JP6234039B2 - Measuring apparatus and measuring method - Google Patents

Description

  The present invention relates to a measuring apparatus and a measuring method for evaluating an electronic device that transmits a sound based on vibration of a vibrating body to a user by pressing the vibrating body held in a housing against a human ear.

  Patent Document 1 describes an electronic device such as a mobile phone that transmits air conduction sound and bone conduction sound to a user (user). According to Patent Document 1, air conduction sound is sound transmitted to the auditory nerve of a user by vibration of air that is caused by vibration of an object being transmitted to the eardrum through the external auditory canal. Have been described. Patent Document 1 describes that bone conduction sound is sound transmitted to the user's auditory nerve through a part of the user's body (for example, cartilage of the outer ear) that contacts the vibrating object. ing.

  In the telephone set described in Patent Document 1, it is described that a short plate-like vibrating body made of a piezoelectric bimorph and a flexible material is attached to the outer surface of a housing via an elastic member. Further, in Patent Document 1, when a voltage is applied to the piezoelectric bimorph of the vibrating body, the vibrating body bends and vibrates as the piezoelectric material expands and contracts in the longitudinal direction, and the user contacts the vibrating body with the auricle. It is described that air conduction sound and bone conduction sound are transmitted to the user. In addition, unlike the telephone described in Patent Document 1, the present applicant flexibly vibrates a panel such as a display panel or a protective panel arranged on the surface of a mobile phone by a piezoelectric element, thereby generating air conduction. We are developing mobile phones that transmit sound using sound and vibration sound, which is a sound component of vibration transmission transmitted when a vibrating panel is applied to a human ear.

JP 2005-348193 A

  By the way, in order to bend and vibrate the panel with the piezoelectric element, it is assumed that the entire surface of the piezoelectric element is attached to the panel with an adhesive member such as a double-sided tape or an adhesive. At this time, it is also assumed that a buffer member is interposed between the piezoelectric element and the panel. As described above, when the piezoelectric element is attached to the panel, the vibration performance of the panel changes when the adhesion state of the piezoelectric element or the buffer member to the panel changes. For this reason, for example, when the piezoelectric element is continuously driven for a long period of time, it is assumed that the adhesion state of the piezoelectric element changes and the vibration performance that should be originally emitted does not appear. Such vibration performance cannot be evaluated without listening to the vibration sound transmitted when the ear is put on the panel, so it is difficult for humans to audition the vibration sound for hours and evaluate its subtle changes. .

  Therefore, an object of the present invention made in view of such a viewpoint is to provide a measuring apparatus and a measuring method capable of easily and accurately evaluating an electronic device that transmits a sound based on vibration of a vibrating body to a user.

In order to solve the above problems, a measurement apparatus according to the present invention is a measurement apparatus for evaluating an electronic device that presses a vibrating body held in a housing against a human ear and transmits sound to a user by vibration transmission. And
A test signal output unit for outputting a test signal for vibrating the vibrating body;
A vibration detector for detecting vibration of the vibrating body;
A measurement unit that analyzes the vibration of the vibrating body based on the output of the vibration detection unit,
The measurement unit repeatedly outputs the test signal from the test signal output unit a specified number of times over a predetermined frequency range to vibrate the vibrating body, and outputs the vibration detection unit in the sequential repetition of the test signal. Based on this, the variation of the frequency characteristic of the vibration is analyzed.

  According to the present invention, there is provided a measuring apparatus and a measuring method capable of easily and accurately evaluating an electronic device that transmits a sound based on vibration of a vibrating body to a user by pressing the vibrating body held in the housing against a human ear. Can be provided.

It is a figure which shows schematic structure of the measuring apparatus which concerns on one embodiment. It is a top view which shows an example of the electronic device of a measuring object. It is a figure which shows the structure of the vibration pick-up apparatus of FIG. FIG. 2 is a partial detail view of the vibration measuring head of FIG. 1. It is a functional block diagram of the principal part of the measurement part of FIG. It is a figure which shows an example of the setting screen of the aging test by the measurement part of FIG. It is a figure which shows the example of a display of the frequency characteristic by an aging test. It is a figure which shows the example of a display of the output fluctuation | variation in the monitoring frequency by an aging test. It is a figure which shows an example of the setting screen of the problem reproduction test by the measurement part of FIG. It is a figure for demonstrating the time difference of the output timing of a test sound in a problem reproduction test, and a reproduction start timing.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of a measurement apparatus according to an embodiment. A measuring apparatus 10 according to the present embodiment is for evaluating an electronic device 100 to be measured having a vibrating body, and is connected to the electronic device mounting unit 20 and the electronic device mounting unit 20 and the electronic device 100. A measurement unit 200. The electronic device mounting unit 20 includes a vibration measurement head 40 supported by the base 30 and a holding unit 70 that holds the electronic device 100 to be measured. In the following description, the electronic device 100 is a mobile phone such as a smartphone having a rectangular panel 102 larger than a human ear on the surface of a rectangular casing 101 as shown in a plan view in FIG. A piezoelectric element is attached to the back surface of the panel 102, and the panel 102 vibrates as a vibrating body by driving the piezoelectric element. First, the vibration measuring head 40 will be described.

  The vibration measuring head 40 includes an ear mold portion 50 and a vibration pickup device 55. The ear mold part 50 imitates the human ear and includes an ear model 51 and an artificial external ear canal part 52 coupled to the ear model 51. 1 corresponds to the right ear of a person, but may be the left ear. An artificial external ear canal 53 is formed in the central portion of the artificial external ear canal portion 52. The artificial external ear canal 53 is formed with a hole diameter of 5 mm to 10 mm, which is an average diameter of a human external ear canal. The ear mold part 50 is detachably supported by the base 30 via a support member 54 at the peripheral part of the artificial external ear canal part 52. Alternatively, the artificial external ear canal portion 52 may be bonded to the ear mold portion 50. Alternatively, the ear mold portion 50 and the external ear canal portion 52 may be integrally manufactured using a single mold.

  The ear mold part 50 is made of, for example, a material similar to the material of an average ear model used for, for example, HATS (Head And Torso Simulator) of a human body model or KEMAR (a name of an electronic mannequin for acoustic research of Knowles). It consists of the material based on IEC60318-7. This material can be formed of a material such as rubber having a hardness of 35 to 55, for example. The rubber hardness may be measured in accordance with, for example, international rubber hardness (IRHD / M method) compliant with JIS K 6253 or ISO 48. Moreover, as a hardness measuring apparatus, the fully automatic type IRHD * M method micro size international rubber hardness tester GS680 by Teclock Co., Ltd. is used suitably. In consideration of the variation in the hardness of the ear depending on the age, the ear mold portion 50 may be prepared by roughly preparing two to three types of different hardness, and replacing them.

  The thickness of the artificial external auditory canal 52, that is, the length of the artificial external auditory canal 53 corresponds to the length to the human eardrum (cochlea), and is appropriately set within a range of, for example, 5 mm to 50 mm, preferably 8 mm to 30 mm. . In the present embodiment, the length of the artificial external ear canal 53 is approximately 30 mm.

  The vibration pickup device 55 has a hole 56a having substantially the same diameter as that of the artificial external ear canal 53, for example, a diameter of 7.5 mm, as shown in a plan view in FIG. 3A and a front view in FIG. A plate-like vibration transmission member 56 and one vibration pickup 57 constituting a vibration detection unit coupled to a part of one surface of the vibration transmission member 56 are provided. In the present embodiment, the other surface of the vibration transmitting member 56 is bonded to the end surface of the artificial external auditory canal portion 52 opposite to the ear model 51 side so that the hole 56a communicates with the artificial external auditory canal 53. In addition, the vibration pickup 57 is coupled to one surface of the vibration transmission member 56 via, for example, an adhesive or grease. The vibration pickup 57 is connected to the measurement unit 200.

  Here, the vibration transmission member 56 can be made of a material having good vibration transmission efficiency, for example, metal, alloy such as iron, SUS, brass, aluminum, titanium, or plastic, but is light in terms of detection sensitivity. Preferably, it is made of a material. Further, the vibration transmitting member 56 may have a rectangular outer shape such as a square flat washer. However, since the displacement amount of the ear mold portion 50 is large in the peripheral portion of the artificial external ear canal 53, a round shape is used in the present embodiment. It has a ring shape like a flat washer. The ring-shaped outer shape can be formed, for example, as an outer diameter obtained by doubling the ring width from 6 mm to 20 mm to about 10 mm to 30 mm in diameter of the hole 56a. Further, the thickness of the vibration transmitting member 56 is appropriately set according to the strength of the material. As the above-described vibration transmission member 56, for example, a SUS plate having a thickness of 0.1 mm may be used to have an inner diameter of 25 mm and a width of 5 mm, that is, an outer diameter of 35 mm.

  As the vibration pickup 57, a known small vibration pickup can be used. In the present embodiment, a piezoelectric acceleration pickup is used as the vibration pickup 57, and the piezoelectric acceleration pickup is attached to the vibration transmission member 56 via a bonding member such as grease or an instantaneous adhesive such as Aron Alpha (registered trademark). Are connected.

  Furthermore, the vibration measuring head 40 includes a microphone device 60 for measuring the sound pressure of the sound propagated through the artificial external ear canal 53. As shown in FIG. 4A, the microphone device 60 is a plan view seen from the base 30 side, and FIG. 4B is a cross-sectional view taken along the line bb of FIG. A tube member 61 extending from an outer wall (peripheral wall of the hole) through a hole 56a of the vibration transmission member 56 of the vibration pickup device 55, and a microphone 62 constituting a sound pressure measurement unit held by the tube member 61 are provided.

  The microphone 62 includes, for example, a measurement capacitor microphone having a flat output characteristic in the measurement frequency range of the electronic device 100 and a low self-noise level. The microphone 62 is arranged such that the sound pressure detection surface substantially coincides with the end surface of the artificial external ear canal unit 52. The microphone 62 may be arranged in a state of being fixed to the outer wall of the artificial external ear canal 53, for example. Alternatively, it may be supported by the artificial ear canal unit 52 or the base 30 and arranged in a floating state from the outer wall of the artificial ear canal 53. The microphone 62 is connected to the measurement unit 200. In FIG. 4A, the artificial external auditory canal portion 52 has a rectangular shape, but the artificial external auditory canal portion 52 can have an arbitrary shape.

  Next, the holding unit 70 will be described. In the case where the electronic device 100 is a mobile phone having a rectangular shape in a plan view such as a smartphone, when a person tries to hold the mobile phone with one hand and press it against his / her ear, the both sides of the mobile phone are usually held by hands. Will be supported by. Further, the pressing force and contact posture of the mobile phone against the ear vary depending on the person (user) or fluctuates during use. In the present embodiment, electronic device 100 is held by imitating such a usage mode of a mobile phone.

  Therefore, the holding part 70 includes support parts 71 that support both side parts of the electronic device 100. The support portion 71 is attached to one end portion of the arm portion 72 so as to be rotatable and adjustable around an axis y1 parallel to the y axis in a direction in which the electronic device 100 is pressed against the ear mold portion 50. The other end of the arm portion 72 is coupled to a movement adjusting portion 73 provided on the base 30. The movement adjusting unit 73 moves the arm unit 72 in the direction parallel to the x axis orthogonal to the y axis, the vertical direction x1 of the electronic device 100 supported by the support unit 71, and the z axis orthogonal to the y axis and the x axis. In a direction parallel to the direction z1 in which the electronic device 100 is pressed against the ear mold portion 50.

  As a result, the electronic device 100 supported by the support portion 71 adjusts the support portion 71 about the axis y1 or adjusts the movement of the arm portion 72 in the z1 direction. 102) is pressed against the ear mold 50. In the present embodiment, the pressing force is adjusted in the range of 0N to 10N, preferably in the range of 3N to 8N.

  Here, the range of 0N to 10N is for the purpose of enabling measurement in a sufficiently wide range than the pressing force assumed when a person presses an electronic device against his / her ear to use a telephone call or the like. Yes. In the case of 0N, for example, not only when the ear mold part 50 is in contact but not pressed, it can be held away from the ear mold part 50 in 1 mm to 1 cm increments, and measurement can be performed at each separation distance. You may be able to do it. Thereby, the degree of attenuation due to the distance of the airway sound can be measured by the microphone 62, and the convenience as a measuring apparatus is improved. In addition, the range of 3N to 8N usually assumes an average force range that a normal hearing person presses against an ear when making a call using a conventional speaker. Although there may be differences depending on race and gender, in general, in electronic devices such as smartphones and conventional mobile phones equipped with conventional speakers, vibration and airway sounds are usually generated with a pressing force that is pressed by the user. It is preferable that it can be measured.

  In addition, by adjusting the movement of the arm unit 72 in the x1 direction, the contact posture of the electronic device 100 with respect to the ear mold unit 50 is, for example, the posture in which the panel 102 which is an example of a vibrating body covers almost the entire ear mold unit 50 As shown in FIG. 1, the panel 102 is adjusted so as to cover a part of the ear mold portion 50. The arm portion 72 is configured to be movable and adjustable in a direction parallel to the y-axis, or is configured to be rotatable and adjustable around an axis parallel to the x-axis and the z-axis, so that the ear-shaped portion 50 can be adjusted. Thus, the electronic device 100 may be configured to be adjustable to various contact postures. Needless to say, the vibrating body is not limited to a panel that covers a wide range of ears, but an electronic device having protrusions and corners that transmit vibration only to a part of the ear mold 50, for example, the part of the tragus. Even a device can be a measurement object of the present invention.

  Next, the configuration of the measurement unit 200 in FIG. 1 will be described with reference to FIG. FIG. 5 is a functional block diagram of a main part of the measuring apparatus of FIG. The measurement unit 200 includes a sensitivity adjustment unit 300, a signal processing unit 400, a PC (personal computer) 500, and a printer 600.

  Outputs of the vibration pickup 57 and the microphone 62 are supplied to the sensitivity adjustment unit 300. The sensitivity adjustment unit 300 includes a variable gain amplification circuit 301 that adjusts the amplitude of the output of the vibration pickup 57 and a variable gain amplification circuit 302 that adjusts the amplitude of the output of the microphone 62. The variable gain amplifier circuits 301 and 302 independently adjust the amplitude of the analog input signal corresponding to each circuit to a required amplitude manually or automatically. Thereby, the error of the sensitivity of the vibration pickup 57 and the sensitivity of the microphone 62 is corrected. Note that the variable gain amplifier circuits 301 and 302 are configured so that the amplitude of the input signal can be adjusted within a range of ± 50 dB, for example.

  The output of the sensitivity adjustment unit 300 is supplied to the signal processing unit 400. The signal processing unit 400 includes an A / D conversion unit 410, a frequency characteristic adjustment unit 420, a phase adjustment unit 430, an output synthesis unit 440, a frequency analysis unit 450, a storage unit 460, an acoustic signal output unit 480, and a signal processing control unit 470. Prepare. The A / D conversion unit 410 converts an output of the variable gain amplification circuit 301 into a digital signal, an A / D conversion circuit (A / D) 411, and an A / D that converts the output of the variable gain amplification circuit 302 into a digital signal. A conversion circuit (A / D) 412. The A / D conversion circuits 411 and 412 can handle, for example, 16 bits or more and 96 dB or more in terms of dynamic range. Further, the A / D conversion circuits 411 and 412 can be configured so that the dynamic range can be changed.

  The output of the A / D conversion unit 410 is supplied to the frequency characteristic adjustment unit 420. The frequency characteristic adjustment unit 420 detects an equalizer (EQ) 421 that adjusts a frequency characteristic of a detection signal by the vibration pickup 57 that is an output of the A / D conversion circuit 411 and a microphone 62 that is an output of the A / D conversion circuit 412. And an equalizer (EQ) 422 for adjusting the frequency characteristics of the signal. The equalizers 421 and 422 independently adjust the frequency characteristics of the respective input signals manually or automatically to frequency characteristics close to human hearing. Note that the equalizers 421 and 422 are composed of, for example, a multiband graphical equalizer, a low-pass filter, a high-pass filter, and the like.

  The output of the frequency characteristic adjustment unit 420 is supplied to the phase adjustment unit 430. The phase adjustment unit 430 includes a variable delay circuit 431 that adjusts the phase of a detection signal by the vibration pickup 57 that is an output of the equalizer 421. That is, the speed of sound transmitted through the material of the ear mold 50 and the speed of sound transmitted through the flesh and bones of the human body are not exactly the same. It is assumed that the deviation from the ear becomes large.

  In this way, when the phase relationship between the output of the vibration pickup 57 and the output of the microphone 62 deviates greatly, an amplitude peak or dip appears at a timing different from the actual time when both outputs are combined by the output combining unit 440 described later. Or the composite output may increase or decrease. Therefore, in the present embodiment, the phase of the detection signal by the vibration pickup 57 that is the output of the equalizer 421 can be adjusted within a predetermined range by the variable delay circuit 431 according to the measurement frequency range of the electronic device 100 to be measured. .

  For example, when the measurement frequency range of the electronic device 100 is 100 Hz to 10 kHz, a unit smaller than at least 0.1 ms (equivalent to 10 kHz) in a range of about ± 10 ms (equivalent to ± 100 Hz) by the variable delay circuit 431, for example, 0.04 μs unit Thus, the phase of the detection signal from the vibration pickup 57 is adjusted. Even in the case of a human ear, a phase shift occurs between the bone conduction sound (vibration transmission component) and the air conduction sound (air conduction component). Therefore, the phase adjustment by the variable delay circuit 431 is performed by the vibration pickup 57 and the microphone 62. It does not mean that the phases of both detection signals are matched, but means that the phases of both are matched to the actual audibility of the ear.

  The output of the phase adjustment unit 430 is supplied to the output synthesis unit 440. The output combining unit 440 combines the detection signal from the vibration pickup 57 whose phase has been adjusted by the variable delay circuit 431 and the detection signal from the microphone 62 that has passed through the phase adjustment unit 430. As a result, it is possible to obtain the vibration amount and sound pressure transmitted by the vibration of the electronic device 100 to be measured, that is, the sensory sound pressure obtained by synthesizing the vibration transmission component and the air conduction component by approximating the human body.

  The synthesized output of the output synthesis unit 440 is supplied to the frequency analysis unit 450. The frequency analysis unit 450 includes an FFT (Fast Fourier Transform) 451 that performs frequency analysis on the synthesized output from the output synthesis unit 440. Thereby, power spectrum data corresponding to the body sensation sound pressure in which the vibration transmission component and the air conduction component are synthesized is obtained from the FFT 451.

  Further, the frequency analysis unit 450 includes FFTs 452 and 453 for performing frequency analysis on the signal before being synthesized by the output synthesis unit 440, that is, the detection signal by the vibration pickup 57 that has passed through the phase adjustment unit 430 and the detection signal by the microphone 62, respectively. Prepare. Thereby, power spectrum data corresponding to the vibration transfer component is obtained from the FFT 452, and power spectrum data corresponding to the air conduction component is obtained from the FFT 453.

  Note that FFT 451 to 453 are set with analysis points of frequency components (power spectrum) according to the measurement frequency range of electronic device 100. For example, when the measurement frequency range of the electronic device 100 is 100 Hz to 10 kHz, the frequency component at each point obtained by equally dividing the interval in the logarithmic graph of the measurement frequency range by 100 to 2000 is set.

  Outputs of the FFTs 451 to 453 are stored in the storage unit 460. The storage unit 460 has a capacity larger than a double buffer capable of holding a plurality of pieces of analysis data (power spectrum data) obtained by the FFTs 451 to 453. The storage unit 460 can be configured to always transmit the latest data at a data transmission request timing from the PC 500 described later. It should be noted that the double buffer configuration is not necessarily required unless analysis is required in real time.

  The acoustic signal output unit 480 is configured so that an external connection device such as headphones can be detachably connected. The acoustic signal output unit 480 includes any of a detection signal from the vibration pickup 57 input to the output synthesis unit 440 by the signal processing control unit 470, a detection signal from the microphone 62, or a synthesis signal from the output synthesis unit 440. Is selected and supplied. The acoustic signal output unit 480 appropriately adjusts the frequency characteristics of input data with an equalizer or the like, and then performs D / A conversion to an analog acoustic signal for output.

  Further, the signal processing unit 400 includes a test signal output unit 495. The test signal output unit 495 outputs a test signal for evaluating the electronic device 100 by vibrating the panel 102 of the electronic device 100 under the control of the signal processing control unit 470. The test signal output unit 495 includes a test signal generation unit 496, a test signal storage unit 497, and an output adjustment unit 498. The test signal generator 495 is preferably a desired single frequency sine wave signal (pure tone), a pure tone sweep in which the frequency sequentially changes from a low frequency to a high frequency or from a high frequency to a low frequency over a predetermined frequency range. A multisine wave signal (multisine) composed of a plurality of sine wave signals having different signals (pure tone sweep) and frequencies is selectively generated and output. The predetermined frequency range in the pure tone sweep can be set as appropriate within the audible frequency range. The amplitudes at sequential frequencies in the pure tone sweep are preferably the same. Also for multisine, the amplitude of each sine wave is preferably the same.

  The test signal storage unit 497 stores at least a required WAV file (audio data) and is configured to be selectively readable. The WAV file stored in the test signal storage unit 497 is downloaded and stored via a recording medium or a network, for example. The output adjustment unit 498 converts the test signal output from the test signal generation unit 496 or the test signal storage unit 497 into, for example, an analog signal according to the signal format of the external input of the electronic device 100 to be measured. And is supplied to the external input terminal 105 of the electronic device 100 via a connection cable 511 for an interface such as a USB. Note that the test signal output from the test signal output unit 495 may be a signal that complies with a standard such as 3GPP2 (3GPP TS26.131 / 132) or VoLTE when the electronic device 100 is a mobile phone.

  The signal processing control unit 470 is connected to the PC 500 via an interface connection cable 510 such as a USB, RS-232C, SCSI, or PC card. The signal processing control unit 470 controls the operation of each unit of the signal processing unit 400 based on a command from the PC 500. The sensitivity adjustment unit 300 and the signal processing unit 400 may be configured as software executed on any suitable processor such as a CPU (central processing unit) or may be configured by a DSP (digital signal processor). it can.

  The PC 500 includes a memory 501 for storing an evaluation application of the electronic device 100 by the measuring apparatus 10 and various data. The memory 501 may be a built-in memory or an external memory. The evaluation application is downloaded to the memory 501 via, for example, a CD-ROM or a network. For example, the PC 500 displays an application screen based on the evaluation application on the display unit 520. Further, a command is transmitted to the signal processing unit 400 based on information input via the application screen. The PC 500 receives a command response and data from the signal processing unit 400, performs predetermined processing based on the received data, and displays the measurement result on the application screen. Further, if necessary, the measurement result is output to the printer 600 and printed.

  The measuring apparatus 10 has an aging test function and a problem reproduction function as an evaluation application of the electronic device 100. The aging test function presents a pure tone sweep test signal, repeats the process of measuring the response a specified number of times in succession, and analyzes the variation in the frequency characteristics measured during that time.

  The problem reproduction function presents a specific test signal, measures its response, and creates a problem based on a comparison between the cross-correlation coefficient between the test signal (presentation sound) and the measured sound and the set cross-correlation coefficient threshold. Measurement data that reproduces the above phenomenon is stored in the memory 501 of the PC 500. That is, the similarity between the two signals of the presentation sound and the measurement sound is confirmed by the cross-correlation function, and the measurement data that falls below the set correlation coefficient threshold is stored in the memory 501 of the PC 500 as data that reproduces the problem phenomenon. .

  Hereinafter, the aging test function and the problem reproduction function will be described in more detail.

<Aging test function>
In the aging test, fluctuations in the entire frequency characteristic and fluctuations at a specified specific frequency are measured. FIG. 6 is a diagram illustrating an example of an aging test setting screen displayed on the display unit 520 in the aging test. The aging test setting screen 700 is activated from the evaluation application menu of the measuring apparatus 10. The aging test setting screen 700 includes a test sound amplitude setting unit 701, a repeat count setting unit 702, a monitoring frequency setting unit 703, a test start icon 704, and a test stop icon 705. A pure tone sweep is set for the test sound (test signal).

  A desired amplitude (dB) of the test sound is input to the test sound amplitude setting unit 701. The repeat count setting unit 702 receives a desired repeat count that is equal to or less than the maximum repeat count (for example, 10,000) of the pure tone sweep. The monitoring frequency setting unit 703 is prepared for measuring the sound pressure fluctuation in units of frequency. For example, an arbitrary frequency between 100 Hz and 10 KHz is input to the monitoring frequency input unit 703. In FIG. 6, three monitoring frequencies can be input.

  The measuring apparatus 10 starts the aging test when the input to the test sound amplitude setting unit 701, the repeat count setting unit 702, and the monitoring frequency setting unit 703 is completed and the test start icon 704 is operated. Hereinafter, an operation example of the aging test by the measuring apparatus 10 will be described.

  First, when the test start icon 704 on the aging test setting screen 700 in FIG. 6 is operated, the PC 500 transmits an aging test measurement start command to the signal processing unit 400. When the signal processing unit 400 receives the measurement start command for the aging test, the test signal generation unit 496 of the test signal output unit 495 repeatedly generates a pure tone sweep under the control of the signal processing control unit 470. The generated pure tone sweep is supplied to the external input terminal 105 of the electronic device 100 to be measured held by the holding unit 70 via the output adjustment unit 498 and the connection cable 511. Thereby, the piezoelectric element affixed to the back surface of the panel 102 of the electronic device 100 is driven, the panel 102 vibrates, and the aging test of the electronic device 100 is started.

  When the aging test starts, the signal processing unit 400 adjusts the sensitivity of the outputs of the vibration pickup 57 and the microphone 62 by the sensitivity adjustment unit 300, converts the output to a digital signal by the A / D conversion unit 410, and further adjusts the frequency characteristics. After the frequency characteristic is adjusted by the unit 420, the phase is adjusted by the phase adjustment unit 430 and synthesized by the output synthesis unit 440. Thereafter, the signal processing unit 400 frequency-analyzes the combined signal from the output combining unit 440, that is, the combined signal of the vibration transfer component and the air conduction component, by the FFT 451 of the frequency analysis unit 450, and the result is stored in the memory 501 of the PC 500. save.

  The measurement unit 200 executes the above-described processing for one pure tone sweep, and repeats the processing until the set number of repeats of the pure tone sweep expires or the test stop icon 705 is operated. When the set number of repeats expires or the test stop is operated, the PC 500 determines the frequency characteristic at the first measurement and the fluctuation of the overall sound pressure that indicates the total value of the sound pressure level at each frequency. A comparison graph with the frequency characteristics is displayed on the display unit 520. It should be noted that the absolute value of the difference between the first sound pressure level at each frequency and the sound pressure level at the time of the Nth measurement (N is one of the number of times measured from 1) is summed, and N times The graph showing the comparison between the time when the overall value is the largest and the first time may be displayed on the display unit 520 as the time when the overall sound pressure fluctuation is the largest when the summed value is the largest.

  FIG. 7 shows an example of a comparison graph of frequency characteristics displayed on the display unit 520. In FIG. 7, the horizontal axis represents frequency (Hz), the vertical axis represents sound pressure (dBSPL), the broken line in the graph represents the initial frequency characteristic, and the solid line represents the frequency characteristic at the time when the fluctuation of the overall sound pressure value was the largest. Respectively.

  Further, the measurement unit 200 selectively displays an output fluctuation graph at the set monitoring frequency on the display unit 520 in accordance with an input operation by the tester. FIG. 8 shows an example of an output fluctuation graph at the monitoring frequency displayed on the display unit 520. In FIG. 8, the horizontal axis indicates the number of repeats, and the vertical axis indicates the sound pressure (dBSPL). The measurement result at each monitoring frequency is the measurement result at the frequency closest to the set frequency among the sequential frequencies in the pure tone sweep. The result of the aging test of the electronic device 100 is output from the printer 600 as necessary.

  Through the above aging test, it is possible to evaluate a subtle change in sound when the piezoelectric element attached to the panel 102 of the electronic device 100 is continuously driven to apply a load to the bonded state.

<Problem reproduction function>
In the problem reproduction test, the cross-correlation function is used to check the similarity of the two signals of the presentation sound (test sound) and the measurement sound, and clip sound, temporary sound interruption, sound interruption due to wireless communication, unintentional sound The presence or absence of problems such as encoding / decoding conversion is detected. FIG. 9 is a diagram illustrating an example of a problem reproduction setting screen displayed on the display unit 520 in the problem reproduction test. Similar to the above-described aging test setting screen 700, the problem reproduction setting screen 800 is activated from the evaluation application menu of the measuring apparatus 10.

  The problem reproduction setting screen 800 includes a test sound type setting unit 801, a frequency setting unit 802, a test sound amplitude setting unit 803, a test sound time length setting unit 804, a repeat count setting unit 805, a correlation coefficient threshold setting unit 806, and a test start. An icon 807 and a test stop icon 808 are provided. The test sound type setting unit 801 selects and sets the test sound to be presented from pure sound / pure sound sweep / multisign / arbitrary WAV file. Since the WAV file is read from the test signal storage unit 497 of the test signal output unit 495 and output, the test sound type setting unit 801 also has a path name indicating the save destination of the WAV file in the test signal storage unit 497. Is displayed.

  When a pure tone is set in the test sound type setting unit 801, the frequency is input to the frequency setting unit 802. The test sound amplitude setting unit 803 receives a desired amplitude (dB) of the test sound. The test sound duration setting unit 804 receives the reproduction time of the test sound to be presented. Since the problem reproduction test calculates the cross-correlation between the test sound and the measurement sound, a long measurement time is not suitable. Therefore, even in the case of a WAV file, the time is preferably up to 10 seconds. The repeat count setting unit 805 receives a desired repeat count that is repeated until the problem is reproduced at a maximum repeat count (for example, 10,000 times) or less.

  The correlation coefficient threshold value setting unit 806 receives a correlation coefficient threshold value between the test sound and the measurement sound. Since the normal range changes depending on the presence / absence of wireless communication of the electronic device 100, the specification of acoustic processing, and the like, the correlation coefficient can be arbitrarily set within a range of 0.0 to 1.0, for example. The correlation coefficient is, for example, 0.7 to 1.0 when there is a strong correlation, 0.4 to 0.7 when there is a moderate correlation, and 0.0 to 0.4 when there is almost no correlation. It is arbitrarily set within the range.

  The measurement apparatus 10 completes input to the test sound type setting unit 801, the frequency setting unit 802, the test sound amplitude setting unit 803, the test sound time length setting unit 804, the repeat count setting unit 805, and the correlation coefficient threshold setting unit 806. Then, when the test start icon 807 is operated, measurement of problem reproduction is started. Hereinafter, an operation example of the problem reproduction function by the measurement apparatus 10 will be described.

  First, when the test start icon 807 on the problem reproduction setting screen 800 in FIG. 9 is operated, the PC 500 transmits a problem reproduction test start command to the signal processing unit 400. When receiving the problem reproduction test start command, the signal processing unit 400 outputs the test sound (test signal) set from the test signal output unit 495 under the control of the signal processing control unit 470. For example, when the WAV file is set in the test sound type setting unit 801, the signal processing unit 400 reads the WAV file set from the test signal storage unit 497 and outputs it through the output adjustment unit 498. When pure tone, pure tone sweep, or multisign is set, the signal processing unit 400 generates the test sound set from the test signal generation unit 496 and outputs it through the output adjustment unit 498. The test sound output from the test signal output unit 495 is also supplied to the PC 500 via the signal processing control unit 470.

  When the loopback is used, the test sound output from the measurement unit 200 is input to the external input terminal 105 of the electronic device 100 to be measured via the connection cable 511 as illustrated in FIG. On the other hand, in the case of wireless communication, it is input via the connection cable 511 to the external input terminal of the opposite device that communicates with the electronic device 100 to be measured. Therefore, there is a difference in the time until the presented test sound is played back by the electronic device 100 to be measured depending on the presence or absence of wireless communication.

  The signal processing unit 400 combines the outputs of the vibration pickup 57 and the microphone 62 by the output combining unit 440 in the same manner as in the aging test. Thereafter, the signal processing unit 400 performs frequency analysis on the combined signal from the output combining unit 440, that is, the combined signal of the vibration transfer component and the air conduction component, by the FFT 451 of the frequency analysis unit 450, and supplies the result to the PC 500. The PC 500 is presented as a combined waveform of the vibration transfer component and the air conduction component based on the frequency analysis result of the measurement sound from the signal processing unit 400 and the frequency analysis result of the presentation sound (test sound) processed in the PC 500. A correlation coefficient is obtained by calculating a cross correlation function with the waveform of the test sound, and the calculated correlation coefficient is compared with a set correlation coefficient threshold value.

  Here, as shown in FIGS. 10A and 10B, the output timing of the test sound from the measurement unit 200 (FIG. 10A) and the test sound reproduction start timing by the electronic device 100 to be measured ( In FIG. 10B, there is a time difference τ. Moreover, the time difference τ varies depending on conditions such as loopback and wireless communication. Therefore, the PC 500 calculates a correlation coefficient between the test sound and the measurement sound from the time when the measurement sound having a level exceeding the noise level is input. Note that a predetermined pilot signal may be inserted at the head of the measurement sound, and the PC 500 may start calculating the correlation coefficient in synchronization with the detection of the pilot signal. In addition, in the case of a WAV file, for example, in the case of a WAV file, the analysis length for obtaining a correlation coefficient in the PC 500 is not limited to all 10 seconds, but is divided into short times (for example, 0.5 seconds). It is desirable to calculate the correlation coefficient and compare it with the threshold value. When the test sound is a pure tone sweep, it is preferable to calculate the correlation over the entire sweep waveform.

  If the calculated correlation coefficient is equal to or greater than the set correlation coefficient threshold value, the PC 500 calculates that there is no problem and calculates the correlation coefficient from the presentation of the test sound and compares it with the threshold value until the set number of repeats is completed. Repeat the series of processing until If the calculated correlation function falls below the threshold before the repeat count is completed, the PC 500 displays a “problem reproduction” message on the display unit 520 and displays the waveform data (frequency analysis result) at that time. ) Is stored in the memory 501 of the PC 500. The waveform data stored in the memory 501 is output from the printer 600 as necessary. When no problem occurs, that is, when the calculated correlation coefficient is greater than or equal to the threshold value, the waveform data is not saved.

  By using the above problem reproduction function, various test sounds are presented and the correlation between the presentation sound and the measurement sound is calculated, so that it is possible to detect not only the clip sound of the electronic device 100 but also a temporary sound interruption. become. Furthermore, by presenting the test sound from the opposite device to the electronic device 100 by wireless communication, it becomes possible to detect the occurrence of problems such as sound interruption due to wireless communication and unintended sound encoding / decoding conversion, It is possible to detect various problems related to sound.

  In addition, this invention is not limited only to the said embodiment, Many deformation | transformation or a change is possible. For example, in the above-described embodiment, it is assumed that the electronic device 100 to be measured is a mobile phone such as a smartphone and the panel 102 vibrates as a vibrating body. An electronic device in which a panel in contact with the ear vibrates can be similarly evaluated. In addition to mobile phones, other piezoelectric receivers and hearing aids such as headsets and speakers using BlueTooth (registered trademark) that transmit sound by vibration transmission can be similarly evaluated. Further, the test signal output unit 495 may be incorporated in the PC 500 so as to supply a test signal from the PC 500 to the electronic device 100 to be measured or a counter device of the electronic device 100.

  In addition, the vibration measuring head 40 of the electronic device mounting unit 20 and the holding unit 70 that holds the electronic device 100 are not limited to the above-described configurations, and the electronic device 100 is detachably held so that at least the vibration component of the vibrating body is measured. Any configuration can be used. Further, depending on the characteristics measured by the vibrating body, such as measuring the direct vibration of the vibrating body, the ear mold 50 and the microphone device 60 may be omitted. Further, depending on the configuration of the vibration measuring head 40, the FFTs 452 and 453 are omitted, or the FFTs 451 and 453 are omitted, and an aging test and a problem reproduction test are performed based on the frequency characteristics of the vibration transfer component by the FFT 452. It may be.

  In the above embodiment, the measurement unit 200 is provided with the PC 500 separately from the signal processing unit 400. However, the function of the evaluation application executed by the PC 500 is mounted on the signal processing unit 400, and the PC 500 is omitted. May be. Furthermore, the measurement unit 200 is not limited to a configuration that is independent and aggregates all functions, but has a configuration that utilizes a network system or cloud, such as a case where the measurement unit 200 is divided into one or a plurality of PCs or external servers. Needless to say, it may be.

DESCRIPTION OF SYMBOLS 10 Measurement apparatus 30 Base 40 Vibration measurement head 50 Ear-shaped part 55 Vibration pick-up apparatus 57 Vibration pick-up 60 Microphone apparatus 62 Microphone 70 Holding part 100 Electronic device 101 Case 102 Panel (vibration body)
200 Measurement Unit 300 Sensitivity Adjustment Unit 400 Signal Processing Unit 410 A / D Conversion Unit 420 Frequency Characteristic Adjustment Unit 430 Phase Adjustment Unit 440 Output Synthesis Unit 450 Frequency Analysis Unit 460 Storage Unit 470 Signal Processing Control Unit 480 Acoustic Signal Output Unit 500 PC ( Personal computer)
501 Memory 600 Printer

Claims (7)

A measuring device for evaluating an electronic device that presses a vibrating body held in a housing against a human ear and transmits sound to a user by vibration transmission,
A test signal output unit for outputting a test signal for vibrating the vibrating body;
A vibration detector for detecting vibration of the vibrating body;
A measurement unit that analyzes the vibration of the vibrating body based on the output of the vibration detection unit,
The measurement unit repeatedly outputs the test signal from the test signal output unit a specified number of times over a predetermined frequency range to vibrate the vibrating body, and outputs the vibration detection unit in the sequential repetition of the test signal. A measuring device for analyzing a variation in frequency characteristics of the vibration based on the measurement result. A sound pressure measuring unit for measuring the sound pressure of the sound generated from the electronic device when the vibrating body is vibrated;
The measurement unit analyzes fluctuations in frequency characteristics of vibration based on a combined output of the output of the sound pressure measurement unit and the output of the vibration detection unit.
The measuring apparatus according to claim 1. A display unit;
The measurement unit displays the first frequency characteristic according to the test signal of the vibrator and the frequency characteristic of the time when the fluctuation of the overall sound pressure is the largest for the first frequency characteristic on the display unit.
The measuring apparatus according to claim 1 or 2. The measurement unit selectively displays the sound pressure of the frequency component corresponding to the designated monitoring frequency in the predetermined frequency range on the display unit over the designated number of times.
The measuring apparatus according to claim 3. The test signal output from the test signal output unit is a pure tone sweep signal in which the frequency sequentially changes over a predetermined frequency range.
The measuring apparatus according to claim 1. When evaluating an electronic device that presses the vibrating body held in the housing against the human ear and transmits the sound to the user by vibration transmission,
A step of repeatedly outputting a test signal a specified number of times over a predetermined frequency range from a test signal output unit to vibrate the vibrating body;
Detecting vibration of the vibrating body in a sequential repetition of the test signal by a vibration detector;
Analyzing a variation in frequency characteristics of the vibration in the measurement unit based on the output of the vibration detection unit;
Measuring method including The test signal output from the test signal output unit is a pure tone sweep signal in which the frequency sequentially changes over a predetermined frequency range.
The measurement method according to claim 6 .

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