JP2014099073A - Electronic apparatus, control method of the same, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus that includes a new user interface not relying on a touch panel, by solving the problem in which: electronic apparatuses today have been highly functionalized, and which may result in an insufficient display area to display icons and the like.SOLUTION: An electronic apparatus includes: a sound wave generation unit that emits sound waves having a predetermined frequency to a space; a sound wave detection unit that detects the emitted sound wave; a change detection unit that detects a change in sound pressure in the sound wave detected by the sound wave detection unit; and a determination unit that determines the presence of movement of an object within a predetermined range on the basis of the change in the sound pressure.

Description

  The present invention relates to an electronic device, a control method thereof, and a program.

  Electronic devices such as mobile phones and smartphones often include a touch panel as an operation device. A user operates an electronic device by touching an icon or the like displayed on a display device such as a liquid crystal panel.

  In addition to the touch panel, there is an electronic device that accepts an operation by a user by pressing a hardware key. Alternatively, there is an electronic device that detects a user operation by disposing an acceleration sensor or the like inside the electronic device and detecting a change in posture of the housing of the electronic device. More specifically, the user operates the electronic device by tilting or shaking the housing of the electronic device.

  Here, Patent Document 1 discloses a technology in which when a hand is held over a mobile phone, the sensor detects the approach and emits information about time and the like from a speaker. Furthermore, Patent Document 2 discloses a technique for detecting a hand movement or the like by transmitting a plurality of signals and using the impulse response of the signal reflected by a human hand or the like. .

JP 2005-045655 A Special table 2011-517584 gazette

  Each disclosure of the above prior art document is incorporated herein by reference. The following analysis was made by the present inventors.

  As described above, a touch panel is often used as an operation device for electronic equipment. In that case, it is necessary to display an icon etc. required for a user's operation on the display of an electronic device. In recent years, there has been a remarkable increase in functionality in electronic devices, and there are cases where display areas capable of displaying icons and the like are not sufficient. That is, in the interface using the touch panel, the display area is often insufficient for information that needs to be provided to the user.

  In addition, it may be possible to compensate for the shortage of display area with hardware keys, but for electronic devices such as smartphones, there is a limit to the size of the housing, and it is difficult to add hardware keys from the viewpoint of mounting area It is in. Furthermore, it is difficult for an interface that detects a user operation by tilting an electronic device to coexist with an operation using a touch panel, and does not compensate for a shortage of display area.

  Under the circumstances as described above, an electronic device having a new user interface that does not depend on a touch panel, a control method thereof, and a program are desired.

  The technique disclosed in Patent Document 1 is a technique that detects the approach of an object by detecting the reflection time of a sound wave, and provides information to the user according to the result. A new user interface is provided. It is not provided. The technique disclosed in Patent Document 2 is a technique for detecting the movement and position of a human hand based on measurement of an impulse response. The purpose is to detect the movement of a relatively large object, and it is not suitable for the operation of a smartphone or the like.

  According to the first aspect of the present invention, a sound wave generation unit that radiates sound waves having a predetermined frequency to space, a sound wave detection unit that detects the emitted sound waves, and sound waves detected by the sound wave detection unit An electronic device is provided that includes a change detection unit that detects a change in pressure and a determination unit that determines whether or not an object has moved within a predetermined range based on the change in the sound pressure.

According to a second aspect of the present invention, there is provided a control method for an electronic device comprising: a sound wave generation unit that radiates sound waves having a predetermined frequency into space; and a sound wave detection unit that detects the emitted sound waves. And a step of detecting a change in sound pressure of a sound wave detected by the sound wave detection unit, and a step of determining whether or not an object has moved within a predetermined range based on the change in sound pressure. A method is provided.
In addition, this method is tied to the specific machine called an electronic device provided with a sound wave generation part and a sound wave detection part.

According to a third aspect of the present invention, the present invention is implemented in a computer that controls an electronic device that includes a sound wave generator that radiates sound waves having a predetermined frequency to a space and a sound wave detector that detects the emitted sound waves. A process for detecting a change in sound pressure of a sound wave detected by the sound wave detection unit, and a process for determining whether or not an object has moved within a predetermined range based on the change in sound pressure. A program to be executed is provided.
This program can be recorded on a computer-readable storage medium. The storage medium can be non-transient such as a semiconductor memory, a hard disk, a magnetic recording medium, an optical recording medium, or the like. The present invention can also be embodied as a computer program product.

  According to each aspect of the present invention, an electronic device that contributes to providing a new user interface that does not depend on a touch panel, a control method thereof, and a program are provided.

It is a figure for demonstrating the outline | summary of one Embodiment. It is an example of the perspective view which shows the whole electronic device 1 which concerns on 1st Embodiment. It is a figure which shows an example at the time of visually recognizing the electronic device 1 from the side surface. It is a figure which shows an example of sound pressure space distribution of the sound wave radiated | emitted from the speaker. It is a figure which shows an example of sound pressure space distribution of the sound wave radiated | emitted from the speaker. It is a figure which shows an example of sound pressure space distribution of the sound wave radiated | emitted from the speaker. 1 is a diagram illustrating an example of an internal configuration of an electronic device 1. 6 is a diagram illustrating an example of signal processing in a digital signal processing unit 80. FIG. It is an example of the output waveform of the microphone 30. FIG. 3 is a diagram illustrating an example of an output waveform of a microphone 30. FIG. FIG. 4 is a diagram illustrating an example of an output waveform of a multiplier 310. 4 is a diagram illustrating an example of an output waveform of a digital signal processing unit 80. FIG. It is a figure which shows another example of the signal processing in the digital signal processing part. It is a figure which shows another example of the signal processing in the digital signal processing part. FIG. 4 is a diagram illustrating an example of an output waveform of a multiplier 310. 3 is a flowchart illustrating an example of an operation of the electronic device 1.

  First, an outline of an embodiment will be described with reference to FIG. Note that the reference numerals of the drawings attached to the outline are attached to the respective elements for convenience as an example for facilitating understanding, and the description of the outline is not intended to be any limitation.

  As described above, an electronic device including a new user interface that does not depend on a touch panel is desired.

  Therefore, an electronic device 100 shown in FIG. 1 is provided as an example. The electronic device 100 detects a change in sound pressure in the sound wave detected by the sound wave detection unit 102 that detects the emitted sound wave, the sound wave generation unit 101 that radiates a sound wave having a predetermined frequency to the space, And a determination unit 104 that determines whether or not an object has moved within a predetermined range based on a change in sound pressure.

  The electronic device 100 associates the sound pressure of the sound wave detected by the sound wave detection unit 102 with a change in accordance with the movement of an object existing around the electronic device 100 and the user's operation. That is, when the user moves a finger in the vicinity of the sound wave generation unit 101 or the sound wave detection unit 102 of the electronic device 100, the sound pressure of the sound wave detected by the sound wave detection unit 102 changes. In the electronic device 100, such a change in sound pressure of sound waves is used to detect movement in an operation unit (for example, a user's fingertip) for operating the electronic device 100. As a result, the electronic device 100 including a new user interface that does not depend on the touch panel can be provided.

  Hereinafter, specific embodiments will be described in more detail with reference to the drawings.

[First Embodiment]
The first embodiment will be described in more detail with reference to the drawings.

  The electronic device 1 according to the present embodiment provides an interface for detecting a user operation by utilizing the fact that the sound field is disturbed when an object (for example, a user's fingertip) placed in the sound field moves. More specifically, a sound wave having a predetermined frequency is radiated from a speaker to the space, and the sound wave is collected by a microphone and converted into an electric signal. Furthermore, an envelope of sound pressure (envelope curve) is calculated by performing signal processing on the converted electrical signal. Based on the time change of the envelope, the user's operation is specified. The user operates the electronic device 1 by placing a finger near the electronic device 1 (referred to as a home position in the following description) and moving the finger placed at the home position.

  FIG. 2 is an example of a perspective view showing the entire electronic apparatus 1 according to the present embodiment. The three-dimensional coordinate system in the subsequent drawings including FIG. 2 is as shown in the illustrated coordinate axes.

  The electronic apparatus 1 includes a display device 10, a speaker 20, and a microphone 30. The speaker 20 corresponds to the sound wave generation unit 101 described above, and the microphone 30 corresponds to the sound wave detection unit 102. The housing of the electronic device 1 is provided with a sound hole (not shown) so that sound waves can be emitted from the speaker 20. Furthermore, a sound hole corresponding to the microphone 30 is also provided so that a sound wave can be collected by the microphone 30. As the speaker 20, a normal speaker (for example, an electrodynamic speaker or a piezoelectric speaker) provided for the electronic device 1 to emit a beep sound or the like can be used. Alternatively, a speaker independent from such a normal speaker may be used. Further, the speaker 20 may emit ultrasonic waves (sound waves belonging to a frequency band higher than the audible band) including an ultrasonic transducer.

  The microphone 30 is disposed on the side surface of the electronic device 1, but is not intended to limit the mounting position of the microphone 30. The microphone 30 may be disposed on a surface other than the side surface. Alternatively, it is not intended to limit the number of microphones mounted on the electronic device 1 to one. There may be a plurality of microphones mounted on the electronic apparatus 1.

  A region indicated by a dotted line in FIG. In the electronic device 1, the user's fingertip is placed at the home position 200 and the finger placed at the home position 200 is scheduled to be moved.

  FIG. 3 is a diagram illustrating an example when the electronic device 1 is viewed from the side. 3, the same components as those in FIG. 2 are denoted by the same reference numerals, and the description thereof is omitted. 2 and 3, it can be understood that the home position 200 is slightly above the speaker 20 and does not allow the user's finger and the electronic device 1 to be in contact with each other.

  Next, prior to the description of the specific configuration of the electronic device 1, when an object placed on the ultrasonic sound field moves, the user's operation can be detected using the fact that the sound field is disturbed as a time waveform. Will be explained.

FIG. 4 is a diagram illustrating an example of a sound pressure space distribution of sound waves emitted from the speaker 20. In addition, the conditions at the time of calculating the sound wave shown in FIG. 4 can be as follows, for example.
The size of the electronic device 1 is 5 cm (X direction) × 10 cm (Y direction) × 1 cm (Z direction).
The origin of the position vector is the center of the surface on which the speaker 20 is mounted.
The frequency of sound waves emitted from the speaker 20 is 20 kHz.
The display related to the spatial distribution of sound waves is performed on a 20 cm × 20 cm ZX plane, and sound waves are calculated by the boundary element method.
Moreover, the code | symbol 201 of FIG. 4 shows one surface of the electronic device 1 in which the center point of the sound hole of the speaker 20 used as the origin of a three-dimensional coordinate system exists. Reference numeral 202 denotes a surface on which the microphone 30 mounted on the side surface of the electronic device 1 and the center point of the sound hole are present.

  In FIG. 4, the upper direction (Z direction) is the display surface of the electronic device 1, and the sound pressure of the sound wave emitted from the speaker 20 toward the upper direction is arranged like a surface opposite to the cusp of the cardioid. It turns out that it is a spatial distribution. FIG. 4 is a contour diagram (contour map) showing a spatial distribution of a real-time waveform of sound pressure. The difference in color shading in FIG. 4 includes information on the phase and amplitude shown in the following equation (1).

なお、ωは角速度、ｋは波形番号、ｔは時刻を示す。 Here, the velocity potential in the position coordinate vector I of the sound hole of the speaker 20 is Φ ₀ (I). Also, if the Green function that is the solution of the Helmholtz equation ((∇ ² + k ² ) φ = −δ (RI)) in the coordinate position vector R is G ₀ (R), the velocity potential in the sound hole coordinates of the microphone 30 Can be represented by the following formula (1). However, since the sound hole of the microphone 30 is very small, the sound hole of the microphone 30 is simplified to a specific point, and the integration on the sound hole surface is omitted.

Note that ω is an angular velocity, k is a waveform number, and t is time.

なお、ρは空気密度である。 From the velocity potential calculated based on the equation (1), the sound pressure P ₀ (R, t) at the coordinates of the sound hole of the microphone 30 can be calculated by the following equation (2).

Note that ρ is the air density.

  By referring to Equation (2), it can be seen that the sound pressure is proportional to the time change of the velocity potential.

  FIG. 5 is a diagram illustrating an example of a sound pressure space distribution of sound waves emitted from the speaker 20. FIG. 5 shows the spatial distribution of sound pressure when the object 203 assuming a finger is placed at a position shifted by 5 cm in the X direction and 5 cm in the Z direction from the center of the sound hole of the speaker 20 arranged as shown in FIG. It is a figure which shows the change of. Referring to FIG. 5, it can be understood that the change in sound pressure in the direction opposite to the direction in which the display surface faces (the negative direction of the Z axis) and the X direction is irregular. In the following description, the disturbance of the spatial distribution of sound pressure due to the presence of an object around the electronic device 1 is referred to as modulation of the sound pressure spatial distribution.

  FIG. 6 is a diagram illustrating an example of a sound pressure space distribution of sound waves emitted from the speaker 20. FIG. 6 shows the spatial distribution of sound pressure when the object 204 assuming four fingers excluding the thumb is arranged at a position shifted by 5 cm in the X direction and 5 cm in the Z direction from the center of the sound hole of the speaker 20. Showing change.

When FIG. 5 is compared with FIG. 6, it can be confirmed in FIG. 6 that the modulation of the sound pressure spatial distribution occurs more remarkably. The green function is different between the case of FIG. 4 where the modulation of the sound pressure spatial distribution does not exist and the case of FIGS. 5 and 6 where the modulation of the sound pressure spatial distribution exists. Therefore, if the Green function in FIGS. 5 and 6 is G (R, I), the velocity potential under the conditions in FIGS. 5 and 6 can be expressed by the following equation (3).

  Here, FIGS. 5 and 6 illustrate the modulation of the sound pressure spatial distribution when an object assuming a finger is stopped at a predetermined position. However, actually, the user operates the electronic device 1 by moving a finger. This means that the position of the stationary object moves in FIGS. 5 and 6. That is, in the above formula (3), since the Green function changes with time, the Green function is not a function that depends only on the position (with only the position as a parameter) but a function with time as a parameter.

In consideration of such circumstances, the following expressions (4) and (5) are obtained when the velocity potential and the sound pressure when the position of the object (finger position) changes are re-represented.

  Since the movement of the user's finger when operating the electronic device 1 cannot be regarded as a sine wave, the spatial coordinates and the time parameters in the time-dependent Green function G (R, I, t) cannot be separated. Therefore, equations (4) and (5) cannot be further simplified. In the following description, the change in the sound pressure time waveform collected by the microphone 30 is referred to as the modulation of the sound pressure time waveform.

As described above, the Green function changes depending on time. However, the factor is the movement of the user's finger. From the viewpoint of the frequency of sound waves emitted from the speaker 20 (for example, 20 kHz), the change rate (or time derivative) of the movement of the user's finger is very small and can be regarded as a gradual change. Therefore, the value of the second term in the above equation (5) is a very small value. As a result, equation (5) can be approximated as equation (6).

  Referring to equation (6), the modulation of the sound pressure time waveform can be regarded as AM modulation (amplitude modulation) by an integration factor that also depends on time.

  Based on the change in the sound pressure time waveform, it is determined that the user has placed the finger at a predetermined position and moved the finger under the physical conditions described above. The electronic device 1 calculates the envelope of the electrical signal converted by the microphone 30 and uses the calculated envelope to change the global time waveform, that is, the Green function G (R, The presence or absence of a change in I, t) is detected.

  FIG. 7 is a diagram illustrating an example of the internal configuration of the electronic apparatus 1. The electronic apparatus 1 includes a display device 10, a speaker 20, a microphone 30, an operation device 40, a tone sound generation unit 50, an amplifier 60, an AD (Analog To Digital) converter 70, and a digital signal processing unit 80. And a control unit 90.

  The electronic apparatus 1 includes a display device 10 such as a liquid crystal panel, for example. The electronic device 1 includes a speaker 20 and a microphone 30. The electronic device 1 includes an operation device 40 such as a touch panel, for example. The tone sound generator 50 generates a tone sound having a frequency higher than 20 kHz. The tone sound generated by the tone sound generation unit 50 is amplified to an appropriate power by the amplifier 60 and radiated as a sound wave by the speaker 20. The AD converter 70 converts an analog signal output from the microphone 30 into a digital signal.

  The digital signal processing unit 80 performs signal processing on the digital signal output from the AD converter 70, thereby specifying the user's operation based on the sound pressure time waveform caused by the user moving his / her finger. A logic signal is output to the control unit 90. The digital signal processing unit 80 corresponds to the change detection unit 103 and the determination unit 104 described above.

  The control unit 90 controls each unit shown in FIG. In addition, the control unit 90 provides the user with functions and operations corresponding to the operation according to the logic signal output from the digital signal processing unit 80. Note that the digital signal processing unit 80 and the control unit 90 can also be realized by a computer program that causes a computer mounted on the electronic device 1 to execute processing, which will be described in detail later, using hardware thereof.

  FIG. 8 is a diagram illustrating an example of signal processing in the digital signal processing unit 80.

The digital signal processing unit 80 receives the digital signal converted by the AD converter 70 as an input signal. The digital signal output from the AD converter 70 includes a time-series column vector (S ₀ = (s ₀ 1, s ₀ 2,... S ₀ m) of the signal (20 kHz tone sound) collected by the microphone 30. )) And a time-series column vector of noise components (N ₀ = (n ₀ 1, n ₀ 2,... N ₀ m)). However, m is a positive integer (hereinafter the same).

  The band pass filter 301 filters the digital signal received by the digital signal processing unit 80. As a result, only a signal having a desired frequency (here, a tone sound of 20 kHz) passes through the bandpass filter 301.

  The Hilbert transformer 302 performs a Hilbert transform on the signal that has passed through the bandpass filter 301. A column vector of the signal that has passed through the bandpass filter 301 is represented as a signal column vector S, and a Hilbert-transformed signal column vector is represented as h (S).

The complex analysis signal conversion & standard norm calculator 303 generates a complex analysis signal from the signal sequence vector S that has passed through the bandpass filter 301 and the Hilbert-transformed signal sequence vector h (S). Further, the complex analysis signal conversion & standard norm calculator 303 calculates the standard norm of the complex analysis signal. The complex analytic signal generated by the complex analytic signal conversion & standard norm calculator 303 is expressed by the following equation (7), and the standard norm can be expressed by the equation (8).

S ² and h (S) ² are column vectors generated by calculating the square of each component of the column vector. The standard norm output from the complex analysis signal conversion and standard norm calculator 303 corresponds to the envelope of the sound pressure in the sound wave collected by the microphone 30.

  The band pass filter 304 filters the output signal of the complex analysis signal conversion & standard norm calculator 303. When the Hilbert transformer 302 is to be realized using an FIR (Finite Impulse Response) filter with a small number of taps, an ideal Hilbert transform is performed over the entire range of positive and negative Nyquist frequencies of the discrete Fourier transform component in the digital signal sequence vector. Is difficult to do. That is, since a transition region in which the phase is not ± π / 2 occurs, a slight tone sound component (here, 20 kHz) is included in addition to the envelope component. The band pass filter 304 removes such tone components.

  Furthermore, the band-pass filter 304 can remove a DC component in the envelope. The band-pass filter 304 determines its stop frequency so as to pass only the envelope. For example, the stop frequency on the low frequency side is set to 10 Hz, and the stop frequency on the high frequency side is set to 30 Hz.

  Here, a path formed by the band pass filter 304 from the Hilbert transformer 302 is referred to as a signal processing path. On the other hand, a path formed by the noise detector 309 from the band stop filter 306 is referred to as a noise processing path.

  The delay unit 305 adjusts the timing of the signal supplied from each of the signal processing path and the noise processing path. The delay unit 305 adjusts the number of delay samples therein so that the signal processed by the signal processing path and the signal processed by the noise processing path are supplied to the multiplier 310 at the same timing.

  As described above, the path starting from the band stop filter 306 is a path for executing processing related to noise. The band stop filter 306 extracts a noise component that cannot be removed by the band pass filter 301. The extracted noise is expressed as a noise component vector N.

  The standard norm calculator 307 calculates a standard norm | N | of the noise component vector N. The low pass filter 308 removes the envelope component of the sound wave from the standard norm | N | of the noise component vector N calculated by the standard norm calculator 307.

The noise component after the low-pass filter 308 removes the envelope component _sets the standard norm of the noise component vector N as the standard norm | N | _lpf . Noise detector 309, the standard norm | accepting _lpf | N. The noise detector 309 executes processing shown in the following formula (9). Note that a column vector output from the noise detector 309 is referred to as a column vector W.

The noise detector 309 outputs “0” when the standard norm | N | _lpf exceeds a certain threshold value n _th . The noise detector 309 outputs “1” when the standard norm | N | _lpf is smaller than the threshold value n _th . The noise detector 309 calculates the process shown in Equation (9) for each sample of the standard norm | N | _lpf .

  Multiplier 310 multiplies the output of delay unit 305 and the output of noise detector 309 for each sample. This indicates that when “0” is output from the noise detector 309 (when noise is present), the value output from the multiplier 310 is “0”. Note that a column vector output from the multiplier 310 is represented as a column vector X.

The signal output from the multiplier 310 is converted into a rectangular wave by a threshold value determination unit and a low-pass filter in order to determine by a logical value (0/1) whether or not the user has finally performed an operation. More specifically, it is converted into a rectangular wave by the low-pass filters 311 and 313 and the waveform shapers 312 and 314. The waveform shaper 312 performs the process shown in Expression (10). The waveform shaper 314 executes the process shown in Expression (11). The waveform shapers 312 and 314 execute the processing shown in the equations (10) and (11) for each sample. Note that a column vector output from the waveform shaper 312 is referred to as a column vector Y. A column vector output from the waveform shaper 314 is represented as a column vector Z.

Referring to equations (10) and (11), it can be understood that the waveform shaper 312 compares the absolute value of the column vector X with a threshold value and outputs a logical value (0/1) based on the comparison result. . The waveform shaper 314 is the same. The threshold values used by the waveform shapers 312 and 314 are x _th and y _th , respectively.

  FIG. 9 is an example of the output waveform of the microphone 30. FIG. 9 shows the output of the microphone 30 when an object such as a user's finger is not present in the predetermined space. The predetermined space is, for example, the inside of a sphere having a diameter of about 10 cm with the speaker 20 as the center.

  FIG. 10 is a diagram illustrating an example of an output waveform of the microphone 30. FIG. 10 shows the output of the microphone 30 when the user performs an operation of pressing a switch (a movement of a finger pressing down from above in a predetermined space).

  Referring to FIG. 9, the envelope of the output waveform of the microphone 30 is constant. On the other hand, referring to FIG. 10, fluctuations in the envelope can be confirmed during the period from time T01 to T02 when the user's finger moves.

  FIG. 11 is a diagram illustrating an example of an output waveform of the multiplier 310. The waveform shown in FIG. 11 corresponds to the waveform shown in FIG. 10, and shows the output of the multiplier 310 when the finger is moved under the same conditions as in FIG. Note that because there is a delay in each processing block, the time axes of FIG. 10 and FIG. 11 do not match.

  Here, the envelope of the signal sequence vector S is calculated in the complex analysis signal conversion & standard norm calculator 303. Further, since the direct current component is removed from the envelope by the action of the band pass filter 304, the reference value of the output of the multiplier 310 is “0”. Further, referring to FIG. 11, it can be seen that the output of the multiplier 310 has positive and negative amplitudes in the vertical axis direction. Therefore, when the user moves his / her finger, the change in sound pressure of the sound wave collected by the microphone 30 corresponds to the upper and lower waveforms in the multiplier 310 shown in FIG.

In FIG. 11, the alternate long and short dash line parallel to the horizontal axis indicates the threshold value x _th in Equation (10). In the waveform shaper 312, when the column vector X output from the multiplier 310 exceeds the threshold value x _th , a logical value “1” is output. Further, since the column vector X is input to the waveform shaper 312 after the minute variation of the column vector X output from the multiplier 310 is removed by the low-pass filter 311, the logical value “ The output of “1” continues.

  FIG. 12 is a diagram illustrating an example of an output waveform of the digital signal processing unit 80. The waveform in FIG. 12 is a waveform after passing through the low-pass filter 313 and the waveform shaper 314. That is, the digital signal processing unit 80 finally outputs a rectangular wave. Thus, the logical value “1” is output only during the period when the user's finger moves.

  The control unit 90 receives a logical value “1” from the digital signal processing unit 80. The control unit 90 recognizes a user operation from the received logical value “1”, and executes a process assigned to the operation.

  Note that the electronic device 1 may include a plurality of microphones. In such a case, the digital signal processing unit 80 may generate envelopes for sound waves obtained from the respective microphones and execute processing for specifying user operations in parallel.

  In the electronic device 1, the configuration of the digital signal processing unit 80 has been described on the assumption that noise is included in the sound wave collected by the microphone 30. However, if the electronic device 1 is used in an environment where noise components need not be considered, the configuration of the digital signal processing unit 80 can be simplified.

  FIG. 13 is a diagram illustrating another example of signal processing in the digital signal processing unit 80.

  If it is not necessary to consider the noise component, as shown in FIG. 13, the noise processing path (band stop filter 306 to noise detector 309), delay device 305, and multiplier 310 in FIG. 8 can be deleted. Furthermore, depending on the environment in which the electronic device 1 is used, the low-pass filter 308 and the like can be deleted.

  Alternatively, the waveform shaper and the low-pass filter for making the output of the multiplier 310 a rectangular wave are not limited to two stages as shown in FIG. It is also possible (see FIG. 14). FIG. 14 shows an example in which the waveform shaper and the low-pass filter are one stage.

The waveform shaper 312 can also have two threshold values. For example, as shown in FIG. 15, a waveform shaper 312, a threshold x _th1, provided a large threshold x _th2 than the threshold x _th1, as in the following equation (12), when exceeding the threshold value x _th2 Can also output a logical value “2”. In this case, the number of output bits of the waveform shaper 312 is 2 bits or more.

  Next, the operation of the electronic device 1 will be described. FIG. 16 is a flowchart illustrating an example of the operation of the electronic device 1.

  In step S01, the control unit 90 activates the tone sound generation unit 50 to generate a tone sound having a predetermined frequency (for example, 20 kHz). The generated tone sound is radiated as a sound wave to the space via the amplifier 60 and the speaker 20.

  In step S02, the microphone 30 collects the sound wave emitted from the speaker 20. Sound waves collected by the microphone 30 are output to the digital signal processing unit 80 via the AD converter 70.

  In step S03, the digital signal processing unit 80 detects a change in sound pressure in the sound wave collected by the microphone 30. More specifically, the digital signal processing unit 80 detects a change in the sound pressure envelope.

  In step S04, the digital signal processing unit 80 determines whether or not an object (for example, a user's finger) has moved within a predetermined range based on the electronic device 1 based on a change in sound pressure.

  In step S05, the control unit 90 specifies a user operation based on the logical signal (0/1) output from the digital signal processing unit 80. Furthermore, the control unit 90 executes processing according to the specified operation.

  Examples of the electronic device 1 include a mobile phone, a smartphone, a game machine, a tablet PC (Personal Computer), a notebook PC, and a PDA (Personal Data Assistants).

  In the electronic device 1, the user's operation is specified using the speaker 20 and the microphone 30 fixed to the casing. When a sound wave having a predetermined frequency (for example, 20 kHz) is emitted from the speaker 20, the microphone 30 detects a steady sound wave (the sound pressure detected by the microphone 30 is not disturbed). However, under such circumstances, when a change in the space around the speaker 20 or the microphone 30 (such as the proximity of an object to the electronic device 1) occurs, the sound wave collected by the microphone 30 changes. In the electronic device 1, such a change in the sound pressure of the sound wave is used to detect movement of an operation unit (such as a finger or a stylus) for operating the electronic device 1. At that time, a change in sound pressure envelope (sound intensity envelope) is used without using the time required for reflection of the sound wave radiated from the speaker 20 or the difference in frequency associated with the reflection.

  As described above, the user interface for operating the electronic device 1 using the change in the envelope of the sound pressure is provided. Since the conversion of the sound pressure envelope is used, it is not necessary to display an icon or the like corresponding to the operation by the touch panel on the display device 10. Moreover, it is also possible to operate the electronic device 1 simultaneously with the operation using the touch panel. Furthermore, since the speaker 20 and the microphone 30 handle high frequencies, their mounting area does not increase (a small speaker or the like may be used). Therefore, it is possible to reduce the mounting area required for realizing the user interface.

  A part or all of the above embodiments can be described as in the following supplementary notes, but is not limited thereto.

[Appendix 1]
It is as the electronic device which concerns on the above-mentioned 1st viewpoint.
[Appendix 2]
The electronic device according to appendix 1, wherein the change detection unit detects a change in an envelope of the sound pressure.
[Appendix 3]
The change detection unit performs a Hilbert transform on a signal component generated from the sound wave detected by the sound wave detection unit, and calculates a standard norm of the signal component subjected to the Hilbert transform, thereby calculating the envelope. The electronic device of appendix 2 to be generated.
[Appendix 4]
The electronic device according to appendix 2 or 3, wherein the change detection unit applies a band-pass filter to the envelope.
[Appendix 5]
The change detector is a noise component extracted from the sound wave detected by the sound wave detector, and multiplies the noise component that vibrates around 0 by the amplitude of the envelope. The electronic device as described in any one.
[Appendix 6]
The electronic device according to any one of appendices 2 to 5, wherein the determination unit outputs a logic signal that defines the presence or absence of the movement of the object by comparing the amplitude of the envelope with a predetermined threshold value. machine.
[Appendix 7]
The electronic device according to any one of appendices 1 to 6, wherein the sound wave generation unit radiates sound waves having a frequency higher than an audible band to a space.
[Appendix 8]
The electronic device according to appendix 6 or 7, further comprising a control unit that identifies a user operation based on the logic signal and executes a process according to the identified operation.
[Appendix 9]
It is as the control method of the electronic device which concerns on the above-mentioned 2nd viewpoint.
[Appendix 10]
The electronic device control method according to appendix 9, wherein the step of detecting a change in sound pressure detects a change in an envelope of the sound pressure.
[Appendix 11]
The step of detecting the change in the sound pressure is performed by performing a Hilbert transform on a signal component generated from the sound wave detected by the sound wave detection unit and calculating a standard norm of the signal component after the Hilbert transform. The method of controlling an electronic device according to appendix 10, wherein the envelope is generated.
[Appendix 12]
The method of detecting an electronic device according to appendix 10 or 11, wherein the step of detecting a change in the sound pressure applies a band-pass filter to the envelope.
[Appendix 13]
The step of detecting a change in the sound pressure is a noise component extracted from the sound wave detected by the sound wave detection unit, and a noise component that vibrates around 0 and the amplitude of the envelope are multiplied. The method for controlling an electronic device according to any one of appendices 10 to 12.
[Appendix 14]
The step of determining whether or not the object has moved includes outputting a logic signal that specifies whether or not the object has moved by comparing the amplitude of the envelope with a predetermined threshold value. The control method of the electronic device as described in any one.
[Appendix 15]
The program is related to the third viewpoint.
[Appendix 16]
The program according to appendix 15, wherein the process of detecting a change in the sound pressure detects a change in an envelope of the sound pressure.
[Appendix 17]
The process of detecting the change in the sound pressure is performed by performing a Hilbert transform on the signal component generated from the sound wave detected by the sound wave detecting unit and calculating a standard norm of the signal component that has been subjected to the Hilbert transform. The program of appendix 16, which generates the envelope.
[Appendix 18]
The program according to appendix 16 or 17, wherein the process of detecting a change in the sound pressure applies a band-pass filter to the envelope.
[Appendix 19]
The process of detecting a change in sound pressure is a noise component extracted from the sound wave detected by the sound wave detection unit, and a noise component that vibrates around 0 and the amplitude of the envelope are multiplied. The program according to any one of supplementary notes 16 to 18.
[Appendix 20]
The process of determining whether or not the object has moved includes outputting a logic signal that specifies whether or not the object has moved by comparing the amplitude of the envelope with a predetermined threshold value. The program as described in any one.

  Each disclosure of the cited patent documents and the like cited above is incorporated herein by reference. Within the scope of the entire disclosure (including claims) of the present invention, the embodiments and examples can be changed and adjusted based on the basic technical concept. Various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) within the scope of the claims of the present invention, Selection is possible. That is, the present invention of course includes various variations and modifications that could be made by those skilled in the art according to the entire disclosure including the claims and the technical idea. In particular, with respect to the numerical ranges described in this document, any numerical value or small range included in the range should be construed as being specifically described even if there is no specific description.

DESCRIPTION OF SYMBOLS 1,100 Electronic device 10 Display device 20 Speaker 30 Microphone 40 Operation device 50 Tone sound generation part 60 Amplifier 70 AD converter 80 Digital signal processing part 90 Control part 101 Sound wave generation part 102 Sound wave detection part 103 Change detection part 104 Determination part 200 Home position 201, 202 One side 203, 204 of electronic device 1 Object 301, 304 Band pass filter 302 Hilbert transformer 303 Complex analysis signalization & standard norm calculator 305 Delay unit 306 Band stop filter 307 Standard norm calculator 308, 311 313 Low-pass filter 309 Noise detector 310 Multipliers 312, 314 Wave shape shaper

Claims (10)

A sound wave generator that radiates sound waves having a predetermined frequency to the space;
A sound wave detector for detecting the emitted sound wave;
A change detection unit for detecting a change in sound pressure of the sound wave detected by the sound wave detection unit;
A determination unit that determines the presence or absence of movement of an object within a predetermined range based on the change in the sound pressure;
An electronic device comprising:   The electronic device according to claim 1, wherein the change detection unit detects a change in an envelope of the sound pressure.   The change detection unit performs a Hilbert transform on a signal component generated from the sound wave detected by the sound wave detection unit, and calculates a standard norm of the signal component subjected to the Hilbert transform, thereby calculating the envelope. The electronic device according to claim 2 to be generated.   The electronic device according to claim 2, wherein the change detection unit applies a bandpass filter to the envelope.   5. The change detection unit multiplies a noise component that is extracted from a sound wave detected by the sound wave detection unit and vibrates around 0 by an amplitude of the envelope. 5. The electronic device as described in any one of.   The said determination part outputs the logic signal which prescribes | regulates the presence or absence of the movement of the said object by comparing the amplitude of the said envelope, and a predetermined threshold value. Electronic equipment.   The electronic device according to claim 1, wherein the sound wave generation unit radiates sound waves having a frequency higher than an audible band to a space.   8. The electronic apparatus according to claim 6, further comprising a control unit that specifies a user operation based on the logic signal and executes a process according to the specified operation. A sound wave generator that radiates sound waves having a predetermined frequency to the space;
A sound wave detector for detecting the emitted sound wave;
An electronic device control method comprising:
Detecting a change in sound pressure of sound waves detected by the sound wave detection unit;
Determining the presence or absence of movement of an object within a predetermined range based on the change in the sound pressure;
A method for controlling an electronic device, comprising: A sound wave generator that radiates sound waves having a predetermined frequency to the space;
A sound wave detector for detecting the emitted sound wave;
A program for causing a computer to control an electronic device comprising:
A process of detecting a change in sound pressure of a sound wave detected by the sound wave detection unit;
A process of determining the presence or absence of movement of an object within a predetermined range based on the change in the sound pressure;
A program that executes.

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