Accessories

Abstract

We provide accessories that enable stable communication with the camera body. [Solution] The accessory is an accessory that can be attached to a camera body and comprises a communication unit including a circuit for communicating with the camera body, a ready terminal used to indicate whether or not communication with the camera body via the communication unit is possible, a first data terminal to which a first data signal is input from the camera body to the communication unit, a second data terminal to which the communication unit outputs a second data signal to the camera body, a first clock terminal to which the communication unit outputs a clock signal to the camera body, and a third data terminal to which the communication unit outputs a third data signal to the camera body in synchronization with the clock signal, wherein the ready terminal, the first data terminal, the second data terminal, the first clock terminal, and the third data terminal are arranged in order.

Description

Technical Field

[0001] The present invention relates to an accessory.

Background Art

[0002] An accessory that can be attached to and detached from a camera body is known (for example, Patent Document 1). Conventionally, it has been necessary to attach an accessory to the camera body in a state where it can be properly used.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] An accessory according to a first aspect of the present invention is an accessory that can be attached to a camera body, and includes a communication unit including a circuit that communicates with the camera body, a ready terminal used to indicate whether communication with the camera body via the communication unit is possible, a first data terminal to which a first data signal from the camera body is input, a second data terminal that outputs a second data signal from the communication unit to the camera body, a first clock terminal that outputs a clock signal from the communication unit to the camera body, and a third data terminal that outputs a third data signal from the communication unit to the camera body in synchronization with the clock signal, and the ready terminal, the first data terminal, the second data terminal, the first clock terminal, and the third data terminal are arranged side by side in order.

Brief Description of the Drawings

[0005] [Figure 1] A diagram schematically showing the configuration of a camera system [Figure 2] A circuit diagram schematically showing the electrical connection between a camera body and an interchangeable lens according to a first embodiment [Figure 3]Timing chart showing an example of command data communication [Figure 4] Timing chart showing an example of hotline communication [Figure 5] A schematic front view showing the camera body's mount surface as seen from the interchangeable lens side. [Figure 6] A schematic front view showing the mount surface of an interchangeable lens as seen from the camera body. [Figure 7] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the second embodiment. [Figure 8] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the third embodiment. [Figure 9] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the fourth embodiment. [Figure 10] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the fifth embodiment. [Figure 11] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the sixth embodiment. [Figure 12] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the seventh embodiment. [Figure 13] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the eighth embodiment. [Figure 14] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the ninth embodiment. [Figure 15] A schematic circuit diagram showing the electrical connection between the camera body and the interchangeable lens according to the 10th embodiment. [Modes for carrying out the invention]

[0006] (First Embodiment) Figure 1 is a schematic diagram showing the configuration of a camera system 1 according to the first embodiment. The camera system 1 includes a camera body 2 and an interchangeable lens 3 as an example of an accessory that can be attached to the camera body 2.

[0007] The interchangeable lens 3 includes a lens-side mount 31, a lens-side terminal holding part 32, a lens-side control unit 33 having a lens-side communication unit 34, a lens-side memory unit 35, an imaging optical system 36, and a drive unit 37. The lens-side mount 31 and the lens-side terminal holding part 32 will be described in detail later.

[0008] The lens-side control unit 33 consists of a microcomputer and its peripheral circuits. The lens-side communication unit 34 performs data communication with the camera body 2, as described later. The lens-side communication unit 34 is connected to a group of lens-side terminals (described later) provided on the lens-side terminal holding unit 32. 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 predetermined control programs, etc., that the lens-side control unit 33 will execute. The lens-side control unit 33 controls the interchangeable lens 3 by reading the control program from the lens-side storage unit 35 and executing the program.

[0009] The imaging optical system 36 forms an image of the subject on the imaging surface of the image sensor 27, which will be described later. The optical axis O of the imaging optical system 36 substantially coincides with the center position of the lens-side mount 31 and the body-side mount 21, which will be described later. The imaging optical system 36 in Figure 1 schematically includes a lens 36a, a focus lens 36b, and a lens 36c. The focus lens 36b is a lens that adjusts the imaging position of the subject image. The drive unit 37 is connected to the lens-side control unit 33 and has actuators, etc., which are not shown. The drive unit 37 drives the focus lens 36b in the optical axis direction (+Z direction, -Z direction) using these actuators, etc.

[0010] The camera body 2 includes a body-side mount 21, a body-side terminal holding part 22, a body-side control unit 23 having a body-side communication unit 24, a body-side memory unit 25, a power supply unit 26, an image sensor 27, and a switch 28 for detecting the state of a lock pin, which will be described later.

[0011] The body-side control unit 23 consists of a microcomputer and its peripheral circuits. While the body-side control unit 23 performs various controls on the body, only the communication-related parts are described here, and other functions are omitted. The body-side communication unit 24 performs data communication with the interchangeable lens 3, as described later. The body-side communication unit 24 is connected to the body-side terminals (described later) provided on the body-side terminal holder 22. Some of the terminals on the body-side terminal holder 22 are connected to the body-side control unit 23, as described later. 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 predetermined control programs, etc., that the body-side control unit 23 executes. 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 them.

[0012] The power supply unit 26 has a power source and supplies power to the camera body 2 and the interchangeable lens 3. The power supply unit 26 is connected to the body-side terminal group (described later) provided on the body-side terminal holding unit 22 and to the body-side control unit 23. 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 and captures an image of the subject and outputs an image signal. The processing of the output image signal will not be explained.

[0013] Figure 2 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3. The body-side terminal holder 22 has the LDET(B) terminal, VBAT(B) terminal, PGND(B) terminal, V33(B) terminal, GND(B) terminal, RDY(B) terminal, DATAB(B) terminal, CLK(B) terminal, DATAL(B) terminal, HCLK(B) terminal, and HDATA(B) terminal. These 11 body-side terminals are collectively referred to as the body-side terminal group.

[0014] The LDET(B) terminal is a terminal used for detecting the attachment and detachment of the interchangeable lens 3. The LDET(B) terminal is connected to the body-side control unit 23 via the resistor R2. A power supply V33 supplied from the power supply unit 26 is connected between the resistor R2 and the body-side control unit 23 via the resistor R1, and the LDET(B) terminal is pulled up.

[0015] The VBAT(B) terminal, PGND(B) terminal, V33(B) terminal, and GND(B) terminal are terminals of the power supply system 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 for supplying power to the interchangeable lens 3. The drive unit 37 of the interchangeable lens 3 is driven by the power supplied via the VBAT(B) terminal. The operation of the drive unit 37 requires a voltage and current larger than those of the lens-side control unit 33, and the power supply voltage applied by the power supply unit 26 to the VBAT(B) terminal is about 10 V at maximum. In the following description, the voltage applied by the power supply unit 26 to the VBAT(B) terminal is referred to as the drive system voltage. That is, the camera body 2 supplies the drive system power supply voltage from the VBAT(B) terminal to the interchangeable lens 3. The PGND(B) terminal is a ground terminal corresponding to the VBAT(B) terminal and is used as the ground potential (ground) of the drive system power supply voltage.

[0016] The V33(B) terminal is a terminal used for supplying power to the interchangeable lens 3. The power supplied from the power supply unit 26 via the V33(B) terminal operates the lens-side control unit 33 and the like. Each unit such as the lens-side control unit 33 operates with a smaller voltage and current than the drive unit 37. The voltage applied by the power supply unit 26 to the V33(B) terminal is about 3.3 V at maximum. In the following description, the voltage applied by the power supply unit 26 to the V33(B) terminal is referred to as the circuit system voltage. That is, the camera body 2 supplies the circuit system power supply voltage from the V33(B) terminal to the interchangeable lens 3. The GND(B) terminal is a ground terminal corresponding to the V33(B) terminal and is used as the ground potential (ground) of the circuit system power supply voltage.

[0017] The RDY(B) terminal is connected to the body-side communication unit 24. The DATAB(B) terminal, CLK(B) terminal, DATAL(B) terminal, HCLK(B) terminal, and HDATA(B) terminal are communication terminals connected to the body-side communication unit 24. The RDY(B) terminal, DATAB(B) terminal, CLK(B) terminal, and DATAL(B) terminal are used for command data communication, which will be described later. The HCLK(B) terminal and HDATA(B) terminal are also connected to the body-side communication unit 24 and are used for hotline communication, which will be described later. In Figure 2, the signal flow is shown by arrows. The potential of the RDY(B) terminal indicates whether the interchangeable lens 3 is capable of command data communication. The DATAB(B) terminal is the terminal to which a data signal is output toward the interchangeable lens 3. The CLK(B) terminal is the terminal to which a clock signal (C clock signal) is output from the camera body 2 toward the interchangeable lens 3.

[0018] The DATAL(B) terminal is the terminal into which the data signal from interchangeable lens 3 is input.

[0019] The HCLK(B) terminal is where the clock signal (H clock signal) from interchangeable lens 3 is input. The HDATA(B) terminal is where the data signal from interchangeable lens 3 is input.

[0020] The lens-side terminal retaining section 32 has LDET(L) terminal, VBAT(L) terminal, PGND(L) terminal, V33(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, CLK(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal. These 11 lens-side terminals are collectively referred to as the lens-side terminal group. When the interchangeable lens 3 is attached to the camera body 2, the body-side terminal and the lens-side terminal are electrically connected as shown by the dashed line in Figure 2. Specifically, the LDET(L) terminal is connected to the LDET(B) terminal, the VBAT(L) terminal is connected to the VBAT(B) terminal, the PGND(L) terminal is connected to the PGND(B) terminal, the V33(L) terminal is connected to the V33(B) terminal, the GND(L) terminal is connected to the GND(B) terminal, the RDY(L) terminal is connected to the RDY(B) terminal, the DATAB(L) terminal is connected to the DATAB(B) terminal, the CLK(L) terminal is connected to the CLK(B) terminal, the DATAL(L) terminal is connected to the DATAL(B) terminal, the HCLK(L) terminal is connected to the HCLK(B) terminal, and the HDATA(L) terminal is connected to the HDATA(B) terminal. The signals input to or output to each lens-side terminal correspond to the corresponding body-side terminals they contact.

[0021] The LDET(L) terminal is used to detect the attachment or detachment of the interchangeable lens 3. The LDET(L) terminal is connected to ground (GND) via resistor R3. When the interchangeable lens 3 is attached to the camera body 2, the LDET(L) terminal and the LDET(B) terminal are electrically connected, and the LDET(B) terminal is pulled down. This allows the camera body 2 to detect that the interchangeable lens 3 has been attached.

[0022] The VBAT(L) terminal, PGND(L) terminal, V33(L) terminal, and GND(L) terminal are power supply terminals that are electrically connected to the VBAT(B) terminal, PGND(B) terminal, V33(B) terminal, and GND(B) terminal, respectively. In Figure 2, the direction of the supplied power is indicated by arrows. The power supplied via the VBAT(L) terminal drives the drive unit 37 of the interchangeable lens 3. The PGND(L) terminal is the ground terminal corresponding to the VBAT(L) terminal and is used as the ground potential (ground) of the power supply voltage of the drive system. A so-called bypass capacitor C1 is connected between the VBAT(L) terminal and the PGND(L) terminal.

[0023] The V33(L) terminal is used to supply power to the interchangeable lens 3. The V33(L) terminal and the GND(L) terminal are connected to various parts such as the lens-side control unit 33. The lens-side control unit 33 and other components are operated by power supplied from the power supply unit 26 via the V33(B) terminal. The GND(L) terminal is the grounding terminal corresponding to the V33(B) terminal and is used as the ground potential (ground) of the power supply voltage of the circuit system. A bypass capacitor C2 is connected between the V33(L) terminal and the GND(L) terminal.

[0024] The RDY(L) terminal is connected to the body-side communication unit 24 via the RDY(B) terminal. The DATAB(L) terminal, CLK(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal are communication system terminals that are electrically connected to the DATAB(B) terminal, CLK(B) terminal, DATAL(B) terminal, HCLK(B) terminal, and HDATA(B) terminal, respectively. The RDY(L) terminal, DATAB(L) terminal, CLK(L) terminal, and DATAL(L) terminal are used for command data communication, which will be described later. The HCLK(L) terminal and HDATA(L) terminal are used for hotline communication, which will be described later.

[0025] The VBAT(L) terminal and PGND(L) terminal are connected to the drive unit 37 via the lens-side control unit 33. The V33(L) terminal and GND(L) terminal are connected to the lens-side control unit 33 and other parts. The RDY(L) terminal, DATAB(L) terminal, CLK(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal are each connected to the lens-side communication unit 34.

[0026] (Explanation of command data communication) Command data communication is the process by which the body-side control unit 23 transmits control commands and control data to the lens-side control unit 33 of the interchangeable lens 3, and the lens-side control unit 33 transmits response data and other data to the body-side control unit 23. Command data communication is full-duplex communication. Command data communication is performed via 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 body-side communication unit 24 and the lens-side communication unit 34.

[0027] The body-side control unit 23 transmits various control commands and control contents to the interchangeable lens 3 via command data communication through the body-side communication unit 24 and the lens-side communication unit 34, and receives response contents and other data from the interchangeable lens 3, thereby transmitting and receiving various information with the interchangeable lens 3. Control commands here refer to, for example, commands to transmit lens information. Various information received from the interchangeable lens 3 includes, for example, model information of the interchangeable lens 3 and information indicating optical characteristics such as the focal length of the imaging optical system 36. Various information transmitted to the interchangeable lens 3 includes, for example, control commands such as lens drive instructions, control contents such as the amount of lens drive, and model information of the camera body 2. Control commands also include drive commands for the focus lens 36b. The lens-side control unit 33 receives various control commands from the body-side control unit 23, acquires control contents from the body-side control unit 23, and transmits response contents (for example, information regarding the execution status of the initialization process, such as initialization in progress or initialization completed, in response to an initialization control command from the camera body 2) to the body-side control unit 23 via command data communication.

[0028] Figure 3 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 command data communication is possible or not for the lens-side control unit 33. 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.

[0029] At the start of command data communication (T1), if the signal level of the RDY(B) terminal is low (L level), the body-side control unit 23 outputs a C clock signal 401 from the CLK(B) terminal via the body-side communication unit 24. That is, the body-side control unit 23 transmits the C 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 C clock signal 401 in Figure 3 alternates between high and low levels is, for example, 8 MHz. Synchronized with the C clock signal 401, the body-side control unit 23 outputs a body-side command signal 402, which is a control command, from the DATAB(B) terminal. 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, shown by the switching between high and low levels of DATAB in Figure 3, is a signal representing the control that the body-side control unit 23 instructs the lens-side control unit 33 to perform via command data communication. For example, the body-side command signal 402 is a signal that indicates a request for model information of the interchangeable lens 3, or a signal that indicates an instruction to drive the focus lens 36b. As shown in Figure 3, the timing at which the body-side command signal 402 is transmitted is different from the period of the C clock signal 401. The command signal 402 is transmitted periodically at a minimum interval of approximately 8 milliseconds during initialization processing when the camera system 1 is powered on, and during termination processing when the power is turned off, but otherwise it is transmitted at arbitrary timings.

[0030] When the lens-side control unit 33 receives the body-side command signal 402 via the lens-side communication unit 34, it performs an inspection process to check for communication errors in the body-side command signal 402 using the error detection code (e.g., checksum data) contained in the body-side command signal 402. After that, the lens-side control unit 33 sets the signal level of the RDY(L) terminal to a high level (H level) (T2). If the signal level of the RDY(B) terminal is high, the body-side control unit 23 does not transmit the C clock signal or the body-side command signal 402. The lens-side control unit 33 starts the first control process 404 based on the instructions of the received body-side command signal 402.

[0031] When the first control process 404 is completed, the lens-side control unit 33 sets the signal level of the RDY(L) terminal to a low level (L level) via the lens-side communication unit 34 (T3). When the signal level of the RDY(B) terminal becomes low, the body-side control unit 23 outputs a C clock signal 405 from the CLK(B) terminal. The frequency at which the C clock signal 405 alternates between high and low levels is the same as that of the C clock signal 401, for example, 8MHz. That is, the body-side control unit 23 transmits the C clock signal 405 to the lens-side control unit 33 via the CLK(B) terminal and the CLK(L) terminal. Furthermore, the body-side control unit 23 does not transmit or receive the body-side data signal 406 or the lens-side data signal 407 when the signal level of the RDY(B) terminal is high.

[0032] The body-side control unit 23 outputs a body-side data signal 406 from the DATAB(B) terminal via the body-side communication unit 24 in synchronization with the C 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 that represents the control parameters of the body-side command signal 402. For example, if the body-side command signal 402 is a signal that indicates an instruction to drive the focus lens 36b, the corresponding body-side data signal 406 is a signal that represents the amount of drive of the focus lens 36b. Alternatively, the body-side data signal 406 is a signal that represents information required by the lens-side control unit 33 in command data communication (such as camera body model information).

[0033] Furthermore, when the C clock signal 405 is input to the CLK(L) terminal, the lens-side control unit 33 outputs the lens-side data signal 407 from the DATAL(L) terminal in synchronization with the C clock signal 405. The lens-side data signal 407, indicated by the switching between high and low levels of DATAL in Figure 3, 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 indicating a request for model information of interchangeable lens 3, the corresponding lens-side data signal 407 is a signal representing the model information of interchangeable lens 3. As shown in Figure 3, the timing of transmission of the body-side data signal 406 and the lens-side data signal 407 differs from the period of the C clock signal 405. The body-side data signal 406 and the lens-side data signal 407 are transmitted periodically at a minimum interval of approximately 8 milliseconds during initialization processing when the camera system 1 is powered on, and during termination processing when the power is turned off, but otherwise they are transmitted at arbitrary timings.

[0034] When the lens-side control unit 33 has finished transmitting the lens-side data signal 407, it raises the signal level of the RDY(L) terminal to high again (T4). Based on the instructions of the received body-side data signal 406, the lens-side control unit 33 starts the second control process 408 (described later).

[0035] Here, we will describe the first control process 404 and the second control process 408 performed by the lens-side control unit 33. For example, we will describe the case where the received body-side command signal 402 requests specific information about the interchangeable lens 3. As the first control process 404, the lens-side control unit 33 performs a process to generate the requested information as a lens-side data signal 407. The lens-side data signal 407 generated in the first control process 404 is transmitted to the body-side communication unit 24 of the body-side control unit 23 via the lens-side communication unit 34, the DATAL(L) terminal, and the DATAL(B) terminal.

[0036] For example, consider the case where 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 performs a first control process 404, which generates a signal indicating that it has received a signal indicating an instruction to drive the focus lens 36b. The signal generated in the first control process 404 is transmitted as a lens-side data signal 407 to the body-side communication unit 24 of the body-side control unit 23 via the lens-side communication unit 34, the DATAL(L) terminal, and the DATAL(B) terminal. The lens-side control unit 33 performs a second control process 408, which drives the lens by the amount specified by the body-side data signal 406.

[0037] When the second control process 408 is completed, the lens-side control unit 33 lowers the RDY(L) terminal to a low level via the lens-side communication unit 34 (T5).

[0038] The communication performed at the timings T1 to T5 described above constitutes 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 a single control command and control content (control data).

[0039] As described above, the lens-side control unit 33 receives control commands and 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 a so-called full-duplex communication.

[0040] (Explanation of hotline communication) Another communication system involves the one-way transmission of data from the lens-side control unit 33 of the interchangeable lens 3 to the body-side control unit 23 of the camera body 2; this is called hotline communication. Hotline communication is data communication performed between the body-side control unit 23 and the lens-side control unit 33 via the body-side communication unit 24 and the lens-side communication unit 34, using the HCLK(B) terminal, HCLK(L) terminal, HDA(B) terminal, and HDA(L) terminal. The body-side control unit 23 obtains information regarding the state of the interchangeable lens 3 from the lens-side control unit 33 of the interchangeable lens 3 via hotline communication. This information regarding the state of the interchangeable lens 3 includes, for example, the position of the focus lens 36b, the position of the image stabilization lens (not shown), and the drive position of the aperture blades. The image stabilization lens is a component that can be moved (driven) to include a component in a direction perpendicular to the optical axis, and the aperture is a component that can be moved (driven) to change the size of the opening through which the light beam passes. This hotline communication is a type of communication in which, once a communication start instruction is sent from the camera body via command data communication, the lens-side control unit 33 autonomously (independently) transmits lens data to the body-side control unit 23, regardless of the command data communication, until a communication end instruction is sent.

[0041] Figure 4 is an example of a timing chart showing the timing of hotline communication. When the lens-side control unit 33 receives a command to start hotline communication from the camera body-side control unit 23 via command data communication (T6), it performs generation processing 501. Generation processing 501 is a process that acquires the state of the lens with a sampling period of, for example, 1 millisecond and generates a lens signal 503 for hotline communication. Once the generation of the lens signal 503 is complete (T7), the lens-side control unit 33 outputs an H clock signal 502 from the HCLK(L) terminal via the lens-side communication unit 34. That is, it transmits the H clock signal 502 to the body-side control unit 23 via the HCLK(L) terminal and the HCLK(B) terminal. The frequency at which the H clock signal 502 in Figure 4 alternates between high and low levels is, for example, 2.5MHz to 8MHz. In other words, the frequency of the H clock signal 502 for hotline communication is the same as or lower than the frequency of the C clock signal 401 for command data communication. In other words, the period of the H clock signal 502 for hotline communication is the same as or longer than the period of the C clock signal 401 for command data communication.

[0042] The lens-side control unit 33 outputs the lens signal 503 (for example, information regarding the position of the focus lens 36b) generated in the generation process 501 via the lens-side communication unit 34, synchronized with the H clock signal 502, from the HDATA(L) terminal. That is, the lens-side control unit 33 transmits the lens signal 503 to the body-side communication unit 24 of the body-side control unit 23 via the lens-side communication unit 34, the HDATA(L) terminal, and the HDATA(B) terminal. The lens signal 503, shown by the switching between high and low levels of HDATA in Figure 4, is the signal that the lens-side control unit 33 transmits to the body-side control unit 23 via hotline communication. The H clock signal 502 and the lens signal 503 terminate their output at timing T8. The lens-side control unit 33 repeatedly transmits lens data via hotline communication at regular intervals (e.g., 1 millisecond) until it receives a command data communication instruction to stop transmitting the lens signal 503. As shown in Figure 4, the timing of the transmission of lens data via hotline communication is different from the period of the H clock signal 502. The transmission interval of lens data via hotline communication is shorter than the transmission and reception interval of control commands and control data via command data communication as described above.

[0043] Command data communication and hotline communication can be performed in parallel, either partially or entirely. 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 in progress. Conversely, command data communication can also be started or ended while hotline communication is in progress.

[0044] As explained above, hotline communication is conducted independently of command communication. The lens-side control unit 33 transmits information regarding the status of the interchangeable lens 3 to the body-side control unit 23 via hotline communication, regardless of command communication. Therefore, the body-side control unit 23 can continuously monitor the status of the interchangeable lens 3 even during command communication. As a result, the body-side control unit 23 can continuously monitor the position of the focus lens 36b, enabling, for example, high-speed autofocus control. The same applies to image stabilization control and aperture control. Furthermore, the body-side control unit 23 can issue various instructions to the interchangeable lens 3 via command communication at any time, even while the lens-side control unit 33 is performing hotline communication.

[0045] (Explanation of lens mount mechanism) The camera system 1 of this embodiment is equipped with a so-called bayonet-type lens mount mechanism. The body-side mount 21 of the camera body 2 and the lens-side mount 31 of the interchangeable lens 3 will be described in order below.

[0046] Figure 5(a) is a schematic diagram showing the mount of the camera body 2 as seen from the interchangeable lens 3 side. The camera body 2 includes the body-side mount 21 and body-side terminal retaining portion 22 described in Figure 1. The body-side mount 21 has an annular reference surface of a certain width. Furthermore, the body-side mount 21 has a body-side first claw portion 29a, a body-side second claw portion 29b, a body-side third claw portion 29c, and a body-side fourth claw portion 29d. In the following description, these four claw portions will be collectively referred to as the body-side claw portion 29.

[0047] The body-side claw portions 29 are arranged at intervals from one another along the circular opening of the body-side mount 21. As shown in Figure 5(a), the first body-side claw portion 29a is located in the upper right position, the second body-side claw portion 29b is located in the upper left position, the third body-side claw portion 29c is located in the lower left position, and the fourth body-side claw portion 29d is located in the lower right position.

[0048] The circumferential lengths of the body-side first claw portion 29a to the body-side fourth claw portion 29d are all different. Specifically, the body-side first claw portion 29a is the longest, the body-side third claw portion 29c is the second longest, the body-side fourth claw portion 29d is the third longest, and the body-side second claw portion 29b is the shortest.

[0049] The body-side claw portion 29 protrudes from the body-side mount 21 toward the center of the opening, and on the circumference of the opening, there are parts where the body-side claw portion 29 is present and parts where it is not. In the following description, the space 40a between the body-side first claw portion 29a and the body-side fourth claw portion 29d on the circumference of the opening of the body-side mount 21 will be referred to as the body-side first insertion / removal portion 40a. Similarly, the space 40b between the body-side first claw portion 29a and the body-side second claw portion 29b will be referred to as the body-side second insertion / removal portion 40b, the space 40c between the body-side second claw portion 29b and the body-side third claw portion 29c will be referred to as the body-side third insertion / removal portion 40c, and the space 40d between the body-side third claw portion 29c and the body-side fourth claw portion 29d will be referred to as the body-side fourth insertion / removal portion 40d. These four body-side insertion / removal portions will be collectively referred to as the body-side insertion / removal portion 40.

[0050] A body-side terminal holding portion 22 is provided inside the opening of the body-side mount 21. The body-side terminal holding portion 22 has an arc shape corresponding to the annular shape of the body-side mount 21. The body-side terminal holding portion 22 is positioned parallel to the opening of the body-side mount 21 and above the opening of the body-side mount 21, preferably positioned in the center of the upper part as shown in Figure 5(a). As described above, the body-side terminal holding portion 22 has a plurality of body-side terminals. The plurality of body-side terminals are arranged in an arc shape in a single line inside the body-side mount 21 on the body-side terminal holding portion 22. As shown in Figure 5(a), the plurality of body-side terminals are arranged from right to left as follows: HDATA(B), HCLK(B), DATAL(B), CLK(B), DATAB(B), RDY(B), GND(B), V33(B), PGND(B), VBAT(B), and LDET(B) on the far left, totaling 11 terminals. Each of the terminals on the camera body is a conductive pin. The terminals on the camera body are pushed in the -Z direction (Figure 1) by a spring or the like (not shown). The -Z direction is the direction toward the interchangeable lens 3 attached to the camera, and is the direction of the subject.

[0051] The body-side mount 21 has a hole through which the lock pin 42 passes. The hole through which the lock pin 42 passes is located to the upper right of the body-side fourth claw portion 29d. In other words, on the annular reference plane of the body-side mount 21, the hole for the lock pin 42 is located between the region where the body-side fourth claw portion 29d is located and the region where the body-side first claw portion 29a is located within the opening of the body-side mount 21. The lock pin 42 is pushed in the -Z direction (Figure 1) by a spring or the like (not shown).

[0052] Figure 5(b) is a schematic diagram of the camera body 2 mount with the body-side mount 21 removed, viewed from the interchangeable lens 3 side. A first leaf spring 41a is provided at a position corresponding to the body-side first claw portion 29a (on the back side of the body-side first claw portion 29a). Similarly, a second leaf spring 41b is provided at a position corresponding to the body-side second claw portion 29b (on the back side of the body-side second claw portion 29b), a third leaf spring 41c is provided at a position corresponding to the body-side third claw portion 29c (on the back side of the body-side third claw portion 29c), and a fourth leaf spring 41d is provided at a position corresponding to the body-side fourth claw portion 29d (on the back side of the body-side fourth claw portion 29d). In the following description, these four leaf springs will be collectively referred to as leaf spring 41. The leaf spring 41 presses the lens-side claw portion, which will be described later, in the +Z direction (towards the camera body 2).

[0053] Figure 6 is a schematic diagram showing the mount of the interchangeable lens 3 as seen from the camera body 2. The interchangeable lens 3 includes the lens-side mount 31 and the lens-side terminal retaining portion 32 described in Figure 1. The lens-side mount 31 has an annular reference surface having a certain width. When the interchangeable lens 3 is attached to the camera body 2, the annular reference surface of the lens-side mount 31 contacts the annular reference surface of the body-side mount 21 described above. Furthermore, the lens-side mount 31 has a cylindrical portion extending in the direction of the optical axis on its inner circumference. The lens-side mount 31 has a lens-side first claw portion 39a, a lens-side second claw portion 39b, a lens-side third claw portion 39c, and a lens-side fourth claw portion 39d spaced apart from each other along the outer circumference of the cylindrical portion. In the following description, these four claw portions will be collectively referred to as the lens-side claw portion 39.

[0054] The lens-side claw portion 39 is provided so as to protrude from the outer circumference of the cylindrical portion of the lens-side mount 31 toward the outside of the mount (radially from the optical axis O). As shown in Figure 6, the first lens-side claw portion 39a is located in the upper left position, the second lens-side claw portion 39b is located in the upper right position, the third lens-side claw portion 39c is located in the lower right position, and the fourth lens-side claw portion 39d is located in the lower left position. Behind the lens-side claw portion 39 (on the reference plane side of the lens-side mount 31), there is space for the corresponding body-side claw portion 29 to fit into when the interchangeable lens 3 is attached to the camera body 2.

[0055] A lens-side terminal retaining portion 32 is provided inside the opening of the lens-side mount 31. The lens-side terminal retaining portion 32 has an arc shape corresponding to the annular shape of the lens-side mount 31. The lens-side terminal retaining portion 32 is positioned parallel to the opening of the lens-side mount 31 and is located on the upper part of the lens-side mount 31, preferably in the center of the upper part as shown in Figure 6. As described above, the lens-side terminal retaining portion 32 has a plurality of lens-side terminals. The plurality of lens-side terminals are arranged in an arc shape in a single line on the inside of the lens-side mount 31 within the lens-side terminal retaining portion 32. As shown in Figure 6, the plurality of lens-side terminals are arranged from right to left as follows: LDET(L), VBAT(L), PGND(L), V33(L), ​​GND(L), RDY(L), DATAB(L), CLK(L), DATAL(L), HCLK(L), and HDATA(L), totaling 11 terminals. The lens-side terminals are arranged so that their conductive contact surfaces are exposed in the +Z direction (Figure 1). The +Z direction is the direction in which the subject light that has passed through the imaging optical system 36 is directed toward the image sensor 27.

[0056] The lens-side mount 31 has a lock pin receiving portion 43. The lock pin receiving portion 43 is located to the upper left of the lens-side fourth claw portion 39d, as shown in Figure 6. In other words, the lock pin receiving portion 43 is located between the portion of the lens-side mount 31 corresponding to the lens-side first claw portion 39a and the portion corresponding to the lens-side fourth claw portion 39d. The lock pin receiving portion 43 is a groove into which the lock pin 42 fits when the interchangeable lens 3 is attached to the camera body 2. This groove is provided in the -Z direction (Figure 1).

[0057] When the interchangeable lens 3 is attached to the camera body 2, multiple body-side terminals physically contact the corresponding multiple lens-side terminals. This contact electrically connects the multiple body-side terminals to the multiple lens-side terminals. In other words, the multiple body-side terminals and the multiple lens-side terminals become electrically conductive.

[0058] (Attaching interchangeable lenses) This section describes how to attach the interchangeable lens 3 to the camera body 2. When attaching the interchangeable lens 3 to the camera body 2, first, the body-side mount 21 and the lens-side mount 31 are placed opposite each other, the first claw portion 39a on the lens side is aligned with the first insertion / removal portion 40a on the body side, the second claw portion 39b on the lens side is aligned with the second insertion / removal portion 40b on the body side, the third claw portion 39c on the lens side is aligned with the third insertion / removal portion 40c on the body side, and the fourth claw portion 39d on the lens side is aligned with the fourth insertion / removal portion 40d on the body side. Then, the first claw portion 39a on the lens side is inserted into the first insertion / removal portion 40a on the body side, the second claw portion 39b on the lens side is inserted into the second insertion / removal portion 40b on the body side, the third claw portion 39c on the lens side is inserted into the third insertion / removal portion 40c on the body side, and the fourth claw portion 39d on the lens side is inserted into the fourth insertion / removal portion 40d on the body side. At this time, the LDET(L) terminal makes contact with the CLK(B) terminal, the VBAT(L) terminal makes contact with the DATAL(B) terminal, the PGND(L) terminal makes contact with the HCLK(B) terminal, and the V33(L) terminal makes contact with the HDATA(B) terminal.

[0059] From that state, rotate the interchangeable lens 3 in the mounting direction 44 shown in Figures 5 and 6. That is, the first claw portion 29a on the body side enters the space on the back of the first claw portion 39a on the lens side, the second claw portion 29b on the body side enters the space on the back of the second claw portion 39b on the lens side, the third claw portion 29c on the body side enters the space on the back of the third claw portion 39c on the lens side, and the fourth claw portion 29d on the body side enters the space on the back of the fourth claw portion 39d on the lens side. At this time, the multiple lens-side terminals make contact with the multiple body-side terminals in sequence. Alternatively, instead of the interchangeable lens 3, the camera body 2 may be rotated in the opposite direction to the mounting direction 44 shown in Figures 5 and 6.

[0060] When the lens-side claw portion 39 is inserted into the corresponding body-side insertion / removal portion 40 and rotated in the mounting direction 44, for example, the LDET(L) terminal will contact the CLK(B) terminal, DATAB(B) terminal, RDY(B) terminal, GND(B) terminal, V33(B) terminal, PGND(B) terminal, VBAT(B) terminal, and LDET(B) terminal in that order. For example, the VBAT(L) terminal will contact the DATAL(B) terminal, CLK(B) terminal, DATAB(B) terminal, RDY(B) terminal, GND(B) terminal, V33(B) terminal, PGND(B) terminal, and VBAT(B) terminal in that order. For example, the PGND(L) terminal will contact the HCLK(B) terminal, DATAL(B) terminal, CLK(B) terminal, DATAB(B) terminal, RDY(B) terminal, GND(B) terminal, V33(B) terminal, and PGND(B) terminal in that order. For example, the V33(L) terminal makes contact with the HDATA(B) terminal, HCLK(B) terminal, DATAL(B) terminal, CLK(B) terminal, DATAB(B) terminal, RDY(B) terminal, GND(B) terminal, and V33(B) terminal in that order. For example, the GND(L) terminal makes contact with the HDATA(B) terminal, HCLK(B) terminal, DATAL(B) terminal, CLK(B) terminal, DATAB(B) terminal, RDY(B) terminal, and GND(B) terminal in that order.

[0061] For example, the RDY(L) terminal makes contact with the HDATA(B) terminal, HCLK(B) terminal, DATAL(B) terminal, CLK(B) terminal, DATAB(B) terminal, and RDY(B) terminal in that order. For example, the DATAB(L) terminal makes contact with the HDATA(B) terminal, HCLK(B) terminal, DATAL(B) terminal, CLK(B) terminal, and DATAB(B) terminal in that order. For example, the CLK(L) terminal makes contact with the HDATA(B) terminal, HCLK(B) terminal, DATAL(B) terminal, and CLK(B) terminal in that order. For example, the DATAL(L) terminal makes contact with the HDATA(B) terminal, HCLK(B) terminal, and DATAL(B) terminal in that order. For example, the HCLK(L) terminal makes contact with the HDATA(B) terminal and HCLK(B) terminal in that order.

[0062] When the interchangeable lens 3 is rotated by a predetermined angle relative to the camera body 2, it reaches the mounting completion position. In the mounting completion position, the corresponding body-side claw portion 29 and lens-side claw portion 39 face each other in the optical axis direction, and the lock pin 42 is pushed in the -Z direction in Figure 1 and enters the lock pin receiving portion 43. Once the lock pin 42 enters the lock pin receiving portion 43, the interchangeable lens 3 cannot be rotated to be removed from the camera body 2. In other words, when the body-side claw portion 29 and the lens-side claw portion 39 reach the predetermined mounting completion position, the relative position of the body-side mount 21 and the lens-side mount 31 is fixed. The lens-side claw portion 39 is pushed toward the body side (in the +Z direction in Figure 1) by the leaf spring 41. As a result, each of the multiple lens-side terminals contacts each of the multiple body-side terminals that correspond to each of them, and an electrical connection is made.

[0063] In the following description, the state in which the body-side claw portion 29 and the lens-side claw portion 39 have reached a predetermined mounting completion position is referred to as the mounting completion state. The state in which the lens-side claw portion 39 is rotating from the position in which it is inserted into the body-side insertion / removal portion 40 to just before the mounting completion position, or the state in which it is rotating from just before the mounting completion position to the insertion position, is referred to as the mounting in progress state.

[0064] When the lens is attached, 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. When the interchangeable lens 3 is not attached, the body-side control unit 23 does not allow the power supply unit 26 to supply power to the VBAT(B) terminal and the V33(B) terminal.

[0065] When the lens is fully attached, the signal level of the LDET(B) terminal is pulled down to a low level, as described above (Figure 2). When the body-side control unit 23 detects that the signal level of the LDET(B) terminal has become low, it determines that the interchangeable lens 3 has been attached. Also, when the lens is fully attached, the lock pin 42 enters the lock pin receiving part 43, and the switch 28 (Figure 1), which is linked to the lock pin 42, is turned on. When the body-side control unit 23 detects that the signal level of the LDET(B) terminal has become low and that the switch 28 has been turned on, it starts supplying power to the V33(B) terminal to the power supply unit 26, that is, it supplies the power supply voltage to the circuit system. Note that the camera body 2 does not necessarily have to be equipped with a switch 28. If there is no switch 28, the power supply unit 26 should start supplying power to the V33(B) terminal when it detects that the signal level of the LDET(B) terminal has become low.

[0066] When power is supplied to the V33(B) terminal, the power supply voltage 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. The operating lens-side control unit 33 then permits initial communication with the body-side control unit 23 via command 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 power supply to the VBAT(L) terminal from the lens-side control unit 33. When the signal requesting power supply to the VBAT(L) terminal is transmitted from the lens-side control unit 33 to the body-side control unit 23, the body-side control unit 23 supplies power supply voltage to the VBAT(B) terminal, and initialization processing is performed between the camera body 2 and the interchangeable lens 3. During initialization processing, information necessary for various operations of the camera system 1, such as shooting and focusing operations, is exchanged between the camera body 2 and the interchangeable lens 3, and the lens position of the interchangeable lens is moved to the reference position.

[0067] When the lens is fully mounted, if the user presses the unillustrated unlock button on the camera body, the lock pin 42 retracts from the lock pin receiver 43. This allows the relative position between the body-side mount 21 and the lens-side mount 31 to be changed. When the user presses the unillustrated unlock button, the body-side control unit 23 turns off a switch 28 linked to the unlock button, stopping the power supply to the VBAT(B) terminal and V33(B) terminal of the power supply unit 26. From this state, if the interchangeable lens 3 is rotated in the opposite direction to the mounting direction 44 shown in Figures 5 and 6, the multiple lens-side terminals will come into contact with the multiple body-side terminals in the reverse order described above.

[0068] It is not necessary to stop the power supply in conjunction with the operation of the unlock button. In this case, the body-side control unit 23 stops the power supply to the VBAT(B) terminal and V33(B) terminal when it detects that the LDET(L) terminal and LDET(B) terminal have separated due to rotation in the opposite direction to the mounting direction 44 of the interchangeable lens 3, and that the signal level of the LDET(B) terminal has changed from a low level to a high level. This reduces the number of parts in the camera system 1. Alternatively, the power supply to the VBAT(B) terminal and V33(B) terminal may be stopped when both the unlock button is pressed and the signal level of the LDET(B) terminal has changed from a low level to a high level. Alternatively, when the unlock button is pressed or the signal level of the LDET(B) terminal changes from a low level to a high level, the body-side control unit 23 may stop supplying power to the VBAT(B) terminal and V33(B) terminal to the power supply unit 26.

[0069] As explained above, during the attachment and removal of interchangeable lenses from the camera body (while attached), the lens-side terminals may come into contact with body-side terminals other than the terminals they should be corresponding to when attachment is complete. It is desirable that the arrangement of the lens-side terminals and body-side terminals minimizes problems caused by this contact during attachment and removal.

[0070] (Terminal placement designed to minimize noise) In this embodiment, the LDET(B) terminal is positioned at the very front of the multiple body-side terminals in the direction of lens mounting (arrow 44 in Figure 5(a)). That is, as described above, the LDET(B) terminal is located at the leftmost position of the group of body-side terminals in Figure 5(a). Similarly, the LDET(L) terminal is also positioned at the very front of the multiple lens-side terminals in the direction of lens mounting (arrow 44 in Figure 6). That is, as described above, the LDET(L) terminal is located at the rightmost position of the group of lens-side terminals in Figure 6. Therefore, the LDET(B) terminal does not come into contact with any other lens-side terminals until the lens mounting is complete. Consequently, the signal level of the LDET(B) terminal will not mistakenly become low during the lens mounting process, and the lens mounting will not be incorrectly recognized.

[0071] In this embodiment, the VBAT(B) terminal is positioned next to the LDET(B) terminal, that is, second from the front in the mounting direction. The VBAT(L) terminal is positioned next to the LDET(L) terminal, that is, second from the front in the mounting direction. This arrangement is to reduce the number of lens-side terminals that the VBAT(B) terminal on the camera body side comes into contact with during the lens mounting process. Since the power supply voltage of the drive system applied to the VBAT(B) terminal is higher than that of the other terminals, if the VBAT(B) terminal comes into contact with a terminal other than the VBAT(L) terminal under circumstances where a high voltage is accidentally applied to the VBAT(B) terminal due to a malfunction of the camera system 1, this high voltage may place an unexpected load on the electrical circuit inside the interchangeable lens. In this embodiment, since the VBAT(B) terminal is located next to the LDET(B) terminal, during the mounting of the interchangeable lens 3, the VBAT(B) terminal comes into contact with only the LDET(L) terminal among the multiple lens-side terminals. As shown in Figure 2, the LDET(L) terminal is grounded via resistor R3, so even if a high voltage is applied from the VBAT(B) terminal, it will not affect the camera system 1.

[0072] In this embodiment, the PGND(B) terminal, which is at ground potential, is positioned next to the VBAT(B) terminal, i.e., third from the leading edge in the mounting direction. The PGND(L) terminal is positioned next to the VBAT(L) terminal, i.e., third from the leading edge in the mounting direction. The capacitor C1 connected to the VBAT(L) terminal stores charge from the high voltage supplied from the VBAT(B) terminal. When the interchangeable lens 3 is rotated in the removal direction, the VBAT(L) terminal first contacts the PGND(B) terminal. The charge stored in the capacitor C1 is quickly discharged from the PGND(B) terminal, which is at ground potential, and does not affect other circuits of the camera system 1.

[0073] In this embodiment, the V33(B) terminal is positioned next to the PGND(B) terminal, i.e., fourth from the front in the mounting direction, and the GND(B) terminal is positioned next to it, i.e., fifth from the front. The V33(L) terminal is positioned next to the PGND(L) terminal, i.e., fourth from the front in the mounting direction, and the GND(L) terminal is positioned next to it, i.e., fifth from the front. The capacitor C2 connected to the V33(L) terminal stores charge from the voltage supplied from the V33(B) terminal. When the interchangeable lens 3 is rotated in the removal direction, the V33(L) terminal first contacts the GND(B) terminal. The charge stored in the capacitor C2 is quickly discharged from the GND(B) terminal, which is at ground potential, and does not affect other circuits of the camera system 1.

[0074] The RDY(B) terminal is placed next to the GND(B) terminal, i.e., the 6th terminal from the front, the DATAB(B) terminal is placed next to it, i.e., the 7th terminal from the front, the CLK(B) terminal is placed next to it, i.e., the 8th terminal from the front, the DATAL(B) terminal is placed next to it, i.e., the 9th terminal from the front, the HCLK(B) terminal is placed next to it, i.e., the 10th terminal from the front, and the HDATA(B) terminal is placed next to it, at the very end.

[0075] The RDY(L) terminal is placed next to the GND(L) terminal, i.e., the 6th terminal from the front, the DATAB(L) terminal is placed next to it, i.e., the 7th terminal from the front, the CLK(L) terminal is placed next to it, i.e., the 8th terminal from the front, the DATAL(L) terminal is placed next to it, i.e., the 9th terminal from the front, the HCLK(L) terminal is placed next to it, i.e., the 10th terminal from the front, and the HDATA(L) terminal is placed next to it, at the very end.

[0076] Next, we will describe the effects of noise on the communication lines, which consist of each body-side terminal and each lens-side terminal. Hotline communication is a type of communication in which information (lens data) is unilaterally transmitted to the body after communication has started, and it is performed at a high frequency (repeated in very short cycles). During hotline communication, a clock signal (H clock signal) is sent from the HCLK(L) terminal to the HCLK(B) terminal. Since the clock signal is a signal that repeats between high and low levels in a short cycle, it can be a major noise source for other signals. Furthermore, since the clock signal transmitted from the HCLK(L) terminal to the HCLK(B) terminal is a signal output from interchangeable lens 3, even if noise is mistakenly superimposed on that clock signal, the camera body 2 cannot recognize that noise. Thus, the clock signal (H clock signal) flowing through the HCLK terminal may be a noise source, or noise may be superimposed on the clock signal (H clock signal), which may cause malfunctions in the camera system 1. Examples of malfunctions include incorrect detection of interchangeable lens attachment or incorrect determination of whether command communication is possible or not.

[0077] In this embodiment, the HCLK terminal is positioned away from the VBAT terminal, which is subjected to high voltage. The voltage and current of the VBAT terminal that drives the drive unit 37 of the interchangeable lens 3 fluctuate depending on the driving state of the drive unit 37, so fluctuations in the voltage and current of the VBAT terminal can become noise for other terminals. Therefore, by separating the VBAT terminal from the HCLK terminal, it is possible to suppress the effect of noise caused by fluctuations in the voltage and current of the VBAT terminal on the clock signal (H clock signal). This suppresses noise from being superimposed on the clock signal (H clock signal). The RDY terminal is used to indicate whether command communication is possible or not. The HCLK terminal, which can be a source of noise, is positioned away from the RDY terminal. Therefore, noise from the clock signal (H clock signal) can be suppressed from affecting the signal at the RDY terminal.

[0078] Furthermore, the HDATA and DATAL terminals are positioned on either side of the HCLK terminal. This arrangement minimizes the impact of noise from the HCLK terminal on terminals other than the HDATA and DATAL terminals. The signals flowing through the HDATA and DATAL terminals fluctuate less than the clock signal (H clock signal). Therefore, the impact of fluctuations in the clock signal (H clock signal) on terminals other than the HDATA and DATAL terminals is suppressed.

[0079] Next, as mentioned above, command data communication is a bidirectional communication method that sends and receives information between the body and the interchangeable lens. During command data communication, a clock signal (C clock signal) is sent from the CLK(B) terminal to the CLK(L) terminal. The clock signal transmitted at the CLK terminal can also be a source of noise for the same reasons mentioned earlier. Furthermore, if noise is superimposed on the clock signal (C clock signal), abnormalities will occur in command communication. Therefore, in this embodiment, the CLK terminal is positioned away from the VBAT terminal, which is subjected to high voltage. The voltage and current of the VBAT terminal that drives the drive unit 37 of the interchangeable lens 3 fluctuate depending on the driving state of the drive unit 37, so fluctuations in the voltage and current of the VBAT terminal can become noise for other terminals. Therefore, by separating the VBAT terminal from the CLK terminal, it is possible to suppress the effect of noise from the VBAT terminal on the clock signal (C clock signal). In other words, it is possible to suppress noise superimposed on the clock signal (C clock signal). Furthermore, the CLK terminal was positioned separately from the RDY terminal, which is used to indicate whether command communication is permitted or not.

[0080] Furthermore, if the HCLK terminal and the CLK terminal are placed adjacent to each other, one clock signal can affect the other clock signal, potentially becoming a noise source. In this embodiment, the DATAL terminal is placed between the CLK terminal and the HCLK terminal. Also, the DATAB terminal is placed between the CLK terminal and the RDY terminal. In other words, the DATAL terminal and the DATAB terminal are placed on both sides of the CLK terminal. This arrangement suppresses the impact of noise originating from the CLK terminal on the camera system. This is because the signals flowing through the DATAL terminal and the DATAB terminal fluctuate less than the clock signal (C clock signal), thus preventing fluctuations in the clock signal (C clock signal) from affecting terminals other than the DATAL terminal and the DATAB terminal. Placing the DATAL terminal between the CLK terminal and the HCLK terminal reduces the influence of fluctuations in the CLK terminal's clock signal (C clock signal) and the HCLK terminal's clock signal (H clock signal) on the DATAL terminal, as the signal flowing through the DATAL terminal fluctuates less than the clock signal of the CLK terminal (C clock signal) and the clock signal of the HCLK terminal (H clock signal).

[0081] As mentioned above, the level of the RDY terminal must be determined in order to perform command data communication. In other words, the signal level of the RDY terminal indicates whether command data can be communicated, so noise has a significant impact on the shooting operation. Now, consider the case where the body-side control unit 23 mistakenly recognizes that command data can be communicated due to noise, even though it is not possible to communicate command data. In this case, the lens-side control unit 33 cannot receive the command data, but the body-side control unit 23 transmits the command data, and the body-side control unit 23 mistakenly recognizes that control will be performed on the interchangeable lens according to that command data. However, since the lens-side control unit 33 cannot accept the command data, control will not be performed according to the mistakenly transmitted command data. Therefore, the operation of the camera system 1 will be impaired. For this reason, it is necessary to prevent noise from being superimposed on the signal of the RDY terminal. In order to prevent noise from being superimposed on the signal of the RDY terminal, it is desirable to place terminals on both sides of the RDY terminal that carry relatively stable signals, that is, signals with little change in signal level per unit time. In this embodiment, the GND terminal and DATAB terminal are placed on both sides of the RDY terminal. The GND terminal is stable because it is at ground potential, and the DATAB terminal also carries a more stable signal compared to the CLK and HCLK terminals. This approach helps to suppress the noise affecting the signal at the RDY terminal.

[0082] Next, the power supplied from the VBAT(B) terminal to the VBAT(L) terminal (the power supply voltage of the drive system) is used to drive the actuator (e.g., a stepping motor) of the drive unit 37 of the interchangeable lens 3. Therefore, the current flowing through the VBAT terminal fluctuates significantly depending on whether the actuator is driven or not. Such current fluctuations become a source of noise for signals flowing to other terminals. In this embodiment, the VBAT terminal is positioned away from the RDY terminal, DATAB terminal, CLK terminal, DATAL terminal used for command data communication, and the HCLK terminal and HDATA terminal used for hotline communication. Furthermore, the GND terminal, V33 terminal, and PGND terminal are placed between the VBAT terminal and the terminals used for these communications. Of these, the GND terminal and PGND terminal in particular are at ground potential, so the influence of noise can be suppressed. As a result, the influence of noise caused by fluctuations in the current flowing through the VBAT terminal on data communication is suppressed.

[0083] Here's a summary of the terminal arrangement that takes noise into consideration, as explained above. The RDY terminal is positioned away from both the VBAT and HCLK terminals, which are sources of noise. This minimizes the impact of noise on the RDY terminal, which is used to indicate whether command communication is possible or not. The HCLK terminal, which is a source of noise, is sandwiched between the HDATA and DATAL terminals, and the CLK terminal is sandwiched between the DATAL and DATAB terminals. In other words, the terminals are arranged in the following order from the rear end in the mounting direction: HDATA terminal, HCLK terminal, DATAL terminal, CLK terminal, and DATAB terminal. This suppresses the influence of noise caused by the clock signal on terminals such as the RDY terminal. Furthermore, considering the effects of noise, the terminals for power supply and the terminals used for communication were arranged separately with the RDY terminal in between. More specifically, the terminals for power supply, namely the VBAT terminal, PGND terminal, V33 terminal, and GND terminal, are arranged in order from the front end in the mounting direction, with the RDY terminal in between. The terminals used for communication, namely the DATAB terminal, CLK terminal, DATAL terminal, HCLK terminal, and HDATA terminal, are arranged in order from the front end in the mounting direction, with the RDY terminal in between. This reduces the influence of the power supply terminals, such as the VBAT terminal, on the terminals used for communication. It also reduces the influence of noise from the power supply terminals, such as the VBAT terminal, and the communication terminals, such as the HCLK terminal and CLK terminal, on the RDY terminal.

[0084] The HCLK terminal, which receives the clock signal (H clock signal) used for hotline communication, and the CLK terminal, which receives the clock signal (C clock signal) used for command data communication, are positioned further apart from the VBAT terminal than the CLK terminal. This is because, although the clock signal (C clock signal) sent to the interchangeable lens via the CLK terminal is output by the body-side control unit 23 via the body-side communication unit 24, if noise is superimposed on the clock signal (H clock signal) sent from the interchangeable lens to the camera body via the lens-side communication unit 34 and the HCLK(L) terminal, the body-side control unit 23 will misinterpret it. Therefore, the noise superimposed on the clock signal (H clock signal) at the HCLK terminal has a greater impact on the camera system 1. The HCLK terminal is positioned further away from the VBAT terminal than the GND terminal. Furthermore, a PGND terminal is placed between the GND terminal and the VBAT terminal. This shields the HCLK terminal, to which the clock signal (H clock signal) used for hotline communication is sent, from noise originating from the VBAT terminal. The CLK terminal is positioned further away from the VBAT terminal than the GND terminal. Furthermore, a PGND terminal is placed between the GND terminal and the VBAT terminal. This shields the CLK terminal, to which the clock signal (C clock signal) used for command data communication is sent, from noise originating from the VBAT terminal.

[0085] (Terminal arrangement considering wear) The following describes the contact of each terminal when attaching or detaching the interchangeable lens 3 to the camera body 2. When attaching interchangeable lens 3 to camera body 2, the body-side terminals successively come into contact with the lens-side terminals. The same occurs when removing interchangeable lens 3 from camera body 2. In other words, the body-side terminals, which are pins protruding from the body-side terminal holding part 22, and the lens-side terminals, which are exposed conductive contact surfaces, are rubbed against each other one after another. Because multiple interchangeable lenses are attached to and detached from a single camera body, the body-side terminals are more prone to wear than the lens-side terminals. In particular, the body-side terminals located towards the rear end in the direction in which interchangeable lens 3 is attached are rubbed against more lens-side terminals and experience more friction. Therefore, the tips of the pins of body-side terminals located towards the rear end are more prone to wear than those located towards the front end. Wear on the body-side terminals affects the contact with the lens-side terminals, which may lead to unstable data communication. In this embodiment, the LDET(B) terminal is positioned at the very front in the mounting direction, resulting in minimal wear on the LDET(B) terminal. This ensures good contact between the LDET(B) terminal and the LDET(L) terminal, reducing the possibility of false detection of the attachment or detachment of the interchangeable lens 3.

[0086] As mentioned above, in this embodiment, in order to suppress the influence of noise on communication, the CLK(B) terminal and HCLK(B) terminal are positioned away from the VBAT(B) terminal. In other words, the VBAT(B) terminal is positioned second from the front end in the mounting direction, and the CLK(B) terminal and HCLK(B) terminal are positioned at the rear end, away from the VBAT(B) terminal. Consequently, the CLK(B) terminal and HCLK(B) terminal experience more wear than the LDET(B) terminal and VBAT(B) terminal. In this embodiment, the CLK(B) terminal and HCLK(B) terminal are positioned right next to the first claw portion 29a on the body side. That is, the CLK(B) terminal and HCLK(B) terminal are positioned closer to the inner edge, which is the inner circumference edge of the first claw portion 29a on the body side, than the VBAT(B) terminal. In other words, the distance between the CLK(B) terminal and the inner edge of the body-side first claw portion 29a is shorter than the distance between the VBAT(B) terminal and the inner edge of the body-side first claw portion 29a, and the distance between the HCLK(B) terminal and the inner edge of the body-side first claw portion 29a is shorter than the distance between the VBAT(B) terminal and the inner edge of the body-side first claw portion 29a. As described above, there is a first leaf spring 41a on the back side of the body-side first claw portion 29a, and the first leaf spring 41a presses the lens-side first claw portion 39a in the +Z direction (Figure 1). From the perspective of the first leaf spring 41a, the distance between the CLK(B) terminal and the first leaf spring 41a, and the distance between the HCLK(B) terminal and the first leaf spring 41a are both shorter than the distance between the VBAT(B) terminal and the first leaf spring 41a. Furthermore, the LDET(B) terminal is the same as the VBAT(B) terminal, and the distance between the CLK(B) terminal and the first leaf spring 41a, and the distance between the HCLK(B) terminal and the first leaf spring 41a are both shorter than the distance between the LDET(B) terminal and the first leaf spring 41a. In this way, the CLK(B) terminal and the HCLK(B) terminal are pressed more firmly against the lens-side terminal than the VBAT(B) terminal and the LDET(B) terminal.

[0087] On the lens side, the CLK(L) terminal and HCLK(L) terminal are positioned closer to the inner edge of the first claw portion 39a on the lens side than the VBAT(L) terminal. In other words, the distance between the CLK(L) terminal and the inner edge of the first claw portion 39a on the lens side is shorter than the distance between the VBAT(L) terminal and the inner edge of the first claw portion 39a on the lens side, and the distance between the HCLK(L) terminal and the inner edge of the first claw portion 39a on the lens side is shorter than the distance between the VBAT(L) terminal and the inner edge of the first claw portion 39a on the lens side. Therefore, when the mounting is complete, the CLK(L) terminal and HCLK(L) terminal located next to the first claw portion 39a on the lens side are pressed against the corresponding body-side terminals by the first leaf spring 41a. Furthermore, the LDET(L) terminal is similar to the VBAT(L) terminal, and in the fully mounted state, the distance between the CLK(L) terminal and the first leaf spring 41a, and the distance between the HCLK(L) terminal and the first leaf spring 41a are both shorter than the distance between the LDET(L) terminal and the first leaf spring 41a. In this way, the CLK(L) terminal and HCLK(L) terminal exert a stronger pressing force against the body-side terminal than the LDET(L) terminal in the fully mounted state. This ensures that good contact is maintained even if the CLK(B) terminal and HCLK(B) terminal wear down, resulting in stable clock signals and stable data communication. Also, for example, even if the camera body 2 or interchangeable lens 3 is subjected to impact while the fully mounted state is maintained, the contact between the CLK(B) terminal and the CLK(L) terminal, and the contact between the HCLK(B) terminal and the HCLK(L) terminal are maintained.

[0088] Even if a portion of the lens-side first claw portion 39a is cut out, the entire area, including the protruding portion and the cut-out portion, located in the region facing the body-side first claw portion 29a, is considered the lens-side first claw portion. The cut-out can be made by dividing the lens-side claw portion into two or more parts in the circumferential direction, by cutting out a portion of the lens-side claw portion, or by cutting out at least a portion of the lens-side claw portion so that its radial length is shortened. The circumferential length of the lens-side claw portion may also be changed within the range that passes through the corresponding body-side insertion / removal portion. The same applies to the lens-side second claw portion 39b, lens-side third claw portion 39c, and lens-side fourth claw portion 39d. Furthermore, the radial thickness of the cylindrical portion can be changed as appropriate, and it may have a shape in which at least a portion protrudes inward from the cylindrical portion of this embodiment.

[0089] As described above, the CLK(B) terminal and HCLK(B) terminal experience more wear than the LDET(B) terminal and VBAT(B) terminal. In this embodiment, the CLK(B) terminal and HCLK(B) terminal are positioned very close to the body-side first claw portion 29a. That is, the CLK(B) terminal and HCLK(B) terminal are positioned closer to the inner edge of the body-side first claw portion 29a than the LDET(B) terminal and VBAT(B) terminal. In other words, the distance between the CLK(B) terminal and the inner edge of the body-side first claw portion 29a is shorter than the distance between the LDET(B) terminal and VBAT(B) terminal and the inner edge of the body-side first claw portion 29a, and the distance between the HCLK(B) terminal and the inner edge of the body-side first claw portion 29a is shorter than the distance between the LDET(B) terminal and VBAT(B) terminal and the inner edge of the body-side first claw portion 29a. As described above, there is a first leaf spring 41a on the back side of the first claw portion 29a on the body side, and the first leaf spring 41a presses the first claw portion 39a on the lens side in the +Z direction (Figure 1). From the perspective of the first leaf spring 41a, the distance between the CLK(B) terminal and the first leaf spring 41a, and the distance between the HCLK(B) terminal and the first leaf spring 41a are both shorter than the distance between the LDET(B) terminal and the VBAT(B) terminal and the first leaf spring 41a.

[0090] On the lens side, the CLK(L) terminal and HCLK(L) terminal are positioned closer to the inner edge of the first claw portion 39a on the lens side than the LDET(L) terminal and VBAT(L) terminal. In other words, the distance between the CLK(L) terminal and the inner edge of the first claw portion 39a on the lens side is shorter than the distance between the LDET(L) terminal and VBAT(L) terminal and the inner edge of the first claw portion 39a on the lens side, and the distance between the HCLK(L) terminal and the inner edge of the first claw portion 39a on the lens side is shorter than the distance between the LDET(L) terminal and VBAT(L) terminal and the inner edge of the first claw portion 39a on the lens side. Therefore, the CLK(L) terminal and HCLK(L) terminal located near the first claw portion 39a on the lens side are pressed against the corresponding body-side terminals by the first leaf spring 41a. As a result, the CLK(B) and HCLK(B) terminals are pressed more firmly against the lens-side terminals than the LDET(B) and VBAT(B) terminals. This ensures that good contact is maintained even if the CLK(B) and HCLK(B) terminals wear down, enabling stable communication. Furthermore, even if the camera body 2 or interchangeable lens 3 is subjected to impact while the lens is mounted, the contact between the CLK(B) and HCLK(B) terminals and the lens-side terminals is maintained.

[0091] In this embodiment, the CLK(B) terminal and the HCLK(B) terminal are also close to the body-side fourth claw portion 29d. That is, the CLK(B) terminal and the HCLK(B) terminal are positioned closer to the body-side fourth claw portion 29d than the VBAT(B) terminal and the LDET(B) terminal. In other words, the distance between the CLK(B) terminal and the body-side fourth claw portion 29d is shorter than the distance between the VBAT(B) terminal or the LDET(B) terminal and the body-side fourth claw portion 29d, and the distance between the HCLK(B) terminal and the body-side fourth claw portion 29d is shorter than the distance between the VBAT(B) terminal or the LDET(B) terminal and the body-side fourth claw portion 29d. As described above, there is a fourth leaf spring 41d on the back side of the body-side fourth claw portion 29d, and the fourth leaf spring 41d presses the lens-side fourth claw portion 39d in the +Z direction (Figure 1). Therefore, the CLK(B) terminal and HCLK(B) terminal, located near the fourth claw portion 39d on the lens side, are pressed more firmly against the lens-side terminal by the first leaf spring 41a and the fourth leaf spring 41d than the VBAT(B) terminal and LDET(B) terminal.

[0092] The distance between the CLK(B) terminal and the body-side first claw portion 29a (the same applies to the body-side fourth claw portion 29d, but this will be omitted below) is the straight-line distance between one end of the body-side first claw portion 29a and the CLK(B) terminal, and may also be defined as the straight-line distance between the other end of the body-side first claw portion 29a and the CLK(B) terminal. Alternatively, the distance between the CLK(B) terminal and the body-side first claw portion 29a may be defined as the straight-line distance between the midpoint of the body-side first claw portion 29a in the circumferential direction of the body-side mount 21 and the CLK(B) terminal. The distance between other body-side terminals such as the HCLK(B) terminal, VBAT(B) terminal, and LDET(B) terminal and the body-side first claw portion 29a is also a straight-line distance. The distance between the first leaf spring 41a (fourth leaf spring 41d) and the body-side terminal is also a straight-line distance.

[0093] The distance between the CLK(B) terminal and the body-side first claw portion 29a (the same applies to the body-side fourth claw portion 29d, but this is omitted below) may be defined as the arc-shaped distance between one end of the body-side first claw portion 29a and the CLK(B) terminal in the circumferential direction of the body-side mount 21, or as the arc-shaped distance between the other end of the body-side first claw portion 29a and the CLK(B) terminal. Alternatively, the distance between the CLK(B) terminal and the body-side first claw portion 29a may be defined as the arc-shaped distance between the midpoint of the body-side first claw portion 29a in the circumferential direction of the body-side mount 21 and the CLK(B) terminal. The distance between other body-side terminals such as the HCLK(B) terminal, VBAT(B) terminal, and LDET(B) terminal and the body-side first claw portion 29a is also an arc-shaped distance. The distance between the first leaf spring 41a (fourth leaf spring 41d) and the body-side terminal is also an arc-shaped distance.

[0094] The above describes the camera body 2, but the same applies to the interchangeable lens 3. In this embodiment, the CLK(L) terminal and HCLK(L) terminal are positioned very close to the lens-side first claw portion 39a. That is, the CLK(L) terminal and HCLK(L) terminal are positioned closer to the lens-side first claw portion 39a than the VBAT(L) terminal and LDET(L) terminal. In other words, the distance between the CLK(L) terminal and the lens-side first claw portion 39a is shorter than the distance between the VBAT(L) terminal or LDET(L) terminal and the lens-side first claw portion 39a, and the distance between the HCLK(L) terminal and the lens-side first claw portion 39a is shorter than the distance between the VBAT(L) terminal or LDET(L) terminal and the lens-side first claw portion 39a. The lens-side first claw portion 39a is pressed in the +Z direction (Figure 1) by the body-side first leaf spring 41a. Therefore, as described above, the CLK(L) terminal and HCLK(L) terminal, which are located near the first claw portion 39a on the lens side, are pressed more firmly against the body-side terminal by the first leaf spring 41a than the VBAT(L) terminal or LDET(L) terminal.

[0095] In this embodiment, as shown in Figure 5(a), the CLK(B) terminal and the HCLK(B) terminal are positioned within a sector (within an angle of 50) formed by the center position of the opening of the mount 21 (i.e., the position of the optical axis O of the interchangeable lens 3) and the arc-shaped first claw portion 29a on the body side. Alternatively, the CLK(B) terminal and the HCLK(B) terminal are positioned within a triangular region formed by the center position of the opening of the mount 21 (i.e., the position of the optical axis O of the interchangeable lens 3) and both ends on the inner circumference of the first claw portion 29a on the body side. Therefore, the first claw portion 29a on the body side does not lie on the extension of the dashed line 51 connecting the center position of the opening of the mount 21 and the LDET(B) terminal, but the first claw portion 29a on the body side does lie on the extension of the dashed line 52 connecting the center position of the opening of the mount 21 and the HCLK(B) terminal, and the first claw portion 29a on the body side does lie on the extension of the dashed line 53 connecting the center position of the opening of the mount 21 and the CLK(B) terminal. As a result, when the mounting is complete, the CLK(B) terminal and HCLK(B) terminal are pressed more firmly against the corresponding lens-side terminal than the LDET(B) terminal.

[0096] As shown in Figure 6, the CLK(L) terminal and the HCLK(L) terminal are positioned within a sector (within an angle of 60 degrees) formed by the center position of the aperture of the mount 31 (i.e., the position of the optical axis O of the interchangeable lens 3) and the arc-shaped first claw portion 39a on the lens side. Alternatively, the CLK(L) terminal and the HCLK(L) terminal are positioned within a triangular region formed by the center position of the aperture of the mount 31 (i.e., the position of the optical axis O of the interchangeable lens 3) and both ends on the outer circumference of the first claw portion 39a on the lens side. Therefore, the first claw portion 39a on the lens side does not lie on the extension of the dashed line 61 connecting the center position of the aperture of the mount 31 and the LDET(L) terminal, but the first claw portion 39a on the lens side does lie on the extension of the dashed line 62 connecting the center position of the aperture of the mount 31 and the HCLK(L) terminal, and the first claw portion 39a on the lens side does lie on the extension of the dashed line 63 connecting the center position of the aperture of the mount 31 and the CLK(L) terminal. As a result, when the lens is fully attached, the CLK(L) terminal and HCLK(L) terminal make more stable contact with the corresponding body-side terminal than the LDET(L) terminal. In other words, the CLK(L) terminal and HCLK(L) terminal exert a stronger force on the body-side terminal than the LDET(L) terminal. Therefore, even if the tips of the CLK(B) terminal and HCLK(B) terminal wear down, the communication of clock signals between the camera body 2 and the interchangeable lens 3 remains stable.

[0097] In this embodiment, we have described the CLK(B) terminal, CLK(L) terminal, HCLK(B) terminal, and HCLK(L) terminal, but the same applies to the other communication terminals, namely the HDA(B) terminal, HDA(L) terminal, DATAL(B) terminal, DATAL(L) terminal, DATAB(B) terminal, and DATAB(L) terminal. That is, the HDA(B) terminal, DATAL(B) terminal, and DATAB(B) terminal are positioned closer to the body-side first claw portion 29a and the first leaf spring 41a than the LDET(B) terminal and VBAT(B) terminal (the distance is shorter). As a result, the HDA(B) terminal, DATAL(B) terminal, and DATAB(B) terminal are pressed more firmly against the lens-side terminal than the VBAT(B) terminal and LDET(B) terminal, and can maintain good contact with the lens-side terminal. Furthermore, the HDATA(L), DATAL(L), and DATAB(L) terminals are positioned closer to the first claw portion 39a on the lens side than the LDET(L) and VBAT(L) terminals (the distance is shorter). As a result, the HDATA(L), DATAL(L), and DATAB(L) terminals are pressed more firmly against the body-side terminals than the VBAT(L) and LDET(L) terminals, maintaining good contact with the lens-side terminals.

[0098] (Second Embodiment) Next, the interchangeable lens 3A of the camera system 1 according to the second embodiment will be described. Figure 7 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3A according to the second embodiment. As shown in Figure 7, the lens-side terminal holder 32A of the interchangeable lens 3A according to the second embodiment has the following terminals, similar to the interchangeable lens 3 according to the first embodiment: LDET(L) terminal, VBAT(L) terminal, PGND(L) terminal, V33(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holder 32A of the interchangeable lens 3A according to the second embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0099] The interchangeable lens 3A according to the second embodiment is configured to synchronize data transmission and reception via command data communication using a method similar to, for example, a so-called asynchronous communication method. At the start of command data communication, the signal sequence received by the lens-side communication unit 34A from the body-side communication unit 24 via the DATAB(B) terminal and DATAB(L) terminal is constant. Therefore, the lens-side control unit 33A can identify the signal sequence received from the body-side communication unit 24 at the start of command data communication and determine the periodic timing and clock frequency necessary for synchronizing data transmission and reception via command data communication.

[0100] Similar to the operation of the interchangeable lens 3 according to the first embodiment described with reference to Figure 3, the lens-side control unit 33A of the interchangeable lens 3A according to the second embodiment uses the periodic timing and clock frequency determined by the method described above to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal. The interchangeable lens 3A according to the second embodiment may also include an ASIC (application-specific integrated circuit) having a dedicated circuit for determining the periodic timing and clock frequency necessary for synchronizing data transmission and reception via command data communication.

[0101] Furthermore, the lens-side terminal holding portion 32A of the interchangeable lens 3A according to the second embodiment has a configuration in which each terminal other than the CLK(L) terminal shown in the example in Figure 6 is arranged. That is, the lens-side terminal holding portion 32A of the interchangeable lens 3A has a configuration in which the terminals LDET(L), VBAT(L), PGND(L), V33(L), ​​GND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0102] (Third embodiment) Next, the interchangeable lens 3B of the camera system 1 according to the third embodiment will be described. Figure 8 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3B according to the third embodiment. As shown in Figure 8, the lens-side terminal holding portion 32B of the interchangeable lens 3B according to the third embodiment has the LDET(L) terminal, VBAT(L) terminal, PGND(L) terminal, V33(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holding portion 32B of the interchangeable lens 3B according to the third embodiment does not have the GND(L) terminal of the interchangeable lens 3 according to the first embodiment. Furthermore, the lens-side terminal holding portion 32B of the interchangeable lens 3B according to the third embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0103] Therefore, in the third embodiment, the interchangeable lens 3B has a PGND(L) terminal which is used as the ground potential of the power supply voltage of the drive system, and is also connected to various parts such as the lens-side control unit 33B, and is used as the ground potential of the power supply voltage of the circuit system. A bypass capacitor C2 is connected between the V33(L) terminal and the PGND(L) terminal.

[0104] Furthermore, the lens control unit 33B of the interchangeable lens 3B according to the third embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0105] Furthermore, the lens-side terminal holding portion 32B of the interchangeable lens 3B according to the third embodiment has a configuration in which terminals other than the GND(L) terminal and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32B of the interchangeable lens 3B has a configuration in which the terminals LDET(L), VBAT(L), PGND(L), V33(L), ​​RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0106] (Fourth embodiment) Next, the interchangeable lens 3C of the camera system 1 according to the fourth embodiment will be described. Figure 9 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3C according to the fourth embodiment. As shown in Figure 9, the lens-side terminal holding portion 32C of the interchangeable lens 3C according to the fourth embodiment has LDET(L) terminal, VBAT(L) terminal, V33(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holding portion 32C of the interchangeable lens 3C according to the fourth embodiment does not have the PGND(L) terminal of the interchangeable lens 3 according to the first embodiment. Furthermore, the lens-side terminal holding portion 32C of the interchangeable lens 3C according to the fourth embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0107] Therefore, in the fourth embodiment, the interchangeable lens 3C has a GND(L) terminal which is used as the ground potential (ground) of the power supply voltage of the circuit system, and is also connected to various parts such as the drive unit 37 and used as the ground potential (ground) of the power supply voltage of the drive system. A bypass capacitor C1 is connected between the VBAT(L) terminal and the GND(L) terminal, and a bypass capacitor C2 is connected between the V33(L) terminal and the GND(L) terminal.

[0108] Furthermore, the lens control unit 33C of the interchangeable lens 3C according to the fourth embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0109] Furthermore, the lens-side terminal holding portion 32C of the interchangeable lens 3C according to the fourth embodiment has a configuration in which terminals other than the PGND(L) terminal and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32C of the interchangeable lens 3C has a configuration in which the terminals LDET(L), VBAT(L), V33(L), ​​GND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0110] (Fifth embodiment) Next, the interchangeable lens 3D of the camera system 1 according to the fifth embodiment will be described. Figure 10 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3D according to the fifth embodiment. As shown in Figure 10, the lens-side terminal holder 32D of the interchangeable lens 3D according to the fifth embodiment has LDET(L) terminal, VBAT(L) terminal, PGND(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holder 32D of the interchangeable lens 3D according to the fifth embodiment does not have the V33(L) terminal of the interchangeable lens 3 according to the first embodiment, and power for supplying the lens-side control unit 33D, etc., is not supplied from the camera body 2. Furthermore, the lens-side terminal holding portion 32D of the interchangeable lens 3D according to the fifth embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0111] Therefore, the interchangeable lens 3D according to the fifth embodiment includes a DC / DC converter 50. The DC / DC converter 50 is, for example, a step-down voltage conversion circuit and is connected to the VBAT(L) terminal and the lens-side control unit 33D. The DC / DC converter 50 converts the power supply voltage supplied from the camera body 2 via the VBAT(L) terminal and supplies power to the lens-side control unit 33D, etc. A bypass capacitor C2 is connected between the power supply wiring from the DC / DC converter 50 to the lens-side control unit 33D, etc. and the GND(L) terminal.

[0112] Furthermore, the lens control unit 33D of the interchangeable lens 3D according to the fifth embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0113] Furthermore, the lens-side terminal holding portion 32D of the interchangeable lens 3D according to the fifth embodiment has a configuration in which terminals other than the V33(L) terminal and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32D of the interchangeable lens 3D has a configuration in which the terminals LDET(L), VBAT(L), PGND(L), GND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0114] (Sixth Embodiment) Next, the interchangeable lens 3E of the camera system 1 according to the sixth embodiment will be described. Figure 11 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3E according to the sixth embodiment. As shown in Figure 11, the lens-side terminal holding portion 32E of the interchangeable lens 3E according to the sixth embodiment has LDET(L) terminal, PGND(L) terminal, V33(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holding portion 32E of the interchangeable lens 3E according to the sixth embodiment does not have the VBAT(L) terminal of the interchangeable lens 3 according to the first embodiment, and power for the drive system to supply power to the drive unit 37, etc., is not supplied from the camera body 2. Furthermore, the lens-side terminal holding portion 32E of the interchangeable lens 3E according to the sixth embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0115] Therefore, the interchangeable lens 3E according to the sixth embodiment includes a DC / DC converter 51. The DC / DC converter 51 is, for example, a boost-type voltage conversion circuit and is connected to the V33(L) terminal and the drive unit 37. The DC / DC converter 51 converts the power supply voltage supplied from the camera body 2 via the V33(L) terminal and supplies power to the drive system circuit, such as the drive unit 37. A bypass capacitor C1 is connected between the wiring for power supply from the DC / DC converter 51 to the drive unit 37, etc., and the PGND(L) terminal.

[0116] Furthermore, the lens control unit 33E of the interchangeable lens 3E according to the sixth embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0117] Furthermore, the lens-side terminal holding portion 32E of the interchangeable lens 3E according to the sixth embodiment has a configuration in which all terminals other than the VBAT(L) terminal and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32D of the interchangeable lens 3D has a configuration in which the terminals LDET(L), PGND(L), V33(L), ​​GND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0118] (Seventh Embodiment) Next, the interchangeable lens 3F of the camera system 1 according to the seventh embodiment will be described. The configuration common to the first embodiment described above will not be explained. Figure 12 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3F according to the seventh embodiment. As shown in Figure 12, the lens-side terminal holder 32F of the interchangeable lens 3F according to the seventh embodiment has LDET(L) terminal, VBAT(L) terminal, PGND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holder 32F of the interchangeable lens 3F according to the seventh embodiment does not have the V33(L) terminal and GND(L) terminal of the interchangeable lens 3 according to the first embodiment, and power for supplying the lens-side control unit 33F and the like is not supplied from the camera body 2. Furthermore, the lens-side terminal holding portion 32F of the interchangeable lens 3F according to the seventh embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0119] Therefore, the interchangeable lens 3F according to the seventh embodiment includes a DC / DC converter 52. The DC / DC converter 52 is, for example, a step-down voltage conversion circuit and is connected to the VBAT(L) terminal and the lens-side control unit 33F. The DC / DC converter 52 converts the power supply voltage supplied from the camera body 2 via the VBAT(L) terminal and supplies power to the lens-side control unit 33F and the like.

[0120] Furthermore, in the seventh embodiment, the interchangeable lens 3F has a PGND(L) terminal which is used as the ground potential (ground) of the power supply voltage of the drive system, and is also connected to various parts such as the lens-side control unit 33F, and is used as the ground potential (ground) of the power supply voltage of the circuit system. A bypass capacitor C2 is connected between the wiring for power supply from the DC / DC converter 52 to the lens-side control unit 33F, etc., and the PGND(L) terminal.

[0121] Furthermore, the lens control unit 33F of the interchangeable lens 3F according to the seventh embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0122] Furthermore, the lens-side terminal holding portion 32F of the interchangeable lens 3F according to the seventh embodiment has a configuration in which terminals other than the V33(L) terminal, GND(L) terminal, and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32F of the interchangeable lens 3F has a configuration in which the terminals LDET(L), VBAT(L), PGND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0123] (Eighth embodiment) Next, the interchangeable lens 3G of the camera system 1 according to the eighth embodiment will be described. The configuration common to the first embodiment described above will not be explained. Figure 12 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3G according to the eighth embodiment. As shown in Figure 12, the lens-side terminal holder 32G of the interchangeable lens 3G according to the eighth embodiment has LDET(L) terminal, VBAT(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holder 32G of the interchangeable lens 3G according to the seventh embodiment does not have the PGND(L) terminal and V33(L) terminal of the interchangeable lens 3 according to the first embodiment, and power for supplying the lens-side control unit 33G, etc., is not supplied from the camera body 2. Furthermore, the lens-side terminal holding portion 32G of the interchangeable lens 3G according to the eighth embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0124] Therefore, the interchangeable lens 3G according to the eighth embodiment includes a DC / DC converter 53. The DC / DC converter 53 is, for example, a step-down voltage conversion circuit and is connected to the VBAT(L) terminal and the lens-side control unit 33G. The DC / DC converter 53 converts the power supply voltage supplied from the camera body 2 via the VBAT(L) terminal and supplies power to the lens-side control unit 33G and the like.

[0125] Furthermore, in the interchangeable lens 3G according to the eighth embodiment, the GND(L) terminal is used as the ground potential (ground) of the power supply voltage of the circuit system, and is also connected to various parts such as the drive unit 37, and is used as the ground potential (ground) of the power supply voltage of the drive system. A bypass capacitor C1 is connected between the VBAT(L) terminal and the GND(L) terminal, and a bypass capacitor C2 is connected between the power supply wiring from the DC / DC converter 53 to the lens-side control unit 33G etc. and the GND(L) terminal.

[0126] Furthermore, the lens control unit 33G of the interchangeable lens 3G according to the eighth embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0127] Furthermore, the lens-side terminal holding portion 32G of the interchangeable lens 3G according to the eighth embodiment has a configuration in which terminals other than the PGND(L) terminal, V33(L) terminal and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32G of the interchangeable lens 3G has a configuration in which the terminals LDET(L), VBAT(L), GND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0128] (Ninth Embodiment) Next, the interchangeable lens 3H of the camera system 1 according to the ninth embodiment will be described. The configuration common to the first embodiment described above will not be explained. Figure 14 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3H according to the ninth embodiment. As shown in Figure 14, the lens-side terminal holder 32H of the interchangeable lens 3H according to the ninth embodiment has the LDET(L) terminal, PGND(L) terminal, V33(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holder 32H of the interchangeable lens 3H according to the ninth embodiment does not have the VBAT(L) terminal and GND(L) terminal of the interchangeable lens 3 according to the first embodiment, and power for the drive system to supply power to the drive unit 37 and the like is not supplied from the camera body 2. Furthermore, the lens-side terminal holding portion 32H of the interchangeable lens 3H according to the ninth embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and the clock signal used for command data communication is not input from the camera body 2.

[0129] Therefore, the interchangeable lens 3H according to the ninth embodiment includes a DC / DC converter 54. The DC / DC converter 54 is, for example, a boost-type voltage conversion circuit and is connected to the V33(L) terminal and the drive unit 37. The DC / DC converter 54 converts the power supply voltage supplied from the camera body 2 via the V33(L) terminal and supplies power to the drive system circuits such as the drive unit 37.

[0130] Furthermore, in the interchangeable lens 3H according to the ninth embodiment, the PGND(L) terminal is used as the ground potential (ground) of the power supply voltage of the drive system, and is also connected to various parts such as the lens-side control unit 33H, and is used as the ground potential (ground) of the power supply voltage of the circuit system. A bypass capacitor C1 is connected between the wiring for power supply from the DC / DC converter 54 to the drive unit 37, etc., and the PGND(L) terminal.

[0131] Furthermore, the lens control unit 33H of the interchangeable lens 3H according to the ninth embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0132] Furthermore, the lens-side terminal holding portion 32H of the interchangeable lens 3H according to the ninth embodiment has a configuration in which terminals other than the VBAT(L) terminal, GND(L) terminal, and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32H of the interchangeable lens 3H has a configuration in which the terminals LDET(L), PGND(L), V33(L), ​​RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0133] (Tenth embodiment) Next, the interchangeable lens 3I of the camera system 1 according to the tenth embodiment will be described. The configuration common to the first embodiment described above will not be explained. Figure 15 is a schematic circuit diagram showing the electrical connection between the camera body 2 and the interchangeable lens 3I according to the tenth embodiment. As shown in Figure 15, the lens-side terminal holding portion 32I of the interchangeable lens 3I according to the tenth embodiment has the LDET(L) terminal, V33(L) terminal, GND(L) terminal, RDY(L) terminal, DATAB(L) terminal, DATAL(L) terminal, HCLK(L) terminal, and HDATA(L) terminal, similar to the interchangeable lens 3 according to the first embodiment. The functions and roles of these terminals are the same as those of the interchangeable lens 3 according to the first embodiment, so their explanation will be omitted. The lens-side terminal holding portion 32I of the interchangeable lens 3I according to the tenth embodiment does not have the VBAT(L) terminal and PGND(L) terminal of the interchangeable lens 3 according to the first embodiment, and power for the drive system to supply power to the drive unit 37 and the like is not supplied from the camera body 2. Furthermore, the lens-side terminal holding portion 32I of the interchangeable lens 3I according to the tenth embodiment does not have the CLK(L) terminal of the interchangeable lens 3 according to the first embodiment, and a clock signal used for command data communication is not input from the camera body 2.

[0134] Therefore, the interchangeable lens 3I according to the tenth embodiment includes a DC / DC converter 55. The DC / DC converter 55 is, for example, a boost-type voltage conversion circuit and is connected to the V33(L) terminal and the drive unit 37. The DC / DC converter 55 converts the power supply voltage supplied from the camera body 2 via the V33(L) terminal and supplies power to the drive system circuit, such as the drive unit 37.

[0135] Furthermore, in the tenth embodiment, the interchangeable lens 3I has a GND(L) terminal which is used as the ground potential (ground) of the power supply voltage of the circuit system, and is also connected to various parts such as the drive unit 37, and is used as the ground potential (ground) of the power supply voltage of the drive system. A bypass capacitor C1 is connected between the wiring for power supply from the DC / DC converter 55 to the drive unit 37, etc., and the GND(L) terminal.

[0136] Furthermore, the lens control unit 33I of the interchangeable lens 3I according to the tenth embodiment, similar to the interchangeable lens 3A according to the second embodiment described above, uses the periodic timing and clock frequency obtained by identifying the signal sequence received from the body-side communication unit 24 at the start of command data communication to receive body-side command signals from the body-side communication unit 34 via the DATAB(L) terminal and transmit lens-side data signals to the body-side communication unit 34 via the DATAL(L) terminal.

[0137] Furthermore, the lens-side terminal holding portion 32I of the interchangeable lens 3I according to the tenth embodiment has a configuration in which terminals other than the VBAT(L) terminal, PGND(L) terminal and CLK(L) terminal shown in the example in Figure 6 are arranged. That is, the lens-side terminal holding portion 32H of the interchangeable lens 3H has a configuration in which the terminals LDET(L), V33(L), ​​GND(L), RDY(L), DATAB(L), DATAL(L), HCLK(L), and HDATA(L) are arranged.

[0138] In the second to tenth embodiments, as in the first embodiment, the following effects are achieved in suppressing the influence of various types of noise. The RDY terminal is positioned away from both the VBAT terminal and the HCLK terminal, which are sources of noise. This suppresses the influence of noise on the RDY terminal, which is used to indicate whether command communication is possible or not. Furthermore, the HCLK terminal, which is a source of noise, was sandwiched between the HDATA and DATAL terminals, and the CLK terminal was sandwiched between the DATAL and DATAB terminals. In other words, the terminals were arranged in the order of HDATA, HCLK, DATAL, and DATAB terminals from the rear end in the mounting direction. This suppresses the influence of noise caused by the clock signal on terminals such as the RDY terminal. Furthermore, considering the effects of noise, the terminals for power supply and the terminals used for communication were arranged separately, with the RDY terminal in between. More specifically, the terminals for power supply, namely the VBAT terminal, PGND terminal, V33 terminal, and GND terminal, are arranged in order from the front end in the mounting direction, with the RDY terminal in between. The terminals used for communication, namely the DATAB terminal, DATAL terminal, HCLK terminal, and HDATA terminal, are arranged in order from the front end in the mounting direction, with the RDY terminal in between. This reduces the influence of the power supply terminals, such as the VBAT terminal, on the terminals used for communication. It also reduces the influence of noise from the power supply terminals, such as the VBAT terminal, and the communication terminals, such as the HCLK terminal, on the RDY terminal.

[0139] The HCLK terminal is positioned further away from the VBAT terminal than the GND terminal. Furthermore, a PGND terminal is placed between the GND terminal and the VBAT terminal. This shields the HCLK terminal, to which the clock signal (H clock signal) used for hotline communication is sent, from noise originating from the VBAT terminal.

[0140] The following modifications are also possible, and one or more of these modifications can be combined with the embodiments described above. (Variation 1) Either the terminal used for command data communication or hotline communication may also be equipped with a function to transmit a power-on signal from the interchangeable lens 3 to the camera body 2. For example, the interchangeable lens 3 may be equipped with a power switch function. Even when the interchangeable lens 3 is fully mounted and the camera system 1 is powered off, the power supply unit 26 supplies power from the V33(B) terminal to the lens-side control unit 33 of the interchangeable lens 3. When the power switch of the interchangeable lens 3 is operated, the lens-side control unit 33 outputs a power-on signal to the RDY(L) terminal, for example via the lens-side communication unit 34. When the body-side control unit 23 detects the power-on signal via the RDY(B) terminal through the body-side communication unit 24, it transitions the camera system 1 from the power-off state to the power-on state, similar to when a power switch (not shown) provided on the camera body 2 is operated.

[0141] (Modification 2) In this embodiment, the DATAB(B) terminal is positioned on the leading end side of the CLK(B) terminal in the mounting direction, and the DATAL(B) terminal is positioned on the rear end side. However, the positions of the DATAB(B) and DATAL(B) terminals may be swapped. That is, the terminals may be arranged in the order of DATAL(B), CLK(B), and DATAB(B) terminals from the leading end side in the mounting direction.

[0142] Furthermore, regarding each terminal of the lens-side terminal group described in each of the embodiments described above, the LDET(L) terminal may be referred to as the detection terminal. The VBAT(L) terminal may be referred to as the power terminal or the first power terminal. The PGND(L) terminal may be referred to as the ground terminal or the first ground terminal. The V33(L) terminal may be referred to as the power terminal or the second power terminal. The GND(L) terminal may be referred to as the ground terminal or the second ground terminal. The RDY(L) terminal may be referred to as the ready terminal. The DATAB(L) terminal may be referred to as the data terminal or the first data terminal. The CLK(L) terminal may be referred to as the clock terminal or the first clock terminal. The DATAL(L) terminal may be referred to as the data terminal or the second data terminal. The HCLK(L) terminal may be referred to as the clock terminal or the second clock terminal. The HDATA(L) terminal may be referred to as the data terminal or the third data terminal.

[0143] In the above embodiment, interchangeable camera lenses were used as an example of accessories, but accessories are not limited to interchangeable lenses. For example, teleconverters, wide-angle converters, or extension rings that are attached between the camera body and the interchangeable lens to change the focal length of the interchangeable lens may also be used. Alternatively, the invention can be applied to mount adapters that allow accessories, including interchangeable lenses of other mount standards, to be attached to the camera body's mount standard. In other words, the invention can be applied to any accessory that is attached to the camera body's mount. In that case, the lens-side terminal group, lens-side claw portion 39, lens-side communication portion 34, etc. correspond to the accessory-side terminal group, accessory-side protrusion portion, accessory-side communication portion, etc. of each respective accessory. In the above embodiment, the accessory was described as being detachable from the camera body, but the camera body may be a mount adapter that allows interchangeable lenses of the above mount standard to be attached to a camera body with a different mount standard than the one described above, and the above-described accessory may be attached to that mount adapter. [Explanation of Symbols]

[0144] 1...Camera system, 2...Camera body, 3, 3A, 3B, 3C, 3D, 3E, 3F, 3G, 3H, 3I...Interchangeable lenses, 21...Body-side mount, 22...Body-side terminal retainer, 31...Lens-side mount, 32, 32A, 32B, 32C, 32D, 32E, 32F, 32G, 32H, 32I...Lens-side terminal retainer

Claims

[Claim 1] An accessory that can be attached to the camera body, A communication unit including a circuit that communicates with the camera body, A ready terminal used to indicate whether or not communication with the camera body via the communication unit is possible, A first data terminal to which a first data signal is input from the camera body to the communication unit, The camera body is provided with a second data terminal that outputs a second data signal from the communication unit, The camera body has a first clock terminal that outputs a clock signal from the communication unit, The camera body is equipped with a third data terminal that outputs a third data signal from the communication unit to the camera body in synchronization with the aforementioned clock signal, The ready terminal, the first data terminal, the second data terminal, the first clock terminal, and the third data terminal are arranged in order in this accessory.

Images