JP2003274240A - Portable telephone with camera and power supply circuit for stroboscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a portable telephone with camera incorporating a small volume lightweight stroboscope in which limitation on the number of light emitting times can be eliminated. <P>SOLUTION: A power supply (a lithium ion cell) 31 for other units in a portable telephone is employed as the power supply for a stroboscope. The power supply circuit 30 of the stroboscope comprises a constant voltage circuit 33 for converting the voltage of the power supply 31 into a specified voltage, and a semiconductor switch (FET switch circuit) 34 for controlling output from the constant voltage circuit 33 to the circuit 10 on the stroboscope side. The circuit 10 on the stroboscope side requires no dry battery. The FET switch circuit 34 is turned ON so long as the stroboscope is set, and a voltage is delivered from the constant voltage circuit 33 to the circuit 10. When a strobo light emitting switch 35 is turned ON upon completion of charging through a charging element 14, a xenon discharge lamp 22 emits light. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera-equipped mobile phone and a power supply circuit for a flash device thereof.

[0002]

2. Description of the Related Art So-called mobile phones, which are portable phones,
In recent years, mobile phones such as PHS have been improved so as to have various functions, and those having a function of taking a photograph such as a small digital camera in addition to a call and communication function are becoming popular. This shooting function is used for all pixel readout CCD and C
-It is realized by using a MOS image sensor.

A CCD is a semiconductor device characterized by photoelectrically converting optical information into an electric signal. Light entering from a lens is collected by the CCD and detected by a CCD area sensor. The CCD area sensor is a surface sensor in which pixels are arranged vertically and horizontally, which corresponds to a film of a silver halide camera, and the more the number of pixels is, the more accurate the image becomes. The size is measured by a diagonal line of a quadrangle and is displayed in inch units such as a 1/3 inch CCD. The CCD has two imaging methods, an interline type and a frame transfer type. The interline type is commonly used in digital cameras. The interline type digital camera is composed of two parts, a light receiving part of a photodiode and a charge transfer part of a CCD part. Since the charge transfer section is shielded from light and only outputs the charges as a signal, the charges that are the image data of all pixels can be transferred at one time, and the shutter operation can be performed by the CCD alone. On the other hand, in the frame transfer type, C
The CD itself is a light-receiving portion, and its advantages include a high aperture ratio of nearly 100%, high sensitivity, and higher pixel count with lower processing accuracy than the interline type. On the other hand, as a demerit, the CCD area per pixel is larger than that of the interline type, and a mechanical shutter mechanism that blocks the incidence of light during CCD reading is required.

In the C-MOS image sensor, a pixel of a photosensitive portion is formed by a combination of a photodiode and a MOS transistor, and each pixel is connected to a horizontal and vertical shift register. The signal charge of each pixel is taken out to the output. The C-MOS image sensor is characterized in that when light is incident, it is photoelectrically converted by a photodiode, and signal charges corresponding to the intensity of light are accumulated with time. This element is also used in digital cameras and the like. .

When these elements are used in a digital camera built in (or externally attached to) a mobile phone, if the illuminating light of the subject is insufficient such as when photographing at night or in a dark room, light information is converted into an electric signal. Since it is a semiconductor element that is converted, a dark photographing result is obtained.

Therefore, there is a case where a strobe is used in order to enable photographing even when the exposure is insufficient such as at night or in a dark room. By firing the strobe, the subject can be captured as data with proper exposure. Note that strobe is a product name of Strobe Research Inc. in the United States, but is officially the name of Electronic Flash. As described above, the strobe is an indispensable device when the amount of light at the time of shooting is insufficient.

FIG. 5 is a view showing the structure of a xenon discharge tube according to the prior art. In the figure, 50 is a xenon discharge tube.
Reference numeral 1 denotes an outer tube of the xenon discharge tube. The xenon discharge tube 50 is a discharge tube that utilizes an electric discharge in a gas by enclosing the electrodes (cathode 53 and anode 54) in the arc tube 52, and then evacuating the arc tube 52 to put in the xenon gas 55. By applying a voltage between the electrodes 53 and 54,
A discharge is generated between the electrodes 53 and 54 to emit light. Here, the light emitting tube 52 and the outer tube 51 are glass tubes.
The light emission is a point light source having high brightness and color temperature, and radiates a continuous spectrum from ultraviolet to infrared. Since its spectrum distribution is close to that of sunlight, it becomes an ideal white light source. Moreover, the reason why the xenon discharge tube is used is that a very large peak illuminance can be obtained from a small average power in the strobe discharge.
In order to emit light from a xenon discharge tube, it is necessary to discharge a high voltage from one of the facing electrodes to the other to generate light. As a means to generate high voltage,
A charging element capable of charging electric charge and instantaneously discharging the charged electric charge to the xenon discharge tube of the light emitting part, for example, high voltage,
Use high-capacity, large-sized electrolytic capacitors. The distance M reached by the strobe is determined by the guide number GN that numerically represents the intensity of strobe light emission and the aperture value F of the brightness of the lens, and M = GN / F is established. For example, when the brightness of the lens is F2.8 in the GN4 strobe, the distance M at which the stroboscopic light emission reaches is 4 / 2.8 = about 1.4 m.

When a xenon discharge tube is used, in order to secure a distance at which light can be emitted, a high voltage and high capacity electrolytic capacitor of a charging element is used to secure a sufficient charge for a strobe power source, and maintenance is performed during consumable replacement. Need to think. In consideration of maintainability, a commercially available AA alkaline battery or the like is used as a power source for a strobe in a digital camera with a strobe or a disposable camera with a strobe. The size of a commercially available AA alkaline battery is Φ15 × 47 mm and the weight is about 24 g. As a power source for a strobe other than a dry battery, a lithium battery for a camera may be used to increase the number of times the strobe is used, but it is expensive and the number of times the strobe is used is about 1,000 times. The size of the lithium battery for the camera is Φ15.6
× 27mm, weight 12g, Φ17.1 × 34.5
mm and weight 16g.

FIG. 6 is a block diagram for explaining a configuration example of a portable telephone and an external strobe device thereof according to the prior art. In the figure, 60 is a strobe device and 80 is a part related to light emission on the portable telephone side. 2 (circuits for controlling the strobe device 60) are shown. The external strobe device 60 of the mobile phone is a strobe charging switch circuit 1
1, booster circuit 12, backflow prevention diode 13, electrolytic capacitor 14 of charging element, Zener diode 15, backflow prevention diode 16, switch stop circuit 17, charge completion LED 18, light emission switch circuit 19, switch time constant circuit 20, xenon discharge tube It is composed of an ON circuit 21, a xenon discharge tube 22, a dry battery power switch 61, a dry battery 62, and a connecting portion 63 for connecting to a mobile phone. On the other hand, the circuit 60 on the mobile phone side includes the flash light emission switch 35, the CPU 3
6 and a connecting portion 81 for connecting to an external strobe. The connecting portion 63 is a plug of an external strobe device, and the connecting portion 81 is a jack of a mobile phone. Xenon discharge tube O
The N circuit 21 has a xenon discharge tube 22 with a trigger voltage of 5 to 1
There is a trigger coil that applies about 0 KV.

The circuit operation up to light emission will be described with reference to FIG. Dry battery 62 is installed and dry battery power switch 61
When is turned on, the strobe charging switch circuit 11 is automatically turned on by detecting the battery voltage. This voltage is boosted by the booster circuit 12, and the electrolytic capacitor 14 as a charging element is charged with electric charge via the backflow prevention diode 13. When the voltage of the electrolytic capacitor 14 rises to a predetermined voltage for emitting light,
The Zener diode 15 becomes the Zener region, and the switch stop circuit 17 is turned on via the backflow prevention diode 16.
Let When the switch stop circuit 17 is turned on, the strobe charging switch circuit 11 is turned off to stop charging, and at the same time, the charge completion LED 18 is turned on. Therefore, at the same time that the predetermined charge for causing the electrolytic capacitor 14 to emit light is charged, the charge completion LED 18 lights up.

When it is desired to make the strobe emit light, the strobe light emission switch 35 is turned on. The CPU 36 detects that the flash light emission switch 35 is turned on, and the terminal e
Then, a strobe light emission ON signal is turned on via the terminal e of the connecting portion (jack) 81 and the terminal e of the plug 63 of the external strobe. The switch time constant circuit 20 delays the strobe light emission ON signal. This strobe light emission ON signal is added to the xenon discharge tube ON circuit 21, and 5 to 10K is output from the trigger coil in the circuit.
When a high voltage of V is applied to the xenon discharge tube 22 and the xenon gas is ionized, the xenon discharge tube 21 becomes conductive, and the electric charge charged in the electrolytic capacitor 14 is instantaneously supplied to the xenon discharge tube 22 to emit light. Become.

As described above, by firing the strobe and capturing the subject as data with proper exposure, it is possible to take a picture even in the case of underexposure such as at night or in a dark room. However, in order to make the xenon discharge tube emit enough light, it is necessary to secure a sufficient amount of charge for the high-voltage, high-capacity electrolytic capacitor, and for users who frequently use at night or in a dark room, the strobe power source is a dry battery. Therefore, the number of times of light emission is limited by the capacity of the dry battery, which is inconvenient.

As an example of calculation, when the rating of the electrolytic capacitor is 1,000 (μF) and 330 (V), the rating of the AA alkaline battery is 1.5 (V) and the capacity is 1,000 (mAh), the dry battery is Total electric energy is 1.5 (V)
× 1,000 (mAh) = 1.5 (Wh). When converted into Joule energy, it is 1.5 (Wh) x 6
0 (minutes) × 60 (seconds) = 5,400 (J). The energy consumption per one time of the electrolytic capacitor during charging and discharging is W = 1/2 CV ² (J), and W = 1/2 ×
1,000 (μF) × 330 (V) ² = 54.45 (J)
Becomes Therefore, the number of possible flashes in this calculation example is 5,
It becomes 400 (J) /5.45 (W) = 99.2 (times). Strictly speaking, there is a loss in the booster circuit 12, but if ignored, the number of times light can be emitted is about 99 times.

Although it is possible to increase the number of times of light emission by increasing the capacity of the dry battery, the capacity of the commercially available dry battery is proportional to the volume and weight of the dry battery. In the case of the external type that is connected by, since the volume and the weight of the dry battery are increased, the portability of the mobile phone becomes poor. Further, it is possible to assume that the dry battery is exhausted at the time of strobe light emission, and it may be possible to miss the opportunity to take a picture. It is necessary to newly purchase and replace the exhausted dry battery, and its maintenance is troublesome.

On the other hand, in a normal silver-salt camera or digital camera, there is a type in which a strobe device is built-in instead of the external strobe device as described above, but the strobe is made to emit light by using a dry battery as a power source for the strobe. When this is directly applied to the camera-equipped mobile phone, that is, even in the type (built-in type) in which the flash device is built in the mobile phone, the weight and volume of the mobile phone itself increase, and the portability deteriorates. Also, maintenance is troublesome like the external type.

[0016]

As described above, the conventional technique of using a commercially available dry battery as a power source for a flash device of a mobile phone causes a problem that the number of times the flash light can be emitted is small, or a dry battery is used. Even if the capacity is increased and the number of times of light emission is increased, the battery capacity and weight of the external type and the internal type are both increased, which causes a problem of poor portability of the mobile phone. In any case, it is possible to assume that the dry batteries are exhausted at the time of firing the flash, and it is possible to miss the opportunity to shoot, so it is necessary to purchase and replace the exhausted dry batteries, and its maintenance is troublesome. There is a problem. As described above, there are many problems in adopting a dry battery as a power source for strobe light emission.

The present invention has been made in view of the above situation, and is a mobile phone with a camera equipped with a strobe device, which is lightweight and has a small volume and which can substantially eliminate the limitation of the number of times of strobe light emission. Another object of the present invention is to provide a power supply circuit for a flash device in a camera-equipped mobile phone.

[0018]

In order to solve the above-mentioned problems, in the present invention, the power source for the strobe device of the camera-equipped mobile phone is supplied from the main body of the mobile phone. In another embodiment of the present invention, a constant voltage circuit and a semiconductor switch are provided as the power source for the strobe device. Further, in another embodiment of the present invention, a mounting detection means for detecting mounting of the external strobe device on the mobile phone by data is provided. The basic configuration in various embodiments of the present invention is realized by the following technical means.

A first technical means is a camera-equipped mobile phone having a built-in strobe device, wherein the power supply for the strobe device is the same as the power supplied to other devices in the mobile phone. It was done.

A second technical means is the same as the first technical means, wherein the strobe device has a high luminance L in its light emitting portion.
It is characterized by using ED.

A third technical means is a camera-equipped mobile phone to which a strobe device for emitting light by a high-intensity LED can be externally attached, and a power source for the strobe device is
It is characterized in that it is the same as the power supplied to other devices in the mobile phone.

A fourth technical means is the method according to any one of the first to third technical means, wherein the portable telephone is provided with an incoming LED for notifying a user of the outgoing call and / or the incoming call.
The incoming call LED is used as a light emitting portion of the strobe device.

A fifth technical means is the method according to any one of the first to fourth technical means, wherein the portable telephone is provided with a communication antenna, and the light emitting section of the strobe device is disposed at the tip of the communication antenna. It is characterized by being present.

A sixth technical means is the same as any one of the first to fifth technical means, wherein the strobe device is detachable from the portable telephone, and the portable telephone is provided with data transmission via the strobe device. It is characterized in that it has strobe mounting detection means for detecting mounting of the strobe device.

A seventh technical means is the method according to any one of the first to sixth technical means, wherein the power supply circuit of the strobe device is a constant voltage circuit for converting the power supply into a predetermined voltage, and the constant voltage circuit. And a semiconductor switch for controlling the output from the circuit to the light emitting portion of the strobe device.

An eighth technical means is a power supply circuit for a strobe device in a mobile phone with a digital camera according to any one of the first to seventh technical means.

[0027]

FIG. 1 is a block diagram showing a circuit for a strobe device and a configuration example of the strobe device in a mobile phone according to an embodiment of the present invention. The strobe function is realized by using a xenon discharge tube. It is a figure which shows the structural example in a case. A camera-equipped mobile phone according to an embodiment of the present invention has a built-in strobe device, and is used as a power source for a call, communication, screen display (often called a call, etc.) instead of a conventional dry battery. A rechargeable battery (for example, a lithium ion battery) shall be used. That is, the power supply for the strobe device is the same as the power supply for other devices in the mobile phone. A power supply circuit 30 for a strobe device illustrated in FIG. 1 (hereinafter, referred to as a power supply circuit for strobe) is a circuit for supplying power from a lithium ion battery 31, and includes a constant voltage circuit 32 and a constant voltage circuit 33. , FET (field effect transistor) switch circuit 34, strobe light emission switch 35, C
It may be considered as including the lithium ion battery 31 including the PU 36 and the connecting portion 37 connected to the strobe side circuit. The strobe power supply circuit 30 is a control circuit 80 for the strobe device 60 of the conventional example described with reference to FIG.
In the above, a rechargeable lithium-ion battery 31, a constant voltage circuit 33, and a FET switch circuit 34
It can be said that it was realized by adding. On the other hand, the circuit 10 on the strobe device side illustrated in FIG. 1 includes a strobe charging switch circuit 11, a booster circuit 12, a backflow prevention diode 13, a charging element electrolytic capacitor 14, a Zener diode 15, a backflow prevention diode 16, and a switch stop circuit 17. The charging completion LED 18, the light emission switch circuit 19, the switch time constant circuit 20, the xenon discharge tube ON circuit 21, and the xenon discharge tube 22. It can be said that the circuit 10 on the strobe device side is the same as the strobe device 60 of the conventional example described with reference to FIG. 6, except that the dry battery power switch 61 and the dry battery 62 are removed as its constituent elements.

The lithium ion battery 31 is an example of a rechargeable battery used as a power source for telephone calls and the like. Further, the constant voltage circuit 32 is a circuit for supplying a constant voltage to a circuit for telephone calls and the like, and the constant voltage circuit 33 is a circuit for supplying a constant voltage to a circuit for strobe light. The connecting portion 23 is a plug on the strobe side, and the connecting portion 37 is a jack on the mobile phone side. Further, in this configuration example, the voltage of the rechargeable lithium-ion battery 31 at the time of completion of charging is 4.2V, the voltage value of the constant voltage circuit 33 for the strobe is 3.0V, and the voltage of the lithium-ion battery 31 is 4.2V. Constant voltage circuit 33
Shows an example configured to output a constant voltage of 3.0 V. In addition, this strobe power supply circuit 30
The mobile phone provided with the device is provided with a constant voltage circuit 32 which is used as a power source for other circuits by setting the voltage of the lithium ion battery (for example, 4.2 V) to a predetermined voltage (for example, 3.0 V). Note that FIG. 1 shows a configuration example in which the strobe device can be taken out from the mobile phone in consideration of maintainability of the xenon discharge tube and separation of the manufacturing process.
The configuration of a mobile phone with a built-in strobe device is
It can be easily configured by connecting the terminal of the jack 37 of the mobile phone and the plug 23 of the strobe device in the main body of the mobile phone. On the contrary, the type in which the strobe device is externally attached can be easily configured by being connected outside the main body. Although I explained about what you can attach and detach the strobe, in consideration of the years of use of a general mobile phone, it is not possible to remove it by a user without a jack and a plug (or a strobe device that is permanently attached). May be adopted. Further, in an embodiment using an LED strobe described later, either a built-in strobe device or an external strobe device may be used. In addition, the xenon discharge tube 22
Is as described with reference to FIG.

The FET switch circuit 34 is an example of a switch circuit that is preferably provided in the case where the circuit on the strobe device side is made removable. In the case where the strobe charge ON signal is input from the CPU 36, the switch is turned on and set. It is a switch circuit for supplying the voltage of the voltage circuit 33 to the strobe side circuit 10 via the terminal a of the jack 37. The charging current for stroboscopic light emission is large because it is necessary to complete charging in a short time, and a FET switch circuit that allows control with less voltage drop in the resistance when it is ON and less heat generation due to the voltage drop is used. You may use the semiconductor switch of this. In addition, for example, the constant voltage circuit 3 is mechanically triggered by opening the lens cover on the camera side.
The voltage of 3 may be applied to the strobe charging switch circuit 11.

Further, strobe mounting detection means for detecting mounting of the strobe device by data transmission through the strobe device may be provided to detect the presence or absence of the strobe device. In the example of FIG. 1, the plug on the strobe device side is detected. At 23, the terminal b and the terminal c are connected, and at the terminal b of the jack 37, a plurality of bits for transmission of a distant distance are output in order from the CPU 36 at all times without signal deviation between the data lines. Downstream serial data is transmitted. CPU3
Reference numeral 6 is provided with a terminal c for inputting upstream serial data, and compares whether the downstream and upstream serial data match, and if they match, identifies that a strobe is attached. Since the terminal b of the jack 37 is open when the strobe is not attached, upstream serial data is not input to the CPU 36 via the terminal c of the jack 37. The CPU 36 identifies that the strobe is not attached because there is no upstream serial data, and does not shift to the next operation.

On the other hand, when the strobe is attached, the down serial data which is transmitted from the CPU 36 and which sequentially transmits a plurality of bits is connected to the terminal b and the terminal c of the plug 23, so that the terminal b and the terminal of the jack 37 are connected. It is input as upstream serial data to the CPU 36 via the terminal c and the terminal b and the terminal c of the plug 23. Therefore, the CPU
A line 36 identifies that the strobe device has been attached because the downlink and uplink serial data match.

After the strobe is attached and identified, the CPU 36
Strobe charging from terminal a to FET switch circuit 34
The N signal is output and the FET switch circuit 34 is turned on. When the FET switch circuit 34 is turned on, the output of the constant voltage circuit 33, which is the power source of the strobe device, is sent to the strobe charging switch circuit 11 via the terminal a of the jack 37.
0V is input.

The strobe charging switch circuit 11 is turned on by voltage detection, and the subsequent operation is the same as when using a dry battery, and the 3.0V voltage is boosted by the boosting circuit 12 and is a charging element via the backflow prevention diode 13. The electrolytic capacitor 14 is charged with electric charge. When the voltage of the electrolytic capacitor 14 rises to a predetermined voltage for emitting light, the Zener diode 15 enters the Zener region, and the switch stop circuit 17 is turned on via the backflow prevention diode 16. When the switch stop circuit 17 is turned on, the strobe charging switch circuit 1
When 1 is turned off, charging is stopped and at the same time, an LED (light emitting diode) 18 for notifying the completion of charging is turned on. That is, when the electrolytic capacitor 14 is charged with a predetermined charge for emitting light, the charging completion LED 18 is turned on.

When it is desired to make the light emitting section of the strobe device emit light, the strobe light emission switch 35 is turned on. Examples of this include a case where the user of the mobile phone pushes a button to turn it on, and a case where the exposure is insufficient to automatically turn it on. In the latter case, if the camera has an automatic exposure function, it is possible to automatically emit light by automatically turning on the flash emission switch 35 when it is determined that the exposure is insufficient. The CPU 36 detects that the strobe light emission switch 35 has been turned on, and outputs a strobe light emission ON signal from the terminal e to the light emission switch circuit 19 via the terminal e of the connecting portion (jack) 37 and the terminal e of the strobe plug 23. Turn it on. The switch time constant circuit 20 delays the strobe light emission ON signal. By applying this strobe light emission ON signal to the xenon discharge tube ON circuit 21,
As described in FIG. 6, the electric charge charged in the electrolytic capacitor 14 is instantaneously supplied to the xenon discharge tube 22 and emits light.

The electrolytic capacitor 14 is discharged by the light emitted from the strobe device. When the electrolytic capacitor 14 has no electric charge, the Zener diode 15 is turned off because the voltage across the electrolytic capacitor 14 falls below the Zener voltage. When the Zener diode 15 is turned off, the backflow prevention diode 16 and the switch stop circuit 17
When the LED turns off, the charge completion LED 18 also turns off
become. Therefore, the strobe charging switch circuit 11 is turned off.
The charging completion LED 18 is turned off until it is turned on from FF and the recharging operation starts and charging is completed. Further, the same recharging operation is performed even when there is no operation after charging and the electric charge charged in the electrolytic capacitor 14 is naturally discharged and the voltage drops.

As described above, the strobe attachment can be detected by the serial data, and the power source for the strobe device can be supplied from the main body of the mobile phone by having the constant voltage circuit and the semiconductor switch. That is, in a power supply circuit for a strobe device, a constant voltage circuit that converts the power supplied to another device (circuit) in the mobile phone into a predetermined voltage, and an output from the constant voltage circuit to the light emitting unit of the strobe device. By providing a semiconductor switch for controlling the light emitting device, it is possible to make the strobe device emit light from the main body of the mobile phone with a lighter weight and a smaller volume. Further, by including a strobe mounting detection unit that detects mounting of the strobe device by data transmission via the strobe device, it becomes possible to detect mounting of the strobe device.

As described above, by supplying the power source for strobe light emission from the lithium ion battery which is the power source for telephone conversation of the mobile phone, the number of strobe light emission is as follows.
The voltage can be restored by charging the lithium-ion battery of the mobile phone, the lithium-ion battery itself can emit light up to the number of charge / discharge cycles, and the storage volume and weight do not use dry batteries. Since it has only 3.0V constant voltage circuit and FET switch circuit for use, its volume and weight can be reduced significantly compared to dry batteries. Regarding the problem that the dry battery is exhausted and the opportunity to shoot is missed at the time of stroboscopic light emission, it can be used by charging if it is a lithium ion battery, so it is necessary to newly purchase and replace it like a dry battery No new purchases will occur until the end of the life. The capacity of the lithium-ion battery decreases when strobe light is emitted, but the capacity can be replenished by charging the battery when checking the battery level of the mobile phone. In this way, by supplying the power source for the strobe of the camera-equipped mobile phone from the main body battery such as a lithium-ion battery that is already present in the main body of the mobile phone, the strobe function becomes much easier to use.

FIG. 2 is a view showing the outer appearance of a mobile phone according to an embodiment of the present invention. In the figure, 40 shows an example of a mobile phone with a camera equipped with a strobe device. The mobile phone 40 illustrated here includes a communication antenna 41 and an incoming LED.
42, strobe device 43, digital camera 44, speaker 45, display screen 46, various button parts 47, microphone 48
And the strobe device 43 uses the xenon discharge tube 22 as its light emitting portion. The above-mentioned lithium ion battery is usually on the back side of the button portion 47, and the xenon discharge tube 22 emits light by using this battery as a power source.

FIG. 3 is a block diagram showing a configuration example of a circuit for a strobe device and a strobe device in a mobile phone according to another embodiment of the present invention. In the case where the strobe function is realized by using a high brightness LED. It is a figure which shows the structural example.
A mobile phone with a camera according to another embodiment of the present invention,
As a power source of the strobe device, a rechargeable battery (for example, a rechargeable lithium-ion battery) that is a power source for a call or the like is used instead of a conventional dry battery. Diode). In FIG. 3, reference numeral 30 is a power supply circuit for the strobe device, and 10 'is a circuit on the strobe device side. The camera-equipped mobile phone according to the present embodiment can be realized with a built-in strobe device or an externally-attached device. Similarly, the strobe device according to the present embodiment may be built in the camera-equipped mobile phone. , It should be external. Here, the xenon discharge tube 2
It will be explained that even if a single high brightness LED 26 or a plurality of high brightness LEDs 26 are used instead of the above, some circuit blocks can be changed.

Since the high-brightness LED does not require charging, the circuit block relating to the charging of the xenon discharge tube 22 is removed as compared with the circuit block described in FIG.
To the high-brightness LED 26 and the xenon discharge tube ON circuit 21 to the LED ON circuit 25, respectively. Further, the strobe charge ON signal output from the terminal a of the CPU 36 does not require charging in the case of a high-brightness LED. Therefore, the signal becomes a signal for turning on the FET switch circuit 34 in synchronization with pushing the strobe light emission switch 35. . The LED 18 is provided to inform the user that strobe light can be emitted, but may not be provided.

The irradiation distance of the strobe device using the high-brightness LED 26 in the present embodiment is about 0.5 m, assuming that the user holds the mobile phone in his hand and extends his hand to photograph himself. Therefore, the guide number GN is GN = 2.8 × 0.
5 = 1.4. The number of high-brightness chip surface-mounted LEDs for securing GN1.4 is about three. This number is a number that can be incorporated in the main body of the mobile phone without increasing the volume and weight of the mobile phone. Actually, the number of incoming LEDs mounted on the mobile phone is about three.

FIG. 4 is a view showing the appearance of a mobile phone according to another embodiment of the present invention. FIG. 4A shows an example of a mobile phone having a strobe device using an incoming call lamp.
(B) shows an example of a mobile phone in which a strobe device is provided as a communication antenna by 40 'and 40 ", respectively.

A portable telephone 40 'illustrated in FIG. 4 (A).
Is equipped with a communication antenna 41, a strobe device 43 ', a digital camera 44, a speaker 45, a display screen 46, various button parts 47, and a microphone 48. The strobe device 43' has high-intensity LEDs 26'a and 26'b. , 26'c are the light emitting portions. The above-mentioned lithium-ion battery is usually on the back side of the button portion 47, and the light emitting portion emits light using this battery as a power source. Also, the LEDs 26'a, 26'b, 26 'in the mobile phone 40' are
It is assumed that c also serves as an incoming LED that notifies the user of the outgoing call and / or the incoming call. By using the incoming call LED as the light emitting portion of the strobe device 43 ', the space and weight can be reduced. LED2 in this example
All of 6'a, 26'b, and 26'c are shown as being used also as an incoming call LED (incoming call lamp).
Only 6'a is used as an incoming LED, and LED 26 '
Alternatively, a, 26'b, 26'c may be used as a light emitting LED (two LEDs of LED 26'b, 26'c are dedicated for light emission). Of course, the LED 18 described in FIG. 3 may be used as the light emitting unit.

The mobile phone is provided with a communication antenna, and the light emitting portion (light emitting LED) of the strobe device is arranged at the tip of the communication antenna.
The mobile phone with a camera according to any one of 1. Figure 4 (B)
The mobile phone 40 ″ exemplified in FIG.
1 ", an incoming LED 42, a strobe device 43", a digital camera 44, a speaker 45, a display screen 46, various button parts 47, a microphone 48 are provided, and the strobe device 4 is provided.
3 ″ has a high-brightness LED 26 ″ as its light emitting portion and is arranged at the tip of the communication antenna 41 ″. The above-mentioned lithium ion battery is usually on the back side of the button portion 47, and this battery is used as a power source. As a result, the light emitting portion emits light. By providing the light emitting portion at the tip of the communication antenna 41 ″, the lens (image receiving portion) and the light emitting portion can be separated from each other, which also prevents red eye.

[0045]

According to the present invention, in a camera-equipped mobile phone equipped with a strobe device, the strobe device in the mobile phone is caused to emit light by using the power source of the mobile phone, so that the strobe device emits light with a small volume. It is possible to substantially eliminate the limitation of the number of times. The fact that it is possible to virtually eliminate the limit on the number of flashes is that a mobile phone is normally carried around while it is charged, and if the power supply of the mobile phone is uncharged, no photo is taken. It can be understood by considering that.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit example for a strobe device in a mobile phone according to an embodiment of the present invention and a configuration example of the strobe device.

FIG. 2 is a diagram showing an appearance of a mobile phone according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a circuit for a strobe device in a mobile phone according to another embodiment of the present invention and a configuration example of the strobe device.

FIG. 4 is a diagram showing an appearance of a mobile phone according to another embodiment of the present invention.

FIG. 5 is a diagram showing a structure of a xenon discharge tube according to a conventional technique.

FIG. 6 is a block diagram for explaining a configuration example of a conventional mobile phone and an external strobe device attached thereto.

[Explanation of symbols]

10, 10 ', 60 ... Strobe side circuit, 11 ... Strobe charge switch circuit, 12 ... Booster circuit, 13 ... Backflow prevention diode, 14 ... Charging element electrolytic capacitor, 15 ... Zener diode, 16 ... Backflow prevention diode, 17 ...
Switch stop circuit, 18 ... Charging completion LED, 19 ... Light emission switch circuit, 20 ... Switch time constant circuit, 21 ... Xenon discharge tube ON circuit, 22, 50 ... Xenon discharge tube, 2
3, 63 ... Strobe plug, 25 ... LED ON circuit, 26, 26'a, 26'b, 26'c, 26 "... L
ED, 30, 80 ... Cell phone side circuit, 31 ... Lithium ion battery, 32 ... Constant voltage circuit for circuits other than strobe, 33 ... Constant voltage circuit for strobe, 34 ... FET switch circuit, 35 ... Strobe light emission switch, 36 ... CP
U, 37, 81 ... Mobile phone jack, 40, 4
0 ', 40 "... mobile phone, 41,41" ... antenna,
42 ... Incoming call LED, 43, 43 ', 43 "... Strobe, 44 ... Digital camera, 45 ... Speaker, 46 ... Screen display section, 47 ... Button group, 48 ... Microphone, 51 ... Outer tube, 52 ... Arc tube, 53 ... Cathode, 54 ... Anode, 55 ... Xenon gas, 61 ... Dry battery power switch, 62 ... Dry battery.

Claims (8)

[Claims] 1. A mobile phone with a camera having a built-in strobe device, wherein the power supply for the strobe device is the same as the power supplied to other devices in the mobile phone. . 2. The mobile phone with camera according to claim 1, wherein the strobe device uses a high-intensity LED in a light emitting portion thereof. 3. A camera-equipped mobile phone to which a strobe device for emitting light by a high-intensity LED can be externally attached, wherein a power source for the strobe device is a power source supplied to another device in the mobile telephone. A mobile phone with a camera, which is also characterized by the same. 4. The mobile phone is provided with an incoming LED for informing a user of the outgoing call and / or the incoming call.
4. The camera-equipped mobile phone according to claim 1, wherein D is used as a light emitting unit of the strobe device. 5. The mobile phone comprises a communication antenna,
5. The camera-equipped mobile phone according to claim 1, wherein the light emitting unit of the strobe device is arranged at the tip of the communication antenna. 6. The strobe device is removable from the mobile phone, and the mobile phone has strobe mounting detection means for detecting mounting of the strobe device by data transmission via the strobe device. 6. The camera-equipped mobile phone according to claim 1. 7. The power supply circuit of the strobe device includes a constant voltage circuit for converting the power source into a predetermined voltage, and a semiconductor switch for controlling an output from the constant voltage circuit to a light emitting section of the strobe device. 7. The camera-equipped mobile phone according to claim 1, wherein the mobile phone has a camera. 8. A power supply circuit for a strobe device in a mobile phone with a digital camera according to claim 1.