Adapter device, imaging device, and control method thereof

Abstract

To appropriately perform communication even when the configuration for notification or communication is different between a camera and an accessory.SOLUTION: A control unit 201 controls a signal level of a contact TA15 according to a first command received from an imaging device via a contact TA08 and a signal level indicated from an accessory device via a contact TA203, in a first communication mode. The control unit 201 receives a second command indicating a second communication mode and data via the contact TA08 in the second mode. The control unit transmits the data via the contact TA102 after the reception. The control unit 201 controls communication in the second communication mode according to the signal level of the contact TA15 and the second command.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to communication between a camera and an accessory attached to the camera. [Background technology]

[0002] It is known to attach accessories such as a flash unit via an accessory shoe provided on a camera, and there is also known an adapter that is attached between the camera and the accessory such as a flash unit to relay the connection between the camera and the accessory.

[0003] Patent Document 1 discloses a technology that allows a strobe to be attached to an adapter and wirelessly controls the strobe using the adapter. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2010-529749 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Document 1 does not consider that the configurations for notification and communication are different between the camera and the strobe.

[0006] Therefore, the present invention aims to provide an adapter device, an imaging device, and a control method for these that can communicate appropriately even if the configurations for notification and communication between the camera and the accessory are different. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, one aspect of the present invention is an adapter device attached between an imaging device and an accessory device, the adapter device having a control means for controlling communication with the imaging device via a first contact, a second contact, and a third contact, and communication with the accessory device via a fourth contact and a fifth contact, the control means transmitting data via the fourth contact in response to receiving data from the first contact, or transmitting data via the second contact in response to receiving data via the fifth contact. Through The communication device has a first communication mode for controlling the transmission of data and a second communication mode different from the first communication mode, and in the second communication mode, after receiving a second command and data via the first contact, transmits the data via a fourth contact, and the control means is configured to execute communication in the first communication mode in response to connection detection communication of the accessory device in the second communication mode and a first command corresponding to an instruction to transition to the first communication mode.

[0008] Another aspect of the present invention is an adapter device attached between an imaging device and an accessory device, the adapter device having a control means for controlling communication with the imaging device via a first contact, a second contact, and a third contact, and communication with the accessory device via a fourth contact and a fifth contact, the control means transmitting data via the fourth contact in response to receiving data from the first contact, or transmitting data via the second contact in response to receiving data via the fifth contact. Through The communication device has a first communication mode for controlling the transmission of data and a second communication mode different from the first communication mode, and in the second communication mode, after receiving a second command and data via the first contact, transmits the data via a fourth contact, and the control means is configured to execute communication in the first communication mode in response to connection detection communication of the accessory device in the second communication mode and a first command corresponding to an instruction to transition to the first communication mode. [Effects of the Invention]

[0009] According to the present invention, even if the configurations for notification and communication differ between the camera and the accessory, appropriate communication can be performed. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing the configuration of a camera, an adapter, and a strobe in a first embodiment. [Figure 2] FIG. 4 is a diagram showing an operation sequence when an adapter is connected to the camera in the first embodiment. [Figure 3] 4A to 4C are diagrams illustrating a flash photography operation of the camera in the first embodiment. [Figure 4] FIG. 2 is a diagram illustrating communication between a camera, an adapter, and a strobe in the first embodiment. [Figure 5] 5A to 5C are diagrams illustrating acquisition of the charge state of a strobe in the first embodiment. [Figure 6] FIG. 4 is a diagram showing an interrupt signal from a strobe to a camera in the first embodiment. [Figure 7] FIG. 3 is a diagram illustrating light emission control from the camera to the strobe in the first embodiment. [Figure 8] 10A to 10C are diagrams illustrating a flash photography operation in the second embodiment. [Figure 9] 10A to 10C are diagrams illustrating a camera connection detection operation of the flash in the second embodiment. [Figure 10] 10A and 10B are diagrams illustrating a strobe connection detection operation of the adapter in the second embodiment. [Figure 11] 10A and 10B are diagrams illustrating a charging voltage detection operation of the strobe in the second embodiment. [Figure 12] 10A and 10B are diagrams illustrating an operation when an adapter in the second embodiment acquires the charging state of a flash device. [Figure 13] 10A and 10B are diagrams illustrating the flash emission operation at the time of pre-emission of the camera, adapter, and strobe in the second embodiment. [Figure 14] 10A and 10B are diagrams illustrating flat light emission operations during pre-emission of a camera, an adapter, and a strobe in the second embodiment. [Figure 15] 10A and 10B are diagrams illustrating flash emission operations during main emission of the camera, adapter, and strobe in the second embodiment. [Figure 16] 10A and 10B are diagrams illustrating flat light emission operations during main light emission of a camera, an adapter, and a strobe in the second embodiment. [Figure 17] 10A and 10B are diagrams illustrating an interrupt operation of a strobe to a camera in the second embodiment. [Figure 18] 10A and 10B are diagrams illustrating an interrupt operation of the adapter to the camera in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] <<First Embodiment>> Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] FIG. 1 shows the electrical configuration of a camera 100 as an electronic device according to an embodiment of the present invention, an adapter 200 detachably attached to the camera 100, and an external device 300 (a strobe 300 in this embodiment) attached to the adapter 200. The adapter 200 and the strobe 300 are examples of accessories attached to the camera 100. The accessory is also referred to as an accessory device. Note that in this embodiment, a strobe is used as an example of the external device 300, but some or all of the control of this embodiment may be applied to accessories other than strobes. The strobe and adapter are also referred to as accessory devices. If the adapter is not defined separately from the accessory device, the adapter may be included in the accessory device. The adapter is also referred to as an intermediate accessory.

[0013] <Configuration of camera 100> The camera 100 and the adapter 200 are electrically connected by one-to-one contact between the plurality of contacts (terminals) TC01 to TC21 of the camera connection section 141 and the plurality of contacts TA01 to TA21 of the adapter connection section 211, respectively.

[0014] The camera 100 is supplied with power from a battery 111. The battery 111 is detachable from the camera 100. The camera control unit A101 and the camera control unit B102, which serve as control means for the camera 100, are circuits that control the entire camera 100, and are configured by a microcomputer with a built-in CPU and the like.

[0015] The camera control unit A101 monitors switches for operating the camera (not shown) and other devices. It operates even when the camera is in standby mode (low power consumption mode) and controls the system power supply in response to user operations. The camera control unit B102 controls the image sensor 122, display unit 127, and other devices, and stops operating when the camera is in standby mode (low power consumption mode).

[0016] The system power supply unit 112 is a circuit that generates power to be supplied to each circuit of the camera 100, and is composed of a DC-DC converter circuit, an LDO (Low Drop Out), a charge pump circuit, etc. A voltage of 1.8V generated by the system power supply unit 112 is constantly supplied from the battery 111 to the camera control unit A101 as the camera microcomputer power supply VMCU_C.

[0017] In addition, several types of voltages generated by the system power supply unit 112 are supplied to the camera control unit B102 at any timing as a camera microcomputer power supply VMCU2_C. The camera control unit A101 controls the system power supply unit 112 to perform on / off control of the power supply to each circuit of the camera 100.

[0018] The optical lens 121 is detachable from the camera 100. Light from a subject incident through the optical lens 121 is imaged on an image sensor 122, which may be a CMOS sensor, a CCD sensor, or the like. The subject image formed on the image sensor 122 is encoded into a digital image signal.

[0019] The image processing unit 123 performs image processing such as noise reduction and white balance processing on the digital imaging signal to generate image data, and converts the image data into an image file in JPEG format or the like for recording in the recording memory 126.

[0020] Furthermore, the image processing unit 123 generates VRAM image data from the image data to be displayed on the display unit 127 .

[0021] The memory control unit 124 controls the sending and receiving of image data and other data generated by the image processing unit 123 etc. The volatile memory 125 is a memory capable of high-speed reading and writing, such as a DDR3 SDRAM, and is used as a workspace for image processing performed by the image processing unit 123 etc.

[0022] The recording memory 126 is a readable and writable recording medium such as an SD card or a CFexpress card that can be attached to and detached from the camera 100 via a connector (not shown).

[0023] Display unit 127 is a display arranged on the back of camera 100, and is configured with an LCD panel, an organic EL display panel, etc. Backlight unit 128 adjusts the brightness of display unit 127 by changing the amount of light from the backlight of display unit 127.

[0024] The accessory power supply unit A131 and the accessory power supply unit B132, which serve as power supply means, are each a voltage conversion circuit that converts the voltage supplied from the system power supply unit 112 into a predetermined voltage, and in this embodiment generate 3.3V as the accessory power supply VACC.

[0025] The accessory power supply unit A131 is a power supply unit with low self-power consumption, which is composed of an LDO etc. The accessory power supply unit B132 is a circuit composed of a DC / DC converter circuit etc., which is capable of passing a larger current than the accessory power supply unit A131.

[0026] The accessory power supply unit B132 consumes more power than the accessory power supply unit A131.

[0027] For this reason, when the load current is small, the accessory power supply unit A131 is more efficient than the accessory power supply unit B132, and when the load current is large, the accessory power supply unit B132 is more efficient than the accessory power supply unit A131.

[0028] The camera control unit A101 controls the on / off of the voltage output of the accessory power supply unit A131 and the accessory power supply unit B132 according to the operating state of the adapter 200.

[0029] The protection circuit 133 as a protection means is configured with a current fuse element, a polyswitch element, or an electronic fuse circuit that combines a resistor, an amplifier, and a switch element, etc. When the power supply current value supplied to the adapter 200 from the accessory power supply unit A 131 and the accessory power supply unit B 132 exceeds a predetermined value and becomes excessive (abnormal), the protection circuit 133 outputs an overcurrent detection signal DET_OVC.

[0030] In this embodiment, the protection circuit 133 is an electronic fuse circuit, and notifies the camera control unit A101 with an overcurrent detection signal DET_OVC when a current of 1 A or more flows. The overcurrent detection signal DET_OVC indicates an overcurrent by going to a Hi level.

[0031] The camera connection unit 141 is a connector for electrically connecting with the adapter 200 via 21 contacts TC01 to TC21 arranged in a row. The contacts TC01 to TC21 are arranged in this order from one end to the other in the arrangement direction.

[0032] TC01 is connected to ground (GND) and serves not only as a reference potential contact but also as a contact that controls the wiring impedance of differential signals D1N and D1P.

[0033] The differential signal D1N connected to TC02 and the differential signal D1P connected to TC03 are differential data communication signals that perform data communication in pairs and are connected to the camera control unit B102. TC02, TC03, and TC07 to TC17, TC19, and TC20, which will be described later, are communication contacts.

[0034] TC04 is connected to GND and serves as a contact point for the reference potential between the camera 100 and the adapter 200. TC04 is disposed on the outside of TC05, which will be described next, in the arrangement direction of the contact points.

[0035] An accessory power supply VACC generated by accessory power supply units A131 and B132 is connected to TC05 as a power supply contact via a protection circuit 133.

[0036] The accessory attachment detection signal / ACC_DET is connected to TC06, which serves as the attachment detection contact. The accessory attachment detection signal / ACC_DET is pulled up to the camera microcontroller power supply VMCU_C via resistor element Rp134 (10 kΩ).

[0037] The camera control unit A101 can detect whether the adapter 200 is attached by reading the signal level of the accessory attachment detection signal / ACC_DET.

[0038] If the signal level (potential) of the accessory attachment detection signal / ACC_DET is Hi level (predetermined potential), the adapter 200 is detected as not being attached, and if it is Lo level (GND potential as described below), the adapter 200 is detected as being attached.

[0039] SCLK connected to TC07, MOSI connected to TC08, MISO connected to TC09, and CS connected to TC10 are signals used by the camera control unit B102 as the communication master to perform SPI communication. When CS is asserted, SPI communication is enabled. In this embodiment, the low level of CS is the assert level, but the high level may also be the assert level. Data transmission by the camera control unit B via MOSI and data transmission from the adapter control unit 201 via MISO are executed in synchronization with the clock signal transmitted from the camera control unit B via SCLK. In this embodiment, an example will be described in which the data communicated here is 8-bit data. The signals communicated by the camera control unit B via SCLK, MOSI, MISO, and CS are also referred to as serial communication signals 151.

[0040] A communication request signal / WAKE is connected to TC11 for requesting communication from the adapter 200 to the camera control unit A101.

[0041] The communication request signal / WAKE is pulled up to the camera microcomputer power supply VMCU_C via a resistor. The camera control unit A101 can receive a communication request from the adapter 200 by detecting the falling edge (assertion) of the communication request signal / WAKE.

[0042] The SDA connected to TC12 and the SCL connected to TC13 are signals for the camera control unit A101 to perform I2C communication as the communication master. The signal communicated by the camera control unit A using SDA and SCL is also referred to as a serial communication signal 152.

[0043] SDA and SCL are open-drain communications pulled up to the camera microcomputer power supply VMCU_C, and in this embodiment the communication frequency is 100 kbps.

[0044] The FNC1 signal connected to TC14, the FNC2 signal connected to TC15, the FNC3 signal connected to TC16, and the FNC4 signal connected to TC17 are function signals whose functions can be changed depending on the type of accessory attached.

[0045] TC18 is also connected to GND, and is a contact point that serves as the reference potential for the camera 100 and the adapter 200, similar to TC04.

[0046] The differential signal D2N connected to TC19 and the differential signal D2P connected to TC20 are data communication signals that perform data communication as a pair, and are connected to the camera control unit B102.

[0047] TC21 is connected to GND and serves not only as a reference potential contact but also as a contact that controls the wiring impedance of the differential signals D2N and D2P.

[0048] <Adapter 200 configuration> An adapter control unit 201 serving as a control means for the adapter 200 is a circuit that receives commands from the camera and controls the entire adapter 200. It may be configured by a microcomputer including a CPU or the like.

[0049] The adapter control unit 201 also has a level shift function to change the output voltage of each to a voltage level that can be received by the receiving side so that the camera 100 and the strobe 300 can communicate with each other. Furthermore, the adapter control unit 201 has a function to detect the state of the strobe 300 and convert it into a state that can be determined by the camera 100. These functions will be described in detail later.

[0050] Adapter power supply unit 202 is a circuit that generates power to be supplied to each unit of adapter 200. A voltage generated by adapter power supply unit 202 is supplied to adapter control unit 201. By controlling adapter power supply unit 202, on / off control of power supply to each circuit of adapter 200 is performed.

[0051] In this embodiment, the adapter 200 operates only with power supplied from the camera 100 .

[0052] The adapter connection section 211 is a connector for electrically connecting with the camera 100 via 21 contacts TA01 to TA21 arranged in a row. The contacts TA01 to TA21 are arranged in this order from one end to the other in the arrangement direction.

[0053] TA01 is connected to GND.

[0054] TA02 and TA03 have no electrical connection to the inside of adapter 200 in this embodiment.

[0055] TA04 is connected to GND and serves as a contact point for the reference potential between the camera 100 and the adapter 200. TA04 is disposed on the outside of TA05, which will be described next, in the arrangement direction of the contact points.

[0056] The adapter power supply unit 202 is connected to the power contact TA05, and the accessory power supply VACC supplied from the camera 100 is connected to the adapter power supply unit 202.

[0057] TA06, which serves as an attachment detection contact, is directly connected to GND. When the adapter 200 is attached to the camera 100, the accessory attachment detection signal / ACC_DET described above is set to the GND level (ground potential) as a Lo level, thereby enabling the camera 100 to detect that the adapter 200 is attached.

[0058] SCLK connected to TA07, MOSI connected to TA08, MISO connected to TA09, and CS connected to TA10 are signals used by adapter control unit 201 to perform SPI communication as a communication slave. The signals communicated by adapter control unit 201 using SCLK, MOSI, MISO, and CS are also referred to as serial communication signals 251.

[0059] A communication request signal / WAKE is connected to TA11, which is used by the adapter control unit 201 to request communication from the camera 100. When the adapter control unit 201 determines that communication with the camera 100 is necessary, it issues a communication request to the camera 100 by outputting (asserting) the communication request signal / WAKE at Lo.

[0060] The SDA connected to TA12 and the SCL connected to TA13 are signals for the adapter control unit 201 to function as a communication slave and perform I2C communication. The signal communicated by the adapter control unit 201 using SDA and SCL is also referred to as a serial communication signal 252.

[0061] The FNC1 signal connected to TA14 and the FNC2 signal connected to TA15 are respectively connected as signals XON and ST_DET to the adapter control unit 201 within the adapter 200. The functions of these signals will be described later.

[0062] TA16 is a contact for transmitting an FNC3 signal, and TA17 is a contact for transmitting an FNC4 signal. In this embodiment, a case is illustrated in which TA16 and TA17 are not electrically connected to the inside of adapter 200. The contacts themselves may not be provided.

[0063] TA18 is also connected to GND, and serves as a reference potential contact point between the camera 100 and the adapter 200, similar to TA04.

[0064] TA19 and TA20 are terminals for transmitting differential signals, but in this embodiment, a case is illustrated in which there is no electrical connection to the inside of the adapter 200. Contacts themselves may not be provided.

[0065] TA21 is connected to GND.

[0066] The external device connection unit 212 is a connector terminal for connecting to the external device 300, and is also referred to as an adapter connection unit 212. In this embodiment, the external device 300 is a flash unit, hereinafter referred to as the flash unit 300.

[0067] These are signals for SPI communication, with the camera control unit B102 acting as the communication master, via SCLK_ST connected to TA101, MOSI_ST connected to TA102, and MISO_ST connected to TA103. Data transmission by the adapter control unit via MOSI_ST and data transmission by the strobe control unit 301 via MISO_ST are executed in synchronization with the clock signal transmitted from the adapter control unit via SCLK_ST. In this embodiment, an example will be described in which the data communicated here is 8-bit data. The signals communicated by the adapter control unit 201 via SCLK_ST, MOSI_ST, and MISO_ST are also referred to as serial communication signals 261.

[0068] The connection detection circuit 203 detects an external connection Department The connection detection circuit 203 is a circuit for detecting the connection of an external device 300 to the adapter control unit 201. The adapter control unit 201 detects the external connection by receiving an output signal from the connection detection circuit 203. Department It is possible to detect an external device connection to 212.

[0069] TA104 is a terminal for detecting the state of the strobe 300 using the connected signal CCC.

[0070] The current detection circuit 204 detects the current sunk by the strobe 300 and outputs a detection status signal CCC_I to the adapter control unit 201. Details will be described later.

[0071] The voltage detection circuit 205 detects the voltage output by the strobe 300 and outputs a detection status signal CCC_V to the adapter control unit 201. Details will be described later.

[0072] TA105 is a light emission trigger signal when the strobe 300 emits light, and is connected to the drain of the FET 206. The FET 206 switches in response to a signal XON_FET from the adapter control unit 201.

[0073] TA106 is connected to GND.

[0074] <Configuration of Strobe 300> The strobe 300 is connected to the adapter 200 via a strobe connector 308 .

[0075] The strobe control unit 301 adapter The control unit 200 controls each part in the strobe 300 based on the control from the camera 100 and user operations received via the control unit 200.

[0076] The strobe 300 has a battery 302 , and a strobe power supply unit 303 connected thereto generates power to be supplied to each unit within the strobe 300 .

[0077] The strobe charging unit 304 charges the strobe 300 with a voltage for emitting light.

[0078] The strobe light emitting unit 305 emits light using the voltage charged in the strobe charging unit 304 .

[0079] The voltage detection circuit 306 detects the voltage level of MOSI_ST output by the adapter 200, and outputs the detected state to the strobe control unit 301. Details will be described later.

[0080] Current source 307 has a function of notifying adapter 200 of the charging state of strobe charging unit 304. When strobe control unit 301 detects that the charging state of strobe charging unit 304 is such that it can emit light, it controls current source 307 to sink a predetermined current.

[0081] The base of the transistor 309 is connected to the signal XOUT from the adapter 200, and when the FET 206 turns on, the transistor 309 turns on and outputs / XOUT=H to the strobe control unit 301.

[0082] <Communication between camera 100 and adapter 200> FIG. 2 shows the operation flow of this embodiment.

[0083] In S801, the adapter 200 is connected to the camera 100, the accessory detection signal / ACC_DET becomes valid, and the camera 100 detects that the adapter 200 is attached.

[0084] In S802, the camera 100 starts outputting power for the accessory.

[0085] In S803, the adapter 200 asserts the communication request signal / WAKE to notify the camera 100 that communication is permitted.

[0086] In step S804, the camera 100 sends a communication request using the serial communication signal 152 to acquire accessory information of the adapter 200.

[0087] In S805, the adapter 200 transmits the accessory information to the camera 100 using the serial communication signal 252.

[0088] The accessory information includes information indicating that the adapter 200 is an adapter accessory for using the strobe 300, and that the signals FNC1 and FNC2 are used to control the strobe. The operation of the signals FNC1 and FNC2 will be described later.

[0089] In S806, the camera 100 checks the accessory information and determines that the connected adapter 200 is a relay accessory for using the strobe 300.

[0090] In S807, the camera 100 uses the serial communication signal 151 to perform initial communication with the adapter 200 to communicate with the strobe 300. The initial communication includes commands for setting the power supply to each block, which allows the accessor control unit 201 to detect that the strobe 300 has been attached.

[0091] S808 The adapter 200 receives a communication request signal / WAKE The adapter 200 then transitions to a state in which it waits for a communication request from the flash unit 300.

[0092] <Flowchart explaining the operation of the camera 100> The operation of the camera 100 according to the first embodiment of the present invention will be described below with reference to Fig. 3. Fig. 3 is a flowchart showing an example of flash photography. Note that the following steps are executed appropriately by the camera control unit B. For example, the camera control unit B is controlled by executing a program stored in a memory (not shown) in a CPU.

[0093] In step S200, the camera controller B determines via the adapter 200 whether the strobe 300 is connected.

[0094] If the strobe 300 is connected, the process proceeds to step S201, where the camera control unit B acquires strobe information from the strobe 300 via the adapter 200. The acquired information includes information necessary for strobe photography, such as the light emission mode and light emission amount set in the strobe 300.

[0095] Step S200 of Strobe connection detection and The acquisition of strobe information in step S201 will be described later with reference to FIG.

[0096] In step S202, the camera control unit B acquires strobe charging information from the strobe 300.

[0097] In step S203, the camera control unit B determines the charging state of the flash 300 based on the obtained flash charging information.

[0098] The operation of the strobe 300 and the adapter 200 according to the charging state of the strobe 300 will be described later with reference to FIG.

[0099] If it is determined that the flash is being charged, the process proceeds to step S204 as "flash charging OK." On the other hand, if it is determined in step S203 that the flash is not being charged, the process proceeds to step S205 as "flash charging NG."

[0100] In steps S204 and S205, camera control unit B controls the camera to perform an AE operation. The AE operation is a process of calculating the brightness of the subject area from a signal obtained from the image sensor 122 and determining the exposure parameters for shooting. The exposure parameters include the ISO sensitivity, shutter speed, and lens aperture value. The difference between steps S204 and S205 is whether or not the strobe 300 is to be fired when determining the exposure parameters. In step S204, camera control unit B determines the exposure parameters assuming that the strobe 300 will be fired.

[0101] On the other hand, in step S205, the camera control unit B determines the exposure parameters assuming that the strobe 300 will not emit light.

[0102] For example, in step S204, taking into consideration the possibility of blown-out highlights in the captured image due to light emitted from the strobe 300 (saturation of the image sensor 122), the upper limit of the ISO sensitivity is set lower than the ISO sensitivity determined in step S205.

[0103] In step S206, the camera control unit B controls the strobe 300 to emit light and perform an exposure operation. The strobe emission operation will be described later with reference to FIG.

[0104] <Detection of attachment of strobe via adapter 200 and corresponding communication> The operations of determining whether a flash is connected, acquiring flash information, and communicating with the flash in steps S200 and S201 will be described using Fig. 4. The flash information includes flash model identification information, flash setting information, and the like.

[0105] First, the camera 100 transmits a command 1 for the adapter 200 using the serial communication signal 151 (T30). The command 1 for the adapter 200 is a command for starting the serial communication signal 261 of the adapter 200. Upon receiving the command 1 for the adapter 200, the adapter control unit 201 sets the voltage levels of SCLK_ST and MOSI_ST to VSTH (T31).

[0106] When the voltage detection circuit 306 in the strobe 300 detects that the voltage level of MOSI_ST is greater than the threshold value Vth_ST2, it asserts C_DET300. When C_DET300 is asserted, the strobe control unit 301 determines that the camera 100 is connected, and sets the voltage level of MISO_ST to VSTL (T32).

[0107] When the voltage detection circuit 203 in the adapter 200 detects that the voltage level of MISO_ST is higher than the threshold value Vth_ST3, it asserts ST_DET200 (T32).

[0108] When ST_DET200 is asserted, the adapter control unit 201 determines that the strobe 300 is connected, asserts ST_DET(FNC2), and notifies the camera 100 that the strobe 300 has been connected.

[0109] Through the above process, the camera control unit B detects that the strobe 300 is connected. This connection detection communication is also referred to as connection detection communication. In this way, the adapter 200 converts the strobe connection detection information based on the output voltage level of the strobe 300 into a digital signal, eliminating the need for the camera 100 to have a mechanism for detecting analog information.

[0110] When camera 100 detects that a strobe is connected, it sends command 2 for adapter 200 using serial communication signal 151 to control the strobe (T33). When adapter 200 receives command 2 for adapter 200, it is set to a mode (strobe communication mode) in which the output voltages of the camera 100 and strobe 300 are level-shifted to a voltage level that can be received by the receiving side, so that communication between the camera 100 and strobe 300 is possible (T34). In this way, command 2 for adapter 200 is a command corresponding to an instruction to transition to strobe communication mode.

[0111] The H level of SCLK_ST, MOSI_ST, and MISO_ST is VSTH, and the L level is VSTL, and the threshold values ​​for the H and L levels are Vth_ST1. VSTL is higher than Vth_ST2 and Vth_ST3. Therefore, even if MOSI_ST and MISO_ST are VSTL, the adapter 200 and the strobe 300 can detect that they are connected.

[0112] When not in communication (SCLK_ST=H fixed), if MISO_ST is at the VSTH level, the strobe 300 is in a communication-enabled state, and if it is at the VSTL level, the strobe 300 is in a communication-disabled (busy) state.

[0113] At timing T35 in FIG. 4, when the initial settings associated with mounting a camera inside the strobe 300 are completed and communication with the camera becomes possible, the strobe 300 sets MISO_ST to the VSTH level. When MISO_ST changes to the VSTH level, the adapter 200 changes MISO to the H level. The camera 100 confirms that the strobe 300 has exited the Busy state when MISO changes to the H level. T36 is the state in which the camera 100 has started communication with the strobe 300. At timing T37, the strobe control unit 301 sets MISO_ST to the VSTL level to analyze the received communication and outputs the Busy state. At timings T38 and T39, the camera 100 again confirms that the strobe 300 has exited the Busy state and starts the next communication.

[0114] After the camera 100 has performed a series of communications to control the strobe 300, it negates CS (T40). When CS is negated, the adapter control unit 201 cancels the strobe communication mode, and the voltage levels of SCLK_ST and MOSI_ST are set to the VSTH level regardless of the states of SCLK and MOSI. In addition, the output of MISO is set to the L level regardless of the state of MISO_ST.

[0115] <Strobe charging status notification> The operation of the adapter control unit 201 to detect the charging state of the strobe 300 will be described with reference to FIG.

[0116] When the strobe control unit 301 detects that the charging state of the strobe charging unit 304 is in a state where it can emit light, it controls the current source 307 to sink a predetermined current. When the current detection circuit 204 detects that the current sunk by the strobe 300 is greater than a predetermined current threshold CCC_I_TH, it sets the detection state signal CCC_I to a high level.

[0117] The camera 100 communicates with the adapter 200 using serial communication signal 151 at predetermined times, such as the timing of light emission control, to check the charging state of the strobe 300. When the adapter control unit 201 receives communication to check the charging state of the strobe 300, it transmits the state of the detection state signal CCC_I to the camera 100.

[0118] <Transmission of communication request from strobe> The operation of notifying the camera 100 of a communication request from the strobe 300 via the adapter 200 will be described with reference to FIG.

[0119] When requesting communication from the camera 100, the flash control unit 301 applies a predetermined voltage to the CCC terminal. When the voltage detection circuit 205 detects that the voltage is greater than a predetermined voltage threshold CCC_V_TH, it sets the detection status signal CCC_V to high level. When the adapter control unit 201 detects that the detection status signal CCC_V is high level, it asserts / WAKE as an interrupt signal output to the camera 100.

[0120] The camera 100 starts communication with the flash control unit 301 by an interrupt operation using / WAKE.

[0121] Control of the X signal for strobe light emission will be described with reference to FIG.

[0122] To fire the strobe, the camera 100 asserts FNC1 (XON).

[0123] When XON is asserted, the adapter control unit 201 sets the signal XON_FET to high level, turns on the FET 206, and sets the signal XOUT to low level. When the signal XOUT goes low level, the transistor 309 of the strobe 300 turns on, and the signal / XOUT goes high level. When the strobe control unit 301 detects that the signal / XOUT is high level, it starts a predetermined light emission operation.

[0124] As described above, according to this embodiment, even if the configurations for notification and communication differ between the camera and the accessory, appropriate communication can be performed.

[0125] Furthermore, the adapter has a mode for level-shifting the communication signal between the camera and the strobe, and a mode for outputting the terminal state of the strobe to the camera via communication, so that the camera can obtain various types of strobe information.

[0126] <<Second embodiment>> A second embodiment of the present invention will now be described. In the second embodiment, it is assumed that the automatic light adjustment mode is set. In the automatic light adjustment mode, a pre-flash is emitted to the subject, and the appropriate light emission amount (main light emission amount) for actual imaging is calculated based on the result of light reflected from the subject received by the imaging sensor 122, and imaging (exposure) is performed with appropriate exposure. The configurations of the camera 100, adapter 200, and strobe 300 are the same as those described in FIG. 1. Furthermore, the operation when the adapter 200 is connected to the camera 100 is the same as that described in FIG. 2.

[0127] FIG. 8 is a flowchart for explaining flash photography in the automatic light adjustment mode.

[0128] Communication with the strobe 300 via the adapter 200 will be described with reference to FIG. 4, as in the first embodiment.

[0129] In step S300, the camera 100 transmits a command 1 for the adapter 200 using the serial communication signal 151 (FIG. 4: T30).

[0130] Command 1 for adapter 200 is a command for starting serial communication signal 261 of adapter 200 .

[0131] Upon receiving command 1 for the adapter 200, the adapter control unit 201 sets the voltage levels of SCLK_ST and MOSI_ST to VSTH (FIG. 4: T31).

[0132] At T31, when the voltage detection circuit 306 in the strobe 300 detects that the voltage level of MOSI_ST is higher than the threshold value Vth_ST2, it asserts C_DET300. The control flowchart in the strobe 300 at this time is shown in FIG.

[0133] In step S400 of FIG. 9, when the flash control unit 301 detects that C_DET300 is asserted, it determines that the camera 100 is connected, and the process proceeds to step S401.

[0134] In step S401, the flash control unit 301 sets the voltage level of MISO_ST to VSTL (FIG. 4: T32).

[0135] At T32, when the voltage detection circuit 203 in the adapter 200 detects that the voltage level of MISO_ST is higher than the threshold value Vth_ST3, it asserts ST_DET200. The control flowchart in the adapter 200 at this time is shown in FIG.

[0136] In step S500 of FIG. 10, when the adapter control unit 201 detects that ST_DET200 is asserted, it determines that the strobe 300 is connected, and the process proceeds to step S501.

[0137] In step S501, the adapter control unit 201 asserts ST_DET(FNC2) to notify the camera 100 that the strobe 300 has been connected.

[0138] In step S301, if the camera 100 detects that a strobe is connected because ST_DET(FNC2) is asserted, the process proceeds to step S302. On the other hand, if it determines that ST_DET(FNC2) is not asserted and that a strobe is not connected, the process proceeds to step S306. In step S306, as described for step S205 in Figure 3, the camera 100 determines exposure parameters assuming that the strobe 300 will not fire.

[0139] In step S302, the camera 100 performs periodic communication with the strobe 300 via the adapter 200. Periodic communication is communication in which the camera 100 transmits setting information and the like to the strobe 300 and receives setting information and the like from the strobe 300. The operations during communication are the operations from T33 to T40 in the above-mentioned Figure 4. When periodic communication is complete, the camera 100 proceeds to step S303.

[0140] In step S303, the camera 100 acquires flash charging information.

[0141] FIG. 11 is a flowchart showing the process performed by the flash unit 300 when monitoring the charging state.

[0142] In step S600, the flash control unit 301 compares the voltage charged in the flash charging unit 304 with a predetermined threshold value. If the voltage is greater than the predetermined threshold value, the process proceeds to step S601, where charging control is turned off. Then, in step S602, the current source 307 is controlled to sink a predetermined current.

[0143] On the other hand, if the voltage is smaller than the predetermined threshold value, the process proceeds to step S603, where charging control is turned on, and then in step S604, the current source 307 is turned off.

[0144] The flash control unit 301 periodically executes the control shown in FIG. 11 to control charging.

[0145] In step S303, the camera 100 communicates with the adapter 200 using the serial communication signal 151, thereby obtaining the state of the detection state signal CCC_I.

[0146] In step S304, the camera control unit B determines the charging state of the flash 300 based on the obtained flash charging information.

[0147] If it is determined that the flash is being charged, the process proceeds to step S305 as "flash charging OK." On the other hand, if it is determined in step S304 that the flash is not being charged, the process proceeds to step S306 as "flash charging NG."

[0148] In steps S305 and S306, the camera control unit B performs control to perform the AE operation. In step S305, the camera control unit B determines the exposure parameters assuming that the strobe 300 will emit light.

[0149] On the other hand, in step S306, the camera control unit B determines the exposure parameters assuming that the strobe 300 will not emit light.

[0150] In step S307, the camera control unit B monitors the release button (not shown), and if the release button is pressed (ON), the process proceeds to step S308 to proceed with the process for photographing. On the other hand, if the release button is not pressed, the camera control unit B returns the process to step S301 and repeats the processes from step S301 to step S307.

[0151] In steps S308, S309, and S310, camera control unit B checks the connection and charging status of the flash. The connection of the flash is checked in the same manner as in S301. The charging status is checked in the same manner as in S308, or the result of the determination in S308 is used. If the flash is not connected or the flash cannot be charged, the process proceeds to step S319.

[0152] In step S319, the camera control unit B determines the exposure parameters assuming that the strobe 300 will not emit light, and in step S320, the exposure operation is performed without emitting light from the strobe.

[0153] If the flash unit is connected in step S308, step S309, or step S310 and charging of the flash unit is OK, the camera control unit B advances the process to step S311.

[0154] In step S311, the camera control unit B performs an AE operation and determines exposure parameters assuming that the strobe 300 will emit light.

[0155] In step S312, the camera control unit B transmits information for pre-flash control to the strobe 300. The transmitted information includes the type of flash trigger, the flash method, the amount of flash light, and so on.

[0156] As will be described later, there are two types of light emission triggers: "SCLK synchronous light emission," in which the strobe emits light in synchronization with the assertion of SCLK_ST, and "XOUT synchronous light emission," in which the strobe emits light in synchronization with the assertion of SCLK_ST and XOUT.

[0157] There are two types of light emission methods: "flash emission," which causes the light-emitting part of the strobe to be turned on only once to emit a flash of light, and "flat emission," which controls the light-emitting part of the strobe to be turned on and off periodically to emit a predetermined amount of light at a predetermined time. When the light emission method is flat emission, the communication for pre-flash control includes information about the duration of light emission.

[0158] In step S313, the camera control unit B performs control via the adapter 200 to cause the flash to pre-emit light.

[0159] In the pre-flash, "SCLK synchronized flash flash" and "SCLK synchronized flat flash" are used.

[0160] After a predetermined time has elapsed, the camera 100 transmits command 4 for the adapter 200 using the serial communication signal 151 (T141). When the adapter 200 receives command 4 for the adapter 200, the adapter control unit 201 controls SCLK_ST to become VSTH.

[0161] In step S314, the camera control unit B acquires strobe information from the strobe 300 during and after the pre-flash.

[0162] In step S315, the camera control unit B calculates the amount of flash light to be emitted (amount of main flash light) during shooting based on the information obtained in the pre-flash processing in step S313 and step S314.

[0163] In step S316, the camera control unit B transmits information for main light emission control to the strobe 300. The transmitted information includes the light emission trigger type, light emission method, light emission amount, etc. If the light emission method is flat light emission, information regarding the light emission time is also included.

[0164] In step S317, the camera control unit B controls the main light emission of the strobe and the exposure operation of the image sensor 122 via the adapter 200.

[0165] For main light emission, "XOUT synchronized flash light emission" and "SCLK synchronized flat light emission" are used.

[0166] In step S318, the camera control unit B communicates with the strobe 300 to acquire the state after the main light emission, and then ends the process.

[0167] <Pre-flash (S313): SCLK synchronized flash (S313)> 13 is a diagram showing "SCLK synchronized flash emission." The camera 100 uses the serial communication signal 151 to send command 3 for the adapter 200 (T130). When the adapter 200 receives command 3 for the adapter 200, the adapter control unit 201 controls SCLK_ST to become 0V. When the strobe control unit 301 of the strobe 300 detects that SCLK_ST has become 0V, it controls the strobe emission unit 305 based on the information received in step S312 to emit a flash.

[0168] After a predetermined time has elapsed, the camera 100 transmits command 4 for the adapter 200 using the serial communication signal 151 (T131). When the adapter 200 receives command 4 for the adapter 200, the adapter control unit 201 controls SCLK_ST to become VSTH.

[0169] <Pre-flash: SCLK synchronized flash (S313)> 14 is a diagram showing "SCLK-synchronized flat light emission." The camera 100 uses the serial communication signal 151 to send command 3 for the adapter 200 (T140). When the adapter 200 receives command 3 for the adapter 200, the adapter control unit 201 controls SCLK_ST to become 0V. When the strobe control unit 301 of the strobe 300 detects that SCLK_ST has become 0V, it controls the strobe light emission unit 305 based on the information received in step S312 to perform flat light emission. After emitting light for a period of time based on the information received in step S312, the light emission stops.

[0170] <Main flash: XOUT synchronous flash (S317)> 15 is a diagram showing "XOUT synchronized flash emission." The camera 100 transmits command 3 for the adapter 200 using the serial communication signal 151 (T150). When the adapter 200 receives command 3 for the adapter 200, the adapter control unit 201 controls SCLK_ST to be 0V. Since the strobe 300 received the "XOUT synchronized flash emission" communication in step S316, it does not emit light at T150.

[0171] Next, the camera 100 asserts FNC1 (XON) (T151).

[0172] When XON is asserted, the adapter control unit 201 sets the signal XON_FET to high level, turns on the FET 206, and sets the signal XOUT to low level. When the signal XOUT goes low level, the transistor 309 of the strobe 300 turns on, and the signal / XOUT goes high level. When the strobe control unit 301 detects that the signal / XOUT is high level, it starts a flash emission operation.

[0173] When a predetermined time has elapsed since the assertion of XON, the camera control unit B negates FNC1(XON) (T152). When XON is negated, the adapter control unit 201 sets the signal XON_FET to low level, turns off the FET 206, and sets the signal XOUT to high level. When the signal XOUT becomes high level, the transistor 309 of the strobe 300 is turned off, and the signal / XOUT becomes low level. The predetermined time is determined based on the shutter speed set in the camera.

[0174] After a predetermined time has elapsed, the camera 100 transmits command 4 for the adapter 200 using the serial communication signal 151 (T153). When the adapter 200 receives command 4 for the adapter 200, the adapter control unit 201 controls SCLK_ST to become VSTH.

[0175] <Main light emission: SCLK synchronized flat light emission (S317)> 16 is a diagram showing "SCLK-synchronized flat emission" during main emission. The camera 100 transmits command 3 for the adapter 200 using the serial communication signal 151 (T160). When the adapter 200 receives command 3 for the adapter 200, the adapter control unit 201 controls SCLK_ST to be 0V.

[0176] In the strobe 300, when the strobe control unit 301 detects that SCLK_ST has become 0V, it controls the strobe light emitting unit 305 based on the information received in step S316 to perform flat light emission.

[0177] Next, the camera 100 asserts FNC1 (XON) depending on the open / close state of the shutter (T161). When XON is asserted, the adapter control unit 201 sets the signal XON_FET to high level, turns on the FET 206, and sets the signal XOUT to low level. When the signal XOUT goes low level, the transistor 309 of the strobe 300 is turned on, and the signal / XOUT goes high level.

[0178] When a predetermined time has elapsed since XON was asserted, the camera 100 negates FNC1(XON) (T162). When XON is negated, the adapter control unit 201 sets the signal XON_FET to low level, turns off the FET 206, and sets the signal XOUT to high level. When the signal XOUT becomes high level, the transistor 309 of the strobe 300 is turned off, and the signal / XOUT becomes low level.

[0179] The predetermined time is determined based on the shutter speed set in the camera.

[0180] Furthermore, the strobe 300 emits light for a period of time based on the information received in step S316, and then stops emitting light.

[0181] After a predetermined time has elapsed, the camera 100 transmits command 4 for the adapter 200 using the serial communication signal 151 (T164). When the adapter 200 receives command 4 for the adapter 200, the adapter control unit 201 controls SCLK_ST to become VSTH.

[0182] As described above, while XOUT is asserted, the strobe 300 emits light. This "SCLK synchronized flat emission" in the main emission is used for strobe photography when the shutter speed is high.

[0183] XOUT is a signal controlled in accordance with the open / close state of the shutter, and includes a period during which XOUT is asserted, during which the image sensor 122 exposes the subject image.

[0184] <Transmission of communication request from strobe> 17 and 18, the operation of notifying the camera 100 of a communication request from the strobe 300 via the adapter 200 will be described in detail.

[0185] FIG. 17 is a flowchart showing a process performed by the flash unit 300 when requesting communication with the camera 100.

[0186] In step S900, when the flash control unit 301 requests communication from the camera 100, it applies a predetermined voltage to the CCC terminal.

[0187] In steps S901 and S902, the flash control unit 301 turns off the application of a predetermined voltage to the CCC terminal after a predetermined time has elapsed.

[0188] The control flow chart in the adapter 200 at this time is shown in FIG.

[0189] In step S1000, when the CCC voltage is greater than a predetermined threshold CCC_V_TH and CCC_V becomes high level, in step S1001 the adapter control unit 201 asserts the / WAKE terminal.

[0190] The camera 100 initiates communication with the strobe control unit 301 by an interrupt operation using / WAKE. A timing chart of these operations is shown in FIG.

[0191] As described above, according to this embodiment, even if the configurations for notification and communication differ between the camera and the accessory, automatic flash control can be performed appropriately.

[0192] <Other embodiments> In this embodiment, the electronic device connected to the adapter 200 is described as a strobe, but it may be an electronic device other than a strobe, such as a GPS unit.

[0193] The present invention can also be realized by executing the following process. That is, software (programs) that realize the functions of the above-described embodiments are supplied to a system or device via a network or various storage media, and the computer (or CPU, MPU, etc.) of the system or device reads and executes the program codes. In this case, the programs and the storage media storing the programs constitute the present invention.

[0194] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0195] 101 Camera control unit A 102 Camera control unit B 201 Adapter control unit 301 Strobe control unit

Claims

1. An adapter device that is attached between an imaging device and an accessory device, a control means for controlling communication with the imaging device via the first contact, the second contact, and the third contact, and communication with the accessory device via the fourth contact and the fifth contact; the control means has a first communication mode for controlling transmission of data via the fourth contact in response to reception of data from the first contact or transmission of data via the second contact in response to reception of data via the fifth contact, and a second communication mode different from the first communication mode, in which, after receiving a second command and data via the first contact, the data is transmitted via the fourth contact; The adapter device is characterized in that the control means performs communication in the first communication mode in response to connection detection communication of the accessory device in the second communication mode and a first command corresponding to an instruction to transition to the first communication mode.

2. The adapter device described in claim 1, characterized in that the control means controls the connection detection communication so that a third notification is sent via the third contact in response to receiving a first notification via the fourth contact in response to receiving a second command via the first contact, and a second notification is sent via the fifth contact in response to receiving a first notification via the fourth contact in response to receiving a second command via the first contact.

3. 3. The adapter device according to claim 2, wherein the control means performs the first notification by changing the signal level of the fourth contact from a first signal level to a second signal level that is higher than the first signal level.

4. The adapter device according to claim 2 or 3, characterized in that the second notification is made by the fifth contact changing the signal level from the third signal level to a fourth signal level that is higher than the third signal level.

5. The adapter device according to any one of claims 2 to 4, characterized in that the control means performs the third notification by changing the signal level of the third contact from a fifth signal level to a sixth signal level that is higher than the fifth signal level.

6. 6. The adapter device according to claim 1, wherein the control means communicates data communicated via the first contact and the fifth contact in synchronization with a clock signal received via a sixth terminal.

7. 7. The adapter device according to claim 1, wherein the first communication mode is a mode in which a voltage level of data received via the first contact is changed and transmitted via the fourth contact.

8. An imaging device to which an accessory device can be attached via an adapter device, a control means for controlling communication with the adapter device via the first contact, the second contact and the third contact; the control means has a first communication mode for controlling communication with the accessory device via the adapter device via the first contact and the second contact, and a second communication mode different from the first communication mode, and in the second communication mode, transmits a second command and data via the first contact; The control means performs communication in the first communication mode in response to connection detection communication of the accessory device in the second communication mode and transmission of a first command corresponding to an instruction to transition to the first communication mode.

9. 9. The imaging device according to claim 8, wherein the control unit receives a third notification via the third contact in response to transmission of a second command via the first contact during the connection detection communication.

10. The imaging device according to claim 9, wherein the control means receives the third notification by changing the signal level of the third contact from a fifth signal level to a sixth signal level that is higher than the fifth signal level.

11. 11. An adapter device according to claim 8, wherein the control means communicates data communicated via the first contact and the fifth communication contact in synchronization with a clock signal transmitted via a sixth terminal.

12. A method for controlling an adapter device attached between an imaging device and an accessory device, comprising: a control step of controlling communication with the imaging device via a first contact, a second contact, and a third contact, and communication with the accessory device via a fourth contact and a fifth contact; In the control step, a communication in a first communication mode is executed, in which the transmission of data via the fourth contact in response to reception of data from the first contact or the transmission of data via the second contact in response to reception of data via the fifth contact is controlled, and a communication in a second communication mode different from the first communication mode is executed, in which, in the second communication mode, after a second command and data are received via the first contact, the data are transmitted via the fourth contact; A control method for an adapter device, characterized in that in the control step, communication in the first communication mode is performed in response to connection detection communication of the accessory device in the second communication mode and a first command corresponding to an instruction to transition to the first communication mode.

13. A control method for an imaging device to which an accessory device can be attached via an adapter device, comprising: a control step of controlling communication with the adapter device via the first contact, the second contact, and the third contact; In the control step, a communication in a first communication mode that controls communication with the accessory device via the adapter device and a communication in a second communication mode different from the first communication mode are executed via the first contact and the second contact, and in the second communication mode, a second command and data are transmitted via the first contact; a control method for an imaging device, characterized in that in the control step, communication in the first communication mode is performed in response to connection detection communication of the accessory device in the second communication mode and transmission of a first command corresponding to an instruction to transition to the first communication mode.

Images