JPH0961903A - Emitted light quantity controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the adjustment of the emitted light quantity in a factory and to obtain an exact emitted light quantity control means by storing the reference data meeting a prescribed guide number in a storage means and forming emitted light quantity data in accordance with this data in case of photographing. SOLUTION: The output voltage of a buffer amplifier 43 corresponding to an integrated quantity attains a voltage value Vfull when full light emission is executed in a prescribed zoom position in the constitution of a flash light emitting device as the emitted light quantity controller. The voltage of this Vfull is previously stored in the writable storage means as the light emission reference value at the time of adjusting the flash light emitting device. The voltage corresponding to the emitted light quantity required for the Vfull, for example, the voltage of Vfull-4F in order to make light emission (reduced by four steps) of 1/16 of the full light emission, is set as a comparative voltage and the light emission is so stopped that the integrated output attains this voltage at the time of controlling the light emission. As a result, the relative light emission for the max. emitted light quantity is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emission control device for a flash light emitting device.

[0002]

2. Description of the Related Art Conventionally, a method shown in FIG. 16 is generally performed as an example of a flash light control device for controlling light emission of a flash light emitting device with a predetermined light amount. In the figure, 100 is a battery, 1
Reference numeral 01 is a DC / DC converter that converts the battery voltage into a high voltage capable of strobe light emission, 102 is a main capacitor that charges the light emission energy, 103 is a coil that limits the light emission current during light emission, 104 is a trigger circuit, and 105 is a trigger switch. Reference numeral 106 denotes an Xe tube which is a light emitting means, 107 denotes an emission stop circuit, 108 denotes a light receiving element for monitoring the light of the Xe tube 106, 109 denotes a LOG amplifier for logarithmically converting the photocurrent received by the light receiving element 108, and 110 denotes an integrating circuit. , 111 are variable resistors that divide the voltage of the reference voltage 114 together with the resistor 112 to adjust the light emission amount of the Xe tube 106. 113
Is a comparator.

In order to cause the strobe to emit a predetermined amount of light with the above configuration, the variable resistor 111 is adjusted as much as the predetermined amount of emission while monitoring the amount of emission of the strobe with an external measuring device during adjustment processing in a factory or the like. Was going by.

[0004]

However, in the above-mentioned embodiment, in order to obtain a predetermined amount of light, it is necessary to precisely adjust the variable resistance, so that there is a drawback that the adjustment process requires cost and time.

Further, when performing so-called auto-zooming, which automatically changes the flash emission angle according to the focal length of the lens for stroboscopic photography, in order to obtain a predetermined amount of light for each focal length, further There is a drawback that the circuit becomes complicated because an analog adjusting means is required.

[0006]

The present invention has been made in view of the above matters, and in claim 1, a capacitor for accumulating a charge for flash light and a light emission for flashing light by discharging the charge of the capacitor. Means, light emission amount data setting means for setting light emission amount data by the light emitting means, and light emission amount control means for controlling the light emission amount by the light emitting means at the time of photographing based on the data set by the setting means. At the same time, storage means for storing, as reference data, the light emission amount data corresponding to the integrated value of the light reception output by the photometric means of the flash light emission when the flash light emission is performed by the light emitting means while the capacitor is charged to a predetermined voltage. And a processing means for setting the light emission amount data in the light emission amount data setting means on the basis of the reference data of the storage means. , The integral value of the photometric output of the flash emission when the flash is emitted with the main capacitor charged to a predetermined voltage is stored as reference data, and when shooting, for example, to the guide number specified for manual flash When setting the corresponding light emission amount data, the reference data is used as the data corresponding to the predetermined guide number, and the light emission amount data corresponding to the designated guide number is formed from the reference data, whereby the adjustment process of the light emission amount data is performed. It is intended to provide a light emission amount control device capable of performing accurate light emission amount control after being simplified.

According to a second aspect of the present invention, the flash light emission during flash light emission is measured by an external device, and the flash light emission is controlled in the light emission amount control device when the measured value reaches a predetermined value. The integrated output that is directly integrated is stored in the storage means as reference data, and when photographing,
This reference data is processed as a light emission amount corresponding to a predetermined guide number, light emission amount data corresponding to a specified light emission amount (guide number) is formed, and light emission amount control is performed based on this data. This simplifies the process of adjusting the light emission amount data as in the case of claim 1,
It is intended to provide a light emission control device for performing more accurate flash light emission amount control. According to a third aspect of the present invention, the reference data is set in a storage means in an adjusting process in a factory, and in the fourth aspect, light emission amount data for a designated guide number based on the reference data is formed by dividing the reference data. The fifth aspect provides a specific configuration of the light emission amount control based on the light emission amount data. According to a sixth aspect of the present invention, by changing the distance between the light emitting means and the Fresnel lens, the reference data for each zoom position is stored in the storage means as reference data in a so-called zoom strobe that changes the light emission characteristics, and the zooming is performed by this. It is intended to provide a light emission amount control device that realizes adjustment and control of a light emission amount with respect to a position change.

[0008]

1 is a circuit diagram showing an example of a light emission amount control device according to the present invention. In the figure, 1 is a battery as a power source, 2 is a known DC / DC converter as a step-up circuit for converting the battery voltage into high voltage, 3 and 4 are resistors and 5
Is a main capacitor for charging light emission energy, 6 is a thyristor for activating a light emission trigger signal, 7 and 8 are resistors, 9
Is a coil that limits the current during light emission, 10 is a diode that circulates the energy stored in the coil 9 when light emission is stopped, 11 is a Xe tube that is a light emitting means, 12 is a trigger electrode,
13 is a trigger transformer for generating a trigger voltage for Xe tube light emission, 14 is a trigger capacitor, 15 is a resistor for charging the trigger capacitor, 16 is an IGBT as a control element for performing light emission / stop control, and 17 is a PNP transistor. , 18, 19, 20, 21 are resistors, 22 is an NPN transistor, 23, 24 are N-channel FETs, 25, 2
6 is a resistor, 27 is a zener diode for generating a gate voltage enough to turn on the IGBT 16, and 28 is a capacitor for stabilizing the gate voltage. Reference numeral 30 is a photometric sensor, which is a light emission amount monitoring means of the Xe tube 11, and directly receives the light emission of the Xe tube 11, 31 is an operational amplifier 32, 33 is a resistor, 34 is an operational amplifier, and 35 is a diode. , 34, and 35 form a logarithmic amplifier circuit. 36,
37 and 38 are resistors, 39 NPN transistors, and 40 are capacitors, which integrate the output voltage of the logarithmic amplifier circuit, and the transistor 39 controls the start and stop of the integration. Reference numerals 41 and 42 are resistors, and 43 is an operational amplifier, which serves to buffer the integrated output. Reference numeral 44 is a comparator for generating a light emission stop signal when the light emission output of the Xe tube reaches a predetermined value, 45 is an AND circuit, and 46 is a power supply circuit for generating a bias voltage.

Reference numeral 50 is a microcomputer (microcomputer) as a processing circuit, 51 is an EEPROM which is a light emission reference amount storage means (writable storage means), and a flash ROM may be used instead of the EEPROM. A power switch, 53 to 57 are connection terminals to the camera, 53 is an X contact, 54 is a clock terminal for serial communication, 55 is a serial data input terminal, 56 is a serial data output terminal, and 57 is a charging signal output terminal. 5,
Reference numeral 8 is an NPN transistor, and 59, 60 and 61 are resistors. Reference numeral 62 is an LED which is a display means for indicating that the voltage of the main capacitor 5 has reached the voltage capable of emitting light, and 63 is a Fresnel lens for collecting light which is installed in front of the Xe tube 11 ′ which is a flash means and is in a fixed state. 64 is a reflector that collects the light from the Xe tube 11 ′, and 65 is a reflector that guides the light from the Xe tube 11 ′ to the photometric sensor 30 ′. The reflector 6
5. The sensor 30 ′ reflection shade 64 has an integral structure. Reference numerals 66 and 67 are racks and pinion gears for driving the reflection shade 64 to a position according to the irradiation angle, 68 is a motor for generating a zoom drive force, 69 is a motor drive circuit, and 70 is a motor drive circuit.
Is an encoder switch indicating the position of the reflective shade 64.
The Xe tube 11 'and the sensor 30' are indicated by 1 in the circuit diagram.
Although the same as 1 and 30, they are shown for the sake of explanation in order to show the mechanical arrangement relationship.

Next, each terminal of the microcomputer 50 will be described.
CNT is an output terminal that controls the start / stop of oscillation of the DC / DC converter 2. For the sake of explanation, charging is started at Hi and stopped at Lo, AD0 indicates the voltage of the main capacitor 5 by the resistor 3,
An input terminal for inputting to the first AD converter in the microcomputer 50 for inputting after being divided by 4 and for converting into a digital signal, TRI is a light emission start signal output terminal, and STOP is light emission output from the AND gate 45. A stop signal input terminal for inputting a stop signal, INT is a light emitting means Xe
An integration permission signal output terminal for starting / inhibiting integration of an electric signal corresponding to the optical output of the tube 11, AD1 is an operational amplifier 43
In order to convert the buffered integrated output voltage output by the second AD into the digital signal,
DA0 is an input terminal for inputting to the converter, DA0 is a voltage output terminal for outputting a reference voltage according to the light emission amount of the light emission stop comparator 44, and ECK is a light emission reference amount storage means connected to the outside of the microcomputer 50. An output terminal for outputting a communication clock for serial communication with an EEPROM (writable storage means), EDI is a serial data input terminal from the storage means, EDO is a serial data output terminal to the storage means, POW is the power switch 52
Input terminal for inputting the state of, the OFF input terminal for turning off the strobe when connected to the power switch 52, the ON input for turning on the strobe when connected to the power switch 52. Terminal, X is an input terminal of a light emission signal from the camera, CK is an input terminal of a synchronous clock for performing serial communication with the camera, DI is an input terminal of the serial communication data, and DO is a data output terminal of the serial communication. is there. Although the storage means 51 is set outside the microcomputer in this embodiment, it goes without saying that it may be built in the microcomputer. CHG is an output terminal for notifying the camera that the voltage of the main capacitor 5 has reached the light emission enable voltage, LED is a display output terminal for similarly indicating that the light emission enable voltage has been reached, and COM0 is the zoom encoder switch 70. , ZM0 to ZM3 are zoom signal input terminals that read the zoom encoder switch 70, and
Reference numerals 0 and Z1 are control output terminals for controlling the motor control circuit 68 for driving the zoom drive motor 67.

In the embodiment shown in FIG. 1, full light emission is performed at each zoom position at the time of adjustment, and the maximum integrated value obtained by integrating the total light emission amount at full light emission is set as the light emission reference amount. The example which controls the light emission amount of is shown. Next, FIG. 2 is an explanatory diagram when performing relative light emission to full light emission in this example. In the figure, a is the light emission waveform, that is, the output of the photometric sensor 30, and b is the integrated amount of the light emission waveform, that is, the output of the buffer amplifier 44. FIG.
In the configuration of the flash light emitting device as the light emission amount control device shown in FIG. 2, when full light emission is performed at a predetermined zoom position, the output voltage of the buffer amplifier 43 corresponding to the integrated amount becomes the voltage value Vfull shown on the right axis in FIG. The voltage of Vfull is stored in the writable storage means as the light emission reference amount when the flash light emitting device is adjusted, and when the light emission control is performed,
A voltage corresponding to the required amount of light emission for l, for example, in order to emit light of 1/16 (4 steps drop) with respect to full light emission, set the voltage of Vfull-4F as the comparator voltage, and integrate. By stopping the light emission so that the output becomes the voltage, the relative light emission with respect to the maximum light emission amount can be easily performed.

The maximum integrated amount Vfull depends on the installation position of the photometric sensor 30, but is integrated with the reflection shade,
If the reflecting plate 65 and the photometric sensor 30 move during zooming, the value should be constant at any zoom position, but in reality it changes under the influence of the reflected light from the Fresnel lens 63, so the Fresnel lens 63 changes. And the distance from the reflective shade 64 is short, that is, the maximum integration amount increases as the distance increases. Therefore, by storing the maximum integrated value for each zoom position and controlling the light emission based on the stored maximum integrated amount corresponding to each zoom position, more accurate light emission control can be performed.

Next, the basic operation of the program contained in the microcomputer 50 in this embodiment will be described with reference to FIG. [Step 101] When the power switch 52 is turned on,
The microcomputer 50 detects and initializes each port of the microcomputer 50. [Step 102] The divided voltage of the main capacitor voltage 5 input to the AD0 port is AD-converted. [Step 103] If the voltage of the main capacitor 5 is equal to or higher than a predetermined voltage at which light can be emitted, the process branches to step 104. If not, the process branches to step 105. [Step 104] Since the light emission is possible, the CHG terminal is set to Hi, the transistor 58 is turned on, a predetermined current is drawn from the terminal 57 through the resistor 61, and the light emission is transmitted to the camera. Further, the LED terminal is set to Hi, and the LED 62 is caused to emit light to indicate that light emission is possible. [Step 105] Since the light emission is disabled, the CHG terminal is set to Lo and the transistor 58 is off.
No current flows, and the camera is told that it cannot fire. Also, L
The ED terminal is set to Lo, and the LED 62 is turned off to indicate that the light emission is impossible. [Step 106] If the voltage of the main capacitor 5 read in step 102 is equal to or higher than a predetermined upper limit voltage, the process branches to step 107.
Branch to The upper limit voltage is set to a value higher than the predetermined voltage in step 103. [Step 107] The CNT terminal is set to Lo and charging is stopped. [Step 108] The CNT terminal is set to Hi and charging is started. [Step 109] The current zoom position is read from the terminals ZM0 to ZM3, and if the zoom position is set, the process branches to step 110. If not, the process branches to step 111 to drive the zoom. [Step 110] The motor drive circuit 68 is used to stop the zoom drive motor 67 when the zoom position is at a predetermined zoom position.
To the Z0 and Z1 terminals. [Step 111] When the zoom position is not in the predetermined zoom position, the current position and the set zoom position are compared, the drive direction is determined, and a predetermined signal is sent to the motor drive circuit 68 to drive the zoom drive motor 67, Z0, Output via the Z1 terminal. [Step 112] Power switch input terminal POW
When the terminal is Hi, that is, when the switch 52 is on, the process returns to step 102, and a series of processes is repeated. When Lo, that is, when the switch 52 is on off, step 1 is performed.
The process branches to step 13 to perform power-off processing. [Step 113] Perform a series of power-off processing such as charging stop, zoom driving stop, etc., set OFF terminal to high impedance state, ON terminal to Lo state, and POW terminal to WAKE UP possible state The microcomputer 50 is set to the STOP state. [Step 114] When the power switch 52 is turned on again, the POW terminal becomes Lo.
The OP state is released, initialization processing of each port is performed, and the ON terminal is set to the high impedance state.
The OFF terminal is set to the Lo state, the process returns to step 102, and the series of processes is restarted.

Next, a serial communication process performed by connecting an external connection device (not shown) to the terminals 53 to 57 of the microcomputer 50 will be described with reference to FIGS. 4 and 5. External device to CK
DI in synchronization with the serial communication clock applied to the terminal
Serial data from the external device is received at the terminal,
When a predetermined number of clocks at the CK terminal are counted, a communication interrupt occurs and the processing of FIG. 4 is performed. [Step 201] When a communication interrupt occurs, the process branches to steps 202 and 220 depending on the current communication mode, that is, whether the received data is a command or data corresponding to the command. [Step 202] The process branches depending on the received command. Note that only the necessary processing will be described here. [Step 203] When the lens focal length information reception mode from the camera is set, the communication mode is set to "data reception mode". [Step 204] The length of the focal length information is set to "communication length". [Step 205] The address of the storage area for storing the focal length information is set, the process jumps to step 213, and the communication interrupt process ends. [Step 206] In the mode in which the voltage of the main capacitor is returned to the camera, the communication mode is set to "data reception mode". In the mode in which the strobe data is transmitted to the camera, the same process as the data reception mode is performed. When the dummy data is received from the camera, the strobe return data is written in the serial data transmission buffer (not shown) of the microcomputer 50 and the serial clock CK is transmitted. In sync with the DO
Output to the camera from the terminal. [Step 207] The length of the main capacitor voltage information is set to "communication length". [Step 208] The main control voltage is written in the transmission buffer and the process jumps to step 213 to end the communication interrupt process. [Step 209] A reference luminescence amount writing process is performed. This process will be described separately. [Step 210] If the light emission amount reception mode from the camera is set, the communication mode is set to the "data reception mode". [Step 211] The length of the light emission amount information is set to "communication length". [Step 212] The address of the storage area for storing the light emission amount information is set, the process jumps to step 213, and the communication interrupt process ends. [Step 220] Communication mode "is data reception mode"
In the case of 1, the data received from the camera is read into the serial data reception buffer, stored in the predetermined address set in the command analysis mode, and if there is data to be returned from the strobe, the return data is written in the transmission buffer. [Step 221] The reception frequency counter of the reception data is incremented. [Step 222] If the received data count is equal to the communication length set in the command analysis mode, the series of command streams has ended, and the process branches to step 223. If they are not equal, the reception data still remains or the transmission data remains, and therefore the process branches to step 213 to end the communication interrupt process. [Step 223] Since the command stream has ended,
The reply mode is set to "command receiving mode" and the process jumps to step 213.

Next, the reference light emission amount writing process will be described with reference to FIG. [Step 301] The DA0 output, which is the light emission stop comparator set value, is set to the maximum value so that full light emission is performed. [Step 302] S for forcibly turning on the IGBT 16
Set the TART terminal to Hi. [Step 303] The TRI terminal is set to Hi for a predetermined time, and a light emission trigger is given to the Xe tube to emit light. [Step 304] The INT terminal is set to Lo and integration is started. [Step 305] Wait for a predetermined time until the light emission ends. [Step 306] The START terminal is returned to Lo, the IGBT gate is forcibly set to Lo, and light emission is stopped. [Step 307] The integrated light emission amount is read from the AD1 terminal. [Step 308] The INT terminal is set to Hi and the integration is completed. [Step 309] The zoom position corresponding to the current irradiation angle is read from ZM0 to ZM3. [Step 310] The write address of the EEPROM 51, which is the light emission reference amount writing means, is calculated according to the zoom position. [Step 311] The maximum integration amount, which is a light emission reference amount, is written in the EEPROM 51, which is a storage unit, according to a predetermined procedure. [Step 312] The writing process ends.

Next, referring to FIG. 7, description will be given of the light emission reference amount write adjustment performed from the outside of the flash light emitting device in the adjustment process of a factory or the like. This is performed by serial communication by an external device (not shown) through the external connection terminals 54, 55, 56. The flow in FIG. 7 is a flow in an external device. [Step 401] Following the zoom position designation command, the zoom position is transmitted to the flash light emitting device so that the flash light emitting device has a predetermined irradiation angle. [Step 402] Step 402 is looped until the zoom position is fixed at a predetermined position. The movement control of the zoom position is performed by the microcomputer 50 of the flash light emitting device. When the zoom position is moved to the zoom position communicated in step 401, the microcomputer 50 communicates and moves to step 403. [Step 403] A main condenser return command is transmitted to the flash light emitting device, and the voltage of the main condenser communicated from the microcomputer 50 is read. [Step 404] Until the main capacitor voltage reaches a predetermined voltage (full charge, the upper limit voltage), step 40
Loop 4 When the full charge voltage is reached by the communication from the microcomputer 50, the process proceeds to step 405. [Step 405] The command for performing the light emission reference amount writing process shown in FIG. 6 is transmitted. The light emission reference amount writing process is performed, and the maximum integration amount is written in the address of the EEPROM 51 corresponding to the zoom position. [Step 406] The light emission reference amount writing process ends. After that, the external device specifies each zoom position so that the operations from step 401 to step 405 are executed for each zoom position, and the above steps are repeated to write the light emission reference amount at all zoom positions. finish.

Next, the light emission control process at the time of actual photographing will be described with reference to FIG. This flow is a processing flow by the microcomputer 50. [Step 501] Connection terminals 54 to 56 for the flash light emitting device
To receive a specified light emission amount (guide number) from the outside. It goes without saying that this may be set independently by the designating means in the flash light emitting device. Thereby, the light emission amount is designated. A camera (not shown) is connected to the connection terminal. [Step 502] The X terminal 57 and the CK terminal 54 are L
When it becomes o, light emission processing is performed. To read the light emission reference amount according to the zoom position stored in the light emission reference amount storage device,
The current zoom position is read from the zoom input terminals ZM0 to ZM3, and the address of the storage device is calculated. [Step 503] According to the address obtained in step 502, the maximum integral value, which is the light emission reference amount stored in the zoom position in the EEPROM 51 as the reference light emission amount storage means, is zoomed according to a predetermined procedure as described above. Read according to the position. [Step 504] A comparator set value is calculated based on the light emission reference amount obtained in step 503 and the light emission amount instructed in step 501, and is set to the DA0 terminal which is the D / A converter output. That is, as explained in FIG.
A voltage obtained by subtracting the difference determined by the gain of the photometric circuit system and the designated light emission amount from the maximum integrated voltage Vfull at the predetermined zoom position stored in the light emission reference amount storage means is set to DA0. That is, based on the read Vfull, when the designated light emission amount in step 501 is 1/16 of the full light emission amount, Vfull-4F is set by dividing Vfull. [Step 505] S for forcibly turning on the IGBT 16
Set the TART terminal to Hi. [Step 506] The TRI terminal is set to Hi for a predetermined time and a light emission trigger is given to the Xe tube to emit light. [Step 507] The INT terminal is set to Lo and integration is started. [Step 508] When the light is emitted, the buffer amplifier 43
Integral output rises, and when it exceeds the DA0 set value, the comparator 44 is inverted, the IGBT is turned off through the AND gate 45 and the IGBT driver circuits 17 to 25, and the STOP output is generated. When STOP = Lo, the process branches to step 510, and when no STOP output is generated, the process branches to step 509. [Step 509] Even if STOP has not occurred, the time from the start of light emission is measured, and if it is less than or equal to the predetermined time, the process returns to step 508 to repeat the STOP check and the timeout check, and the STOP signal is obtained for the predetermined time due to some error. If not, the process branches to step 510 and the forced light emission is stopped. [Step 510] The START terminal is returned to Lo and the IGBT gate is forcibly set to Lo to inhibit light emission. [Step 511] The INT terminal is set to Hi and the integration is completed. [Step 512] The light emission process ends.

As described above, in the present embodiment, full light emission is performed at each zoom position during adjustment, and the maximum integrated value obtained by integrating the total light emission amount in full light emission is set as the light emission reference amount. By controlling the light emission amount during light emission, it becomes possible to easily perform the light emission amount control without the need for the variable resistance adjustment that has been widely performed in the past. In addition, the maximum integrated value is stored for each zoom position, and during light emission control, light emission control is performed based on the stored maximum integrated value corresponding to each zoom position, so that it is accurate even if the irradiation angle is changed by zooming. It is possible to perform various light emission control. Furthermore, this adjustment procedure can be easily performed without disassembling the flash light emitting device by determining a specific electric signal through a device connected to the outside of the flash light emitting device, and special adjustment of a light emitting amount measuring device or the like can be performed. It has the feature that the amount of light emission can be adjusted without a special measuring instrument.

In the above-described embodiment, the light emission amount is controlled based on the integrated value at the maximum light emission. In this case, although the relative accuracy with respect to the full light emission can be obtained, the guide of the full light emission is obtained. The number slightly fluctuates due to a capacity error of the main capacitor and an adjustment error of the upper limit voltage of the main capacitor, and an error also occurs in the guide number at each light emission amount, and the guide number also changes due to zooming. In the second embodiment,
While utilizing the features of the first embodiment, a flash light emitting device capable of setting an absolute value of a guide number is realized based on a measuring instrument capable of measuring an absolute light amount. In this case, the GN by zooming is set by setting the absolute light amount for each zoom position.
It is possible to keep o constant or to set the relative guide number ratio to the designed maximum guide number at each zoom position to be constant. Since the configuration of the flash light emitting device is the same as that of FIG. 1, description thereof will be omitted.

Next, the operation in the second embodiment will be described with reference to FIG. In this example, the integrated value at a predetermined absolute value guide number lower than full light emission is stored as the light emission reference amount in the light emission reference amount storage means, and light emission control is performed so that the absolute value of the guide number cannot be obtained during shooting. As an example, at the time of adjustment, when the absolute light intensity value about one step below full emission is reached, a latch signal is generated from the outside, the microcomputer 50 of the flash emission device reads the integrated emission amount, and the emission reference amount storage device To memorize. At the time of light emission, light emission control is performed based on a light emission reference amount whose absolute value is guaranteed. Since the basic operation of the flash light emitting device is the same as that of the first embodiment shown in FIGS. 2 to 8, the description thereof will be omitted and only the differences will be described.

First, the reference light emission amount writing process will be described with reference to FIG. [Step 601] The DA0 output, which is the light emission stop comparator set value, is set to the maximum value, and the full light emission is set. [Step 602] S for forcibly turning on the IGBT 16
Set the TART terminal to Hi. [Step 603] The TRI terminal is set to Hi for a predetermined time, and a light emission trigger is given to the Xe tube to emit light. [Step 604] The INT terminal is set to Lo and integration is started. [Step 605] When a predetermined light amount (or just before the predetermined light amount in consideration of delay) is reached in the light amount estimation device outside the flash light emitting device, the connection terminal (in this embodiment, C
The step 605 is looped until the write signal issued from the (K terminal) is received, and when the write signal is received, the process branches to the step 606. [Step 606] The integrated emission amount is read from the AD1 terminal. [Step 607] The START terminal is returned to Lo, the IGBT gate is forcibly set to Lo, and light emission is stopped. [Step 608] The INT terminal is set to Hi and the integration is completed. [Step 609] The zoom position corresponding to the current irradiation angle is read from ZM0 to ZM3. [Step 610] The write address of the EEPROM 51, which is the light emission reference amount writing means, is calculated according to the zoom position. [Step 611] A reference integration amount, which is a light emission reference amount, is written in the EEPROM 51, which is a storage unit, according to a predetermined procedure. [Step 612] The writing process ends.

Next, referring to FIG. 11, description will be given of the light emission reference amount write adjustment performed from the outside of the flash light emitting device in the adjustment process of a factory or the like. This is performed by serial communication with an external device through the external connection terminals 54, 55, 56. [Step 701] Following the zoom position designation command, the zoom position is transmitted to the flash light emitting device so that the flash light emitting device has a predetermined irradiation angle. [Step 702] The step 702 is looped until the zoom position is fixed at a predetermined position. [Step 703] A main capacitor return command is transmitted to the flash light emitting device to read the main capacitor voltage. [Step 704] Step 704 is looped until the main capacitor voltage reaches a predetermined voltage. [Step 705] When the main capacitor reaches the predetermined voltage, the command for starting the light emission reference amount writing process shown in FIG. 10 is transmitted to start the light emission reference amount writing process. Steps 701 to 705 are steps 401 to 405.
Is the same as [Step 706] The amount of light emission is measured by a light amount measuring device outside the flash light emitting device, and step 706 is looped until a predetermined amount of light is reached, and if reached, the process branches to step 707. That is, the microcomputer 50 that has transmitted the write start command in step 705 starts the processing of FIG. 10 and the flash light is emitted. This flash light emission is detected by an external measuring device, and when the integration of the flash light reaches a predetermined value, the process proceeds to step 707. [Step 707] The CK terminal is set to Hi, and the light emission reference amount write signal is transmitted. As a result, the microcomputer 50 executes steps 606 to 612 in FIG. 10 and writes the light emission integral serving as the reference in the EEPRON address corresponding to the designated zoom position. [Step 708] The light emission reference amount writing process is ended, but the light emission reference amount writing at all zoom positions is completed by executing the operations from step 701 to step 707 at each zoom position.

Next, the light emission control process at the time of actual photographing will be described with reference to FIG. [Step 801] Connection terminals 54 to 56 for the flash light emitting device
To receive the designated light emission amount. Needless to say, this may be set independently in the flash light emitting device. It should be noted that this flow is performed with the camera connected to the flash light emitting device. [Step 802] The X terminal 57 and the CK terminal 54 are set to L
When it becomes o, light emission processing is performed. To read the light emission reference amount according to the zoom position stored in the light emission reference amount storage device,
The zoom position is read from the zoom input terminals ZM0 to ZM3, and the address of the storage device is calculated. [Step 803] According to the address obtained in step 802, the light emission reference amount corresponding to the zoom position is read from the EEPROM 51, which is the reference light emission amount storage means, according to a predetermined procedure. [Step 804] The comparator set value is calculated based on the light emission reference amount obtained in step 803 and the light emission amount instructed in step 801, and is set to the DA0 terminal which is the D / A converter output. That is, as explained in FIG.
If the light emission amount is darker than the reference light emission amount, the reference light emission amount integrated voltage at the predetermined zoom position stored in the light emission reference amount storage means.
The voltage obtained by subtracting the difference determined by the gain of the photometric circuit system and the designated light emission amount from Vref is set to DA0, and when the light emission amount is brighter than the reference light emission amount, the predetermined zoom stored in the light emission reference amount storage means is set. A voltage obtained by adding the gain of the photometric circuit system and the difference determined by the designated light emission amount is set to DA0 from the reference light emission integrated voltage Vref at the position. Incidentally, in detail, it is the same as the processing of step 504, and when the reference light emission amount is one step lower than Vref, the voltage corresponding to −2F is set. [Step 805] S for forcibly turning on the IGBT 16
Set the TART terminal to Hi. [Step 806] The TRI terminal is set to Hi for a predetermined time and a light emission trigger is given to the Xe tube to emit light. [Step 807] The INT terminal is set to Lo and integration is started. [Step 808] When the light is emitted, the buffer amplifier 44
The integrated output of rises, and when it exceeds the set value of DA0, the comparator 44 is inverted and the AND gate 45, IG
The IGBT is turned off and the STOP output is generated through the BT driver circuits 17 to 25. Ie ST
When OP = Lo, the process branches to step 810 and STOP
If no output is generated, the process branches to step 809. [Step 809] The time from the start of light emission is measured even if STOP has not occurred, and if it is less than the predetermined time, step 80
Return to step 8 and repeat the STOP check and the timeout check, and due to some error, STO for the predetermined time
If no P signal is obtained, branch to step 810,
The forced flash is stopped. [Step 810] The START terminal is returned to Lo and the IGBT gate is forcibly set to Lo to inhibit light emission. [Step 811] The INT terminal is set to Hi and the integration is completed. [Step 812] The light emission process is terminated.

As described above, in the second embodiment, the absolute reference light emission amount is stored at each zoom position at the time of adjustment, and the integrated value of the absolute light amount is used as the light emission reference amount. By controlling the light emission amount based on the difference, it is possible to perform the light emission amount control in which the absolute value is guaranteed.

In the second embodiment, the reflection plate 65 for receiving the light of the Xe tube and the light receiving sensor 30 are located in the fixed portion integrated with the reflection shade 64, so that the light emission is performed with a constant guide number. For this purpose, it is necessary to store the light emission reference amount for each zoom position.
When is attached to a fixed portion integrated with the Fresnel lens 63, since light is received almost equivalently to the subject side, if one reference light emission amount is stored regardless of the zoom position, fluctuation of the guide number due to zooming will occur. It is possible to obtain a flash device that is held down. An embodiment in this case will be described. Since the configuration of the flash light emitting device is the same as that of FIG. 1, the description is omitted.

First, the reference light emission amount writing process in this embodiment will be described with reference to FIG. [Step 901] The DA0 output, which is the light emission stop comparator set value, is set to the maximum value so that full light emission is performed. [Step 902] S for turning on the IGBT 16 forcibly
Set the TART terminal to Hi. [Step 903] The TRI terminal is set to Hi for a predetermined time, and a light emission trigger is given to the Xe tube to emit light. [Step 904] The INT terminal is set to Lo and integration is started. [Step 905] When a predetermined amount of light (or just before the predetermined amount of light in consideration of delay) is reached by a light amount measuring device outside the flash light emitting device, an external connection terminal (in this embodiment, C
The step 905 is looped until the write signal issued from the (K terminal) is received, and the step 906 is branched when the write signal is received. [Step 906] The integrated light emission amount is read from the AD1 terminal. [Step 907] The START terminal is returned to Lo, the IGBT gate is forcibly set to Lo, and light emission is stopped. [Step 908] The INT terminal is set to Hi and the integration is completed. [Step 909] A reference integration amount, which is a light emission reference amount, is written in the EEPROM 51, which is a storage unit, according to a predetermined procedure. [Step 910] The writing process ends.

Next, the light emission reference amount write adjustment will be described with reference to FIG. [Step 1001] The zoom position is transmitted to the flash light emitting device following the zoom position designation command so that the flash light emitting device has a predetermined irradiation angle. [Step 1002] Step 1002 is looped until the zoom position is fixed at a predetermined position. [Step 1003] A main capacitor return command is transmitted to the flash light emitting device to read the main capacitor voltage. [Step 1004] Step 1004 is looped until the main capacitor voltage reaches a predetermined voltage. [Step 1005] When the main capacitor reaches the predetermined voltage, the command for starting the light emission reference amount writing process shown in FIG. 13 is transmitted to start the light emission reference amount writing process. [Step 1006] The amount of emitted light is measured by a light amount measuring device external to the flash light emitting device, and step 1006 is looped until a predetermined amount of light is reached, and if reached, step 1007
Branch to [Step 1007] The CK terminal is set to Hi, and the light emission reference amount write signal is transmitted. [Step 1008] The light emission reference amount writing process ends. This flow is the same as the flow shown in FIG.

Next, the light emission control process at the time of actual photographing will be described with reference to FIG. This flow is performed with the camera connected to the flash light emitting device. [Step 1101] Connecting terminals 54 to 5 to the flash light emitting device
The light emission amount is transmitted through 6. Needless to say, this may be set independently in the flash light emitting device. [Step 1102] When the X terminal 57 and the CK terminal 54 become Lo, light emission processing is performed. The light emission reference amount stored in the EEPROM 51 serving as the light emission reference amount storage means is read. [Step 1103] A comparator set value is calculated based on the light emission reference amount obtained in step 1102 and the light emission amount instructed in step 1101 and set to the DA0 terminal which is the D / A converter output. That is, as described with reference to FIG. 9, when the light emission amount is darker than the reference light emission amount, the gain of the photometric circuit system is specified from the reference light emission amount integrated voltage Vref at the predetermined zoom position stored in the light emission reference amount storage means. The voltage obtained by subtracting the difference determined by the light emission amount is set to DA0, and when the light emission amount is brighter than the reference light emission amount, the reference light emission integrated voltage Vr at the predetermined zoom position stored in the light emission reference amount storage means.
From ef, the voltage obtained by adding the gain of the photometric circuit system and the difference determined by the designated light emission amount is set to DA0. [Step 1104] The START terminal is set to Hi in order to forcibly turn on the IGBT 16. [Step 1105] The TRI terminal is set to Hi for a predetermined time and a light emission trigger is given to the Xe tube to emit light. [Step 1106] The INT terminal is set to Lo and integration is started. [Step 1107] Buffer amplifier 4 with light emission
The integrated output of 4 rises, and when the DA0 set value is exceeded, the comparator 44 is inverted and the AND gate 45, the IGBT
The IGBT is turned off and the STOP output is generated via the driver circuits 17 to 25. That is, STOP
= Lo, the process branches to step 1109, and while STOP has not occurred, the process branches to step 1108. [Step 1108] The time from the start of light emission is measured even if STOP has not occurred, and if it is less than the predetermined time, step 1
Return to 107 and repeat STOP check and timeout check.
If the TOP signal cannot be obtained, the process branches to step 1109 to forcibly prohibit the light emission. [Step 1109] Return the START terminal to Lo,
The IGBT gate is forcibly set to Lo to stop light emission. [Step 1110] The INT terminal is set to Hi and the integration is completed. [Step 1111] The light emission process ends.

As described above, in the third embodiment, the light receiving sensor is arranged at a position equivalent to the subject side to suppress the change of the guide number due to zooming, and thus one light emission amount reference value is used as a basis. It is possible to control the amount of light emission whose absolute value is guaranteed.

[0030]

As described above, according to claims 1 to 5,
Reference data corresponding to a predetermined guide number is stored in the storage means, and the light emission amount data is formed on the basis of this data at the time of photographing, so that adjustment of the light emission amount in the factory is simplified and accurate light emission amount control means is provided. Can be realized. Further, in the sixth aspect, since the reference data is stored corresponding to the zoom position, it is possible to realize accurate light emission amount control even if the zoom position changes.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an example of an embodiment of a light emission amount control device according to the present invention.

FIG. 2 is a waveform diagram for explaining the operation of the embodiment example shown in FIG.

FIG. 3 is a flowchart illustrating the overall operation of FIG.

FIG. 4 is a flowchart for explaining communication interrupt processing in the circuit diagram shown in FIG.

FIG. 5 is a flowchart for explaining communication interrupt processing together with FIG.

FIG. 6 is a flowchart for explaining a light emission reference amount writing process in the circuit diagram shown in FIG.

FIG. 7 is a flowchart for explaining a light emission reference amount writing process together with FIG.

8 is a flow chart for explaining a light emission control operation in the circuit diagram of FIG. 1. FIG.

FIG. 9 is a waveform diagram for explaining the operation of the second exemplary embodiment of the present invention.

FIG. 10 is a flow chart for explaining a light emission reference amount writing process in the second embodiment of the present invention.

FIG. 11 is a flowchart for explaining a light emission reference amount writing operation with FIG. 10.

FIG. 12 is a flow chart for explaining a light emission control operation in the second embodiment.

FIG. 13 is a flowchart for explaining a light emission reference amount writing process in the third embodiment of the present invention.

FIG. 14 is a flowchart for explaining a light emission reference amount writing operation together with FIG.

FIG. 15 is a flowchart illustrating a light emission control operation according to the third embodiment.

FIG. 16 is a circuit diagram showing a configuration of a conventional flash device.

[Explanation of symbols]

 1 ... Battery 2 ... DC / DC converter 5 ... Main capacitor 6 ... Thyristor 11 ... Xe tube 12 ... IGBT 30 ... Photometric sensor 50 ... Microcomputer 51 ... EEPROM

Claims (6)

[Claims] 1. A capacitor for storing a flash charge,
Light emitting means for emitting flash light by discharging the electric charge of the capacitor, light emission amount data setting means for setting light emission amount data by the light emitting means, and light emission at the time of photographing based on the data set by the setting means And a light emission amount control means for controlling the light emission amount by means, and depending on the integrated value of the light receiving output by the light emitting means for flash light emission when the flash light emission is performed by the light emitting means with the capacitor charged to a predetermined voltage. And a processing unit for setting the light emission amount data to the light emission amount data setting unit based on the reference data of the storage unit. Control device 2. A capacitor for accumulating a flash charge,
Light emitting means for emitting flash light by discharging the electric charge of the capacitor, light emission amount data setting means for setting light emission amount data by the light emitting means, light receiving means for directly receiving flash light emission by the light emitting means, The light emitting means includes an integrating means for integrating the output of the light receiving means, and a light emitting quantity control means for stopping the light emission by the light emitting means when the output of the integrating means reaches a value according to the light emitting quantity data. A storage unit that measures the amount of light emitted when a flash light is emitted by an external photometric device, and stores the output of the integration unit when the amount of emitted light reaches a predetermined value as reference data; A light emission amount control device provided with processing means for setting the light emission amount data in the light emission amount data setting means based on the reference data of the storage means. 3. The reference data is stored in advance in the storage means in an adjustment process in a factory or the like.
2. Light emission amount control device according to 2. 4. A designation means for designating a light emission amount is provided,
2. The processing means divides the reference data according to the designated light emission amount to form light emission amount data.
The light emission amount control device according to any one of claims 1 to 3. 5. The light emission amount control means stops the flash light emission when the integrated value of the output by the photometric means becomes a value according to the data set by the setting means. Light emission control device 6. A light emission characteristic adjusting means for adjusting light emission characteristics is provided by changing the distance between the Fresnel lens provided on the front surface of the light emitting means and the light emitting means at a plurality of predetermined intervals. A plurality of the reference data obtained respectively in a state in which the distance between the Fresnel lens and the light emitting means is changed are stored in the storage means, and at the time of photographing, the processing means sets the reference according to the distance between the Fresnel lens and the light emitting means. The light emission amount control device according to claim 1, wherein data is selected and light emission amount data is formed based on the selected reference data.