JP2005173266A - Camera accessory and camera system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve operability by always securing a power supply state to a control system, preventing volatile data in the control system from disappearing and preventing the start time of a camera accessory from being delayed. <P>SOLUTION: The camera accessory (10) attached to a camera comprises driving systems (102, 103) for receiving power supply and driving operation parts in the camera accessory (10), a control system (101) for receiving power supply and controlling the camera accessory (10), a power supply means (104) for receiving first power supply from the camera and supplying operation power to the driving systems (102, 103) and the control system (101), and an accessory power supply (106) for supplying second power only to the control system (101) when the first power supply from the camera is stopped. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a camera accessory such as an interchangeable lens and a strobe that is detachably attached to a single-lens reflex camera or a video camera, and a camera system including the camera accessory and the camera.

  Usually, in a camera system that consists of a camera and an interchangeable lens that is detachably attached to the camera, and that can communicate between the camera and the interchangeable lens, the camera is equipped with a battery that serves as a power source, and the interchangeable lens is changed from the battery in the camera. Is configured to supply desired power. The power supply at this time is provided via a connection terminal provided in each of the mount unit that is provided in each of the camera and the interchangeable lens and coupled to each other.

  However, in the case of such contact type power supply, by repeatedly attaching and detaching the interchangeable lens to and from the camera, the surface of the connection terminal is worn and the contact resistance increases. Thereby, there is a possibility that the transmission efficiency of power is deteriorated and a desired power supply cannot be performed. In addition, when the camera system is used outdoors, the contact portion of the connection terminal is short-circuited due to condensation or rain, and an overcurrent flows in the circuits in the camera and the interchangeable lens, which may cause equipment failure.

  Here, as a means for solving the above-described problem of power transmission due to poor contact, a camera that supplies power in a contactless manner using the principle of electromagnetic induction has been proposed (for example, see Patent Document 1). Specifically, an electromotive force due to electromagnetic induction is generated in the secondary side coil provided in the interchangeable lens by energizing the primary side coil provided in the camera, and this electromotive force is stored in the storage means to operate the interchangeable lens. Power is used.

  On the other hand, a conventional contact-type power supply camera has a control system power supply means for supplying power to a control system such as a microcomputer provided in the interchangeable lens, and a motor provided in the interchangeable lens. Some have two power supply lines of power supply means for drive system that supplies power to the drive system.

This is because power supply to the control system must always be performed in order to retain data in the RAM, detect switch operation, etc., but power supply to the drive system only needs to be performed when the drive system is driven. is there. In other words, by using the two power supply means properly, it is possible to obtain the effects of user convenience and power saving.
JP-A-9-90462 (paragraph numbers 0075 to 0077, FIG. 10)

  In the case of the non-contact type power supply described above, power loss is larger than that of the contact type. Therefore, it is desirable to stop the power supply when power supply is not required. However, if the power supply to the interchangeable lens is frequently stopped, it is not possible to detect that the user has operated the lens in the interchangeable lens due to power shortage, or the microcomputer or control IC in the interchangeable lens is volatilized. Characteristic data is lost, and the initialization operation and start-up of the interchangeable lens take time due to the delay of power feeding.

  In addition, in a camera that supplies power in a contactless manner, providing two power supply systems, that is, a control system power supply means and a drive system power supply means, increases the cost, and further efficiently supplies power. Will not be able to. For this reason, the power supply means which suppressed the power loss at the time of electric power feeding is maintained, maintaining a user's usability.

  The present invention is a camera accessory mounted on a camera, and includes a drive system that receives power supply to drive an operation unit in the camera accessory, a control system that receives power supply and controls the camera accessory, and a camera system. Power supply means for receiving the power of 1 and supplying operating power to the drive system and the control system. When the supply of the first power from the camera is stopped, the second power is supplied only to the control system. And an accessory power supply for supplying power.

  In addition, the camera system of the present invention can be configured by the camera accessory described above and a camera to which the camera accessory is attached and supplies the first power to the camera accessory.

  According to the present invention, even when the supply of the first power from the camera is stopped, the control system can be always operated by supplying the second power from the accessory power source to the control system. it can. As a result, for example, it is possible to prevent volatile data in the control system from being lost or the start-up time of the camera accessory from being delayed, thereby improving the usability of the user. In addition, according to the present invention, only the accessory power source is provided in the camera accessory, and the camera accessory can be reduced in size and cost as compared with the case where a plurality of power supply lines are provided as in the related art.

  By making 2nd electric power lower than said 1st electric power, the electric capacity of the accessory power supply which supplies this 2nd electric power can be made small.

  If the power supply means receives the first power supply from the camera in a contactless system, contact resistance due to friction between the contact terminals and contact part short circuit due to the external environment are reduced compared to the contact system. Can be prevented.

  The control system has communication means for performing communication with the camera, and the control system performs first communication with the camera via the communication means when the state of the camera accessory changes after the supply of the first power is stopped. It is possible to transmit a signal for requesting the start of power supply. In this way, power can be saved by supplying or not supplying the first power according to the state of the camera accessory.

  A communication unit that communicates with the camera, and the accessory power source is a primary battery. When the remaining battery level of the accessory power source falls below a predetermined level, the control system communicates with the camera via the communication unit. On the other hand, a signal indicating that the remaining battery level has decreased can be transmitted. Thus, for example, if the user is notified that the battery level has dropped on the camera side, the user can be urged to replace the accessory power source, and the remaining amount of accessory power source will be completely eliminated. Can be prevented, and loss of volatile data can be prevented in the control system that receives power from the accessory power supply.

  When there is a communication means for performing communication with the camera and the accessory power source is a secondary battery, the remaining battery level of the accessory power source becomes lower than a predetermined level after the supply of the first power is stopped. Sometimes, the control system can transmit a signal requesting the camera to start supplying the first power via the communication means. Thereby, for example, the camera can supply the first power to the camera accessory in response to a signal requesting the start of the supply of the first power, and the camera accessory receives the supply of the first power. Can work.

  By using the secondary power source as the accessory power source and charging the accessory power source using the first power, it is not necessary to replace the battery every time the remaining charge level is exhausted, and the usability for the user can be improved.

  Examples of the present invention will be described below.

  A camera system that is Embodiment 1 of the present invention will be described. The camera system of the present embodiment includes a camera and an interchangeable lens (camera accessory) that is detachably attached to the camera. This camera system supplies contactless power using electromagnetic induction from a camera to an interchangeable lens, as will be described later, and uses a light emitting diode and a photodiode for data communication between the camera and the interchangeable lens. It is performed by optical communication.

  FIG. 1 is a block diagram showing a circuit configuration in the camera system of the present embodiment. Here, the thin line represents the signal line, and the thick line represents the power supply line.

  In FIG. 1, a lens microcomputer 101 that controls the operation of the interchangeable lens 10 communicates data with the camera microcomputer 111 in the camera 20 via communication light emitting diodes 109b and 109d and photodiodes 109c and 109e (communication means). It can be performed. Here, the light emitting diode 109b and the photodiode 109c are used for communication from the camera 20 side to the interchangeable lens 10 side, as indicated by the arrows in FIG. 1, and the light emitting diode 109d and the photodiode 109e are exchanged. It is used for communication from the lens 10 side to the camera 20 side.

  The lens microcomputer 101 controls the driving of the photographing lens by outputting a control signal to a lens driving system (including a photographing lens (not shown) and a driving unit that drives the photographing lens) 102. That is, in the lens driving system 102, zooming is performed by moving a zooming lens in the photographic lens in the optical axis direction in accordance with a command value from the lens microcomputer 101, and a focus adjusting lens in the photographic lens. Focusing is performed by moving the lens in the optical axis direction.

  In addition, the lens microcomputer 101 outputs a control signal to an aperture driving system (including an aperture (not shown) and a driving unit that drives the aperture) 103 to change the aperture diameter, so that the amount of light incident on the image plane Adjust. That is, in the aperture driving system 103, an operation of reducing the aperture to a set position or returning to the open state is performed according to a command value from the lens microcomputer 101.

  Further, the lens microcomputer 101 displays the state of the interchangeable lens 10 (zoom position, focus position, aperture value state, etc.) and information about the interchangeable lens 10 (open aperture value, focal length, data necessary for focus adjustment, etc.) The data is transmitted from the communication light emitting diode 109d to the camera 20 via the interface 107.

  In the interchangeable lens 10, the voltage value required for driving the driving unit (actuator) in the lens driving system 102 and the aperture driving system 103 is different from the voltage value required in the control system such as the lens microcomputer 101. That is, the voltage value related to the control system is lower than the voltage value related to the drive system. For this reason, the voltage dividing unit 104 divides the power supply voltage supplied from the camera 20 and supplies an appropriate voltage to the drive system and the control system.

  The primary battery 106 is connected to the lens microcomputer 101 and a control IC (not shown). As will be described later, when the power supply from the camera 20 side to the interchangeable lens 10 side is interrupted, the lens microcomputer 101 and the like can operate by receiving the power supply from the primary battery 106.

  The remaining amount detection unit 105 always detects the remaining amount of the primary battery 106, for example, the voltage value, and outputs the detection result to the lens microcomputer 101.

  In the camera 20, a focus detection unit 114 for detecting the focus adjustment state of the photographing optical system, a photometry unit 115 for measuring the luminance of the subject, and a shutter unit 116 for driving a light shielding member capable of opening and closing the light passage opening. A display unit 117 that displays specific information (for example, a captured image and shooting conditions) and a control unit 118 that controls driving of components (for example, a sounding body and a display lamp described later) provided in the camera 20 are provided. These operations are controlled by the camera microcomputer 111.

  Here, the camera microcomputer 111 receives a signal input from the SW1 (119) which is turned on when a release button (not shown) provided in the camera 20 is half-pressed, and performs a shooting preparation operation (photometry operation or focus detection). Operation). At this time, the camera microcomputer 111 calculates an exposure value (shutter speed or aperture value) based on the result of the photometric operation.

  In addition, the camera microcomputer 111 receives a signal input from the SW2 (120) which is turned on when the release button is fully pressed, and performs a shooting operation (film exposure or recording of image data captured by the image sensor). Recording on a medium). SWM (121) is a switch for switching the shooting mode, and the camera microcomputer 111 can set the shooting mode according to the input signal from the SWM.

  The electric elements in the camera 20 such as the camera microcomputer 111 described above can operate by receiving power supply from the battery 113 provided in the camera 20.

  The voltage adjustment unit 112 can switch on / off the power supply to the electric system in the interchangeable lens 10 based on a control signal from the camera microcomputer 111. That is, the voltage adjustment unit 112 supplies power to the coil 109a in the interchangeable lens 10 based on a control signal from the camera microcomputer 111, or cuts off this power supply.

  If the coil 109a on the camera 20 side is energized, an electromotive force is generated in the coil 109a ′ on the interchangeable lens 10 side by the action of electromagnetic induction (non-contact type), and this electromotive force is exchanged via the voltage dividing unit 104. This is supplied to the electrical system in the lens 10. Further, if the energization to the coil 109a on the camera 20 side is cut off, no electromotive force is generated in the coil 109a ′ on the interchangeable lens 10 side, and power supply to the electrical system in the interchangeable lens 10 is not performed. .

  For example, if the user does not operate the camera 20 or the interchangeable lens 10 within a predetermined time, the camera microcomputer 111 determines that the interchangeable lens 10 does not need to be operated, and the interchangeable lens is used for power saving. The power supply to the electric system in 10 can be stopped.

  In the camera system of the present embodiment, the power supply from the camera 20 to the interchangeable lens 10 is performed by the non-contact method using the coils 109a and 109a 'as described above, and one power supply line is provided. For this reason, it is possible to reduce the size and cost of the camera system and to reduce power loss as compared with the case where a plurality of contactless power supply lines are provided as in the prior art.

  Further, the power supply to the control system (lens microcomputer, etc.) of the interchangeable lens 10 uses the power from the camera 20, and when the power supply from the camera 20 is cut off, the power from the primary battery 106 is used. Used. For this reason, electric power is constantly supplied to the control system of the interchangeable lens 10, and it is possible to prevent volatile data in the control system from being lost or starting from being delayed. In addition, in this embodiment, since the primary battery 106 is only provided in the interchangeable lens 10, the camera system can be downsized and compared with the case where two power supply lines are provided between the camera and the interchangeable lens as in the prior art. Cost reduction can be achieved.

  Next, the configuration of various detection units and switches provided in the interchangeable lens 10 will be described with reference to FIG. Here, the lens microcomputer 101 detects a signal from each detection unit or switch by an interrupt process, and performs a control operation according to the detection result.

  The focus detection unit 202 detects a change in movement of the focus lens in the photographing optical system (in the manual setting, whether or not the focus ring has been operated), and outputs the detection result to the lens microcomputer 101. The output of the detection unit 202 includes an output of a detection circuit composed of a brush and a gray code pattern and an output of an encoder.

  The zoom detection unit 203 detects a change in movement of the zoom lens of the photographing optical system (whether or not the zoom ring has been operated in the manual setting), and outputs the detection result to the lens microcomputer 101.

  The AF / MFSW 204 is a switch for switching between auto focus and manual focus. The lens microcomputer 101 drives the focus lens (manual focus) based on the operation of a focus ring (not shown) provided in the interchangeable lens 10 according to the output of the AF / MFSW 204, or at the focus detection unit 114. It is selected whether to drive the focus lens (autofocus) based on the detection result.

  The focus preset SW 205 and the focus preset playback SW 206 are switches for using the focus preset function. That is, when the focus preset SW 205 is turned on by a user operation, the lens microcomputer 101 stores in the memory 101 a in the lens microcomputer 101 the position of the focus lens that is in focus with respect to a specific subject (specific subject distance). Remember. Further, when the focus preset reproduction SW 206 is turned on by a user operation, the lens microcomputer 101 reads the position of the focus lens stored in the memory 101a and controls the lens driving system 102 to control the focus lens. Move to the reading position.

  The AF start / stop SW 207 is a switch for instructing the camera 20 to start and stop autofocus from the interchangeable lens 10 when the autofocus mode is selected by operating the AF / MFSW 204.

  The soft focus correction drive SW 208 is a switch for changing the degree of blur of the subject image by driving the soft focus lens of the photographic lens, and corrects the shift of the focus position caused by the movement of the soft focus lens. It is also a switch for.

  The lens microcomputer 101 determines a change in the state of the interchangeable lens based on the outputs of the detection units 202 and 203 as necessary, or determines a change in the state of the interchangeable lens by interrupt processing. Here, when it is determined that the power supply from the camera 20 to the interchangeable lens 10 is cut off (one of the change in the state of the interchangeable lens), the camera 20 (photodiode 109e) is connected via the light emitting diode 109d. Data relating to a power supply request is transmitted to the terminal.

  FIG. 3 is a flowchart showing the operation of the lens microcomputer 101, and mainly shows the operation flow when the power supply from the camera 20 is cut off.

  In step S301, the lens microcomputer 101 determines whether or not the power supply from the camera 20 side is cut off, that is, whether or not the power supply from the voltage dividing unit 104 is performed. Here, if the power supply is not interrupted, the process is terminated. On the other hand, if the power supply is interrupted, the process proceeds to step S302.

  In step S302, data to be stored in advance is stored in a register. In step S303, the lens microcomputer 101 shifts to a sleep state for power saving and ends the process.

  FIG. 4 shows a state in which the power supply to the interchangeable lens 10 is cut off, the switch 20 provided in the interchangeable lens 10 is operated, and data relating to a power supply request is transmitted to the camera 20. It is a flowchart which shows the operation | movement according to said switch operated after receiving supply. In this embodiment, the switch state of the interchangeable lens 10 (the state of the interchangeable lens 10) is detected by the interrupt processing of the lens microcomputer 101.

  In step S401, the lens microcomputer 101 in the sleep state cancels the sleep state (power saving mode) by an interrupt operation and returns to the normal mode.

  In step S402, data relating to a power supply request is transmitted to the camera 10 (photodiode 109e) via the light emitting diode 109d.

  In step S403, it is determined whether power is being supplied from the camera 20 side. If the voltage value input to the lens microcomputer 101 is greater than or equal to the predetermined value, it is determined that the power supply from the camera 20 has been resumed, and the process proceeds to step S404. On the other hand, if the input voltage value is less than or equal to the predetermined value, it is determined that power feeding has not been resumed, and the process returns to step S402 to transmit data relating to the power supply request to the camera 10 again.

  In step S404, the lens microcomputer 101 is operated by receiving an output signal from a switch operated by the user among a plurality of switches 204 to 208 (FIG. 2) provided in the interchangeable lens 10 by interruption processing. The switch is determined, and processing corresponding to the determined switch is executed as described below.

  If there is a signal input from the AF / MFSW 204, an AF / MF switch flag is set in step S405, and the auto focus mode and manual focus mode are switched in step S406.

  When a signal is input from the focus preset SW 205, a focus preset flag (FP flag) is set in step S407, and in step S408, the current focus lens position is detected and the detected position information is stored. Performs focus preset setting processing.

  When there is a signal input from the focus preset playback SW 206, a focus preset playback flag (FP playback flag) is set in step S409, and in step S410, the driving of the lens driving system 102 is controlled to control the focus preset. The focus lens is moved to the focus lens position stored in the setting process.

  When a signal is input from the AF start / stop SW 207, an AF start switch flag is set in step S411. In step S412, whether the AF mode is set and control for starting the AF operation are performed. Do. If a signal is input again from the AF start / stop SW 207 after the AF operation is started, control for terminating the AF operation is performed.

  When a signal is input from the soft focus correction drive SW 208, a soft focus mode flag is set in step S413, and soft focus lens drive control is performed via the lens drive system 102 in step S414, thereby soft focus. In addition to changing the degree of image blur in the mode, the shift of the in-focus position that occurs when the soft focus lens moves is corrected.

  In step S415, the lens status is transmitted to the camera 20 via the light emitting diode 109d, and this process is terminated. Here, the lens status is data relating to the state of each of the switches 204 to 208 provided in the interchangeable lens 10, focus drive, zoom drive, aperture drive enabled / disabled, current drive state, and the like.

  FIG. 5 is a flowchart illustrating an operation when transmitting data regarding a power supply request to the camera 20 in accordance with an operation of a focus ring or a zoom ring provided on the interchangeable lens 10.

  Here, the focus ring and the zoom ring are attached to the interchangeable lens 10 so as to be rotatable around the optical axis. By manually rotating these rings, the focus lens and the zoom lens of the photographing optical system are mounted. Focusing and zooming can be performed by moving in the optical axis direction. In this embodiment, whether or not the focus ring or the zoom ring is operated (the state of the interchangeable lens 10) is detected by the interrupt processing of the lens microcomputer 101.

  In step S501, the lens microcomputer 101 cancels the sleep state (power saving mode) by an interrupt operation and returns to the normal mode.

  In step S502, it is determined whether or not the focus ring has been operated based on the output from the detection unit that detects the operation state of the focus ring. If it is determined that the focus ring has been operated, the process proceeds to step S503. On the other hand, if it is determined that the focus ring is not operated, it is determined in step S502 ′ whether or not the zoom ring has been operated based on the output from the detection unit that detects the operation state of the zoom ring. Do. Here, if the zoom ring has been operated, the process proceeds to step S504, and if it has not been operated, this process ends.

  In step S503, the focus position is detected. For example, there is a method of detecting a pattern when a focus lens is at a certain position by using a brush and detecting a zone corresponding to this pattern as a focus position.

  In step S504, the zoom position is detected. For example, there is a method of detecting a pattern when a zoom lens is at a certain position by using a brush and detecting a zone corresponding to this pattern as a zoom position.

  In step S505, when the user operates the focus ring or zoom ring, there is a possibility that the release operation (operation of the release button) is performed immediately. Therefore, the lens microcomputer 101 makes a power supply request to the camera microcomputer 111 by communication so that the AF operation and the aperture driving in the interchangeable lens 10 can be performed immediately.

  In step S506, it is determined whether power is being supplied. Here, if the power reception voltage (the voltage value input to the lens microcomputer 101) is equal to or greater than the predetermined value, it is determined that the power supply has been resumed, and the process proceeds to step S507. On the other hand, if the received voltage is equal to or lower than the predetermined value, it is determined that the power supply has not been resumed, and the power supply request is transmitted again to the camera microcomputer 111 in step S505.

  In step S507, the lens status is transmitted to the camera microcomputer 111 by communication, and this process ends.

  FIG. 6 is a flowchart showing the operation of the camera microcomputer 111 when a power supply request from the lens microcomputer 101 is received. Hereinafter, each process will be described.

  In step S601, a communication interruption occurs in the camera microcomputer 111, and a power supply request from the lens microcomputer 101 is received.

  In step S602, power supply to the interchangeable lens 10 is resumed. Specifically, the camera microcomputer 111 starts energization of the coil 109a by controlling the driving of the voltage adjusting unit 112. As a result, an electromotive force is generated in the coil 109 a ′ of the interchangeable lens 10, and this power is supplied to each electrical component in the interchangeable lens 10 via the voltage dividing unit 104.

  In step S603, status data transmitted from the lens microcomputer 101 is received. In this operation, a case where the operation of the focus ring or zoom ring in the above-described interchangeable lens 10 is performed (FIG. 5) will be described.

  In step S604, the state change of the interchangeable lens 10 is analyzed based on the status data received in step S603, and if a zoom operation is detected (if the zoom ring is operated in the interchangeable lens 10), the process branches to step S605. If the focus operation is detected (if the focus ring is operated in the interchangeable lens 10), the process branches to step S610.

  In step S605, it is determined whether or not autofocus control is being performed. If AF control is being performed, the process proceeds to step S606. That is, if the zoom ring is operated during AF control, for example, the sensitivity of the focus lens changes, and it is necessary to perform the autofocus again, so the processing from step S606 is performed. On the other hand, if AF control is not in progress, the process proceeds to step S609.

  In step S606, data related to a transmission command of a series of optical data necessary for AF calculation is transmitted to the lens microcomputer 101 by communication, and necessary optical data from the optical data transmitted from the lens microcomputer 101 is transmitted. Is read.

  In step S607, the focus detection state of the photographing optical system is detected by a known method (for example, a contrast detection method or a phase difference detection method) using the focus detection unit 114, and the focus in the lens driving system 102 is determined based on the detection result. The drive amount of the drive motor (the movement amount of the focus lens) is calculated.

  In step S608, the drive amount of the focus drive motor calculated in step S607 is transmitted to the lens microcomputer 101. In step S609, since the open aperture value of the lens may change according to the operation of the zoom ring, the exposure control calculation is re-executed by a known method.

  In step S610, the state of the focus drive motor is determined based on the status data. If the focus drive motor has been driven, the process branches to step S614. If the motor is being driven, the process branches to step S611.

  In step S611, it is determined whether the focus drive motor is accelerating or decelerating based on the status data. Here, when the focus drive motor is accelerating / decelerating, this processing is terminated without detecting the focus adjustment state of the photographing optical system. On the other hand, if the focus drive motor is not accelerating or decelerating, the focus drive motor is driving at a constant speed, and thus the process proceeds to step S612 to detect the focus adjustment state.

  In step S612, the focus detection state of the photographing optical system is detected by a known method (for example, a contrast detection method or a phase difference detection method) using the focus detection unit 114, and the focus in the lens driving system 102 is determined based on the detection result. The drive amount of the drive motor (the movement amount of the focus lens) is calculated.

  In step S613, the drive amount of the focus drive motor calculated in step S612 is transmitted to the lens microcomputer 101.

  In step S614, when the drive of the focus drive motor is stopped, the focus adjustment state of the photographing optical system is detected again by the above-described known method in order to determine the final focus state.

  In step S615, the final focus state is determined in consideration of the aperture value of the lens. If in focus, the process branches to step S617, and if not in focus, the process branches to step S616. In step S616, the focus motor drive amount obtained in step S614 is transmitted to the lens microcomputer 101.

  In step S617, the camera microcomputer 111 captures that the photographing optical system is in focus by driving (sounding or lighting) a sounding element or a display lamp provided in the camera 20 via the control unit 118. Inform the person.

  Next, an operation for detecting the remaining amount of the primary battery 106 provided in the interchangeable lens 10 will be described with reference to a flowchart shown in FIG. Here, as a method of detecting the remaining amount of the battery 106, for example, a method of detecting the remaining amount of battery at a predetermined time interval until the power supply is resumed in a state where the power supply from the camera 20 is stopped. Alternatively, there is a method of always detecting the remaining amount once after the power supply is stopped.

  In step S <b> 701, the lens microcomputer 101 detects the remaining amount of the primary battery 106 based on the output of the remaining amount detection unit 105 after the power supply from the camera 20 is stopped. Specifically, the output voltage value of the primary battery 106 is detected.

  In step S702, it is determined whether the remaining battery level detected in step S701 is greater than or equal to a predetermined amount. Here, if the detected remaining battery level is equal to or greater than a predetermined value, the remaining capacity of the primary battery 106 is sufficient to perform an operation in the control system in the interchangeable lens 10, and a power supply request is issued to the camera 20 side. It is determined that there is no need to perform this process, and this process is terminated. On the other hand, if the remaining battery level is less than or equal to the predetermined amount, it is determined that the remaining capacity of the primary battery 106 is very small, and the process branches to step S703.

  In step S703, a power supply request is transmitted to the camera microcomputer 111 by communication.

  In step S704, it is determined whether power is being supplied from the camera 20 to the interchangeable lens 10. That is, the lens microcomputer 101 determines that power is being supplied if the received voltage is equal to or higher than a predetermined value, and proceeds to step S705. On the other hand, if the received voltage is equal to or lower than the predetermined value, it is determined that power is not supplied, and the power supply request is transmitted again to the camera microcomputer 111 in step S703.

  Here, when it is determined in step S <b> 702 that the primary battery 106 has no remaining battery power, it is necessary to replace the primary battery 106 provided in the interchangeable lens 10. Therefore, in step S <b> 705, the lens microcomputer 101 transmits data related to a request to perform replacement display of the primary battery 106 to the camera microcomputer 111.

  Upon receiving this request, the camera microcomputer 111 drives (sounds and lights) a sounding body and an indicator lamp provided in the camera 20 via the control unit 118, and displays data related to battery replacement on the display unit 117. As a result, the user is warned that the primary battery 106 should be replaced. Note that an indicator lamp or the like may be provided in the interchangeable lens 10 and a warning that the primary battery 106 should be replaced may be issued via the indicator lamp or the like.

  Next, a camera system that is Embodiment 2 of the present invention will be described with reference to FIGS. Here, FIG. 8 is a block diagram showing the configuration of the camera system according to the present embodiment. In FIG. 8, the same members as those described in the first embodiment (FIG. 1) are denoted by the same reference numerals.

  Similarly to the camera system of the first embodiment, the camera system of the present embodiment performs contactless power supply by electromagnetic induction, and is exchanged by optical communication using two sets of light emitting diodes and photodiodes. Data can be exchanged between the lens and the camera.

  On the other hand, this embodiment is different from the first embodiment in that a rechargeable secondary battery is provided in the interchangeable lens 10 instead of the primary battery. As described above, by providing a rechargeable secondary battery in the interchangeable lens 10, it is not necessary to replace the battery in the interchangeable lens 10 as in the first embodiment, and it is easy for the user to use. it can.

  In the camera system of the present embodiment, when the power supply from the camera 20 to the interchangeable lens 10 is suspended, the power supply is performed from the secondary battery 122 to the control system in the interchangeable lens 10. Yes. In this way, by constantly supplying power to the control system in the interchangeable lens 10, it is possible to prevent volatile data in the control system from being lost and taking time at initialization and startup.

  Further, when power is supplied from the camera 20 to the interchangeable lens 10, a predetermined voltage divided by the voltage dividing unit 104 is charged by the secondary battery 122. With the above configuration, trickle charging of the secondary battery 122 is also possible when power is supplied from the camera 20.

  Next, the operation of detecting the remaining amount of the secondary battery 122 provided in the interchangeable lens 10 will be described using the flowchart shown in FIG. Here, as a method of detecting the remaining battery level of the secondary battery 122, as in the case of the primary battery described above, for example, in a state where the power supply from the camera 20 is stopped, a predetermined time until the power supply is resumed. There are a method of detecting the remaining battery level at intervals of, and a method of always detecting the remaining amount once after the power supply is stopped.

  In step S <b> 801, the lens microcomputer 101 detects the remaining battery level of the secondary battery 122 based on the output from the remaining battery level detection unit 105 in a state where power supply from the camera 20 to the interchangeable lens 10 is suspended. Specifically, for example, the output voltage of the secondary battery 122 is detected.

  In step S802, it is determined whether or not the remaining amount of the secondary battery 122 is equal to or greater than a predetermined amount. Here, if the output voltage of the secondary battery 122 detected in step S801 is equal to or greater than a predetermined value, the remaining amount of the secondary battery 122 is sufficient to drive the control system in the interchangeable lens 10, and Thus, it is determined that it is not necessary to supply power, and this process ends.

  On the other hand, if the output voltage of the secondary battery 122 is equal to or lower than the predetermined value, it is determined that the remaining amount is small, and the process branches to step S803. In step S803, a power supply request is transmitted to the camera microcomputer 111 by optical communication.

  In step S804, it is determined whether power is being supplied from the camera 20 side. That is, if the power reception voltage (voltage value input to the lens microcomputer 101) is equal to or greater than a predetermined value, it is determined that power is being supplied to the interchangeable lens 10, and the process proceeds to step S805. On the other hand, if the power reception voltage is equal to or lower than the predetermined value, it is determined that power is not supplied to the interchangeable lens 10, and a power supply request is transmitted to the camera microcomputer 111 again in step S803.

  In step S805, charging of the secondary battery 122 is started using the voltage supplied from the camera 20 side.

  In step S <b> 806, the lens microcomputer 101 detects the remaining amount of the secondary battery 122 based on the output of the remaining amount detection unit 105. Specifically, for example, the output voltage of the secondary battery 122 is detected.

  In step S807, it is determined whether or not charging of the secondary battery 122 has been completed. Here, if the battery output voltage detected in step S806 is equal to or higher than a predetermined value, it is determined that charging of the secondary battery 122 is completed, and the process proceeds to step S808. On the other hand, if the battery output voltage of the secondary battery 122 is equal to or lower than the predetermined value, it is determined that the charging is insufficient and the charging is continued.

  In step S808, data indicating that charging has been completed is transmitted to the camera microcomputer 111 via optical communication. Receiving this data, the camera microcomputer 111 stops the power supply to the interchangeable lens 10 by controlling the driving of the voltage adjustment unit 112.

  In the first embodiment and the second embodiment described above, the case where optical communication using a light emitting diode and a photodiode is used as the communication means between the camera and the interchangeable lens. However, the communication means using the electrical contacts (the interchangeable lens and the camera, respectively) The present invention can also be applied to a configuration in which electrical terminals are provided on the mounting portion and connected to each other.

  Further, as the secondary battery 122 in the second embodiment, not only a secondary battery having a relatively large capacity such as a nickel hydride secondary battery or a lithium ion secondary battery but also a power storage means for temporarily storing power such as a capacitor. It can also be used.

  Furthermore, in the first and second embodiments described above, the camera system including the camera and the interchangeable lens that is detachably attached to the camera has been described. However, the camera system is not limited to the interchangeable lens, and is detachably attached to the camera. Any device can be used as long as it receives power supply from the camera. Specifically, the present invention can be applied to an illumination device that irradiates illumination light to a subject.

1 is a configuration block diagram of a camera system in Embodiment 1 of the present invention. The block diagram showing the detection of the operation system of a taking lens. 5 is a flowchart regarding the operation of the taking lens in the first embodiment. 5 is a flowchart regarding the operation of the taking lens in the first embodiment. 5 is a flowchart regarding the operation of the taking lens in the first embodiment. 6 is a flowchart regarding the operation of the camera body in the first embodiment. 5 is a flowchart regarding the operation of the taking lens in the first embodiment. FIG. 6 is a configuration block diagram of a camera system in Embodiment 2 of the present invention. 9 is a flowchart relating to the operation of a taking lens in the second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101,102: Lens microcomputer 102: Focus drive system 103: Diaphragm drive system 104: Voltage divider 105: Remaining amount detection 106: Primary battery 107, 110: Interface 108: Lens unit 109a: Non-contact power supply coil 111: Camera Microcomputer 112: Voltage adjustment unit 113: Power source 114: Focus detection unit 115: Photometry unit 116: Shutter unit 117: Display unit 118: Other control unit 119: SW1 120: SW2 121: SWM 122: Secondary battery

Claims (9)

A camera accessory attached to the camera,
A drive system that receives power supply to drive the operating unit in the camera accessory;
A control system that receives power supply and controls the camera accessory;
Power supply means for receiving operating power from the camera and supplying operating power to the drive system and the control system;
An accessory power supply that supplies second power only to the control system when the supply of the first power from the camera is stopped;   The camera accessory according to claim 1, wherein the second power is lower than the first power.   The camera accessory according to claim 1, wherein the power supply unit receives the first power from the camera in a contactless manner. Communication means for communicating with the camera;
The control system requests the camera to start supplying the first power via the communication unit when the state of the camera accessory changes after the supply of the first power is stopped. The camera accessory according to any one of claims 1 to 3, wherein a signal is transmitted. Having a communication means for communicating with the camera, and the accessory power supply is a primary battery,
The control system transmits a signal indicating that the remaining battery level has decreased to the camera via the communication unit when the remaining battery level of the accessory power source becomes a predetermined level or less. The camera accessory according to any one of claims 1 to 4. Having a communication means for communicating with the camera, and the accessory power supply is a secondary battery,
After the supply of the first power is stopped, the control system is configured to supply the first power to the camera via the communication unit when the remaining battery level of the accessory power source becomes a predetermined level or less. The camera accessory according to any one of claims 1 to 5, wherein a signal requesting the start of supply is transmitted. The accessory power source is a secondary battery;
The camera accessory according to any one of claims 1 to 6, wherein the power supply unit charges the accessory power source using the first power.   8. The camera accessory according to claim 1, wherein the control system holds volatile data by the second power when the supply of the first power is stopped. The camera accessory according to any one of claims 1 to 8,
A camera system comprising: the camera accessory mounted; and the camera supplying the first power to the camera accessory.