprising an optical member and a drive control means for controlling the driving of the optical member,
A first terminal and a second terminal for communicating with the interchangeable lens;
A first communication mode in which data communication is performed at the second terminal in synchronization with a clock signal transmitted to the interchangeable lens via the first terminal, and the first communication mode without being synchronized with a signal transmitted to the interchangeable lens. A second communication mode for data communication at one terminal, and a control means for controlling communication with the interchangeable lens,
Wherein said control means performs said interchangeable lens and data communication in a first communication mode, switch to the second communication mode after the interchangeable lens is determined to be corresponding to the second communication mode,
In the second communication mode, the control means transmits data relating to the drive amount of the optical member to the interchangeable lens via the first terminal, and then performs the drive control via the second terminal. imaging apparatus characterized that you send a predetermined pulse signal indicating the start of driving of the optical member unit in the interchangeable lens. The optical member, the imaging apparatus according to claim 11 or 12, characterized in that an aperture or a focus lens. The imaging apparatus has a mount part,
It said second terminal, the image pickup apparatus according to any one of claims 11 to 13, characterized in that it is installed in the mounting portion. A method of controlling an interchangeable lens that can be attached to an imaging device and includes an optical member, and a first lens terminal and a second lens terminal for communicating with the imaging device,
Controlling the driving of the optical member;
Controlling communication with the imaging device,
A first communication mode in which data communication is performed at the second lens terminal in synchronization with a clock signal received from the imaging device via the first lens terminal, and a signal received from the imaging device without being synchronized. The second communication mode for data communication with the second lens terminal can be switched,
Performs the image pickup device and the data communication in the first communication mode, after that the interchangeable lens corresponding to said second communication mode is determined in the imaging apparatus switches to the second communication mode,
In the second communication mode, data relating to the driving amount of the optical member is received from the imaging device via the second lens terminal, and the first data is received based on the received data relating to driving of the optical member . control to control method of the interchangeable lens, characterized in Rukoto to start the drive of the optical member in accordance with a predetermined pulse signal received from the imaging device via the lens terminal. A method of controlling an interchangeable lens that can be attached to an imaging device and includes an optical member, and a first lens terminal and a second lens terminal for communicating with the imaging device,
Controlling the driving of the optical member;
Controlling communication with the imaging device,
A first communication mode in which data communication is performed at the second lens terminal in synchronization with a clock signal received from the imaging device via the first lens terminal, and a signal received from the imaging device without being synchronized. The second communication mode for data communication with the first lens terminal can be switched,
Performs the image pickup device and the data communication in the first communication mode, after that the interchangeable lens corresponding to said second communication mode is determined in the imaging apparatus switches to the second communication mode,
In the second communication mode, data relating to the driving amount of the optical member is received from the imaging device via the first lens terminal , and the second data is received based on the received data relating to driving of the optical member . control to control method of the interchangeable lens, characterized in Rukoto to start the drive of the optical member in accordance with a predetermined pulse signal received from the imaging device via the lens terminal. An imaging device having a first terminal and a second terminal for communicating with the interchangeable lens, to which an interchangeable lens including an optical member and a drive control means for controlling driving of the optical member can be mounted. Because
Controlling communication with the interchangeable lens,
A first communication mode in which data communication is performed at the second terminal in synchronization with a clock signal transmitted to the interchangeable lens via the first terminal, and the first communication mode without being synchronized with a signal transmitted to the interchangeable lens. The second communication mode for data communication at the terminal 2 can be switched,
It said first performs the interchangeable lens data communication in a communication mode, switch to the second communication mode after the interchangeable lens is determined to be corresponding to the second communication mode,
In the second communication mode, after data related to the driving amount of the optical member is transmitted to the interchangeable lens via the second terminal, the optical member is transmitted to the drive control means via the first terminal. control method for an imaging apparatus a predetermined pulse signal indicating the start of driving of which is characterized that you send to the interchangeable lens. An imaging device having a first terminal and a second terminal for communicating with the interchangeable lens, to which an interchangeable lens including an optical member and a drive control means for controlling driving of the optical member can be mounted. Because
Controlling communication with the interchangeable lens,
A first communication mode in which data communication is performed at the second terminal in synchronization with a clock signal transmitted to the interchangeable lens via the first terminal, and the first communication mode without being synchronized with a signal transmitted to the interchangeable lens. The second communication mode for data communication at the terminal 1 can be switched,
It said first performs the interchangeable lens data communication in a communication mode, switch to the second communication mode after the interchangeable lens is determined to be corresponding to the second communication mode,
In the second communication mode, after data related to the driving amount of the optical member is transmitted to the interchangeable lens via the first terminal, the optical member is transmitted to the drive control means via the second terminal. control method for an imaging apparatus a predetermined pulse signal indicating the start of driving of which is characterized that you send to the interchangeable lens.

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