JP2014157200A - Flash device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flash device that stops charge of a main capacitor of a flash device when firming up the flash device, discharges a charge voltage of the main capacitor until the charge voltage reaches a voltage lower than a predetermined charge voltage (a voltage capable of light emission), then, starts firming-up, and can prevent wrong light emission even when a firm of the flash device performs a wrong operation and a light emission circuit performs a wrong operation.SOLUTION: In a camera system in which a flash device is detachably attachable to a camera, a program area capable of firming up is built in the flash device, and the program area having a firm program of the flash device written can be overwritten by an instruction from the camera via communication, at a time of firming up, charge of a main capacitor of the flash device is stopped, and firm-up is started after a charge voltage of the main capacitor is discharged to a voltage lower than a predetermined charge voltage.

Description

  The present invention relates to a flash device, and more particularly to a flash device that can be upgraded.

  Conventionally, various user firmware upgrade systems for accessories have been proposed. For example, in Patent Document 1, the camera stores firmware version information of accessories in a memory. Then, when a new firmware version is released by external communication, a method for downloading the firmware and upgrading the firmware of the connected accessory has been proposed.

JP 2008-116660 A

  In the case of accessory firmware upgrade, unlike the firmware upgrade of a camera alone, most systems that perform firmware upgrade by connecting to a camera can cause the firmware upgrade to fail due to disconnection from the camera during accessory firmware upgrade. There is sex.

  In the above-mentioned patent document, there is no description regarding a firmware upgrade failure.

  In addition, when the firmware upgrade of the flash device fails, the firmware description becomes incorrect due to the failure, the firmware malfunctions, and in some cases, the flash device may erroneously emit light.

  In order to achieve the above object, the flash device (230 in FIG. 1) can be attached to and detached from the camera (100 in FIG. 1), and the flash device (230 in FIG. 1) can be upgraded to a program area (234 in FIG. 1). ) In the camera system that can rewrite the program area (234 in FIG. 1) in which the firmware program of the flash unit (230 in FIG. 1) is rewritten by an instruction from the camera through communication. At that time, stop charging the main capacitor of the flash unit (234 in FIG. 1), discharge the main capacitor charging voltage to a voltage lower than the predetermined charging voltage (S402 in FIG. 7), and then start the firmware upgrade. It is a feature.

  According to the present invention, when the flash is upgraded, charging of the main capacitor of the flash is prohibited, and further, the charging voltage of the main capacitor is discharged to a voltage lower than a predetermined voltage (for example, light emission possible voltage). By doing so, it is possible to provide a flash device that can prevent erroneous light emission even if the firmware of the flash device fails and the flash device firmware malfunctions and the light emitting circuit malfunctions.

It is a block diagram showing a system configuration diagram including a camera and a flash device. It is a flowchart figure which shows operation | movement of a camera. There is a camera menu screen explaining the firmware update. It is a flowchart of a camera showing an operation of firmware update. It is a flowchart figure which shows the operation | movement of flash. FIG. 10 is a flash flowchart showing the operation of flash communication post-processing 1; FIG. 5 is a flash flowchart showing the operation of firmware update. FIG. 10 is a flash flowchart showing the operation of flash communication post-processing 2.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Example 1]
1 to 8 are diagrams according to a first embodiment of the present invention.

  Hereinafter, the operation of the embodiment will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a digital camera system to which a flash device according to the first embodiment of the present invention can be attached and detached. In FIG. 1, reference numeral 100 denotes a single-lens reflex camera (hereinafter referred to as a camera), 220 denotes an interchangeable lens that can be attached to and detached from the camera 100, and 230 denotes an external flash device that can be attached to and detached from the camera 100.

  In the camera 100, reference numeral 2 denotes a full-surface half mirror without a movable mechanism, and guides light incident from the lens 1 to an image sensor 5 and a focus detection device 6 to be described later. Reference numeral 4 denotes a shutter for controlling the exposure amount of the image sensor described later. Reference numeral 5 denotes an image sensor composed of a CCD sensor, a CMOS sensor, or the like. The image sensor 5 photoelectrically converts the subject image formed by the interchangeable lens 220.

  Reference numeral 16 denotes an A / D converter that converts an analog imaging signal from the imaging device 5 into a digital signal. A timing generation circuit 18 supplies a clock signal to the image sensor 5, the A / D converter 16, and a D / A converter 26 described later. The timing generation circuit 18 is controlled by a memory control circuit 22 and a system control circuit 50 described later. An image processing circuit 20 performs various image processing such as pixel interpolation processing, color conversion processing, and AWB (auto white balance) processing on the digital image pickup signal from the A / D converter 16 or the memory control circuit 22. An image signal (video) is generated.

  Reference numeral 6 denotes a focus detection device, which includes a phase difference detection sensor having a plurality of distance measuring areas. The system control circuit 50 performs accumulation control and readout control of the focus detection device, and calculates a defocus amount by a known phase difference detection method. Reference numeral 50 denotes a system control circuit which controls the focus drive and the aperture drive of the lens 220 by exchanging from the overall operation of the camera 100, the defocus amount, and the like. In addition, communication with the external flash 230 is performed to control the external flash such as the light emission timing and light emission amount of the external flash and pre-light emission information (accumulation start time and accumulation time). Furthermore, the system control circuit 50 functions as a storage control unit and a display control unit (not shown).

  The memory control circuit 22 controls the A / D converter 16, the timing generation circuit 18, the image processing circuit 20, and an image display memory 24, a D / A converter 26, a memory 30, and a compression / decompression circuit 32 described later. . An image signal from the image processing circuit 20 or a digital image pickup signal from the A / D converter 16 is sent to the image display memory 24, the memory 30, and the system control 50 via the memory control circuit 22.

  Reference numeral 28 denotes an image display unit (display means) constituted by an LCD or the like. Display image data written in the image display memory 24 such as a face detection result to be described later is sent to the image display unit 28 via the D / A converter 26 and displayed on the image display unit 28. The memory 30 stores the generated still image and moving image. The memory 30 is also used as a work area for the system control circuit 50.

  A face detection unit 31 performs a predetermined face detection operation on the image data from the image processing circuit 20 or the image data from the memory control circuit 22. The face detection operation performed by the face detection unit 31 is not particularly limited to the processing method described above as long as it is a method that uses image data of a subject for the face detection operation. A compression / decompression circuit 32 compresses / decompresses image data by adaptive discrete cosine transform (ADCT) or the like, reads an image stored in the memory 30, performs compression processing or decompression processing, and stores the processed data again in the memory. Write to 30.

  Reference numeral 40 denotes an exposure control circuit for controlling the shutter 4, and also controls the aperture 224 of the interchangeable lens 220 via the system control circuit 50. Reference numeral 52 denotes a memory for storing data such as constants, variables and computer programs for operation of the system control circuit 50.

  54 is an electrically erasable / recordable nonvolatile memory such as an EEPROM. Reference numeral 56 denotes an information output unit that outputs information indicating the operating state of the camera 100, a message, and the like using characters, images, sounds, and the like. The information output unit 56 includes a liquid crystal display element, a speaker, and the like.

  Reference numeral 60 denotes a mode dial switch, which is operated to switch and set each function such as power ON / OFF, imaging mode (still image imaging mode or moving image imaging mode), and reproduction mode. Reference numeral 62 denotes an imaging preparation (SW1) and an imaging start switch (SW2). When a shutter button (not shown) performs a first stroke operation (half-press), SW1 is turned on to prepare for imaging such as photometry (AE processing) and AF processing. Start operation. Furthermore, SW2 is turned ON by the second stroke operation (full press) of the shutter button, and the imaging operation is started.

  The imaging operation referred to here includes the light emission operation of the flash 230, the opening / closing operation of the shutter 4, the operation of generating an image signal in the image processing circuit 20 based on the imaging signal from the imaging device 5, and the image signal to the memory control circuit 22. Operation to write to the memory 30 via Also included is an operation of reading out image data from the memory 30, compressing the image data by the compression / decompression circuit 32, and recording it on recording media 200 and 210 described later. These series of imaging operations can also be referred to as recording image acquisition operations. The recording media 200 and 210 are constituted by a semiconductor memory, an optical disk, or the like.

  Reference numeral 70 denotes an operation unit including various buttons, a touch panel, and the like, and is operated to display a menu screen for selecting functions and various settings of the camera 100 and determining menu items. Reference numeral 78 denotes a power control circuit, which includes a battery detection circuit that detects the remaining battery level, a DC-DC converter that converts a power supply voltage from the battery into a predetermined operating voltage, and the like.

  A battery 80 is detachable from the camera. A power source 86 is a primary battery such as an alkaline battery or a lithium battery, or a secondary battery such as a NiMH battery or a Li battery. Reference numerals 82 and 84 denote connectors for electrical connection between the power source 86 and the camera 100. Reference numerals 90 and 94 denote interfaces for communicating with the recording media 200 and 210, and reference numerals 92 and 96 denote connectors connected to the recording media 200 and 210. A recording medium attachment / detachment detector 98 detects whether or not the recording mediums 200 and 210 are attached to the connectors 92 and 96.

  A communication unit 110 has communication functions such as RS232C, USB, IEEE1394, and wireless communication. Reference numeral 112 denotes a connector for connecting another device to the camera 100 via the communication unit 110, and an antenna is connected when performing wireless communication. The recording media 200 and 210 include interfaces 204 and 214 for performing communication with the camera 100 and connectors 206 and 216 for performing electrical connection with the camera 100. In the recording units 202 and 212, compressed image data output from the camera 100 is written.

  In the interchangeable lens 220, reference numeral 1 denotes an imaging lens group including a plurality of lenses, which includes a focus lens that moves in the optical axis direction and performs focus adjustment, and a zoom lens that moves in the optical axis direction and performs zooming. A diaphragm 224 adjusts the amount of light reaching the image sensor 5. The imaging lens group 1 and the diaphragm 224 constitute an imaging optical system.

  A lens control circuit 226 controls an actuator (not shown) that drives the focus lens, the zoom lens, and the diaphragm 224 in accordance with a control signal from the system control circuit 50. The lens control circuit also has a memory function for storing constants, variables, programs, and the like for taking lens operations. In addition, it also has a nonvolatile memory function for storing identification information such as a number unique to the photographing lens, management information, function information such as an open aperture value, a minimum aperture value, a focal length, and current and past set values.

  A connector 228 is connected to the communication contact 41 of the camera 100 and enables communication between the lens control circuit 226 and the system control circuit 50. Further, the connector 228 supplies the power supply voltage from the power supply 86 into the interchangeable lens 220.

  A flash control unit 232 includes a rewritable program area 234 and is also connected to an unillustrated EEPROM. The camera side connection unit 45 and the flash side connection unit 231 communicate with the camera 100. Transmission of various flash information (safe mode status, firmware version, guide number information, etc.) and various information from the camera (shooting mode, shutter speed, aperture, ISO, zoom position, pre-flash information, etc.) and instructions (firmware up, flash Timing). Further, the flash light emission circuit 236 and the power supply control 233 communicate with each other. The flash light emission circuit 236 starts / stops light emission, and the charge / power supply control 233 controls charging start / stop / discharge of a capacitor for light emission. Communicating. In addition, the charging / power control 233 notifies the flash controller 232 of the charging voltage state of the capacitor.

Therefore, the flash control unit 232 can detect the charging voltage state of the capacitor, and can start, stop, or discharge the capacitor.
The charging / power supply control 233 includes a DC-DC converter that converts a power supply voltage into a predetermined operating voltage, and power is supplied from the battery 238. In addition, the charging / power control 233 creates a power source for the external flash device 230.

  Reference numeral 238 denotes a secondary battery, and a secondary battery such as a NiMH battery or a Li battery is used. A flash light emitting circuit 236 is connected to the light emitting unit 237 and starts or stops emitting light according to an instruction from the flash control 232.

  The operation of the camera will be described in detail with reference to FIGS. In S001 of FIG. 2, the camera performs initial settings such as register initialization, data initialization, and peripheral circuit initialization.

  In step S002, communication with the external flash device 230 is performed, and various types of external flash information (safe mode state, firmware version, guide number information, etc.) are received. In S003, state detection of a camera setting button (not shown), a shooting mode dial, a main electronic dial, a sub electronic dial, and the like is performed. If the setting button is on in S004, the process proceeds to S005, and various setting operations are performed. In various setting operations, a setting menu is displayed on the image display unit 28, and the user can select various setting items from the setting menu and perform various settings. If the setting button is off, the process proceeds to S006.

  Firmware updates (camera and flash) can also be started from the settings menu. Here, the flash firmware upgrade method from the camera (setting menu) will be described in detail with reference to FIGS.

  3 are screens from the start to the end of flash firmware upgrade displayed on the image display unit 28. When “firmware” is selected from the setting items of MENU 4 in FIG. 3a, the screen shifts to the screen in FIG. 3b. By the way, in the setting items of MENU4, “camera setting contents” displays various setting states (image quality setting, white balance, etc.) set for the camera on the image display unit 28 when the item is selected. “Release” sets various settings (image quality setting, white balance, etc.) set to the camera to the default state when the item is selected.

  FIG. 3B shows a screen for selecting an item for updating firmware, displaying an item for updating firmware (camera and flash) and displaying the current version of the item. When “flash” is selected from the selection items, the process proceeds to c of FIG. Also, when “camera” is selected from the selection items, the screen shifts to a firmware update screen for a camera (not shown).

  When “OK” is selected in c of FIG. 3, the screen shifts to the flash firmware selection screen of d of FIG. 3. If "Cancel" is selected, the process returns to b of FIG. In FIG. 3d, the flash firmware recorded in the recording medium 200 or 210 can be displayed on the screen and selected. The user needs to record flash firmware in the recording medium (CF card or the like) 200 or 210 in advance. Further, the latest firmware may be downloaded to the recording medium 200 or 210 by the communication unit 110 via the Internet.

  When the flash firmware is selected in FIG. 3d, the process proceeds to e in FIG. 3 to start updating the flash firmware.

  Here, the firmware update of the flash will be described in detail with reference to the flowchart of the camera in FIG.

In S101 of FIG. 4, communication with the flash is performed and a firmware upgrade instruction is notified.
In S102, when updating the flash firmware is started, the progress status is set to 0% and displayed on the image display unit 28 (0% display at e in FIG. 3).

  In S103, the flash firmware is read from the recording medium 200 or 210 into the RAM in the camera. The rewrite area (start address to end address) is transmitted to the flash. There are a plurality of rewriting areas (for example, 1 block = 1 Kbyte), and the end area is predetermined in this embodiment.

  In S104, program data corresponding to the rewrite area is transmitted to the flash. In S105, the process waits until a write completion notice or a firmware upgrade failure notice comes from the flash. If there is a firmware upgrade failure notification in S106, the process proceeds to S107, an error is displayed, and the process ends. Otherwise, the process proceeds to S108.

  In S108, it is determined whether the rewriting area is the final area. If it is not the final area, the process proceeds to S109, and if it is the final area, the process proceeds to S110. In S109, the firmware update progress status is displayed on the image display unit 28 from the transmitted data amount and the total data amount to be transmitted (e in FIG. 3), and the process returns to S103. In S110, a firmware update completion screen (f in FIG. 3) is displayed on the image display unit 28, and the process returns (returns to S002 in FIG. 2).

  Returning to FIG. 2, if the photometry / AF start SW is off in S006, the process proceeds to S014, and if not, the process proceeds to S007. In S007, various pieces of information on the mounted photographing lens are read. When acquiring lens information from the photographic lens 220, the system control 50 communicates with the photographic lens 220 to acquire lens information of the photographic lens 220. The lens information includes information such as lens specific information, focal length, aperture value, and focus lens position.

  In step S008, distance measurement is performed by a known phase difference detection method in order to focus on the subject. In step S009, the lens driving amount is calculated based on the data obtained by the distance measurement calculation to drive the lens. In S010, photometric calculation processing is performed to determine the shutter time (CMOS accumulation time), aperture value, etc. from the output from the photometry circuit, calculation ISO, and camera settings such as the shooting mode.

  In S011, camera information such as the shutter speed and aperture value obtained by photometric calculation or the like is displayed on the display unit. If the photographing operation SW is off in S012, the process proceeds to S014, and if the photographing operation SW is on, the process proceeds to S013. In S013, well-known gain setting, accumulation operation, and readout operation of the image sensor 5 are performed, and still image capturing operations such as image processing and image writing are performed, and the process loops to S002.

  In S014, if the camera power SW is on, the process loops to S002, and if it is off, the process proceeds to S015. In step S015, in order to end the operation of the camera, an instruction to turn off the power to the peripheral circuits and an end setting such as data saving are performed, and the operation ends.

  5 to 8 are flowcharts of the flash 230, and the operation of the flash will be described in detail with reference to the flowcharts.

  In S201 of FIG. 5, the flash microcomputer is activated, and initialization processing of terminals connected to the microcomputer, reading of external EEPROM data, and data initialization of the internal RAM and the like are performed.

  In step S202, communication settings are performed in order to communicate with the connected camera. In S203, a flash device switch (power switch or the like) is detected.

  In S204, if the power switch is turned off due to the switch detection in S203, the process proceeds to S205, where an end setting such as a power-off process is performed, and the flash operation is finished. If the power switch is not OFF, the process proceeds to S206.

  If the firmware up state flag stored in the EEPROM (not shown) is 1 in S206, the process proceeds to S207, and the flash state stored in the internal RAM is stored as the safe mode. Otherwise, the process proceeds to S208 and the flash state is stored as the normal mode.

  If the flash state is the safe mode in S209, the process proceeds to S210, and if not, the process proceeds to S214. If there is no communication request from the camera in S210, the process returns to S203, and if there is a communication request, the process proceeds to S211. In S211, communication with the camera is performed. The process proceeds to S212. In S212, the content of communication with the camera is confirmed.

  Here, the confirmation of communication contents will be described in detail with reference to the flowchart of post-communication processing 1 in FIG.

In S301 of FIG. 6, if the communication content from the camera is a firmware upgrade request, the process proceeds to S302, the firmware upgrade process is executed, and if not, the process proceeds to S303.
Here, the firmware upgrade process will be described in detail with reference to the flowchart of FIG.

  In S401 of FIG. 7, the firmware up state flag stored in the EEPROM is set to 1, and the firmware is being upgraded.

  In step S402, communication with the charging / power supply control 233 in FIG. 1 is performed, and the main capacitor discharging instruction is issued up to the charging voltage level at which charging of the main capacitor for light emission is stopped and no erroneous light emission occurs.

  The charge stop control of the main capacitor is performed by stopping the booster circuit that is boosting the battery voltage to a high voltage that supplies the battery voltage to the main capacitor using a known stop circuit. Also, the discharge control of the main capacitor is performed by using an IGBT element or a thyristor element in a known discharge circuit.

  In S403, communication with the camera is performed, and a rewriting area (start address to end address) is received. In S404, program data is received. In S405, the program currently written in the rewriting area is deleted. In S406, a process of writing the data received in S404 in the rewriting area is executed.

  In S407, if there is no difference between the written program data and the received program data as a code check, the process proceeds to S410 as a check OK, and if it is a check NG, the process proceeds to S408. In step S408, the camera is notified that the firmware upgrade has failed.

  In S409, the fact that the firmware upgrade has failed is displayed as an error display on a flash display member (not shown), and the process ends. In S410, a notification of writing completion is sent to the camera.

  In S411, it is determined whether the rewriting area is the final area. If it is not the final area, the process proceeds to S403. If it is the final area, the process proceeds to S412 to clear the firmware up state flag to 0 and the firmware is not being upgraded. Remember.

  In S413, since the flash program rewriting has been completed, an internal reset is performed once to return the flash operation start to the start of FIG.

  Returning to FIG. 6, if the communication from the camera is information communication from the camera (shooting mode, shutter speed, aperture, ISO, zoom position, pre-flash information, etc.) in S303, the process proceeds to S304 and is received. Information is stored in RAM. Otherwise, the process proceeds to S305.

  If the communication from the camera is a flash information request (safe mode state, firmware version, guide number information, etc.) in S305, the process proceeds to S306 and the flash information is transmitted to the camera. Otherwise, return.

  Returning to FIG. 5, in step S213, information from the camera, flash setting status, and the like are displayed on a flash display unit (not shown), and the flow returns to step S203. Therefore, at the time of safe mode, it does not transfer to charge control of S217.

  If there is no communication request from the camera in S214, the process proceeds to S217, and if there is a communication request, the process proceeds to S215.

  In S215, communication with the camera is performed. The process proceeds to S216. In S216, the content of communication with the camera is confirmed.

  Here, the confirmation of communication contents will be described in detail with reference to the flowchart of post-communication processing 2 in FIG. In S501 of FIG. 8, if the communication content from the camera is a firmware upgrade request, the process proceeds to S502, the firmware upgrade process is executed, and if not, the process proceeds to S503.

  The firmware upgrade process in S502 is the same as S302 in FIG. In S503, if the communication from the camera is the main flash communication, the process proceeds to S504, and the main flash process is executed in S504. Otherwise, the process proceeds to S505.

  If the communication from the camera is the flash pre-flash communication in S505, the process proceeds to S506, and the pre-flash processing is executed in S506. Otherwise, the process proceeds to S507.

  If the communication from the camera is information communication from the camera (shooting mode, shutter speed, aperture, ISO, zoom position, pre-flash information, etc.) in S507, the process proceeds to S508 and the received information is stored in the RAM. . Otherwise, the process proceeds to S509.

  If the communication from the camera is a flash information request (safe mode state, firmware version, guide number information, etc.) in S509, the process proceeds to S510, and the flash information is transmitted to the camera. Otherwise, return.

  Returning to FIG. 5, in S217, charging control of the main capacitor of the flash is executed. If it is not charged, charging is started. If it is charged, the charging voltage is periodically checked to prevent overcharging.

  In S218, information from the camera, flash setting status, etc. are displayed on a flash display means (not shown), and the process returns to S203.

  As described above, when the flash is upgraded, the main capacitor of the flash is stopped and the main capacitor is discharged to a voltage lower than a predetermined charging voltage (a voltage level that does not cause erroneous light emission). Thus, it is possible to provide a flash device that can prevent erroneous light emission even if the firmware of the flash device fails and the flash device firmware malfunctions and the light emitting circuit malfunctions.

  In addition, it is possible to provide a flash device that operates in the safe mode and does not charge the main capacitor when the firmware upgrade fails.

230 External Flash Device 232 External Flash Control Unit 233 Charging / Power Control 234 Program Area 236 Flash Light Emitting Circuit 237 Light Emitting Unit

Claims (2)

  A flash device that can be attached to and detached from the camera. The flash device has a built-in program area that can be upgraded, and the program area in which the firmware program of the flash device is written can be rewritten by instructions from the camera via communication. In a camera system, a flash device is characterized in that when a firmware is upgraded, the main capacitor of the flash device is stopped from being charged, and the firmware is started after the charging voltage of the main capacitor is discharged to a voltage lower than a predetermined charging voltage.   2. The flash device according to claim 1, wherein the flash device stores a firmware up state and operates in a safe mode while the firmware upgrade is not completed, and prohibits charging of the main capacitor in the safe mode.