JP3028379U - Flash device - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To change the signal levels of a pull-up signal, a dimming signal, and a dimming confirmation signal so that these signals are transmitted and received through one common signal path, and a connecting line between a flash device and a camera To provide a flash device capable of reducing the amount of flash as much as possible. High-level pull-up signal SV ₀
Low level dimming signal SV while sending to the camera
₂ is input, and then High level dimming confirmation signal S
One shared signal path for sending V ₃ to the camera is provided, and the dimming confirmation signal level is set higher than the pull-up signal level.

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

 The present invention relates to a flash device used as an illuminator for photography, and in particular, it has a configuration in which a dimming signal sent from a camera and a dimming confirmation signal sent to the camera are output through a single shared signal path. Regarding a flash device.

[0002]

[Prior art]

 FIG. 9 shows a conventional example of a flash device. The flash device boosts the DC voltage of the power supply 11 by the DC-DC converter 12 to charge the main capacitor 13.

When the charging pressure of the main capacitor 13 reaches a predetermined value, the neon lamp 14 lights up to indicate that preparation for light emission is completed, and the ready signal circuit 15 displays a ready signal (ready for light emission). A signal indicating that) is output, and a ready signal is sent from the output terminal 16 to the camera to change the camera to the flash photographing mode.

When the light emission preparation is completed in this way, the ready signal circuit 15 outputs a pull-up signal SV ₀ of high voltage, and this pull-up signal SV ₀ passes through the resistors 21 and 22 and the output terminal 23 to the camera. Sent.

At this time, the transistor 24 holds the OFF state by the pull-up signal SV ₀ and the resistors 21 and 22. The buffer circuit 25 applies a high voltage to the gate of the IGBT 26 to turn on the IGBT 26.

When the shutter operation of the camera is performed in this state, the trigger switch 17 is closed in synchronization with the shutter operation, and the high voltage panel output from the trigger circuit 18 is added to the excitation electrode of the xenon discharge tube 19, The xenon discharge tube 19 receives the charging energy of the main capacitor 13 and emits light. The dimming confirmation signal circuit 27 is inoperative because the Low signal S1 is input from the transistor 24.

When the camera is properly exposed, the dimming signal SV _{2 of} Low voltage is input from the output terminal 23. As a result, the transistor 24 is turned on and the output of the buffer circuit 25 becomes a low voltage, so that the IGBT 26 is turned off and the xenon discharge tube 19 stops emitting light.

The dimming confirmation signal circuit 27 operates by inputting the High signal S 1 when the transistor 24 is turned on, outputs the dimming confirmation signal SV _3, and outputs the confirmation signal SV ₃ to the camera from the output terminal 20. send.

Therefore, the display portion of the camera is turned on by the confirmation signal SV ₃ , and the dimming operation can be confirmed on the camera side. Further, since the light emitting diode 28 is turned on by the operation of the dimming confirmation signal circuit 27, the dimming operation can be confirmed even in the flash device.

In addition, in such a flash device, the transistor 24 is held in the OFF state by the pull-up signal SV ₀ generated by turning on the power switch, and the IGBT 26 is turned on by the high voltage output of the buffer circuit 25. There is a configuration in which the IGBT 26 is turned on, and a configuration in which the IGBT 26 is turned on when the trigger switch 17 is turned on.

[0011]

[Problems to be solved by the device]

When the flash device described above inputs the dimming signal SV ₂ from the camera while sending the pull-up signal SV ₀ from the output end 23 to the camera, and when the dimming operation is performed. In addition, the dimming confirmation signal SV ₃ is sent from the output terminal 20 to the camera, and the signal path of the dimming signal SV _{2 and} the signal path of the dimming confirmation signal SV ₃ are separate.

However, the number of connecting lines between the flash device and the camera is reduced as much as possible, and the pull-up signal SV ₀ , the dimming signal SV ₂ , and the dimming confirmation signal SV ₃ as described above are transmitted / received through one common signal path. It is preferable to adopt a configuration. However, if the dimming confirmation signal SV ₃ is simply sent from the output end 23 to the camera as shown by the dotted line 29 in the figure, the pull-up signal SV ₀ and the dimming confirmation signal SV ₃ should be discriminated on the camera side. I can't.

That is, since the pull-up signal SV ₀ and the dimming confirmation signal SV ₃ both have the same signal level as the power supply voltage, these signals SV ₀ and SV ₃ are sent from the output terminal 23 to the camera. As shown in FIG. 10A, the signals SV ₀ and SV ₃ having the same signal level are sent to the camera, and the camera cannot discriminate these signals SV ₀ and SV ₃ . Specifically, the dimming operation cannot be confirmed on the camera side. It should be noted that FIG. 10B shows the light emission characteristic FR of the xenon discharge tube 19 when the dimming operation is performed.

In consideration of the above situation, the present invention transmits and receives the pull-up signal SV ₀ , the dimming signal SV ₂ , and the dimming confirmation signal SV ₃ through one common signal path, and connects the flash unit and the camera. It is an object of the present invention to provide a flash device of this kind, which can reduce the amount of flash as much as possible.

[0015]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, in the present invention, a switching element connected in series to a xenon discharge tube is turned on in response to a high-level pull-up signal, and a trigger voltage is applied to the xenon discharge tube to emit light. The light emitting means for controlling, the light control means for turning off the switching element in response to the low level light control signal input from the camera to stop the light emission, and the high level light control confirmation signal by the operation of the light control means. In the flash device equipped with the dimming confirmation signal generation means for sending the dimming confirmation signal to the camera, the dimming confirmation signal is input to the camera while the dimming confirmation signal is input while the pull-up signal is being sent to the camera. Providing a flash device that features one shared signal path and sets the dimming confirmation signal level higher than the pull-up signal level. To.

In the flash device according to the present invention, the dimming confirmation signal has a higher signal level than the pull-up signal. Therefore, the camera side compares these two signals to obtain the pull-up signal. Or a dimming confirmation signal.

When it is determined that the signal is a dimming confirmation signal, the display unit is operated to display, and the confirmation display of the dimming operation is performed on the camera side. As a result, according to the present invention, the flash device is configured to send and receive the pull-up signal, the dimming signal, and the dimming confirmation signal through one shared signal path.

[0018]

[Embodiment of device]

 Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram of a flash device showing a first embodiment. In this flash circuit, the same members as those in the conventional flash circuit shown in FIG. 9 are designated by the same reference numerals and the description thereof is omitted.

In the flash device of this embodiment, the ready circuit 15 includes a transistor 30, a base resistor 31 of the transistor 30, and voltage dividing resistors 32 and 33 connected to the emitter of the transistor 30. In addition, the connection P of the resistors 32 and 33 and the transistor 24 are connected.

Since the ready circuit 15 thus configured outputs the pull-up signal SV ₀ as the divided voltage of the resistors 32 and 33, the voltage of the dimming confirmation signal SV ₃ is higher than the voltage level of the pull-up signal. The level can be set high. For example, the voltage of the power source 11 may be 6V, the voltage of the pull-up signal SV ₀ may be 4V, and the voltage of the dimming confirmation signal SV ₃ may be 6V. The dimming confirmation signal output from the dimming confirmation signal circuit 27 is sent from the output end 23 to the camera.

In the ready circuit 15, when the neon lamp 14 is turned on and the transistor 30 is turned on, the ready signal output from the output terminal 16 is sent to the camera. Further, the voltage generated in the connection portion P when the transistor 30 is turned on is sent to the camera as the pull-up signal SV ₀ via the resistors 21 and 22 and the output terminal 23. Therefore, since the transistor 24 is turned off, the output of the buffer circuit 25 becomes a high voltage and the IGBT 26 is turned on.

That is, when the main capacitor 13 reaches a predetermined charging voltage, the ready signal and the pull-up signal SV ₀ shown in FIG. 2A are sent to the camera, so that the transistor 24 is turned off and the IGBT 26 is turned on. Turn on. When the trigger switch 17 is closed in synchronization with the camera shutter, an excitation voltage is applied to the xenon discharge tube 19 and the xenon discharge tube 19 emits light.

When the camera is properly exposed and the dimming signal SV ₂ is input from the output terminal 23, the transistor 24 is turned on by the dimming signal SV ₂ which is a Low voltage, and the buffer circuit 25 is set to the gate of the IGBT 26. Input the signal. Therefore, similarly to the conventional example, the IGBT 26 is turned off to stop the emission of light from the xenon discharge tube 19, and the dimming confirmation signal SV ₃ output from the dimming confirmation signal circuit 27 is sent to the camera via the output end 23. .

FIG. 2A shows the pull-up signal SV ₀ , the dimming signal SV ₂ , and the dimming confirmation signal SV ₃ which are transmitted and received to and from the camera by the output terminal 23. Since the confirmation signal SV ₃ is set to a higher voltage level than the pull-up signal SV ₀ , the camera side can reliably discriminate the dimming confirmation signal SV ₃ from the pull-up signal SV ₀ . The camera may be provided with a comparator for comparing the pull-up signal SV ₀ and the dimming confirmation signal SV ₃ so that the signals SV ₀ and SV ₃ can be discriminated from each other. Note that FIG. 2B shows the light emission characteristic FR of the xenon discharge tube 19 when the light control operation is performed as described above.

Further, FIG. 3A shows the pull-up voltage SV ₀ when the flash device described above emits full light, and FIG. 3B shows the emission characteristic F R of the xenon discharge tube 19 which emits full light. There is.

FIG. 4 is a circuit diagram of the flash device according to the second embodiment. This flash device is different from the flash circuit of the first embodiment shown in FIG. 1 in that a pull-up signal SV ₀ (first voltage) is provided between the gate voltage circuit 35, the connection portion P of the ready circuit 15 and the output terminal 23. And a diode 36 for outputting a pull-up signal). The gate voltage circuit 35 outputs a gate signal SV ₁ (second pull-up signal) in response to the input of the operation signal S2 of the trigger circuit 18, and the gate signal SV ₁ is resistance-converted. It is designed to be sent to the camera via 21, 22 and the output terminal 23.

In the flash device configured as described above, the transistor 30 of the ready circuit 15 is turned on to output the ready signal, and at the same time, the voltage generated in the connection portion P is output from the output end 23 to the camera as the pull-up signal SV _0. Sent.

When the trigger switch 17 is closed in synchronization with the camera shutter, a trigger voltage is applied to the excitation electrode of the xenon discharge tube 19 and a trigger operation signal S 2 is input to the gate voltage circuit 35. To do. As a result, the gate signal SV ₁ output by the gate voltage circuit 35 is sent to the camera through the resistors 21, 22 and the output terminal 23.

When the gate signal SV ₁ described above is output, the transistor 24 is turned off, the IGBT 26 is turned on, the xenon discharge tube 19 emits light, and when the camera reaches the proper exposure, the camera is exposed. The low-level dimming signal SV ₂ sent is input from the output terminal 23, the transistor 24 is turned on, the IGBT 26 is turned off and the light emission is stopped, and then the dimming confirmation signal circuit 27 outputs the dimming confirmation. The signal SV ₃ is sent to the camera via the output end 23.

FIG. 5A shows the pull-up signal SV ₀ , the gate signal SV ₁ , the dimming signal SV ₂ , and the dimming confirmation signal SV ₃ transmitted and received at the output terminal 23 as described above. (B) shows the emission characteristic FR of the xenon discharge tube 19 when the light control operation is performed as described above. 6 gate and Puruatsupu signal SV ₀ when the flash device of the second embodiment has a full emission - DOO signals SV ₁ and indicates, FIG. 6 (B) light emission of the xenon discharge electric tube 19 when the full light emission The characteristic FR is shown.

In the flash device according to this embodiment, the signal level of the dimming confirmation signal SV ₃ is set higher than that of the pull-up signal SV ₀ , and the comparators provided with these SV ₀ and SV ₃ on the camera side. Can be identified by. Also, gate - DOO the signal SV ₁ DOO dimming confirmation signal SV ₃ is as same level of the signal, gate - DOO signal SV ₁ generation time t ₁ to 5 ms, dimming confirmation signal SV ₃ time of occurrence t _{Since 2} is set to about 2 seconds, the display unit on the camera side does not turn on by the gate signal SV ₁ , but turns on by the dimming confirmation signal SV ₃ .

Although the embodiment of the present invention has been described above, the level of the pull-up signal SV _{0 and} the level of the dimming confirmation signal SV ₃ can be appropriately determined as necessary. For example, as shown in FIG. 7, the resistor 37 and the Zener-diode - connected in series circuit of de 38 a in parallel with the main capacitor 13, the Zener-diode - Output a constant voltage of de 38 as the dimming confirmation signal SV ₃ By doing so, it is possible to set the power supply voltage 6V, the voltage 6V of the pull-up signal SV ₀ , and the voltage 8-10V of the dimming confirmation signal SV ₃ .

Note that FIG. 8A shows the pull-up signal S V ₀ , the dimming signal SV ₂ , and the dimming confirmation signal SV ₃ when these signals are set in this way, and FIG. 8B shows The emission characteristic FR of the xenon discharge tube 19 when the light control operation is performed is shown. Besides, the power supply voltage 12V, the voltage 6V of the pull-up signals SV _0, it can be determined in the voltage 8~10V dimming confirmation signal SV _3.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram of a flash device according to a first embodiment of the present invention.

FIG. 2A shows a pull-up signal, a dimming signal, and a dimming confirmation signal when the flash device performs a dimming operation. FIG. 2B shows a light emission characteristic when the flash device performs a dimming operation.

FIG. 3A shows a pull-up signal when the flash device emits full light. FIG. 3B shows a light emission characteristic when the flash device emits full light.

FIG. 4 is an electric circuit diagram of a flash device according to a second embodiment of the present invention.

FIG. 5A is a pull-up signal, a gate signal when the flash device of the second embodiment performs a dimming operation,
A dimming signal and a dimming confirmation signal are shown. FIG. 5B shows a light emission characteristic when the flash device of the second embodiment performs a dimming operation.

FIG. 6A shows a pull-up signal and a gate signal when the flash device of the second embodiment emits full light. FIG. 6B shows light emission characteristics when the flash device of the second embodiment emits full light.

FIG. 7 is a partial circuit diagram of a flash device showing a modified example.

FIG. 8A shows a pull-up signal, a dimming signal, and a dimming confirmation signal of the above modification, and FIG. 8B shows a light emission characteristic.

FIG. 9 is an electric circuit diagram of a flash device shown as a conventional example.

FIG. 10A is an explanatory diagram for explaining a problem of the conventional flash device. FIG. 10B shows a light emission characteristic when the conventional flash device performs a dimming operation.

[Explanation of symbols]

 12 DC-DC converter 13 Main capacitor 14 Neon lamp 15 Ready signal circuit 18 Trigger circuit 23 Output terminal 24 Transistor 25 Buffer circuit 26 IGBT 27 Dimming confirmation signal circuit

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[Procedure amendment]

[Submission date] March 25, 1996

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Scope of utility model registration request

[Correction method] Change

[Correction content]

[Scope of utility model registration request]

Claims (1)

[Scope of utility model registration request] 1. A switching element connected in series with a xenon discharge tube is turned on in response to a high level pull-up signal.
Means for setting the N state, light emitting means for applying a trigger voltage to the xenon discharge tube to emit light, and Lo input from the camera
Light control means for turning off the switching element in response to a w level light control signal to stop light emission, and a light control signal generation for sending a high level light control confirmation signal to the camera by the operation of the light control means In the flash device including means, a dimming signal is input while the pull-up signal is being sent to the camera, and then a shared signal path for sending a dimming confirmation signal to the camera is provided, and dimming confirmation is performed. A flash device characterized in that the signal level is set higher than the pull-up signal level.