JP2907287B2 - Flash light emitting device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flash light emitting device, and more particularly to a flash light emitting device having a function of preventing a red-eye phenomenon.

[Prior Art] When performing flash-synchronous shooting with a person or an animal as a subject and firing a strobe, if the distance between the optical axis of the taking lens and the center of the flash discharge tube of the strobe is short, the subject's eyes turn red. It is well known that a red-eye phenomenon occurs.

Therefore, various means for preventing the occurrence of the red-eye effect have been conventionally provided. As a typical means, as disclosed in Japanese Patent Publication No. 58-48088, immediately before performing flash synchronous photography, a flash lamp other than the flash discharge tube of the strobe is turned on for a certain period of time, and After closing the pupil of the eye, a flash discharge tube to be tuned to emit light, as disclosed in JP-A-58-20021,
Next formula In order to satisfy the following, there is known an image pickup apparatus in which a distance between an optical axis of a photographing lens and a flash discharge tube of a strobe is increased.

[Problems to be Solved by the Invention] The cause of the occurrence of the red-eye phenomenon is that the pupil of the eye is open in darkness or the like. Yes,
Accordingly, in the red-eye prevention means described in Japanese Patent Publication No. 58-48088, a lamp is turned on for a certain period of time immediately before flash-synchronized shooting, thereby closing the pupil. However, in this prevention means, a lamp is provided separately from the flash discharge tube, and since this lamp is turned on, the device becomes large, and it is necessary to turn on the lamp for a long time of 1.3 seconds. There is a disadvantage that the time until the start of shooting is long.

In addition, the red-eye prevention means described in Japanese Patent Application Laid-Open No. 58-20021 requires that the distance between the optical axis of the taking lens and the discharge tube of the strobe be further increased as the GNo (guide number) increases. However, if the focal length of the lens becomes longer, the distance between the optical axis of the lens and the strobe discharge tube must be further increased.

By the way, when the pupil of the eye is closed, generally, "light reflex of the pupil (reflection in which the pupil contracts when light enters the eye or suddenly becomes brighter) is latency (response delay time)
It takes 0.2-0.5 seconds until the response ends, that is,
It takes approximately one second or more to reduce the pupil diameter according to the light. Moreover, to reduce the pupil to the minimum diameter, 1000ftcd
The above brightness is required, and the efficiency is very poor with constant light. This is because the pupil first tries to contract rapidly at the moment of the light, but if the light is continuous light, the light gradually decreases to a size corresponding to the brightness thereafter. This is because the reflection against light is caused not by the absolute value of light but by the change of light.

Therefore, as in the method for preventing red-eye described in Japanese Patent Publication No. 58-48088, the method of performing flash tuning photography by closing the pupil by turning on the lamp continuously before flash emission of the strobe is inefficient, In addition, the effect differs depending on the ambient light. On the other hand, a method of performing flash emission with high luminance once before flash photography, closing the pupil, and then performing flash tuning photography is also conceivable. This method is not affected by ambient light because the brightness of the flash is high, but it requires a light emission of GNo10 or more to perform effective preliminary light emission, and until the pupil reaches the maximum response However, since it takes more than one second, the efficiency is not very good.

A first object of the present invention is to reduce the size and release of a flash by performing a pre-flash (preliminary flash) including a plurality of flashes for reducing the pupil in order to prevent the red-eye phenomenon before the flash for photographing. An object of the present invention is to provide a flash light emitting device that can prevent red-eye with a small time lag.

A second object of the present invention is to provide a flash light emitting device capable of switching between the light emission mode for preventing the occurrence of red-eye and the normal flash light emission mode.

[Means and Actions for Solving the Problems] The flash light emitting device according to the present invention responds to a release signal from a camera as shown in FIG.
Until opening operation immediately before the start of the shutter, to perform the pre-light emission P _A composed of high luminance multiple flash light emission for the pupil constriction, causing a tuning flashlight P _C as a taken after opening operation start of the shutter It is characterized by doing so.

When the pre-emission P _A is performed, the reaction end time of the pupil is reduced from 1.3 to 1.6 seconds to 0.5 to 0.9 seconds as compared with the conventional method in which the constant light is pre-emission P _B shown in FIG. Can be expedited.

In other words, when the results of experiments performed on several persons are graphed, as shown in FIG. 2, the response of reducing the diameter of the pupil ends when the interval of flash light emission composed of high-intensity minute pulse light is set to 50 ms. It takes about 0.7 seconds.
Also, the energy used for pre-emission can be greatly reduced.

EXAMPLES Hereinafter, the present invention will be described with reference to the illustrated examples.

3 to 5 show a first embodiment of the present invention. The configuration of the flash light emitting device of the first embodiment is
As shown in the figure, it is composed of a flash light emission circuit and a light emission drive circuit. The flash light emitting circuit includes a boost power supply circuit 1 composed of a DC-DC converter and a main capacitor connected to an output terminal of the power supply circuit 1 via a rectifying diode 3.
C ₁ and the flash discharge tube Xe, the emission control circuit 4, the discharge tube X
e, and the light emission drive circuit is formed by a release switch that is closed by a release operation.
SW ₁ , a first one-shot multi-circuit 5 to which a signal is input from the switch SW _1, a first counter 6 and a pulse generation circuit 7 to which outputs of the circuit 5 are respectively input, Second counter 8 to which the output is input
And a second one-shot multi-circuit 9 to which the output of the counter 8 is input, and a drive signal to be applied to the trigger circuit 2 and the light emission control circuit 4 by receiving the output of the multi-circuit 9 and the output of the pulse generation circuit 7. It comprises an OR circuit OR ₁ and an oscillator 10 for driving the first counter 6 and the second counter 8.

The boosting power supply circuit 1, trigger circuit 2 and light emission control circuit 4 are configured as shown in FIG. 5 as specific electric circuits. That is, the booster power supply circuit 1 is connected across the power supply battery E ₀ through the power switch SW _0,
Transistor T _r1, resistor R _1, a series circuit of resistors R _2, 1 winding of the step-up transformer T _1, the series circuit and the capacitor C ₂ of the transistor T _r2, a series circuit of resistors R _3, of the step-up transformer T ₁ The secondary winding and the secondary winding are connected as shown in the figure.

In this way it configured boosting power supply circuit 1, when closing the power switch SW _0, through a resistor R ₃ base current flows through the transistor T _r1, flow collector current in the transistor T _r1. This collector current is _{equal to the} transistor _Tr2
And a collector current flows through the transistor _Tr2 . Then current flows through the primary winding of the step-up transformer T _1, 1 to the secondary winding by flux linkage with respect to the secondary winding of the winding high voltage is induced, the rectifying diode 3 from which the output end It will flow a charging current to the main capacitor C ₁ through. This charging current is determined by the transistor T
to flow through the _r1 based further transistor T _r1
, The collector current flows, and therefore, the base current of the transistor _Tr2 increases, and accordingly, the collector current increases,
The connection with an increased charging current to the main capacitor C _1, the transistor T _r2 This positive feedback effect becomes saturated. Then, since there is no change in current on the primary side, there is no change in magnetic flux on the secondary side. Thus the energy in a direction reverse biasing the diode 3 is generated in the secondary side, a transistor T _r2 also off by turning off by reverse bias the transistor T _r1 (1 cycle end).
Here, vibration occurs in the secondary winding, and the transistor T
When half-wave positive bias to _r1, turned on the transistor T _r1 again starts to return the next cycle of operation to the initial state. In this way, performing the charging of the main capacitor C ₁ by performing oscillation operation.

Further, the trigger circuit 2 includes a resistor R ₄ , a thyristor SCR ₁
, A trigger capacitor C ₃ and a trigger transformer T ₂ , and resistors R ₅ and R ₆ .The trigger capacitor C ₃ is charged in advance with the charging of the main capacitor C _1. I have. Then, the SCR ₁ and the signal is inputted through a resistor R ₆ to the gate of the SCR ₁ is turned on, the charge of the trigger capacitor C ₃ is supplied to the primary winding of the trigger transformer T ₂ through SCR _1. Then, high voltage is generated in the secondary winding of the trigger transformer T _2, which is applied to the trigger electrode, to trigger the flash discharge tube Xe.

The light emission control circuit 4 includes an insulated gate bipolar transistor (IGBT) connected in series to the flash discharge tube Xe.
the transistor T _r3 called ransistor), diode
A series circuit of D ₁ , resistors R ₇ and R ₈ , a constant voltage diode ZD,
Transistor T _r4 through T _r6 and the resistor R ₉ to R _13, capacitors C
₄ and is connected as shown, be configured, the resistor R _7, a constant voltage diode ZD, a capacitor C ₄ forms a driving power source of the transistor T _r3.

Incidentally, the OR circuit OR ₁ is in fact form a NOT ₁ circuit with an inverter I _1, through which is adapted to apply a signal to the base of the transistor T _r6,
Moreover, further adapted to apply a signal through an inverter I ₂ in the trigger circuit 2.

The output of the above NOT ₁ circuit is "H" in the _normal state, the transistor _Tr6 is on, the transistor _Tr4 is off, the transistor _Tr5 is on standby, and the gate of the transistor _Tr3 is 0V. _Therefore , the transistor _Tr3 does not turn on. When the output of the second one-shot multi-circuit 9 or the pulse generation circuit 7 turns off the transistor _Tr6 through the NOT ₁ circuit, the transistor _Tr4 turns on, and a voltage is applied to the gate of the transistor _{Tr3. Tr3} turns on. However, the gate of the transistor _Tr3 is biased by the pulse width of the second multi-circuit 9 or the pulse generation circuit 7. That is, the flash discharge tube Xe emits light by the pulse width. In addition,
By connecting a capacitor in parallel with the resistor R _11, or faster rise of the gate bias of the transistors T _r3, may be reverse biased gate of the transistor T _r3 during on of the transistor T _r5.

Next, the operation of the flash light emitting device of the first embodiment having such a configuration will be described with reference to the time chart of FIG. A release by the switch SW ₁ is closed release signal is input, the signal is input to the first one-shot multivibrator circuit 5, the pulse output of the circuit 5 is set terminal S of the first counter 6 and the pulse generator 7 And drive each. The first counter 6 is a time constant circuit for counting from release until the shutter start, the pulse generating circuit 7 is formed by the pulse circuit for sending a pulse to the OR circuit OR ₁ at predetermined intervals. As described above, the pulse generation circuit 7 operates in synchronization with the release, and when the pulse is input to the light emission control circuit 4 through the OR circuit OR ₁ and the inverter I ₁ and further to the trigger circuit 2 through the inverter I ₂ , both circuits 2 , 4 are driven, so that multiple pre-emissions with high luminance are performed at predetermined intervals. Thus, this reduces the pupil and prevents the red-eye effect from occurring.

On the other hand, the output of the first counter 6 is input to the second counter 8 and the reset terminal R of the pulse generation circuit 7, respectively. Then, the shutter starts to operate at the same time as the second counter 8 is started, and the pulse generation circuit 7 is reset, so that the pulse output is stopped. The second counter 8
Is a timing circuit that counts the time corresponding to the time from the shutter opening operation to the full opening. After the time measurement is completed, an output is generated and the output is input to the second one-shot multi circuit 9. A flash emission signal is supplied from the one-shot multi-circuit 9 to the OR circuit OR ₁
To the light emission control circuit 4 through the inverter I ₂
Is input to the trigger circuit 2 through the flash memory, so that flash light emission synchronized with the original shutter of the flash is performed to perform flash photography.

In this connection, pre-emission P _A in this embodiment, as shown in the time chart of FIG. 4, GNo (guide number) = 1
With a considerable amount of light, the light emission interval was 50 ms, the number of times of light emission was 14 and the time lag from shutter release to shutter release was 0.9 seconds.

In the above first embodiment it has been described as a flash built in the camera, which uses a strobe is separate from the camera body, to replace the release switch SW ₁ to the release signal, receives a release synchronization signal from the camera body , First
In addition to the input to the one-shot multi-circuit 5, the shutter opening operation is started by the output of the first counter 6 instead of measuring the time from the shutter opening operation to the shutter fully opening by the second counter 8. Of course, a normal X-contact ON signal may be input to the second one-shot multi-circuit 9. This is the same in the second and third embodiments described below.

Next, a second embodiment of the present invention will be described with reference to FIGS.

The flash light emitting device according to the second embodiment is different from the flash light emitting device according to the first embodiment in that a pre-light emission for preventing red-eye and a normal flash light emission are previously provided as shown in the circuit of FIG. in that the mode switch SW ₂ for selecting appended me. Therefore, the photographer can use this mode switch SW ₂
When the terminal R ₀ is switched to the alligator, a red-eye mode is performed in which the flash is performed after the pre-emission for preventing red-eye, and when the terminal N ₀ is switched to the other side, only the flash is performed without the pre-emission. Flash mode can be selected.

In other words, if you select the red-eye mode switches the mode switch SW ₂ to the terminal R ₀ is a second AND circuit the AND ₂ is opened, since the first AND circuit the AND ₁ is closed, the first embodiment The configuration is exactly the same as that of the electric circuit (see FIG. 5), and the operation sequence is the time chart shown in FIG. 7. After the pre-flash operation, the flash photography synchronized with the shutter is performed.

Further, when switching the mode switch SW ₂ to the terminal N ₀ selects the normal flash emission mode, a second AND circuit the AND ₂ is first AND circuit the AND ₁ is closed is opened. The operation sequence at this time is as shown in the time chart of FIG. That is, when you turn on the release switch SW _1, the first
Pulse is generated from the one-shot multivibrator circuit 5, the pulse passes through the first AND circuit the AND _1, starts the second counter 8 via the second OR circuit OR _2. The second counter 8 outputs an output when a predetermined time is counted, and the second one-shot multi-circuit 9 generates a flash emission pulse signal. Then, the light emission control circuit 4 and the trigger circuit 2 are driven by these, and flash light emission is performed, and flash photography is performed.

FIGS. 9, 10, and 11 show a third embodiment of the present invention. The flash light emitting device of the third embodiment is the same as that of the second embodiment.
In flash light emission device of example, what has been selected and the red-eye mode and the normal mode by the mode switch SW _2, as illustrated in FIG. 9, the object distance information, focal length information of the lens, field brightness Information, information on the distance between the strobe and the photographing lens, and the like are input to a determination circuit 11, where it is determined whether or not red-eye occurs, and the mode is automatically switched to a red-eye mode or a normal mode. That is, when the determination circuit 11 calculates and determines that red-eye occurs, the terminal R
_{At 0} , a pulse signal for preventing red-eye is generated, and the pulse signal is input to the first counter 6 and the pulse generation circuit 7 to generate a 10th pulse signal.
After pre-emission by operating as shown in the time chart in the figure, the flash is emitted by operating the shutter.

Further, when the determination circuit 11 red-eye effect does not occur is determined generates a pulse signal to the terminal N _0, to perform the sequence operation to the time chart shown in FIG. 11, the shutter operation without pre-emission Flash synchronization photography is performed.

When the following conditional expression is satisfied, the determination circuit 11 determines that a red-eye phenomenon occurs and outputs a pulse signal for preventing red-eye to the terminal _R0 . (A) The distance d, which is the distance between the optical axis of the photographing lens and the center of the flashlight discharge tube Xe of the strobe, and the subject distance l are: (B) The subject distance l, the focal length f, and the interval distance d are In this case, it is determined that red-eye occurs.

Next, FIG. 12, FIG. 13, FIG. 14 and FIG.
It shows an example. In the fourth embodiment, the flash light emitting device of the present invention is incorporated in a fully automatic camera, that is, a camera which automatically performs photometry, ranging, exposure, film winding, and the like. As shown in the figure, a sequence controller for performing a camera operation is constituted by a CPU 12, and the photometry and distance measurement operations are operated by a photometry and distance measurement drive circuit 13 controlled by the CPU 12.
Further, the photographing lens is a lens driving motor M _1, the shutter is a shutter driving motor M _2, the film motor Volume 1
Automatically brought operate respectively M _3, the motor M ₁ ~M ₃ is adapted to be controlled by a motor control circuit 14. Further, the CPU 12 issues a photometry and distance measurement command by the first release in which the release switch SW _1a is pressed down one step,
Red-eye determination is performed at the time of the second release when the shutter is pressed down two steps, and a pre-emission signal or a flash emission signal is output to the flash emission circuit.

The flash light emitting circuit includes a booster power supply circuit 1A consisting of a DC-DC converter, the power supply circuit 1A main capacitor C ₁ and the and the flash discharge tube Xe connected through a rectifier diode 3 to the output terminal of the light emission control circuit 4A and the trigger circuit 2 of the discharge tube Xe.

The booster power supply circuit 1A is connected to both ends of the power supply battery E ₀ through the power switch SW _0, transistor T _r11, the resistance R
_21, a series circuit of R _22, transistor T _r12, T _r13, the resistance R _23, R
A series circuit of _24, the primary winding of the step-up transformer T _1, the series circuit of the transistor T _r14, 2 winding of the transformer T _1, resistors R
A series circuit of _25, and a capacitor C ₂ and the resistor R _26, R ₂₇ are constituted are wired as shown. Since the boost power supply circuit 1A is a well-known circuit, the description of its operation is omitted, but the signal of the signal from the CPU 12 to the transistor _Tr11 is transmitted.
The DC and DC converter can be controlled by H and L.

Since the trigger circuit 2 is exactly the same as that of the first to third embodiments, its description is omitted.

The light emitting control circuit 4A is connected to the output terminal of the power supply circuit 1A, the resistor R _28, a series circuit of a capacitor C _5, a coil L ₁ is connected to both ends of the capacitor C _5, a series circuit of the thyristor SCR ₂ , And resistors R ₂₉ and R ₃₀ .

The operation of the flash light emitting circuit thus configured will be described with reference to the time chart of FIG. Power switch SW ₀ is closed, the drive signal is made to the booster power supply circuit 1A from CPU 12, the circuit 1A operates, which charges the main capacitor C _1, resistors trigger capacitor C ₃ and the capacitor C ₅ R through ₄ and resistors R ₂₈ each charge so that the potential across the substantially the same potential of the main capacitor C ₁ in.

Here, the trigger signal to the SCR ₂ is a discharge of the capacitor C ₅ is applied from the CPU 12, the charge of the capacitor C ₅ is discharged through the coil L _1, SCR _2, capacitor C _5, a coil L ₁ the resonance of the reverse charge is made to the capacitor C _5, the potential of the capacitor C ₅ and the flash discharge tube Xe,
When the voltage of the main capacitor C ₁ and V _CM, a substantially -V _CM. At this point, SCR ₂ is turned off. Therefore, a voltage of 2 V _CM is applied to the discharge tube Xe, and the discharge tube Xe is discharged.
Xe easily emits light (the same effect as the conventional pull-down circuit is obtained). At this point, SCR ₁ to emit light and discharge tube Xe trigger signal applied from CPU 12, the light emitting to be charged in the capacitor C ₅ is stopped.

With this operation as one cycle, pre-emission is performed a plurality of times. During flash light, first it sends a signal to the SCR _2, SCR ₂
Was turned on, the voltage of the capacitor C ₅ as -V _CM, then emit light discharge tube Xe sends a signal to the SCR _1. Then the voltage of the capacitor C ₅ is increased. But still SCR ₂
When the anode voltage of the SCR ₂ , that is, the voltage of the capacitor C ₅ exceeds the ON voltage of the SCR ₂ , the discharge current of the discharge tube Xe is discharged through the SCR ₂ . Therefore, flash light emission is performed.

Next, the operation of the fully automatic camera having the flash light emitting device will be described with reference to FIGS. 12 to 15. As shown in the flowchart of FIG. 13 and the time chart of FIG.
Photometry and ranging are performed at the time of release, and the data is stored in the CPU 12 by the memory. Here, when the first release is performed again, the stored data is refreshed to a new value. After that, when the 2nd release is pressed, the pre-emission pulse is
Send from 12 to SCR ₂ , then trigger capacitor to SCR ₁
It sends the discharging pulse of the C _3. This pulse is continued for a predetermined time, and then a shutter operation signal is sent from the CPU 12 to the motor control circuit 14, and when the shutter is released, the CPU 12
It sends a pulse synchronized with the CR ₁ and SCR _2, to perform flash light emission. Thereafter, the shutter closes, winds up, and returns to the initial state.

In the above-described embodiment, the flash light for photographing is emitted when the shutter is fully opened. However, in a camera employing a type of shutter that synchronizes at full speed, such as a lens shutter type camera, if the shutter is opened. Needless to say, it is only necessary to make a flash light emission even if it is not fully opened.

FIG. 16 and FIG. 17 show a fifth embodiment of the present invention. The flash light emitting device of this embodiment is configured separately from a camera, and is connected to a camera body (not shown) by a synchro contact terminal X ₀ , a clock terminal CK, and a data bus terminal D.
B and the ground terminal G.

In the flash light emitting circuit of this embodiment, the boosting power supply circuit 1A and the trigger circuit 2 are the same as the circuit of the fourth embodiment (see FIG. 12).
The light emission control circuit 4B includes a series circuit of the SCR ₃ and the resistors R ₃₁ and SCR ₄ connected in series to the flash discharge tube Xe, and the capacitors C ₆ and C ₇ and the resistor R ₃₂ , R ₃₃ , R ₃₄ , R
₃₅ and R ₃₆ are connected as shown. Also, a CP that controls the sequence of the flash light emitting circuit
U15, the A / D converter to the resistor R _37, look like divided voltage of the main capacitor C ₁ which is divided by the R ₃₈ is input, this voltage reaches a pre Ji order set value ,
The charging voltage is controlled by turning off the transistor _Tr11 of the boost power supply circuit 1A.

In operation of the flash light emission device of the fifth embodiment is configured such with the time chart of FIG. 17, so that the transistor T _r11 to close the power switch SW ₀ ON state, the transistor T _r12 Is turned on and DC-D
The C converter starts oscillating, and the main capacitor C ₁ , the trigger capacitor C ₃ , the capacitor
Charge C ₆ and C ₇ .

In this state, first, when the red-eye mode is selected, a pre-emission start signal is input to the clock terminal CK and the data bus terminal DB. Then, a pulse signal train as shown in FIG. 17 is generated at the output terminals T ₀₁ and T ₀₂ . First, when the pulse signal to the terminal T ₀₁ is generated SCR ₁ is turned on, a trigger voltage is applied to the flash discharge tube Xe. Therefore, a current flows through the flash discharge tube Xe → the capacitor C ₆ → the capacitor C ₇ → the gate of the SCR ₃ and the discharge tube Xe starts discharging. Then the pulse to the terminal T ₀₂ is generated, the SCR ₃ reverse bias capacitor discharged C ₆ which has been accumulated through pre Ji because resistor R _31, R ₃₄ turns on the SCR _4, the SCR ₃ as an off Stops emitting light.

This operation is repeated by the pulses sequentially generated at the terminals T ₀₁ → T ₀₂ and T ₀₁ → T ₀₂ , so that the pre-emission is performed a plurality of times and the red-eye is prevented. The pulse generation interval is set in advance, and the time from T _{01 to} T ₀₂ is also determined in advance.

When the pre-emission is performed, a shutter operation signal is input to the terminal DB. Then, the pre-emission stops. The shutter operation signal applied to the terminal DB is applied from the start of the shutter operation to the time when the shutter is closed. Further, the CPU 15 is provided with a timer that starts counting from the start of the pre-emission, and the pre-emission stops when the timer ends. However, if a shutter operation signal is generated at the terminal DB before the end of the time measurement, this is determined as an abnormal state of the circuit system, and the pre-emission is stopped.

Thereafter, when the signal on terminal X ₀ is input to generate an output to the terminal T _01, and starts the emission of the discharge tube Xe. When the amount of emitted light becomes appropriate, a signal is input to the clock terminal CK, a signal is output to the output terminal _T02 , and light emission is stopped. Incidentally, the data bus terminal DB is and "L", the only, so as to enter the same signal is when the input sync emission signal to the PC terminal X _0.

Next, when the normal light emission mode is selected, the terminals CK and DB
, A normal mode signal is generated. Then, no signal is generated at the output terminals T ₀₁ and T ₀₂ until a signal is input to the terminal X ₀ . Output terminal and synchro emission signal to the terminal X ₀ is input
Signal is generated to T _01, the discharge tube Xe starts emission. Then, when the proper light amount is reached, a signal is input to the terminal CK, a signal is generated at the output terminal _T02 , and light emission is stopped.

[Effects of the Invention] As described above, according to the present invention, the following remarkable effects can be obtained. That is, in the present invention, the optic nerve of the eye utilizes the basic principle that, by its nature, the continuity of pulsed light can feed back a larger response to the pupil than the constant light, and before the flash-synchronized flash photography, Since the high-intensity continuous pulse light is generated a predetermined number of times by the flash discharge tube, (1) flash light is emitted after the pupil is closed, and the red-eye phenomenon at the time of flash-synchronized shooting can be prevented.

(2) Since the pupil contraction reaction is fast, the duration of the pulse light before flash emission is shortened, thereby releasing the shutter.
The time lag from pre-flash to flash synchronization shooting can be shortened, so that a shutter chance is not missed.

(3) Since the pulse light for pupil reduction is emitted by the same flash discharge tube that emits flash light, the apparatus can be downsized.

(4) The continuous pulse light for pupil reduction has a small amount of light but a high luminance, so that the pupil is reliably reduced without being affected by ambient light.

[Brief description of the drawings]

1 (A) and 1 (B) are diagrams showing light emission for pupil reduction for explaining the principle of the present invention, and FIG. 2 is a graph showing the relationship between the light emission interval of pulse light and the pupil reaction time. FIG. 3 is an electric circuit diagram of a flash light emitting device showing a first embodiment of the present invention, FIG. 4 is a time chart of an electric circuit of the device of the first embodiment, FIG. FIG. 6 is a specific electric circuit diagram of the flash light emitting circuit of the flash light emitting device according to the first embodiment, FIG. 6 is an electric circuit diagram of the flash light emitting device according to the second embodiment of the present invention, and FIGS. FIG. 9 is a time chart showing the operation of the electric circuit of the device of the second embodiment, FIG. 9 is an electric circuit diagram of a flash light emitting device showing a third embodiment of the present invention, and FIGS. FIG. 12 is a time chart showing the operation of the electric circuit of the device according to the embodiment, and FIG. 12 is an electric circuit diagram of the flash light emitting device according to the fourth embodiment of the present invention. Road map, FIG. 13 is a flowchart showing the operation of the device of the fourth embodiment, FIGS. 14 and 15 are time charts showing the operation of the electric circuit of the device of the fourth embodiment, respectively, and FIG. FIG. 17 is an electric circuit diagram of a flash light emitting device showing a fifth embodiment of the present invention. FIG. 17 is a time chart showing the operation of the electric circuit of the device of the fifth embodiment. P _A ... Flash light emission for pupil contraction P _C ... Flash light emission for shooting SW ₁ ... Release switch (release signal) SW ₂ ... Mode switch 11 ... Judgment circuit (switching circuit) 12 ... CPU (〃)

Claims (4)

(57) [Claims] 1. A repetitive emission signal output for responding to a release signal instructing the start of a shutter opening operation of a camera and repeatedly outputting a light emission start signal a predetermined number of times until the shutter opening operation is started. Means, output number setting means for determining the number of times the light emission start signal is output, shooting light emission signal output means for outputting a light emission signal for shooting after the shutter opening operation is started, and light emission start output from the repeated light emission signal output means A light emitting unit that emits light for pupil contraction in response to a signal and emits light for photographing in response to a light emission signal for photographing output from the light emission signal output unit for photographing. 2. A pre-emission signal output, which is generated in response to a release signal instructing the start of a shutter opening operation of a camera and which is repeated a predetermined number of times of a pre-emission signal until the start of the shutter opening operation. Means for setting the number of outputs of the pre-emission signal; output number setting means for determining the number of outputs of the pre-emission signal; imaging emission signal output means for generating an imaging emission signal after a shutter opening operation is started; and pupil constriction emitting light in response to the pre-emission signal A flash comprising: a light emitting unit; a photographing light emitting unit that emits light in response to the photographing light emission signal; and a switching unit that outputs an output for selecting operation or non-operation of the pre-light emission signal generating unit. Light emitting device. 3. The switching means outputs an output according to a red-eye occurrence factor such as a distance between a photographing lens and a discharge tube, a distance to a subject, a focal length of the photographing lens, and subject brightness. 2. The flash light emitting device according to 2. 4. A first pulse generating means for generating a pulse signal at a predetermined interval between the start of the release operation of the camera and immediately before the start of the shutter opening operation, and a second pulse for generating a pulse after the start of the shutter opening operation. A flash light emitting device that repeats pre-emission according to a pulse from the first pulse generation means and performs main light emission according to a pulse from the second pulse generation means. Shooting equipment.