JP7255399B2 - camera system - Google Patents

Description

The present invention relates to camera systems .

Camera accessories include a master lens capable of forming a subject image and an intermediate accessory mountable between the master lens and the camera body (see Patent Document 1). In the prior art, in order to distinguish between the master lens and the intermediate accessory when viewed from the camera body, it was necessary to change the number of terminals between the master lens and the intermediate accessory.

JP-A-63-38926

According to a first aspect, a camera system has at least one accessory and a camera body communicable with the accessory, the camera body comprising a body-side mount and detachable from the body-side mount. and a receiver for receiving an instruction signal transmitted from the camera body, wherein the instruction signal includes identification information and an instruction from the camera body. The identification information is information for identifying an accessory attached to the body-side mount and capable of communicating with the camera body.
According to a second aspect, a camera system has at least one accessory and a camera body communicable with the accessory, the camera body comprising a body-side mount and detachable from the body-side mount. and a receiver for receiving an instruction signal transmitted from the camera body, wherein the instruction signal includes identification information and an instruction from the camera body. The identification information is information for specifying one communication partner among the accessories attached to the body-side mount.
According to a third aspect, a camera system has at least one accessory and a camera body communicable with the accessory, the camera body comprising a body-side mount and detachable from the body-side mount. and a receiver for receiving an instruction signal transmitted from the camera body, wherein the instruction signal includes identification information and an instruction from the camera body. The identification information is information indicating the order of attachment from the body-side mount.

1 is a perspective view illustrating a camera system; FIG. 1 is a block diagram for explaining the main configuration of a camera system including a teleconverter; FIG. 4 is a circuit diagram schematically showing electrical connections between the camera body, teleconverter and interchangeable lens; FIG. 4 is a diagram illustrating timings of command data communication performed between a body side communication section and a lens side communication section; FIG. FIG. 5 is a diagram illustrating the timing of hotline communication performed between the body-side communication unit and the lens-side communication unit; FIG. 6(a) is a diagram illustrating the structure of a command packet, and FIG. 6(b) is a diagram illustrating the structure of a data packet. FIG. 10 is a diagram illustrating the flow of processing in device ID allocation command data communication and normal command data communication; 4 is a flowchart for explaining the flow of processing executed by the body-side control unit, the control/communication unit, and the lens-side control unit during device ID allocation command data communication; 4 is a flowchart for explaining the flow of normal command data communication executed during normal command data communication in a body side control section, a control/communication section, and a lens side control section;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a camera system 1 before camera accessories are attached to a camera body 2 according to one embodiment of the invention. FIG. 2 is a block diagram for explaining the main configuration of the camera system 1. As shown in FIG.
The camera accessory of this embodiment includes an interchangeable lens 3 as a master lens and a teleconverter 4 as an intermediate accessory. The master lens of this embodiment refers to a device that is attached to the camera body 2 and capable of forming a subject image. Further, the master lens of the present embodiment refers to a device that is not attached to the subject side in a communicable state with other camera accessories. Further, the intermediate accessory in this embodiment is a device that can be attached to the subject side in a state in which other devices can communicate with each other, and is also called a non-master lens. A non-master lens is used in combination with a master lens.
The coupling between the camera body 2 and the camera accessory and the coupling between the camera accessories are performed by a bayonet structure of the body-side mount and the lens-side mount. Therefore, the body-side mount 210 of the camera body 2 and the front-side mount 413 arranged on the lens side of the teleconverter 4 have substantially the same shape, and the lens-side mount 310 of the interchangeable lens 3 and the body side of the teleconverter 4 have substantially the same shape. The shape of the rear mount 412 arranged in the rear mount 412 is substantially the same. Therefore, the interchangeable lens 3 can be used directly attached to the camera body 2 without the teleconverter 4, or can be used indirectly attached to the camera body 2 via the teleconverter 4. When the camera body 2 and the camera accessory, or the camera accessories are coupled to each other, the terminals provided on the respective mounts come into physical contact with each other and are electrically connected.

<Interchangeable lens>
The interchangeable lens 3 includes a lens side mount 310 , a lens side control section 330 , a lens side communication section 340 , a lens side storage section 350 , a lens side power supply circuit 352 , an imaging optical system 360 , a lens drive section 370 and an aperture drive section 380 . have.

A lens-side terminal holding portion 320 is provided on the annular lens-side mount 310 . The lens-side terminal holding portion 320 arranges a plurality of lens-side terminals in an arc around the optical axis. The plurality of lens-side terminals include, for example, an attachment detection terminal for transmitting a signal indicating that the interchangeable lens 3 is attached to the camera body 2 to the camera body 2, and an attachment detection terminal used for communication between the interchangeable lens 3 and the camera body 2. It includes a communication terminal, a power supply terminal for supplying power from the camera body 2 to the interchangeable lens 3, and a grounding terminal.

Signals and power transmitted by each terminal are transmitted from the interchangeable lens 3 to the camera body 2 via the teleconverter 4 when the interchangeable lens 3 is attached to the camera body 2 via the teleconverter 4 . Further, when the interchangeable lens 3 is directly attached to the camera body 2 , the signal is directly transmitted from the interchangeable lens 3 to the camera body 2 .

The lens-side control section 330 is composed of a microcomputer, its peripheral circuits, and the like. The lens side control section 330 executes control programs stored in the lens side storage section 350 to control each section of the interchangeable lens 3 . In response to a request from the camera body 2 , the lens-side control section 330 reads data stored in the lens-side storage section 350 and transmits the data from the lens-side communication section 340 via the teleconverter 4 or directly to the camera body 2 . Send to The lens side control section 330 is connected to the lens side communication section 340 , the lens side storage section 350 , the lens driving section 370 and the diaphragm driving section 380 .

Based on instructions from the body side communication section 240 , the lens side communication section 340 performs predetermined communication with the body side communication section 240 via the teleconverter 4 or directly. The lens-side communication section 340 is connected to the lens-side control section 330 and the communication terminal described above. Through communication between the body-side communication unit 240 and the lens-side communication unit 340, an instruction to move the lens 361, which will be described later, and a request to transmit information such as data stored in the lens-side storage unit 350 are transmitted. The image is transmitted from the camera body 2 to the interchangeable lens 3 via the teleconverter 4 or directly. On the other hand, based on instructions from the body-side communication unit 240, information indicating the state inside the interchangeable lens 3, such as the position of the lens 361 after movement, and data read from the lens-side storage unit 350 are transferred from the interchangeable lens 3 to the telescope. It is transmitted to the camera body 2 via the converter 4 or directly.

The lens side storage unit 350 is configured by a nonvolatile storage medium. The lens-side storage unit 350 is controlled by the lens-side control unit 330 to record and read data. The lens-side storage unit 350 stores data indicating the model name of the interchangeable lens 3 (also referred to as model name information) and the optical characteristics of the imaging optical system 360, in addition to storing control programs and the like executed by the lens-side control unit 330. Data indicating the device ID, data indicating the device ID, and the like can be stored. The device ID is an identifier used to identify a camera accessory to which the camera body 2 is attached, and is data composed of a code or the like used to specify a communication partner from among the attached camera accessories. The device ID is transmitted from the camera body 2 each time the interchangeable lens 3 is attached to the camera body 2 (or attachment is detected). The lens side storage section 350 is connected to the lens side control section 330 .

The power supply circuit 352 distributes electric power supplied from the camera body 2 to the interchangeable lens 3 via the power supply terminal to each part in the interchangeable lens 3 . The power supply circuit 352 is connected to the power supply terminals described above.

The imaging optical system 360 forms a subject image on the imaging plane via the teleconverter 4 or directly. The optical axis O of the imaging optical system 360 substantially coincides with the center positions of the lens side mount 310, the front side mount 413 of the teleconverter 4, the rear side mount 412 of the teleconverter 4, the body side mount 210, and the imaging plane. The imaging optical system 360 is composed of, for example, a plurality of lenses 361 including a focusing lens, a zoom lens, etc., and an aperture 362 . At least part of the plurality of lenses 361 is configured to be movable in the direction of the optical axis O by the lens drive unit 370 or manual operation. The position of each lens in the direction of the optical axis O is configured to be detectable by an encoder or the like of the lens drive section 370 .

A diaphragm 362 adjusts the amount of light incident on the imaging device 260 . The diaphragm 362 is configured such that the aperture diameter (aperture value) can be changed by the diaphragm driver 380 or manual operation. The aperture diameter of the diaphragm 362 is configured to be detectable by an encoder or the like of the diaphragm driver 380 .

The lens driving section 370 is composed of, for example, a motor and a lens driving mechanism. The lens driving section 370 moves the focusing lens included in the lens 361 along the direction of the optical axis O based on the instruction from the lens side control section 330 . Lens driver 370 is connected to lens-side controller 330 .
Aperture driving section 380 is composed of a motor and a diaphragm driving mechanism. The aperture driving section 380 changes the aperture diameter of the aperture 362 based on the instruction from the lens side control section 330 . Aperture driver 380 is connected to lens-side controller 330 .

<Teleconverter 4>
The teleconverter 4 has a rear mount 412 facing the body side mount 210 when attached to the camera body 2, a front side mount 413 facing the lens side mount 310 when the interchangeable lens 3 is attached, and an accessory side mount. It has a control/communication section 435 , an accessory side storage section 437 , a switch 450 , an accessory side power supply circuit 452 and a lens 460 .

The rear mount 412 is provided with a rear terminal holding portion 422 in which a plurality of terminals are arranged in an arc around the optical axis. The front mount 413 is provided with a front terminal holding portion 423 in which a plurality of terminals are arranged in an arc around the optical axis. A plurality of terminals arranged in the rear terminal holding portion 422 and the front terminal holding portion 423 include attachment detection terminals that transmit a signal indicating that a camera accessory is attached. It includes a communication terminal to be used, a power supply terminal for supplying power from the camera body 2 to the camera accessory, and a grounding terminal. Here, the terminals included in the rear terminal holding portion 422 arranged on the rear side (camera body 2 side) of the intermediate accessory are the same as the terminals included in the lens side terminal holding portion 320 of the lens side mount 310 . The terminals included in the front terminal holding portion 423 arranged on the front side (object side) of the intermediate accessory are the same as the terminals included in the body side terminal holding portion 220 arranged on the body side mount 210 .

The accessory-side control/communication section 435 is composed of a microcomputer, a storage section, peripheral circuits thereof, and the like. The accessory-side control/communication unit 435 executes control programs stored in the accessory-side storage unit 437 to control the opening and closing of the switch 450 . When the switch 450 is closed, power supplied from the camera body 2 to the power supply circuit 452 is supplied to the interchangeable lens 3, and when the switch 450 is opened, power supply to the interchangeable lens 3 is cut off. Also, the accessory-side control/communication section 435 performs predetermined communication with the body-side communication section 240 . Furthermore, the accessory-side control/communication section 435 reads data stored in the accessory-side storage section 437 and transmits the data to the camera body 2 upon request from the camera body 2 . Also, the accessory-side control/communication unit 435 controls operations, detection, and the like within the teleconverter 4 according to instructions from the camera body 2 . The accessory-side control/communication unit 435 is connected to the communication terminal and switch 450 described above.

The accessory-side storage unit 437 is controlled to record and read data by the accessory-side control/communication unit 435 . The accessory-side storage unit 437 stores control programs and the like executed by the accessory-side control/communication unit 435, as well as data indicating the model name of the teleconverter 4 (also referred to as model name information), data indicating the device ID, and the like. can be stored. The accessory-side storage unit 437 is connected to the accessory-side control/communication unit 435 .

The switch 450 is composed of a semiconductor switch element using, for example, an FET (field effect transistor). The on/off of the switch 450 is controlled by the control signal input from the accessory-side control/communication section 435 to the switch 450 . Switch-off means contact opening, and switch-on means contact closing. For example, the switch 450 is in a state in which a high level (hereinafter, “H level”) control signal is not input from the accessory-side control/communication unit 435 (that is, a low level (hereinafter, “L level”) control signal is input. state), and turned on when an H-level control signal is input from the control/communication unit 435 on the accessory side. The switch 450 is connected to the power supply circuit 452 , the power supply terminal of the second lens-side terminal, and the accessory-side control/communication section 435 .

The power supply circuit 452 distributes the power supplied to the teleconverter 4 via the power supply terminal and the grounding terminal on the body side to each part in the teleconverter 4 or the interchangeable lens 3 . A power supply circuit 452 is connected to the power supply terminal and the switch 450 .

A lens 460 is a teleconverter lens that converts the focal length of the lens 361 by, for example, 1.4 times. When the teleconverter 4 is attached to the interchangeable lens 3, the focal length of the interchangeable lens 3 is 1.4 times longer than when the teleconverter 4 is not attached.

<Camera body>
The camera body 2 has a body side mount 210 , a body side control section 230 , a body side communication section 240 , a power supply section 250 , an imaging element 260 , a signal processing section 270 , an operation member 280 and a display section 290 .

A body-side terminal holding portion 220 is provided on the ring-shaped body-side mount 210 . The body-side terminal holding portion 220 has a plurality of body-side terminals. The plurality of body-side terminals include, for example, an attachment detection terminal that transmits a signal indicating that the interchangeable lens 3 is attached to the camera body 2 to the camera body 2 via the teleconverter 4 or directly. It includes a communication terminal used for communication with the teleconverter 4 and the interchangeable lens 3, a power supply terminal for supplying power from the camera body 2 to the teleconverter 4 and the interchangeable lens 3, and a grounding terminal.

The body-side control section 230 is composed of a microcomputer, its peripheral circuits, and the like. The body-side control section 230 executes control programs stored in the storage section 235 to control each section within the camera body 2 . The body-side control section 230 is connected to the body-side communication section 240, the power supply section 250, the imaging device 260, the signal processing section 270, the operation member 280, the display section 290, and the attachment detection terminal described above.

Body-side control unit 230 includes storage unit 235 . The storage unit 235 is controlled to record and read data by the body-side control unit 230 . The storage unit 235 can store, for example, a control program executed by the body-side control unit 230, model name information of the camera accessory, data indicating optical characteristics of the camera accessory, and the like. Further, when the camera accessory is attached, the body-side control unit 230 performs device ID allocation, which will be described later, and holds and temporarily stores the device ID transmitted to the camera accessory. The body-side control unit 230 erases the held device ID information when the power is turned off or when the camera accessory is removed.

The body side communication section 240 performs the communication described above with the lens side communication section 340 or the accessory side control/communication section 435 . Body-side communication section 240 is connected to body-side control section 230 and the communication terminals described above.
The power supply unit 250 converts the voltage of a battery (not shown) into voltage used in each part of the camera system 1 and supplies the voltage to each part of the camera body 2 , the interchangeable lens 3 and the teleconverter 4 . Power supply unit 250 can switch on and off power supply for each power supply destination according to instructions from body-side control unit 230 . Power supply unit 250 is connected to body-side control unit 230 and the power supply terminal described above.

The imaging device 260 is a solid-state imaging device such as a CMOS image sensor or a CCD image sensor. The image pickup device 260 picks up a subject image on the image pickup plane and outputs an image pickup signal according to a control signal from the body side control section 230 . The imaging device 260 is connected to the body side control section 230 and the signal processing section 270 .

The imaging element 260 has pixels for image generation (referred to as imaging pixels) and pixels for focus detection (referred to as focus detection pixels). Signals generated by the imaging pixels (hereinafter referred to as imaging pixel signals) are used for generating image data by the signal processing unit 270, which will be described later. A signal generated by a focus detection pixel (hereinafter referred to as a focus detection pixel signal) is used by a signal processing unit 270, which will be described later, to detect the imaging state of an image formed by the interchangeable lens 3, in other words, a focus detection signal for detecting the focus position. Used for processing.

The signal processing unit 270 performs predetermined image processing on the imaging pixel signals output from the imaging device 260 to generate image data. The generated image data is recorded in a predetermined file format in a storage medium (not shown), or used for image display by the display unit 290 . The signal processing section 270 is connected to the body side control section 230 , the imaging element 260 and the display section 290 .

In addition, the signal processing unit 270 detects the focal position of the interchangeable lens 3 using the focus detection pixel signal output from the imaging device 260, and calculates the defocus amount. The signal processing unit 270 calculates the movement amount of the focusing lens to the in-focus position based on the calculated defocus amount.

An operation member 280 including a release button, operation switches, etc. is provided on the exterior surface of the camera body 2 . By operating the operation member 280, the user issues a photographing instruction, a photographing condition setting instruction, and the like. Operation member 280 sends an operation signal according to the user's operation to body-side control section 230 .
The display unit 290 is configured by, for example, a liquid crystal display panel. The display unit 290 displays an image based on the image data processed by the signal processing unit 270, an operation menu screen, etc., according to an instruction from the body-side control unit 230. FIG. Display unit 290 is connected to body-side control unit 230 and signal processing unit 270 .

<Terminal details>
FIG. 3 is a circuit diagram schematically showing electrical connections among the camera body 2, teleconverter 4, and interchangeable lens 3. As shown in FIG. In FIG. 3, arrows indicate the flow of signals.
The body-side terminal holding portion 220 of the body-side mount 210 holds the LDET (B) terminal, the VBAT (B) terminal, the PGND (B) terminal, the V33 (B) terminal, the GND (B) terminal, and the RDY terminal as the body-side terminals. (B) terminal, DATAB (B) terminal, CLK (B) terminal, DATAL (B) terminal, HCLK (B) terminal, and HDATA (B) terminal. These eleven body-side terminals are collectively referred to as a body-side terminal group. Each terminal of the body-side terminal group is arranged in the order shown in FIG.

A lens-side terminal holding portion 320 of the lens-side mount 310 includes an LDET (L) terminal, a VBAT (L) terminal, a PGND (L) terminal, a V33 (L) terminal, a GND (L) terminal, an RDY (L) terminal, and a DATAB terminal. (L) terminal, CLK (L) terminal, DATAL (L) terminal, HCLK (L) terminal, and HDATA (L) terminal. These eleven lens-side terminals are collectively referred to as a lens-side terminal group. Each terminal of the lens side terminal group is arranged in the order shown in FIG.

In the teleconverter 4, the second terminal group included in the front terminal holding portion 423 is the same as the body side terminal group, and the first terminal group included in the rear terminal holding portion 422 is the same as the lens side terminal group. In FIG. 3 , notation of each terminal of the rear terminal holding portion 422 and the front terminal holding portion 423 is omitted.

Furthermore, the accessory-side control/communication unit 435 is configured to connect between the RDY (B) terminal of the camera body 2 and the RDY (L) terminal of the interchangeable lens 3, the DATAB (B) terminal of the camera body 2 and the DATAB ( L) terminal, between the CLK(B) terminal of the camera body 2 and the CLK(L) terminal of the interchangeable lens 3, and between the DATAL(B) terminal of the camera body 2 and the DATA(L) terminal of the interchangeable lens 3. are connected in parallel between the

RDY (B) terminal, DATAB (B) terminal, CLK (B) terminal, DATAL (B) terminal, HCLK (B) terminal, HDATA (B) terminal, RDY (L) terminal, DATAB (L) terminal, CLK ( The L) terminal, the DATAL (L) terminal, the HCLK (L) terminal, and the HDATA (L) terminal are communication terminals described above. Among the communication terminals, 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 the HDATA (B) terminal of the communication terminals are used for hotline communication, which will be described later. This embodiment has two communication systems, command data communication and hotline communication. Command data communication and hotline communication are separate and independent communication systems.
The RDY (B) terminal, DATAB (B) terminal, CLK (B) terminal, DATAL (B) terminal, HCLK (B) terminal, and HDATA (B) terminal are connected to the body side control section via the body side communication section 240, respectively. 230. The RDY (L) terminal, DATAB (L) terminal, CLK (L) terminal, DATAL (L) terminal, HCLK (L) terminal, and HDATA (L) terminal are connected to the lens side control section via the lens side communication section 340. 220.

The RDY(B) terminal is an input terminal to which a signal from the RDY(L) terminal is input. A signal indicating whether command data communication is possible with the interchangeable lens 3 (hereinafter referred to as an RDYL signal) is input to the RDY(B) terminal from the RDY(L) terminal of the interchangeable lens 3 via the teleconverter 4. be done. A signal indicating whether or not the teleconverter 4 is capable of command data communication (hereinafter referred to as an RDYA signal) is input from the teleconverter 4 to the RDY(B) terminal. When the command data communication is possible, the lens-side control section 330 changes the potential of the RDYL signal from the L level to the L level via the H level once. The accessory-side control/communication unit 435 changes the potential of the RDYA signal from the L level to the L level via the H level once when the command data communication is possible. The RDY(B) terminal transmits the RDYB signal to the body side control section 230 via the body side communication section 240 by receiving the RDYL signal or the RDYA signal. When the body-side control unit 230 detects that the potential of the RDYB signal has changed from L level→H level→L level, it determines whether or not the camera accessory specified by the device ID is capable of command data communication. .
The lens-side control section 330 can switch the output of the RDY(L) terminal of the interchangeable lens 3 to a high impedance state. Also, the accessory-side control/communication section 435 can switch the output of the RDY(L) terminal of the teleconverter 4 to a high impedance state. The high impedance state refers to a state in which the connection with body side communication section 240 is substantially cut off. When the accessory-side control/communication unit 435 cuts off the connection with the body-side communication unit 240 , the lens-side communication unit 340 becomes connected with the body-side communication unit 240 . Also, when the lens side communication section 340 cuts off the connection with the body side communication section 240 , the accessory side control/communication section 435 becomes connected with the body side communication section 240 . When the accessory-side control/communication section 435 is connected to the body-side communication section 240 , the RDYA signal from the teleconverter 4 is transmitted to the RDY (B) terminal of the camera body 2 . When the lens side communication section 340 is connected to the body side communication section 240 , the RDYL signal from the interchangeable lens 3 is transmitted to the RDY (B) terminal of the camera body 2 . The RDYA signal output by the accessory-side control/communication unit 435 is a signal determined and generated by the accessory-side control/communication unit 435 . The RDYL signal output by the lens side communication section 340 is a signal determined and generated by the lens side control section 330 .

The DATAB (B) terminal outputs a data signal (hereinafter referred to as DATAB signal) toward the DATAB (L) terminal of the interchangeable lens 3 or teleconverter 4 . The DATAB (L) terminal is an input terminal for inputting the DATAB signal from the DATAB (B) terminal. Therefore, the DATAB signal from the body side communication section 240 is input to the lens side communication section 340 or the accessory side control/communication section 435 .

The DATAL (B) terminal is an input terminal to which a signal from the DATAL (L) terminal is input. A data signal (hereafter, DATAA signal) from the DATAL (L) terminal of the teleconverter 4 is input to the DATAL (B) terminal, or a data signal (hereafter, DATA signal) from the DATAL (L) terminal of the interchangeable lens 3 is input to the DATAL (B) terminal. ) is input through the teleconverter 4 .
The lens side communication section 340 can switch the output of the DATAL (L) terminal of the interchangeable lens 3 to a high impedance state. Also, the accessory-side control/communication unit 435 can switch the output of the DATAL (L) terminal of the teleconverter 4 to a high impedance state. When the accessory-side control/communication section 435 is connected to the body-side communication section 240 , the DATAA signal from the teleconverter 4 is transmitted to the DATAL (B) terminal of the camera body 2 . When the lens side communication section 340 is connected to the body side communication section 240 , the DATAL signal from the interchangeable lens 3 is transmitted to the DATAL (B) terminal of the camera body 2 . The DATAA signal output by the accessory-side control/communication unit 435 is a signal determined and generated by the accessory-side control/communication unit 435 . The DATAL signal output by the lens-side communication section 340 is a signal determined and generated by the lens-side control section 330 .

The CLK(B) terminal is an output terminal from which a clock signal (hereinafter, CLK signal) is output toward the CLK(L) terminal. The CLK(L) terminal is an input terminal to which the CLK signal from the CLK(B) terminal is input. The CLK signal from the body side communication section 240 is input to the lens side communication section 340 via the teleconverter 4 . The CLK signal from the body side communication section 240 is input to the accessory side control/communication section 435 .

The HCLK (B) terminal is an input terminal for inputting a clock signal (hereinafter referred to as HCLK signal) from the HCLK (L) terminal of the interchangeable lens 3 to the body side communication section 240 . The HCLK (L) terminal is an output terminal that outputs the HCLK signal toward the HCLK (B) terminal.
The HDATA (B) terminal is an input terminal through which a data signal (hereinafter referred to as HDATA signal) from the HDATA (L) terminal of the interchangeable lens 3 is input to the body side communication section 240 . The HDATA (L) terminal is an output terminal that outputs an HDATA signal toward the HDATA (B) terminal.

The LDET (B) terminal is the attachment detection terminal described above. In the camera body 2, the LDET (B) terminal is connected to the body side control section 230 via the resistor R2. The resistor R2 and the body-side control section 230 are connected via the power supply V33 supplied from the power supply section 250 and the resistor R1.
On the other hand, in the interchangeable lens 3, the LDET (L) terminal is connected (grounded) to the GND potential via the resistor R3. In the teleconverter 4, the LDET (B) terminal and the LDET (L) terminal are not grounded. In this embodiment, the LDET (L) terminal is installed in the master lens, and the LDET (B) terminal and the LDET (L) terminal are not grounded in the non-master lens.
With such a configuration, the LDET (B) terminal is pulled up inside the camera body 2 and becomes the potential of the power supply V33 when the interchangeable lens 3 is not attached. When the interchangeable lens 3 is attached, the ground potential LDET (L) terminal is connected to the pulled-up LDET (B) terminal, and the potential of the LDET (B) terminal is lowered. From this, the camera body 2 can detect that the interchangeable lens 3 is attached. When only the teleconverter 4 is attached to the camera body 2 and the interchangeable lens 3 is not attached, the LDET (B) terminal remains at the potential of the power supply V33.

The VBAT (B) terminal is a power supply terminal that supplies power to the camera accessory. The power supplied from the VBAT(B) terminal to the VBAT(L) terminal drives the lens driving section 370 and the diaphragm driving section 380 . Since the lens driving section 370 and the aperture driving section 380 include actuators such as motors, they require higher voltage and larger current than the power supplied to the lens side control section 330 . In the following description, the voltage applied to the VBAT (B) terminal by the power supply section 250 is referred to as drive system voltage. The PGND (B) terminal is a ground terminal corresponding to the VBAT (B) terminal. The PGND (B) terminal is connected to the PGND (L) terminal.

The V33(B) terminal is also a power supply terminal for supplying power to the camera accessory. The power supplied from the V33(B) terminal to the teleconverter 4 is distributed by the power supply circuit 452 to each section of the teleconverter 4 such as the accessory-side control/communication section 435 . Also, the power output from the power supply circuit 452 is supplied to the V33 (L) terminal of the interchangeable lens 3 via the switch 450 . The power supplied from the V33(L) terminal to the interchangeable lens 3 is distributed by the power supply circuit 352 to each section of the interchangeable lens 3 such as the lens-side control section 330 .

The lens-side control section 330 is connected to the V33(B) terminal and operates at a voltage lower than the drive system voltage and with a small current. In the following description, the voltage applied by the power supply unit 250 to the V33(B) terminal is referred to as circuit system voltage. The GND (B) terminal is a ground terminal corresponding to the V33 (B) terminal. The GND (B) terminal is connected to the GND (L) terminal of the interchangeable lens 3 via the signal line inside the teleconverter 4 as described above.
In FIG. 3, arrows indicate directions in which electric power is supplied. Power from the circuit system voltage (hereinafter referred to as circuit system power) is also distributed by the power supply section 250 to each section of the camera body 2 such as the body side control section 230 .

In this embodiment, the power supply circuit 452 and the switch 450 of the teleconverter 4 are inserted and connected in series between the V33(B) terminal of the camera body 2 and the V33(L) terminal of the interchangeable lens 3 . When the switch 450 is turned on, the circuit system power is supplied to the V33 (L) terminal through the power supply circuit 452, and when the switch 450 is turned off, the supply of the circuit system power to the V33 (L) terminal is interrupted. . Since the circuit system power is supplied to the accessory-side control/communication unit 435 on the upstream side of the switch 450, the circuit system power is supplied regardless of whether the switch 450 is opened or closed.

The switch 450 is controlled to be open until the device ID allocation command data communication (described later) between the accessory-side control/communication unit 435 and the body-side communication unit 240 is completed after the accessory-side control/communication unit 435 is activated. be done. The switch 450 is closed after the device ID assignment command data communication between the accessory-side control/communication unit 435 and the body-side communication unit 240 is completed. By closing the switch 450, the camera body 2 and the next camera accessory (the interchangeable lens 3 in this embodiment) are connected, and circuit system power is supplied.

In the interchangeable lens 3 , the VBAT(L) terminal is connected to the power supply circuit 351 . The output of the power supply circuit 351 and the PGND (L) terminal are connected to the lens driving section 370 and the diaphragm driving section 380 . Also, the V33(L) terminal is connected to the power supply circuit 352 as described above. The output of the power supply circuit 352 and the GND (L) terminal are connected to each unit such as the lens side control unit 330 and the like.

<Description of command data communication>
Next, command data communication will be described with reference to FIG. In command data communication, bidirectional transmission and reception of data signals are possible between the lens side control section 330 and the body side control section 230 .
Here, a first example of use is a mode of use in which the interchangeable lens 3 is indirectly attached to the camera body 2 via the teleconverter 4, and a use in which the interchangeable lens 3 is directly attached to the camera body 2 without the teleconverter 4. Let the form be a second example of use. FIG. 4 is a diagram illustrating timings of various signals in the second usage example.

In this embodiment, two types of command data communication are performed as command data communication: device ID assignment command data communication and normal command data communication. Device ID assignment command data communication is command data communication performed by the camera body 2 to assign device IDs to camera accessories such as the interchangeable lens 3 and the teleconverter 4 attached to the camera body 2 . Normal command data communication is command data communication performed after a device ID is assigned by device ID assignment command data communication (see FIG. 7).
In one command data communication, after transmitting one command packet 402 from the camera body 2 to the camera accessory, one data packet 406, 407 is transmitted and received between the camera body 2 and the camera accessory. .
The command packet 402 includes data indicating a request for model name information, data indicating a request for a discrimination signal for discriminating whether the lens is a master lens or a non-master lens, data indicating a device ID indicating the destination of the command data communication, camera It contains data indicating a request for information about the optical properties of the accessory, data indicating what data will be sent in the next data packet, data indicating the data length of the next data packet, and so on.
The data packet 406 transmitted from the camera body 2 to the camera accessory includes data indicating the driving amount of the movable part in the camera accessory, data for communicating the operating state within the camera body 2, and data for communicating the device ID. , etc.
The data packet 407 transmitted from the camera accessory to the camera body 2 includes data indicating model name information of the camera accessory, data indicating a discrimination signal for discriminating whether the lens is a master lens or a non-master lens, and data representing a moving part in the camera accessory. data to convey the operating state of the camera, data indicating information on the optical characteristics of the camera accessory, data indicating the magnification of the teleconverter 4, and the optics of the interchangeable lens after the predetermined interchangeable lens is attached to the teleconverter 4 data indicating characteristics, etc.

Although FIG. 4 and the following description show command data communication between the body side communication section 240 and the lens side communication section 340, command data communication between the body side communication section 240 and the accessory side control/communication section 435 are shown. In this case, the RDYL signal becomes the RDYA signal, the DATAA signal becomes the DATAA signal, and the lens side communication section 340 becomes the accessory side control/communication section 435 in FIG. 4 and the following description.

The lens-side communication unit 340 sets the potential of the RDYL signal to L level at the start of command data communication. Further, when the lens-side communication unit 340 determines that command data communication is possible, it keeps the potential of the RDYL signal at the L level. Further, the lens-side communication unit 340 sets the level of the RDYL signal to H level when command data communication cannot be performed.

When the RDYL signal is at the L level at the start of command data communication (T1), body side communication section 240 starts outputting clock signal 401 as the CLK signal. Thereby, the clock signal 401 is transmitted from the camera body 2 to the interchangeable lens 3 . The frequency of clock signal 401 is, for example, 8 MHz.

The body side communication section 240 outputs a command packet 402 as a DATAB signal in synchronization with the clock signal 401 . In FIG. 4, the command packet 402 is shown by switching between H level and L level. When the transmission of the command packet 402 is completed, the body side communication section 240 ends the output of the clock signal 401 .

The lens-side control unit 330 uses an error detection code (for example, checksum data) included in the command packet 402 received by the lens-side communication unit 340 to determine whether there is a communication error in the command packet 402 . When determining that there is no communication error, the lens side communication section 340 sets the level of the RDYL signal to H level (T2). Then, the lens side control section 330 starts the first control processing 404 based on the command packet 402 .

When the first control processing 404 by the lens-side control unit 330 is completed, the lens-side communication unit 340 can set the level of the RDYL signal to L level (T3). Body side communication section 240 outputs clock signal 405 as a CLK signal when the level of the input RDYL signal becomes L level.

The body side communication section 240 outputs a data packet 406 as a DATAB signal in synchronization with the clock signal 405 . In FIG. 4, the data packet 406 is indicated by switching between H level and L level. When the transmission of the data packet 406 of the predetermined length is completed, the body side communication section 240 ends the output of the clock signal 405 (T4).

On the other hand, when the clock signal 405 is input, the lens side communication section 340 outputs a data packet 407 as a DATAL signal in synchronization with the clock signal 405 . In FIG. 4, the data packet 407 is indicated by switching between H level and L level.

The lens-side control unit 330 uses an error detection code (for example, checksum data) included in the data packet 406 received by the lens-side communication unit 340 to determine whether there is a communication error in the data packet 406 . When it is determined that there is no communication error, the lens side communication section 340 sets the level of the RDYL signal to H level again (T4). Then, the lens-side control section 330 starts the second control processing 408 based on the data packet 406. FIG.

<Packet structure>
FIG. 6A is a diagram illustrating the structure of a command packet 402, and FIG. 6B is a diagram illustrating the structures of data packets 406 and 407. FIG. Command packet 402 and data packets 406 and 407 each include data for synchronization at the beginning.
The command packet 402 is, for example, 8-byte fixed-length data. "Dev ID" 63 is fixed-length data including the device ID of the communication partner. Since normal command data communication is performed after device ID allocation command data, the command packet 402 is transmitted including the device ID of the communication partner. Therefore, data indicating the device ID of the communication partner is set in "Dev ID" 63 . On the other hand, in the case of device ID allocation command data communication, the command packet 402 is transmitted without designating the device ID of the communication partner because it is performed before allocating the device ID. In that case, in the device ID allocation command data communication, a predetermined initial value is set to the "Dev ID" 63, and the command packet 402 remains fixed length.

"CMD" 64 is fixed-length data indicating an instruction, request, or the like. “CMD” 64 contains data representing instructions and requests from the camera body 2 . “Length” 66 is fixed-length data indicating the data length (that is, the amount of information) of the data packet 406 to be transmitted next. Since the command packet 402 indicates the data length of the subsequent data packet 406, the device on the receiving side (interchangeable lens 3 or teleconverter 4) detects the data for synchronization when receiving the data packet 406, and then The data length indicated by “Length” 66 can be measured to terminate reception of data packet 406 .

Data packets 406 and 407 are m-byte variable-length data having the number of data indicated by “Length” 66 . "DATA1" 72, "DATA2" 73, . . . "DATAn"m-1 are data divided into 1-byte lengths. Information to be transmitted is set in units of one byte such as "DATA1" 72, "DATA2" 73, and so on. In the case of the data packet 406 of the device ID allocation command data communication, data indicating the device ID is set in "DATA1" 72, for example. In the case of the data packet 407 of normal command data communication, data indicating information from the camera accessory is set in "DATA1" 72, "DATA2" 73, ... "DATAn"m-1.

<Description of first and second control processing>
Next, an example of the first control processing 404 and the second control processing 408 of command data communication shown in FIG. 4 will be described.
For example, assume that the command packet 402 includes an instruction to drive the lens 361 . As the first control process 404 , the lens-side control unit 330 generates a data packet 407 indicating that an instruction to drive the lens 361 has been received. Next, as second control processing 408 , lens-side control section 330 instructs lens driving section 370 to move lens 361 by the movement amount indicated by data packet 406 . As a result, the lens 361 moves in the optical axis O direction. When the lens-side control unit 330 issues an instruction to move the lens 361 to the lens driving unit 370, the lens-side communication unit 340 determines that the second control process 408 is completed and sets the level of the RDYL signal to L level (T5).
Also, for example, it is assumed that the command packet 402 includes an instruction to start hotline communication. As the first control process 404, the lens-side control unit 330 generates a data packet 407 indicating that an instruction to start hotline communication has been received. Next, the lens-side control unit 330 outputs an instruction to start hotline communication to the lens-side communication unit 340 as the second control process 408, and changes the level of the RDYL signal to L level as the second control process 408 is completed. (T5).

<Process flow of command data communication>
Next, the flow of command data communication processing when the teleconverter 4 is attached as an accessory will be described. FIG. 7 is a time chart for explaining the flow of processing in device ID assignment command data communication and normal command data communication performed after the device ID is assigned. 7, RDYB signal input to camera body 2, DATAB signal output from camera body 2, RDYA signal output from accessory-side control/communication section 435, and output from accessory-side control/communication section 435. RDYL signal output from the lens-side controller 330 and DATAL signal output from the lens-side controller 330 are shown. Also, in FIG. 7, the horizontal axis represents time. Reference numerals beginning with S in FIG. 7 are step numbers indicating corresponding processes in the flow charts of FIGS. FIG. 8 is a flow chart showing the flow of processing executed during device ID allocation command data communication. FIG. 9 is a flow chart showing the flow of processing executed during normal command data communication.

To explain the rough flow of FIG. 7, the period from time t10 to time t20 is a period during which the camera body 2 performs device ID assignment command data communication with the teleconverter 4 and the interchangeable lens 3 in order. Then, after time t20, the camera body 2 performs normal command data communication with the interchangeable lens 3 or the teleconverter 4 individually.
The body side communication section 240 performs device ID allocation command data communication with the accessory side control/communication section 435 from time t10 to time t12, and performs device ID allocation command data communication with the lens side communication section 340 from time t13 to time t20. .

When detecting that a camera accessory is attached, the body-side control unit 230 assigns a device ID to each camera accessory by performing device ID assignment command data communication for each attached camera accessory. Thereafter, in normal command data communication, body-side control section 230 designates the device ID of the communication partner in each command data communication. In the present embodiment, the body-side control unit 230 allocates a device ID each time the attachment of a camera accessory is detected by the attachment detection terminal or the power is turned on. Therefore, even if the past device ID is held in the storage unit in the body side control unit 230 before the device ID allocation command data communication is performed, the device ID is reallocated before communication is performed.

(Equipment ID allocation command data communication)
When the interchangeable lens 3 is indirectly attached to the camera body 2 via the teleconverter 4, the potential of the LDET (B) terminal drops. The body-side control section 230 supplies circuit system power to the V33 (B) terminal of the teleconverter 4 when detecting a drop in the potential of the LDET (B) terminal. As a result, power is supplied to the accessory-side control/communication unit 435, and the accessory-side control/communication unit 435 is activated at time t10. The activated accessory-side control/communication unit 435 changes the RDYA signal from L level→H level→L level (S410), and notifies the camera body 2 that it is ready to receive device ID allocation command data communication. .

The body-side control section 230 notified by the RDYB signal that the teleconverter 4 is ready for reception outputs the DATAB signal in synchronization with the clock signal 401 (S230). The DATAB signal at this time includes a command packet 402, which includes an instruction to assign a device ID to the teleconverter 4 and a request for a discrimination signal to the teleconverter 4. FIG. After completing the first control processing 404 for the command packet 402, the accessory-side control/communication unit 435 changes the RDYA signal from L level→H level→L level (S425) to notify the camera body 2 of the receivable state. inform. The body side communication section 240 outputs the DATAB signal in synchronization with the clock signal 405 (S240). The DATAB signal at this time is a data packet 406 and includes a device ID (for example, device ID 1) assigned to the teleconverter 4. FIG. The accessory-side control/communication unit 435 that receives the data packet 406 stores the device ID1 in the storage unit 437 or causes the accessory-side control/communication unit 435 to hold the device ID 1 through the second control processing 408 .

On the other hand, the accessory-side control/communication unit 435 outputs the DATAA signal in synchronization with the clock signal 405 (S430). This DATAA signal includes a data packet 407, which includes a discrimination signal of the teleconverter 4, model name information, and the like. In this embodiment, the determination signal of the teleconverter 4 expresses the data included in the area of "DATA_1" 72 as "01", for example, indicating that it is a non-master lens. In other words, by receiving the discrimination signal (01) from the teleconverter 4, the camera body 2 detects that another device (interchangeable lens 3 in this example) is on the subject side of the currently communicating camera accessory (teleconverter 4). It can be recognized that it can be communicatively attached. The determination signal of the teleconverter 4 is stored in the storage section 437 . In addition, the camera body 2 associates the device ID 1 given to the teleconverter 4 with the model name information received from the teleconverter 4 and holds it in the in-body control section 230 .

After confirming the completion of reception of data packet 406 (S240) and the completion of transmission of data packet 406 (S430), accessory-side control/communication unit 435 changes the RDYA signal from L level to H level to L level for communication. It is abandoned (S445), and the outputs of the RDYA signal and the DATAA signal are interrupted within a predetermined time from time t11 when the signal is changed to L level (t12, S450). Furthermore, the accessory-side control/communication section 435 turns on the switch 450, that is, connects the circuit system power from the power supply circuit 452 to the interchangeable lens 3 (S460).
By connecting the circuit system power, power is supplied to the interchangeable lens 3, and the lens side control section 330 is activated at time t13. When the lens-side control unit 330 is activated, the interchangeable lens 3 can perform device ID allocation command data communication with the camera body 2, and the lens-side control unit 330 starts the accessory-side control/communication unit from time t10 to t12. Perform the same processing as the processing performed. In this embodiment, the identification signal of the interchangeable lens 3 indicates that it is the master lens, for example, the data included in the area of "DATA_1" 72 is represented by "00" or the like. In other words, by receiving the determination signal (00) from the interchangeable lens 3, the camera body 2 is not attached to the subject side of the currently communicating camera accessory (interchangeable lens 3) so that other devices can communicate with it. can recognize A determination signal for the interchangeable lens 3 is stored in the storage unit 350 . Further, the camera body 2 assigns a device ID (for example, device ID2) to the interchangeable lens 3, and associates the information received from the interchangeable lens 3 (for example, model name information) with the device ID2 assigned to the interchangeable lens 3. It is held in the in-body control unit 230 . In addition, the interchangeable lens 3 stores the assigned device ID2 in the storage unit 350 or causes the lens-side control unit 330 to hold it. Based on the determination signal, the body-side control unit 230 finds that the device to which the device ID 2 is assigned is the master lens and that another device is not mounted on the subject side in a communicable state, so the device ID allocation command data communication is terminated. .
By performing the device ID allocation command data communication in this way, the camera body 2 can allocate device IDs to all of the camera accessories that are communicatively attached, as well as acquire model name information and assign can be stored in association with the associated device ID.

In this embodiment, only the teleconverter 4 to which power is being supplied from time t10 to t12 is enabled to perform device ID allocation command data communication with the camera body 2, and requests for device ID allocation and identification signals are received. . On the other hand, the interchangeable lens 3 to which power is not supplied cannot perform device ID allocation command data communication with the camera body 2, and thus does not receive requests for device ID allocation and identification signals. Therefore, only the accessory-side control/communication unit 435 can send its own model name information and identification signal to the camera body 2 . As a result, the camera body 2 assigns the device ID 1 to the teleconverter 4, associates the information received from the teleconverter 4 (for example, model name information) with the device ID 1 assigned to the teleconverter 4, and sends the information to the body side control section 230. to hold. The body-side control unit 230 recognizes from the determination signal that the device assigned the device ID1 is a non-master lens and that another communicable device can be attached to the subject side, so it starts allocating the next device ID2. be able to.

(Normal command data communication)
Body-side control section 230, which has completed device ID allocation command data communication, performs normal command data communication after time t20. In the normal command data communication, the camera body 2 designates either the interchangeable lens 3 or the teleconverter 4 as a communication partner and performs them individually.
In the example of FIG. 7, the camera body 2 performs normal command data communication with the teleconverter 4 from time t23 to time t32, and performs normal command data communication with the interchangeable lens 3 after time t33.

When the body side communication section 240 detects that the RDYB signal has changed from L level→H level→L level, it outputs the DATAB signal in synchronization with the clock signal 401 (S130). The DATAB signal at this time includes a command packet 402, which includes instructions and requests to the teleconverter 4. FIG. Therefore, command packet 402 includes device ID 1 corresponding to teleconverter 4 .

Command packet 402 is received by lens-side communication unit 340 and accessory-side control/communication unit 435, respectively. Upon detecting that the command packet 402 includes a device ID 2 different from its own device ID 1, the lens side communication unit 340 receives the command packet 402, and detects that the command packet 402 is received for a predetermined time (t33 ), the output of the RDYL signal and the DATAL signal is interrupted (S570). Since the data length of the subsequent data packet 406 is included in the command packet 402, the predetermined blocking time can also be recognized by the lens side communication unit 340. FIG.
On the other hand, when accessory-side control/communication unit 435 receives command packet 402 and detects that device ID 2 of itself is included in command packet 402, within a predetermined time from time t21 when command packet 402 has been received, The outputs of the RDYA signal and the DATAA signal are brought into a communication ready state (t23, S530). The accessory-side control/communication unit 435 changes the RDYA signal from L level→H level→L level (S540) to notify the camera body 2 that the command data communication is possible and that the subsequent data packet 406 can be received. report to.

The body-side communication unit 240 notified by the teleconverter 4 that it is ready for reception outputs the DATAB signal in synchronization with the clock signal 405 (S140). At this time, the DATAB signal includes a data packet 406, which includes data for performing an operation instructed by the command packet 402 which the teleconverter 4 received at time t21. On the other hand, the accessory-side control/communication unit 435 outputs the DATAA signal in synchronization with the clock signal 405 (S550). At this time, the DATAA signal includes a data packet 407, which includes, for example, the magnification of the focal length of the teleconverter 4, the information indicating the optical characteristics of the lens 460, and the replacement of a predetermined interchangeable lens after attachment. The optical properties of the lens, etc., can be included.

Subsequently, when the RDYB signal changes from L level→H level→L level, the body side communication unit 240 outputs the DATAB signal in synchronization with the clock signal 401 (S130). The DATAB signal at this time contains the command packet 402 and the device ID 2 corresponding to the interchangeable lens 3 .
Command packet 402 is received by lens-side communication unit 340 and accessory-side control/communication unit 435, respectively. When accessory-side control/communication unit 435 confirms that command packet 402 includes device ID 2 that is different from its own device ID 1, accessory-side control/communication unit 435 transmits the RDYA signal and The output of the DATAA signal is cut off (t32, S570). On the other hand, when lens side communication section 340 confirms that device ID 2 of itself is included in command packet 402, lens side communication section 340 outputs the RDYL signal and the DATAL signal within a predetermined time from time t31 when command packet 402 is completely received. A communicable state is set (t33, S530). The lens-side communication unit 340 changes the RDYL signal from L level→H level→L level (S540) and notifies the camera body 2 of the receivable state.

The body-side communication unit 240 notified by the interchangeable lens 3 of the receivable state outputs the DATAB signal in synchronization with the clock signal 405 (S140). The DATAB signal at this time includes a data packet 406, which includes data and the like for the interchangeable lens 3 to perform an operation instructed by the command packet 402 that has been completely received at time t31.
On the other hand, the lens side communication section 340 outputs a DATA signal in synchronization with the clock signal 405 (S550). The DATAL signal at this time includes the data packet 407, and can include information indicating optical characteristics such as the focal length of the imaging optical system 360 of the interchangeable lens 3, information indicating the operating state of the movable portion, and the like. .

In the second usage example, the teleconverter 4 is not attached, and the interchangeable lens 3 is directly attached to the camera body 2 . In that case, the processing after time t13 in FIG. 7 is performed as the device ID allocation command data communication. Further, the processing after time t33 in FIG. 7 is performed as normal command data communication. In the case of the second usage example, only one device ID (for example, device ID 1) is assigned to the interchangeable lens 3, and the command packet sent from the camera body 2 always includes that device ID (device ID 1). be Consequently, the interchangeable lens 3 can receive all command data from the camera body 2 as a result.

When there are a plurality of, for example, two intermediate accessories between the interchangeable lens 3 and the camera body 2, the first intermediate accessory closer to the camera body 2 and the camera body 2 are connected before the interchangeable lens 3. Device ID allocation command data communication is started. Then, after completion of device ID allocation command data communication with the first intermediate accessory, device ID allocation is performed with the second intermediate accessory attached to the subject side of the first intermediate accessory (the side farther from the camera body 2). Command data communication is started. That is, the device ID allocation command data communication is performed by switching the communication partner. After the device ID allocation command data communication with all intermediate accessories attached between the camera body 2 and the interchangeable lens 3 is completed, the device ID allocation command data communication between the camera body 2 and the interchangeable lens 3 is started. be started.
That is, when there are a plurality of intermediate accessories, the same process as the process from time t10 to t12 in FIG. 7 is inserted before time t13 as the device ID allocation command data communication.

(Processing of body side control unit 230 in device ID allocation command data communication)
Next, processing of device ID assignment command data communication in the camera body 2 will be described based on FIG.
When the body-side control unit 230 performs power-on processing in response to the power-on operation, the device ID allocation command data communication of FIG. 8 is started. In step S210, the body-side control section 230 determines whether or not the signal of the LDET (B) terminal is at L level, that is, whether or not the interchangeable lens 3 is attached. When the LDET (B) terminal is at the L level, the body-side control section 230 makes an affirmative decision in step S210, proceeds to step S220, and makes a decision based on the response from the interchangeable lens 3. FIG. When the LDET (B) terminal is at the H level, the body-side control section 230 makes a negative determination in step S210, and waits for the interchangeable lens 3 to be attached while repeating the process of step S210.

In step S220, body-side control section 230 determines whether or not the RDYB signal has changed from L level→H level→L level. When the change in the RDYB signal is detected, body-side control section 230 determines that teleconverter 4 is in a receivable state, makes an affirmative determination in step S220, and proceeds to step S230. When the above change is not detected, body-side control section 230 makes a negative decision in step S220 and repeats the processing of step S220.
In step S230, the body-side control section 230 causes the command packet 402 for device ID allocation command data communication to be transmitted. In step S235, body-side control section 230 determines whether or not the RDYB signal has changed. When body-side communication unit 240 detects a change from L level→H level→L level, body-side control unit 230 determines that teleconverter 4 is in a receivable state, and makes an affirmative determination in step S235. Proceed to step S240. When the above change is not detected, body-side control section 230 makes a negative decision in step S235 and repeats the processing of step S235.
In step S240, the body-side control unit 230 causes the data packet 406 for device ID allocation command data communication to be transmitted, and receives the data packet 407 for device ID allocation command data communication from the camera accessory, and proceeds to step S245. Data packet 406 includes data indicating the device ID. On the other hand, the data packet 407 includes a camera accessory identification signal and model name information.

In step S245, body-side control section 230 determines whether or not the RDYB signal has changed. When the change of the RDYB signal from L level→H level→L level is detected, body-side control section 230 determines that the communication partner is in a receivable state, makes an affirmative determination in step S245, and proceeds to step S250. . When the above change is not detected, body-side control section 230 makes a negative decision in step S245 and repeats the processing of step S245.
In step S250, body-side control section 230 associates and holds the transmitted device ID and the model name information of the communication partner, and proceeds to step S260. That is, the body-side control unit 230 stores information linking the device ID 1 set in the data packet 406 in S240 with the communication partner "teleconverter 4".

In step S260, body-side control section 230 determines whether or not the determination signal indicates that it is the master lens. That is, body-side control section 230 determines whether the determination signal is 00 or 01. FIG. When the determination signal indicates the master lens (00), in this embodiment, other camera accessories are not attached to the subject side of the master lens in a communicable state, so they are attached in a communicable state. It can be determined that device IDs have been assigned to all camera accessories that are present. Body-side control section 230 makes an affirmative determination in step S260 and ends the device ID allocation command data communication according to FIG. After the device ID allocation command data communication, the normal command data communication in FIG. 9 is started.
If the determination signal indicates a non-master lens (01), there is a possibility that another camera accessory may be attached to the subject side of the non-master lens in a communicable state, so it is attached in a communicable state. It cannot be determined that device IDs have been assigned to all camera accessories. Body-side control unit 230 makes a negative determination in step S260 and returns to step S220. When returning to step S220, body-side control section 230 repeats the same processing as the processing described above.

(Processing of accessory-side control/communication unit 435 in device ID allocation command data communication)
Next, processing of device ID assignment command data communication in the teleconverter 4 will be described with reference to FIG.
When accessory-side control/communication section 435 is activated by the supply of circuit system power and becomes ready to receive, in step S410, it changes the RDYA signal from L level→H level→L level, and proceeds to step S420.

In step S420, the accessory-side control/communication unit 435 receives the command packet 402 of the device ID allocation command data communication from the body-side communication unit 240, and proceeds to step S425. In step S425, when the accessory side control/communication section 435 becomes ready to receive the next data packet 406, it changes the RDYA signal from L level→H level→L level, and proceeds to step S430.
In step S430, the accessory-side control/communication unit 435 receives the data packet 406 of the device ID allocation command data communication from the body-side communication unit 240, and transmits the data packet 407 to the body-side communication unit 240. Then, the process proceeds to step S440. move on.

In step S440, the accessory-side control/communication section 435 stores the device ID assigned from the camera body 2 to the teleconverter 4 by the data packet 406 received in step S430 in the storage section 437, and the process proceeds to step S445.
In step S445, the accessory-side control/communication section 435 completes the storage of the device ID as the first control processing 404, and when it becomes ready to receive, changes the RDYA signal from L level→H level→L level, and Proceed to S450.

In step S450, the accessory-side control/communication unit 435 cuts off the output of the upper RDYA signal and the DATAA signal (puts them in a high impedance state), and proceeds to step S460. In step S460, the accessory-side control/communication unit 435 turns on the switch 450, that is, supplies circuit system power to the interchangeable lens 3, and terminates the device ID assignment command data communication shown in FIG. After the device ID allocation command data communication, the normal command data communication in FIG. 9 is started.

(Processing of lens side control unit 330 in device ID allocation command data communication)
Next, based on FIG. 8, processing of device ID allocation command data communication in the interchangeable lens 3 will be described.
When the lens-side control unit 330 is activated by the supply of the circuit system power and enters a receivable state, the lens-side communication unit 340 changes the RDYL signal from L level→H level→L level in step S310. proceed to

In step S320, the lens side control section 330 receives the command packet 402 of the device ID allocation command data communication from the body side communication section 240 by the lens side communication section 340, and proceeds to step S325. In step 325, when the lens side control section 330 becomes ready to receive the next data packet 406, the lens side communication section 340 causes the RDYL signal to change from L level→H level→L level, and the process proceeds to step S330. .
In step S<b>330 , lens-side control section 330 receives data packet 406 for device ID allocation command data communication from body-side communication section 240 through lens-side communication section 340 , and transmits data packet 407 to body-side communication section 240 . Then, the process proceeds to step S340.

In step S340, the lens-side control unit 330 stores the device ID assigned to the interchangeable lens 3 from the camera body 2 by the data packet 406 received in step S330 in the lens-side storage unit 350 as the first control process 404. The process proceeds to step S345.
In step S345, the lens-side control unit 330 completes the storage of the device ID, and when the device ID is ready for reception, the lens-side communication unit 340 changes the RDYL signal from L level→H level→L level so that the device in FIG. End the ID allocation command data communication. After the device ID allocation command data communication, the normal command data communication in FIG. 9 is started.

(Processing of body-side control unit 230 in normal command data communication)
Next, processing of normal command data communication in the camera body 2 will be described with reference to FIG.
In step S110, body-side control section 230 determines the communication partner (that is, device ID), and proceeds to step S120. At this time, the device ID of the communication partner is held in the body side control section 230 . The body-side control unit 230 uses the teleconverter 4 as a communication partner when giving instructions or requests to the teleconverter 4, such as driving control within the teleconverter 4 or error checking within the teleconverter 4, for example. Determine ID1. Further, for example, instructions and requests to the interchangeable lens 3 such as initialization such as moving the lens 361 to the initial position by the lens driving unit 370, driving control of the lens 361 by the lens driving unit 370, and error check in the interchangeable lens 3 are performed. , the device ID 2 is determined because the interchangeable lens 3 is the communication partner.

In step S120, body-side control unit 230 determines whether or not the RDYB signal is at H level. That is, when the body-side control unit 230 detects that the RDYB signal has changed from the L level to the H level to the L level after finishing the device ID allocation processing and the second control processing in the camera accessory, the body control unit 230 performs step S120. An affirmative determination is made and the process proceeds to step S130. When the above change is not detected, body-side control section 230 makes a negative decision in step S120 and repeats the processing of step S120.

In step S130, body-side control section 230 transmits command packet 402 for normal command data communication, and proceeds to step S135. The command packet 402 at this time includes data specifying the device ID. In step S135, body-side control section 230 determines whether or not the RDYB signal has changed. When the change of the RDYB signal from L level→H level→L level is detected, body-side control section 230 determines that the communication partner is in a receivable state, makes an affirmative determination in step S135, and proceeds to step S140. . When the above change is not detected, body-side control section 230 makes a negative decision in step S135 and repeats the processing of step S135.
In step S140, the body-side control section 230 causes the data packet 406 for normal command data communication to be transmitted, and receives the data packet 407 for normal command data communication from the camera accessory of the communication partner, and proceeds to step S145.
In step S145, body-side control section 230 determines whether or not the RDYB signal has changed. When the change of the RDYB signal from L level→H level→L level is detected, body side control section 230 determines that the communication partner is in a receivable state, makes an affirmative determination in step S145, and proceeds to step S150. . When the above change is not detected, body-side control section 230 makes a negative decision in step S145 and repeats the processing of step S145.

In step S150, body-side control section 230 determines whether or not to perform end processing. For example, when the power-off operation is performed, the body-side control unit 230 makes an affirmative determination in step S150, performs a predetermined turn-off process, and ends the normal command data communication shown in FIG. It is assumed that the device ID stored in the storage unit 235 is erased during the off processing.
If the end process is not to be performed, body-side control section 230 makes a negative determination in step S150 and returns to step S130. After returning to step S130, the body-side control unit 230 repeats the same processing as described above. Note that the body-side control unit 230 may perform step S110 of determining the communication partner before step S130.

(Processing of intermediate accessory control/communication section 435 and lens side control section 330 in normal command data communication)
Next, processing of normal command data communication in the camera accessory will be described with reference to FIG. Hereinafter, the accessory-side control/communication unit 435 or the lens-side control unit 330 will be collectively referred to as a "camera accessory control unit".
In step S510, the control unit of the camera accessory receives the command packet 402 for normal command data communication from the body-side control unit 240, and proceeds to step S520.

In step S520, the control unit of the camera accessory determines whether or not the device ID included in the command packet 402 matches its own device ID. If the command packet 402 contains its own device ID, the control unit of the camera accessory makes an affirmative decision in step S520 and proceeds to step S530. If the command packet 402 does not contain the device ID of itself, the control unit of the camera accessory makes a negative decision in step S520 and proceeds to step S570.

If the command packet 402 is addressed to itself, the control unit of the camera accessory makes the output of the RDYA signal and DATAA signal or the output of the RDYL signal and DATAL signal ready for communication in step S530, and proceeds to step S540. . In step S540, when the control unit of the camera accessory determines that there is no error in the reception of the command packet 402, it changes the RDYA signal or RDYL signal from L level→H level→L level, and proceeds to step S545. In step S545, the control unit of the camera accessory starts the first control process 404 based on the command packet 402 and proceeds to step S550.

In step S550, the control unit of the camera accessory receives data packet 406 from body-side control unit 240 and transmits data packet 407 to body-side control unit 240, and proceeds to step S560.
In step S560, when the controller of the camera accessory determines that there is no error in receiving the data packet 406, it changes the RDYA signal or RDYL signal from L level→H level→L level, and proceeds to step S565. In step S565, the control unit of the camera accessory starts the second control process 408 based on the control contents of the data packet 406, and returns to step S510.

If the command packet 402 does not contain its own device ID, the control unit of the camera accessory makes a negative decision in step S520 and proceeds to step S570. In step S570, the control unit of the camera accessory cuts off the output of the RDYA signal or RDYL signal and the DATAA signal or DATAL signal, and returns to step S510.

(Third usage example)
In the first use example and the second use example, when only the non-master lens is attached to the camera body 2, the potential of the LDET (B) terminal remains at the potential of the power supply V33 and does not decrease, and the camera body 2 is the camera. It was decided not to detect when an accessory is attached. In addition, in the first usage example and the second usage example, the body-side control unit 230 detects a drop in the potential of the LDET (B) terminal and uses a lens attachment/detachment detection pin (not shown) provided on the body-side mount 210 . It is configured to detect the attachment of the interchangeable lens 3 by the attachment detection.
However, the camera body 2 may detect that a camera accessory is attached even when the non-master lens is attached and the master lens is not attached.
Hereinafter, a usage example in which the power is turned on while the teleconverter 4 is attached to the camera body 2 and then the interchangeable lens 3 is attached is referred to as a third usage example. In the third example of use, the device ID allocation command data communication from step S220 onward may be started when the power of the camera body 2 is turned on and before the interchangeable lens 3 is attached. In this way, with only the teleconverter 4 attached to the camera body 2, the device ID is assigned to the teleconverter 4 by the processing from time t10 to time t12, and then after the interchangeable lens 3 is attached, 3, the process from time t12 to time t20 may be performed to allocate the device ID.

<Explanation of hotline communication>
The body-side control section 230 performs hotline communication with the master lens. The master lens (interchangeable lens 3 in this embodiment) has a moving member inside, and transmits the position and movement status of the moving member by hotline communication independent of command data communication. In hotline communication, a data signal (HDATA signal) and a clock signal (HCLK signal) are unidirectionally transmitted from the lens side control section 330 to the body side control section 230 .

In hotline communication, when an instruction to start hotline communication is sent from the camera body 2 to the interchangeable lens 3 by command data communication, an instruction to end hotline communication is sent from the camera body 2 to the interchangeable lens 3 by command data communication. Until then, the hotline data is transmitted from the lens side communication section 340 to the body side communication section 240 irrespectively (independently) of the command data communication. The hotline data transmitted from the lens-side communication unit 340 to the body-side communication unit 240 is, for example, information about the state of the interchangeable lens 3, such as positional information of the focusing lens of the lens 361, positional information of the shake correction lens, focusing lens can include information indicating the control state of This information is shown as lens signal 503 in FIG. 5, described below.

FIG. 5 is a diagram illustrating the timing of hotline communication performed between the body-side communication section 240 and the lens-side communication section 340. As shown in FIG. When the lens-side control unit 330 receives a command to start hotline communication through command data communication (T6), the lens-side control unit 330 starts data generation processing 501 regarding lens information. The generation process 501 is a process of acquiring information indicating the state of the interchangeable lens 3 at a sampling period of 1 millisecond, for example, and generating a signal containing the acquired information, that is, a lens signal 503 .

When the lens-side control unit 330 completes the generation of the lens signal 503 (T7), the lens-side communication unit 340 outputs the clock signal 502 from the HCLK(L) terminal. Thereby, the clock signal 502 is transmitted from the interchangeable lens 3 to the camera body 2 . The frequency of clock signal 502 is, for example, 2.5 MHz.

The lens side communication section 340 outputs a lens signal 503 as an HDATA signal in synchronization with the clock signal 502 . In FIG. 5, the lens signal 503 is indicated by switching between H level and L level. When the transmission of the lens signal 503 is completed (T8), the lens side communication section 340 stops outputting the clock signal 502 and returns to time T6. The lens-side communication unit 340 repeats the time T6 to T8 as one hotline cycle.
The lens side communication unit 340 performs the generation process 501 and the lens signal at regular intervals (for example, 1 millisecond) until an instruction to end communication (also referred to as an instruction to stop transmission) is transmitted from the camera body 2 by command data communication. 503 is repeated. The time from time T7 to time T8 shall not exceed 80% of the time from time T6 to time T8. That is, the time required for transmitting the lens signal 503 is about 75% of one hotline communication, and the data length of the lens signal 503 is set so as not to exceed 80%. Also, the lens-side control unit 330 may perform the generation processing 501 independently of the HCLK signal and the HDATA signal. In that case, the generation process 501 does not necessarily have to be performed between T6 and T7.

Since two systems of communication can be performed independently by the above-described command data communication and hotline communication, each communication can be executed in parallel. That is, the body-side control section 230 and the lens-side control section 330 can start and end hotline communication during command data communication. It is also possible to perform command data communication while performing hotline communication. Therefore, the body-side control section 230 can continuously acquire information about the interchangeable lens 3 through hotline communication even during command data communication. In addition, since the information about the interchangeable lens 3 can be continuously obtained through hotline communication, it is possible to suppress the adverse effect of sending and receiving long data through command data communication. Also, since the body-side control unit 230 has hotline communication, it can send various instructions and requests to the interchangeable lens 3 at arbitrary timing, and can receive information from the interchangeable lens 3 at arbitrary timing. can.

According to the embodiment described above, the following effects are obtained.
(1) The camera body 2 is detachable from a camera accessory that receives light from a subject, and includes a body side terminal and a body side communication section 240 that communicates with at least one of the attached camera accessories. The body-side communication unit 240 can mount another device (for example, the interchangeable lens 3) that can communicate with the camera body 2 on the front side (subject side) of the teleconverter 4 via the communication terminal among the body-side terminals. The teleconverter 4 is requested to send a determination signal indicating whether or not Since it is configured in this way, it is possible to acquire a determination signal indicating whether or not a camera accessory is present in front of the communicating device from the communicating device. The discrimination signal is information for discriminating whether it is a master lens or a non-master lens, and in this embodiment, indicates whether or not another device can be attached to the subject side of the device in a communicable manner. defined as information.
Since the camera accessory transmits a discrimination signal for discriminating whether it is the master lens or the non-master lens, the camera body 2 does not need to provide a dedicated terminal for discriminating whether it is the master lens or the non-master lens, and , there is no need to determine whether it is a master lens or a non-master lens from the model name information of the camera accessory. Since it is not necessary to provide a terminal only for distinguishing between the master lens and the non-master lens, it contributes to miniaturization of the camera body 2 and the mount section of the camera accessory. Also, the number of terminals of the master lens and the number of terminals of the non-master lens can be the same, which contributes to downsizing of the mount section. In addition, since the camera body 2 does not need to determine whether it is a master lens or a non-master lens from the model name information of the camera accessory, it is also necessary to store all the model name information of the camera accessories that can be attached to the camera body 2. Therefore, it is possible to determine whether a camera accessory developed and released after the camera body 2 is a master lens or a non-master lens.

(2) The camera body 2 has a storage section that stores a device ID for identifying the interchangeable lens 3 and the teleconverter 4 . With this configuration, the device IDs of the camera accessories connected to the camera body 2 can be appropriately managed.

(3) The body-side communication unit 240 instructs the interchangeable lens 3 with the device ID 2 in the command packet 402 and instructs the teleconverter 4 with the device ID 1 in the command packet 402 . Since the device ID assignment command data communication and the normal command data communication are not performed in parallel, the device ID can be appropriately assigned to each communication partner. A communication partner can be specified. In command data communication, the control unit of the camera accessory transmits data packet 407 in parallel with receiving data packet 406 . As described above, the command packet 402 is unidirectional, but the data packet is bidirectional, so that data communication means from the camera accessory to the camera body 2 can be secured by command data communication.
Further, in the present embodiment, the device ID is assigned each time the power is turned on or each time the accessory is attached/detached, and is assigned in the order in which it is attached to the camera body 2 . Therefore, the camera body 2 does not always assign the same device ID to a specific camera accessory.

(4) The body-side communication unit 240 performs normal command data communication using the device ID. Since it is configured in this way, it is possible to designate the party to be instructed by the device ID and appropriately send the instruction. Here, if the device ID is not used, it is necessary to determine within the camera accessory whether or not the instruction from the camera body 2 is addressed to itself. may increase the time it takes for the to receive the instructions. If the device ID is not used, the camera accessory may not be able to determine whether or not the instruction from the camera body 2 is addressed to itself. There is also the problem of not being able to However, according to this embodiment, a desired camera accessory can be made to receive instructions at appropriate timing.

(5) The body-side communication unit 240 causes the determination signal indicating whether or not another device capable of communicating with the camera body 2 to be attached to the front side (subject side) of the camera accessory indicates that it cannot be attached. , the device ID allocation command data communication ends. After completing the device ID allocation command data communication, the body-side control unit 230 instructs the camera accessory to start initialization processing or the like by normal command data communication. The initialization process is, for example, a process of moving a driven part such as the lens 361 to an initial position.
In the present embodiment, the device ID assignment command data communication is terminated after receiving the discrimination signal indicating that no other device can be attached to the front side. It is possible to assign a device ID to all. Since normal command data communication can be started after assigning device IDs to all attached camera accessories, communication using device IDs can be performed for all camera accessories attached in a communicable manner. can be done.

(6) When the determination signal indicates that another device capable of communicating with the camera body 2 can be attached to the front side (subject side) of the camera accessory, the body side communication section 240 performs the communication via the camera accessory. to communicate with other devices. With this configuration, the interchangeable lens 3 can communicate with the camera body 2 via the teleconverter 4, and it is necessary to separately provide a terminal for communication with the camera body 2 and a terminal for communication with the teleconverter. It is possible to reduce the size of the mount part.

(7) The body side communication section 240 instructs the device ID of the interchangeable lens 3 via the terminal of the teleconverter 4 . With this configuration, even if an intermediate accessory is attached, the device ID can be appropriately notified to the camera accessory.

(8) After starting the device ID allocation command data communication, the body-side communication unit 240 instructs the camera accessory (the teleconverter 4 in this embodiment) to which the device ID is to be assigned first, with the device ID 1 as the device ID. Next, the device ID2 as the device ID is instructed to the camera accessory (the interchangeable lens 3 in this embodiment) to which the identifier is assigned. The device ID 1 is for the teleconverter 4 to recognize the instruction addressed to itself and to distinguish it from the instruction addressed to the interchangeable lens 3 . The device ID 2 is for the interchangeable lens 3 to recognize an instruction addressed to itself and to distinguish it from an instruction addressed to the teleconverter 4 . In this manner, since the camera accessories are configured to be assigned different device IDs in order from the camera accessory closer to the camera body 2, the device IDs can be appropriately assigned to the plurality of communication partners.

(9) The camera body 2 includes a power supply unit 250 that supplies power to the power supply circuit 452 of the attached teleconverter 4 and the power supply circuit 352 of the interchangeable lens 3 . With this configuration, it is possible to appropriately supply power to a plurality of communication partners from the single power supply section 250 of the camera body 2 .

(10) A camera accessory into which light from a subject is incident is configured to be attachable to and detachable from the camera body 2 . For example, the teleconverter 4 includes an accessory-side control/communication unit 435 that communicates with the camera body 2, and another camera accessory (for example, the interchangeable lens 3) that can communicate with the camera body 2 on the front side of the teleconverter 4 (i.e., the subject side). The accessory-side control/communication unit 435 sends the determination signal to the camera body 2 . Also, the interchangeable lens 3 indicates that the lens-side communication unit 340 that communicates with the camera body 2 and other camera accessories that can communicate with the camera body 2 cannot be mounted on the front side (subject side) of the interchangeable lens 3. A lens-side storage unit 350 that stores a determination signal (for example, 00) is provided, and the lens-side communication unit 340 sends the determination signal to the camera body 2 . With this configuration, the camera body 2 can easily recognize whether or not another camera accessory can be communicatively attached to the front side of the camera accessory.

(11) A camera accessory that receives light from a subject is detachable from the camera body 2 and has a communication unit that communicates with the camera body 2 . The camera accessory stores a determination signal indicating whether or not another device capable of communicating with the camera body 2 can be mounted on the object side of the camera accessory, and the communication unit transmits the determination signal to the camera body 2 . In other words, the master lens stores a determination signal indicating that another device that can communicate with the camera body 2 is not attached to the subject, and the non-master lens stores a determination signal indicating that another device that can communicate with the camera body 2 is not attached to the subject. It stores a determination signal indicating that it can be worn. With this configuration, the camera accessory can appropriately inform the camera body 2 of information indicating whether or not there is another camera accessory communicably present on the subject side. Since the discrimination signal is stored for each camera accessory, there is an effect that it is not necessary to store whether the camera body is a master lens or a non-master lens for each camera accessory.

(12) Each camera accessory has a storage unit that stores a device ID for distinguishing it from other camera accessories. Since it is configured in this way, the camera accessory can appropriately retain its device ID and receive instructions from the camera body 2 appropriately.

(13) The camera accessory has an identification unit that identifies whether or not the command packet 402 transmitted from the camera body 2 contains its own device ID stored in the storage unit (accessory side in the case of the teleconverter 4). A control/communication unit 435 and a lens-side control unit 330 in the case of the interchangeable lens 3 are provided. With this configuration, it is possible to appropriately determine whether the command packet 402 transmitted from the camera body 2 is addressed to itself or to another person.

(14) When the command packet 402 contains its own device ID, the camera accessory determines that the command data communication is addressed to itself and receives the data packet 406 . If a data packet 406 including a device ID different from its own device ID is received, the drive instruction from the camera body 2 may not be executed normally by the intended camera accessory, or an unintended camera accessory may be transferred to the camera body. 2, the data packet 407 may be transmitted. Since this embodiment is configured as described above, it is possible to appropriately receive the command packet 402 addressed to itself and the subsequent data packet 406 transmitted from the camera body 2 .

(15) If the command packet 402 does not contain its own device ID, the camera accessory puts the communication terminal into a high impedance state and does not receive the data packet 406 . With this configuration, it is possible to avoid receiving the data packet 406 when an instruction or request sent from the camera body 2 is addressed to another person.

(16) The camera accessory has a lens side terminal on the side opposite to the subject side (imaging surface side). The accessory-side control/communication section 435 and the lens-side communication section 340 communicate with the camera body 2 via the lens-side terminal.

(17) The teleconverter 4 has a body side terminal for communicating with the interchangeable lens 3 on the subject side, and a lens side terminal on the side opposite to the subject side in the optical axis O direction. Accessory-side control that can switch the signal line that connects between A communication unit 435 is provided. With this configuration, for example, the RDYL signal output from the interchangeable lens 3 and the RDYA signal output from the teleconverter 4 can be prevented from colliding on the signal line.

(18) The teleconverter 4 and the interchangeable lens 3 have an optical system for passing light from the object side.

(19) The teleconverter 4 includes a plurality of lens-side terminals provided on the rear terminal holding portion 422 on the camera body 2 side, a plurality of body-side terminals provided on the front terminal holding portion 423 on the interchangeable lens 3 side, and a lens terminal holding portion 423 on the interchangeable lens 3 side. At least one feeding signal line for connecting at least one of the side terminals and at least one of the body side terminals, and a switch 450 for opening and closing the feeding signal line.
According to this embodiment, the number of connection terminals (11) between the camera body 2 and the interchangeable lens 3 is equal to the number of connection terminals (11) between the teleconverter 4 and the interchangeable lens 3, and the terminals No need to increase the number.
The camera body 2 to which the teleconverter 4 is attached feeds power to the teleconverter 4 through the V33 (B) terminal connected to the body side terminal group and the power feeding signal line provided with the switch 450 in the teleconverter 4. A power supply unit 250 is provided. With this configuration, the body-side control unit 230 supplies power from the camera body 2 to the teleconverter 4 when the switch 450 is open, and supplies power from the camera body 2 to the teleconverter 4 and the interchangeable lens 3 when the switch 450 is closed. power can be supplied to

(20) The camera body 2 further includes a body-side communication section 240 that communicates with the accessory-side control/communication section 435 via communication terminals of the body-side terminal group. When the body-side communication unit 240 receives the change of the RDYA signal or the RDYL signal from L level→H level→L level, the device ID allocation command data communication is started. With this configuration, the device ID can be assigned from the camera body 2 to the camera accessory after waiting for the camera accessory receiving power to become communicable.

(21) In the first usage example, when the second control processing 408 is completed in the device ID allocation command data communication and the switch 450 is closed, the power supply unit 250 is replaced via the V33 (B) terminal for power supply. Power is supplied to the lens 3. Furthermore, the body-side communication unit 240 communicates with the lens-side communication unit 340 via the communication terminal, and changes the RDYL signal (L level) indicating whether command data communication from the supplied interchangeable lens 3 is possible. →H level →L level), a command packet 402 including the device ID is sent to the interchangeable lens 3 . With this configuration, a device ID can be assigned from the camera body 2 to the interchangeable lens 3 after waiting for the interchangeable lens 3 that has received power to become communicable.

(22) The camera accessory attached to the camera body 2 has a communication section that communicates with the body-side communication section 240 via a communication terminal. The communication unit of the camera accessory switches the RDYL signal or RDYA signal, DATAL signal or DATAA signal to a communication abandoned state (high impedance state) or a communication enabled state. With this configuration, for example, the RDYL signal output from the interchangeable lens 3 and the RDYA signal output from the teleconverter 4 can be prevented from colliding on the signal line.

(23) The communication unit of the camera accessory puts the input units (communication terminals DATAB, CLK) for inputting the DATAB signal and the CLK signal from the camera body 2 into a communicable state. With this configuration, the interchangeable lens 3 and the teleconverter 4 can appropriately receive the CLK signal and DATAB signal output from the camera body 2 .

(24) The communication unit of the camera accessory can communicate with the output unit (communication terminals RDY(L), DATA(L)) when the command packet 402 including the device ID addressed to itself is input from the camera body 2. switch to state. Since it is configured in this manner, it waits for the command packet 402 including the device ID addressed to itself to be input, and then switches the output section to the communicable state. Therefore, for example, the signals (RDYL, DATAL) output from the interchangeable lens 3 and the signals (RDYA, DATAA) output from the teleconverter 4 can be appropriately prevented from colliding on the signal line. can.

(25) When the command packet 402 including the device ID addressed to another person is input from the camera body 2, the communication unit of the camera accessory does not receive the command packet 402 including the device ID addressed to oneself. Sometimes, the output section (communication terminals RDY(L), DATAL(L)) is switched to the communication abandoned state (high impedance state). Since it is configured in this way, for example, the collision on the signal line between the signals (RDYL, DATAL) output from the interchangeable lens 3 and the signals (RDYA, DATAA) output from the teleconverter 4 can be avoided. Can be properly avoided.

(26) The teleconverter 4 mounted between the camera body 2 and the interchangeable lens 3 has a lens-side terminal provided in the rear-side terminal holding portion 422 on the camera-body 2 side and a front-side terminal holding portion on the interchangeable lens 3 side. 423, a plurality of signal lines that connect the lens side terminals and the body side terminals, and a switch 450 that is provided on one of the signal lines and opens and closes the signal line. With this configuration, for example, when the switch 450 is open, the signal line from the camera body 2 to the interchangeable lens 3 is cut off and only the signal line from the camera body 2 to the teleconverter 4 is turned on. is closed, the signal line from the camera body 2 to the interchangeable lens 3 can be conducted through the teleconverter 4 .

(27) In the teleconverter 4 , the switch 450 is provided on at least the signal line supplied from the power supply section 250 of the camera body 2 among the plurality of signal lines. With this configuration, power can be supplied from the camera body 2 to the teleconverter 4 when the switch 450 is open. Further, when the switch 450 is closed, power can be supplied from the camera body 2 to the teleconverter 4 and the interchangeable lens 3 .

(28) In the teleconverter 4, the switch 450 is a normally open contact. Therefore, in the initial state when the switch 450 is open, power is supplied only from the camera body 2 to the teleconverter 4, and when the switch 450 is closed, the camera body 2 is closed. can supply power to the teleconverter 4 and the interchangeable lens 3.

(29) In the teleconverter 4, the accessory-side control/communication unit 435 puts the output unit for the signal lines for communication (the signal lines for the RDYA signal and the DATAA signal) into a communication abandonment state (high impedance state), and then switches 450 close. With this configuration, for example, even if the RDYL signal is output to the signal line for communication from the interchangeable lens 3 supplied by closing the switch 450, the RDYL signal is output from the output section of the teleconverter 4. Collision on the signal and signal line can be avoided.

(30) The camera body 2 assigns device IDs to all camera accessories that are communicably attached, designates the device IDs in normal command data communication, and sends the command packet 402 and data packet 406 to the body. Send from the side communication unit 240 . With this configuration, the camera body 2 can specify a communication partner and communicate with a device to which a device ID matching the specified device ID is assigned.

The following modifications are also within the scope of the present invention, and it is also possible to combine one or more of the modifications with the above-described embodiments.
Although the camera body 2 of this embodiment is of the mirrorless type, it may be of the single-lens reflex type.
The storage unit of this embodiment may be volatile or non-volatile. The device ID may be held and temporarily stored in the control unit (body-side control unit 230, accessory-side control/communication unit 435, lens-side control unit 330). , 350) may be temporarily stored. The time for storing the device ID should include at least the time during which the accessory is attached, and there is no need to continue to store the device ID after removing the accessory or turning off the power.
In this embodiment, the lens drive unit 370 moves the focusing lens along the direction of the optical axis O, but it can be changed as appropriate. When zoom lenses are included in the plurality of lenses 361 , the zoom driving section may be included as the lens driving section 370 . Further, when a plurality of lenses 361 include a shake correction lens for suppressing the influence of shake caused by camera shake or the like, the lens drive unit 370 may include the shake correction lens drive unit.
In the present embodiment, the drive system voltage is supplied only to the interchangeable lens 3 and not to the teleconverter 4 , but the drive system power may be supplied to the teleconverter 4 .
In this embodiment, one command packet 402 contains an instruction to allocate a device ID to a camera accessory and an instruction to transmit a determination signal to the camera accessory, but it may be divided into two command packets. . In this case, the camera accessory separately prepares a data packet 407 containing model name information and a data packet 407 containing a discrimination signal.
In this embodiment, device IDs are assigned to all camera accessories attached to the camera body 2 in the order of connection to the camera body 2 (in order from the camera accessory closest to the camera body 2). This is not the case. In this embodiment, when the teleconverter 4 and the interchangeable lens 3 are attached to the camera body 2 as shown in FIGS. , a device ID is assigned to the interchangeable lens 3 . In this order, after the teleconverter 4 is attached alone to the camera body 2, the interchangeable lens 3 is attached to the teleconverter 4 integrated with the camera body 2; This is common (unchanged) in the case where the teleconverter 4 integrated with the interchangeable lens 3 is attached to the camera body 2 after the interchangeable lens 3 is attached.
In this embodiment, the power-on process is performed and the device ID allocation command data communication is started in response to the power-on operation, but this is not the only option.
Although the teleconverter 4 has been described as an example of the non-master lens in this embodiment, the non-master lens is not limited to the teleconverter 4 . For example, a wide converter, a close-up ring, or the like may be used. That is, the teleconverter 4 may take any form as long as it is an intermediate accessory that is mounted between the camera body 2 and the master lens. A lens hood, a front converter, and the like can be attached to the subject side of the master lens, but since they do not communicate with the camera body 2, they are not considered to be attached in a communicable state. Another example of the master lens is an adapter that converts the communication standard to the camera body 2 . The adapter is attached with an interchangeable lens conforming to another communication standard on the subject side, but in communication with the camera body 2, the adapter converts the communication standard and transmits instructions to the interchangeable lens conforming to the other communication standard. Therefore, from a communication point of view, the adapter may be the master lens.
It should be noted that being able to be attached in a communicable manner means being capable of receiving instructions from the camera body 2 and responding appropriately to those instructions. Therefore, members such as lens caps and hoods that can be physically attached to the subject side of camera accessories are not "camera accessories that can be attached in a communicable manner" in this embodiment. Also, an interchangeable lens conforming to another communication standard can be attached to the camera body 2 via a mount adapter. Unable to respond, the mount adapter needs to convert instructions from the camera body 2. Therefore, in the present embodiment, the interchangeable lens conforming to the other communication standard is not considered to be a "camera accessory that can be communicatively attached".
In this embodiment, the accessory-side control/communication unit 435 is not connected to the HCLK(B) terminal, HCLK(L) terminal, HDATA(B) terminal, and HDATA(L) terminal. Therefore, when viewed from the camera body 2, the other party of hotline communication is only the interchangeable lens 3, and a one-to-one relationship is maintained. Therefore, the device ID of the communication partner is not specified for hotline communication, but this is not the only option.
In this embodiment, one teleconverter 4 is attached as an intermediate accessory, but a plurality of intermediate accessories may be attached. Also, an upper limit (eg, two) may be provided for the number of intermediate camera accessories.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other aspects conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1... Camera system, 2... Camera body, 3... Interchangeable lens, 4... Accessory, 210... Body side mount, 230... Body side control part, 235... Storage part, 240... Body side communication part, 270... Signal processing part, 310... Lens side mount 330... Lens side control section 340... Lens side communication section 350... Lens side storage section 352, 452... Power supply circuit 360... Imaging optical system 402... Command packet 406, 407... Data Packet 412 Rear mount 413 Front mount 435 Control/communication unit 437 Storage unit 450 Switch 460 Lens

Claims (14)

A camera system having at least one accessory and a camera body communicable with the accessory,
a camera body with a body-side mount;
an accessory comprising: an accessory-side mount detachable from the body-side mount; and a receiver for receiving an instruction signal transmitted from the camera body;
with
the instruction signal includes identification information and an instruction from the camera body ;
The camera system , wherein the identification information is information for identifying an accessory attached to the body-side mount and capable of communicating with the camera body . A camera system having at least one accessory and a camera body communicable with the accessory,
a camera body with a body-side mount;
an accessory comprising: an accessory-side mount detachable from the body-side mount; and a receiver for receiving an instruction signal transmitted from the camera body;
with
the instruction signal includes identification information and an instruction from the camera body;
The camera system, wherein the identification information is information for specifying one communication partner among the accessories attached to the body-side mount. A camera system having at least one accessory and a camera body communicable with the accessory,
a camera body with a body-side mount;
an accessory comprising: an accessory-side mount detachable from the body-side mount; and a receiver for receiving an instruction signal transmitted from the camera body;
with
the instruction signal includes identification information and an instruction from the camera body;
The camera system, wherein the identification information is information indicating an order of attachment from the body-side mount. 3. The camera system according to claim 1 or 2,
The camera system, wherein the identification information is information specifying the accessory that executes the instruction. A camera system according to any one of claims 1 to 4 , wherein
The camera system, wherein the accessory includes an execution unit capable of executing an instruction from the camera body. A camera system according to any one of claims 1 to 5 , wherein
The camera system, wherein the receiving unit determines whether or not to receive the instruction according to the identification information. A camera system according to any one of claims 1 to 6 , wherein
the instruction signal includes a command packet and a data packet;
The camera system, wherein the identification information is included in the command packet. A camera system having at least one accessory and a camera body communicable with the accessory,
a camera body with a body-side mount;
An accessory comprising: an accessory-side mount that is detachable from the body-side mount; and a receiver that receives a signal including identification information for identifying the camera accessory and an instruction from the camera body, which is transmitted from the camera body. and,
with
The camera system, wherein the identification information indicates the order of attachment from the body-side mount. a camera body with a body-side mount;
an accessory comprising: an accessory-side mount detachable from the body-side mount; and a receiver for receiving an instruction signal transmitted from the camera body;
A camera system, wherein the instruction signal includes identification information for identifying an accessory attached to the camera body. A camera system according to any one of claims 1 to 9 , wherein
A camera system in which the accessory is an interchangeable lens provided with an optical system on which light from a subject is incident. A camera system according to any one of claims 1 to 10 , wherein
A camera system in which the accessory is directly or indirectly attachable to and detachable from the body-side mount. A camera system according to any one of claims 1 to 11 , wherein
A camera system in which the accessory transmits information to the camera body indicating that another camera accessory capable of communicating with the camera body cannot be mounted on the subject side of the accessory. A camera system according to any one of claims 1 to 9 , wherein
A camera system in which the accessory is an intermediate accessory detachable between the camera body and the interchangeable lens. A camera system according to any one of claims 1 to 10 , wherein
The camera system, wherein the accessory comprises a first accessory directly attached to the body-side mount, and a second accessory attached to the first accessory and capable of communicating with the camera body.

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