JP2005173165A - Camera system having radiocommunication between camera and accessory - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera system where an accessory is surely controlled by a camera at high speed, to provide the camera and the accessory constituting the camera system, and to provide an accessory control method by the camera. <P>SOLUTION: In the camera system provided with the camera having a 1st radiocommunication means, and the accessory which is exchangeably attached to the camera, and having a 2nd radiocommunication means for communicating with the 1st radiocommunication means, regarding the method for controlling the accessory by the camera, the accessory comprises a step of judging whether the accessory is attached to the camera, and a step of making the 2nd radiocommunication means in an active state when it is judged that the accessory is attached to the camera, and radio-receiving radiocommunication identification information from the camera, and also, radio-transmitting the identification information and accessory information to the camera. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention generally relates to a camera system including a camera body, a replaceable lens device, and a replaceable flash device (i.e., an accessory), and more particularly to communication between a camera and an accessory.

  Conventionally, a camera that consists of a camera and accessories, and that controls exposure of the camera based on various types of shooting information, such as shutter speed control value, aperture control value, film sensitivity (ISO), and photometric value from the photometric sensor output in the camera The system is already known (see, for example, Patent Documents 1 and 2). This camera system transmits control information related to exposure from the camera to the accessory to perform various controls of the accessory. With the widespread use of the camera system, there is an increasing demand for such control at high speed and reliably.

Communication between the camera and the accessory is serial communication using a sliding-type electrical signal contact. A sliding contact has a spring mechanism on one of the camera and accessory and applies a predetermined pressing force to the other contact. Form. The serial communication interface determines the communication speed and allowable voltage range, and transmits information by maintaining a certain level of compatibility. In serial communication, data is generally set in synchronization with the falling edge of the serial clock, and data is fetched in synchronization with the rising edge.
JP 2003-228113 A JP 2003-186097 A

  However, in the conventional camera system, the rising and falling of the serial clock and the rising and falling waveforms of the serial data are deformed due to the contact resistance between the contacts and the capacitance between the wires, and the serial communication speed is made faster than a predetermined value. As a result, the synchronization between the serial clock and the serial data is out of sync and normal data transmission cannot be performed. For this reason, the conventional camera system cannot increase the serial communication speed to a predetermined value or higher, and does not necessarily satisfy the request that the camera controls the accessory at high speed and reliably.

  Accordingly, an object of the present invention is to provide a camera system in which an accessory controls an accessory at high speed and with certainty, a camera and an accessory constituting the camera system, and an accessory control method using the camera.

  A control method according to one aspect of the present invention includes a camera having a first wireless communication unit and a second wireless communication unit that is exchangeably attached to the camera and capable of communicating with the first wireless communication unit. In a camera system having an accessory, the camera controls the accessory, wherein the accessory determines whether the accessory is attached to the camera, and the accessory is connected to the camera. When it is determined that it is attached, the second wireless communication means is enabled to wirelessly receive wireless communication identification information from the camera, and wirelessly transmit the identification information and accessory information to the camera. And a step.

  According to another aspect of the present invention, there is provided a control method comprising: a camera having a first wireless communication unit; and a second wireless communication unit that is exchangeably attached to the camera and capable of communicating with the first wireless communication unit. In the camera system having an accessory, the camera controls the accessory, wherein the camera operates a detection unit that detects whether the accessory is attached to the camera and the first wireless communication unit. Enabling the camera, the camera wirelessly transmitting identification information for wireless communication to the accessory, and the camera authenticating the identification information received from the accessory. .

  The accessory may be a flash device, and may hold the identification information even if it is separated from the camera.

  A camera system according to another aspect of the present invention is a camera system including a camera and an accessory that is replaceably attached to the camera, and the camera communicates information for controlling the accessory. The first wireless communication means and an authentication means for authenticating the accessory, wherein the accessory has a second wireless communication means capable of communicating with the first wireless communication means. .

  The camera further comprises detection means for detecting whether or not the accessory is attached to the camera, and means for enabling the detection means and the first wireless communication means, The apparatus may further include means for determining whether an accessory is attached to the camera and means for enabling the second wireless communication means. The detection means may be composed of a semiconductor element. The accessory is, for example, a lens device or a flash device. The accessory may be a flash device and may include a memory that holds identification information used for wireless communication with the camera.

  A camera according to another aspect of the present invention is a camera in which an accessory is replaceably mounted and constitutes a camera system together with the accessory, and wireless communication means for wirelessly communicating information for controlling the accessory And an authentication means for authenticating the accessory, a detection means for detecting whether the accessory is attached to the camera, and a means for enabling the detection means and the wireless communication means. .

  An accessory according to another aspect of the present invention is an accessory that is exchangeably attached to a camera and that constitutes a camera system together with the camera, and wirelessly communicates information for controlling the accessory with the camera. It has a communication means, a detection means for detecting whether or not the accessory is attached to the camera, and a means for enabling the wireless communication means.

  Further objects and other features of the present invention will become apparent from the preferred embodiments described below with reference to the accompanying drawings.

  ADVANTAGE OF THE INVENTION According to this invention, the camera system which a camera controls an accessory at high speed reliably can be provided, the camera and accessory which comprise it, and the control method of the accessory by a camera.

  Hereinafter, a camera system 1 as an embodiment of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a schematic block diagram of the camera system 1. The camera system 1 is an example system applied to a single-lens reflex camera, and includes a camera 10, a lens device 20, and a flash device 30.

  The camera 10 is connected to a camera microcomputer (CPU) 11 that controls the camera 10, a DC / DC converter 12 that supplies power to the CPU 11, a battery 13 that is a power source of the camera 10, and the CPU 11, and measures the luminance of the subject. It has a side light sensor 14 and a wireless communication interface (IF) 15 for performing wireless communication with the accessory.

  Reference numeral 16 denotes a semiconductor switch which is a mounting detection, which is connected to the lens device 20 and has a function of transmitting the presence / absence of a control signal from the CPU 11 to the lens device 20. Reference numeral 17 denotes a semiconductor switch for detecting attachment, which is connected to the flash device 30 and has a function of transmitting the presence or absence of a control signal from the CPU 11 to the flash device 30.

  The CPU 11 enables and disables the wireless communication interface 15 and the semiconductor switches 16 and 17. If the CPU 11 is “H”, the semiconductor switches 16 and 17 are turned on, and the wireless communication interface 15 can wirelessly communicate with an accessory corresponding to the turned on semiconductor switch. On the contrary, if the CPU 11 is “L”, the semiconductor switch 16 is turned off, and the wireless communication interface 15 cannot wirelessly communicate with an accessory corresponding to the semiconductor switch that is turned off.

  The lens device 20 is detachably attached to the camera 10 and includes a photographing lens that can be driven to an arbitrary aperture amount, and includes a control unit 21, an aperture 22, a battery 23 that is a power source of the lens device 20, and a wireless communication interface 15. And a wireless communication interface 25 capable of wireless communication.

  The flash device 30 is detachably attached to the camera 10 and also functions as a remote control type flash device. The flash device 30 generates a high voltage for flash emission, a control unit 31, a light emitting unit 32 connected to the control unit 31, A booster circuit 33 that supplies power to the light emitting unit 32, a battery 34 that is a power source of the flash device 30, a wireless communication interface 35 that can wirelessly communicate with the wireless communication interface 15, and a memory 36 that stores a wireless ID described later.

  FIG. 2 is a timing chart for explaining the operation of the camera system 1, and FIG. 2B is an enlarged view of a portion A in FIG. In FIG. 2, the master is the camera 10, and the slave is the lens device 20 or the flash device 30. The master sets the detection switch 16 or 17 to “H” when starting wireless communication. When the slave side detects that the detection switch is turned on, it permits the wireless communication interface and enters a reception standby state. Subsequently, the master side transmits the first command after a predetermined time Tr has elapsed. Assume that the transmission interval between commands and data is opened at a predetermined time Td. Subsequently, after transmitting a predetermined amount of transmission data, the master hands over the transmission right of wireless communication to the slave, and the slave side starts transmission. If the slave side does not transmit until the predetermined time Tf elapses after the master side completes transmission, the slave is not installed, or the slave side cannot transmit wireless data due to some trouble, or the slave detection switch is incorrect It is determined that an operation has been performed, an abnormality is detected, and wireless communication is terminated. Further, even when the communication ID returned from the slave side is wrong with respect to the communication ID transmitted from the master side, the abnormality is similarly detected and the wireless communication is terminated.

  FIG. 3 is a flowchart showing the operation of the camera system 1. In FIG. 3, first, the CPU 11 performs initial setting of data necessary for camera control, such as a shooting mode and ISO sensitivity (step 101).

  Next, the process proceeds to communication with the lens device 20 (step 200). FIG. 4 shows a detailed flow of communication 200 with the lens apparatus 20. Referring to FIG. 4, first, the CPU 11 enables the semiconductor switch 16 to be set to “H” and enables the wireless communication interface 15, and provides identification information (ID) for wireless communication after a predetermined time has passed, to the lens device 20. (Step 201). If the lens device 20 is attached to the camera 10, the process proceeds to step 202. If the lens device 20 is not attached, the wireless ID is discarded (step 207), and the communication with the lens device 20 is terminated.

  In step 202, the control unit 21 detects that the communication is possible by confirming that the semiconductor switch 16 is attached to the camera 10 from the H state. At this time, the control unit 21 enables the wireless communication interface 25 to receive the wireless ID from the camera 10 after a lapse of a predetermined time, and transmit the wireless ID and information on the lens device 20 to the camera 10. In response to this, the camera 10 receives the wireless ID of the lens device 20 and the information of the lens device 20.

  Next, the CPU 11 determines whether or not the wireless IDs match (step 203). If the wireless IDs do not match, the CPU 11 determines that an abnormality has occurred in communication (step 206). End communication. On the other hand, if the CPU 11 determines that the wireless IDs match (step 203), the CPU 11 determines that the wireless communication has been completed normally and disables the wireless communication interface 15 (step 204). Further, the CPU 11 sets the semiconductor switch 16 to “L” (off) to disable the operation (step 205), whereby communication with the lens device 20 and detection of connection are not performed until the next permission is given. Thereafter, the process proceeds to step 207 and the communication with the lens device 20 is terminated.

  When the camera 10 communicates with the lens apparatus 20, the operation from step 201 to step 207 is repeated as a series of operations.

  Next, the process proceeds to communication with the flash device 30 (step 300). FIG. 5 shows a detailed flow of the flash communication 300 shown in FIG. Referring to FIG. 5, first, the CPU 11 enables the semiconductor switch 17 to be set to “H” and enables the wireless communication interface 15, and sends identification information (ID) for wireless communication to the flash device 30 after a predetermined time has elapsed. (Step 301). If the flash device 30 is attached to the camera 10, the process proceeds to step 302. If the flash device 30 is not attached, the wireless ID is discarded (step 307) and the communication with the flash device 30 is terminated.

  In step 202, the control unit 21 detects that the communication is possible by confirming that the semiconductor switch 16 is attached to the camera 10 from the H state. At this time, the control unit 21 enables the wireless communication interface 25 to receive the wireless ID from the camera 10 after a predetermined time has passed, and to the camera 10 the wireless ID and flash ID, the light emission mode setting state, the zoom position setting state, Various information unique to the flash, such as the state of charge of the main capacitor shown, is transmitted to the camera 10. In response to this, the camera 10 receives the wireless ID of the flash device 30 and the information of the flash device 30.

  Next, the CPU 11 determines whether or not the wireless IDs match (step 303). If the wireless IDs do not match, the CPU 11 determines that an abnormality has occurred in the communication (step 306), and proceeds to step 307. End communication. On the other hand, if the CPU 11 determines that the wireless IDs match (step 303), the CPU 11 determines that the wireless communication has been completed normally and disables the wireless communication interface 15 (step 304). In addition, the CPU 11 sets the semiconductor switch 17 to “L” (off) to disable the operation (step 305), whereby communication with the flash device 20 and detection of connection are not performed until the next permission is given. Thereafter, the process proceeds to step 307 to end the flash communication.

  When the camera 10 communicates with the flash unit 30, the camera 10 repeatedly performs the operations from step 301 to step 307 as described above.

  Returning again to FIG. 3, the photometric sensor 14 is driven to perform photometry of the object scene, obtain a photometric value Bv, and perform side light 10 ms (step 102). Next, the CPU 11 performs an exposure value calculation for calculating a shutter speed Tv and a shooting lens aperture Av necessary for exposure control from the camera control data such as the shooting mode and ISO sensitivity given in the initial settings and the photometric value Bv. Perform (step 103). Next, the CPU 11 performs photometry again with the photometry sensor 14 immediately before the preliminary light emission, and measures the steady light amount of the object scene (step 104).

  Next, the CPU 11 performs flash communication (step 300), and starts preliminary light emission of the flash device 30 (step 105). The preliminary light emission time (Tpre) and the light emission intensity (Lpre) are controlled by numerical values set in advance. Next, the CPU 11 performs photometry with the photometric sensor 14 during preliminary light emission of the flash device 30, and measures the reflected light amount and the steady light amount of the flash light irradiated to the object scene by the flash device 30 (step 106).

  Next, the CPU 11 calculates the optimum amount of main light emission based on the photometric results of steps 104 and 106 (step 107). That is, the contribution due to the preliminary light emission is obtained from the difference between the photometry A (step 104) and the photometry B (step 106), and the main emission light amount Lmain is obtained based on the exposure control data (shutter speed Tv, photographing lens aperture Av, photometric value Bv). Is calculated. Next, the CPU 11 performs flash communication (step 300), and instructs the flash device 30 about the main light emission amount Lmain (step 108).

  Next, the CPU 11 performs lens communication (step 200), and sends aperture control data Av to the photographing lens (step 109). Subsequently, the control unit 21 starts driving the diaphragm 22 and drives the diaphragm 22 of the photographing lens to the diaphragm amount (Av value) calculated in Step 103. After a lapse of a predetermined time from the start of driving the diaphragm 22 until it stabilizes, the CPU 11 drives a main mirror (not shown) to retract from the optical axis (step 110). Next, the CPU 11 drives a shutter circuit (not shown) and causes the shutter front curtain and the rear curtain to run so as to control the desired shutter time (step 111).

  Next, when the shutter front curtain completes traveling, a shutter front curtain travel completion signal (not shown) is activated and transmitted to the flash unit 30 via the connection terminal X of the camera 10 and the flash unit 30 (step 112). The flash device 30 starts the main light emission at the same time as detecting that the shutter front curtain travel completion signal has been activated via the connection terminal X. The booster circuit 33 of the flash device 30 performs voltage control so that a main capacitor (not shown) reaches a predetermined voltage, and the light emission control unit 31 of the flash device 30 distributes energy stored in the main capacitor to emit light. The light amount is controlled so that the light emission time becomes a predetermined amount.

  Next, the main mirror and shutter are returned to the initial state (step 113), lens communication (step 200) is performed to return the lens aperture to the initial state (step 114), and the camera exposure control sequence is terminated.

  The above is a series of operations related to the exposure control sequence of the camera. Thus, in this embodiment, since the wireless communication means is used instead of the communication interface via the electrical signal contact, the communication speed can be made fast and reliable. Further, even when a plurality of lens devices are within the communication area, accessories that can communicate with the camera are always paired because wear determination and wireless ID authentication are used.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various change and deformation | transformation are possible within the range of the summary. For example, even if the flash device 30 is removed from the camera 10, the memory 36 may retain the wireless ID. As a result, it is possible to deal with a remote control type flash device. Therefore, the present invention does not necessarily require the mounting of the camera and accessories.

It is a schematic block diagram of the camera system of one embodiment of the present invention. 2 is a timing chart for explaining the operation of the camera system shown in FIG. 1. It is a flowchart which shows operation | movement of the camera system shown in FIG. It is a detailed flowchart of the lens communication shown in FIG. 4 is a detailed flowchart of flash communication shown in FIG. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera system 10 Camera 20 Lens apparatus 30 Flash apparatus 11, 21, 31 Control part 15, 25, 35 Wireless communication interface 16, 17 Semiconductor switch

Claims (10)

In a camera system comprising: a camera having first wireless communication means; and an accessory having second wireless communication means that is exchangeably attached to the camera and capable of communicating with the first wireless communication means. A method of controlling an accessory,
Determining whether the accessory is attached to the camera;
When the accessory determines that the accessory is attached to the camera, the accessory enables the second wireless communication means to wirelessly receive identification information for wireless communication from the camera, and the identification information and the Wirelessly transmitting accessory information to the camera. In a camera system comprising: a camera having first wireless communication means; and an accessory having second wireless communication means that is exchangeably attached to the camera and capable of communicating with the first wireless communication means. A method of controlling an accessory,
The camera is operable to enable detection means for detecting whether the accessory is attached to the camera and the first wireless communication means;
The camera wirelessly transmitting identification information for wireless communication to the accessory;
Authenticating the identification information received from the accessory.   3. The method according to claim 1, wherein the accessory is a flash device and retains the identification information even when separated from the camera. A camera system having a camera and an accessory that is exchangeably attached to the camera,
The camera
First wireless communication means for communicating information for controlling the accessory;
Authentication means for authenticating the accessory,
The accessory has a second wireless communication unit capable of communicating with the first wireless communication unit. The camera has detection means for detecting whether the accessory is attached to the camera;
Means for enabling the detection means and the first wireless communication means to operate;
The accessories are
Means for determining whether the accessory is attached to the camera;
5. The camera system according to claim 4, further comprising means for enabling the second wireless communication means.   6. The camera system according to claim 5, wherein the detecting means is made of a semiconductor element.   The camera system according to claim 4, wherein the accessory is a lens device or a flash device.   The camera system according to claim 4, wherein the accessory is a flash device, and has a memory that holds identification information used for wireless communication with the camera. An accessory is mounted so as to be replaceable, and constitutes a camera system together with the accessory,
Wireless communication means for wirelessly communicating information for controlling the accessory;
Authentication means for authenticating the accessory;
Detecting means for detecting whether the accessory is attached to the camera;
A camera comprising means for enabling the detection means and the wireless communication means to operate. An accessory that is replaceably attached to a camera and that forms a camera system together with the camera,
Wireless communication means for wirelessly communicating information for controlling the accessory with the camera;
Means for determining whether the accessory is attached to the camera;
Means for enabling the wireless communication means to operate.