JP5912692B2 - Portable electronic devices - Google Patents

Description

  The present invention relates to a portable electronic device equipped with a radiation sensor, and is suitably used for, for example, a mobile phone equipped with a radiation sensor or PDA (Personal Digital Assistants).

  The radiation sensor has a characteristic of erroneous detection in an environment with a lot of vibration. For this reason, many portable radiation measuring instruments have a relatively large volume and a large weight.

  As a prior art document related to the present invention, Japanese Patent Application Laid-Open No. 2008-147711 (Patent Document 1) is known. The portable terminal described in this document includes a vibration sensor, and automatically sets whether to accept or reject an incoming call based on information related to the vibration of the own device detected by the vibration sensor.

JP 2008-147711 A

  The inventors of the present invention are considering mounting a radiation sensor on a portable electronic device such as a cellular phone or PDA (Personal Digital Assistants). Such portable electronic devices with radiation detectors have not been commercialized so far and are not publicly known.

  Since mobile phones, PDAs, etc. are usually carried around at all times, there is an advantage that radiation can be easily measured when a device with a radiation detector is put into practical use. However, since this main electronic device is made small and lightweight for portability, there is a problem that the detection accuracy of radiation is lowered.

  The present invention has been made in consideration of the above-described problems, and an object thereof is to suppress a decrease in radiation detection accuracy due to vibration of the own device in a portable electronic device including a radiation sensor. Other problems and novel features will become apparent from the description of the present specification and the accompanying drawings.

  A portable electronic device according to an embodiment of the present invention includes a radiation sensor, an acceleration sensor, and a control unit. The control unit continuously detects the displacement due to the vibration of the own machine with the lapse of time by the acceleration sensor, and indicates the intensity of the vibration and the degree of the vibration within a predetermined time until the current time using the detected displacement. The first evaluation value is calculated continuously over time. And a control part makes the output signal of the radiation sensor obtained in the effective time slot | zone when the time slot | zone except at least the time slot | zone when the 1st evaluation value exceeded predetermined | prescribed 1st tolerance was made into an effective time slot | zone. The radiation dose is calculated based on

  Preferably, the control unit continuously calculates a second evaluation value representing the degree of vibration intensity and the number of vibrations of the own device from the start time of radiation detection by the radiation sensor to the current time as time elapses. . In this case, the control unit stops the detection of radiation by the radiation sensor when the second evaluation value exceeds a predetermined second allowable value.

  Preferably, the first evaluation value is an integrated value of the magnitude of displacement due to the vibration of the own device within a predetermined time until the current time.

  Preferably, the second evaluation value is an integrated value of the magnitude of displacement due to vibration of the own device from the start time of radiation detection by the radiation sensor to the current time.

  Preferably, the portable electronic device further includes a display unit for displaying images and character information, and a speaker for outputting sound. When the first evaluation value exceeds the first allowable value, the control unit notifies the user by a display on the display unit or an output sound from the speaker.

  Preferably, when the second evaluation value exceeds the second allowable value, the control unit notifies the user by a display on the display unit or an output sound from the speaker.

Preferably, the portable electronic device is a portable terminal having a telephone function.
Preferably, the portable electronic device further includes a vibrator capable of notifying that an incoming call has arrived. In the case where the control unit is set to notify the incoming call by vibration of the vibrator, the vibrator is not operated even when the incoming call is received during the radiation measurement by the radiation sensor.

  Preferably, in a case where the control unit is set to notify the incoming call by voice, during the radiation measurement by the radiation sensor, the ringtone is set to a predetermined volume or less, or the ringtone is not emitted. To do.

  According to said embodiment, the fall of the detection accuracy of the radiation by the vibration of an own machine can be suppressed.

It is a block diagram which shows an example of the hardware constitutions of the mobile telephone 1 by one Embodiment. It is a block diagram which shows the functional structure of the part regarding a radiation measurement in the mobile telephone 1 of FIG. It is a figure for demonstrating concretely operation | movement of the integrated value calculation part 24, the comparison part 25, and the data invalidation part 21 of FIG. It is a flowchart which shows the procedure which measures a radiation with the mobile telephone 1 with a portable radiation sensor of this Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, a mobile phone (mobile communication terminal) such as a smartphone provided with a radiation sensor will be described as an example. However, the application target of the present invention is not limited to a mobile phone. A radiation sensor can be mounted on a PDA (Personal Digital Assistants) that does not have a communication function, and a device in which an acceleration sensor is mounted on a portable radiation measuring instrument is one embodiment of the present invention.

  In the following description, the same or corresponding parts are denoted by the same reference numerals, and the description thereof may not be repeated.

[Overall configuration of mobile phone 1]
FIG. 1 is a block diagram illustrating an example of a hardware configuration of a mobile phone 1 according to an embodiment. A cellular phone 1 includes a central processing unit (CPU) 2, a random access memory (RAM) 3, a read only memory (ROM) 4, a memory 5, a communication device 6, an antenna 7, a microphone 8, a speaker 9, and audio. A signal processing circuit 10, a display unit 12, an input unit 11, a vibrator 13, an acceleration sensor 14, and a radiation sensor 15 are included.

  The CPU 2 controls the overall operation of the mobile phone 1 by executing programs stored in the ROM 4 and the memory 5. The RAM 3 is used as the main memory of the CPU 2.

  The memory 5 is configured by an EEPROM (Electrically Erasable Programmable Read-Only Memory) such as a flash memory or a hard disk. The memory 5 stores data output from the CPU 2. Particularly in this embodiment, the memory 5 stores data based on the output signal of the acceleration sensor 14 and data based on the output signal of the radiation sensor 15.

  The communication device 6 performs wireless communication of an audio signal and a data signal via the antenna 7 based on a command from the CPU 2.

  The audio signal processing circuit 10 performs AD (Analog-to-Digital) conversion on the audio signal detected by the microphone 8 and performs signal processing such as encoding and noise removal on the converted digital audio signal. The audio signal processing circuit 10 further performs predetermined signal processing on the digital signal to be acoustically output and outputs it to the speaker 9. Unlike the case of FIG. 1, the CPU 2 may execute the functions of the audio signal processing circuit 10 based on a program without providing the audio signal processing circuit 10.

  The display unit 12 is configured by a liquid crystal display panel or the like, and displays character information and an image based on a command from the CPU 2.

  The input unit 11 includes hardware keys for the user to perform input operations such as numbers and characters on the mobile phone 1. Alternatively, when the mobile phone 1 is a smartphone or the like, the input unit 11 may be configured to include a touch panel integrated with the display unit 12. In this case, since the user performs most of the input operation via the touch panel, only a small number of keys such as a power key and a volume key are provided as hardware keys, and keys for numbers and characters are not provided.

  The vibrator 13 vibrates based on a command from the CPU 2 and is used, for example, when an incoming call is transmitted to the user.

  The acceleration sensor 14 is a sensor that detects acceleration. For example, the acceleration sensor 14 has a weight supported by a beam structure, and detects and outputs the amount of displacement of the weight as a change in capacitance or piezoresistance. The displacement amount of the weight body is proportional to the acceleration acting on the acceleration sensor 14. Usually, a mobile phone such as a smartphone is provided with a triaxial acceleration sensor for detecting the attitude of the mobile phone.

  The output of the acceleration sensor is a sum of displacement due to vibration and displacement due to gravitational acceleration. Since displacement due to gravity acceleration changes more slowly than displacement due to vibration, removing displacement due to gravity acceleration (equivalent to passing through a low-pass filter) is eliminated by removing the average value of output within a predetermined period. Can do. As a result, the displacement amount due to the vibration of the mobile phone 1 can be detected by the acceleration sensor. For example, in the case of a three-axis acceleration sensor, displacements Δx, Δy, and Δz due to vibrations in three directions can be obtained. Since the mobile phone is usually provided with an acceleration sensor, there is an advantage that it is not necessary to add a dedicated circuit for detecting vibration.

  The radiation sensor 15 outputs a pulse signal when detecting radiation. For example, the radiation sensor 15 includes a silicon PIN photodiode to which a bias voltage is applied in the reverse direction. In this case, a pulsed current signal is generated by electron-hole pairs generated when radiation passes through the depletion layer. The radiation sensor 15 of FIG. 1 further includes an amplifier that amplifies the pulse signal and an AD converter that performs AD (Analog-to-Digital) conversion on the amplified signal.

  The radiation sensor 15 configured as described above is characterized by being easily affected by impacts and vibrations. For example, a pseudo pulse is generated when the stray capacitance of the amplifier changes due to vibration. If this pseudo pulse is erroneously detected as a pulse by radiation, an error is caused in the measurement result of radiation.

  As will be described in detail below, in the case of the mobile phone 1 according to the present embodiment, the intensity and number of vibrations of the own device are monitored by an acceleration sensor. And in the time slot | zone when the grade of a vibration exceeds an allowable level, a detection error is suppressed by invalidating the output of a radiation sensor.

[About radiation measurement]
FIG. 2 is a block diagram showing a functional configuration of a part related to radiation measurement in the mobile phone 1 of FIG.

  With reference to FIGS. 1 and 2, the CPU 2 has functions as an integrated value calculation unit 24, a comparison unit 25, a data invalidation unit 21, a counting unit 22, a dose calculation unit 23, and a system control unit 20. These functions are realized when a program for radiation measurement is executed by the CPU 2.

  Based on the output of the acceleration sensor 14, the integrated value calculation unit 24 continuously detects the displacement due to the vibration of the own device over time. Then, the integrated value calculation unit 24 continuously calculates a first evaluation value representing the intensity of vibration and the degree of vibration within a predetermined time until the current time using the detected displacement as time passes. To do.

  In the case of the present embodiment, the first evaluation value is an integrated value obtained by integrating the magnitude of displacement due to the vibration of the own device within a predetermined time until the current time for each predetermined time step. In addition, it is good also as an evaluation value by integrating | accumulating the peak value (maximum value) of the magnitude | size of a displacement, and good also considering the number of peaks (number of local maximum points) more than a reference value as an evaluation value.

  Here, the magnitude of the displacement is given as an absolute value of the detected displacement amount in the case of a uniaxial acceleration sensor. Since positive displacement and negative displacement occur in the same degree in the displacement caused by vibration, only the positive displacement may be taken out as a representative value, and the magnitude of the displacement may be taken out, or the absolute value of the positive and negative values may be taken out. Also good. In the case of a triaxial acceleration sensor, if Δx, Δy, and Δz are obtained as displacements in three directions, the magnitude of the displacement is given as the square root of the sum of squares of Δx, Δy, and Δz. Alternatively, the maximum value of the absolute values of Δx, Δy, and Δz may be set as the magnitude of the displacement.

  The integrated value calculation unit 24 further uses the detected displacement due to the vibration of the own device to obtain a second evaluation value representing the intensity of vibration of the own device and the degree of the number of vibrations from the start time of the radiation measurement to the current time. calculate. The second evaluation value is an integrated value of the magnitude of vibration displacement from the start time of radiation measurement to the current time. Also in this case, the peak value (maximum value) of the magnitude of displacement may be integrated, or the number of peaks (the number of local maximum points) equal to or greater than the reference value may be integrated. The second evaluation value is used to determine whether or not radiation measurement is possible.

  The comparing unit 25 compares the first evaluation value (integrated value) calculated by the integrated value calculating unit 24 with the first allowable value, and outputs the comparison result to the data invalidating unit 21.

  The data invalidation unit 21 invalidates the output of the radiation sensor 15 obtained in the invalid time period in which the first evaluation value exceeds the first allowable value and the predetermined time before and after the first evaluation value. This invalid time zone is excluded from the measurement time of radiation.

  The counting unit 22 counts the number of pulses included in the output signal of the radiation sensor 15 obtained in the effective time zone excluding the invalid time zone.

  The dose calculation unit 23 calculates the radiation dose corresponding to the number of pulses counted by the counting unit 22 and its statistical error.

  The system control unit 20 displays the radiation dose and statistical error calculated by the dose calculation unit 23 on the display unit 12. Further, the system control unit 20 displays a message on the display unit 12 when the first and second evaluation values (integrated values) exceed the first and second allowable values, and the speaker 9 outputs a warning sound. As a result, the user of the mobile phone 1 is careful to suppress vibration, so that the radiation measurement accuracy can be increased.

  FIG. 3 is a diagram for specifically explaining operations of integrated value calculation unit 24, comparison unit 25, and data invalidation unit 21 of FIG. FIG. 3 shows, in order from the top, the waveform of the output signal of the radiation sensor 15, the time waveform of the vibration displacement based on the output of the acceleration sensor 14, and the integrated value of the magnitude (absolute value) of the displacement. For simplicity, the acceleration sensor is a uniaxial acceleration sensor.

  Referring to FIG. 3, for example, assuming that the current time is t2, integrated value calculation unit 24 in FIG. 2 shows the magnitude of displacement due to vibration obtained within predetermined time TM1 (from time t1 to time t2) until current time t2. Accumulate the absolute value. Integration of the magnitude of the displacement within the predetermined time TM1 is continuously performed as time elapses. As a result, an integrated value calculation result as shown in the graph of FIG. 3 is obtained.

  2 compares the integrated value calculated at each time with the allowable value A1. The data invalidation unit 21 in FIG. 2 displays an invalid time zone TM2 (from time t3 to time t6) obtained by adding a predetermined time before and after the time zone (from time t4 to time t5) when the integrated value exceeds the allowable value A1. Exclude from radiation measurement time. As a result, only the true pulses 31 and 32 excluding the pseudo pulse 32 due to vibration can be counted, so that the radiation dose detection accuracy can be improved.

  FIG. 4 is a flowchart showing a procedure for measuring radiation by the mobile phone 1 with the mobile radiation sensor of the present embodiment.

  The measurement procedure of FIG. 4 is started by an input operation of a user who requests radiation measurement (YES in step S1).

  In response to the request to start radiation measurement, the system control unit 20 (CPU 2) in FIG. 2 turns off the vibrator 13 (step S2). Accordingly, when the incoming call is set to be notified by the vibration of the vibrator 13, the vibrator 13 can be prevented from operating even if the incoming call is received. Further, when the system control unit 20 (CPU 2) is set to notify the incoming call by voice, the ringtone is set to a predetermined volume or less or does not emit the ringtone (step S3). . As a result, vibration of the mobile phone 1 during radiation measurement can be reduced, so that the radiation detection accuracy can be increased.

  After that, the system control unit 20 (CPU 2) turns on the acceleration sensor 14 (step S4) and starts measuring radiation by turning on the radiation sensor 15 (step S5). In the case of a mobile phone such as a smartphone, the acceleration sensor 14 is often always on in order to detect the attitude of the own device.

  When the measurement of radiation is started, the integrated value calculation unit 24 in FIG. 2 integrates the magnitude of displacement due to vibration within a predetermined time until the current time based on the output signal of the acceleration sensor 14 (step S6). ). If the calculated integrated value (first evaluation value) is equal to or less than the allowable value A1 (YES in step S7), the data invalidation unit 21 treats the output signal of the radiation sensor 15 at the current time as valid. When a pulse is detected in the valid output signal, the counting unit 22 counts the number of pulses. The dose calculation unit 23 calculates the radiation dose corresponding to the number of pulses counted by the counting unit 22 and its statistical error (step S10). The calculated radiation dose and statistical error are displayed on the display unit 12 (step S11).

  On the other hand, when the integrated value (first evaluation value) calculated by the integrated value calculating unit 24 exceeds the allowable value A1 (NO in step S7), the system control unit 20 sends a message to the display unit 12. The user is notified by displaying or outputting a warning sound from the speaker 9 (step S14). In this case, the data invalidation unit 21 treats the output signal of the radiation sensor 15 at the current time as invalid (step S15).

  Furthermore, the integrated value calculation unit 24 calculates an integrated value (second evaluation value) of the magnitude of displacement due to vibration from the radiation measurement start time to the current time (step S16). As a result, when the integrated value (second evaluation value) exceeds the allowable value A2, the system control unit 20 (CPU 2) displays a message on the display unit 12 or outputs a sound from the speaker 9. To notify the user that measurement is impossible (step S18). In this case, the CPU 2 stops the radiation measurement. Thereafter, remeasurement may be automatically executed.

  The above measurement of radiation is repeated until the statistical error of the radiation dose is within the reference value (YES in step S12). When the statistical error falls within the reference value, the CPU 2 ends the radiation measurement by turning off the radiation sensor 15 (step S13). When the radiation measurement is completed, it is desirable to display a measurement completion message on the display unit 12 or output from the speaker 9. Since the radiation measurement is completed based on the statistical error value, the radiation measurement can be completed in a short time when the radiation dose is relatively high.

  The embodiment disclosed this time must be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Mobile telephone, 2 CPU, 5 Memory, 9 Speaker, 12 Display part, 13 Vibrator, 14 Acceleration sensor, 15 Radiation sensor, 20 System control part, 21 Data invalidation part, 22 Counting part, 23 Dose calculation part, 24 Integration Value calculation unit, 25 comparison unit.

Claims (8)

A radiation sensor;
An acceleration sensor;
A control unit,
The control unit continuously calculates a first evaluation value representing the magnitude of vibration and the number of times of vibration within a predetermined time until the current time based on the detection value of the acceleration sensor as time passes. ,
The control unit, when the time zone excluding at least a time zone in which the first evaluation value exceeds a predetermined first allowable value is an effective time zone, the radiation sensor obtained in the effective time zone. Calculate the radiation dose based on the output signal,
The control unit continuously calculates a second evaluation value representing the intensity of vibration and the number of times of vibration from the start time of radiation detection by the radiation sensor to the current time, with the passage of time,
The control unit is a portable electronic device that stops detection of radiation by the radiation sensor when the second evaluation value exceeds a predetermined second allowable value.   2. The portable electronic device according to claim 1, wherein the first evaluation value is an integrated value of a magnitude of displacement due to vibration of the own device within a predetermined time until the current time.   3. The portable electronic device according to claim 2, wherein the second evaluation value is an integrated value of the magnitude of displacement due to vibration of the own device from a start time of radiation detection by the radiation sensor to a current time. The portable electronic device is:
A display for displaying image and text information;
A speaker for outputting sound;
4. The control unit according to claim 1, wherein when the first evaluation value exceeds the first allowable value, the control unit notifies the user by a display on the display unit or an output sound from the speaker. Item 1. A portable electronic device according to item 1. The portable electronic device is:
A display unit for displaying image and text information and a speaker for outputting sound;
The control unit according to any one of claims 1 to 3, wherein when the second evaluation value exceeds the second allowable value, the control unit notifies the user by a display on the display unit or an output sound from the speaker. Item 1. A portable electronic device according to item 1.   The portable electronic device according to claim 4 or 5, wherein the portable electronic device is a portable terminal having a telephone function. It also has a vibrator that can notify you of incoming calls,
7. The control unit according to claim 6, wherein the control unit is configured to notify the incoming call by vibration of the vibrator, and the vibrator is not operated even when the incoming call is received during radiation measurement by the radiation sensor. The portable electronic device described.   In the case where the control unit is set to notify the incoming call by voice, during the radiation measurement by the radiation sensor, the ring tone is set to a predetermined volume or less, or the ring tone is not emitted. The portable electronic device according to claim 6 or 7.

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