JPS63199334A - Electronic flashing device - Google Patents

Abstract

PURPOSE:To attain repeated light emission of plural times only by one releasing operation by forming a signal line in addition to a signal line for an X contact, and starting light emission when both the two signal lines are turned to light emission enable states. CONSTITUTION:When the X contact is closed, an X terminal is turned to L0. When repeated light emission is selected by a selecting means, a CPU 5 turns an output terminal RP for repeated light emission to H1 after starting light emission. Consequently, a NOR circuit 2 outputs L0 and the clock input terminal of a D-FF 3 is turned to L0. When the time set up by a light emission interval is elapsed, the CPU 5 turns the terminal RP to L0 again and the circuit 2 outputs an H1 signal to emit a xenon tube Xe again. The CPU 5 repeats said operation by the number of times of repeated light emission to repeatedly emit the xenon tube Xe by the set number of times.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to repeated light emission of an electronic flash device (hereinafter referred to as a strobe).

[Conventional technology]

Normally, a strobe flashes when the X contact is closed. fJX
Light emission starts at the edge where the voltage of the contact line changes from a high level "H1" to a low level "LO". Furthermore, since the camera closes the X contact while the shutter is fully open, the X contact is closed only once in one release. From the above, the strobe fires only once when the camera is released once.

On the other hand, there is a photography method called decomposition photography in scientific photography. This photo is a multiple exposure of the subject's movement intermittently, and the shooting method is to leave the shutter of the camera open for a long time in the dark, and then fire the strobe several times intermittently during that time. There is something called letting. However, as mentioned above, the strobe fires only once with each release, so it is not possible to take such a disassembled photo using the normal method, so the camera and strobe are separated and the strobe fires independently. I had to have it.

[Problem that the invention seeks to solve]

In the conventional technology as described above, in order to take a disassembly photograph, a camera and a strobe must be installed and operated separately, which has the problem of complicating the photographing process. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to obtain a strobe that is linked to a camera and that can repeatedly emit light a plurality of times with a single release.

[Means for solving problems]

In order to solve the above problems, the present invention provides another signal line in addition to the signal line of the X contact, and is configured to start emitting light when the other signal line becomes capable of emitting light.

[For production]

In the present invention, another signal line is provided in addition to the X contact line for the strobe light emission start signal, and further,
Since it starts emitting light as a result of logical operation of two signals,
Even when the X contact is closed, a command to start light emission can be issued multiple times, and light emission can be performed multiple times during one release.

〔Example〕

FIG. 1 shows a first embodiment of the invention.

The negative side of power supply E is connected to ground line l. The positive side of the power source E is connected to one side of the power switch SWI. The other side of the power switch SW1 is connected to the power line 12, and the other side of the power switch SW1 is connected to the power line 12.
When I turns on, power is supplied to the circuit. The booster circuit 1 is
The power supplied from the power line ρ2 is boosted and output to the main capacitor C1 via the diode D1. This output is also output to trigger capacitor C2 via resistor R1, commutation capacitor C6 via resistors R6 and R4, and capacitor C7 via resistors R7 and R8.

One end of the primary side of the trigger transformer T is connected to the connection point between the trigger capacitor C2 and the resistor R1, and the other end is connected to the anode of the trigger thyristor 5CRI.

One end of the secondary side of the trigger transformer is connected to the cathode of the xenon tube Xe, and the other end is connected to a trigger hand provided at the center of the xenon tube Xe.

The anode of the xenon tube Xe is connected to the main capacitor C.
It is connected to the connection point between I and the diode DI, and its cathode is connected to the anode of the main thyristor 5CR2 and the connection point between the commutating capacitor C6 and the resistor R4 in addition to the secondary side of the trigger transformer. The resistor R7 has one end connected to the connection point between the main capacitor CI and the diode DI, and the other end connected to the resistor R8 and the transistor Tr.

connected to the base of. The other end of resistor R8 is connected to the emitter of transistor Tr+ and capacitor C7.

One end of resistor R6 is connected to main capacitor C1 and diode D.
The other end is connected to the commutating capacitor C6 and the commutating thyristor 5CR3.

The cathodes of the three Cyrisks 5CRI, 5CR2, and 5CR3 are connected to the ground line β, respectively, and noise removal capacitors C3, C4, and C5 are connected between the gates and the cathodes, respectively.

Trigger thyristor 5CRI and main thyristor 5CR
In addition to the capacitor, resistors R2 and R2 are connected to the gates of R2 and R2, respectively.
R3 is connected, and the other end of this resistor is also connected to D.
It is connected to the output Q of flip-flop 3.

In addition to the capacitor, a resistor R5 is connected to the gate of the commutating circuit 5CR3, and the output of the comparator 4 is connected to the other end of the resistor.

A resistor R9 is connected to the collector of the transistor Tr+, and the other end of the resistor is connected to the cathode of the Zener diode D4, the resistor R13, and the recent terminal R of the D flip-flop 3. Also, the anode of Zener diode D4 is the ground line! ,It is connected to the.

The other end of the resistor R13 is connected to the resistor R12 and the base of the transistor Trz, and the other end of the resistor R12 and the emitter of the transistor Trz are connected to the ground line II. The collector of the transistor Trz is connected to the resistor R14, the resistor R15, and the base of the transistor Tr3. The other end of the resistor R14 is connected to the power supply line β2, and the other end of the resistor R15 and the emitter of the transistor Tr3 are connected to the ground line 11. , the collector of the transistor Tr3 is connected to the integrating capacitor C8, the input terminal of the comparator 4, and the anode of the light receiving element D3, respectively.

The light receiving element D3 is provided at a position where it can receive light emitted from the xenon tube Xe, and its cathode is connected to the power line j22.
It is connected to the. One input terminal of comparator 4 has
The other end is connected to a resistor R15 connected to the power supply line 12, and also connected to resistors R17, R18, RI9, and R20.

Resistors R17, R18, R19, and R20 are connected to output terminals FO, Fl, F2, and F3 of cpU5, respectively.

In addition, the CPU 5 has an output terminal RP for repetitive light emission.
One of the two inputs of the OR circuit 2 is an input terminal INT, which is an X contact signal input terminal and also a program interrupt control terminal, and the other input of the NOR circuit 2 is connected to the power supply line 7. An input terminal IN for monitoring the connection relationship of the external power connector is connected to the pull-amp resistor RIO connected to !2 and the X contact terminal connected to the camera, and the pull-up resistor R22 whose other end is connected to the power supply line β2 and , a pull-up resistor R21 whose other end is connected to one terminal of the external power switch SW2 is a switch input terminal 5WIN for switching the amount of light emitted and connected to the power supply line β2.
and one terminal of the light emission amount changeover switch SW3. Note that the other terminals of SW2 and SW3 are each connected to the ground line III.

The output of the NOR circuit 2 is connected to the clock input terminal CLK of the D flip-flop 3.

The data input terminal of the D flip-flop 3 is connected to a pull-up resistor R11 whose other end is connected to the power supply line 12. Although not shown, the NOR circuit 2,
The power terminals of the D flip-flop 3, the comparator 4, and the CPU 5 are connected to the power line β2, and the ground terminals are connected to the ground line IlI. Also, CPU5
includes a display device (for example, a liquid crystal display element or LC) (not shown).
A display device such as D) is connected to control various displays. In addition, various input means (not shown) (selection of repeated light emission, means for inputting the number of repeated light emission, etc.) are also connected.

Also, the strobe has a connection terminal for an external device.
− I have it. Among these, an X terminal that is connected to the X contact of the camera as a terminal for making an electrical connection with the camera;
and connected to the camera ground.

V that has a 0NDI terminal and is connected to an external power supply that outputs the same output as the booster circuit l, and is connected to the output of the external power supply device to the external power supply connector 6 to shorten the charging time of the main capacitor C1. It has a GND2 terminal connected to Ce□ and the same ground.

This vccll terminal is connected to the connection point between the main capacitor C1 and the diode D1 via the diode D2,
Power from an external power source is supplied to the main capacitor ci.

In addition, when the external power supply device is connected, the external power supply connector closes and indicates that the external power supply device is connected.
An external power switch SW2 is provided to turn the power on.

When the power switch SWI is closed, the power line 7!2
Power is supplied to each circuit. The booster circuit 1 thereby boosts the power supply voltage and outputs its output to the main capacitor C1, trigger capacitor C2, commutating capacitor C6, and capacitor C7 to charge these capacitors.

On the other hand, the X terminal and GND1 terminal are connected to the X contact and ground of the camera (not shown), but when the camera is not in the release state, the connection between X and GNDI is open, so the two terminals of NOR circuit 2 One of the inputs is pulled up to the power supply voltage by a pull-up resistor RIO (hereinafter referred to as "H"). Therefore, the output of the NOR circuit 2, that is, the clock input terminal C of the D flip-flop 3
LK is always at the ground potential (hereinafter referred to as "LO"), and the output Q of the D flip-flop 3 becomes "LO". As a result, the trigger thyristor 5CRI and the main thyristor 5CR2 are turned OFF, and the xenon tube Xe does not emit light. When Xe does not emit light, the output of the booster circuit I is output from the resistor R7 to the resistor R8 and the capacitor C7, so that the base and emitter of the transistor Trl are reverse biased, and T r + is turned off.

Therefore, the reset terminal of the D flip-flop 3 is "
LO'', and the D flip-flop 3 is in a normal operating state without being reset.
Since the current is 0FFf, no base current is supplied to the transistor Trz, and Tr2 is turned off. Trz is O
When the transistor Tr+ is FF, the base current is supplied by the resistor R14 and the transistor Tr+ is turned ON. When Try is ON, the integrating capacitor C8 becomes "LO" and all accumulated charges are discharged. Further, the photocurrent from the light receiving element D3 is also completely bypassed.

In this state, when a camera (not shown) is released and the shutter is fully opened, the X contact is closed. As a result, the X terminal becomes "LO". When the X terminal becomes "LO", one of the two input terminals of the NOR circuit 2 connected thereto and the interrupt input terminal INT of the CPU 5 become "LO".
become. The interrupt input terminal INT of the CPU5 is “LO”
This causes the program to move to the interrupt control routine described later. At this time, when the output of the output terminal RP for repetitive light emission of the CPU 5 is "LO", both the two inputs of the NOR circuit 2 become "LO", and the output and the clock input terminal CLK of the D flip-flop 3 change from "LO" to "LO". It becomes “HL”. The D flip-flop 3 inputs data when CLK changes from "LO" to "H1", that is, at the "Hl" edge trigger, and outputs the value. In this case, the data input terminal is connected to the pull-up resistor R11. Always “HI”
”, output Q is “HI”.

When the output of the D flip-flop becomes “Hl”, the resistance R
2 to the gate of the trigger thyristor 5CRI, and via the resistor R3 to the gate of the main thyristor 5CR2.
A gate current is supplied to each, and both are turned on. When trigger thyristor 5CRI turns on, trigger capacitor C
2 flows to the trigger cyrisk 5CRI via the primary side of the trigger transformer T. Therefore, a high voltage is generated on the secondary side of the trigger transformer T, a trigger is applied to the xenon tube Xe, and the discharge light of Xe is started. When discharge is started, the charge of the capacitor C7 is discharged to the resistors R8, R7, Xe, and the main thyristor 5CR2, and the transistor Tr is turned on. Tr+ is ON
Then, a voltage is generated across the resistor R9 and the Zener diode D4. The Zener diode D4 makes this voltage a constant voltage, and the resistor R4 and the reset terminal R of the D flip-flop 3
supply to. D flip-flop 3 has a reset terminal R
It is reset when becomes “HI”, and the output Q becomes aL.
In other words, the D flip-flop 3 outputs Q from the light emission start command (in this case, X becomes "LO") until the xenon tube Xe actually starts emitting light.
Hl”, trigger, main Zyristor 5CRI,
Turn on 5CR2.

On the other hand, the transistor Tr2 short-circuits between the ONL, the base and the emitter of the transistor Tr3, and turns off the transistor Tr3 due to the voltage being supplied to the resistor R13.

Further, by turning off the transistor Tr3, the integrating capacitor C8 can be charged.

The light receiving element D3 receives the light emitted from the xenon tube Xe, converts it into a current, outputs this photocurrent to an integrating capacitor C8, and the integrating capacitor C8 charges the photocurrent.

On the other hand, the CPU 5 has a light emission amount switching switch input terminal 5.
Depending on the input state of WIN, the amount of light emission is determined according to a flowchart described later, and is output to output terminals FO to F3. This output is output so that the selected terminal becomes "LO" and the other terminals become high impedance. As a result, the single power terminal of the comparator 4 connects the power supply voltage to the resistor R
15 and a resistor selected from resistors R17 to R20.

The xenon tube Xe emits light, and the photocurrent photoelectrically converted by the light receiving element D3 is applied to the integrating capacitor C8, and when the charging voltage of this C8 exceeds the voltage of the comparator 4 alone, the output of the comparator 4 becomes "Hl". This output is resistor R
5 to the gate of commutating thyristor 5CR3, and 5CR3 is turned on. When 5CR3 is turned on, the main thyristor 5CR2 is reverse biased by the electric charge charged in the commutating capacitor C6, and 5CR2 is turned off to stop emitting light.

Further, from this, it can be seen that in order to change the amount of light emitted by the strobe, it is sufficient to change the voltage of the comparator 4 alone. For example, to increase the amount of light emitted by one step (double the amount of light), the - input terminal should be doubled.

When resistor R17 is selected, the amount of light emission is the lowest and R18
, R19, and R20, R17, R18, R19, and R20 can be determined from the following equations.

8xR174xR18 2xR19R20 R19+R15R20+R15 Also, without selecting all the resistors from R17 to R20,
When all of the output terminals FO to F3 are set to high impedance, the single input terminal of the comparator 4 is pulled up to the power supply voltage, so that the strobe emits light at full intensity.

The external power connector 6 connects the main capacitor C1 from the outside.
This is a connector for supplying power to the device, and an external power switch SW2 is provided inside.

Normally, when no external power supply device is connected to the external power connector, the external power switch SW2 remains open, and the main capacitor CI is charged only by the booster circuit 1.

When an external power supply device is connected to the external power connector 6, S
W2 is closed, the input terminal TN that monitors the connection relationship of the external power connector of CPU6 becomes "LO", and the
Notifies U5 that the external power supply is connected. Also, V
cc) Power is supplied from the outside to the main capacitor C1 from the I terminal via the diode D2, and as a result, the main capacitor C1 is charged by both the booster circuit 1 and the external power supply device, so the charging time is shortened. .

On the other hand, when repeated light emission is selected by the selection means (not shown), the CPU 5 connects the output terminal RP for repeated light emission after the start of light emission.
Set to “Hl”. As a result, the NOR circuit 2 outputs "LO" because one of the two inputs becomes "HT", and the clock input terminal CL of the D flip-flop 3 outputs "LO".
K becomes “LO”. After that, when the CPU 5 sets RP to "LO" again, the NOR circuit 2 has two inputs "L".
O'', so it outputs "HI", and the D flip-flop 3 again outputs H1'' to the output Q, causing the xenon tube to emit light again.

The CPU 5 repeats the above process for the number of repeated luminophores inputted by an input means (not shown), and causes the xenon tube Xe to emit light repeatedly a set number of times.

The operation of the CPU will be explained below with reference to the flowchart. FIGS. 2(A), 2(B), 2(C), and 2(D) are flowcharts for setting various data of the strobe, and are normal routines for performing normal control. The power is turned on in step S1, and the light emission mode is read in step S2 (for example, repeat light emission mode, normal light emission mode, etc.)
Do the following.

Next, in step S3, the flash light amount changeover switch SW'3 is checked. If this switch is open, a switch flag (1) indicating that the switch is OFF is set in step S4, and the process proceeds to step S8. Further, if the switch SW3 is ONI, the process advances to step S5 and the switch flag (1) is confirmed.

At this time, if the switch flag (1) is cleared, the process proceeds to step S8 in the same way as when the switch SW3 is OFF.

If the switch flag (1) is set in step S5, the process advances to steps S6 and S7, and the switch flag (1) is set.
1) Clear the memory RAM for flash output setting.
Add 1 to (1) and proceed to step S8.

That is, in steps 83 to S7, switch SW3 is set to OFF.
When it is FF, it is recorded that the switch SW3 is OFF by setting the switch flag (1) without adding 1 to RAM (1).

When switch SW3 is ON, switch flag (1)
The state of the previous switch SW3 is confirmed by
) plus 1.

In step S8, it is checked whether the value of RAM (1) has become 2 or more. If the value of RAM (1) is less than 2, the process advances to step S14 and the amount of light emitted by the strobe is set.

If the value of RAM (1) is 2 or more, the process advances to step S9, and it is confirmed by the 5WIN input whether the external power supply device is connected. If the external power supply device is connected, the process advances to step S12 and the RAM (1
) is 5 or more. As a result, RAM
If (1) is less than 5, the process proceeds to step 314; if it is 5 or more, RAM (1) is set to 0 and the process proceeds to step S14. If the external power supply device is not connected in step S9, the process proceeds to step S10, and the light emission mode is confirmed. If the light emission mode is not the repeat light emission mode, the process proceeds to step S12, and if RAM (1) is 5 or more as described above, RAM (1) is set to O and the process proceeds to step SI4. If the light emission mode is the repeat light emission mode, RAM (1) is set to O in step 311 and step S
Proceed to step 14.

In steps 314 to S17, the value of RAM (1) is confirmed, and depending on the value, the process proceeds to any one of steps 319 to S23, and the output terminals FO to F3 for setting the light emission amount are set.

In this embodiment, the relationship between the value of RAM (1), the amount of light emission, and the output terminals FO to F3 is shown in FIG. That is, in steps 88 to S14, the following operations are performed.

First, check whether the value in the memory RAM (1) for setting the light intensity is a value that indicates 1/16 or 1/8 of the maximum light intensity, and if it is 1/16.1/8, set the light intensity as is. do. In step S9, SIO, it is determined whether setting of 1/4 light amount or more is possible.

When a strobe flashes repeatedly using only its built-in battery, if the amount of light emitted per time is large (a large amount of energy charged in the main capacitor C1 is consumed per flash), Since the main capacitor CI cannot be sufficiently charged until the next light emission, repeated light emission cannot be performed. Normally, a certain number of repeated flashes can be obtained with 1
This is a case where light is emitted at a light intensity of /8 or less, and the number of times of light emission is obtained 4 times with a light intensity of 1/8 and 8 times with a light intensity of 1/16.

However, if the main capacitor C1 is charged externally, the charging capacity will increase, and a considerable amount of charging can be done between the flashes, so even if the amount of flash is large at one time, repeated flashes are possible. be.

From the above, in step S9, the connection status of the external power source is checked, and if the external power source is connected, it is possible to select repeated light emission with a large amount of light emission.

Further, in step SIO, the light emission mode is checked, and if the light emission is not repeated, light emission with a large amount of light emission is possible.

After FO-F3 is set in steps 319 to S23,
It is checked whether the light emission mode proceeding to step 324 is a repeat light emission mode. If it is not the repeat light emission mode, the process advances to step S25 by -20= and the value of RAM (2) in the memory is set to 1.

Memory RAM (2) is a memory for the number of times the light is repeatedly emitted, and the light is emitted by the memory value.

In other words, when the value of RAM (2) is 1, the light is not emitted repeatedly, but only once. In this embodiment, when the value of RAM (2) is 0, light emission is repeated indefinitely while the X contact is closed.

If the light emission mode is the repeat light emission mode, the process advances to step 326. Steps S26 to 830 are performed when the previous light emission count input switch was OFF and this time it is ON, as in steps 83 to S7, that is, when the switch is OFF.
When changing from FF to ON, RAM (2) is incremented by 1. Incidentally, although not shown, the luminophoric unit has the same configuration as the light emission amount changeover switch SW3, and the light emission amount is changed by this switch.

Next, the process advances to step S31, and the amount of emitted light is confirmed. Here, if the amount of emitted light is 1/8 of the total amount of light, the process proceeds to step S32, and if not, the process proceeds to step 838.

In step S32, the number of times of light emission at ⅛ light intensity is checked. With ⅛ light intensity, it is possible to repeatedly emit light up to four times as described above, so if the number of times of light emission is four or less, the number of times of light emission is set as is, and the process proceeds to step S44.

If the number of times of light emission is set to five or more, the process advances to step S33, and the connection status of the external power supply device is checked.

As mentioned earlier, the built-in battery alone has a low charging capacity for the main capacitor C1, so in the case of repeated flashes, the main capacitor cannot be sufficiently charged between flashes, so there are limitations as described above. . However, if you connect an external power supply, the charging capacity of the main capacitor increases and the main capacitor can be charged a considerable amount between flashes, so there is no need to limit the number of flashes. Can emit light repeatedly.

For the above reasons, in step S33, the connection status of the external power source is checked, and if the external power source is not connected, the number of repeated flashes is limited, and the number of flashes in RAM (2) is set to 1.
Make it. If an external power source is connected, step S3
Proceed to step 5 and set the value of RAM (2) to O. Furthermore, RAM
When the value of (2) is 0, there is no limit to the number of times of repeated light emission.

If the amount of emitted light is other than 1/8 in step S31, the process advances to step 338, and the number of repeated light emission is counted from step 338 to step S41 in the same manner as steps 332 to S35.

In step 344, a signal from a light emission prohibition input means (not shown) is read. The manual flash prohibition means outputs a signal when the photographer intentionally prohibits the strobe from emitting light, or when the photographer wants to prohibit the strobe from being emitted due to the shooting conditions of the camera or strobe.

In step 345, it is determined whether or not light emission is prohibited;
If the light emission is prohibited, the process advances to step S46, where the light emission prohibition flag is set and the output i-response for repeated light emission is set to "HI".
Then, the process advances to steps S48 and S49.

If light emission is not prohibited, the process proceeds to step 347, clears the light emission prohibition flag, sets RP to "LO", and proceeds to steps 348 and S49.

In steps S48 and S49, display and other controls (for example, if this strobe has an external light control function, input and setting of a dimming F value for external light control, etc.) are performed.

When the X contact of the camera is closed, the interrupt input terminal INT of the CPU 5 becomes "LO", and the CPU 5
), the process moves to interrupt control routine step 5100.

First, in step 5101, it is checked whether or not light emission is prohibited. If light emission is prohibited, the process advances to step 5107, and the routine returns to the above-mentioned normal routine. If the light emission is not prohibited, the process proceeds to step 5102, and a delay time is added when it is sufficient for the light emission to end. This is to prevent the circuit from malfunctioning due to noise generated when the light emission is completed, that is, when the light emission is stopped, if the next operation is started during the light emission. For example, although not shown, a control circuit (such as an autofocus auxiliary light source lighting control circuit) other than the control circuit shown in FIG. If the configuration is such that no control is performed during this period, malfunctions due to noise at the start and end of light emission will not occur.

In step 5103, RP is set to "HI" and the process proceeds to step 5104. In step 5104, INT is “H”.
Check whether the X contact is open. If the X contact is open, proceed to step 5105 and check whether there is chattering at the X contact.
If there is chattering, return to step 5104 again.X
Check the contacts. If there is no chattering, step 51
Proceed to step 04, set RP="LO", and step 5107
to return to the normal routine. If X is closed in step 5104, the process advances to step 8108, and the memory RAM (2) for the number of times of light emission is checked. If the value of RAM (2) is 0, proceed to step 5ill and wait for the time set in the light emitting interval to elapse.When this time has elapsed, proceed to step 5112, set RP to LO'', start emitting light, and turn off the stem. The process returns to 5I02 and this operation is repeated.

In other words, if RAM (2) is 0, light emission is repeated indefinitely until the X contact opens.

If the value of RAM (2) is not 0 in step 8108, the process advances to step 5109, where it is checked whether the value of RAM (2) is 1 or not. If the value of RAM (2) is 1, that is, if the current light emission ends, the process advances to step 5104 and waits for the X contact to open.

Also, if the value of RAM (2) is other than 1, step 5
The process advances to step 5111, where 1 is subtracted from the value in RAM (2') (for the set number of times the light is emitted, one time of light is emitted), and the process then proceeds to step 5111, where the light is emitted repeatedly in the same manner as described above.

Additionally, if the X contact opens during the repeated light emission cycle as described above, step 5104.5105.510
The process advances to step 6.5107, and the repeated light emission is ended.

FIG. 3 shows this embodiment by its signal states. FIG. 1(A) shows the signal state during normal light emission. When the X contact is closed at ■, the output RP of the CPU 5 is "LO", so the C of the D flip-flop 3 is closed.
LK becomes "Hr" and the output Q, which is the light emission start command, becomes "H".
Then, when the xenon tube Xe starts emitting light at ■, the D flip-flop 3 is reset and the output Q becomes "LO".Furthermore, after the light emission ends, R
P becomes "Hl" and CLK is set to "T-0". When the X contact is opened at (2), the CPU 5 sets RP to "LO" at (2) after opening the X contact to prepare for the next light emission.

FIG. 3(B) shows the signal state during repeated light emission. When the X contact is closed at ■, CLK becomes "HI", the output Q of the D flip-flop becomes "HI", and ■
to start emitting light. When light emission starts, the D flip-flop is reset and Q becomes "LO". After the light emission ends, RP goes to "HI" and CLK goes to "LO" at ■. When the time set in the flash interval has elapsed (■), the CP
U5 sets the RP to "LO" again, and emits light in the same manner as in (1), (2), and (2), and repeats this for the set number of times.

From the time point ■ when the set number of times of light emission is completed, wait by setting RP to "Hl" and CLK to "LO" until the time point ■ when the X contact opens, and after opening the X contact, set RP to "L".
"O" to prepare for the next light emission.As you can see from the above, after the X contact opens, the output RP of the CPU5 becomes "L".
Even when the X contact is closed, no light is emitted, and even when the X contact is closed, light is emitted repeatedly for a set number of times.

FIG. 3(C) shows a case where a camera in which chattering occurs when the X contact is closed and opened is used.

The X contact is closed at ■, and chattering is emitted until ■. Then, a large number of clocks are input to CLK during periods (1) and (a). However, since the D input of D flip-flop 3 is always pulled up to "HI", the output Q
maintains “HI”. As a result, the xenon tube Xe starts emitting light, and after the end of emitting light, RP becomes "HI".

This causes chattering when the X contact opens. Normally, in this state, the X contact is once opened and then closed again, so this chattering causes the light to start emitting again. However, in this embodiment, since the RP terminal is at "HI" at this time, CLK remains at "LO" and no light is emitted.
○”, so even if chattering occurs at the X contact,
There is no abnormal behavior.

FIG. 3(D) shows a state in which light emission is prohibited. Even if the X contact becomes LO" in ■, RP is HI", so
"H1" is not output to LK, and light emission does not start.

In this way, since light emission can be inhibited simply by setting RP to "HI", light emission can be inhibited without using any special circuit.

〔Effect of the invention〕

As described above, according to the present invention, not only is it possible to repeatedly fire the flash multiple times with a single release operation while the strobe is attached to the camera, but also the shutter closes and the X contact opens during the repeated flash operation. When this occurs, the light emission ends at that point, and there is an advantage that unnecessary light emission is not performed.

[Brief explanation of the drawing]

FIG. 3 is a diagram showing the relationship between the amount of light emitted from the strobe and the amount of light emitted from the strobe. [Explanation of symbols of main parts] 1... Boost circuit 2...NOR circuit 3...D flip-flop 4...Comparator 5...CPU

Claims (1)

[Claims] An electronic flash device capable of emitting light multiple times while the X contact is closed, comprising: a signal for commanding a second light emission in addition to the signal from the X contact; An electronic flash device capable of repeatedly emitting light, characterized in that it emits light only when two signals simultaneously command light emission.