Accessory device, camera equipment and control method thereof

Abstract

The present invention provides an accessory device, an imaging apparatus, and a control method thereof. A communication control unit of an interchangeable lens (100) transmits information about distance information corresponding to a focus lens position to a camera body (200) to which the interchangeable lens unit is attached. The camera body (200) includes a display unit and displays information received from the interchangeable lens (100) on a display unit (206).

Description

[0001] (This application is a divisional application of an application filed on June 20, 2019, with application number 201910538566.2 and entitled “Accessory device, camera apparatus, and control method thereof.”) Technical Field

[0002] The present disclosure relates to communication with an accessory device regarding information to be displayed at a display unit of an imaging apparatus. Background Art

[0003] There is known a technology in which a camera displays information about a lens at a display unit (eg, a display) included in the camera.

[0004] Japanese Patent Application Laid-Open No. 2010-2823 discusses a technique of displaying information on the focal position (object distance) of a lens at a display unit of a camera instead of a display member of a lens barrel of the lens.

[0005] Furthermore, Japanese Patent Application Laid-Open No. 2007-72407 discusses a technique of displaying position information about a focus lens of a lens at a camera and also displaying depth information at the camera.

[0006] In the conventional techniques discussed in Japanese Patent Application Laid-Open No. 2010-2823 and Japanese Patent Application Laid-Open No. 2007-72407, the lens barrel of the lens does not need to include a display member. Therefore, it is possible to achieve an effect that is conducive to the miniaturization and lightweighting of the lens. However, Japanese Patent Application Laid-Open No. 2010-2823 and Japanese Patent Application Laid-Open No. 2007-72407 do not discuss the specific content of the data to be transmitted from the lens to the camera for displaying the focal length information and the ratio on the display unit included in the camera. Therefore, Japanese Patent Application Laid-Open No. 2010-2823 and Japanese Patent Application Laid-Open No. 2007-72407 have the following problems: for example, it is impossible to display an indicator of distance information based on the specification differences between interchangeable lenses (e.g., wide-angle lens and telephoto lens) or the specification differences between cameras (e.g., the number of pixels of the display unit of the camera). Summary of the Invention

[0007] The present disclosure is directed to providing an accessory device and an imaging apparatus capable of appropriately displaying information according to an interchangeable lens at a camera display unit, and a control method of the accessory device and the imaging apparatus.

[0008] According to an embodiment of the present disclosure, there is provided an accessory device that is attachable to an imaging device including a display unit and includes a focus lens for changing a focus lens position, the display unit including a display area for displaying distance information corresponding to the focus lens position, the accessory device including: a communication control unit configured to control communication with the imaging device via the communication unit, wherein the communication control unit sends: (A) information indicating the number of distance information displayed in association with the display area; (B) information indicating the number of distance information indicated by the number; (C) information indicating the position of each distance information relative to the display area; and (D) information indicating the distance information corresponding to the focus lens position.

[0009] According to an embodiment of the present disclosure, there is provided an image pickup device capable of attaching an accessory device including a focus lens for changing a focus lens position, the image pickup device including: a display unit including a display area for displaying distance information corresponding to the focus lens position; and a communication control unit configured to control communication with the accessory device via the communication unit, wherein the communication control unit receives: (A) information indicating the number of distance information displayed in association with the display area; (B) information indicating the number of distance information indicated by the number; (C) information indicating the position of each distance information relative to the display area; and (D) information indicating the distance information corresponding to the focus lens position.

[0010] According to an embodiment of the present disclosure, there is provided a control method for controlling an accessory device, wherein the accessory device is attachable to an imaging device including a display unit and includes a focus lens for changing a focus lens position, the display unit including a display area for displaying distance information corresponding to the focus lens position, the control method comprising: controlling communication with the imaging device via a communication unit, wherein, in the control of the communication, the following information is sent: (A) information indicating the number of distance information displayed in association with the display area; (B) information indicating the number of distance information indicated by the number; (C) information indicating the position of each distance information relative to the display area; and (D) information indicating the distance information corresponding to the focus lens position.

[0011] According to an embodiment of the present disclosure, a control method for controlling a camera apparatus is provided, wherein the camera apparatus is capable of attaching an accessory device including a focus lens for changing a focus lens position, the camera apparatus including a display unit, the display unit including a display area for displaying distance information corresponding to the focus lens position, the control method comprising: controlling communication with the accessory apparatus via a communication unit, wherein, in the control of the communication, the following information is received: (A) information indicating the number of distance information displayed in association with the display area; (B) information indicating the number of distance information indicated by the number; (C) information indicating the position of each distance information relative to the display area; and (D) information indicating the distance information corresponding to the focus lens position.

[0012] Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1A is a diagram illustrating a configuration of a camera system including an imaging apparatus and accessory devices according to an exemplary embodiment of the present disclosure.

[0014] Figure 1B are diagrams showing examples of the appearance of interchangeable lenses and various operating members.

[0015] Figure 2 is a schematic diagram showing a communication circuit between an imaging apparatus and an accessory device.

[0016] Figure 3A and Figure 3B Schematic diagram showing a communication waveform in the communication mode M1.

[0017] Figure 4 Schematic diagram showing a communication waveform in the communication mode M2.

[0018] Figure 5A 、 Figure 5B and Figure 5C Schematic diagram showing a communication waveform in the communication mode M3.

[0019] Figure 6 is a flowchart showing a flow of determining a communication format in an accessory device and an imaging apparatus.

[0020] Figure 7 3 is a flowchart showing the flow of data communication in the communication mode M2.

[0021] Figure 8 : is a schematic screen showing focus bar information displayed in the imaging apparatus.

[0022] Figure 9Schematic screen showing magnification information and depth of field information on the focal length bar information displayed in the imaging apparatus.

[0023] Figure 10 : is a flowchart showing a process regarding the start operation of the imaging apparatus and the accessory device.

[0024] Figure 11A is a flowchart illustrating stable operations of the imaging apparatus and accessory devices.

[0025] Figure 11B is a flowchart illustrating a process for updating the display of a camera display unit.

[0026] Figure 12 1 is a timing chart showing a communication status between the imaging apparatus and the accessory device in a stable state.

[0027] Figure 13 is a diagram illustrating a display example of a camera shake condition according to the second exemplary embodiment.

[0028] Figure 14 is a flowchart illustrating processing for displaying a camera shake condition according to the second exemplary embodiment.

[0029] Figure 15 is a flowchart illustrating lens communication control unit processing for displaying a camera shake condition according to the second exemplary embodiment.

[0030] Figure 16 : are diagrams illustrating a display example of zoom position information and various operating members of an interchangeable lens according to a third exemplary embodiment.

[0031] Figure 17 is a flowchart illustrating processing for displaying zoom position information according to the third exemplary embodiment.

[0032] Figure 18 is a flowchart illustrating lens communication control unit processing for displaying zoom position information according to the third exemplary embodiment.

[0033] Figure 19A and Figure 19B is a diagram illustrating the problem. DETAILED DESCRIPTION

[0034] A first exemplary embodiment will be described. A communication control method for controlling communication between an interchangeable lens, which is an accessory device according to the present disclosure, and a camera body, which is an imaging apparatus according to the present disclosure, will be described in detail below based on the accompanying drawings. First, definitions of terms used in this exemplary embodiment will be described.

[0035] "Communication format" refers to the overall communication rules between the camera body and the interchangeable lens. "Communication method" refers to the clock synchronization method and the asynchronous method. The clock synchronization method is communication method A, and the asynchronous method is communication method B. "Data format" refers to whether a waiting communication request signal (busy signal) can be added. The data format that allows the addition of a busy signal is "Format F1", and the data format that prohibits the addition of a busy signal is "Format F2".

[0036] "Communication mode" refers to a combination of a communication method and a data format. In this exemplary embodiment, the following three communication modes are described. "Communication mode M1" is a communication mode using communication method A and format F1. "Communication mode M2" is a communication mode using communication method B and format F1. Furthermore, "Communication mode M3" is a communication mode using communication method B and format F2.

[0037] The camera body performs communication by appropriately switching the above-described communication modes M1 , M2 , and M3 , so that an appropriate communication mode can be selected based on the combination of the camera body and the interchangeable lens or the imaging mode.

[0038] For example, if the camera body and interchangeable lens are compatible with communication mode M2 ​​and are transmitting and receiving large amounts of data, the communication mode of each camera body and interchangeable lens is switched to communication mode M3, and high-speed data communication is performed without adding a busy signal. If data processing in the interchangeable lens requires some time, the communication mode of each camera body and interchangeable lens is switched to communication mode M2, and data communication is performed with the addition of a busy signal. This enables data communication between the camera body and interchangeable lens without communication failure.

[0039] <Basic Configuration of Camera Body 200 and Interchangeable Lens 100>

[0040] Figure 1A The structure of an image pickup system (hereinafter referred to as a “camera system”) is shown, which includes a camera body 200 as an image pickup device according to a first exemplary embodiment of the present disclosure and an interchangeable lens 100 detachably attached to the camera body 200 as an accessory device according to the first exemplary embodiment of the present disclosure.

[0041] The camera body 200 and the interchangeable lens 100 transmit control commands and internal information via the communication control unit (communication control unit 209) included in the camera body 200 and the communication control unit (communication control unit 110) included in the interchangeable lens 100. Each communication control unit supports multiple communication formats. Based on the type of communication data or the purpose of communication, the communication control units synchronize with each other to switch to the same communication format, allowing the optimal communication format to be selected for each situation.

[0042] First, the specific configuration of the interchangeable lens 100 and the camera body 200 will be described. The interchangeable lens 100 and the camera body 200 are mechanically and electrically connected via a mounting portion (not shown) as a coupling mechanism and a communication terminal group included in the mounting portion. The interchangeable lens 100 receives power supplied from the camera body 200 via a power supply terminal (not shown) provided in the mounting portion of the interchangeable lens 100, and controls various actuators and the lens microcomputer 111. In addition, the interchangeable lens 100 and the camera body 200 communicate with each other via a communication terminal group 300 ( Figure 2 ) communicate with each other. The communication terminal group 300 includes a communication terminal group 300a (an example of a communication unit of an imaging device) provided in the mounting portion of the camera body 200, and a communication terminal group 300b (an example of a communication unit of an accessory device) provided in the mounting portion of the interchangeable lens 100. The communication terminal group 300a includes a communication terminal 301a (an example of a first communication unit of an imaging device), a communication terminal 302a (an example of a second communication unit of an imaging device), and a communication terminal 303a (an example of a third communication unit of an imaging device). The communication terminal group 300b includes a communication terminal 301b (an example of a first communication unit of an accessory device), a communication terminal 302b (an example of a second communication unit of an accessory device), and a communication terminal 303b (an example of a third communication unit of an accessory device).

[0043] The interchangeable lens 100 includes an imaging optical system. The imaging optical system includes, in order from the object OBJ side, a field lens 101, a variable magnification lens 102 for changing magnification, an aperture unit 114 for adjusting light intensity, an image blur correction lens 103, and a focus lens 104 for adjusting focus.

[0044] The variable power lens 102 and the focus lens 104 are held by lens holding frames 105 and 106, respectively. The lens holding frames 105 and 106 are connected in the optical axis direction (by the guide shaft) via a guide shaft (not shown). Figure 1A The optical lenses 102 and 104 are movably guided on a surface (indicated by dotted lines in FIG), and are driven in the optical axis direction by stepping motors 107 and 108, respectively. The stepping motors 107 and 108 move the variable magnification lens 102 and the focus lens 104, respectively, in synchronization with the driving pulses.

[0045] The image blur correction lens 103 moves in a direction orthogonal to the optical axis of the imaging optical system, thereby reducing image blur due to camera shake.

[0046] The lens microcomputer 111 is an accessory control unit that controls the operation of the components in the interchangeable lens 100. The lens microcomputer 111 receives control commands transmitted from the camera body 200 via the communication control unit 110, which serves as an accessory communication control unit, and receives a transmission request for lens data. Furthermore, the lens microcomputer 111 performs lens control corresponding to the control commands and transmits lens data corresponding to the transmission request to the camera body 200 via the communication control unit 110.

[0047] Furthermore, in response to a command regarding magnification change or focusing among the control commands, the lens microcomputer 111 outputs a drive signal to the zoom drive circuit 119 or the focus drive circuit 120, thereby driving the stepping motor 107 or 108, respectively. Thus, the lens microcomputer 111 performs zoom processing for controlling the magnification change operation by the variable magnification lens 102, or autofocus processing for controlling the focus adjustment operation by the focus lens 104. The focus position detection sensor 140 is a sensor for detecting the focal position when the focus lens 104 is being operated by autofocus processing or manual focus processing based on user operation. The lens microcomputer 111 obtains positional information about the focus lens 104 from the output of the focus position detection sensor 140.

[0048] The lens barrel includes the following reference Figure 1B The following describes an autofocus / manual focus (AF / MF) selection switch for switching between autofocus and manual focus, and a focus limit switch 141 for limiting the drive range of the focus lens 104. The focus limit switch 141 (also referred to as a "first operating member") is a switch that enables selection of, for example, "0.8 m to ∞" and "3 m to ∞." The focus limit switch 141 controls the movement of the focus lens 104 within a range limited by autofocus control. For example, to capture an image of a caged animal, the range of movement of the focus lens 104 is limited so that the closest side is not focused. This setting is effective in imaging scenes where focus control should be performed by limiting the focus to a predetermined distance range.

[0049] The aperture unit 114 includes aperture blades 114a and 114b. The states of the aperture blades 114a and 114b are detected by the Hall element 115 and input to the lens microcomputer 111 via the amplifier circuit 122 and the analog-to-digital (A / D) conversion circuit 123. Based on the input signal from the A / D conversion circuit 123, the lens microcomputer 111 outputs a drive signal to the aperture drive circuit 121, thereby driving the aperture actuator 113. This controls the light amount adjustment operation of the aperture unit 114.

[0050] Furthermore, based on the shake detected by the vibration sensor (not shown) of the vibration gyro provided in the interchangeable lens 100, the lens microcomputer 111 drives the image stabilization actuator 126 via the image stabilization drive circuit 125. Thus, image stabilization processing is performed for controlling the shift operation of the image blur correction lens 103. In addition, the shake sensor of the vibration gyro outputs signal information as camera shake information about the user, and the lens microcomputer 111 acquires current camera shake state information.

[0051] In the present exemplary embodiment, for example, focus position information obtained by the focus position detection sensor 140, camera shake status information obtained by the shake sensor of the vibration gyro, and zoom position information about the zoom lens are transmitted to the camera body 200. However, not only the focus position, camera shake status, and zoom position, but also any information held in the interchangeable lens 100 may be the subject of transmission.

[0052] The camera body 200 includes an image sensor 201 (e.g., a charge coupled device (CCD) sensor or a complementary metal oxide semiconductor (CMOS) sensor), an A / D conversion circuit 202, a signal processing circuit 203, a recording unit 204, a camera microcomputer 205, and a display unit 206 (an example of a display unit).

[0053] The image sensor 201 performs photoelectric conversion on a subject image formed by the imaging optical system in the interchangeable lens 100 and outputs an electrical signal (analog signal). The A / D conversion circuit 202 converts the analog signal from the image sensor 201 into a digital signal. The signal processing circuit 203 performs various types of image processing on the digital signal from the A / D conversion circuit 202 to generate a video signal.

[0054] The signal processing circuit 203 also generates information about the contrast state of the subject image based on the video signal, namely, focus information indicating the focus state of the imaging optical system and brightness information indicating the exposure state of the imaging optical system. The signal processing circuit 203 outputs the video signal to the display unit 206, and the display unit 206 displays the video signal as a live view image for confirming the composition and focus state.

[0055] In the live view image displayed on the display unit 206, various setting information about the camera body 200, such as the shutter speed and the aperture setting value, is displayed. In addition, in the present exemplary embodiment, the focus position information about the lens 100 transmitted from the lens microcomputer 111 via the communication control unit 110 is displayed in a superimposed manner on the live view screen. Figure 8 A specific display example is described.

[0056] In response to inputs from camera operating members such as an imaging instruction switch and various setting switches (not shown), the camera microcomputer 205, which serves as a camera control unit, controls the camera body 200. Furthermore, based on an operation of a zoom switch (not shown), the camera microcomputer 205 transmits a control command regarding a magnification changing operation of the variable-magnification lens 102 to the lens microcomputer 111 via a communication interface (I / F) circuit 208. Furthermore, the camera microcomputer 205 transmits a control command regarding a light amount adjustment operation of the aperture unit 114 based on brightness information or a focus adjustment operation of the focus lens 104 based on focus information to the lens microcomputer 111 via the communication I / F circuit 208.

[0057] Furthermore, in response to input from the camera operating member, a menu screen for changing various settings of the camera can be displayed on the display unit 206. It is possible to select whether to display various information about the lens 100 according to the present exemplary embodiment (e.g., object distance information) on the display unit 206, or to select information to be displayed (focal position, magnification information, or camera shake status).

[0058] Figure 1B An example of the appearance of the interchangeable lens 100 and various operating members is shown. A ring 150 is a zoom ring, and can drive the zoom position from the wide-angle area to the telephoto area based on a user operation or a communication instruction from the camera.

[0059] The ring 151 is a focus ring and enables a user to perform a manual focus operation.

[0060] The switch 152 is an operation member that enables switching between the automatic focus mode and the manual focus mode.

[0061] The switch 153 is an operation member that enables switching whether to enable or disable the image stabilization function.

[0062] Switch 154 corresponds to Figure 1A The focus limit switch 141 in FIG. In this example, it is possible to switch between three states, namely, "unlimited", "0.8 m to ∞", and "3.0 m to ∞".

[0063] <Basic Structure of Communication>

[0064] Next, refer to Figure 2, describes a communication circuit constructed between the camera body 200 and the interchangeable lens 100, and communication control performed between the camera body 200 and the interchangeable lens 100. The camera microcomputer 205 has a function for managing the communication format between the camera microcomputer 205 and the lens microcomputer 111, and a function for notifying the lens microcomputer 111 of a transmission request. The lens microcomputer 111 has a function for generating lens data and a function for transmitting lens data.

[0065] The camera microcomputer 205 and the lens microcomputer 111 communicate with each other via a communication terminal group 300 provided in the mount portion, and a communication I / F circuit 208 and a communication I / F circuit 112 provided in the camera microcomputer 205 and the lens microcomputer 111 , respectively.

[0066] In the present exemplary embodiment, the camera microcomputer 205 and the lens microcomputer 111 perform serial communication by communication methods A and B, which are three-wire communication methods using three channels (ie, first, second, and third communication channels).

[0067] Through the first communication channel, communication is performed via the communication terminals 301 a and 301 b .

[0068] The first communication channel is a notification channel, which is used as a clock channel in communication method A and is used as a transmission request channel in communication method B.

[0069] Through the second communication channel, communication is performed via the communication terminals 302a and 302b.

[0070] The second communication channel is used to transmit camera data from the camera microcomputer 205 to the lens microcomputer 111. The camera data transmitted as a signal from the camera microcomputer 205 through the second communication channel to the lens microcomputer 111 is referred to as a "camera data signal DCL."

[0071] Communication is performed via the third communication channel via the communication terminals 303a and 303b. The third communication channel is used to transmit lens data from the lens microcomputer 111 to the camera microcomputer 205. The lens data transmitted as a signal from the lens microcomputer 111 to the camera microcomputer 205 via the third communication channel is referred to as a "lens data signal DLC."

[0072] <Communication method A>

[0073] First, communication using communication method A will be described. In communication method A, the camera microcomputer 205, serving as a communication master, outputs a clock signal LCLK to the lens microcomputer 111, serving as a communication slave, via a clock channel. The camera data signal DCL includes a control command or a transmission request command from the camera microcomputer 205 to the lens microcomputer 111. On the other hand, the lens data signal DLC includes various data to be transmitted from the lens microcomputer 111 to the camera microcomputer 205 in synchronization with the clock signal LCLK. The camera microcomputer 205 and the lens microcomputer 111 can communicate with each other using a full-duplex communication method (full-duplex method), transmitting and receiving data simultaneously in synchronization with the common clock signal LCLK.

[0074] Figure 3A and Figure 3B 2 and 3 show waveforms of signals exchanged between the camera microcomputer 205 and the lens microcomputer 111. The rules of the exchange procedure are referred to as a "communication protocol."

[0075] Figure 3A The signal waveform of one frame, which is the minimum communication unit, is shown. First, the camera microcomputer 205 outputs a clock signal LCLK consisting of a set of eight periodic clock pulses, and also transmits a camera data signal DCL to the lens microcomputer 111 in synchronization with the clock signal LCLK. At the same time, the camera microcomputer 205 receives a lens data signal DLC output from the lens microcomputer 111 in synchronization with the clock signal LCLK.

[0076] Therefore, one byte (8 bits) of data is transmitted and received between the lens microcomputer 111 and the camera microcomputer 205 in synchronization with the clock signal LCLK as a set. The time period for transmitting and receiving one byte of data is called a "data frame". After transmitting and receiving one byte of data, the lens microcomputer 111 transmits a signal (hereinafter referred to as a "busy signal") for notifying the camera microcomputer 205 of a waiting communication request BUSY, thereby inserting a waiting communication time period. The waiting communication time period is called a "busy frame". When receiving a busy frame, the camera microcomputer 205 is in a waiting communication state. Then, a communication unit consisting of a set of a data frame time period and a busy frame time period is one frame. There is also a case where a busy frame is not added depending on the communication situation. However, in this case, one frame consists of only a data frame time period.

[0077] Figure 3B Signal waveforms are shown when the camera microcomputer 205 transmits a request command CMD1 to the lens microcomputer 111 and receives two bytes of lens data DT1 ( DT1 a and DT1 b ) corresponding to the request command CMD1 from the lens microcomputer 111 . Figure 3BAn example is shown in which data communication is performed according to “communication CMD1 ”.

[0078] The types and byte counts of lens data DT corresponding to various types of commands CMD are predetermined between the camera microcomputer 205 and the lens microcomputer 111. When the camera microcomputer 205, acting as the communication master, transmits a specific command CMD to the lens microcomputer 111, the lens microcomputer 111 transmits the required clock frequency to the camera microcomputer 205 based on information regarding the byte count of the lens data corresponding to the command CMD. Furthermore, the lens microcomputer 111's processing of command CMD1 includes superimposing a busy signal on the clock signal LCLK for each frame, and inserting this busy frame between data frames.

[0079] In communication CMD1, the camera microcomputer 205 transmits a clock signal LCLK to the lens microcomputer 111, and transmits a request command CMD1 requesting transmission of lens data DT1 as a camera data signal DCL to the lens microcomputer 111. The lens data signal DLC of this frame is regarded as invalid data.

[0080] Next, the camera microcomputer 205 outputs a clock signal LCLK in eight cycles via the clock channel, and then switches the clock channel on the camera microcomputer 205 side (camera body 200 side) from output to input. Once the clock channel switching on the camera microcomputer 205 side is complete, the lens microcomputer 111 switches the clock channel on the lens microcomputer 111 side (interchangeable lens 100 side) from input to output. Then, to notify the camera microcomputer 205 that it is waiting for the communication request BUSY, the lens microcomputer 111 sets the voltage level of the clock channel to low. Consequently, the lens microcomputer 111 superimposes a busy signal on the clock channel. While the camera microcomputer 205 is notified of the waiting for the communication request BUSY, the camera microcomputer 205 maintains the clock channel in the input setting and stops communication with the lens microcomputer 111.

[0081] During the period in which the lens microcomputer 111 notifies the camera microcomputer 205 of the waiting communication request BUSY, the lens microcomputer 111 generates lens data DT1 corresponding to the transmission request command CMD1. Then, when preparations for transmitting the lens data DT1 as the lens data signal DLC of the next frame are completed, the lens microcomputer 111 switches the signal level of the clock channel on the lens microcomputer 111 side to High and cancels the waiting communication request BUSY.

[0082] If the cancellation of the waiting communication request BUSY is recognized, the camera microcomputer 205 transmits the clock signal LCLK for one frame to the lens microcomputer 111, thereby receiving the lens data DT1a from the lens microcomputer 111. In the next frame, the camera microcomputer 205 outputs the clock signal LCLK for eight cycles again, and the camera microcomputer 205 and the lens microcomputer 111 repeat operations similar to those described above, whereby the camera microcomputer 205 receives the lens data DT1b from the lens microcomputer 111.

[0083] <Communication Method B>

[0084] Next, communication by the communication method B is described. At the same time, a communication mode M2 ​​for performing communication in the format F1 using the communication method B is also described. Figure 4 1 and 2 show waveforms of communication signals exchanged in the communication mode M2 ​​between the camera microcomputer 205 and the lens microcomputer 111. As described above, in the format F1, a busy frame is selectively added to the lens data signal DLC.

[0085] In communication method B, the transmission request channel is used by the camera microcomputer 205, serving as the communication master, to notify the lens microcomputer 111, serving as the communication slave, of a transmission request to transmit lens data. This notification is given by switching the level (voltage level) of the signal passing through the transmission request channel between high (a first level) and low (a second level). In the following description, the signal supplied to the transmission request channel in communication method B is referred to as a "transmission request signal RTS."

[0086] Similar to the communication method A, the first data communication channel (corresponding to the third communication channel) is used to transmit the lens data signal DLC including various data from the lens microcomputer 111 to the camera microcomputer 205. Similar to the communication method A, the second data communication channel (corresponding to the second communication channel) is also used to transmit the camera data signal DCL including a control command or a transmission request command from the camera microcomputer 205 to the lens microcomputer 111.

[0087] In communication method B, unlike communication method A, the camera microcomputer 205 and the lens microcomputer 111 do not transmit and receive data in synchronization with a common clock signal. Instead, they set the communication speed in advance and transmit and receive data to and from each other at a communication bit rate based on the setting. The communication bit rate indicates the amount of data that can be transmitted per second, and the unit of the communication bit rate is expressed in bits per second (bps).

[0088] In the present exemplary embodiment, also in the communication method B, similarly to the communication method A, the camera microcomputer 205 and the lens microcomputer 111 communicate with each other by the full-duplex communication method (full-duplex method) to mutually transmit and receive data.

[0089] Figure 4 The signal waveform of one frame, which is the minimum communication unit, is shown. The camera data signal DCL and the lens data signal DLC partially differ in the breakdown of the data format of one frame.

[0090] First, the data format of the lens data signal DLC is described. A frame of the lens data signal DLC includes a data frame in the first half of the lens data signal DLC and a busy frame following the data frame. When no data is being transmitted, the signal level of the lens data signal DLC remains high.

[0091] To notify the camera microcomputer 205 that it has started transmitting the lens data signal DLC for one frame, the lens microcomputer 111 sets the voltage level of the lens data signal DLC to low for one bit period. This one bit period is called the "start bit ST," and the data frame begins with the start bit ST. Next, the lens microcomputer 111 transmits one byte of lens data in an eight-bit period, from the second bit to the ninth bit after the start bit ST.

[0092] In the most significant bit (MSB) first format, the data bit array begins with the most significant data D7, continues with data D6 and D5, and ends with the least significant data D0. The lens microcomputer 111 then adds one bit of parity information (PA) to the tenth bit and sets the voltage level of the lens data signal DLC to high during the time period of the stop bit SP, which indicates the end of a frame. This completes the data frame period starting from the start bit ST. The parity information need not be a single bit. Alternatively, multiple bits of parity information may be added. Furthermore, parity information is not essential. Alternatively, a format without parity information may be employed.

[0093] Next, if Figure 4 As shown by "DLC (BUSY: Yes)" in the communication method, the lens microcomputer 111 adds a busy frame after the stop bit SP. Similar to communication method A, the busy frame indicates a period of time during which the lens microcomputer 111 notifies the camera microcomputer 205 of the waiting communication request BUSY. The lens microcomputer 111 maintains the signal level of the lens data signal DLC at a low level until the waiting communication request BUSY is canceled.

[0094] On the other hand, there is a case where the lens microcomputer 111 does not need to notify the camera microcomputer 205 of the waiting communication request BUSY. Figure 4As shown in "DLC (BUSY: None)" in the figure, a data format is also provided in which a busy frame (hereinafter also referred to as "busy notification") is not added to form one frame. In other words, the data format of the lens data signal DLC can be selected based on the processing status of the lens microcomputer 111 to select a lens data signal DLC with a busy notification added or a lens data signal DLC without a busy notification added.

[0095] A recognition method for recognizing the presence or absence of a busy notification by the camera microcomputer 205 is described. Figure 4 The signal waveform shown in "DLC (BUSY: None)" and Figure 4 The signal waveform shown in "DLC (BUSY: Yes)" in FIG. 1 includes bit positions B1 and B2. The camera microcomputer 205 selects either bit position B1 or B2 as a busy identification position P for identifying the presence or absence of a busy notification. As described above, in this exemplary embodiment, a data format is adopted in which the busy identification position P is selected from bit positions B1 and B2. This solves the problem that the processing time after a data frame of the lens data signal DLC is transmitted until the busy notification is finally determined (the lens data signal DLC is low) varies depending on the processing performance of the lens microcomputer 111.

[0096] Before communication by the communication method B is performed, which of the bit positions B1 and B2 is to be selected as the busy recognition position P is determined by communication between the camera microcomputer 205 and the lens microcomputer 111. The busy recognition position P may not need to be fixed to either of the bit positions B1 and B2 and may be changed according to the processing capabilities of the camera microcomputer 205 and the lens microcomputer 111. The busy recognition position P is not limited to the bit positions B1 and B2 and may be set to a predetermined position after the stop bit SP.

[0097] The reason for adopting the following data format is described, in which the communication method A

[0098] The busy frame added to the clock signal LCLK in communication method B is added to the lens data signal DLC.

[0099] In communication method A, the clock signal LCLK output from the camera microcomputer 205, which serves as the communication master, and the busy signal output from the lens microcomputer 111, which serves as the communication slave, need to be exchanged via the same clock channel. Therefore, conflicts between the outputs of the camera microcomputer 205 and the lens microcomputer 111 are prevented by time division. That is, by appropriately allocating the time periods during which the camera microcomputer 205 and the lens microcomputer 111 are allowed to provide outputs via the clock channel, conflicts between the outputs can be prevented.

[0100] However, in the time-division method, it is necessary to reliably prevent a conflict between the output of the camera microcomputer 205 and the output of the lens microcomputer 111. Therefore, a specific output-disabled period, which disables both the microcomputers 205 and 111 from providing outputs, is inserted between the time when the camera microcomputer 205 completes output of the eight-pulse clock signal LCLK and the time when the lens microcomputer 111 is allowed to output a busy signal. This output-disabled period is a communication-invalidated period during which the camera microcomputer 205 and the lens microcomputer 111 cannot communicate with each other. This reduces the effective communication speed.

[0101] To solve such a problem, in the communication method B, a data format is adopted in which a busy frame from the lens microcomputer 111 is added to the lens data signal DLC in the first data communication channel which is a dedicated output channel of the lens microcomputer 111 .

[0102] Next, the data format of the camera data signal DCL is described. The data frame specification of one frame of the camera data signal DCL is similar to that of the lens data signal DLC. However, unlike the lens data signal DLC, adding a busy frame to the camera data signal DCL is prohibited.

[0103] Next, a description is given of a communication procedure between the camera microcomputer 205 and the lens microcomputer 111 in communication method B. First, if an event for starting communication with the lens microcomputer 111 occurs, the camera microcomputer 205 sets the voltage level of the transmission request signal RTS to low (hereinafter, “asserts the transmission request signal RTS”), thereby notifying the lens microcomputer 111 of the communication request.

[0104] If a communication request is detected due to the voltage level of the transmission request signal RTS going low, the lens microcomputer 111 performs processing to generate a lens data signal DLC to be transmitted to the camera microcomputer 205. Then, if preparations for transmitting the lens data signal DLC are complete, the lens microcomputer 111 starts transmitting the lens data signal DLC for one frame via the first data communication channel. At this time, the lens microcomputer 111 starts transmitting the lens data signal DLC within a set time set between the camera microcomputer 205 and the lens microcomputer 111, starting from the time the voltage level of the communication request signal RTS goes low.

[0105] That is, in communication method B, the lens data to be transmitted may only need to be finalized between the time the voltage level of the communication request signal RTS goes low and the time the lens data signal DLC starts to be transmitted. Unlike communication method A, there are no strict restrictions, such as requiring the lens data to be finalized before or at the time the first clock pulse is input. Therefore, the timing for starting to transmit the lens data signal DLC can be set flexibly.

[0106] Next, upon detecting the start bit ST added to the beginning of the data frame of the lens data signal DLC received from the lens microcomputer 111, the camera microcomputer 205 changes the voltage level of the transmission request signal RTS back to high (hereinafter referred to as "negation of the transmission request signal RTS"). Thus, the camera microcomputer 205 cancels the transmission request and also begins transmitting the camera data signal DCL via the second communication channel. It does not matter which of the negation of the transmission request signal RTS and the start of transmission of the camera data signal DCL is performed first. These processes only need to be performed upon or before the completion of reception of the data frame of the lens data signal DLC.

[0107] If the lens microcomputer 111, which has already transmitted a data frame of the lens data signal DLC, needs to notify the camera microcomputer 205 that it is waiting for a communication request BUSY, the lens microcomputer 111 adds a busy frame to the lens data signal DLC. The camera microcomputer 205 monitors the presence or absence of notification of the waiting communication request BUSY. If the camera microcomputer 205 is notified of the waiting communication request BUSY, the camera microcomputer 205 is prohibited from asserting the transmission request signal RTS for the next transmission request.

[0108] The lens microcomputer 111 uses the communication waiting request BUSY to execute necessary processing during the period in which the lens microcomputer 111 holds the camera microcomputer 205 on standby for communication. After completing preparations for the next communication, the lens microcomputer 111 cancels the communication waiting request BUSY. Under the condition that the communication waiting request BUSY is canceled and the transmission of the data frame of the camera data signal DCL is completed, the camera microcomputer 205 is allowed to assert the transmission request signal RTS for the next transmission request.

[0109] As described above, in the present exemplary embodiment, in accordance with the fact that the transmission request signal RTS is asserted using the communication start event in the camera microcomputer 205 as a trigger, the lens microcomputer 111 starts transmitting the data frame of the lens data signal DLC to the camera microcomputer 205. Then, in accordance with detection of the start bit ST of the lens data signal DLC, the camera microcomputer 205 starts transmitting the data frame of the camera data signal DCL to the lens microcomputer 111.

[0110] At this time, the lens microcomputer 111 adds a busy frame after the data frame of the lens data signal DLC, if necessary, to wait for the communication request BUSY. The lens microcomputer 111 then cancels the waiting period for the communication request BUSY, completing the communication process for transmitting one frame. Through this communication process, the camera microcomputer 205 and the lens microcomputer 111 exchange one byte of communication data.

[0111] Next, a communication mode M3 for performing communication in the format F2 using the communication method B is described. Figure 5A Waveforms of communication signals exchanged between the camera microcomputer 205 and the lens microcomputer 111 in the communication mode M3 are shown. Figure 5A 1 and 2 show waveforms of communication signals when three frames of data are continuously transmitted. As described above, in the format F2, it is prohibited to add the waiting communication request BUSY to the lens data signal DLC.

[0112] In the data format of the lens data signal DLC in the communication mode M3, one frame consists of only a data frame, and there is no busy frame. Therefore, in the communication mode M3, the lens microcomputer 111 cannot notify the camera microcomputer 205 of waiting for the communication request BUSY.

[0113] This format F2 is used for performing continuous communication in which the interval between frames is shortened when a relatively large amount of data is transferred between the camera microcomputer 205 and the lens microcomputer 111. That is, the format F2 enables high-speed communication of a large amount of data.

[0114] Next, communication control processing between the camera microcomputer 205 and the lens microcomputer 111 , which is a feature of the present exemplary embodiment, will be described. Figure 5B The waveforms of communication signals are shown when the camera microcomputer 205 and the lens microcomputer 111 continuously transmit and receive the camera data signal DCL and the lens data signal DLC for n frames. When an event occurs to initiate communication with the lens microcomputer 111, the camera microcomputer 205 asserts the transmission request signal RTS. Unlike format F1, in format F2, the camera microcomputer 205 does not need to negate the transmission request signal RTS for each frame. Therefore, while data can be continuously transmitted and received, the camera microcomputer 205 maintains the assertion of the transmission request signal RTS.

[0115] If a communication request is detected due to assertion of the transmission request signal RTS, the lens microcomputer 111 performs processing for generating a lens data signal DLC to be transmitted to the camera microcomputer 205. Then, if preparation for transmitting the lens data signal DLC is completed, the lens microcomputer 111 starts transmitting the lens data signal DLC of the first frame through the first data communication channel (DL1).

[0116] The lens microcomputer 111, having already transmitted the first frame of the lens data signal DLC, reasserts the transmission request signal RTS. At this point, if the transmission request signal RTS is asserted, the lens microcomputer 111 transmits the lens data signal DLC (DL2) for the next second frame to the camera microcomputer 205 after completing transmission of the first frame. While the transmission request signal RTS is asserted, the lens data signals DLC (DL1 to DLn) from the lens microcomputer 111 are continuously transmitted to the camera microcomputer 205. Subsequently, upon completion of transmission of the lens data signal DLC for a predetermined number of n frames, transmission of the lens data signal DLC is stopped.

[0117] Upon detecting the start bit ST of each frame of the lens data signal DLC from the lens microcomputer 111 , the camera microcomputer 205 starts transmitting the camera data signal DCL ( DC1 to DCn) of n frames through the second communication channel.

[0118] Figure 5C Shown in Figure 5B The waveform of the communication signal shown in FIG. 1 is obtained when the camera microcomputer 205 or the lens microcomputer 111 issues an instruction to temporarily wait for communication during the communication period of continuous data transmission and reception. Also in this case, the camera microcomputer 205 asserts the communication request signal RTS, causing the lens microcomputer 111 to start transmitting the lens data signal DLC. Then, upon detecting the start bit ST of the lens data signal DLC, the camera microcomputer 205 starts transmitting the camera data signal DCL.

[0119] The waiting communication period T2w1 indicates a period during which the camera microcomputer 205 gives an instruction to wait for communication. The camera microcomputer 205 temporarily negates the transmission request signal RTS, thereby notifying the lens microcomputer 111 of the instruction. If negation of the transmission request signal RTS is detected, the lens microcomputer 111 completes the frame of the lens data signal DLC that was being transmitted when negation was detected ( Figure 5C Then, the lens microcomputer 111 suspends transmission.

[0120] In response to the suspension of transmission of the lens data signal DLC, the camera microcomputer 205 also transmits a frame (DC6) corresponding to the pause frame in the camera data signal DCL, and then suspends transmission of the camera data signal DCL. Through this communication control, even if a communication standby instruction is given during communication in which data is continuously transmitted and received, the lens data signal DLC and the camera data signal DCL can be managed so that the number of transmission frames of the lens data signal DLC and the camera data signal DCL is the same.

[0121] If there are no pending communication request events, the camera microcomputer 205 asserts the transmission request signal RTS again, thereby instructing the lens microcomputer 111 to resume communication. In response to the communication resumption instruction, the lens microcomputer 111 resumes transmission of the lens data signal DLC from the frame following the pause frame (DL7: hereinafter referred to as the "resumption frame"). Then, upon detecting the start bit ST of the resumption frame, the camera microcomputer 205 resumes transmission of the frame (DC7) corresponding to the resumption frame in the camera data signal DLC.

[0122] On the other hand, the waiting communication time period T2w2 represents a time period during which the lens microcomputer 111 gives an instruction to wait for communication. Figure 5C In the embodiment, after the end of the waiting communication time period T2w1, neither the camera microcomputer 205 nor the lens microcomputer 111 gives an instruction to wait for communication, and the camera microcomputer 205 and the lens microcomputer 111 continuously transmit and receive data to and from each other in the order of restored frames DL7 and DC7, frames DL8 and DC8 after the restored frames DL7 and DC7, and frames DL9 and DC9.

[0123] Then, when transmission of the frame DL9 from the lens microcomputer 111 (reception of the frame DC9 from the camera microcomputer 205 ) is completed, a wait communication request event occurs, whereby the lens microcomputer 111 notifies the camera microcomputer 205 of a wait communication instruction.

[0124] When the transmission request signal RTS is in the asserted state, the lens microcomputer 111 does not transmit the lens data signal DLC, thereby notifying the camera microcomputer 205 that communication is to be suspended.

[0125] The camera microcomputer 205 continuously monitors the start bit ST of each frame of the lens data signal DLC. A rule is made such that if the camera microcomputer 205 does not detect the start bit ST, the camera microcomputer 205 suspends transmission of the next frame of the camera data signal DLC. Even if the transmission request signal RTS is asserted, if the camera microcomputer 205 does not receive the lens data signal DLC ( Figure 5CWhen the lens microcomputer 111 gives an instruction, the camera microcomputer 205 keeps the transmission request signal RTS in the asserted state during the waiting communication period T2w2.

[0126] Then, there is no waiting communication request event in the lens microcomputer 111, and the lens microcomputer 111 resumes transmission of the resumption frame DL10 in the lens data signal DLC. Upon detecting the start bit ST of the resumption frame DL10, the camera microcomputer 205 resumes transmission of the corresponding frame DC10 in the camera data signal DCL.

[0127] Next, we will refer to Figure 6 A description is given of a procedure for determining a communication format between the camera microcomputer 205 and the lens microcomputer 111. Based on a communication control program which is a computer program, the camera microcomputer 205 and the lens microcomputer 111 perform communication. Figure 6 and Figure 7 The communication control is shown in the flowchart.

[0128] First, if the interchangeable lens 100 is attached to the camera body 200, in steps S100 and S200, the camera microcomputer 205 and the lens microcomputer 111 set an initial communication format that ensures communication is established. The initial communication format may be a combination of the communication method and data format discussed in this exemplary embodiment, or a communication format other than the combination discussed in this exemplary embodiment. When the asynchronous communication format is selected as the initial communication format, it is desirable to set the busy identification position P so that communication can be established regardless of the camera and interchangeable lens combination.

[0129] Next, in step S101, the camera microcomputer 205 transmits camera identification information indicating a communication format compatible with the camera body 200 to the lens microcomputer 111. Furthermore, in step S202, the lens microcomputer 111 transmits lens identification information indicating a communication format compatible with the interchangeable lens 100 to the camera microcomputer 205.

[0130] At this time, the "identification information" includes information indicating which of the clock synchronous communication method and the asynchronous communication method the camera body 200 and the interchangeable lens 100 are compatible with, and information indicating the range of communication bit rates compatible with each of the camera body 200 and the interchangeable lens 100. The identification information also includes information indicating a busy identification position P.

[0131] In step S102, the camera microcomputer 205 receives the lens identification information. In step S201, the lens microcomputer 111 receives the camera identification information. Figure 6 In the flowchart, the lens identification information is sent after the camera identification information is sent. Optionally, the camera identification information and the lens identification information can be sent at the same time. Optionally, the camera identification information can be sent after the lens identification information is sent.

[0132] Next, in steps S103 and S203, the communication format used for subsequent communication is set. Specifically, the camera microcomputer 205 and the lens microcomputer 111 determine the fastest communication bit rate among the communication bit rates compatible with the camera microcomputer 205 and the lens microcomputer 111 as the communication bit rate. Furthermore, the camera microcomputer 205 and the lens microcomputer 111 set the busy recognition position P, among the busy recognition positions P compatible with the camera microcomputer 205 and the lens microcomputer 111, that is closest to the stop bit SP as the busy recognition position P.

[0133] By the above-described communication control, the communication mode of the camera microcomputer 205 and the lens microcomputer 111 shifts to the state of the communication mode M2.

[0134] <Data Communication Flow in Asynchronous Communication Method>

[0135] Next, we will refer to Figure 7 Describes the data communication flow in the asynchronous communication method. Figure 7 , a description of the communication flow in a data format that allows adding a busy signal is given.

[0136] The camera microcomputer 205 monitors whether a communication event occurs for starting communication with the lens microcomputer 111. If a communication event occurs in step S110 (YES in step S110), the process proceeds to step S111. In step S111, as described above, the camera microcomputer 205 asserts the communication request signal RTS, thereby issuing a communication request to the lens microcomputer 111.

[0137] The lens microcomputer 111 monitors whether the communication request signal RTS is asserted. If the lens microcomputer 111 recognizes in step S210 that the communication request signal RTS is asserted (YES in step S210), the process proceeds to step S211. In step S211, the lens microcomputer 111 transmits the lens data signal DLC to the camera microcomputer 205 via the first data communication channel.

[0138] If the camera microcomputer 205 receives the lens data signal DLC from the lens microcomputer 111 (YES in step S112), the process proceeds to step S113. In step S113, the camera microcomputer 205 negates the communication request signal RTS. The process then proceeds to step S114. In step S114, the camera microcomputer 205 transmits the camera data signal DLC to the lens microcomputer 111 via the second data communication channel.

[0139] If the lens microcomputer 111 detects the start of reception of the camera data signal DCL in step S212 (YES in step S212), the process proceeds to step S213. In step S213, the lens microcomputer 111 performs processing for receiving the camera data signal DCL. In step S214, in parallel with the processing in step S213, the lens microcomputer 111 determines whether it is necessary for the lens microcomputer 111 to notify the camera microcomputer 205 of a waiting communication request BUSY. If it is not necessary for the lens microcomputer 111 to notify the camera microcomputer 205 of a waiting communication request BUSY (NO in step S214), the process proceeds to step S218. In step S218, the lens microcomputer 111 waits until reception of the camera data signal DCL is complete.

[0140] On the other hand, if the lens microcomputer 111 needs to notify the camera microcomputer 205 of the pending communication request BUSY (YES in step S214), the process proceeds to step S215. In step S215, the lens microcomputer 111 adds a busy frame to the lens data signal DLC. While notifying the camera microcomputer 205 of the pending communication request BUSY, the lens microcomputer 111 performs necessary processing. After completing preparations for the next communication (YES in step S216), the lens microcomputer 111 cancels the pending communication request BUSY in step S217. After the lens microcomputer 111 cancels the pending communication request BUSY, the process proceeds to step S218. In step S218, the lens microcomputer 111 waits until the camera data signal DCL is received. If the camera data signal DCL is received (YES in step S218), the process returns to step S210. In step S210, the lens microcomputer 111 continues to monitor whether the communication request signal RTS is asserted.

[0141] If the camera microcomputer 205 receives a notification of waiting for the communication request BUSY in step S115 (YES in step S115), it waits until the waiting for the communication request BUSY is canceled. If the waiting for the communication request BUSY is canceled (YES in step S116), the process proceeds to step S117. In step S117, the camera microcomputer 205 determines whether the transmission of the camera data signal DCL is complete. If the notification of waiting for the communication request BUSY is not received in step S115 (NO in step S115), the process proceeds to step S117. In step S117, the camera microcomputer 205 determines whether the transmission of the camera data signal DCL is complete. If it is determined in step S117 that the transmission of the camera data signal DCL is complete (YES in step S117), the process returns to step S110. In step S110, the camera microcomputer 205 continues to monitor whether a communication event occurs.

[0142] As described above, the present exemplary embodiment relates to communication control in asynchronous communication (communication method B) consisting of three channels. The lens microcomputer 111 transmits a communication waiting request BUSY to the camera microcomputer 205 via the first data communication channel, which is a dedicated output channel of the lens microcomputer 111. On the other hand, a transmission request signal RTS from the lens microcomputer 205 is transmitted from the camera microcomputer 205 to the lens microcomputer 111 via the notification channel, which is a dedicated output channel of the camera microcomputer 205.

[0143] As described above, the waiting communication request BUSY from the lens microcomputer 111 is transmitted and received via the dedicated output channel of the lens microcomputer 111, and the transmission request signal RTS from the camera microcomputer 205 is transmitted and received via the dedicated output channel of the camera microcomputer 205. This can shorten the communication ineffective period between the camera microcomputer 205 and the lens microcomputer 111. As a result, the effective communication speed can be increased.

[0144] Regarding the start timing of communication, data transmission is first started from the lens microcomputer 111 to the camera microcomputer 205. The camera microcomputer 205 starts transmitting data in response to detection of the start bit ST of the data frame transmitted from the lens microcomputer 111. By setting the start timing of communication in this manner, it is possible to flexibly set the timing at which the lens microcomputer 111, which has received the transmission request signal RTS, starts transmitting data to the camera microcomputer 205.

[0145] For example, the start timing of data transmission can be changed according to the information processing capability of the lens microcomputer 111. This can increase the communication speed between the camera body 200 and the interchangeable lens 100 without causing communication interruption.

[0146] <Problem Assumed in This Exemplary Embodiment>

[0147] A problem assumed in the present exemplary embodiment is described.

[0148] If an attempt is made to display an index of distance information without considering specification differences between interchangeable lenses such as wide-angle lenses and telephoto lenses, or specification differences between cameras (such as specification differences in the number of pixels of the display members of the cameras), problems arise in the following cases.

[0149] Figure 19A : shows a representative index position on the distance bar sent from the lens microcomputer 111 to the camera microcomputer 205. More specifically, Figure 19A The display position of each indicator position is specified by the number of pixels. Positions 2001 to 2007 indicate the starting position, where representative indicators "0.45m", "0.6m", "0.8m", "1m", "1.5m", "3m", and "5m" are displayed.

[0150] Position 2008 indicates the display origin position, and the display start position "0.45 m" is represented by the number of pixels counted from the display origin 2008, for example, "30 pixels." Similarly, the display start position "0.6 m" is represented by the number of pixels counted from the display origin 2008, for example, "150 pixels."

[0151] In this method, in order to effectively utilize the entire length of the distance bar, the lens microcomputer 111 of the interchangeable lens 100 needs to grasp in advance the number of pixels of the entire length of the display member of the camera to which the interchangeable lens 100 is attachable.

[0152] Furthermore, if similar information is exchanged when the number of effective pixels of the display member of the camera increases, as shown in FIG. Figure 19B As shown, the indicator position is displayed as Figure 19A In this case, there is a possibility that it is difficult to recognize the boundary between “3m” and “5m” as shown at the position 2011, and “3m” and “5m” are mistakenly recognized as “35m”.

[0153] To solve such a problem, a technology can be adopted in which specifications such as the number of effective pixels of the camera's display component are sent to the lens, and the lens sends object distance information and representative index positions to the camera based on the number of effective pixels of the camera's display component. However, since the number of effective pixels of a camera to be released later than the lens product cannot be known in advance, it is difficult to ensure compatibility. In addition, even if various items (such as object distance information, representative index values, macro magnification information, and focus range information) are displayed on the camera's display unit, it is necessary to prevent these items from affecting the drive control of focusing, aperture, and image stabilization. In addition, if a delay also occurs in the communication of information for display, this causes a delay in the display and thus reduces usability. Therefore, it is necessary to reduce the amount of communication regarding the communication of information for display.

[0154] In the present exemplary embodiment, not only does the lens microcomputer 111 transmit appropriate information based on the specifications of the lens 100 to the camera microcomputer 205, but the lens microcomputer 111 also transmits a normalized value when necessary to the camera microcomputer 205. Therefore, information corresponding to the interchangeable lens 100 can be appropriately displayed on the camera display unit 206.

[0155] <Example of the display screen for object distance information on the distance bar>

[0156] Next, we will refer to Figure 8 A description is given of an example of a display screen of distance bar information on which object distance information about the lens 100 according to the present exemplary embodiment is displayed at the camera display unit 206 .

[0157] A live view display screen 801 is displayed at the camera display unit 206 .

[0158] Icon 802 indicates the image capture mode information of the camera set in the menu of the camera. In this example, the image capture mode information indicates the shutter speed priority mode.

[0159] Information display 803 relates to image capturing (such as shutter speed, aperture value, exposure setting value, and International Organization for Standardization (ISO) sensitivity) as various setting information in current image capturing conditions.

[0160] The subject 804 represents the subject when the image is captured. In a state where the subject 804 is focused, position information on the focus lens 104 is transmitted from the lens microcomputer 111 to the camera microcomputer 205 as object distance information.

[0161] The distance bar 805 indicates a distance range in which an image can be captured from the closest focus side to the infinite focus side, which is a specification of the interchangeable lens 100 .

[0162] The value 806 is a representative index value of distance information for facilitating visual confirmation of the current object distance information, and is expressed as, for example, "0.45 m," "1.5 m," and "5 m." Such an index regarding the object distance is also referred to as a "first index." The display position of these representative index values, the number of representative index values ​​to be displayed, and the display interval between representative index values ​​are changed based on the specifications of the interchangeable lens 100 (wide-angle lens or telephoto lens), thereby achieving optimal display quality.

[0163] The focus infinity position icon 807 indicates that the focal length is infinity. The focus infinity position icon 807 is also referred to as a "second indicator." Typically, the interchangeable lens 100 is designed so that the focus lens position for telephoto focus is not at the infinity end of the physical range of motion of the focus lens 104, and a margin is provided beyond the infinity end. The amount of margin varies depending on the optical design of the interchangeable lens 100. In this exemplary embodiment, the margin is referred to as a "super-infinity range." The area from the display position of the infinity icon 807 to the right end of the bar 805 represents the super-infinity range. As described above, the amount of super-infinity range varies depending on the model of the interchangeable lens 100. Therefore, the display position of the infinity icon 807 changes based on the model of the interchangeable lens 100 to be attached.

[0164] Icon 808 indicates the unit system of the currently displayed object distance information, for example, "m" represents meters and "ft" represents feet.

[0165] The indicator 809 indicates the current position information of the focus lens 104, that is, the object distance information when the focus lens 104 is in focus. Figure 8 , the current position of the focus lens 104 is near the index position of "1.5 m". Therefore, it can be visually confirmed that the focal length is approximately 1.5 m.

[0166] The focus limit area 810 indicates the area where focus drive is restricted when the focus limit switch 141 included in the interchangeable lens 100 is enabled. The focus limit area 810 shows an example in which the focus limit switch 141 is switched to "0.8 m to ∞." This indicates that the area "closest to 0.8 m" is not used for autofocus. Typically, some interchangeable lenses 100 include a focus limiter SW that switches the focal length range for autofocus. However, the area to be restricted varies depending on the model of the interchangeable lens 100. Therefore, the focus limit area 810 can be switched by acquiring it from the lens microcomputer 111 based on the model of the lens 100 to be attached and the switch status.

[0167] Icons 811 and 812 indicate the driving direction of the focus lens 104. When the focus is driven in the infinity direction, the icon 811 is displayed, and the icon 812 is hidden. When the focus is driven in the closest direction, the icon 811 is hidden, and the icon 812 is displayed.

[0168] Depending on the interchangeable lens, the user can store a specific focus lens position in advance in the lens microcomputer included in the interchangeable lens. For example, the user can operate the focus ring to a specific position of the focus ring corresponding to the desired focus lens position and store information corresponding to the focus lens position. Then, for example, by operating an operating member provided in the interchangeable lens, the user can regenerate the focus lens to the stored focus lens position. The display screen 801 can indicate that regenerative drive is in progress. For example, icons 811 or 812 can be displayed to indicate that the focus lens 104 is being driven and to let the user know that regenerative drive is in progress. In addition, for example, an icon different from icons 811 and 812 can be displayed (not shown). In this case, the information to be stored in the lens microcomputer only needs to be information corresponding to the pre-set focus lens position, and, for example, the position of the focus ring can be stored.

[0169] Arrow 813 indicates the position of the representative indicator position "0.6m" on the distance bar. Position information is acquired from the lens microcomputer 111 via communication, and when the total length of the distance bar is 100, the position information indicates the placement position starting at the left end (i.e., the closest end) of the distance bar. For example, to place the representative indicator position "0.6m" 10% of the total length of the distance bar from the left end, information indicating that the indicator "0.6m" is placed at the standardized position "10" is acquired from the lens microcomputer 111. Although shown in the figure for ease of description, arrow 813 is not displayed on the actual live view screen 801. Similarly, arrows 814 and 815 are not displayed on the live view screen 801.

[0170] Similar to the arrow 813 , the arrow 814 indicates position information related to the current object distance position on the distance bar normalized for the entire length of the distance bar 805 that can be displayed at the camera display unit 206 .

[0171] Similar to the arrow 813 , the arrow 815 indicates position information related to the focus limit switch position on the distance bar normalized for the entire length of the distance bar 805 that can be displayed at the camera display unit 206 .

[0172] <About Example of Display Screen Related to Macro Magnification Information and Depth of Field Information on the Distance Bar>

[0173] although Figure 8An example of displaying object distance information is shown, but next, Figure 9 A display example in the case of displaying information other than the object distance information, such as macro magnification information and depth of field information, is shown.

[0174] State 901 shows a state in which macro magnification information is displayed in addition to object distance information. Similarly to the distance information, representative indicator values ​​and representative indicator positions are appropriately placed in the magnification information, making it easy for the user to visually confirm the representative indicator values ​​and representative indicator positions according to the specifications of the interchangeable lens. For example, icon 902 indicates the position of 1.2x macro magnification. Based on position information standardized to display "1.2x" on the distance bar as the position of display information acquired from the interchangeable lens 100, "1.2x" is located at the "3" position. Furthermore, "0.7x" is located at the "30" position as a standardized position. The camera microcomputer 205 acquires this information from the lens microcomputer 111 and displays it on the display unit 206.

[0175] Status 903 shows an example in which depth of field information indicating the focused area is displayed in addition to the current object distance information. The depth of field changes based on the aperture state. The smaller the aperture, the wider the depth of field. The depth of field is determined based on the permissible circle of confusion information (which serves as a guideline for determining whether the lens is focused) and the aperture, which indicates the amount of blur. Therefore, the camera microcomputer 205 obtains depth of field information from the current aperture information received from the lens microcomputer 111 and calculates the depth of field. For example, the camera microcomputer 205 calculates the focused area when the aperture is set to F / 8 or F / 22. Indicator 809 indicates the current object distance information. Indicator 904 indicates the index position of the depth of field area when the aperture value is set to F / 8.0. On the distance bar, icon 905 indicates that the index position is the depth of field position when the aperture value is set to F / 8.0. Then, range 906 indicates the depth of field area when the aperture value is set to F / 8.0. Similarly, indicator 907 indicates the index position of the depth of field area when the aperture value is set to F / 22. On the distance bar, an icon 908 indicates that the index position is the depth of field position when the aperture value is set to F22. Then, a range 909 indicates the depth of field area when the aperture value is set to F22.

[0176] <Startup Processing>

[0177] Next, we will refer to Figure 10 Camera startup processing in Figure 11A Stable operation processing and Figure 11B Flowchart of the display update process in the description will refer to Figure 8 and Figure 9 The display information described is sent from the interchangeable lens 100 to the camera body 200, and the display information is displayed at the camera body 200. First, referring to Figure 10 , the camera startup processing will be described below with regard to both the processing of the camera microcomputer 205 and the processing of the lens microcomputer 111.

[0178] In steps S1001 and S1021, negotiation communication processing is performed between the camera body 200 and the interchangeable lens 100. As negotiation communication, the camera body 200 transmits information about which functions the camera body 200 is compatible with to the interchangeable lens 100. Conversely, the interchangeable lens 100 transmits functional information about the functions included in the interchangeable lens 100 to the camera body 200. More specifically, the functional information is information about, for example, whether the interchangeable lens 100 has an image stabilization function, or whether the interchangeable lens 100 is compatible with the reference lens. Figure 4 、 Figure 5A 、 Figure 5B and Figure 5C Information describing compatibility between communication modes M2 and M3.

[0179] In step S1002, the camera microcomputer 205 determines whether, as a result of the communication processing in steps S1001 and S1021, communication in communication mode M2 ​​is possible using the combination of the camera microcomputer 205 and the interchangeable lens 100 currently attached to the camera microcomputer 205. In this exemplary embodiment, if communication in communication mode M2 ​​is not possible, processing for displaying the object distance information in the camera is not performed. Therefore, the camera microcomputer 205 transitions to a stable state. This is because the effective communication rate in communication mode M2 ​​is higher than that in communication mode M1, and therefore, as long as communication mode M2 ​​is selected, there is sufficient communication bandwidth. However, even if the combination of the camera microcomputer 205 and the interchangeable lens 100 is incompatible with communication mode M2 ​​and communication mode M1 is selected, processing for displaying the object distance information in the camera can be performed by devising a method, such as thinning out the communication frequencies based on the sufficient communication bandwidth. If it is determined that communication in the communication mode M2 ​​is possible ("Yes" in step S1002), then in steps S1003 and S1022, processing for switching to the communication mode M2 ​​is performed. Figure 6 The described method performs the switching process.

[0180] The following will describe the process by which the camera body 200 acquires information for displaying object distance information from the interchangeable lens 100 via communication. Terms are defined as follows. Information determined when the interchangeable lens 100 is attached to the camera body 200 (e.g., focal lengths at the telephoto and wide-angle ends, and the representative indicator position of the object distance information) is referred to as "static display information." Static display information is information that does not change depending on the status of the camera body 200 and the interchangeable lens 100 (such as operations on the camera and lens, and the image capture mode). On the other hand, display information that changes dynamically depending on the operation of the camera 200 (e.g., focus position) is referred to as "dynamic display information." Dynamic display information is information that changes depending on the status of the camera body 200 and the interchangeable lens 100 (such as operations on the camera and lens, and the image capture mode). Static display information is also referred to as "first information." Dynamic display information is also referred to as "second information."

[0181] In step S1004, the camera microcomputer 205 requests the data size of static display information required for displaying the object distance information from the interchangeable lens 100. A description is given of the static display information required for displaying the object distance information.

[0182] The static display information for displaying the object distance information on the display unit 206 of the camera includes information corresponding to the presence or absence of the operating member of the interchangeable lens 100 and information on the index display. Specifically, the static display information according to the present exemplary embodiment is, for example, the following parameters 1 to 12.

[0183] Information corresponding to whether an operating member exists

[0184] 1. Is there a switch for switching to macro photography?

[0185] 2. Is there a focus limit switch?

[0186] ●Information about indicator display

[0187] 3. Number of representative indicator locations expressed in meters

[0188] 4. The numerical value of the representative index in meters (as many as the number of representative index locations)

[0189] 5. Information on the standardized placement of representative indicators on the distance bar, expressed in meters (as many as the number of representative indicator locations)

[0190] 6. Number of representative indicator locations in feet

[0191] 7. The number of representative indicators in feet (as many as the number of representative indicator locations)

[0192] 8. Information on the standardized placement of representative indicators on the distance bar, expressed in feet (as many as the number of representative indicator locations)

[0193] 9. Number of representative index positions expressed by macro magnification

[0194] 10. Numerical values ​​of representative indicators expressed in terms of macro magnification (as many as the number of representative indicator positions)

[0195] 11. Information on the standardized placement of representative indicators on the distance bar expressed in terms of macro magnification (as many as the number of representative indicator positions)

[0196] 12. Information on the standardized placement of the "∞" mark on the distance bar

[0197] use Figure 8 The display examples in describe static display information.

[0198] First, the information "information corresponding to the presence or absence of an operating member" is described. This information indicates that the interchangeable lens 100 has a function corresponding to the operating member. Therefore, other information can be used instead, as long as the information corresponds to the presence or absence of a function related to the display. For example, the information "1. Presence of a selection switch for switching to a macro photography state" need only indicate that the interchangeable lens 100 can switch to a macro photography state. Furthermore, the information "2. Presence of a focus limit switch" need only indicate that the interchangeable lens 100 has a function for limiting the range of movement of the focus lens 104.

[0199] Regarding "1. Is there a selection switch for switching to the macro shooting state", there are interchangeable lens products that switch to the macro shooting mode by, for example, operating a switch (not shown) on the barrel while causing the zoom ring to hit the barrel as an operation on the lens barrel. This item indicates whether the interchangeable lens 100 includes such a selection switch for switching to the macro shooting state. In this proposal, when macro shooting is performed, the shooting magnification is displayed on the display unit 206 of the camera. Therefore, the display content can be switched by operating the switch. If the static display information indicates that there is no switch, communication control can be performed so as not to obtain display information when macro shooting is performed.

[0200] Regarding "2. Is there a focus limit switch?", there is an interchangeable lens product that includes a focus limit switch in the lens barrel, which limits the distance range at which the lens can focus. In this proposal, the limit status of the focus limit switch is displayed on the camera's display unit 206. If the static display information indicates the absence of the switch, communication control can be performed to prevent the display of information regarding the focus limit switch's indicator position.

[0201] exist Figure 8 In the example, since seven representative indicator positions are placed (i.e., "0.45m", "0.6m", "0.8m", "1m", "1.5m", "3m", and "5m"), the parameter "3. Number of representative indicator positions expressed in meters" is "7".

[0202] As referenced below Figure 10 As described above, when the lens 100 is attached, information about the above-mentioned terms 1 to 12 is collectively acquired. At this time, if the number of representative index values ​​is a fixed value, and if the number of representative index values ​​is not the maximum number, it is necessary to provide a blank in the communication content. On the other hand, as described above, the number of representative index positions is included in the communication content. Therefore, the camera that has received this information analyzes the order of received data based on the number of representative index positions, thereby extracting information about terms 1 to 12. This eliminates the need to perform communications that result in unnecessary blanks. More specifically, if the parameter "3. The number of representative index positions expressed in meters" is "7", the received data is received in the following order.

[0203] First byte: Whether there is a selection switch for switching to macro camera mode

[0204] Second byte: whether there is a focus limit switch

[0205] Third byte: Number of representative indicator positions in meters

[0206] Bytes 4 to 10: The numerical value of the representative indicator expressed in meters (when a single indicator value is expressed in one byte)

[0207] Bytes 11 to 17: Information about the standardized placement of the representative indicator on the distance bar expressed in meters (in the case of a single indicator value represented by one byte)

[0208] Therefore, the number of representative index positions is included in the communication content, whereby a plurality of pieces of data can be transmitted without intervals.

[0209] “4. Numerical values ​​of representative indices expressed in meters (as many as the number of representative indices positions)” are “0.45,” “0.6,” “0.8,” “1,” “1.5,” “3,” and “5.”

[0210] Then, regarding "5. Standardized placement position information of representative indicators on the distance bar expressed in meters (as many as the number of representative indicator positions)", a value standardized for a predetermined range (length) of the distance bar (an example of a display area) displayed at the display unit 206 is transmitted. The lens microcomputer 111 has information about where the representative indicator positions are placed on the distance bar. For example, as information about where the representative indicator position "0.6m" is placed on the distance bar, a value standardized when the entire length of the distance bar is 100 is transmitted. The predetermined range (length) serving as a reference may be predefined by the camera microcomputer 205 and the lens microcomputer 111, or may be acquired through communication. "0.45m" is located at the position of "3" as a standardized value relative to the nearest end. "0.6m" is located at the position of "15" as a standardized value relative to the nearest end. As Figure 8 As the length of the arrow 813 represented in , a value of "15" is set as a parameter.

[0211] This display position information can be determined from the perspective of the specifications and design of the interchangeable lens 100. For example, in order to display the index "0.45m" as the possible shooting distance (shortest focal length) of the interchangeable lens 100 and display the index "5m" before the "∞" mark on the infinity side, then based on how much display space the user wishes to provide on the closest side closer than "0.45m" and between the "5m" and "∞" marks in addition to the portion between "0.45m" and "5m" as a design, the position information regarding the index value can be determined within the standardized value 100.

[0212] Furthermore, in the case of the foot expression and the macro magnification expression, the index value is similarly transmitted as a normalized value.

[0213] If you focus on 3, 4, and 5, "3. The number of representative indicator positions expressed in meters" is information corresponding to the number of indicators. In addition, "4. The numerical value of the representative indicator expressed in meters (as many as the number of representative indicator positions)" is information corresponding to the numerical value to be displayed, which corresponds to the same number of indicators as indicated by the information corresponding to the number of indicators. In addition, "5. Standardized placement position information about the representative indicators on the distance bar expressed in meters (as many as the number of representative indicator positions)" is information corresponding to the position where the information corresponding to the numerical value is displayed. As described above, the information corresponding to the number of indicators, the information corresponding to the numerical value to be displayed (which corresponds to the same number of indicators as indicated by the information corresponding to the number of indicators), and the information corresponding to the position where the information corresponding to the numerical value is displayed form a set.

[0214] Also regarding 6, 7, and 8, the lens microcomputer 111 has the above-described set of information in foot expression, which is a unit system different from that of meter expression.

[0215] Furthermore, regarding 9, 10, and 11, the lens microcomputer 111 has the above-described information set in macro magnification expression which is a unit system different from the meter expression and the foot expression.

[0216] As described above, regarding information that varies depending on the unit system, the lens microcomputer 111 has information on each unit system.

[0217] "12. Information on the standardized placement of the "∞" mark on the distance bar", i.e. Figure 8 The placement of the "∞" mark in the distance bar is the same for any of the meter, foot, and macro magnification displays. Therefore, the parameter only needs to have a single common value.

[0218] The above parameters do not change dynamically. Therefore, the parameters are acquired when the camera body 200 with the interchangeable lens 100 attached is turned on (or when the interchangeable lens 100 is attached to the camera body 200 while the camera is operating). In step S1004, the camera microcomputer 205 inquires the interchangeable lens 100 about the data size of the communication data for static display information. This is because the number of representative indicators varies depending on the specifications of the interchangeable lens 100, and this is also to finalize the communication size in advance in order to transmit all static display information in communication mode M3, which has a higher effective communication rate.

[0219] In step S1023 , the lens microcomputer 111 generates static display information to be displayed at the display unit 206 of the camera body 200 , and responds to the camera microcomputer 205 with the data size of the static display information.

[0220] In steps S1005 and S1024, in order to obtain static display information at high speed and in total, the communication mode is switched to Figure 5A 、 Figure 5B and Figure 5C Communication mode M3, which has the highest effective communication speed, is described in [1]. In communication mode M3, the data communication direction of the communication terminal is switched. Therefore, the direction of the internal buffer is switched in sequence so that no data communication conflict occurs. Therefore, a process for switching the communication mode is required. Although a certain amount of processing time is required for the switching process, the communication time can be shortened when the communication volume is slightly large. On the contrary, if communication mode M3 is used when the communication volume is small, the process for switching the communication mode causes overhead, thereby extending the communication processing time. Since the data size of the static display information is somewhat large in this case, communication mode M3 can be used to shorten the communication time.

[0221] In step S1006, the camera microcomputer 205 transmits an acquisition request command to acquire static display information. In step S1025, the lens microcomputer 111, which has received the communication command, performs processing for normalizing the static display information generated in step S1023 to be displayed on the display unit 206 of the camera. This may only be necessary, for example, after the camera microcomputer 205 asserts the signal RTS and Figure 5A 、 Figure 5B and Figure 5C Alternatively, the standardization process may be performed simultaneously with the data generation process in step S1023.

[0222] In step S1026, the lens microcomputer 111 transmits the data subjected to the process for normalizing the static display information to the camera microcomputer 205 through the DLC communication channel. In step S1007, the camera microcomputer 205 receives the data.

[0223] In steps S1008 and S1027, the communication mode returns to communication mode M2. This is because the camera microcomputer 205 completes communication of a large amount of data (eg, items 1 to 13 described above) required for displaying static lens information that does not change dynamically in the processing of steps S1006, S1007, S1025, and S1026.

[0224] In step S1009 , the camera microcomputer 205 transmits the standardized static display information to a block (not shown) for controlling the camera display unit 206 .

[0225] In step S1010, the camera microcomputer 205 determines whether the display of distance information is set to "enabled" in the camera menu settings. If the display setting is disabled (No in step S1010), the distance information does not need to be displayed until the menu is set to "display enabled" again. Therefore, the camera microcomputer 205 transitions to a stable state. If the display setting is enabled in the menu (Yes in step S1010), the process proceeds to a process for transmitting and displaying dynamically changing object distance information in step S1011 and thereafter.

[0226] A description of the dynamic display information required to display object distance information is given.

[0227] The dynamic display information is information required to change the display state based on the state of the operating member of the camera body 200 or the interchangeable lens 100. In the present exemplary embodiment, the dynamic display information is, for example, the following parameters.

[0228] ● Information about whether to display

[0229] 1. Whether to display or hide object distance information

[0230] ●Information corresponding to the location

[0231] 2. Standardized position information about the current object distance on the distance bar

[0232] 3. Information on the standardized position of the focus limit on the infinity side of the distance bar

[0233] 4. Standardized position information about the focus limit on the closest side of the distance bar

[0234] 5. Information on the standardized position of the macro area on the distance bar

[0235] First, the "information regarding whether to display" will be described. For example, if the object distance information should be hidden, the lens microcomputer 111 notifies the camera microcomputer 205 of the information "1. Whether to display or hide the object distance information." For example, to avoid displaying a display that would be uncomfortable for the user if the drive of the focus lens 104 of the interchangeable lens 100 becomes irregular (for example, if the drive of the focus lens 104 is out of sync), the lens microcomputer 111 transmits "hide" to the camera microcomputer 205. As another exemplary embodiment, the lens microcomputer 111 may transmit "stop updating from the previous display state" instead of "hide" to the camera microcomputer 205. A configuration may be employed in which the "information regarding whether to display" further includes "whether to display or hide information regarding the drive state of the focus lens." By transmitting this information, icons 811 and 812 indicating the drive direction of the focus lens 104 can be displayed. In this case, information regarding the drive direction of the focus lens 104 may also be transmitted from the lens microcomputer 111 to the camera microcomputer 205 as necessary. Alternatively, "whether to display or hide information regarding the driving state of the focus lens in the infinity direction" and "whether to display or hide information regarding the driving state of the focus lens in the closest direction" may be transmitted as separate information. Furthermore, in a configuration in which an icon is displayed separately when performing the above-described regenerative drive, "whether to display or hide an icon regarding regenerative drive" may be transmitted from the lens microcomputer 111 to the camera microcomputer 205.

[0236] Next, "Information corresponding to position" is described. "2. Normalized position information about the current object distance on the distance bar" is information indicating the position relative to the object distance. Figure 8814. The lens microcomputer 111 can obtain absolute position information about the focus pulse based on the output information of the focus position detection sensor 140. The lens microcomputer 111 calculates the current focus pulse position as a normalized value based on the absolute position information about the focus pulse from the closest side to the infinite side and the position information about the pulse encoder.

[0237] "3. Standardized position information about the focus limit on the infinity end side on the distance bar" indicates the position of the focus limit relative to the infinity end side. Figure 8 The display position parameter is normalized over the entire length of the distance bar and corresponds to arrow 815.

[0238] In step S1011 , the camera microcomputer 205 transmits an acquisition request command to the lens microcomputer 111 to acquire dynamically changing display information.

[0239] In step S1028, the lens microcomputer 111 generates dynamically changing display information. The lens microcomputer 111 then performs processing to normalize the display information. In step S1029, the lens microcomputer 111 responds to the camera microcomputer 205 with the normalized display information as a communication result. In step S1012, the camera microcomputer 205 receives the response result.

[0240] In step S1013 , the camera microcomputer 205 transmits the display information dynamically changed and acquired in step S1012 to the camera display unit 206 as information for initially displaying the object distance information.

[0241] The importance of transmitting static display information in the communication mode M3 and dynamic display information in the communication mode M2 ​​is described.

[0242] The above process realizes communication and display processing when the camera is started, and then Figure 8 The initial display state is achieved as in the example shown.

[0243] <Stable operation processing>

[0244] Next, refer to Figure 11A and Figure 11B A description is given of the process of updating the display of object distance information when the camera is in a stable state.

[0245] Figure 11AThis is a flowchart showing the processing of the camera body 200 and the processing of the interchangeable lens 100 regarding the display of object distance information. This processing is executed by a program recorded in the camera microcomputer 205. The processing for displaying information is described with respect to both the processing of the lens communication control unit 110 that communicates with the interchangeable lens 100 and the processing of the camera display unit 206 that performs display processing.

[0246] First, the processing of the camera display unit 206 is described.

[0247] In steps S1101 and S1121, Figure 10 As described in the startup processing in , static display information and dynamic display information from the interchangeable lens 100 as initial values ​​for display are sent from the lens communication control unit 110 to the camera display unit 206.

[0248] In step S1102, the camera display unit 206 determines whether the camera menu status is set to "display subject distance information" or "not display subject distance information." If the setting is set to "not display subject distance information" ("No" in step S1102), the display process is not performed. Therefore, the camera display unit 206 waits for the menu setting to be changed. If the setting is set to "display subject distance information" ("Yes" in step S1102), the process proceeds to step S1103.

[0249] In step S1103, the camera display unit 206 displays the static display information and the dynamic display information as the initial values ​​acquired in step S1101 from the lens communication control unit 110. The positions of the representative index value 806 and the current object distance position 809 of these display information are relative positions when the entire length of the focus bar is 100. More specifically, when the display position of the representative index value "0.8" of the focal length is "20", the representative index value "0.8" is displayed at a position of 100 pixels relative to the entire length of the focus bar (i.e., 500 pixels).

[0250] In step S1104, in order to determine whether to update the display of dynamic display information as a subsequent process, the camera display unit 206 reconfirms the display setting. After performing the display update process in step S1107, it is then determined in this step whether to continue the display update process.

[0251] In step S1105, the camera display unit 206 determines whether a notification for clearing the static and dynamic display information is given by the lens communication control unit 110. If a clear notification for clearing the display is given ("Yes" in step S1105), the camera display unit 206 clears the display state of the display unit 206 in step S1106. In step S1108, the camera display unit 206 waits for static display information to be sent again from the lens communication control unit 110. If no notification for clearing the display is given ("No" in step S1105), the process proceeds to the display update processing in step S1107. Figure 11B The subroutine in describes this process.

[0252] Next, the processing of the communication control unit 110 of the interchangeable lens 100 will be described.

[0253] In step S1121 , the communication control unit 110 transmits the static display information and the dynamic display information to the camera display unit 206 as initial values.

[0254] In step S1122, the communication control unit 110 determines whether the interchangeable lens 100 has been detached. If the interchangeable lens 100 has been detached (Yes in step S1122), the communication control unit 110 sends a notification for clearing the static and dynamic display information to the camera display unit 206. This is because when the lens is detached, the display of the camera display unit 206 needs to be hidden, and then, if another interchangeable lens 100 is attached, it must be displayed based on the specifications of the attached interchangeable lens 100.

[0255] In step S1124 , the communication control unit 110 waits until the camera microcomputer 205 confirms a state in which the lens is attached in the communication I / F circuit 208 .

[0256] In step S1125, Figure 10 Initial communication processing between the camera microcomputer 205 and the lens microcomputer 111 described in . By this processing, static display information and dynamic display information are acquired as initial values ​​corresponding to the specifications of the interchangeable lens 100, and the display processing starting from step S1121 is performed again.

[0257] If the lens 100 continues to be attached in step S1122 ("No" in step S1122), the processing proceeds to step S1126. In step S1126, the communication control unit 110 determines whether it is necessary to update the object distance information about the interchangeable lens 100. For example, while the menu is displayed, if the distance bar for displaying the object distance is not displayed, it is determined as "No" ("No" in step S1126), and the processing proceeds to step S1128. If it is determined that the display needs to be updated ("Yes" in step S1126), the processing proceeds to step S1127. In step S1127, the communication control unit 110 performs processing for acquiring dynamic display information from the interchangeable lens 100 and sends the dynamic display information to the camera display unit 206. However, if it is not necessary to update the display ("No" in step S1126), the processing proceeds to step S1128. In step S1128, the communication control unit 110 does not perform communication processing with the interchangeable lens 100.

[0258] refer to Figure 12 , describing the communication processing in steps S1127 and S1128.

[0259] Figure 12 This is a timing chart of the lens communication control process performed between the camera microcomputer 205 and the lens microcomputer 111, with the horizontal axis representing elapsed time and the vertical axis representing communication items. In this example, communication control during live view is shown. Alternatively, viewfinder imaging can also be used.

[0260] The imaging synchronization signal 1201 indicates the start timing of the accumulation control 1202 of the image sensor 201. The imaging synchronization signal 1201 is generated in a cycle corresponding to the frame rate. For example, if control is performed at 60 fps, the vertical synchronization signal 1210 is input to the camera microcomputer 205 in a cycle of 16.6 ms. The timing 1211 indicates the center of gravity timing of the accumulation control 1202 of the image sensor 201.

[0261] Item 1203 indicates synchronization signal communication for sharing exposure timing between the camera body 200 and the interchangeable lens 100. The communication is performed using a vertical synchronization signal 1210 as a trigger. Figure 12 Among the various communication processes shown, those indicated by shaded areas are those subject to timing restrictions. If a delay occurs in the synchronization signal communication process 1220, there may be a discrepancy between the camera microcomputer 205 and the lens microcomputer 111 in determining the exposure timing. Therefore, communication must be performed within predetermined timing restrictions. The communication for displaying the object distance information implemented by this exemplary embodiment must be performed so as not to affect this timing-restricted communication process.

[0262] Item 1204 is a communication process for the image stabilization function, in which the camera microcomputer 205 and the lens microcomputer 111 operate in conjunction with each other. For example, an example is shown in which two communication processes 1221 and 1222 are performed for one frame. There is a timing restriction in which communication 1222 is performed before or at a predetermined timing, starting from the center of gravity timing 1211 of the accumulation control 1202 of the image sensor 201.

[0263] Item 1205 is a communication process for automatic focus control. For example, process 1223 is a communication process for acquiring parameters for correcting the defocus amount or information on the current state of the focus lens 104 from the interchangeable lens 100. For example, process 1224 is a communication process for the camera microcomputer 205 to request the lens microcomputer 111 to drive the focus ring for focusing.

[0264] Item 1206 is a communication process for automatic exposure (AE) control. For example, process 1225 is a communication process for acquiring current optical information (e.g., aperture value for exposure control) from the interchangeable lens 100. Process 1226 is a communication process in which the camera microcomputer 205 requests the lens microcomputer 111 to drive the aperture.

[0265] Item 1207 is a data communication process for displaying the object distance, and is a communication for acquiring dynamically changing display information from the interchangeable lens 100. Ideally, as Figure 12 As shown, all communication processing should be performed in one frame. However, for example, in a case where there is no margin in the communication band, data communication for AE is arranged to be performed every two frames. In the present exemplary embodiment, an example of periodically transmitting dynamic display information has been described. However, the present disclosure is not limited to this, as long as a display according to the change can be performed when the dynamic display information changes. For example, the lens microcomputer 111 can detect that the dynamic display information changes. Then, based on the detection, the lens microcomputer 111 can notify the camera microcomputer 205 that a change in the dynamic display information has been detected, thereby transmitting the dynamic display information only when necessary.

[0266] Next, refer to Figure 11B , a description is given of the display update processing of the camera display unit 206 in step S1107.

[0267] In step S1140, the camera display unit 206 determines whether a timeout has occurred when the display state of the object distance is set to hidden based on the timer. This mode will be described below in step S1146. If the determination is made as to whether the display is to be maintained based on the timeout ("No" in step S1140), the process proceeds to step S1142. If the determination is made as to whether the display is to be hidden ("Yes" in step S1140), the process proceeds to step S1154.

[0268] In step S1142, the camera display unit 206 determines the setting status of the display menu regarding how to display information. In this exemplary embodiment, the menu can be set to display the subject distance information in one of the following modes: "Always display when MF is in progress," "Display for a predetermined period of time when focus is adjusted," "Always display," and "Not display." If the menu display setting is "Always display when MF is in progress," processing proceeds to step S1143. If the menu display setting is "Display for a predetermined period of time when focus is adjusted," processing proceeds to step S1146. If the menu display setting is "Always display," processing proceeds to step S1149. If the menu display setting is "Not display," this subroutine ends.

[0269] In step S1143, the camera microcomputer 205 determines whether the interchangeable lens 100 notifies the camera microcomputer 205 of the AF state or the MF state as the state of the lens focus switch set in the lens barrel. As another exemplary embodiment, the camera microcomputer 205 may confirm the menu setting status in a form in which the AF state and the MF state are switched in the camera menu. If the state is the AF state (No in step S1143), the process proceeds to step S1151. If the state is the MF state (Yes in step S1143), the process proceeds to step S1144.

[0270] In step S1144 , based on the latest dynamic display information, the camera microcomputer 205 performs display update processing for updating the display of the object distance information (distance bar information) at the display unit 206 .

[0271] In step S1146 , the camera microcomputer 205 clears the timer for erasing the display of the object distance using the bar.

[0272] The processing of step S1147 is similar to the processing of step S1144.

[0273] In step S1148 , in order to hide the distance bar of the object distance information for a predetermined time, the camera microcomputer 205 sets a timer for erasing the object distance information.

[0274] If the setting of the menu is assigned to "always display" in step S1142, the process proceeds to step S1149. The processing content of step S1149 is similar to the processing content of step S1144.

[0275] If the display setting of the menu is a setting other than “non-display”, then in step S1151 , the camera microcomputer 205 makes a determination to notify the user that the focus is at the closest end or the infinite end.

[0276] More specifically, the camera microcomputer 205 determines the "normalized position information regarding the current object distance on the distance bar" included in the dynamic display information. If the position information indicates the closest end position, the process proceeds to step S1152. If the position information indicates the infinite end position, the process proceeds to step S1153. If the position information indicates neither the closest end nor the infinite end, this subroutine ends.

[0277] In step S1152, the camera microcomputer 205 changes the color of the focus movement direction icon 812 to gray. This allows the user to recognize that the focus does not change even if the focus ring is further rotated to the closest side during manual focus operation.

[0278] In step S1153, the camera microcomputer 205 changes the color of the focus movement direction icon 811 to gray. This allows the user to recognize that the focus does not change even if the focus ring is further rotated to the "∞" side during manual focus operation.

[0279] If it is determined in step S1140 that the display state of the object distance is set to be hidden based on the timer (YES in step S1140), the processing proceeds to step S1154. In step S1154, the camera microcomputer 205 hides the object distance. Figure 8 Various object distance information described in .

[0280] Through the aforementioned communication method between the imaging device and the accessory device, and the aforementioned display processing on the imaging device, the position of the information regarding the object distance to be displayed on the imaging device is transmitted to the imaging device as a standardized numerical value via communication. This allows for optimal display regardless of the imaging device being attached to an accessory device of a different specification.

[0281] Furthermore, when an accessory device is attached, data related to a proportional display for displaying object distance information is acquired. Then, in a stable state, only the dynamically changing object distance information for the accessory device is acquired, minimizing the communication load. This reduces the impact on various types of control, such as AF control, AE control, and image stabilization control, and also enables frequent communication for displaying the subject (such as at every vertical signal timing). Consequently, various types of drive control can be performed, enabling the display of object distance information without delay.

[0282] In the first exemplary embodiment, a case has been described in which the object distance information detected by the lens microcomputer 111 is displayed on the display unit 206 of the camera body 200, and a case in which macro magnification information or depth of field information is further displayed. In the second exemplary embodiment, a case has been described in which the camera microcomputer 205 acquires camera shake status information obtained by the vibration sensor of the vibration gyro and detected by the lens microcomputer 111 through communication, and displays the camera shake status information on the display unit 206.

[0283] Various components of the camera body 200 and the interchangeable lens 100 , startup processing, and communication processing in a stable state are similar to those of the first exemplary embodiment and thus will not be described here.

[0284] In the display of camera shake information implemented in this exemplary embodiment, this exemplary embodiment differs from the first exemplary embodiment in terms of items transmitted as dynamic display information and static display information and control regarding display.

[0285] In the present exemplary embodiment, in addition to the static display information described in the first exemplary embodiment, the lens microcomputer 111 transmits the following information to the camera microcomputer 205 as static display information for displaying a camera shake state.

[0286] 1. Whether a vibration gyroscope is present in the interchangeable lens 100

[0287] That is, the camera microcomputer 205 transmits information indicating that the camera microcomputer 205 has a function of detecting a camera shake condition to the lens microcomputer 111 as information corresponding to the presence or absence of the function.

[0288] Then, in the present exemplary embodiment, information to be acquired as dynamic display information is switched according to the display object. If the display object is “camera shake condition”, the lens microcomputer 111 transmits the following information to the camera microcomputer 205 as dynamic display information.

[0289] 1. Vibration detection value in the pitch direction of the vibration gyroscope

[0290] 2. Vibration detection value in the yaw direction of the vibration gyroscope

[0291] That is, the lens microcomputer 111 transmits a detection value obtained by detecting a camera shake state to the camera microcomputer 205. On the other hand, if the display target is not the “camera shake condition”, the lens microcomputer 111 transmits the static display information described in the first exemplary embodiment to the camera microcomputer 205.

[0292] First, refer to Figure 13 , which describes the display content of the camera shake condition.

[0293] Status 1301 shows an example of the detection status of the current camera shake amount. In this information display, the camera microcomputer 205 acquires camera shake status information obtained by the shake sensor of the vibration gyro of the interchangeable lens 100 via communication and displays the camera shake status information on the display unit 206. Status 1302 indicates the vibration status in the pitch direction, and a meter 1303 indicates the vibration level. Similarly, status 1304 indicates the vibration status in the yaw direction, and a meter 1305 indicates the vibration level.

[0294] Next, the control flow for display will be described.

[0295] This exemplary embodiment uses the method described in the reference section except step S1127 in the communication process of the interchangeable lens 100 and step S1107 in the process of the camera display unit 206. Figure 10 Describes the startup process flow and references Figure 11A The flow of the described stable operation process is similar to that of the first exemplary embodiment. Therefore, similar parts will not be described here. Figure 14 , a description is given of the subroutine processing of the display update processing of the camera display unit 206 in step S1107.

[0296] If the subroutine in step S1107 is started, in step S1401, the camera display unit 206 determines a timeout condition when the display state of the camera shake condition is set to hidden based on the timer. This mode will be described below in step S1406.

[0297] In step S1402, the camera display unit 206 determines whether the subject to be displayed on the display unit 206 is the "camera shake condition" in the camera menu setting. If the display menu is set to "camera shake condition" ("Yes" in step S1402), in step S1403, the camera display unit 206 also determines the setting status of the display menu regarding how to display information. Similar to the first exemplary embodiment, the display style of the camera shake condition can be set to "always display when performing MF", "display for a predetermined time when adjusting the focus", "always display", and "not display".

[0298] If the menu display setting is "Always display when MF is in progress," the process proceeds to step S1404. If the menu display setting is "Display for a predetermined time when focus is adjusted," the process proceeds to step S1406. If the menu display setting is "Always display," the process proceeds to step S1409. If the menu display setting is "Not display," the subroutine ends.

[0299] In step S1404, the camera microcomputer 205 determines whether the interchangeable lens 100 notifies the camera microcomputer 205 of the AF state or the MF state as the state of the lens focus switch set in the lens barrel. As another exemplary embodiment, the camera microcomputer 205 may confirm the menu setting status in a form in which the AF state and the MF state are switched in a camera menu. If the state is the AF state (No in step S1404), the subroutine ends. If the state is the MF state (Yes in step S1404), the camera microcomputer 205 displays the camera shake status in step S1405.

[0300] In step S1406 , the camera microcomputer 205 clears a timer for eliminating a camera shake condition.

[0301] The processing of step S1407 is similar to the processing of step S1405.

[0302] In step S1408 , in order to conceal the camera shake condition for a predetermined time, the camera microcomputer 205 sets a timer for eliminating the camera shake condition.

[0303] If the setting of the menu is assigned to "always display" in step S1403, the process proceeds to step S1409. The processing content of S1409 is similar to the processing content of step S1405.

[0304] If the camera shake condition display timer times out in step S1401 (YES in step S1401 ), then in step S1410 , the camera microcomputer 205 hides the camera shake condition.

[0305] If the display item is not “camera shake condition” in step S1402 (NO in step S1402 ), then in step S1411 , the camera microcomputer 205 proceeds to processing for displaying the object distance information described in the first exemplary embodiment.

[0306] Next, we will refer to Figure 15 The lens communication control unit processing according to the present exemplary embodiment is described. However, as described above, except for step S1127, the processing is similar to that in the first exemplary embodiment.

[0307] If it is determined in step S1126 that the display in the camera status needs to be updated (YES in step S1126 ), then the processing proceeds to step S1501 .

[0308] In step S1501, the lens communication control unit 110 determines whether the target to be displayed is the "camera shake condition" in the camera menu. If the display target is the "camera shake condition" ("Yes" in step S1501), in step S1502, the lens communication control unit 110 sets the dynamic display information to be acquired from the lens microcomputer 111 to the following values ​​required to display the "camera shake condition".

[0309] 1. Vibration detection value in the pitch direction of the vibration gyroscope

[0310] 2. Vibration detection value in the yaw direction of the vibration gyroscope

[0311] If the display target is not the “camera shake condition” but the “object distance information” (NO in step S1501 ), in step S1503 , the lens communication control unit 110 sets the information to be acquired from the lens microcomputer 111 as the following information required to display the object distance information described in the first exemplary embodiment.

[0312] 1. Whether to display or hide object distance information

[0313] 2. Standardized position information about the current object distance on the distance bar

[0314] 3. Information on the standardized position of the focus limit on the infinity side of the distance bar

[0315] 4. Standardized position information about the focus limit on the closest side of the distance bar

[0316] 5. Information on the standardized position of the macro area on the distance bar

[0317] More specifically, a communication command for acquiring the “camera shake status” and a communication command for acquiring the “object distance information” are defined based on the camera menu and are appropriately used.

[0318] As described above, in this exemplary embodiment, when an accessory device is attached, data related to a proportional display of subject distance information, which varies depending on the accessory device's specifications, and information required for displaying camera shake conditions are acquired. Furthermore, in a stable state, dynamically changing subject distance information and camera shake information related to the accessory device are exclusively acquired. Therefore, during stable operation, only dynamically changing parameters required for display are transmitted. This reduces communication bandwidth usage and minimizes system load, thereby preventing delays in acquiring display information from the accessory device.

[0319] In the first exemplary embodiment, the case where the object distance information detected by the lens microcomputer 111 is displayed on the display unit 206 of the camera body 200, and the case where macro magnification information or depth of field information is further displayed has been described. In the third exemplary embodiment, a case is described where, if the interchangeable lens 100 is a zoom lens, the camera microcomputer 205 acquires information about the zoom position through communication and displays the information on the display unit 206.

[0320] The various components of the camera body 200 and the interchangeable lens 100, the startup process, and the communication process in the stable state are similar to those of the first exemplary embodiment and are therefore not described here. However, in order to display the zoom position, some items are additionally acquired as static display information.

[0321] That is, in addition to the above-mentioned items described in the first exemplary embodiment, the lens microcomputer 111 also transmits the following items to the camera microcomputer 205 .

[0322] 13. Number of representative indicator positions when zoom position is displayed on the bar

[0323] 14. Numerical values ​​of representative indicators when zoom positions are displayed on the bar (as many as the number of representative indicator positions)

[0324] 15. Standardized placement position information for representative indicators on the zoom bar when zoom positions are displayed on the bar (as many as the number of representative positions)

[0325] As described above, the static display information according to this exemplary embodiment also includes "information regarding indicator display" for each zoom position. That is, the static display information according to this exemplary embodiment includes a set of information corresponding to the number of indicators, information corresponding to numerical values ​​to be displayed (corresponding to as many indicators as indicated by the information corresponding to the number of indicators), and information corresponding to the position at which the information corresponding to the numerical values ​​is to be displayed.

[0326] Then, in the present exemplary embodiment, information to be acquired as dynamic display information is switched according to the display object. If the display object is “zoom position”, the lens microcomputer 111 transmits the following information to the camera microcomputer 205 as dynamic display information.

[0327] ● Standardized placement information on the zoom bar when the current zoom position is displayed on the bar

[0328] That is, the lens microcomputer 111 transmits information corresponding to the current position of the zoom lens as “information corresponding to the position” to the camera microcomputer 205. On the other hand, if the display target is not the “zoom position”, the lens microcomputer 111 transmits the static display information described in the first exemplary embodiment to the camera microcomputer 205.

[0329] First, refer to Figure 16 , gives a description of the display content when the zoom position is displayed on the bar.

[0330] Status 1601 shows an example of displaying the current zoom position. Icon 1602 indicates the zoom direction toward the wide-angle side, and icon 1603 indicates the zoom direction toward the telephoto side. Bar 1604 displays the entire area of ​​the bar from the telephoto end to the wide-angle end. Similar to the display of object distance information, icon 1605 indicates focal length information as a representative indicator value for the zoom position. This display example illustrates the case of a lens with specifications where the focal length can be zoomed from 70mm to 300mm. Similar to the display of object distance information in the first exemplary embodiment, position information normalized for the entire length of the zoom bar is obtained from the interchangeable lens 100 to determine which numerical values ​​are displayed as these representative indicators and at what positions. For example, "70mm" is displayed at position "3" relative to the entire length of the zoom bar, and "135mm" is displayed at position "50" relative to the entire length of the zoom bar. Icon 1606 indicates the current zoom position. The camera microcomputer 205 acquires the icon 1606 as normalized zoom position information from the lens microcomputer 111 and displays the icon 1606 on the display unit 206 .

[0331] <Control Flow for Display>

[0332] Next, the control flow for display will be described.

[0333] This exemplary embodiment uses the method described in the reference section except step S1127 in the communication process of the interchangeable lens 100 and step S1107 in the process of the camera display unit 206. Figure 10 Describes the startup process flow and references Figure 11A The flow of the described stable operation process is similar to that of the first exemplary embodiment. Therefore, similar parts will not be described here. Figure 17 , a description is given of the subroutine processing of the display update processing of the camera display unit in step S1107.

[0334] If the subroutine in step S1107 is started, then in step S1701, the camera display unit 206 determines a timeout state when the display state of the zoom position is set to hidden based on a timer. This mode will be described in step S1706.

[0335] In step S1702, the camera display unit 206 determines whether the subject to be displayed on the display unit 206 is the "zoom position" in the camera menu settings. If the display menu is set to "zoom position" ("Yes" in step S1702), in step S1703, the camera display unit 206 further determines the setting status of the display menu regarding how to display information. Similar to the first exemplary embodiment, the display style of the zoom position can be set to "constantly display when performing MF," "display for a predetermined period of time when adjusting the focus," "constantly display," and "not display."

[0336] If the menu display setting is "Always display when MF is in progress," the process proceeds to step S1704. If the menu display setting is "Display for a predetermined time when focus is adjusted," the process proceeds to step S1706. If the menu display setting is "Always display," the process proceeds to step S1709. If the menu display setting is "Not display," this subroutine ends.

[0337] In step S1704, the camera microcomputer 205 determines whether the interchangeable lens 100 notifies the camera microcomputer 205 of the AF state or the MF state as the state of the lens focus switch set in the lens barrel. As another exemplary embodiment, the camera microcomputer 205 may confirm the menu setting status in a form in which the AF state and the MF state are switched in a camera menu. If the state is the AF state ("No" in step S1704), this subroutine ends. If the state is the MF state ("Yes" in step S1704), the camera microcomputer 205 displays the zoom position information in step S1705.

[0338] In step S1706 , the camera microcomputer 205 clears the timer for eliminating the zoom position information.

[0339] The processing of step S1707 is similar to the processing of step S1705.

[0340] In step S1708 , in order to hide the zoom position information for a predetermined time, the camera microcomputer 205 sets a timer for erasing the zoom position information.

[0341] If the setting of the menu is assigned to "always display" in step S1703, the process proceeds to step S1709. The processing content of S1709 is similar to that of step S1705.

[0342] If the zoom position information display timer times out in step S1701 (YES in step S1701 ), then in step S1710 , the camera microcomputer 205 hides the zoom position information.

[0343] If the display item is not “zoom position” in step S1702 (NO in step S1702 ), then in step S1711 , the camera microcomputer 205 proceeds to processing for displaying the object distance information described in the first exemplary embodiment.

[0344] Next, we will refer to Figure 18 The lens communication control unit processing according to the present exemplary embodiment is described. However, as described above, the processing of steps S1121 to S1125 is similar to that in the first exemplary embodiment.

[0345] If the interchangeable lens 100 continues to be attached to the camera body 200 in step S1122 (NO in step S1122 ), the processing proceeds to step S1801 .

[0346] In step S1801, the communication control unit 110 determines whether the optical information about the attached lens 100 has changed. If an intermediate accessory is attached between the interchangeable lens 100 and the camera body 200, there is a case where the optical information about the lens 100 has changed. For example, an expander is built into some models of the interchangeable lens 100. The optical information (including the focal length) about the interchangeable lens 100 is changed by activating the built-in expander. For example, Figure 16 An external appearance 1630 as an example of a product form of the interchangeable lens 100 is shown. Figure 16The various operating members 150 to 153 in the interchangeable lens 100 are similar to those in the first exemplary embodiment. Operating member 1631 is used to switch the expander built into the interchangeable lens 100. Operating member 1631, acting as a selection switch, can select three states: "No expander," "1.4x expander enabled," and "2.0x expander enabled."

[0347] In the case where optical information changes due to a change in the attachment state of the expander described above, information acquired for still display also needs to be updated when the lens 100 has been attached or when the camera is started with the lens 100 attached.

[0348] Therefore, if it is determined in step S1801 that the optical information has changed ("Yes" in step S1801), then in step S1802, the communication control unit 110 obtains static display information and dynamic display information from the interchangeable lens 100 as initial values, and sends the static display information and dynamic display information as initial values ​​to the display unit 206 again.

[0349] If it is determined in step S1803 that the display in the camera status needs to be updated (YES in step S1803 ), then the processing proceeds to step S1804 .

[0350] In step S1804, the lens communication control unit 110 determines whether the target to be displayed is the "zoom position" in the camera menu. If the display target is the "zoom position" ("Yes" in step S1804), then in step S1805, the lens communication control unit 110 sets the dynamic display information to be acquired from the lens microcomputer 111 as the "normalized placement position information on the zoom bar when the current zoom position is displayed on the bar" required for displaying the "zoom position." If the display target is not the "zoom position" but the "object distance information" ("No" in step S1804), then in step S1806, the lens communication control unit 110 sets the information to be acquired from the lens microcomputer 111 as the following information required for displaying the object distance information described in the first exemplary embodiment.

[0351] 1. Whether to display or hide object distance information

[0352] 2. Standardized position information about the current object distance on the distance bar

[0353] 3. Information on the standardized position of the focus limit on the infinity side of the distance bar

[0354] 4. Standardized position information about the focus limit on the closest side of the distance bar

[0355] 5. Information on the standardized position of the macro area on the distance bar

[0356] More specifically, a communication command for acquiring “zoom position information” and a communication command for acquiring “object distance information” are defined and appropriately used according to the camera menu.

[0357] refer to Figure 16 , a description is given of the display contents in the case where the built-in 1.4x expander is enabled, and in the case where the built-in 2.0x expander is enabled in step S1801, for example.

[0358] State 1610 shows an example of displaying the current zoom position with the 1.4x extender enabled. Icon 1611 indicates the focal length at the wide-angle end. When the extender is not present, the focal length at the wide-angle end is 70mm, and icon 1611 indicates 98mm, which is 1.4 times 70mm.

[0359] Icon 1612 indicates the focal length on the telephoto side. When the extender is not present, the focal length on the telephoto side is 300mm, and icon 1612 indicates 420mm, which is 1.4 times 300mm. In this case, if representative index values ​​are displayed at the wide-angle end and the telephoto end of the zoom, a fraction such as 98mm is displayed under the premise of high visibility. However, in the portion where 135mm is displayed in the absence of the extender, if a fraction such as 189mm (i.e., 1.4 times 135mm) is displayed, the display becomes complicated. In response, the interchangeable lens 100 generates information as static display information as well as standardized position information to intentionally display the position of "200mm".

[0360] Through the aforementioned communication method between the camera and the accessory device, and the aforementioned display processing within the camera, the position of the zoom position information to be displayed within the camera is transmitted to the camera as a standardized numerical value. This allows for optimal display regardless of the camera being used, even when the accessory device has different specifications.

[0361] Furthermore, in this exemplary embodiment, when an accessory device is attached, data regarding a proportional display for displaying zoom position information is acquired. Then, in a stable state, only dynamically changing object distance information regarding the accessory device is acquired. Furthermore, communication processing is selectively performed based on whether the display target is object distance information or zoom position information, thereby minimizing the communication load. This reduces the impact on various types of control, such as AF control, AE control, and image stabilization control, and also enables frequent communication for displaying the subject (such as at each vertical signal timing). Consequently, various types of drive control can be performed and object distance information can be displayed in the display without delay. Furthermore, even if optical information changes during operation, the information required for proportional display is acquired and displayed again, and when the optical information changes, the indicator is optimally displayed for the optical state after the change. Consequently, a display that facilitates visual confirmation can be achieved.

[0362] According to the embodiments of the present disclosure, information based on an interchangeable lens can be appropriately displayed at a camera display unit.

[0363] Other embodiments

[0364] The embodiments of the present invention can also be implemented by the following method, that is, providing software (program) that performs the functions of the above-mentioned embodiments to a system or device through a network or various storage media, and the computer or central processing unit (CPU) or microprocessing unit (MPU) of the system or device reads and executes the program.

[0365] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. An accessory device that is attachable to an imaging apparatus including a display unit and includes a focus lens for changing a focus lens position, the display unit including a display area that displays distance information corresponding to the focus lens position, the accessory device comprising: a communication control unit configured to control communication with the imaging device via the communication unit, Wherein, the communication control unit sends: first information indicating the amount of distance information displayed in association with the display area; second information indicating distance information of a quantity indicated by the quantity; and Third information indicating data sizes corresponding to the first information and the second information.

2. The accessory device according to claim 1, wherein: The communication control unit further sends the following information along with the first information and the second information: Fourth information indicating a position of each distance information relative to the display area.

3. The accessory device according to claim 1, wherein: Symbols at infinity are not counted as the amount of distance information.

4. The accessory device according to claim 2, wherein: The communication control unit further sends the following information along with the first information and the second information: Fifth information indicating distance information corresponding to a current position of the focus lens.

5. The accessory device according to claim 4, wherein: In a case where the display unit performs display corresponding to first distance information which is distance information corresponding to the focus lens position, and in a case where the focus lens position changes, the communication control unit transmits information indicating second distance information different from the first distance information as the fifth information.

6. The accessory device according to claim 2, wherein: The communication control unit transmits the first information, the second information, and the fourth information through communication performed corresponding to power supply.

7. The accessory device according to claim 6, wherein: Even when the operation member is operated, the communication control unit does not retransmit the first information, the second information, and the fourth information.

8. The accessory device of claim 1, wherein: the communication control unit performs communication in a first communication format or a second communication format different from the first communication format, and The communication control unit sends the first information, the second information, and fourth information indicating the position of each distance information relative to the display area in the first communication format, and sends fifth information indicating the distance information corresponding to the focus lens position in the second communication format.

9. The accessory device according to claim 8, wherein: the communication control unit performs communication via a first communication terminal, a second communication terminal, and a third communication terminal included in the communication unit, transmits data through a third communication channel through the third communication terminal in accordance with a change in a signal level in a first communication channel through the first communication terminal, and receives data through a second communication channel through the second communication terminal in accordance with the transmission of the data, wherein, in the second communication format, the communication control unit maintains a signal level in the third communication channel at a predetermined level, thereby notifying the imaging device of a busy state, and In the first communication format, the communication control unit does not notify the camera of the busy state.

10. The accessory device of claim 1, wherein the accessory device is a lens unit.

11. An imaging apparatus capable of attaching an accessory device including a focus lens for changing a position of the focus lens, the imaging apparatus comprising: a display unit comprising a display area for displaying distance information corresponding to a position of the focus lens; as well as a communication control unit configured to control communication with the accessory device via the communication unit, The communication control unit receives: first information indicating the amount of distance information displayed in association with the display area; second information indicating distance information of a quantity indicated by the quantity; as well as Third information indicating data sizes corresponding to the first information and the second information.

12. The imaging device according to claim 11, wherein The communication control unit also receives the following information along with the first information and the second information: Fourth information indicating a position of each distance information relative to the display area.

13. The imaging device according to claim 11, wherein Symbols at infinity are not counted as the amount of distance information.

14. The imaging device according to claim 12, wherein The communication control unit also receives the following information along with the first information and the second information: Fifth information indicating distance information corresponding to a current position of the focus lens.

15. The imaging device according to claim 14, wherein In a case where the display unit performs display corresponding to first distance information which is distance information corresponding to the focus lens position, and in a case where the focus lens position changes, the communication control unit receives information indicating second distance information different from the first distance information as the fifth information.

16. The imaging device according to claim 15, wherein The communication control unit receives the first information, the second information, and the fourth information through communication performed corresponding to power supply.

17. The imaging device according to claim 16, wherein Even when the operation member is operated, the communication control unit does not receive the first information, the second information, and the fourth information again.

18. The imaging device according to claim 14, wherein the communication control unit performs communication in a first communication format or a second communication format different from the first communication format, and The communication control unit receives the first information, the second information, and fourth information indicating the position of each distance information relative to the display area in the first communication format, and receives fifth information indicating the distance information corresponding to the current position of the focusing lens in the second communication format.

19. The imaging device according to claim 18, wherein the communication control unit controls communication to perform communication via a first communication terminal, a second communication terminal, and a third communication terminal included in the communication unit, receives data through a third communication channel through the third communication terminal according to a change in a signal level in a first communication channel through the first communication terminal, and transmits data through a second communication channel through the second communication terminal according to reception of the data, wherein, in the second communication format, a signal level in the third communication channel is maintained at a predetermined level, thereby notifying the camera apparatus of a busy state, and In the first communication format, the busy state is not notified to the imaging device.

20. The imaging apparatus according to claim 11, wherein The accessory device is a lens unit.

21. A control method for controlling an accessory device, the accessory device being attachable to an imaging apparatus including a display unit and including a focus lens for changing a focus lens position, the display unit including a display area displaying distance information corresponding to the focus lens position, the control method comprising: controlling communication with the imaging device via a communication unit, Among them, in the control of communication, the following information is sent: first information indicating the amount of distance information displayed in association with the display area; second information indicating distance information of a quantity indicated by the quantity; and Third information indicating data sizes corresponding to the first information and the second information.

22. A method for controlling an imaging apparatus, the imaging apparatus being capable of attaching an accessory device including a focus lens for changing a focus lens position, the imaging apparatus including a display unit including a display area displaying distance information corresponding to the focus lens position, the method comprising: controlling communication with the accessory device via the communication unit, Among them, in the control of communication, the following information is received: first information indicating the amount of distance information displayed in association with the display area; second information indicating distance information of a quantity indicated by the quantity; and Third information indicating data sizes corresponding to the first information and the second information.

23. A computer program product comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements the control method according to claim 21 or 22.

Images