Interchangeable lens, camera body, camera system, and instruction method

Abstract

This interchangeable lens, which is attachable to a camera body, comprises: an optical system which includes a zoom lens movable in the optical axis direction, and of which the magnification can be changed by moving the zoom lens; a communication unit including a transmission unit that repeatedly transmits, to the camera body, a signal sequence used as a target position in a drive instruction from the camera body, and a reception unit that receives the signal sequence from the camera body as the target position of the drive instruction; and a drive unit that drives the zoom lens to the target position indicated by the signal sequence.

Description

Interchangeable lens, camera body, camera system, and instruction method

[0001] The present invention relates to an interchangeable lens, a camera body, a camera system, and an instruction method.

[0002] An accessory that can be attached to and detached from a camera body is known (for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2004-117380

[0004] According to a first aspect, the interchangeable lens is an interchangeable lens that can be attached to a camera body, and is equipped with a zoom lens that can be moved in the optical axis direction, an optical system that can change magnification by moving the zoom lens, a communication unit that includes a transmitter that repeatedly transmits to the camera body a signal sequence that is used as a target position in a drive instruction from the camera body, and a receiver that receives the signal sequence from the camera body as the target position of the drive instruction, and a drive unit that drives the zoom lens to the target position indicated by the signal sequence.

[0005] According to a second aspect, the interchangeable lens is an interchangeable lens that can be attached to a camera body, and is equipped with a zoom lens that can be moved in the optical axis direction, an optical system that can change magnification, and a communication unit that communicates with the camera body, and the communication unit transmits to the camera body first magnification information that indicates the magnification state within the magnification range of the optical system at a first granularity, and second magnification information that indicates the magnification state at a second granularity that is coarser than the first granularity, and receives the first magnification information from the camera body but does not receive the second magnification information.

[0006] According to a third aspect, the camera body is a camera body to which an interchangeable lens having a variable magnification optical system can be attached, and is equipped with a communication unit that repeatedly receives first magnification information indicating the magnification state of the optical system from the interchangeable lens, an operation unit that accepts input of a first instruction and a second instruction, and a memory unit that stores the first magnification information received from the interchangeable lens when the first instruction is input via the operation unit, and when the second instruction is input via the operation unit, the communication unit transmits the first magnification information stored in the memory unit to the interchangeable lens.

[0007] According to a fourth aspect, a camera system is a camera system comprising an accessory having a variable magnification optical system and a camera body to which the accessory can be attached, wherein the accessory comprises an accessory-side transmitter that repeatedly transmits a signal sequence indicating the magnification state of the optical system and an accessory-side receiver that receives the signal sequence as a target state in a drive instruction from the camera body, and the camera body comprises a body-side receiver that repeatedly receives the signal sequence indicating the magnification state of the optical system from the accessory and a body-side transmitter that transmits the signal sequence to the accessory as the target state for driving the optical system without changing it.

[0008] According to a fifth aspect, the instruction method is a method for instructing the state of an accessory of a camera body to which an accessory can be attached, which method repeatedly receives a signal sequence indicating the state of the accessory detected by the accessory, and transmits one of the received signal sequences as a target state in a drive instruction without modification.

[0009] The configurations of the embodiments described below may be modified as appropriate, and at least a portion of the configuration may be replaced with other components. Furthermore, components that are not particularly limited in terms of their placement may be placed in any position that can achieve their function, not limited to the placement disclosed in the embodiments.

[0010] FIG. 1 is a diagram schematically illustrating the configuration of a camera system according to an embodiment. FIG. 2 is a circuit diagram schematically illustrating electrical connections between a camera body and an interchangeable lens. FIG. 3A is an example timing chart illustrating the timing of command data communication, and FIG. 3B is an example timing chart illustrating the timing of hotline communication. FIG. 4 is a flowchart (part 1) illustrating an example of processing executed by the body-side control unit. FIG. 5 is a flowchart (part 2) illustrating an example of processing executed by the body-side control unit. FIG. 6 is a flowchart illustrating an example of processing executed by the lens-side control unit. FIG. 7A is a diagram illustrating an example of a screen displayed on the display unit. FIG. 7B is a diagram illustrating the display of an indicator when the zoom lens is at the wide-angle end. FIG. 7C is a diagram illustrating the display of an indicator when the zoom lens is at the telephoto end. FIG. 7D is a diagram illustrating the display of an indicator when the zoom lens is at neither the wide-angle end nor the telephoto end. FIG. 8 is a diagram illustrating an example of a restoration table stored in the body-side storage unit. FIG. 9 is a flowchart illustrating details of body-side initialization processing. FIG. 10 is a flowchart illustrating details of lens-side initialization processing. 11A and 11B are diagrams showing other examples of the restoration table.

[0011] A camera system 1 according to one embodiment will now be described with reference to the drawings. Fig. 1 is a diagram showing an outline of the configuration of the camera system 1. Fig. 2 is a circuit diagram showing a schematic diagram of the electrical connection between a camera body 2 and an interchangeable lens 3.

[0012] 1, the camera system 1 includes a camera body 2 and an interchangeable lens 3 that is detachable from the camera body 2. The interchangeable lens 3 is an example of an accessory.

[0013] The camera body 2 includes a body mount 21, a body terminal holder 22, a body control unit 23, a body communication unit 24, a body memory unit 25, a power supply unit 26, an image sensor 27, a display unit 28, an operation unit 29, and the like.

[0014] The body-side control unit 23 is made up of a microcomputer and its peripheral circuits, etc. The body-side control unit 23 performs various controls on the body, but the following explanation will mainly describe the portion related to position control of the zoom lens 36 a and focus lens 36 b provided in the interchangeable lens 3 when the power of the camera body 2 is turned on, and other functions will be omitted.

[0015] 2, the body side communication unit 24 includes a first body side communication unit 24a and a second body side communication unit 24b. The first body side communication unit 24a performs command and data communication (described below) with the interchangeable lens 3, and the second body side communication unit 24b performs hotline communication (described below) with the interchangeable lens 3. The first body side communication unit 24a and the second body side communication unit 24b are connected to a group of body side terminals (described below) provided in the body side terminal holding unit 22 and the body side control unit 23.

[0016] The body-side storage unit 25 is a non-volatile storage medium. The body-side storage unit 25 is connected to the body-side control unit 23. The body-side storage unit 25 stores in advance predetermined control programs and the like to be executed by the body-side control unit 23. The body-side control unit 23 controls the camera body 2 by reading the control programs from the body-side storage unit 25 and executing the programs.

[0017] The body-side storage unit 25 also stores various setting information for the camera system 1. For example, when the camera body 2 is powered on, the body-side storage unit 25 stores settings regarding whether or not to restore the states of the zoom lens 36a and the focus lens 36b to the states they had when the camera body 2 was last powered off.

[0018] The body-side storage unit 25 also stores a restoration table that stores information about the position (state) of the zoom lens 36a and information about the position (state) of the focus lens immediately before the power of the camera body 2 is turned off, in association with the identification information of the interchangeable lens 3. The restoration table will be described in detail later.

[0019] The power supply unit 26 has a power source and supplies power to the inside of the camera body 2 and the interchangeable lens 3. The power supply unit 26 is connected to a group of body side terminals (described later) provided on the body side terminal holding unit 22 and the body side control unit 23.

[0020] The image sensor 27 is a solid-state image sensor such as a CCD or CMOS. The image sensor 27 is connected to the body-side control unit 23, captures an image of a subject, and outputs an image signal. A description of the processing of the output image signal will be omitted.

[0021] The display unit 28 is a display installed on, for example, the rear surface of the camera body 2, and displays various settings for the camera system 1, through images, etc. The display unit 28 may be an electronic viewfinder.

[0022] The operation unit 29 includes various buttons such as a power button and a release button, and accepts input of various instructions to the camera system 1. If the camera body 2 is equipped with a touch panel, the touch panel may serve as the operation unit 29.

[0023] 2, the body-side terminal holding unit 22 has an LDET(B) terminal, a VBAT(B) terminal, a PGND(B) terminal, a V33(B) terminal, a GND(B) terminal, an RDY(B) terminal, a DATAB(B) terminal, a CLK(B) terminal, a DATAL(B) terminal, an HCLK(B) terminal, and an HDATA(B) terminal. These 11 body-side terminals are collectively referred to as a body-side terminal group.

[0024] The LDET(B) terminal is a terminal used to detect attachment / detachment of the interchangeable lens 3. The LDET(B) terminal is connected to the body-side control unit 23 via a resistor R2. A power supply V33 supplied from the power supply unit 26 via a resistor R1 is connected between the resistor R2 and the body-side control unit 23, and the LDET(B) terminal is pulled up.

[0025] The VBAT(B) terminal, PGND(B) terminal, V33(B) terminal, and GND(B) terminal are power supply terminals connected to the power supply unit 26. In FIG. 2 , the direction of the supplied power is indicated by an arrow. The VBAT(B) terminal is a terminal used to supply power to the interchangeable lens 3. The power supplied via the VBAT(B) terminal drives a first drive unit 37 and a second drive unit 38 of the interchangeable lens 3, which will be described later. Note that in FIG. 2 , the first drive unit 37 and the second drive unit 38 are collectively referred to as the drive unit. The operation of the first drive unit 37 and the second drive unit 38 requires a voltage and current greater than those of the lens-side control unit 33, and the voltage applied by the power supply unit 26 to the VBAT(B) terminal is approximately 10 V at most. The PGND(B) terminal is a ground terminal corresponding to the VBAT(B) terminal.

[0026] The V33(B) terminal is a terminal used to supply power to the interchangeable lens 3. The lens side control unit 33 is operated by power supplied from the power supply unit 26 via the V33(B) terminal. Each unit, such as the lens side control unit 33, operates at a lower voltage and current than the first drive unit 37 and the second drive unit 38. The voltage applied by the power supply unit 26 to the V33(B) terminal is approximately 3.3 V at maximum. The GND(B) terminal is a ground terminal corresponding to the V33(B) terminal.

[0027] The RDY(B), DATAB(B), CLK(B), and DATAL(B) terminals are connected to the body-side first communication unit 24a and are used for command and data communication, which will be described later. The HCLK(B) and HDATA(B) terminals are connected to the body-side second communication unit 24b and are used for hotline communication, which will be described later. In Figure 2, the arrows indicate the flow of signals.

[0028] The potential of the RDY(B) terminal indicates whether or not the interchangeable lens 3 is capable of command data communication. The DATAB(B) terminal is a terminal from which a data signal is output to the interchangeable lens 3. The CLK(B) terminal is a terminal from which a clock signal is output to the interchangeable lens 3. The DATAL(B) terminal is a terminal to which a data signal from the interchangeable lens 3 is input.

[0029] The HCLK(B) terminal is a terminal to which a clock signal is input from the interchangeable lens 3. The HDATA(B) terminal is a terminal to which a data signal is input from the interchangeable lens 3.

[0030] The interchangeable lens 3 includes a lens side mount 31, a lens side terminal holding unit 32, a lens side control unit 33, a lens side communication unit 34, a lens side memory unit 35, an imaging optical system 36, a first driving unit 37, and a second driving unit 38.

[0031] The lens side control unit 33 is composed of a microcomputer and its peripheral circuits, etc. As shown in Fig. 2, the lens side communication unit 34 includes a first lens side communication unit 34a and a second lens side communication unit 34b. The first lens side communication unit 34a performs command and data communication (described below) with the camera body 2, and the second lens side communication unit 34b performs hotline communication (described below) with the camera body 2. The first lens side communication unit 34a and the second lens side communication unit 34b are connected to the lens side control unit 33 and a group of lens side terminals (described below) provided in the lens side terminal holding unit 32.

[0032] The lens-side storage unit 35 is a non-volatile storage medium. The lens-side storage unit 35 is connected to the lens-side control unit 33. The lens-side storage unit 35 stores in advance predetermined control programs and the like to be executed by the lens-side control unit 33. The lens-side control unit 33 controls the interchangeable lens 3 by reading the control programs from the lens-side storage unit 35 and executing the programs.

[0033] The imaging optical system 36 forms a subject image on the imaging plane of the image sensor 27. The optical axis OA of the imaging optical system 36 substantially coincides with the center positions of the lens-side mount 31 and the body-side mount 21 (described later). The imaging optical system 36 in FIG. 1 generally includes a zoom lens 36a, a focus lens 36b, and a lens 36c. The zoom lens 36a is a lens that changes the focal length (photographic angle of view). The focus lens 36b is a lens that adjusts the imaging position of the subject image.

[0034] The first drive unit 37 is connected to the lens side control unit 33 and has an actuator (not shown) and the like. The first drive unit 37 drives the zoom lens 36a in the optical axis OA direction (+Z direction, −Z direction) using this actuator and the like. In other words, the interchangeable lens 3 according to this embodiment is a power zoom lens.

[0035] The second drive unit 38 is connected to the lens-side control unit 33 and has an actuator (not shown) and the like. The second drive unit 38 drives the focus lens 36b in the direction of the optical axis OA (+Z direction, −Z direction) using the actuator and the like. Note that although the zoom lens 36a, the focus lens 36b, and the lens 36c are each illustrated as a single lens in FIG. 1, they may each be a lens group including multiple lenses.

[0036] The lens side terminal holding unit 32 has an LDET(L) terminal, a VBAT(L) terminal, a PGND(L) terminal, a V33(L) terminal, a GND(L) terminal, an RDY(L) terminal, a DATAB(L) terminal, a CLK(L) terminal, a DATAL(L) terminal, an HCLK(L) terminal, and an HDATA(L) terminal. These 11 lens side terminals are collectively referred to as the lens side terminal group.

[0037] When the interchangeable lens 3 is attached to the camera body 2, the body-side terminals and lens-side terminals are electrically connected as shown by the dashed lines in Fig. 2. Specifically, the LDET(B) terminal is connected to the LDET(L) terminal, the VBAT(B) terminal is connected to the VBAT(L) terminal, the PGND(B) terminal is connected to the PGND(L) terminal, the V33(B) terminal is connected to the V33(L) terminal, and the GND(B) terminal is connected to the GND(L) terminal. Also, the RDY(B) terminal is connected to the RDY(L) terminal, the DATAB(B) terminal is connected to the DATAB(L) terminal, the CLK(B) terminal is connected to the CLK(L) terminal, and the DATAL(B) terminal is connected to the DATAL(L) terminal. The HCLK(B) terminal is connected to the HCLK(L) terminal, and the HDATA(B) terminal is connected to the HDATA(L) terminal. The functions of the individual lens-side terminals are the same as those of the corresponding body-side terminals, so a description thereof will be omitted.

[0038] The LDET(L) terminal is grounded via a resistor R3. When the LDET(L) terminal comes into contact with the LDET(B), the potential of the LDET(B) terminal is pulled down. The VBAT(L) terminal and the PGND(L) terminal are connected to a first drive unit 37 and a second drive unit 38. A so-called bypass capacitor C1 is connected between the VBAT(L) terminal and the PGND(L) terminal.

[0039] The V33(L) terminal and the GND(L) terminal are connected to various parts such as the lens side control unit 33. A bypass capacitor C2 is connected between the V33(L) terminal and the GND(L) terminal.

[0040] The RDY(L) terminal, DATAB(L) terminal, CLK(L) terminal, and DATAL(L) terminal are connected to the lens side first communication unit 34a, and the HCLK(L) terminal and HDATA(L) terminal are connected to the lens side second communication unit 34b.

[0041] (Command data communication) After a control command (command) from the body-side control unit 23 is sent to the lens-side control unit 33 of the interchangeable lens 3, the control content (control data) from the body-side control unit 23 and the response content (response data) from the lens-side control unit 33 are sent and received in parallel. This is called command data communication. Command data communication is full-duplex communication. This command data communication is performed by digital data communication using the RDY(B) terminal, RDY(L) terminal, DATAB(B) terminal, DATAB(L) terminal, CLK(B) terminal, CLK(L) terminal, DATAL(B) terminal, and DATAL(L) terminal via the first body-side communication unit 24a and the first lens-side communication unit 34a.

[0042] The body-side control unit 23 transmits various control commands and control details to the interchangeable lens 3 by command data communication via the body-side communication unit 24 and the lens-side communication unit 34, and transmits and receives various information to and from the interchangeable lens 3 by receiving response details from the interchangeable lens 3. The control commands referred to here are, for example, commands to transmit lens information. Examples of the various information received from the interchangeable lens 3 include model information about the interchangeable lens 3 and information indicating optical characteristics such as the focal length of the imaging optical system 36. Examples of the various information transmitted to the interchangeable lens 3 include control details such as the lens drive amount and model information about the camera body 2. Note that the control commands also include commands to drive the focus lens 36b. The lens-side control unit 33 receives various control commands from the body-side control unit 23, acquires various information from the body-side control unit 23, and transmits various information to the body-side control unit 23 by command data communication.

[0043] 3A is an example of a timing chart showing the timing of command data communication. At the start of command data communication (T1), the body-side control unit 23 first checks the signal level of the RDY (B) terminal. The signal level of the RDY (B) terminal indicates whether the lens-side control unit 33 is able to perform command data communication. If the lens-side control unit 33 is unable to perform command data communication, it sets the signal level (potential) of the RDY (L) terminal to a high level (H level). If the lens-side control unit 33 is able to perform command data communication, it sets the signal level (potential) of the RDY (L) terminal to a low level (L level) via the lens-side communication unit 34.

[0044] If the signal level of the RDY(B) terminal is low (L) at the start of command data communication (T1), the body-side control unit 23 outputs a clock signal 401 from the CLK(B) terminal via the first body-side communication unit 24a. That is, the body-side control unit 23 transmits the clock signal 401 to the lens-side control unit 33 via the CLK(B) terminal and the CLK(L) terminal. The frequency at which the clock signal 401 in FIG. 3A alternates between high and low levels is, for example, 8 MHz.

[0045] The body-side control unit 23 outputs a body-side command signal 402, which is a control command, from the DATAB(B) terminal in synchronization with the clock signal 401. That is, the body-side control unit 23 transmits the body-side command signal 402 to the lens-side control unit 33 via the DATAB(B) terminal and the DATAB(L) terminal. The body-side command signal 402, indicated by switching between high and low levels of DATAB in FIG. 3A, is a signal representing control instructions given by the body-side control unit 23 to the lens-side control unit 33 via command data communication. The body-side command signal 402 is, for example, a signal representing a request for model information about the interchangeable lens 3, a signal representing an instruction to drive the zoom lens 36a, or a signal representing an instruction to drive the focus lens 36b.

[0046] When the lens-side control unit 33 receives the body-side command signal 402 via the first lens-side communication unit 34a, it performs an inspection process to check for a communication error in the body-side command signal 402 using an error detection code (e.g., checksum data) included in the body-side command signal 402. The lens-side control unit 33 then sets the signal level of the RDY (L) terminal to high (H) (T2). If the signal level of the RDY (B) terminal is high, the body-side control unit 33 does not transmit the body-side command signal 402. The lens-side control unit 33 starts a first control process 404 based on the instructions of the received body-side command signal 402.

[0047] For example, if the received body-side command signal 402 contains content that requests specific information about the interchangeable lens 3, the lens-side control unit 33 executes, as a first control process 404, a process of generating the requested information as a lens-side data signal 407. Furthermore, if the received body-side command signal 402 is a signal that instructs driving the focus lens 36b, the lens-side control unit 33 executes, as a first control process 404, a process of generating a signal that indicates that a signal instructing driving the focus lens 36b has been received.

[0048] When the first control process 404 is completed, the lens side control unit 33 sets the signal level of the RDY(L) terminal to low level (L level) via the lens side communication unit 34 (T3). When the signal level of the RDY(B) terminal becomes low level, the body side control unit 23 outputs a clock signal 405 from the CLK(B) terminal. That is, the body side control unit 23 transmits the clock signal 405 to the lens side control unit 33 via the CLK(B) terminal and the CLK(L) terminal. Furthermore, when the signal level of the RDY(B) terminal is high level, the body side control unit 23 does not transmit or receive the body side data signal 406 or the lens side data signal 407.

[0049] The body-side control unit 23 outputs a body-side data signal 406 from the DATAB(B) terminal via the first body-side communication unit 24a in synchronization with the clock signal 405. That is, the body-side control unit 23 transmits the body-side data signal 406 to the lens-side control unit 33 via the DATAB(B) terminal and the DATAB(L) terminal. The body-side data signal 406 is a signal representing a control parameter of the body-side command signal 402. For example, if the body-side command signal 402 is a signal representing an instruction to drive the focus lens 36b, the corresponding body-side data signal 406 is a signal representing the amount of drive of the focus lens 36b. Furthermore, the body-side data signal 406 is a signal representing, for example, information required by the lens-side control unit 33 in command data communication (such as model information of the camera body).

[0050] Furthermore, when a clock signal 405 is input to the CLK(L) terminal, the lens-side control unit 33 outputs a lens-side data signal 407 from the DATAL(L) terminal in synchronization with the clock signal 405. The lens-side data signal 407, indicated by switching between high and low levels of DATA in FIG. 3A, is a signal that the lens-side control unit 33 transmits to the body-side control unit 23 via command data communication. For example, if the body-side command signal 402 is a signal requesting model information of the interchangeable lens 3, the corresponding lens-side data signal 407 is a signal representing the model information of the interchangeable lens 3. Furthermore, for example, if the received body-side command signal 402 is a signal representing an instruction to drive the focus lens 36b, the corresponding lens-side data signal 407 is a signal representing the reception of a signal representing an instruction to drive the focus lens 36b.

[0051] When the transmission of the lens-side data signal 407 is completed, the lens-side control unit 33 sets the signal level of the RDY(L) terminal to high again (T4). The lens-side control unit 33 starts a second control process 408 (described below) based on the instruction of the received body-side data signal 406. For example, if the received body-side command signal 402 is a signal indicating an instruction to drive the focus lens 36b, the lens-side control unit 33 executes, as the second control process 408, a process to drive the focus lens 36b by the drive amount specified in the body-side data signal 406.

[0052] When the second control process 408 is completed, the lens side control unit 33 sets the RDY (L) terminal to low level via the lens side communication unit 34 (T5).

[0053] The communications performed at the above-described times T1 to T5 constitute one command data communication. In one command data communication, the body side control unit 23 transmits a body side command signal 402 and a body side data signal 406. In other words, the body side command signal 402 and the body side data signal 406 together constitute one piece of control data.

[0054] As described above, the lens side control unit 33 receives control data from the body side control unit 23 and transmits response data to the body side communication unit 24 in parallel. In other words, command data communication is so-called full-duplex communication.

[0055] (Hotline communication) Another communication system is communication in which data is sent one way from the lens-side control unit 33 of the interchangeable lens 3 to the body-side control unit 23 of the camera body 2, and this is called hotline communication. Hotline communication is data communication between the body-side control unit 23 and the lens-side control unit 33 using the HCLK(B) terminal, HCLK(L) terminal, HDATA(B) terminal, and HDATA(L) terminal via the body-side second communication unit 24b and the lens-side second communication unit 34b.

[0056] The body-side control unit 23 acquires information about the state of the interchangeable lens 3 from the lens-side control unit 33 of the interchangeable lens 3 via hotline communication. Information about the state of the interchangeable lens 3 includes, for example, the position of the focus lens 36b, the position of an image stabilization lens (not shown), the position of the aperture, etc. In the following description, information about the state of the interchangeable lens 3, including, for example, the position of the focus lens 36b, the position of an image stabilization lens (not shown), the position of the aperture, etc., may be referred to as lens state information.

[0057] The image stabilization lens is a member that can be moved (driven) to include a component in a direction perpendicular to the optical axis direction, and the aperture is a member that can be moved (driven) to change the size of the opening through which the light beam passes.

[0058] Hotline communication is a communication in which, when an instruction to start communication is sent from the camera body 2 via command data communication, the lens side control unit 33 autonomously sends lens data to the body side control unit 23, regardless of (independent from) the command data communication, until an instruction to end communication is sent.

[0059] FIG. 3B is an example timing chart showing the timing of hotline communication. When the lens-side control unit 33 receives a command to start hotline communication from the body-side control unit 23 of the camera body via command data communication (T6), it performs generation processing 501. This processing acquires the status of the interchangeable lens 3 at a sampling period of, for example, 1 millisecond and generates a lens signal 503 for hotline communication. When generation of the lens signal 503 is completed (T7), the lens-side control unit 33 outputs a clock signal 502 from the HCLK(L) terminal via the second lens-side communication unit 34b. That is, the clock signal 502 is transmitted to the body-side control unit 23 via the HCLK(L) terminal and the HCLK(B) terminal. The frequency at which the clock signal 502 in FIG. 3B alternates between high and low levels is, for example, 8 MHz to 20 MHz. That is, the frequency of the clock signal 502 for hotline communication is approximately the same as or higher than the frequency of the clock signal 401 for command data communication.

[0060] The lens side control unit 33 outputs the lens signal 503 (e.g., information regarding the position of the focus lens 36b) generated in the generation process 501 from the HDATA(L) terminal via the lens side second communication unit 34b in synchronization with the clock signal 502. In other words, the lens side control unit 33 transmits the lens signal 503 to the body side control unit 23 via the lens side second communication unit 34b, the HDATA(L) terminal, the HDATA(B) terminal, and the body side second communication unit 24b.

[0061] 3B, the lens signal 503, indicated by switching between high and low levels of HDATA, is a signal that the lens side control unit 33 transmits to the body side control unit 23 via hotline communication. The output of the clock signal 502 and lens signal 503 ends at timing T8. The lens side control unit 33 repeats transmitting lens data via hotline communication at regular intervals (e.g., every 1 millisecond) until it receives an instruction to stop transmitting the lens signal 503 via command data communication.

[0062] Command data communication and hotline communication can be performed in part or in whole in parallel. That is, the body-side control unit 23 and the lens-side control unit 33 can start or end hotline communication while command data communication is being performed. Also, command data communication can be started or ended while hotline communication is being performed.

[0063] As explained above, hotline communication is carried out independently of command data communication. The lens-side control unit 33 transmits information regarding the state of the interchangeable lens 3 to the body-side control unit 23 via hotline communication, regardless of command data communication. This allows the body-side control unit 23 to continuously monitor the state of the interchangeable lens 3 even during command data communication. This allows the body-side control unit 23 to continuously monitor the position of the focus lens 36b, enabling high-speed autofocus control, for example. The same applies to image stabilization control and aperture control.

[0064] Furthermore, the body-side control unit 23 can issue various instructions to the interchangeable lens 3 at any timing through command data communication, even while the lens-side control unit 33 is performing hotline communication.

[0065] As described above, the interchangeable lens 3 according to this embodiment is a power zoom lens in which the first drive unit 37 drives the zoom lens 36a in the optical axis OA direction to change the focal length (photographic angle of view). In the case of a manual zoom lens, if the zoom operation ring is not operated after the camera body 2 is powered off until the next time the camera body 2 is powered on, the zoom lens position remains the same as when the power was turned off. In contrast, in a conventional power zoom lens, when the camera body 2 is powered on after being powered off, an origin detection process is executed to move the zoom lens position to the origin position, so the zoom lens position is not the same as when the power was turned off. For this reason, some users may find power zoom lenses to be less convenient.

[0066] In the camera system 1 of this embodiment, when the power to the camera body 2 is turned off and then turned on again, the state of the zoom lens 36a and the state of the focus lens 36b can be restored to the state they were in when the power to the camera body 2 was turned off.

[0067] The processing executed by the camera system 1 to realize the above functions will be described with reference to the flowcharts of Figures 4 to 6. Figures 4 and 5 are flowcharts showing an example of processing executed by the body-side control unit 23, and Figure 6 is a flowchart showing an example of processing executed by the lens-side control unit 33.

[0068] The processes in Figures 4 and 5 begin when the camera body 2 is powered on. In the process in Figure 4, the body-side control unit 23 first determines whether the interchangeable lens 3 is attached to the camera body 2 (step SB11). When the interchangeable lens 3 is not attached to the camera body 2, the signal level of the LDET(B) terminal is pulled up and is at a high level. When the body-side control unit 23 detects that the signal level of the LDET(B) terminal is at a high level, it determines that the interchangeable lens 3 is not attached to the camera body 2 (step SB11 / NO). When the interchangeable lens 3 is not attached, the body-side control unit 23 does not supply power to the VBAT(B) terminal and V33(B) terminal from the power supply unit 26.

[0069] When the interchangeable lens 3 is attached to the camera body 2, the signal level of the LDET(B) terminal is pulled down to low. If the signal level of the LDET(B) terminal is low, the body-side control unit 23 determines that the interchangeable lens 3 is attached. If the interchangeable lens 3 is attached to the camera body 2 (step SB11 / YES), the body-side control unit 23 causes the power supply unit 26 to start supplying power to the V33(B) terminal (step SB13).

[0070] When power supply to the V33(B) terminal starts, power is supplied to the lens-side control unit 33 of the interchangeable lens 3 via the V33(L) terminal, and the lens-side control unit 33 starts operating. As a result, the lens-side control unit 33 starts the processing shown in FIG.

[0071] After starting operation, the lens-side control unit 33 permits initial communication with the body-side control unit 23 via command and data communication. After the lens-side control unit 33 permits initial communication, the body-side control unit 23 starts initial communication. The initial communication includes a signal requesting the lens-side control unit 33 to supply power to the VBAT(L) terminal. When the signal requesting power supply to the VBAT(L) terminal is sent from the lens-side control unit 33 to the body-side control unit 23, the body-side control unit 23 supplies power to the VBAT(B) terminal, and initialization processing ( FIG. 4 : step SB15, FIG. 6 : step SL11) is performed between the camera body 2 and the interchangeable lens 3. During the initialization processing, information required for various operations of the camera system 1, such as shooting operations and focus adjustment operations, is exchanged between the camera body 2 and the interchangeable lens 3, and the zoom lens 36 a and focus lens 36 b of the interchangeable lens 3 are moved to their positions before power was turned off or to their default positions. The body-side initialization process (step SB15) executed by the body-side control unit 23 and the lens-side initialization process (step SL11) executed by the lens-side control unit 33 will be described in detail below.

[0072] When the initialization process (step SB15) is completed, the body-side control unit 23 requests the lens-side control unit 33 to start hotline communication ( FIG. 4 : step SB17). Specifically, the body-side control unit 23 transmits a command to start hotline communication to the lens-side control unit 33 by command data communication.

[0073] On the other hand, when the initialization process (step SL11) is completed, the lens side control unit 33 executes the processes of steps SL13 to SL16 in FIG. 6 and the processes of steps SL17 and SL19 in FIG. 6 in parallel.

[0074] First, the processing of steps SL13 to SL16 in Fig. 6 will be described. The lens side control unit 33 waits until it receives a request to start hotline communication (step SL13 / NO). When it receives the request to start hotline communication (step SL13 / YES), the lens side control unit 33 starts hotline communication and transmits lens state information, including information about the position of the focus lens 36b (step SL14).

[0075] Next, the lens-side control unit 33 determines whether a predetermined time has elapsed since executing the processing of step SL14 (step SL15). If the predetermined time has elapsed since executing the processing of step SL14 (step SL15 / YES), the lens-side control unit 33 returns to step SL14 and transmits the lens status information again via hotline communication (step SL14).

[0076] If a predetermined time has not elapsed since the processing of step SL14 was executed (step SL15 / NO), the lens side control unit 33 determines whether or not a request to end hotline communication has been received from the body side control unit 23 (step SL16).

[0077] If a request to end the hotline communication is received (step SL16 / YES), the process returns to step SL13. If a request to end the hotline communication is not received (step SL16 / NO), the process returns to step SL15. As a result, lens state information including information about the position of the focus lens 36b is transmitted to the body-side control unit 23 at a predetermined interval until a request to end the hotline communication is received.

[0078] Returning to FIG. 4, after requesting the start of hotline communication (step SB17), the body-side control unit 23 executes the processes of steps SB19 and SB21 and the processes of steps SB23 to SB29 in parallel.

[0079] First, the processing of steps SB19 and SB21 will be described. The body-side control unit 23 determines whether lens status information has been received (step SB19). If lens status information has been received (step SB19 / YES), information about the position of the focus lens 36b included in the lens status information (hereinafter referred to as in-focus position information) is stored in a volatile memory (e.g., RAM (Random-Access Memory)) (not shown) provided in the body-side control unit 23 (step SB21). The information about the position of the focus lens 36b is, for example, information indicating shooting distance information based on the position of the focus lens 36b. Note that the information about the position of the focus lens 36b may be any information that allows the body-side control unit 23 to recognize shooting distance information. Note that the body-side control unit 23 may also store information other than the in-focus position information included in the lens status information in the volatile memory.

[0080] If the lens state information has not been received (step SB19 / NO), the process of step SB21 is skipped.

[0081] Furthermore, in parallel with the processing of steps SB19 and SB21, the body-side control unit 23 requests the lens-side control unit 33 to transmit batch transmission information (step SB23). The request for batch transmission information by the body-side control unit 23 is repeated at regular intervals. However, the body-side control unit 23 can interrupt the repeated requests for batch transmission information to execute command data communication such as driving instructions to the interchangeable lens 3 or requests for information not included in the batch transmission information.

[0082] In this embodiment, the batch transmission information includes information for restoring the state (position) of the zoom lens 36a when the camera body 2 is powered on to the state (position) it was in when the camera body 2 was last powered off (hereinafter referred to as zoom lens drive position information (first magnification information)), control focal length information (third magnification information) used to display an indicator showing the focal length on the display unit 28, and display focal length information (second magnification information) used to display the focal length value on the display unit 28.

[0083] The zoom lens drive position information is information that indicates the magnification state of the imaging optical system 36, and includes, for example, a value indicating the current position of the zoom lens 36a (hereinafter referred to as the position indication value), and the direction in which the zoom lens 36a was moving or is currently moving when the zoom lens 36a stopped at the current position (hereinafter referred to as the movement direction).

[0084] The position indication value of the zoom lens 36a is a value that depends on the model of the interchangeable lens 3, etc. For example, the position indication value of the zoom lens 36a can be a position of the zoom lens 36a (an integer from 0 to 100) expressed by dividing the magnification range of the imaging optical system 36 into 100, with the wide-angle end being 0 and the telephoto end being 100. Furthermore, for example, if the first drive unit 37 includes a stepping motor as an actuator, the position indication value of the zoom lens 36a may be the number of steps from the origin position of the stepping motor. Furthermore, for example, if the first drive unit 37 includes an ultrasonic motor or a voice coil motor as an actuator, the position indication value of the zoom lens 36a may be an absolute position of the zoom lens 36a detected by an encoder or the like. Furthermore, for example, if the zoom lens 36a includes multiple lenses, and the multiple lenses are connected to a cam barrel and the focal length is changed by rotating the cam barrel to drive the multiple lenses in conjunction with each other, the position indication value of the zoom lens 36a may be a value that indicates, for example, the rotational position of the cam barrel.

[0085] The direction of movement indicates, for example, whether the zoom lens 36a stops when the imaging optical system 36 is changing from a telephoto state to a wide-angle state, i.e., when the zoom lens 36a is moving in the +Z direction, or whether the zoom lens 36a stops when the imaging optical system 36 is changing from a wide-angle state to a telephoto state, i.e., when the zoom lens 36a is moving in the -Z direction.

[0086] The control focal length information is, for example, information indicating the focal length (mm) calculated from the position of the zoom lens 36a (an integer from 0 to 100) in which the magnification range of the imaging optical system 36 is divided into 100 parts, with the wide end being 0 and the telephoto end being 100.

[0087] The display focal length information indicates a focal length (mm) calculated from the position of the zoom lens 36a (an integer between 0 and 50) by dividing the magnification range of the imaging optical system 36 by a smaller number (for example, 50) than the number of divisions used in the control focal length information, with the wide-angle end being 0 and the telephoto end being 50. Therefore, the focal length indicated by the control focal length information is more precise than the focal length indicated by the display focal length information. Note that the position indication values ​​included in the zoom lens driving position information are also more precise than the values ​​indicating the position of the zoom lens 36a used to calculate the display focal length information. The position indication values ​​included in the zoom lens driving position information are either as precise or more precise than the position of the zoom lens 36a used to calculate the control focal length information.

[0088] Meanwhile, in parallel with the processing of steps SL13 to SL16, the lens-side control unit 33 determines whether or not a request to send batch transmission information has been received ( FIG. 6 : step SL17). If a request to send batch transmission information has been received (step SL17 / YES), the lens-side control unit 33 generates the batch transmission information and sends the generated batch transmission information to the body-side control unit 23 by command data communication (step SL19). If a request to send batch transmission information has not been received (step SL17 / NO), the lens-side control unit 33 skips the processing of step SL19.

[0089] Meanwhile, after requesting the transmission of the batch transmission information, the body-side control unit 23 waits until it receives the batch transmission information (FIG. 4: step SB25 / NO). Then, upon receiving the batch transmission information (step SB25 / YES), the body-side control unit 23 stores the batch transmission information in volatile memory (not shown) (step SB27). At this time, the body-side control unit 23 stores the zoom lens drive position information included in the batch transmission information in volatile memory as is without processing the information.

[0090] Next, the body-side control unit 23 updates the display content of the display unit 28 based on the display focal length information and control focal length information included in the batch transmission information (step SB29).

[0091] Fig. 7A is a diagram showing an example of a screen displayed on the display unit 28. As shown in Fig. 7A, in this embodiment, the display unit 28 displays a focal length value 281 and an indicator 282 indicating the focal length.

[0092] The focal length value 281 is displayed based on the display focal length information. For example, the focal length indicated by the display focal length information is displayed as the focal length value 281. Note that the body-side control unit 23 has acquired information indicating the magnification (zoom) range (focal length range) of the imaging optical system 36 through initial communication with the lens-side control unit 33.

[0093] The indicator 282 is displayed based on the control focal length information and indicates the current position (focal length) within the magnification range (focal length range) of the imaging optical system 36.

[0094] The telephoto end 282a of the indicator 282 indicates the position of the zoom lens 36a (the focal length of the imaging optical system 36). In this embodiment, when the zoom lens 36a is not at the wide-angle end or the telephoto end, the indicator 282 is displayed so that the focal length indicated by the end 282a of the indicator 282 is smaller than the actual focal length. In other words, the smaller the angle of view, the longer the indicator 282 becomes, but the rate at which the length of the indicator 282 changes with respect to the angle of view differs between the end points (wide-angle end, telephoto end) and the remaining portions. This point will be explained.

[0095] 7B is a diagram showing the display of the indicator 282 when the zoom lens 36a is at the wide end. The position of the end 282a of the indicator 282 changes, for example, in increments of 1 from 0 to 100. 0 indicates the wide end, and 100 indicates the telephoto end. When the zoom lens 36a is at the wide end, the position of the end 282a of the indicator 282 is 0.

[0096] 7C is a diagram showing the display of the indicator 282 when the zoom lens 36a is at the telephoto end. When the zoom lens 36a is at the telephoto end, the position of the end 282a of the indicator 282 is 100.

[0097] 7D is a diagram showing the display of the indicator 282 when the zoom lens 36a is not at either the wide-angle or telephoto end. For example, suppose the control focal length, converted into an integer value between 0 and 100, is 98. In this case, in this embodiment, the position of the end 282a of the indicator 282 is set to a value smaller than 98 (e.g., 96). This emphasizes whether the state of the zoom lens 36a will change due to zooming, making it easier for the user to grasp the state of the zoom lens 36a. The formula for calculating the position of the end 282a of the indicator 282 based on the control focal length information can be set as appropriate.

[0098] When the zoom lens 36a reaches the telephoto end or the wide-angle end, the color of the indicator 282 may be changed, or the fact that the zoom lens 36a has reached the telephoto end or the wide-angle end may be displayed using an icon, text, or the like, to emphasize that the zoom lens 36a has reached the telephoto end or the wide-angle end. Highlighting that the zoom lens 36a has reached the telephoto end or the wide-angle end, or whether the state of the zoom lens 36a will change as a result of zooming, is more effective when zooming is performed using an operating member whose operating state does not change even when the zoom lens 36a reaches the telephoto end or the wide-angle end, such as a zoom operation ring, zoom lever, or button.

[0099] 4, the body-side control unit 23 determines whether or not it has received an instruction to power off the camera body 2 (power-off instruction) (step SB31). For example, the body-side control unit 23 determines that it has received a power-off instruction when the power button (operation unit 29) is pressed.

[0100] If a power-off command has not been received (step SB31 / NO), the body-side control unit 23 executes steps SB19 and SB21 and steps SB23 to SB29 in parallel. That is, steps SB19 and SB21 and steps SB23 to SB29 are repeatedly executed until a power-off command is received.

[0101] When a power-off operation is received from the user (step SB31 / YES), the body-side control unit 23 determines whether or not to store the zoom lens drive position information ( FIG. 5 : step SB33). Whether or not to store the zoom lens drive position information is set in advance by the user. Specifically, if the camera body 2 is set to restore the state of the zoom lens 36a when the camera body 2 is last powered off when the camera body 2 is powered on, the body-side control unit 23 determines to store the zoom lens drive position information.

[0102] If the zoom lens drive position information is to be stored (step SB33 / YES), the body-side control unit 23 stores the zoom lens drive position information stored in a volatile memory (not shown) in the zoom lens drive position information field of the restoration table stored in the non-volatile body-side storage unit 25 (step SB35). The restoration table will now be described in detail.

[0103] Fig. 8 shows an example of a restoration table stored in the body-side storage unit 25. As described above, the restoration table stores information about the state (position) of the zoom lens 36a and information about the state (position) of the focus lens 36b immediately before the power to the camera body 2 was turned off, in association with the identification information of the interchangeable lens 3. As shown in Fig. 8, the restoration table includes items for interchangeable lens identification information, focus lens position information, and zoom lens drive position information.

[0104] The field for interchangeable lens identification information stores information for identifying the interchangeable lens 3 currently attached to the camera body 2. The information for identifying the interchangeable lens 3 is, for example, data indicating the model name of the interchangeable lens 3. The field for zoom lens drive position information stores the zoom lens drive position information stored in the volatile memory in step SB27 as is (without processing). This is because the content and format of the zoom lens drive position information differ depending on the interchangeable lens 3.

[0105] The field for focus lens position information stores in-focus position information received through hotline communication and stored in nonvolatile memory.

[0106] If the zoom lens drive position information is not to be stored (step SB33 / NO), the body-side control unit 23 stores a value (e.g., a NULL value) indicating that the state of the zoom lens 36a will not be restored in the zoom lens drive position information field of the restoration table (step SB36). Note that the body-side control unit 23 may store, for example, information indicating a default position in the zoom lens drive position information field of the restoration table, or may store information instructing movement to the default position, or may not store a value in the zoom lens drive position information field. In other words, if it is determined that the state of the zoom lens 36a will not be restored, the data stored in the zoom lens drive position information field is not limited to that of this embodiment.

[0107] After step SB35 or SB36, the body-side control unit 23 determines whether to store the focus lens position information (step SB37). Whether to store the focus lens position information is set in advance by the user. Specifically, if the camera body 2 is set to restore the state of the focus lens 36b when the camera body 2 is last powered off when the camera body 2 is powered on, the body-side control unit 23 determines to store the focus lens position information.

[0108] If the focus lens position information is to be stored (step SB37 / YES), the body side control unit 23 stores the in-focus position information stored in the volatile memory in the focus lens position information field of the restoration table (step SB39).

[0109] If the focus lens position information is not to be stored (step SB37 / NO), the body-side control unit 23 stores a value (e.g., a NULL value) indicating that the state of the focus lens 36b will not be restored in the focus lens position information field of the restoration table (step SB40). Note that the body-side control unit 23 may store, for example, information indicating a default position in the focus lens position information field of the restoration table, or may store information instructing movement to the default position, or may not store a value in the focus lens position information field. In other words, if it is determined that the state of the focus lens 36b will not be restored, the data stored in the focus lens position information field is not limited to that of this embodiment.

[0110] Thus, in this embodiment, when storing zoom lens drive position information and focus lens position information, the body side control unit 23 stores in the restoration table the focus position information and zoom lens drive position information that were last transmitted from the interchangeable lens 3 out of the focus position information and zoom lens drive position information that were repeatedly transmitted from the interchangeable lens 3 before the power-off instruction was input.

[0111] After step SB39 or SB40, the body-side control unit 23 executes processing to turn off the power (power-off processing) (step SB41), and ends the processing in Figures 4 and 5. For example, the body-side control unit 23 transmits to the lens-side control unit 33 a request to execute processing necessary to turn off the power (power-off processing) or a notification to end the power supply to the interchangeable lens 3, and when the lens-side control unit 33 receives a signal indicating that the processing necessary to turn off the power has been completed, the body-side control unit 23 ends the power supply to the interchangeable lens 3.

[0112] Meanwhile, the lens-side control unit 33 determines whether the power of the camera body 2 is to be turned off ( FIG. 6 : step SL21). When the lens-side control unit 33 receives a request to execute a power-off process or a notification that power supply has ended from the body-side control unit 23, for example, by command data communication, the lens-side control unit 33 determines that the power of the camera body 2 is to be turned off.

[0113] If the power supply to the camera body 2 is not turned off (step SL21 / NO), the process returns to step SL17.

[0114] If the camera body 2 is to be powered off (step SL21 / YES), the lens side control unit 33 executes the processing required to turn off the power (power-off processing) (step SL23), and ends the processing in Fig. 6. Note that during the power-off processing, the execution of steps SL13 to SL16 is completed.

[0115] Through the above processing, the next time the power to the camera body 2 is turned on, information is acquired for restoring the state of the zoom lens 36a and the state of the focus lens 36b to the state when the power was turned off.

[0116] Next, the body-side initialization process (step SB15) and the lens-side initialization process (step SL11) will be described. Fig. 9 is a flowchart showing the details of the body-side initialization process (step SB15), and Fig. 10 is a flowchart showing the details of the lens-side initialization process (step SL11).

[0117] In the lens-side initialization process (step SL11) shown in FIG. 10, the lens-side control unit 33 transmits information for identifying the interchangeable lens 3 (interchangeable lens identification information) by command data communication (step SL111).

[0118] Meanwhile, the body-side control unit 23 waits until it receives information for identifying the interchangeable lens 3 (FIG. 9: step SB151 / NO). Upon receiving the information for identifying the interchangeable lens 3 (step SB151 / YES), the body-side control unit 23 determines whether the received information for identifying the interchangeable lens 3 matches the interchangeable lens identification information stored in the restoration table stored in the body-side storage unit 25 (step SB152).

[0119] If the received identification information of the interchangeable lens 3 does not match the interchangeable lens identification information stored in the restoration table stored in the body-side storage unit 25 (step SB152 / NO), the body-side control unit 23 resets the restoration table (step SB153). If the received identification information of the interchangeable lens 3 does not match the interchangeable lens identification information stored in the restoration table stored in the body-side storage unit 25, this means that the interchangeable lens 3 attached to the camera body 2 the last time the camera was powered off is different from the interchangeable lens 3 currently attached to the camera body 2. In this case, even if the information stored in the restoration table is used, it is not possible to restore the states of the zoom lens 36a and focus lens 36b at the time the camera was powered off. Therefore, the body-side control unit 23 resets the restoration table. After resetting the restoration table, the body-side control unit 23 stores the identification information of the interchangeable lens 3 received in step SB151 in the interchangeable lens identification information field of the restoration table.

[0120] On the other hand, if the received identification information of the interchangeable lens 3 matches the interchangeable lens identification information stored in the restoration table stored in the body-side storage unit 25 (step SB152 / YES), the body-side control unit 23 transmits initialization processing information corresponding to the information stored in the restoration table to the lens-side control unit 33 (step SB154). The initialization processing information includes various information used in the initialization processing of the interchangeable lens 3.

[0121] Specifically, if focus lens position information and zoom lens drive position information are stored in the restoration table, the body-side control unit 23 transmits a signal indicating that the initialization processing information includes focus lens position information and zoom lens drive position information as the body-side command signal 402. In this case, the body-side control unit 23 transmits initialization processing information including focus lens position information and zoom lens drive position information to the lens-side control unit 33 as the body-side data signal 406. Furthermore, if focus lens position information is stored in the restoration table but the zoom lens drive position information is a NULL value, the body-side control unit 23 transmits a signal indicating that the initialization processing information includes focus lens position information but does not include zoom lens drive position information as the body-side command signal 402. In this case, the body-side control unit 23 transmits initialization processing information including focus lens position information but not zoom lens drive position information to the lens-side control unit 33 as the body-side data signal 406. Furthermore, if focus lens position information is a NULL value and zoom lens drive position information is stored in the restoration table, the body-side control unit 23 transmits the initialization processing information including zoom lens drive position information but not focus lens position information as the body-side command signal 402. In this case, the body-side control unit 23 transmits initialization processing information that does not include focus lens position information but does include zoom lens drive position information to the lens-side control unit 33 as a body-side data signal 406. Furthermore, if both the focus lens position information and the zoom lens drive position information are NULL values ​​in the restoration table, the body-side control unit 23 transmits a body-side command signal 402 indicating that the initialization processing information does not include either focus lens position information or zoom lens drive position information. In this case, initialization processing information that does not include either focus lens position information or zoom lens drive position information is transmitted to the lens-side control unit 33 as a body-side data signal 406. If the restoration table is reset in step SB153, the body-side control unit 23 executes the same processing as when both the focus lens position information and the zoom lens drive position information are NULL values ​​in the restoration table.

[0122] The zoom lens drive position information included in the initialization processing information is the data itself (data that has not been processed by the body-side control unit 23) received from the interchangeable lens 3. This is because, as described above, the data content and format included in the zoom lens drive position information differ depending on the model of the interchangeable lens 3, etc.

[0123] After transmitting the initialization processing information, the body side control unit 23 executes other necessary initialization processing (step SB155) and ends the processing of FIG.

[0124] 10, the lens-side control unit 33 receives initialization processing information from the body-side control unit 23 (step SL112). Next, the lens-side control unit 33 determines whether zoom lens drive position information has been received (step SL113). If the initialization processing information includes zoom lens drive position information, the lens-side control unit 33 can determine that zoom lens drive position information has been received.

[0125] If the lens-side control unit 33 has received the zoom lens drive position information (YES in step SL113), the lens-side control unit 33 drives the zoom lens 36a based on the zoom lens drive position information, and restores the state (position) of the zoom lens 36a to the state (position) when the power was turned off (step SL114). In other words, the zoom lens drive position information is information that indicates the target position in the drive command for the zoom lens 36a.

[0126] For example, suppose the zoom lens drive position information includes a position indication value and a movement direction of the zoom lens 36a. The position indication value is expressed as 40 when the magnification range of the imaging optical system 36 is divided into 100, with the wide end being 0 and the telephoto end being 100, and the movement direction of the zoom lens 36a is the +Z direction. In this case, the lens-side control unit 33 drives the zoom lens 36a to a position of 50, for example, and then drives it to a position of 40. Also, suppose the position indication value of the zoom lens 36a is expressed as 40 and the movement direction is the −Z direction. In this case, the zoom lens 36a is driven to a position of 30, for example, and then drives it to a position of 40. Because backlash or the like can occur depending on the drive direction, the state (position) of the zoom lens 36a at the time of power off can be restored with high accuracy by driving the zoom lens 36a while taking into consideration the direction in which the zoom lens 36a was moving when it stopped.

[0127] If the zoom lens drive position information has not been received (step SL113 / NO), the lens-side control unit 33 drives the zoom lens 36a to a predetermined position (default position) (step SL115). The default position may be stored in advance in the lens-side storage unit 35, for example.

[0128] Next, the lens-side control unit 33 determines whether or not focus lens position information has been received (step SL116). If the initialization processing information includes focus lens position information, the lens-side control unit 33 can determine that focus lens position information has been received.

[0129] If focus lens position information has been received (step SL116 / YES), the lens-side control unit 33 drives the focus lens 36b based on the focus lens position information and restores the state (position) of the focus lens 36b to the state (position) when the power was turned off (step SL117). On the other hand, if focus lens position information has not been received (step SL116 / NO), the lens-side control unit 33 drives the focus lens 36b to a predetermined position (default position) (step SL118). The default position may be stored in advance in the lens-side storage unit 35, for example.

[0130] Thereafter, the lens side control unit 33 executes other necessary initialization processes (step SL119) and returns to the process of FIG.

[0131] As described above in detail, the interchangeable lens 3 according to this embodiment is an interchangeable lens 3 that can be attached to the camera body 2, and includes an imaging optical system 36 that is equipped with a zoom lens 36a that is movable in the optical axis OA direction and whose magnification can be changed by moving the zoom lens 36a, a lens-side communication unit 34 that repeatedly transmits zoom lens drive position information used as a target position in a drive instruction for the imaging optical system 36 to the camera body 2 and receives the zoom lens drive position information from the camera body 2 as the target position of the drive instruction, and a first drive unit 37 that drives the zoom lens 36a to the target position indicated by the zoom lens drive position information. This makes it possible to restore the state of the zoom lens 36a indicated by the zoom lens drive position information received from the camera body 2 in the interchangeable lens 3.

[0132] Furthermore, in this embodiment, the zoom lens drive position information indicates the position (magnification state) of the zoom lens 36a within the magnification range of the imaging optical system 36 at a first granularity (e.g., an integer value between 0 and 100), and the lens side communication unit 34 repeatedly transmits to the camera body 2 display focal length information indicating the magnification state (focal length) within the magnification range of the imaging optical system 36 at a second granularity coarser than the first granularity (e.g., a focal length based on an integer value between 0 and 50), as well as the zoom lens drive position information. The lens side communication unit 34 receives the zoom lens drive position information from the camera body 2 but does not receive the display focal length information. The position (focal length) of the zoom lens 36a indicated by the display focal length information is a coarser value than the position of the zoom lens 36a indicated by the zoom lens drive position information. By driving the zoom lens 36a based on the position of the zoom lens 36a indicated at a more granularity, the state indicated by the zoom lens drive position information can be restored with high accuracy.

[0133] Furthermore, in this embodiment, when power supply from the camera body 2 begins, the lens side communication unit 34 transmits identification information for identifying the interchangeable lens 3 to the camera body 2, and receives zoom lens drive position information after transmitting the identification information. This makes it possible to prevent the reception of zoom lens drive position information for an interchangeable lens other than the interchangeable lens 3.

[0134] In this embodiment, the imaging optical system 36 includes a focus lens 36b that can change the focus position of the imaging optical system 36 by moving in the direction of the optical axis OA, and the lens side communication unit 34 includes a first lens side communication unit 34a that communicates with the camera body 2 and a second lens side communication unit 34b that communicates with the camera body 2 independently of the first lens side communication unit 34a. Focus position information indicating the position of the focus lens 36b is transmitted to the camera body 2 by the second lens side communication unit 34b and received from the camera body 2 by the first lens side communication unit 34a, and zoom lens drive position information is transmitted to the camera body 2 by the first lens side communication unit 34a and received from the camera body 2 by the first lens side communication unit 34a. As a result, by storing the focus position information in the restoration table, the position of the focus lens 36b can be restored to the state indicated by the focus position information.

[0135] Furthermore, in this embodiment, the zoom lens drive position information includes information (movement direction) indicating whether the imaging optical system 36 changed from a wide-angle state to a telephoto state or from a telephoto state to a wide-angle state when the state of the zoom lens 36a became the state indicated by the zoom lens drive position information. As a result, when restoring the state indicated by the zoom lens drive position information, the direction in which the zoom lens 36a is driven and stopped is set to the direction indicated by the zoom lens drive position information, so that the state of the zoom lens 36a can be more accurately restored to the state indicated by the zoom lens drive position information.

[0136] Furthermore, the camera body 2 according to this embodiment is a camera body 2 to which an interchangeable lens 3 equipped with a variable magnification imaging optical system 36 can be attached, and is equipped with a body-side communication unit 24 that repeatedly receives zoom lens drive position information indicating the state of magnification of the imaging optical system 36 from the interchangeable lens 3, an operation unit 29 that accepts power-off instructions and power-on instructions, and a body-side memory unit 25 that stores the zoom lens drive position information received from the interchangeable lens 3 when a power-off instruction is input via the operation unit 29, and when a power-on instruction is input via the operation unit 29, the body-side communication unit 24 transmits the zoom lens drive position information stored in the body-side memory unit 25 to the interchangeable lens 3. This allows the interchangeable lens 3 to restore the state of the zoom lens 36a indicated by the zoom lens drive position information stored in the body-side memory unit 25.

[0137] Furthermore, the camera system 1 according to this embodiment includes an interchangeable lens 3 equipped with a variable magnification imaging optical system 36, and a camera body 2 to which the interchangeable lens 3 can be attached. The interchangeable lens 3 is equipped with a lens-side communication unit 34 that repeatedly transmits a signal sequence (zoom lens drive position information) indicating the state of magnification of the imaging optical system 36 and receives the signal sequence as a target state in a drive instruction from the camera body 2. The camera body 2 is equipped with a body-side communication unit 24 that repeatedly receives a signal sequence (zoom lens drive position information) indicating the state of magnification of the imaging optical system 36 from the interchangeable lens 3 and transmits the signal sequence to the interchangeable lens 3 without changing it as a target state for driving the imaging optical system 36. Because the camera body 2 transmits the signal sequence received from the interchangeable lens 3 to the interchangeable lens 3 without changing it as the target state for driving the imaging optical system 36, the state of magnification of the imaging optical system 36 of the interchangeable lens 3 can be set to the target state indicated by the signal sequence regardless of the model of the interchangeable lens 3.

[0138] In the above embodiment, the restoration table is reset when the interchangeable lens 3 attached to the camera body 2 when the power is turned off is different from the interchangeable lens 3 attached to the camera body 2 when the power is turned on. However, this is not limited to this. As shown in FIG. 11A , the restoration table stores focus lens position information and zoom lens drive position information for each of multiple interchangeable lenses 3 of different models in association with each other. If the identification information of the interchangeable lens 3 attached to the camera body 2 when the power is turned on is registered in the restoration table, the states of the zoom lens 36 a and the focus lens 36 b can be restored to the states indicated by the information in the restoration table. Furthermore, if the identification information of the interchangeable lens 3 attached to the camera body 2 when the power is turned on is not registered in the restoration table, a new record can be added to the restoration table. This allows the state of each interchangeable lens 3 when the power is turned off to be restored when the power is turned on in a camera body 2 to which multiple interchangeable lenses 3 can be attached.

[0139] 11B , when the identification information of multiple interchangeable lenses 3 is stored in the restoration table, the serial number of the interchangeable lens 3 may be stored as the interchangeable lens identification information in addition to model information of the interchangeable lens 3. This allows, for example, even if a camera body 2 is shared by multiple users each having interchangeable lenses 3 of the same model but with different serial numbers, when each user uses the camera body 2 with their own interchangeable lens 3 attached, to restore the state of the interchangeable lens 3 from the last time the camera body 2 was powered off.

[0140] In the above embodiment, the zoom lens drive position information and focus lens position information are stored in the restoration table when the power is turned off, but the states of the zoom lens 36 a and focus lens 36 b may be stored in the restoration table when, for example, a predetermined operation unit 29 (such as a button) is operated or when an instruction is received from the user even while the camera system 1 is in use. Furthermore, each time an instruction is received, multiple states of the zoom lens 36 a and focus lens 36 b may be stored in the restoration table in association with the instruction.

[0141] Furthermore, in the above embodiment, when the power is turned on, the states of the zoom lens 36a and the focus lens 36b are restored to the state indicated by the information stored in the restoration table. However, even when the camera system 1 is in use, for example, when a predetermined operation unit 29 (button, etc.) is operated or when an instruction is received from the user, the states of the zoom lens 36a and the focus lens 36b may be restored to the state indicated by the information stored in the restoration table.

[0142] Furthermore, in the above embodiment, the restoration table is stored in the body-side storage unit 25, but it may also be stored in the lens-side storage unit 35. In this case, when an instruction (storage instruction) to store zoom lens drive position information and focus lens position information is input, the body-side control unit 23 simply transmits information indicating that the storage instruction has been input to the interchangeable lens 3. The lens-side control unit 33 of the interchangeable lens 3 simply stores the states of the zoom lens 36 a and the focus lens 36 b at the time of receiving the information indicating that the storage instruction has been input in the lens-side storage unit 35. When an instruction (restoration instruction) to restore the zoom lens 36 a and the focus lens 36 b to the positions stored in the restoration table is input, the body-side control unit 23 simply transmits information indicating that the restoration instruction has been input to the interchangeable lens. Furthermore, the storage instruction and restoration instruction may be input to the interchangeable lens 3 by the user.

[0143] Furthermore, in the above embodiment, when storing zoom lens drive position information and focus lens position information, the body-side control unit 23 stores in the restoration table the focus position information and zoom lens drive position information last transmitted from the interchangeable lens 3 out of the focus position information and zoom lens drive position information repeatedly transmitted from the interchangeable lens 3 before the power-off instruction was input. However, this is not limited to this. When the power-off instruction is input, the body-side control unit 23 may request the interchangeable lens 3 to transmit batch transmission information, and store the zoom lens drive position information included in the batch transmission information transmitted in response to the request in the restoration table. Furthermore, the body-side control unit 23 may store in the restoration table the focus lens position information included in the lens state information received after the power-off instruction was input.

[0144] In addition, in the above embodiment, if lens 36c is also a zoom lens, the zoom lens drive position information may include the position indication values ​​of zoom lens 36a and lens 36c, and the movement directions of zoom lens 36a and lens 36c.

[0145] In the above embodiment, the case where an instruction to turn the camera power on and off is input using the power button (operation unit 29) has been described, but the operation unit 29 that instructs the power on and off may be different.

[0146] In the above embodiment, the body-side control unit 23 changes the display of the focal length value 281 displayed on the display unit 28 based on the display focal length information, but the body-side control unit 23 may, for example, perform at least one of changing the display, controlling the exposure, and controlling the detection of the focus state based on the display focal length information. In addition, the body-side control unit 23 changes the display of the indicator 282 displayed on the display unit 28 based on the control focal length information, but the body-side control unit 23 may, for example, perform at least one of changing the display, controlling the exposure, and controlling the detection of the focus state based on the control focal length information.

[0147] Furthermore, in the above embodiment, the lens-side control unit 33 transmits the focal length calculated based on the position of the zoom lens 36a as the display focal length information and the control focal length information. However, the lens-side control unit 33 may transmit the value indicating the position of the zoom lens 36a itself as the display focal length information and the control focal length information. In this case, the lens-side control unit 33 transmits the number of divisions of the magnification range along with the value indicating the position of the zoom lens 36a. In this case, the body-side control unit 23 calculates the focal length based on the number of divisions and the value indicating the position of the zoom lens 36a.

[0148] Furthermore, in the above embodiment, whether or not an interchangeable lens 3 is attached to the camera body 2 is determined based on the signal level of the LDET(B) terminal, but this is not limited to this. For example, as described in Japanese Patent Application Laid-Open No. 2019-78933, the camera body 2 may be provided with a switch that detects the state of a lock pin that fixes the relative position of the camera body 2 and the interchangeable lens 3, and it may be determined that the interchangeable lens 3 is attached when the switch is in the on state and the signal level of the LDET(B) terminal is low.

[0149] Furthermore, in the above embodiment, the interchangeable lens 3 has been described as an accessory, but the accessory may be something other than the interchangeable lens 3. Examples of accessories include a teleconverter, a mount conversion adapter, and an interchangeable lens attached via a teleconverter or a mount conversion adapter.

[0150] Furthermore, in the above embodiment, zoom lens drive position information and focus position information are stored in the restoration table, but if the interchangeable lens 3 is, for example, a single focus lens, only focus position information may be stored in the restoration table, and when the power to the camera body 2 is turned on, only the state of the focus lens 36b at the time the power was last turned off may be restored.

[0151] Furthermore, in the above embodiment, regardless of the user's settings, both the zoom lens drive position information and the focus lens position information may be stored, and the zoom lens drive position information and the focus lens position information stored in the body-side memory unit 25 may be transmitted to the interchangeable lens 3 according to the user's settings.

[0152] The above-described embodiment is a preferred example of implementation, but is not limited to this, and various modifications are possible within the scope of the gist, and any constituent elements may be combined.

[0153] REFERENCE SIGNS LIST 1 camera system 2 camera body 3 interchangeable lens 23 body side control section 24 body side communication section 24a first body side communication section 24b second body side communication section 27 imaging element 28 display section 29 operation section 34 lens side communication section 34a first lens side communication section 34b second lens side communication section 36 imaging optical system 36a zoom lens 36b focus lens 37 first drive section OA optical axis

Claims

1. An interchangeable lens that can be attached to a camera body, an optical system including a zoom lens that is movable in an optical axis direction and whose magnification can be changed by moving the zoom lens; a communication unit including a transmitter that repeatedly transmits to the camera body a signal sequence used as a target position in a drive instruction from the camera body, and a receiver that receives the signal sequence from the camera body as the target position in the drive instruction; a drive unit that drives the zoom lens to a target position indicated by the signal sequence; An interchangeable lens equipped with

2. The interchangeable lens according to claim 1 , wherein the signal sequence is generated based on a detected position of the zoom lens.

3. 2. The interchangeable lens according to claim 1, wherein the signal sequence is first magnification information indicating a magnification state of the optical system.

4. the signal sequence is not used for control inside the camera body; The interchangeable lens according to any one of claims 1 to 3.

5. the first magnification information indicates a magnification state within a magnification range of the optical system at a first resolution; the communication unit repeatedly transmits to the camera body second magnification information, which indicates a magnification state within a magnification range of the optical system at a second resolution coarser than the first resolution, and the first magnification information; the communication unit receives the first magnification change information from the camera body but does not receive the second magnification change information; The interchangeable lens according to claim 3 .

6. An interchangeable lens that can be attached to a camera body, an optical system having a zoom lens that is movable in the direction of an optical axis and capable of varying magnification; a communication unit that communicates with the camera body; Equipped with the communication unit transmits to the camera body first magnification information indicating a state of magnification change in a magnification change range of the optical system at a first resolution and second magnification information indicating the state at a second resolution coarser than the first resolution, and receives the first magnification change information from the camera body but does not receive the second magnification change information; Interchangeable lens.

7. the communication unit transmits third magnification information indicating a state of magnification change within a magnification change range of the optical system at a third resolution finer than the second resolution to the camera body; 7. The interchangeable lens according to claim 5 or 6.

8. When power supply from the camera body starts, the communication unit transmits identification information for identifying the interchangeable lens to the camera body, and receives the first magnification change information after transmitting the identification information.

7. The interchangeable lens according to claim 5 or 6.

9. the optical system includes a focus lens that can change a focus position of the optical system by moving in an optical axis direction, the communication unit includes a first communication unit that communicates with the camera body, and a second communication unit that communicates with the camera body independently of the first communication unit, in-focus position information indicating a position of the focus lens is transmitted to the camera body by the second communication unit and received from the camera body by the first communication unit; the first magnification change information is transmitted to the camera body by the first communication unit and received from the camera body by the first communication unit; 7. The interchangeable lens according to claim 5 or 6.

10. the optical system includes a plurality of zoom lenses each having a different movement amount and movement direction when changing magnification; the first magnification change information includes information representing the movement directions of the plurality of zoom lenses when the states of the plurality of zoom lenses become the states indicated by the first magnification change information; 7. The interchangeable lens according to claim 5 or 6.

11. the first variable magnification information includes information indicating whether the optical system has changed from a wide-angle state to a telephoto state or from the telephoto state to the wide-angle state when the state of the zoom lens becomes the state indicated by the first variable magnification information; 7. The interchangeable lens according to claim 5 or 6.

12. A camera body to which an interchangeable lens having a variable magnification optical system can be attached, a communication unit that repeatedly receives first magnification change information indicating a magnification change state of the optical system from the interchangeable lens; an operation unit that accepts input of a first instruction and a second instruction; a storage unit that stores the first magnification change information received from the interchangeable lens when the first instruction is input via the operation unit; Equipped with when the second instruction is input via the operation unit, the communication unit transmits the first magnification change information stored in the storage unit to the interchangeable lens. Camera body.

13. the first magnification information indicates a magnification state within a magnification range of the optical system at a first resolution; the communication unit receives, from the interchangeable lens, second magnification information indicating a state of magnification change within a magnification change range of the optical system at a second resolution coarser than the first resolution, and the first magnification change information, and when the second instruction is input, transmits the first magnification change information to the interchangeable lens but does not transmit the second magnification change information; 13. The camera body according to claim 12.

14. the communication unit receives identification information for identifying the interchangeable lens, When an instruction to turn off the power is input as the first instruction, the first magnification change information is stored in the storage unit together with the identification information, and then the power is turned off; When an instruction to turn on a power source is input as the second instruction, the identification information of the interchangeable lens is received by the communication unit, and when the received identification information matches the identification information stored in the storage unit, the communication unit transmits the first magnification change information stored in the storage unit to the interchangeable lens.

14. The camera body according to claim 12 or 13.

15. If the first magnification change information is not stored in the storage unit, information instructing the interchangeable lens to transition the state of the optical system to a predetermined state stored in the interchangeable lens is transmitted to the interchangeable lens.

14. The camera body according to claim 12 or 13.

16. the communication unit receives in-focus position information indicating a position of a focus lens included in the optical system; the operation unit is capable of accepting an operation for setting whether or not to transmit each of the first magnification change information and the focus position information stored in the storage unit to the interchangeable lens when an instruction to turn on a power source is input as the second instruction.

14. The camera body according to claim 12 or 13.

17. when an instruction to turn on a power source is input as the second instruction, the communication unit transmits either a first magnification change instruction for transitioning a magnification change state of the optical system to a state indicated by the first magnification change information stored in the storage unit, or a second magnification change instruction for transitioning to a predetermined state stored in the interchangeable lens; 17. The camera body according to claim 16, wherein, when an instruction to turn on the power is input as the second instruction, the position on the optical axis of the focus lens indicated by the focus position information transmitted by the communication unit differs depending on whether the first magnification instruction or the second magnification instruction is transmitted.

18. A camera system comprising an accessory having a variable magnification optical system and a camera body to which the accessory can be attached, The accessory is an accessory side transmitter that repeatedly transmits a signal sequence that indicates a magnification state of the optical system; an accessory-side receiving unit that receives the signal sequence as a target state in a drive command from the camera body; Equipped with The camera body includes: a body side receiving unit that repeatedly receives the signal sequence indicating the magnification state of the optical system from the accessory; a body side transmitter that transmits the signal sequence to the accessory as the target state for driving the optical system without changing the signal sequence; A camera system comprising:

19. 1. A method for indicating a state of an accessory of a camera body to which an accessory can be attached, comprising: repeatedly receiving a signal sequence indicating a state of the accessory detected by the accessory; transmitting one of the received signal sequences as a target state in a drive instruction without any change; Instruction method.