JP2019133195A - interchangeable lens - Google Patents

Abstract

To provide an interchangeable lens allowing to confirm whether an interchangeable lens is operating in accordance with what drive instruction currently.SOLUTION: An interchangeable lens includes: a driven member for changing its state in response to reception of driving force; drive instruction receiving means for sequentially receiving a drive instruction signal representing a drive instruction to the driven member from a camera body; first drive control means for performing first drive control of the driven member on the basis of the drive instruction signal received by the drive instruction receiving means; confirmation request receiving means for receiving a state confirmation signal representing a confirmation request for a drive control state of the first drive control means from the camera body; and drive state transmitting means for transmitting a drive state signal representing the drive control state of the first drive control means to the camera body in response to reception of the state confirmation signal by the confirmation request receiving means. The drive instruction signal includes a unique identifier for each drive instruction signal. The drive state transmitting means transmits a drive state signal including an identifier included in the drive instruction signal received by the drive instruction receiving means.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an interchangeable lens.

  Conventionally, an interchangeable lens that receives an instruction to drive a driven member such as a focus lens from a camera body is known. For example, Patent Document 1 describes an interchangeable lens that, when a lens drive command is transmitted from a camera body, drives the lens to a specified position and transmits a lens drive result to the camera body.

JP 2000-75385 A

  The prior art has a problem that it is impossible for the camera body to know which drive instruction the interchangeable lens that has received a plurality of drive instructions from the camera body in time series is currently operating.

  An interchangeable lens according to a first aspect of the present invention is an interchangeable lens that is detachably attached to a camera body, and includes a drive unit that drives the lens by a driving force, and a plurality of drive instruction signals that indicate a drive instruction to the drive unit And a reception unit that sequentially receives from the camera body a plurality of confirmation signals indicating confirmation requests for confirming the execution state of the drive instruction, and drive control of the drive unit is performed by the drive instruction signal received by the reception unit. A control unit that performs transmission, and a transmission unit that transmits a state signal indicating an execution state of the corresponding driving instruction to the camera body upon reception of the confirmation signal, and the plurality of driving instruction signals are each of the driving instructions An identifier for identifying a signal is included, and the status signal includes the identifier included in the corresponding drive instruction signal.

  According to the present invention, it is possible to realize a camera system that allows the camera body to check which drive instruction from the camera body is currently operating according to which drive instruction.

It is a figure which shows the external appearance of the camera system which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the structure of the camera system 1 which concerns on 1st Embodiment. 2 is a block diagram illustrating details of a transmission path between a camera body 100 and an interchangeable lens 200. FIG. It is a wave form diagram showing command data communication. It is a wave form diagram showing hot line communication. It is a figure which shows the positional relationship of the zoom lens 210b and the focus lens 210c. It is a time chart of an automatic focus adjustment process. 5 is a flowchart of automatic focus adjustment processing executed by a body control unit 103 and a lens control unit 203. It is a time chart of an automatic focus adjustment process.

(First embodiment)
Hereinafter, an interchangeable lens type digital camera according to a first embodiment of the present invention will be described. In the following description, portions particularly related to the present invention will be described, and illustration and description of other portions will be omitted.

  FIG. 1A is a perspective view showing an interchangeable lens type camera system to which the present invention is applied. FIG. 1 (a) shows only the devices and apparatuses according to the present invention, and illustration and description of the other devices and apparatuses are omitted. The camera system 1 includes a camera body 100 and an interchangeable lens 200 that can be attached to and detached from the camera body 100.

  The camera body 100 is provided with a body side mount 101 to which the interchangeable lens 200 is detachably attached. At a position near the body-side mount portion 101 (inner peripheral side of the body-side mount portion 101), a holding portion (electrically holding the contact point in a state of partially protruding toward the inner peripheral side of the body-side mount portion 101) ) 102 is provided. The holding portion 102 is provided with a plurality of contacts.

  In addition, the interchangeable lens 200 is provided with a lens side mount portion 201 corresponding to the body side mount portion 101 to which the camera body 100 is detachably attached. In the vicinity of the lens side mount part 201 (inner peripheral side of the lens side mount part 201), a holding part (electrical) that holds the contact in a state of partially protruding to the inner peripheral side of the lens side mount part 201 ) 202 is provided. The holding portion 202 is provided with a plurality of contacts.

  When the interchangeable lens 200 is attached to the camera body 100, the holding part 102 on the camera body 100 side provided with a plurality of contacts is electrically connected to the holding part 202 on the interchangeable lens 200 side provided with a plurality of contacts. Physically connected. Both holders 102 and 202 are used for power supply from the camera body 100 to the interchangeable lens 200 and transmission / reception of signals between the camera body 100 and the interchangeable lens 200.

  An imaging element 104 such as a CMOS or a CCD is provided behind the body side mount 101 in the camera body 100. A release switch 105 is provided above the camera body 100. The user uses the release switch 105 or an operation member (not shown) to give a shooting instruction, a shooting condition setting instruction, or the like to the camera body 100. A slide switch 219 that is a zoom operation member for driving a zoom lens (described later) provided in the interchangeable lens 200 is provided on a side surface (a surface different from the mount surface) of the interchangeable lens 200.

  FIG. 1B is a front view of the slide switch 219. The slide switch 219 is configured to be movable within the movable ranges 220 and 221. The movable range 220 located above FIG. 1B corresponds to the telephoto direction, and the movable range 221 located below FIG. 1B corresponds to the wide-angle direction. The slide switch 219 is configured to be positioned at the center of both the movable ranges 220 and 221 when a force is not applied from the outside by a spring or the like (not shown). When the photographer pushes up the slide switch 219 in the direction of the movable range 220, a zoom lens described later is driven at a speed corresponding to the amount of movement of the slide switch 219, and the focal length of the interchangeable lens 200 changes to the telephoto side. Similarly, when the slide switch 219 is moved in the direction of the movable range 221, the focal length of the interchangeable lens 200 changes to the wide angle side.

  FIG. 2 is a cross-sectional view showing an interchangeable lens type camera system to which the present invention is applied. The interchangeable lens 200 includes an imaging optical system 210 that forms a subject image. The imaging optical system 210 includes a plurality of lenses 210a to 210d disposed on the same optical axis O. The plurality of lenses 210 a to 210 d include a zoom lens 210 b that changes the focal length of the imaging optical system 210 and a focus lens 210 c that adjusts the focus position of the subject image.

  The imaging optical system 210 is a so-called varifocal optical system. That is, when the zoom lens 210b is driven and the focal length of the imaging optical system 210 changes, the relationship between the shooting distance and the position of the focus lens 210c on the optical axis O changes. For example, the zoom lens 210b is located at a position where the focal length of the imaging optical system 210 is 20 mm, and the focus lens is located at a position where the photographing distance is 3 m (the subject is in focus 3 m away from the imaging surface of the image sensor 104). When the zoom lens 210b is driven when the zoom lens 210b is present and the focal length is 40 mm, the shooting distance of the focus lens 210c is not 3 m (for example, 4 m or 6 m). The relationship between the zoom lens 210b and the focus lens 210c will be described in detail later.

  Inside the interchangeable lens 200, a lens control unit 203 that controls each part of the interchangeable lens 200 is provided. The lens control unit 203 includes a microcomputer (not shown) and its peripheral circuits. The lens control unit 203 is connected to a lens side first communication unit 217, a lens side second communication unit 218, a zoom drive unit 212, a focus drive unit 214, a ROM 215, and a RAM 216.

  The lens-side first communication unit 217 and the lens-side second communication unit 218 transmit and receive signals to and from the camera body 100 via the communication contacts of the holding units 102 and 202. The lens side first communication unit 217 and the lens side second communication unit 218 are communication interfaces on the interchangeable lens 200 side, respectively. The lens control unit 203 performs communication (hotline communication, command data communication) described later with the camera body 100 (body control unit 103 described later) using these communication interfaces.

  The zoom driving unit 212 includes a motor (for example, an actuator such as a stepping motor) that generates a driving force and a transmission system (for example, a combination of a plurality of gears) that transmits the driving force to the zoom lens 210b. The zoom driving unit 212 is controlled by the lens control unit 203, and drives the zoom lens 210b in the optical axis O direction at a driving speed designated by the lens control unit 203. That is, the interchangeable lens 200 is a zoom lens having a so-called power zoom function. The focus drive unit 214 has the same configuration as the zoom drive unit 212 except that the drive target is the focus lens 210c.

  The lens control unit 203 is configured to be able to acquire positions on the optical axis O of the zoom lens 210b and the focus lens 210c. For example, an encoder (not shown) may be provided to detect the position of the zoom lens 210b or the focus lens 210c, or an input signal to an actuator (stepping motor or the like) that drives the zoom lens 210b or the focus lens 210c is monitored. By doing so, the position may be detected.

  The ROM 215 is a nonvolatile storage medium and stores a predetermined control program executed by the lens control unit 203 in advance. The RAM 216 is a volatile storage medium and is used as a temporary storage area for various data by the lens control unit 203.

  A shutter 115 for controlling the exposure state of the image sensor 104 and an optical filter 116 combining an optical low-pass filter and an infrared cut filter are provided on the front surface of the image sensor 104. The subject light that has passed through the imaging optical system 210 enters the image sensor 104 via the shutter 115 and the filter 116.

  Inside the camera body 100, a body control unit 103 that controls each part of the camera body 100 is provided. The body control unit 103 includes a microcomputer (not shown), a RAM, and peripheral circuits thereof.

  A body-side first communication unit 117 and a body-side second communication unit 118 are connected to the body control unit 103. The body-side first communication unit 117 is connected to the holding unit 102, and can transmit and receive signals to and from the lens-side first communication unit 217 through a plurality of contacts provided on the holding unit 102. Similarly, the body side second communication unit 118 can transmit and receive signals to and from the lens side second communication unit 218. In other words, each of the body-side first communication unit 117 and the body-side second communication unit 118 is a body-side communication interface. The body control unit 103 performs communication (hotline communication and command data communication) described later with the interchangeable lens 200 (lens control unit 203) using these communication interfaces.

  A display device 111 configured by an LCD panel or the like is disposed on the back surface of the camera body 100. The body control unit 103 displays various menu screens for setting an image of a subject (a so-called through image) based on the output of the image sensor 104, shooting conditions, and the like on the display device 111.

  The lens control unit 203 functionally includes a first drive control unit 203a, a second drive control unit 203b, and a drive state transmission unit 203c. Each of these units is realized by software when the lens control unit 203 executes a predetermined control program stored in the ROM 215. Each of these units can be configured as an electronic circuit having an equivalent function.

  The first drive control unit 203a performs drive control of the focus lens 210c based on the drive command (drive instruction) transmitted from the camera body 100. The second drive control unit 203b performs drive control of the focus lens 210c based on the operation of the slide switch 219. The driving state transmission unit 203 c transmits driving state data to the camera body 100 in response to the state confirmation command transmitted from the camera body 100. The operations of these parts will be described in detail later.

(Description of holding units 102 and 202)
FIG. 3 is a schematic diagram showing details of the holding units 102 and 202. In FIG. 3, the holding portion 102 is arranged on the right side of the body-side mount portion 101 in accordance with an actual mount structure. That is, the holding portion 102 according to the present embodiment is disposed at a location deeper than the mount surface of the body-side mount portion 101 (a location on the right side of the body-side mount portion 101 in FIG. 3). Similarly, the holding unit 202 is arranged on the right side of the lens side mount unit 201 because the holding unit 202 of the present embodiment is arranged at a position protruding from the mount surface of the lens side mount unit 201. Represents. Since the holding unit 102 and the holding unit 202 are arranged in this way, the camera body 100 and the interchangeable lens 200 are mounted by bringing the mounting surface of the body side mounting unit 101 into contact with the mounting surface of the lens side mounting unit 201. When combined, the holding unit 102 and the holding unit 202 are connected, and the electrical contacts provided in both holding units are also connected. Since such a mount structure is well known, further explanation and illustration are omitted.

  As shown in FIG. 3, the holding unit 102 has 12 contacts BP <b> 1 to BP <b> 12. The holding unit 202 has twelve contacts LP1 to LP12 corresponding to the twelve contacts described above.

  The contacts BP1 and BP2 are connected to the first power supply circuit 130 in the camera body 100. The first power supply circuit 130 has a drive system such as an actuator at the contact point BP1 and has a relatively large power consumption (excluding the zoom drive unit 212, the aperture drive unit 213, the focus drive unit 214, etc.) in the interchangeable lens 200. Supply the operating voltage of each part. That is, the operating voltage of each part in the interchangeable lens 200 excluding the above driving parts is supplied from the contact BP1 and the contact LP1. The voltage value that can be supplied to the contact point BP1 has a range between the minimum voltage value and the maximum voltage value (for example, a voltage width in the 3V range). The voltage value that is normally supplied is the maximum voltage value and the minimum voltage value. Is a voltage value in the vicinity of the intermediate value. As a result, the current value supplied from the camera body 100 side to the interchangeable lens 200 side is a current value within a range of about several tens mA to several hundreds mA in the power-on state.

  The contact BP2 is a ground terminal corresponding to the operating voltage given to the contact BP1. That is, the contact BP2 and the contact LP2 are ground terminal voltages corresponding to the above operating voltage.

  In the following description, the signal line constituted by the contact point BP1 and the contact point LP1 is referred to as a signal line V33. A signal line constituted by the contact point BP2 and the contact point LP2 is referred to as a signal line GND. These contacts LP1, LP2, BP1, BP2 constitute a power supply system contact for supplying power from the camera body 100 side to the interchangeable lens 200 side.

  The contacts BP3, BP4, BP5, and BP6 are connected to the body-side first communication unit 117. The contact points LP3, LP4, LP5, and LP6 on the interchangeable lens 200 side corresponding to these contact points are connected to the lens-side first communication unit 217. The body-side first communication unit 117 and the lens-side first communication unit 217 transmit and receive signals to and from each other using these contacts (communication system contacts). The contents of communication performed by the body-side first communication unit 117 and the lens-side first communication unit 217 will be described in detail later.

  In the following description, a signal line constituted by the contact BP3 and the contact LP3 is referred to as a signal line CLK. Similarly, the signal line constituted by the contact BP4 and the contact LP4 is signal line BDAT, the signal line constituted by the contact BP5 and the contact LP5 is signal line LDAT, and the signal line constituted by the contact BP6 and the contact LP6 is signaled. Called line RDY.

  The contacts BP7, BP8, BP9, and BP10 are connected to the body-side second communication unit 118. The contacts LP7, LP8, LP9, and LP10 on the interchangeable lens 200 side corresponding to these contacts are connected to the lens-side second communication unit 218. The lens-side second communication unit 218 transmits signals to the body-side second communication unit 118 using these contacts (communication system contacts). The contents of communication performed by the body-side second communication unit 118 and the lens-side second communication unit 218 will be described in detail later.

  In the following description, a signal line constituted by the contact BP7 and the contact LP7 is referred to as a signal line HREQ. Similarly, a signal line composed of the contact point BP8 and the contact point LP8 is signal line HANS, a signal line composed of the contact point BP9 and the contact point LP9 is signal line HCLK, and a signal line composed of the contact point BP10 and the contact point LP10 is signaled. Called line HDAT.

  The contact BP11 and the contact BP12 are connected to the second power supply circuit 131 in the camera body 100. The second power supply circuit 131 supplies a driving voltage of a circuit (zoom driving unit 212, aperture driving unit 213, focus driving unit 214, etc.) having a driving system such as an actuator and a relatively large power consumption to the contact point BP12. That is, the drive voltages of the zoom drive unit 212, the aperture drive unit 213, and the focus drive unit 214 are supplied from the contact point BP12 and the contact point LP12. The voltage value that can be supplied to the contact point BP12 has a range from the minimum voltage value to the maximum voltage value, all of which are larger than the voltage value range that can be supplied to the contact point BP1 (for example, The maximum voltage value that can be supplied to the contact point BP12 is several times the maximum voltage value that can be supplied to the contact point BP1). That is, the voltage value supplied to the contact point BP12 is a voltage value whose magnitude is different from the voltage value supplied to the contact point BP1. The voltage value that is normally supplied to the contact BP12 is a voltage value in the vicinity of an intermediate value between the maximum voltage value and the minimum voltage value that can be supplied to the contact BP12. As a result, the current supplied from the camera body 100 side to the interchangeable lens 200 side has a current value of about 10 mA to several A in the power-on state.

  The contact BP11 is a ground terminal corresponding to the drive voltage given to the contact BP12. That is, the contact BP11 and the contact LP11 are ground terminals corresponding to the drive voltage.

  In the following description, a signal line constituted by the contact BP11 and the contact LP11 is referred to as a signal line PGND. A signal line constituted by the contact BP12 and the contact LP12 is referred to as a signal line BAT. These contacts LP11, LP12, BP11, BP12 constitute a power supply system contact for supplying power from the camera body 100 side to the interchangeable lens 200 side.

  As is apparent from the magnitude relationship between the voltage value (current value) supplied to the contacts BP12 and LP12 and the voltage value (current value) supplied to the contacts BP1 and LP1, the voltages are supplied to the contacts. The difference between the maximum value and the minimum value of the current flowing through the contact point BP11 and the contact point LP11 serving as the ground terminals for each of the voltages is larger than the difference between the maximum value and the minimum value of the current flowing through the contact points BP2 and LP2. ing. This is because the power consumed by each drive unit having a drive system such as an actuator is larger than that of an electronic circuit such as the lens control unit 203 in the interchangeable lens 200, and the driven parts driven by these drive units. When it is not necessary to drive a member, it depends on each drive part not consuming electric power.

(Description of command data communication)
The lens control unit 203 controls the lens-side first communication unit 217 and receives control data from the body-side first communication unit 117 via the contacts LP3 to LP6, that is, the signal lines CLK, BDAT, LDAT, and RDY. Reception and transmission of response data to the body-side first communication unit 117 are performed in parallel at a first predetermined cycle (for example, 16 milliseconds in this embodiment). Hereinafter, details of communication performed between the lens-side first communication unit 217 and the body-side first communication unit 117 will be described.

  In the present embodiment, communication performed between the lens control unit 203 and the lens-side first communication unit 217 and the body control unit 103 and the body-side first communication unit 117 is referred to as “command data communication”. A transmission line composed of four signal lines (signal lines CLK, BDAT, LDAT, and RDY) used for command data communication is referred to as a first transmission line.

  FIG. 4 is a timing chart showing an example of command data communication. The body control unit 103 and the body-side first communication unit 117 first check the signal level of the signal line RDY at the start of command data communication (T1). The signal level of the signal line RDY indicates whether the lens-side first communication unit 217 can communicate. The lens control unit 203 and the lens-side first communication unit 217 output a signal of H (High) level from the contact LP6 when communication is not possible. That is, the signal level of the signal line RDY is set to H level. When the signal line RDY is at the H level, the body control unit 103 and the body-side first communication unit 117 do not start communication until the signal line RDY is at the L level. Also, the next processing during communication is not executed.

  If the signal line RDY is at L (Low) level, the body control unit 103 and the first body side communication unit 117 output the clock signal 401 from the contact point BP3. That is, the clock signal 401 is transmitted to the first lens side communication unit 217 via the signal line CLK. In synchronization with the clock signal 401, the body control unit 103 and the body side first communication unit 117 output a body side command packet signal 402, which is the first half of the control data, from the contact point BP4. That is, the body side command packet signal 402 is transmitted to the first lens side communication unit 217 via the signal line BDAT.

  When the clock signal 401 is output to the signal line CLK, the lens control unit 203 and the lens-side first communication unit 217 synchronize with the clock signal 401, and the lens-side command packet that is the first half of the response data from the contact LP5. The signal 403 is output. That is, the lens-side command packet signal 403 is transmitted to the first body-side communication unit 117 via the signal line LDAT.

The lens control unit 203 and the lens side first communication unit 217 set the signal level of the signal line RDY to the H level in response to the completion of transmission of the lens side command packet signal 403 (T2). The lens control unit 203 starts a first control process 404 (described later) that is a process according to the content of the received body-side command packet signal 402.

  When the first control process 404 is completed, the lens control unit 203 notifies the lens side first communication unit 217 of the completion of the first control process 404. In response to this notification, the lens side first communication unit 217 outputs an L level signal from the contact LP6. That is, the signal level of the signal line RDY is set to L level (T3). The body control unit 103 and the first body side communication unit 117 output the clock signal 405 from the contact point BP3 in accordance with the change in the signal level. That is, the clock signal 405 is transmitted to the lens side first communication unit 217 via the signal line CLK.

  The body control unit 103 and the first body-side communication unit 117 output a body-side data packet signal 406 that is the latter half of the control data from the contact point BP4 in synchronization with the clock signal 405. That is, the body side data packet signal 406 is transmitted to the lens side first communication unit 217 via the signal line BDAT.

  When the clock signal 405 is output to the signal line CLK, the lens control unit 203 and the lens-side first communication unit 217 synchronize with the clock signal 405, and the lens-side data packet signal that is the latter half of the response data from the contact LP5. 407 is output. That is, the lens-side data packet signal 407 is transmitted to the first body-side communication unit 117 via the signal line LDAT.

  In response to the completion of transmission of the lens-side data packet signal 407, the lens control unit 203 and the lens-side first communication unit 217 set the signal level of the signal line RDY to the H level again (T4). The lens control unit 203 starts a second control process 408 (described later) that is a process according to the content of the received body-side data packet signal 406.

  Here, the first control process 404 and the second control process 408 performed by the lens control unit 203 will be described.

  For example, a case where the received body-side command packet signal 402 has a content requesting specific data on the interchangeable lens side will be described. As the first control process 404, the lens control unit 203 analyzes the content of the body-side command packet signal 402 and executes a process of generating the requested specific data. Further, as the first control process 404, the lens control unit 203 uses the checksum data included in the command packet signal 402 to easily determine whether there is an error in the communication of the command packet signal 402 from the number of data bytes. The communication error check process to check is also executed. The specific data signal generated in the first control process 404 is output to the body side as a lens-side data packet signal 407. In this case, the body side data packet signal 406 output from the body side after the command packet signal 402 is a dummy data signal (including checksum data) that has no particular meaning for the lens side. In this case, the lens control unit 203 executes the communication error check process as described above using the checksum data included in the body side data packet signal 406 as the second control process 408.

  For example, a case where the received body-side command packet signal 402 is an instruction to drive a lens-side driven member will be described. For example, a case where the command packet signal 402 is an instruction to drive the focus lens 210c and the received body side data packet signal 406 is the drive amount of the focus lens 210c will be described. As the first control process 404, the lens control unit 203 analyzes the content of the command packet signal 402 and generates an acknowledgment signal indicating that the content has been understood. Furthermore, the lens control unit 203 also executes the communication error check process as described above using the checksum data included in the command packet signal 402 as the first control process 404. The acknowledge signal generated in the first control process 404 is output to the body side as a lens side data packet signal 407. In addition, as the second control process 408, the lens control unit 203 executes an analysis process of the contents of the body side data packet signal 406 and uses the checksum data included in the body side data packet signal 406 as described above. Execute the check process.

  When the second control process 408 is completed, the lens control unit 203 notifies the lens side first communication unit 217 of the completion of the second control process 408. Accordingly, the lens control unit 203 causes the lens side first communication unit 217 to output an L level signal from the contact LP6. That is, the signal level of the signal line RDY is set to L level (T5).

  If the received body-side command packet signal 402 is an instruction to drive the lens-side driven member (for example, the focus lens 210c) as described above, the lens control unit 203 notifies the lens-side first communication unit 217. While the signal level of the signal line RDY is set to the L level, the focus driving unit 214 is caused to execute processing for driving the focus lens 210c by the driving amount.

  The communication performed at the above-described time T1 to time T5 is one command data communication. As described above, in one command data communication, body control unit 103 and body side first communication unit 117 transmit body side command packet signal 402 and body side data packet signal 406 one by one. In other words, the body side command packet signal 402 and the body side data packet signal 406 together constitute one control data although it is divided and transmitted for convenience of processing.

  Similarly, in one command data communication, the lens control unit 203 and the lens side first communication unit 217 transmit the lens side command packet signal 403 and the lens side data packet signal 407 one by one. That is, the lens side command packet signal 403 and the lens side data packet signal 407 are combined to form one response data.

  As described above, the lens control unit 203 and the lens-side first communication unit 217 perform reception of control data from the body-side first communication unit 117 and transmission of response data to the body-side first communication unit 117 in parallel. And do it. The contact LP6 and the contact BP6 used for command data communication are contacts through which asynchronous signals (signal level of the signal line RDY / H (High) level or L (Low) level) that are not synchronized with other clock signals are transmitted. is there.

(Description of hotline communication)
The lens control unit 203 controls the lens side second communication unit 218 to transmit lens position data to the body side second communication unit 118 via the contacts LP7 to LP10, that is, the signal lines HREQ, HANS, HCLK, and HDAT. Send. Hereinafter, details of communication performed between the lens-side second communication unit 218 and the body-side second communication unit 118 will be described.

  In the present embodiment, communication performed between the lens control unit 203 and the lens-side second communication unit 218, and the body control unit 103 and the body-side second communication unit 118 is referred to as “hotline communication”. A transmission line composed of four signal lines (signal lines HREQ, HANS, HCLK, and HDAT) used for hot line communication is referred to as a second transmission line.

  FIG. 5 is a timing chart showing an example of hotline communication. The body control unit 103 of the present embodiment is configured to start hot line communication every second predetermined period (for example, 1 millisecond in the present embodiment). This period is shorter than the period for performing command data communication. FIG. 5A is a diagram illustrating a state in which hot line communication is repeatedly performed at predetermined intervals Tn. FIG. 5B shows a state in which a certain communication period Tx is expanded in hot line communication repeatedly executed. Hereinafter, the procedure of hotline communication will be described based on the timing chart of FIG.

  At the start of hot line communication (T6), body control unit 103 and body-side second communication unit 118 first output an L level signal from contact point BP7. That is, the signal level of the signal line HREQ is set to L level. The lens side second communication unit 218 notifies the lens control unit 203 that this signal has been input to the contact LP7. In response to this notification, the lens control unit 203 starts executing a generation process 501 that generates lens position data. The generation process 501 is a process in which the lens control unit 203 causes the focusing lens position detection unit (not shown) to detect the position of the focus lens 210c and generates lens position data representing the detection result.

  When the lens control unit 203 completes the generation process 501, the lens control unit 203 and the lens-side second communication unit 218 output an L level signal from the contact LP8 (T7). That is, the signal level of the signal line HANS is set to the L level. The body control unit 103 and the body-side second communication unit 118 output the clock signal 502 from the contact BP9 in response to the input of this signal to the contact BP8. That is, a clock signal is transmitted to the lens side second communication unit 218 via the signal line HCLK.

  The lens control unit 203 and the second lens-side communication unit 218 output a lens position data signal 503 representing lens position data from the contact LP10 in synchronization with the clock signal 502. That is, the lens position data signal 503 is transmitted to the body-side second communication unit 118 via the signal line HDAT.

  When the transmission of the lens position data signal 503 is completed, the lens control unit 203 and the second lens side communication unit 218 output an H level signal from the contact LP8. That is, the signal level of the signal line HANS is set to the H level (T8). The body-side second communication unit 118 outputs an H-level signal from the contact LP7 in response to the input of this signal to the contact BP8. That is, the signal level of the signal line HREQ is set to H level (T9).

  The communication performed from time T6 to time T9 described above is one hot line communication. As described above, in one hot line communication, one lens position data signal 503 is transmitted by the lens control unit 203 and the second lens side communication unit 218. The contacts LP7, LP8, BP7, and BP8 used for hotline communication are contacts through which asynchronous signals that are not synchronized with other clock signals are transmitted. That is, the contacts LP7 and BP7 are contacts through which asynchronous signals (signal level HREQ signal level / H (High) level or L (Low) level) are transmitted, and the contacts LP8 and BP8 are asynchronous signals (signal line HANS). Signal level / H (High) level or L (Low) level).

  Note that the command data communication and the hotline communication can be executed simultaneously or partially in parallel. That is, one of the lens side first communication unit 217 and the lens side second communication unit 218 can communicate with the camera body 100 even when the other is communicating with the camera body 100. is there.

(Explanation of zoom control)
The body control unit 103 is configured to be able to transmit a zoom drive command to the lens control unit 203 by command data communication. The zoom drive command is a command including at least a focal length. The ROM 215 in the interchangeable lens 200 stores a table indicating the correspondence between the position of the zoom lens 210b on the optical axis O and a predetermined focal length. When the second drive control unit 203b receives this zoom drive command, the second drive control unit 203b refers to the above table and acquires the position of the zoom lens 210b corresponding to the focal length specified by the zoom drive command. Then, the zoom driving unit 212 is controlled so that the zoom lens 210b is driven to the acquired position. As a result, the focal length of the imaging optical system 210 becomes the focal length specified by the zoom drive command.

  When the photographer operates the zoom operation member (slide switch 219) of the interchangeable lens 200, the lens control unit 203 causes the position information (in other words, the position of the slide switch 219 according to the operation to the zoom operation member (slide switch 219)). Then, information for designating the zooming direction and zooming speed of the zoom lens) is transmitted to the body control unit 103 on the camera body side via the command data communication system. Based on the position information of the slide switch 219 received from the interchangeable lens 200, the body control unit 103 generates zoom command data (zoom drive command) indicating a zooming instruction for the interchangeable lens 200. Specifically, the camera body 100 is previously provided with table information corresponding to the position information of the zoom operation member (slide switch 219). This table information correlates the operation position of the slide switch 219 with the contents of commands for the zoom lens 210b (zooming directions such as tele and wide directions and zooming speeds such as high speed, medium speed and low speed). And the body control part 103 will transmit the zoom drive command which should be transmitted to the interchangeable lens 200 to the lens control part 203 using a command data communication system.

  FIG. 6 is a diagram showing the positional relationship between the zoom lens 210b and the focus lens 210c. Curves L0 to L4 shown in FIG. 6 represent a zoom position corresponding to a specific shooting distance and a position on the optical axis of the focus lens 210c (a focusing lens position focused on each shooting distance). It is. The horizontal axis corresponds to the zoom position, and the vertical axis corresponds to the position (focusing lens position) on the optical axis O of the focus lens 210c. The zoom position is a discrete position that is set in advance in the interchangeable lens 200 and is a target to which the body control unit 103 moves the zoom lens 210b. The lens control unit 203 can acquire the position of the zoom lens 210b more finely than the zoom position shown in FIG.

  A predetermined focal length corresponds to each zoom position indicated by an integer of 0 to 5 in FIG. When the body control unit 103 transmits a zoom drive command, the zoom lens 210b selects a zoom position corresponding to the focal length specified by the zoom drive command from the zoom positions indicated by numerical values 0 to 5 in FIG. Then, the zoom lens 210b is driven to a position on the optical axis O corresponding to the zoom position.

  Since the imaging optical system 210 of this embodiment is a so-called varifocal optical system, as shown in FIG. 6, in order to keep the photographing distance constant when driving the zoom lens 210b, the zoom lens 210b is driven. Accordingly, it is necessary to drive the focus lens 210c. For example, in FIG. 6, the curve L0 represents the position of the focus lens 210c corresponding to the shooting distance at infinity. Similarly, curves L1, L2, L3, and L4 represent the positions of the focus lens 210c corresponding to specific shooting distances (for example, 6 m, 3 m, 1 m, 50 cm, etc.) in order from the infinity side.

  When the zoom position is 1, if the focus lens 210c is at the position represented by P (0, 1) in FIG. 6, the imaging distance of the imaging optical system 210 is infinite. That is, the imaging optical system 210 is in a state in which a subject located at infinity is in focus. In FIG. 6, points corresponding to the mth shooting distance and the kth zoom position are represented in the form of P (m, k). Similarly, in the following description, a point corresponding to the shooting distance m and the zoom position k is expressed as P (m, k).

  When the zoom lens 210b is driven so that the zoom position is larger than 1, the focus lens 210c must be driven along the curve L0 in order to keep the shooting distance at infinity. For example, when the zoom position is 3, when the zoom position is 3, the focus lens 210c is at the position P (0,3) so that the focus lens 210c is at the position P (0,2) when the zoom position is 2. Thus, the focus lens 210c must be driven.

  The ROM 215 in the interchangeable lens 200 stores discrete points on the curves L0 to L4 shown in FIG. Specifically, the coordinates of points corresponding to the zoom positions of the curves L0 to L4 and 0 to 5 (points indicated in the form of P (m, k) in FIG. 6) are stored together with the shooting distance of the curve. ing. That is, the ROM 215 stores the position (focusing lens position) of the focus lens 210c corresponding to the plurality of shooting distances for each of the positions of the plurality of zoom lenses 210b. In the following description, the position of the focus lens 210c stored in the ROM 215 is referred to as position information (or simply position information) of the focus lens 210c.

  Note that FIG. 6 shows curves L0 to L4 corresponding to five shooting distances and six zoom positions 0 to 5, respectively, but this is a part of the position information stored in the ROM 215 for explanation. This is only shown, and actually, position information corresponding to a larger number of shooting distances and zoom positions is stored.

  When driving the zoom lens 210b, the second drive control unit 203b performs so-called zoom tracking in which the focus lens 210c is driven in parallel so that the photographing distance is maintained. As a result, the user can perform a zoom operation as if the user has an optical system that is not varifocal, even though the interchangeable lens 200 has a varifocal optical system. Zoom tracking is drive control that changes the focal length of the imaging optical system 210 while keeping the shooting distance constant by driving the zoom lens 210b and the focus lens 210c in parallel.

(Description of automatic focus adjustment process)
When the user performs a predetermined AF operation (for example, a half-press operation of the release switch 105), the body control unit 103 executes a so-called contrast detection type automatic focus adjustment process. In the contrast detection type automatic focus adjustment process, the focus lens 210c is driven while performing a known contrast detection calculation using the imaging signal output from the imaging element 104, and the focus evaluation value (contrast value) reaches a peak. In this process, automatic focus adjustment is performed by detecting the position 210c.

  The lens control unit 203 corresponds to three types of drive instructions, ie, a first drive command, a second drive command, and a third drive command, for automatic focus adjustment processing. When the body control unit 103 transmits each of these drive commands to the lens control unit 203 by command data communication, the first drive control unit 203a executes drive control of the focus lens 210c.

  The first drive command is a command for driving the focus lens 210c to the initial position of the automatic focus adjustment process. The initial position of the automatic focus adjustment process is, for example, a close position or an infinite position. When the lens-side first communication unit 217 receives the first drive command, the first drive control unit 203a drives the focus lens 210c to a predetermined initial position.

  The second drive command is a command for executing a so-called scan operation for driving the focus lens 210c in a predetermined scan range. When the lens-side first communication unit 217 receives the second drive command, the first drive control unit 203a drives the focus lens 210c within a predetermined scan range. At this time, the first drive control unit 203a drives the focus lens 210c so that the image plane moving speed of the subject image is constant.

  The third drive command is a command for driving the focus lens 210c to the designated absolute position. The third drive command includes absolute position information of the focus lens 210c as a control parameter. When the lens-side first communication unit 217 receives the third drive command, the first drive control unit 203a drives the focus lens 210c to the designated absolute position.

  These three types of drive commands include an identifier as a control parameter. The identifier is a unique identifier for each drive command, and is an integer value of 0 or more, for example. Each time the drive command is sent, the body control unit 103 assigns a different integer value to the drive command as an identifier.

  For example, it is assumed that the body control unit 103 transmits the first drive command with the identifier “1” to the lens control unit 203 at a certain time. Thereafter, when the body control unit 103 transmits the first drive command to the lens control unit 203 at a different time, the body control unit 103 indicates an identifier (for example, “1” different from “1”) in the first drive command. 2 ").

  Note that although the identifier is unique for each drive command, the identifier need not be unique before and after the camera body 100 is powered off. Also, the identifier need not be unique before and after a very long period. For example, when the identifier is a 16-bit unsigned integer value, the identifier takes a value from 0 to 65535. When these 65536 integer values are sequentially used as identifiers, the 65537th drive command has the same identifier as the first drive command, but even such an identifier is used in the present invention. Is sufficiently unique.

  In addition to the three types of drive commands described above, the lens control unit 203 further corresponds to a state confirmation command. The lens control unit 203 further corresponds to a state confirmation command. When the body control unit 103 transmits a state confirmation command to the lens control unit 203 by command data communication, the drive state transmission unit 203c accordingly responds to the drive state data indicating the current drive control state of the first drive control unit 203a. It transmits to the body control part 103. The drive control state of the first drive control unit 203 a is an execution state of the three types of drive commands transmitted from the body control unit 103.

  When the first drive control unit 203 a is executing the drive command transmitted from the body control unit 103, the drive state transmission unit 203 c transmits the first drive state data to the body control unit 103. That is, the first driving state data is driving state data indicating that a driving command is being executed.

  When the first drive control unit 203 a has completed the execution of the drive command transmitted from the body control unit 103, the drive state transmission unit 203 c transmits the second drive state data to the body control unit 103. That is, the second driving state data is driving state data indicating that the execution of the driving command is completed.

  In addition, there is drive state data called third drive state data. This will be described in detail later.

  There may be a slight time lag from when the drive command is received until the focus lens 210c is actually started to be driven. When the state confirmation command is received during the time lag, the driving state transmission unit 203 c transmits the first driving state data to the body control unit 103. That is, even when the first driving state data is transmitted, the focus lens 210c may be stopped instead of being driven.

  Each of the first to third drive state data includes an identifier included in the drive command transmitted from the body control unit 103. For example, when the body control unit 103 transmits a drive command including the identifier “1”, and then the body control unit 103 transmits a state confirmation command, the drive state transmission unit 203c transmits the drive state data including the identifier “1”. It transmits to the body control part 103. The body control unit 103 can easily identify which drive command the first drive control unit 203a is executing (or whether the execution has been completed) by confirming the identifier included in the received drive state data. Can do.

  Next, a procedure for automatic focus adjustment using the first to third drive commands and the state confirmation command will be described.

  FIG. 7 is a time chart of the automatic focus adjustment process. First, at time T <b> 10, the body control unit 103 transmits a first drive command to the lens control unit 203. The identifier of this first drive command is “3”. The first drive control unit 203a starts drive control of the focus lens 210c (drive to a predetermined initial position) in response to the first drive command.

  Thereafter, the body control unit 103 transmits a state confirmation command to the lens control unit 203 every predetermined period (for example, every 1 millisecond), and tracks the execution state of the first drive command transmitted at time T10. In FIG. 7, the first driving state data with the identifier “3” is transmitted from the driving state transmitting unit 203 c in response to the state confirmation command transmitted at time T <b> 11. Therefore, the body control unit 103 determines that the first drive command is still being executed at the time T11.

  Thereafter, in response to the state confirmation command transmitted at time T12, the first driving state data with the identifier “3” is transmitted from the driving state transmitting unit 203c. Accordingly, the body control unit 103 determines that the first drive command is still being executed at the time T12.

  Thereafter, in response to the state confirmation command transmitted at time T13, the second driving state data with the identifier “3” is transmitted from the driving state transmitting unit 203c. The body control unit 103 determines from the second drive state data that the drive control by the first drive control unit 203a has been completed, that is, the focus lens 210c has moved to the initial position. In response to this, the body control unit 103 transmits the second drive command having the identifier “4” at time T14. The first drive control unit 203a starts scan drive of the focus lens 210c in response to the second drive command.

  In parallel with the scan drive, the body control unit 103 performs imaging by the image sensor 104 and contrast detection calculation based on an image signal output from the image sensor 104 by the imaging at predetermined intervals. The body control unit 103 further transmits a state confirmation command every predetermined period. Note that the execution period of the contrast detection calculation and the transmission period of the state confirmation command may be the same or different. In FIG. 7, the state confirmation command is transmitted at times T15 and T16, and the first driving state data with the identifier “4” is received accordingly.

  It is assumed that the peak of the contrast value, that is, the in-focus position is found at time T17. When the in-focus position is found, the body control unit 103 transmits a third drive command for driving the focus lens 210c to the in-focus position. In FIG. 7, the third drive command with the identifier “5” is transmitted at time T17. At time T17, the first drive control unit 203a is executing the second drive command. However, since a new third drive command is received, the second drive command currently being executed is canceled and newly received. Drive control based on the third drive command is started.

  The body control unit 103 continues to transmit a state confirmation command every predetermined period (time T18, T19), and waits for the completion of execution of the third drive command. Since the second driving state data with the identifier “5” is received at time T19, the body control unit 103 completes the automatic focus adjustment processing at time T19.

  FIG. 8 is a flowchart of automatic focus adjustment processing executed by the body control unit 103 and the lens control unit 203. First, the automatic focus adjustment process executed by the body control unit 103 shown on the left side of the drawing will be described.

  In step S <b> 100, the body control unit 103 transmits a first drive command to the lens control unit 203. In step S110, the body control unit 103 executes a preparatory process for the automatic focus adjustment process. The preparatory process includes, for example, a process of switching the frame rate of the image sensor 104 to a frame rate for automatic focus adjustment.

  In step S <b> 120, the body control unit 103 transmits a state confirmation command to the lens control unit 203. In step S <b> 130, the body control unit 103 receives drive state data from the lens control unit 203. In step S140, the body control unit 103 determines whether or not the drive control by the first drive control unit 203a is completed, that is, whether or not the drive state data received in step S130 is the second drive state data. If the drive control has not been completed, the body control unit 103 advances the process to step S120. On the other hand, when the drive control is completed, the body control unit 103 advances the process to step S150.

  In step S150, the body control unit 103 transmits the second drive command to the lens control unit 203. In step S <b> 160, the body control unit 103 transmits a state confirmation command to the lens control unit 203. In step S <b> 170, the body control unit 103 receives drive state data from the lens control unit 203. In step S180, the body control unit 103 determines whether or not the drive control by the first drive control unit 203a is completed, that is, whether or not the drive state data received in step S170 is the second drive state data. If the drive control has not been completed, the body control unit 103 advances the process to step S190.

  In step 190, the body control unit 103 calculates a focus evaluation value (contrast amount) based on the imaging signal output from the imaging element 104. In step S200, the body control unit 103 determines whether or not the position of the focus lens 210c at which the focus evaluation value reaches a peak, that is, the in-focus position is found. If the in-focus position has not been found, the body control unit 103 advances the process to step S160. On the other hand, when the in-focus position is found, the body control unit 103 advances the process to step S210.

  In step S <b> 210, the body control unit 103 transmits a third drive command to the lens control unit 203. In step S <b> 220, the body control unit 103 transmits a state confirmation command to the lens control unit 203. In step S230, the body control unit 103 receives the driving state data from the lens control unit 203. In step S240, the body control unit 103 determines whether or not the drive control by the first drive control unit 203a is completed, that is, whether or not the drive state data received in step S230 is the second drive state data. If the drive control has not been completed, the body control unit 103 advances the process to step S220. On the other hand, when the drive control is completed, the body control unit 103 ends the automatic focus adjustment process.

  In step S180, when the drive control is completed, that is, when the scanning operation is performed but the in-focus position cannot be found, the body control unit 103 ends the automatic focus adjustment process. At this time, the body control unit 103 may be configured to drive the focus lens 210c to a predetermined position (for example, infinity).

  Next, the automatic focus adjustment process executed by the lens control unit 203 shown on the right side of FIG. 8 will be described. First, in step S <b> 300, the lens side first communication unit 217 receives a first drive command from the body control unit 103. In step S310, the first drive control unit 203a starts drive control for driving the focus lens 210c to the initial position.

  In step S <b> 320, the lens side first communication unit 217 receives a state confirmation command from the body control unit 103. In step S330, the driving state transmission unit 203c transmits the driving state data to the body control unit 103. In step S340, the first drive control unit 203a determines whether drive control based on the first drive command received in step S300 is completed. If drive control has not been completed, the first drive control unit 203a advances the process to step S320. On the other hand, if the drive control has been completed, the first drive control unit 203a advances the process to step S350.

  In step S350, the lens side first communication unit 217 receives the second drive command from the body control unit 103. In step S360, the first drive control unit 203a starts scan driving of the focus lens 210c. In step S <b> 370, the first lens-side communication unit 217 receives a state confirmation command from the body control unit 103. In step S380, the driving state transmission unit 203c transmits the driving state data to the body control unit 103. In step S390, the first drive control unit 203a determines whether or not drive control based on the second drive command received in step S350 is completed. If the drive control has been completed, the first drive control unit 203a ends the automatic focus adjustment process. On the other hand, if the drive control is not completed, the first drive control unit 203a advances the process to step S400.

  In step S <b> 400, the lens side first communication unit 217 determines whether a third drive command is received from the body control unit 103. If the third drive command has not been received, the lens side first communication unit 217 advances the process to step S370. On the other hand, if the third drive command has been received, the lens-side first communication unit 217 advances the process to step S410.

  In step S410, the first drive control unit 203a starts driving the focus lens 210c to the position specified by the third drive command received in step S400. In step S <b> 420, the lens side first communication unit 217 receives a state confirmation command from the body control unit 103. In step S430, the driving state transmission unit 203c transmits the driving state data to the body control unit 103. In step S440, the first drive control unit 203a determines whether drive control based on the third drive command received in step S400 is completed. If drive control has not been completed, the first drive control unit 203a advances the process to step S420. On the other hand, if the drive control has been completed, the first drive control unit 203a ends the automatic focus adjustment process.

(Explanation of competition between autofocus processing and zoom control)
Next, zoom control performed during execution of the automatic focus adjustment process will be described. As described above, the imaging optical system 210 of this embodiment is a so-called varifocal optical system, and the second drive control unit 203b drives the focus lens 210c in parallel with the drive of the zoom lens 210b. In the following description, the case of performing a zoom operation / zoom tracking operation by a slide switch operation (that is, a zoom tracking operation accompanying a power zoom operation) will be described. However, a zoom operation by an operation of a zoom operation ring provided on an interchangeable lens is described. The same applies to a zoom tracking operation (a zoom tracking operation associated with a so-called manual zoom operation (rotation operation)).

  In the present embodiment, the drive control by the second drive control unit 203b is executed with priority over the drive control by the first drive control unit 203a. For example, when the user operates the slide switch 219 when the body control unit 103 starts executing the automatic focus adjustment process and the first drive control unit 203a executes any one of the first to third drive commands. The second drive control unit 203b performs so-called zoom tracking after stopping the drive control by the first drive control unit 203a.

  The drive state transmission unit 203c transmits the third drive state data to the body control unit 103 when the drive control of the first drive control unit 203a is stopped by the second drive control unit 203b. That is, the third drive state data is drive state data indicating that the drive control of the first drive control unit 203a is stopped by the second drive control unit 203b.

  When the body control unit 103 receives the third driving state data from the driving state transmission unit 203c, the body control unit 103 stops the automatic focus adjustment process being executed. Thereafter, when the user performs the AF operation again, the body control unit 103 restarts the automatic focus adjustment process from the beginning.

  The drive state transmission unit 203c transmits the third drive state data even when the drive control by the second drive control unit 203b is started after the drive control of the first drive control unit 203a is completed. To do. This is because when the drive control by the second drive control unit 203b is started, the focus lens 210c is moved from the position at the time when the drive control by the first drive control unit 203a is completed. This is because the position is not likely to be the position expected by the body control unit 103.

  For example, it is assumed that the body control unit 103 transmits a first drive command, and the first drive control unit 203a drives the focus lens 210c to a predetermined initial position. After the drive control by the first drive control unit 203a is completed and the focus lens 210c reaches the initial position, if the second drive control unit 203b executes zoom tracking, the focus control unit 210c is moved by the body control unit 103. It moves to a position different from the expected initial position. Therefore, when viewed from the body control unit 103, even when the drive control of the first drive control unit 203a is stopped by the second drive control unit 203b, the drive control of the first drive control unit 203a is completed. However, the original automatic focus adjustment process must be stopped after all.

According to the camera system according to the first embodiment described above, the following operational effects can be obtained.
(1) The focus lens 210c is a driven member that changes its state upon receiving a driving force. The lens side first communication unit 217 (drive instruction receiving means) sequentially receives a drive command (drive instruction signal) indicating a drive instruction of the focus lens 210c from the camera body 100. The first drive control unit 203a performs drive control (first drive control) of the focus lens 210c based on the drive command received by the lens side first communication unit 217. The lens side first communication unit 217 (confirmation request receiving means) receives from the camera body 100 a state confirmation command (state confirmation signal) indicating a confirmation request for the drive control state of the first drive control unit 203a. The driving state transmission unit 203c (driving state transmission unit) receives driving state data (driving state signal) indicating the driving control state of the first driving control unit 203a in response to the reception of the state confirmation command by the lens-side first communication unit 217. Is transmitted to the camera body 100. The drive command includes a unique identifier for each drive command. The driving state transmission unit 203c transmits driving state data including an identifier included in the driving command received by the lens side first communication unit 217. Since it did in this way, it can be checked from a camera body which driving instruction | indication is operating according to the interchangeable lens now.

(2) The drive state transmission unit 203c is second drive state data indicating that drive control based on the drive command is completed, and first drive state data indicating that drive control based on the drive command is not completed. And send either. Since it did in this way, it can be checked from a camera body whether the interchangeable lens completed the drive control based on a drive instruction, or is performing. Unlike simply confirming the driving state of the focus lens 210c, the driving command is being executed even during the period from when the driving command is received until the driving of the focus lens 210c is actually started. It is possible to grasp with certainty.

(3) The second drive control unit 203b (second drive control unit) is driven differently from the drive control (first drive control) of the focus lens 210c by the first drive control unit 203a according to the operation of the slide switch 219. Control (second drive control) is performed. When the slide switch 219 is operated while the first drive control unit 203a is performing drive control, the second drive control unit 203b performs drive control after stopping the drive control by the first drive control unit 203a. . When the drive control by the first drive control unit 203a is stopped by the second drive control unit 203b, the drive state transmission unit 203c has stopped the drive control of the first drive control unit 203a by the second drive control unit 203b. The third driving state data indicating that is transmitted. Since it did in this way, when interrupted by the 2nd drive control part 203b, it will not misidentify that the drive control based on a drive command was completed.

(4) The drive state transmission unit 203c is also configured by the second drive control unit 203b even when the drive control by the second drive control unit 203b is started after the drive control by the first drive control unit 203a is completed. Third drive state data indicating that the drive control of the drive control unit 203a is stopped is transmitted. Thus, even when the current position of the focus lens 210c deviates from the expected position as a result of the drive control performed by the second drive control unit 203b, the accuracy of the automatic focus adjustment process does not decrease.

(5) The imaging optical system 210 is a varifocal optical system, and the second drive control unit 203b performs so-called zoom tracking. Since it did in this way, zoom tracking can be operated with priority over the automatic focus adjustment processing, and the operability of the interchangeable lens 200 is improved.

  The following modifications are also within the scope of the present invention, and one or a plurality of modifications can be combined with the above-described embodiment.

(Modification 1)
The present invention can also be applied to a camera system different from that shown in FIG. For example, the present invention can be applied to a so-called single-lens reflex camera system including a quick return mirror.

(Modification 2)
The drive control executed by the second drive control unit 203b may be drive control other than so-called zoom tracking. For example, the second drive control unit 203b executes a so-called power focus in which the focus driving unit 214 drives the focus lens 210c in response to a focusing operation performed on an operation member provided on the camera body 100 or the interchangeable lens 200. You may make it do.

(Modification 3)
In response to the reception of the drive command by the lens-side first communication unit 217, the drive state transmission unit 203c may transmit drive state data related to the drive command received before the drive command to the camera body 100. . For example, when a drive command is transmitted by command data communication, if the command packet signal 402 is a drive command, the drive state transmission unit 203c sends the drive state data related to the drive command received before the drive command. It may be transmitted as the lens side data packet signal 407. The driving state data transmitted in response to the reception of the driving command is transmitted regardless of the state confirmation command. That is, when the driving command is received, the driving state transmitting unit 203c immediately transmits the driving state data relating to the immediately preceding driving command without waiting for the next reception of the state confirmation command.

  By configuring the drive state transmission unit 203c in this way, it is possible to prevent inconsistency caused by the balance between the transmission timing of the state confirmation command and the discovery timing of the in-focus position. Hereinafter, this point will be described in detail.

  FIG. 9 is a time chart of the automatic focus adjustment process. During execution of the second drive command, the body control unit 103 transmits a state confirmation command every predetermined period. When the in-focus position is found, the third drive command is transmitted at that time.

  If the slide switch 219 is operated before the transmission of the third drive command and during the transmission of the third drive command (time T22) from the transmission of the latest state confirmation command (time T21), the focus lens 210c. Changes to a position that the body control unit 103 does not assume. Therefore, the focus evaluation value calculated between time T21 and time T22 is a focus evaluation value when the focus lens 210c is located at a position not assumed by the body control unit 103, and is not a correct focus evaluation value. That is, the in-focus position found based on this incorrect focus evaluation value may also be incorrect.

  However, there is no timing for transmitting the state confirmation command after the state confirmation command is transmitted at time T21 until the third drive command is transmitted. Accordingly, the body control unit 103 drives the focus lens 210c to a focus position that may be incorrect, and determines that the automatic focus adjustment process has been normally completed.

  If the driving state transmission unit 203c transmits the previous driving command, that is, the driving state data related to the second driving command, in response to the third driving command transmitted at time T22, the body control unit 103 The driving state data is the third driving state data, and it can be known that the focus lens 210c has been driven to an unexpected position by the second driving control unit 203b between time T21 and time T22. By doing so, the accuracy of the automatic focus adjustment process is improved.

  As long as the characteristics of the present invention are not impaired, the present invention is not limited to the above-described embodiments, and other forms conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention. .

DESCRIPTION OF SYMBOLS 1 ... Camera system, 100 ... Camera body, 101 ... Body side mount part, 102, 202 ... Holding part, 103 ... Body control part, 117 ... Body side 1st communication part, 118 ... Body side 2nd communication part, 200 ... Interchangeable lens, 201 ... Lens side mount unit, 203 ... Lens control unit, 203a ... First drive control unit, 203b ... Second drive control unit, 203c ... Driving state transmission unit, 210 ... Image forming optical system, 210b ... Zoom lens , 210c ... focus lens, 212 ... zoom drive unit, 214 ... focus drive unit, 215 ... ROM, 217 ... first lens side communication unit, 218 ... second lens side communication unit

Claims (1)

An interchangeable lens that is detachably attached to the camera body,
A driving unit that drives the lens by driving force;
A receiving unit that sequentially receives a plurality of drive instruction signals indicating a drive instruction to the drive unit and a plurality of confirmation signals indicating a confirmation request for confirming an execution state of the drive instruction from the camera body;
A control unit that performs drive control of the drive unit according to the drive instruction signal received by the reception unit;
A transmission unit that transmits a state signal indicating an execution state of the corresponding drive instruction to the camera body by receiving the confirmation signal;
The plurality of drive instruction signals include an identifier for identifying each of the drive instruction signals,
The interchangeable lens in which the status signal includes the identifier included in the corresponding drive instruction signal.

Images