JP2008211664A - Imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device capable of reducing power consumption during wireless communication without impairing functions as a camera. <P>SOLUTION: When wireless communication for transmitting a captured image to external equipment is started (S1), a transmission power control function sets transmission power to minimum power, and in this state, the imaging device starts transmitting a connection request signal to the external equipment. When the communication with the external equipment is successful, it is determined that the communication can be carried out with the transmission power and wireless communication using the power is performed thereafter. When the communication with the external equipment ends in failure, it is determined that the communication by the transmission power cannot be performed and the transmission power is made one-stage larger. In the state that the transmission power is made one-stage larger, the imaging device transmits the connection request signal to the external equipment. When there is a response from the external equipment, it is determined that the communication can be performed by the transmission power and wireless communication using the power is carried out thereafter, but when there is no response, the transmission power is made further one-stage larger and subsequent wireless communication is performed using the electric power at which the response comes from the external equipment. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is suitable for an imaging apparatus having a wireless communication function.

2. Description of the Related Art In recent years, an image pickup apparatus that is equipped with a wireless communication function such as a wireless LAN in a digital camera and transmits captured data via wireless communication has been commercialized. However, since a portable device such as a digital camera is a battery with a limited power source, there is a problem that the battery life is remarkably reduced when a function with large power consumption such as wireless communication is added.
Therefore, in order to solve such problems, for example, to reduce the peak value of current consumption, it is possible to set the transmission output, change the operation mode of the digital camera according to the set transmission output, There has been proposed an imaging apparatus that controls the amount of power supplied to the camera (Patent Document 1).
JP 2006-270537 A

However, in Patent Document 1, when wireless communication is performed, the operation of the camera is limited, and when wireless communication is performed, there is a problem that shooting cannot be performed and the function as a camera is not performed. It was.
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide an imaging apparatus capable of saving power during wireless communication without impairing the function as a camera.

In order to achieve the above object, the present invention according to claim 1 comprises a wireless communication means having a transmission means, a reception means, and a transmission power control means, and capable of performing wireless communication with an external device. In the imaging apparatus, control is performed so that wireless communication is performed with the external device by gradually increasing the transmission power of the transmission means by the transmission power control means from the start of wireless communication by the wireless communication means. Means are provided.
The present invention according to claim 2 further comprises battery remaining amount detecting means for detecting the remaining amount of the battery, wherein the control means is determined by the battery remaining amount detecting means that the remaining amount of the battery is sufficient. Controls the transmission power of the transmission means from the start of wireless communication to the maximum power, and when it is determined that the remaining battery level is low, the transmission power control means transmits the transmission of the transmission means from the start of wireless communication. Control is performed so that wireless communication is performed with the external device by gradually increasing power.
According to a third aspect of the present invention, there is provided a first power supply unit having a large output impedance, a second power supply unit having a smaller output impedance than the first power supply unit, and any one of the first and second power supply units. A power source discriminating unit that discriminates whether the second power source unit is connected by the power source discriminating unit from the start of wireless communication. When the transmission power of the transmission means is controlled to the maximum power and when it is determined that the first power supply unit is connected, the transmission power of the transmission means is gradually increased by the transmission power control means from the start of wireless communication. Then, control is performed so that wireless communication is performed with the external device.

The present invention according to claim 4 further comprises switching means for turning ON / OFF the transmission power control means, and the control means controls the transmission power control from the start of wireless communication when the transmission power control means is ON. The transmission power of the transmission means is gradually increased by means to control so that wireless communication is performed with the external device. When the transmission power control means is OFF, the transmission is started from the start of wireless communication. The transmission power of the means is controlled to the maximum power.
The present invention according to claim 5 includes a memory means, and the control means can gradually increase the transmission power of the transmission means by the transmission power control means to perform wireless communication with the external device. The transmission power is stored in the memory means, and during normal camera operation, the transmission power of the transmission means is controlled to the maximum power from the start of wireless communication, and the power consumption is higher than that during normal camera operation. In this case, the transmission power stored in the memory means is controlled.
According to a sixth aspect of the present invention, the control means performs wireless communication with the external device when power is turned on, and transmits to the memory means transmission power that can be wirelessly communicated with the external device. It is characterized by storing.
According to a seventh aspect of the present invention, the control means stores, in the memory means, transmission power at which wireless communication with the external device can be performed during initial communication.

  According to the present invention, when the wireless communication is started by the control means, the transmission power is gradually increased by the transmission power control means, and the subsequent wireless communication is performed using the transmission power that can be wirelessly communicated with the external device. That is, it is possible to save power in the imaging apparatus having the wireless communication means by avoiding wireless communication with uselessly large transmission power.

Hereinafter, embodiments of the imaging apparatus of the present invention will be described.
[First Embodiment]
FIG. 1 is a block diagram illustrating an internal configuration of an imaging apparatus according to the first embodiment of the present invention. Note that the imaging apparatus of this embodiment has a wireless communication function for performing wireless communication with an external device.
An image to be captured is formed on a CCD (Charge Coupled Device) 2 surface by a lens 1, and image data is converted into electrical data by the CCD 2. The electrical data is AD-converted by an F / E (front end) 3 that performs signal processing from the CCD 2 and is signal-processed by the DSP 4. The CCD 2 is driven so as to be synchronized with the DSP 4 by a clock of a TG (timing generator) 5.
The SDRAM 6 is used to read / write the AD-converted raw data and signal processed data of the CCD output. An EEPROM (memory means) 7 is used to store data such as adjustment values. In addition, the memory card 8 is used for storing a photographed image. The LCD 9 is used for displaying an image to be captured or displaying an image recorded on a memory card.

Also, the DSP (control means) 4 generates evaluation values such as AF, AE, and white balance (in the case of AF, for example, an integrated value for each frequency component of the image, etc.), performs the calculation thereof, and combines with the motor 11 is controlled. Further, the DSP 4 as the control unit lacks the function of setting parameters for the F / E 3 and the like, the function of processing input from the operation switch 12 that is an operation from the photographer, and the brightness at the time of photographing. Sometimes, it has a function of controlling the flash unit 13 and a function of controlling the sound processing unit 16 that records sound with the microphone 14 and reproduces it with the speaker 15.
In addition, the power supply unit 17 (generally a battery but an AC adapter may be used) is converted into a voltage necessary for each system via a DC-DC converter 18 and supplied. The wireless communication module 19 is used to output imaging data and information to an external device. The wireless communication module 19 includes an antenna 20 for communicating with an external device.

FIG. 2 is a block diagram showing the internal configuration of the wireless communication module.
The wireless communication module 20 illustrated in FIG. 2 includes a wireless controller 21, an Amp (amplifier) 22, a receiving unit 23, a transmitting unit 24, an Amp (amplifier) 25, an output power control unit 26, and a changeover switch 27.
The wireless controller 21 exchanges data with the DSP 4 in response to a command from the DSP 4, and received data received by wireless communication from an external device is received by the antenna 20 and then output to the Amp 22 via the changeover switch 27. The reception data amplified by Amp 22 is processed by the reception unit 23 and passed to the wireless controller 21.
On the other hand, transmission data to be transmitted to an external device by wireless communication is transferred from the wireless controller 21 to the transmission unit 24, processed by the transmission unit 24, amplified by Amp 25, and transmitted from the antenna 20 via the changeover switch 27. The At that time, the amplification factor of Amp 25 is determined by the output power control unit 26, and the transmission power from the antenna 20 can be changed.

FIG. 3 is a flowchart showing a wireless communication process according to the first embodiment of the present invention. Note that the wireless communication processing described below will be described as being realized when the DSP 4 as the control unit controls the wireless controller 21 of the wireless communication module 19.
When wireless communication such as transmitting a captured image to an external device is started (S1), first, transmission power is set to a minimum by a transmission power control function (S2). In this state, transmission of a connection request signal from the imaging device to the external device is started (S3). Here, if there is a reply from the external device, that is, if communication with the external device is possible (“Y” in S4), it is determined that communication is possible with the transmission power, and then wireless communication is performed with that power (S5). . On the other hand, if there is no response from the external device, that is, if communication with the external device is not possible ("N" in S4), it is determined that communication cannot be performed with the transmission power.
If the transmission power is not maximum (“N” in S6), the transmission power is increased by one level (S7). Thereafter, the process returns to step S3, and a connection request signal is transmitted from the imaging apparatus to the external device. On the other hand, when the transmission power is maximum (“Y” in S6), wireless communication is executed with the power (S5).

As described above, in the first embodiment, the transmission request signal is transmitted from the imaging apparatus to the external device with the transmission power set to the minimum, and if there is no response from the external device, the transmission power is increased by one level. In this state, a connection request signal is transmitted from the imaging device to the external device, and if there is a response from the external device, it is determined that communication is possible with the transmission power, then wireless communication is performed with that power, and there is no response. For example, the one-stage transmission power is further increased, and the subsequent wireless communication is performed with the power returned from the external device.
The transmission power is divided by dividing the maximum transmission power and the minimum transmission power into several stages, and the interval may not be equal or even. Moreover, since it takes time until the optimum transmission power is obtained if it is divided too finely, an appropriate size is desirable.
As described above, in the first embodiment, at the start of wireless communication, the transmission power is gradually increased by the transmission power control function, and the subsequent wireless communication is performed with the transmission power that enables wireless communication with the external device. did. In other words, wireless communication is not performed with uselessly large transmission power. As a result, it is possible to save power in the imaging apparatus having a wireless communication function.

[Second Embodiment]
Next, an imaging apparatus according to the second embodiment of the present invention will be described.
FIG. 4 is a block diagram showing an internal configuration of an imaging apparatus according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same site | part as FIG. 1, and description is abbreviate | omitted. The internal configuration of the wireless communication module 19 is the same as that shown in FIG.
The imaging apparatus shown in FIG. 4 includes a remaining battery level detection unit 28 that detects the remaining battery level of the power supply unit 17 and outputs the detection result of the remaining battery level detection unit 28 to the DSP 4. The DSP 4 outputs the detection result of the battery remaining amount detection unit 28 to, for example, the wireless controller 21 of the wireless communication module 19. The wireless controller 21 performs wireless communication at the maximum power from the start of communication when the battery of the power supply unit 17 is sufficient, and transmits power at the start of wireless communication when the battery of the power supply unit 17 is low. The transmission power is gradually increased by the control function, and control is performed so that the subsequent wireless communication is performed with the transmission power capable of wireless communication with the external device.

FIG. 5 is a flowchart showing wireless communication processing according to the second embodiment.
Note that the wireless communication processing described below is described as being realized by the DSP 4 controlling the wireless controller 21 of the wireless communication module 19.
When wireless communication is started such that an image captured by the imaging device is transmitted to an external device (S11), first, the remaining battery level is detected by the remaining battery level detection unit 28 (S12), and the remaining battery level is sufficient. It is determined whether or not there is (S13). Here, when the remaining battery level is sufficient (“Y” in S13), the transmission power is maximized by the transmission power control function (S14), and wireless communication is executed (S15).
On the other hand, when the remaining battery level is low (“N” in S13), the transmission power control function sets the transmission power to the minimum (S16), and in this state, the imaging apparatus transmits a connection request signal to the external device. Start (S17). If there is a reply from the external device, that is, if communication with the external device is possible (“Y” in S18), it is determined that communication is possible with the transmission power, and then wireless communication is performed with the power. To do.
On the other hand, if there is no reply from the external device, that is, if communication with the external device is not possible ("N" in S18), it is determined that communication cannot be performed with the transmission power. If the transmission power is not maximum (“N” in S19), the transmission power is increased by one step (S20). Thereafter, the process returns to step S17, and a connection request signal is transmitted from the imaging apparatus to the external device. On the other hand, when the transmission power is maximum (“Y” in S19), wireless communication is executed with the power (S15).

  As described above, in the second embodiment, the battery remaining amount detection unit 28 that detects the remaining battery level of the power supply unit 17 is provided, and when the remaining battery level of the power supply unit 17 is sufficient, the maximum is greater than at the start of communication. When performing wireless communication with power and when the remaining battery level is low, at the start of wireless communication, the transmission power control function gradually increases the transmission power, and the subsequent wireless communication with the transmission power that can be performed wirelessly with the external device. I tried to do it. Thereby, the battery life of the power supply part 17 can be extended and it becomes possible to aim at the power saving of the imaging device which has a wireless communication function.

[Third Embodiment]
Next, an imaging apparatus according to the third embodiment of the present invention will be described.
FIG. 6 is a block diagram illustrating an internal configuration of an imaging apparatus according to the third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same site | part as FIG. 1, and description is abbreviate | omitted. The internal configuration of the wireless communication module 19 is the same as that shown in FIG.
The imaging apparatus shown in FIG. 6 is configured such that a battery (first power supply unit) 31 having a large output impedance and a battery (second power supply unit) 32 having a low output impedance can be used as a power supply unit. Yes. The battery determination unit 33 determines whether the connected battery is a battery (first power supply unit) 31 having a large output impedance or a battery (second power supply unit) 32 having a lower output impedance than the battery 31. The determination result is output to the DSP 4. The DSP 4 turns on one of the switches 34 and 35 and turns off the other based on the discrimination result of the battery discrimination unit 33. Thereby, the energy of the 1st power supply part 31 or the 2nd power supply part 32 is supplied to the DC-DC converter 18, and an imaging device operate | moves.
Further, when the DSP 4 determines that a battery having a small output impedance is used by the battery determination unit 33, the DSP 4 performs wireless communication with the maximum power from the start of communication. On the other hand, when it is determined by the battery determination unit 33 that a battery with a large output impedance is being used, the transmission power control function gradually increases the transmission power at the start of wireless communication, and wireless communication with an external device can be performed. Control is performed to perform subsequent wireless communication with the transmission power.

FIG. 7 is a flowchart showing wireless communication processing according to the third embodiment.
Note that the wireless communication processing described below is described as being realized by the DSP 4 controlling the wireless controller 21 of the wireless communication module 19.
When wireless communication is started such that an image captured by the imaging device is transmitted to an external device (S21), battery determination is first performed in the battery determination unit 33 (S22). If the output impedance of the battery is small (in S23) “Y”), the transmission power is maximized by the transmission power control function (S24), and wireless communication is executed (S25).
On the other hand, when the output impedance of the battery is large ("N" in S23), the transmission power control function sets the transmission power to the minimum (S26), and in this state, the connection request signal is transmitted from the imaging device to the external device. (S27). If there is a reply from the external device, that is, if communication with the external device is possible ("Y" in S28), it is determined that communication is possible with the transmission power, and thereafter wireless communication is performed with the power. Communicate.
On the other hand, if there is no reply from the external device, that is, if communication with the external device is not possible ("N" in S28), it is determined that communication cannot be performed with the transmission power. If the transmission power is not maximum (“N” in S29), the transmission power is increased by one step (S30). Thereafter, the process returns to step S27, and a connection request signal is transmitted from the imaging apparatus to the external device. On the other hand, when the transmission power is maximum (“Y” in S29), wireless communication is executed with that power (S25).

  As described above, in the third embodiment, two types of batteries, that is, the battery (first power supply unit) 31 having a large output impedance and the battery (second power supply unit 32) having a small output impedance are configured to be usable. And when the battery discrimination | determination part 33 discriminate | determines that the battery with small output impedance is used, radio | wireless communication is performed with the maximum electric power from the time of communication start. Also, when it is determined that a battery with a large output impedance is being used, at the start of wireless communication, the transmission power is gradually increased by the transmission power control function, and the subsequent wireless communication is performed with the transmission power that can be wirelessly communicated with the external device. I tried to do it. Thereby, the battery life of the 1st and 2nd power supply parts 31 and 32 can be extended, and it becomes possible to aim at the power saving of the imaging device which has a wireless communication function.

[Fourth Embodiment]
Although illustration is omitted, for example, if it is configured so that the user (user) can turn on / off transmission power control by operating the operation unit according to a menu screen or the like, that is, transmission power control If switching means for switching ON / OFF is provided, when transmission power control is ON, transmission power can be gradually increased by the transmission power control function at the start of wireless communication, enabling wireless communication with external devices. When the transmission power control is OFF and the transmission power control is OFF, imaging with a wireless communication function that saves power as necessary by performing wireless communication with maximum power from the start of communication. An apparatus can be provided.

[Fifth Embodiment]
In the imaging apparatus of the present embodiment, at the start of wireless communication, the transmission power is gradually increased by the transmission power control function, and the transmission power capable of wireless communication with an external device is stored in a memory unit such as SDRAM 6. Then, wireless communication is performed with the maximum power during normal camera operation, and power saving is achieved by performing wireless communication with the transmission power stored in the SDRAM 6 when the current consumption mode is higher than during normal camera operation. Therefore, it is possible to provide an imaging apparatus having a wireless communication function. Note that the memory means is not limited to the SDRAM 6, and an EEPROM 7 or a memory card 8 can also be used.
Further, the mode in which the power consumption is larger than that during normal camera operation refers to a state in which a motor such as a zoom is operated or a state in which flash charging is performed.
The transmission power stored in the SDRAM 6 is the transmission power that allows wireless communication with the external device when the power is turned on and the wireless communication with the external device, or the initial communication with the external device. Transmission power that can be wirelessly communicated is considered.

1 is a block diagram illustrating an internal configuration of an imaging apparatus according to a first embodiment of the present invention. It is the block diagram which showed the internal structure of the radio | wireless communication module. It is the flowchart which showed the radio | wireless communication process which concerns on 1st Embodiment. It is the block diagram which showed the internal structure of the imaging device which concerns on 2nd Embodiment. It is the flowchart which showed the radio | wireless communication process which concerns on 2nd Embodiment. It is the block diagram which showed the internal structure of the imaging device which concerns on 3rd Embodiment. 10 is a flowchart illustrating wireless communication processing according to a third embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Lens, 2 ... CCD, 3 ... F / E, 4 ... DSP, 5 ... TG, 6 ... SDRAM, 7 ... EEPROM, 8 ... Memory card, 9 ... LCD, 11 ... Motor, 12 ... Operation switch, 13 ... Strobe unit, 14 ... microphone, 15 ... speaker, 16 ... audio processing unit, 17 ... power supply unit, 18 ... DC converter, 19 ... wireless communication module, 20 ... antenna, 20 ... wireless communication module, 21 ... wireless controller, 23 ... Receiving unit, 24 ... transmitting unit, 22, 25 ... Amp, 26 ... output power control unit, 27 ... switch, 28 ... remaining battery level detection unit, 31 ... first power supply unit, 32 ... second power supply unit, 33 ... Battery discriminating part 34 ... switch

Claims (7)

In an imaging apparatus including a wireless communication unit that has a transmission unit, a reception unit, and a transmission power control unit and can perform wireless communication with an external device.
Control means for controlling so that wireless communication is performed with the external device by gradually increasing the transmission power of the transmission means by the transmission power control means from the start of wireless communication by the wireless communication means. An imaging apparatus characterized by the above. Battery level detection means for detecting the remaining battery level,
The control means controls the transmission power of the transmission means to the maximum power from the start of wireless communication and determines the remaining battery level when the remaining battery level detection means determines that the remaining battery level is sufficient. When it is determined that there is little, the transmission power control means gradually increases the transmission power of the transmission means from the start of wireless communication and controls to perform wireless communication with the external device. The imaging apparatus according to claim 1, wherein: A first power supply unit having a large output impedance, a second power supply unit having a smaller output impedance than the first power supply unit, and a power supply for determining whether one of the first and second power supply units is connected A discriminating means,
The control means controls the transmission power of the transmission means to the maximum power from the start of wireless communication and determines the first power supply when the power supply determination means determines that the second power supply unit is connected. When the wireless communication unit is determined to be connected, the transmission power control unit gradually increases the transmission power of the transmission unit from the start of wireless communication so that the wireless communication is performed with the external device. The imaging apparatus according to claim 1, wherein: Switching means for turning ON / OFF the transmission power control means,
When the transmission power control means is ON, the control means gradually increases the transmission power of the transmission means by the transmission power control means from the start of wireless communication to perform wireless communication with the external device. The imaging apparatus according to claim 1, wherein when the transmission power control unit is OFF, the transmission power of the transmission unit is controlled to a maximum power from the start of wireless communication. Comprising a memory means,
The control means gradually increases the transmission power of the transmission means by the transmission power control means, and stores the transmission power capable of wireless communication with the external device in the memory means. During operation, the transmission power of the transmission means is controlled to the maximum power from the start of wireless communication, and when the power consumption is higher than that during the normal camera operation, the transmission power stored in the memory means is used. The imaging apparatus according to claim 1, wherein the imaging apparatus is controlled as follows.   6. The control unit performs wireless communication with the external device when power is turned on, and stores transmission power in the wireless communication with the external device in the memory unit. The imaging device described in 1.   The imaging apparatus according to claim 5, wherein the control unit stores, in the memory unit, transmission power that allows wireless communication with the external apparatus during initial communication.

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