JP2012029102A - Acoustic system and acoustic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acoustic system, such as a mobile phone, capable of supplying sufficient volume of sound only to a specified user.SOLUTION: A user CU is personally identified by a user sensor 120 with a user element 210 individually carried by the user, and output sound of a parametric speaker 110 is controlled by a directivity control unit 130. As a result, for instance, a desired audio content can be individually output to the user CU without causing annoyance to people nearby.

Description

  The present invention relates to an acoustic system having a mobile phone and the like, and an acoustic device thereof.

  In recent years, demand for portable electronic devices such as mobile phones and notebook computers has been increasing. In such an electronic device, development of a thin portable terminal whose commercial value is an acoustic function such as a videophone, a video playback, and a hands-free phone is being promoted. Under such development, there is an increasing demand for high-quality sound, small size, and thinness for electroacoustic transducers (speaker devices) that are acoustic components.

  Currently, electrodynamic electroacoustic transducers are used as electroacoustic transducers in electronic devices such as mobile phones. This electrodynamic electroacoustic transducer is composed of a permanent magnet, a voice coil, and a diaphragm.

  However, there is a limit to reducing the thickness of electrodynamic electroacoustic transducers due to their operating principles and structures. On the other hand, Patent Documents 1 and 2 describe using a piezoelectric element as an electroacoustic transducer.

  Further, as other examples of the oscillation unit using the piezoelectric element, in addition to a speaker device, there are various acoustic wave sensors (Patent Document 3) that detect a distance to an object using a sound wave oscillated from the piezoelectric element. Is known (Patent Document 4).

No. 2007-026736 Table 2007-083497 Japanese Patent Laid-Open No. 03-270282 JP 2005-165923 A

  At present, cellular phones, which are acoustic systems, have a variety of functions other than calls, such as the ability to view music and movies. Such a mobile phone is used while being placed close to the side of the head during a call, but is used in a state separated from the front of the head when viewing music or movies.

  However, it is not easy to output a sound with a sufficient volume from the mobile phone in such a state. On the other hand, if such a mobile phone outputs a sound with a sufficient volume, it will be a nuisance to the surroundings.

  The present invention has been made in view of the above-described problems, and provides an acoustic system such as a mobile phone that can provide a sound with a sufficient volume only to a specific user.

  The acoustic system of the present invention includes a user element that is individually provided for each user, a speaker unit that outputs sound, a user sensor that detects a user element and personally authenticates the user, and a personally authenticated user Corresponding to the sound control means for controlling the output sound of the speaker unit.

  The acoustic device of the present invention corresponds to a user sensor that detects a user element individually provided for each user and personally authenticates the user, a speaker unit that outputs sound, and a user who is personally authenticated. Voice control means for controlling the output voice of the speaker unit.

  The various components of the present invention do not necessarily have to be independent of each other. A plurality of components are formed as a single member, and a single component is formed of a plurality of members. It may be that a certain component is a part of another component, a part of a certain component overlaps with a part of another component, or the like.

  In the acoustic system of the present invention, personal authentication is performed by a user sensor using user elements individually installed by the user, and the output sound of the speaker unit is controlled by the sound control means. For this reason, for example, it is possible to individually output desired audio contents to the user without causing trouble to the surroundings.

It is a schematic diagram which shows the structure of the acoustic system of embodiment of this invention. It is a typical front view which shows the external appearance of the mobile telephone which is an audio equipment. It is a vertical side view which shows the structure of the principal part of the parametric speaker which is a speaker unit. It is a typical front view which shows the structure of a parametric speaker. It is a flowchart which shows the processing operation of a mobile telephone.

  An embodiment of the present invention will be described with reference to FIGS. The acoustic system 1000 according to the present embodiment includes a user element 210 that is individually provided for each user, and a mobile phone 100 that is an acoustic device.

  The cellular phone 100 includes a parametric speaker 110 that is a speaker unit that outputs sound, a user sensor 120 that detects the user element 210 described above to personally authenticate a user, and a parametric corresponding to a user who has been personally authenticated. And a directivity control unit 130 which is a sound control unit for controlling the output sound of the speaker 110.

  More specifically, as shown in FIG. 2, the mobile phone 100 according to the present embodiment includes a display unit 102 in the upper half of the front surface of the vertically long main body housing 101 and a keyboard unit 103 in the lower half. ing.

  Further, for example, the microphone 141 is individually disposed on the lower right side and the user sensor 120 is individually disposed on the lower left side. A general electrodynamic speaker 160 for calling is disposed at the center of the upper end, and a parametric speaker 110 used for hands-free calling or music viewing is disposed on the side of the speaker.

  As shown in FIG. 1, the user sensor 120 is connected to the directivity control unit 130 via the amplifier circuit 121, and the directivity control unit 130 is connected to the parametric speaker 110.

  In addition, the microphone 141 is connected to a call transmission circuit that wirelessly transmits the input call voice, and the electrodynamic speaker 160 is connected to a call reception circuit that wirelessly receives the call voice and outputs the voice. (Not shown).

  The user element 210 includes, for example, an RFID (Radio Frequency Identification) chip built in the employee batch, and stores at least a user ID for each individual user CU.

  The directivity control unit 130 is composed of LSI (Large Scale Integration) such as ASIC (Application Specific Integrated Circuit), etc., and identifies the user CU for each individual from the detection result of the user element 210 by the user sensor 120, and Identify direction and distance.

  In addition, the directivity control unit 130 acquires a predetermined attribute of the user CU from the detection result of the user element 210. Such user attributes include, for example, an age group, sex, music preference, and the like, and may be recorded in the user element 210 or may be registered in the directivity control unit 130.

  If it is recorded in the user element 210, it is registered for each user ID of the above-described user element 210, and the user ID is searched for. When registered in the user element 210, the registration data is provided to the directivity control unit 130.

  The directivity control unit 130 also serves as a content acquisition unit, and acquires audio content output from the parametric speaker 110. The audio content acquired in this way may be stored in advance in the content acquisition unit, or may be acquired from the outside by wireless communication or the like.

  Therefore, when the user CU is specified for each individual from the detection result of the user element 210 by the user sensor 120 as described above, the directivity control unit 130 performs switching control of the audio content output from the parametric speaker 110.

  Furthermore, when the directivity control unit 130 specifies the direction and distance of the user CU from the detection result of the user element 210 by the user sensor 120 as described above, the directivity control unit 130 controls the sound output direction of the parametric speaker 110 at that position. .

  As shown in FIG. 3, the parametric speaker 110 includes a piezoelectric vibrator 113 in which a piezoelectric element 111 is supported by an elastic member 112, and the elastic member 112 is supported by a highly rigid frame 114.

  As shown in FIG. 4, the parametric speaker 110 has a plurality of piezoelectric vibrators 113 as described above arranged in a matrix. The parametric speaker 110 outputs highly directional sound in a desired direction by individually controlling the drive of the piezoelectric vibrators 113 arranged in a matrix.

The piezoelectric element 111 is not particularly limited as long as it is a material having a piezoelectric effect. However, a material having high electromechanical conversion efficiency, for example, lead zirco-titanate (PZT) is used. Alternatively, a material such as barium titanate (BaTiO ₃ ) can be used.

  The thickness of the piezoelectric element 111 is not particularly limited, but is preferably 10 μm or more and 500 μm or less. For example, when a thin film having a thickness of less than 10 μm is used as a ceramic material that is a brittle material, chipping or breakage occurs due to weak mechanical strength during handling, making handling difficult.

  Further, when a ceramic having a thickness of more than 500 μm is used, the conversion efficiency for converting electric energy into mechanical energy is remarkably lowered, and sufficient performance as the parametric speaker 110 cannot be obtained.

  In general, in a piezoelectric ceramic that generates an electrostrictive effect by inputting an electric signal, the conversion efficiency depends on the electric field strength. Since the electric field strength is expressed by the thickness / input voltage with respect to the polarization direction, an increase in thickness inevitably causes a decrease in conversion efficiency.

  In the piezoelectric element 111 of the present invention, upper / lower electrode layers (not shown) are formed on the main surface in order to generate an electric field. The upper / lower electrode layer is not particularly limited as long as it is a material having electrical conductivity, but it is preferable to use silver or silver / palladium. Silver is used as a general-purpose electrode layer with low resistance, and has advantages in manufacturing process and cost.

  Further, since silver / palladium is a low-resistance material excellent in oxidation resistance, there is an advantage from the viewpoint of reliability. The thickness of the upper / lower electrode layer is not particularly limited, but the thickness is preferably 1 μm or more and 50 μm or less.

  For example, when the thickness is less than 1 μm, since the film thickness is thin, it cannot be uniformly formed, and conversion efficiency may be reduced. As a technique for forming a thin film upper / lower electrode layer, there is a method of applying it in a paste form.

  However, when the piezoelectric element 111 is a polycrystal such as ceramic, the surface state is textured, so that the wet state at the time of application is poor, and there is a problem that a uniform electrode film cannot be formed without a certain thickness.

  On the other hand, when the film thickness of the upper / lower electrode layer exceeds 100 μm, there is no particular problem in manufacturing, but the upper / lower electrode layer becomes a constraining surface for the piezoelectric ceramic material which is the piezoelectric element 111, and energy conversion efficiency There is a problem of lowering.

  The piezoelectric element 111 of the parametric speaker 110 according to the present embodiment has a principal surface on one side constrained by an elastic member 112. The elastic member 112 has a function of adjusting the basic resonance frequency of the piezoelectric element 111. The basic resonance frequency f of the mechanical piezoelectric vibrator 113 depends on the load weight and compliance, as shown by the following equation.

[Equation 1]
f = 1 / (2πL√ (mC))
“M” is mass and “C” is compliance.

  In other words, since the compliance is the mechanical rigidity of the piezoelectric vibrator 113, this means that the fundamental resonance frequency can be controlled by controlling the rigidity of the piezoelectric element 111.

  For example, it is possible to shift the fundamental resonance frequency to a low range by selecting a material having a high elastic modulus or reducing the thickness of the elastic member 112. On the other hand, the fundamental resonance frequency can be shifted to a high range by selecting a material having a high elastic modulus or increasing the thickness of the elastic member 112.

  Conventionally, since the basic resonance frequency is controlled by the shape and material of the piezoelectric element 111, there are problems in design restrictions, cost, and reliability. However, as in the present invention, the elastic member 112, which is a constituent member. Since it can be easily adjusted to a desired fundamental resonance frequency by changing the above, the industrial value is great.

  The elastic member 112 is not particularly limited as long as it is a material having a high elastic modulus with respect to a ceramic that is a brittle material such as metal or resin, but general-purpose materials such as phosphor bronze and stainless steel are used from the viewpoint of workability and cost. used.

  The thickness of the elastic member 112 is preferably 5 μm or more and 1000 μm or less. When the thickness is less than 5 μm, the mechanical strength is weak, the function as a restraining member is impaired, and the processing accuracy is lowered, so that an error in the mechanical vibration characteristics of the piezoelectric element 111 occurs between manufacturing lots.

  In addition, when the thickness exceeds 1000 μm, there is a problem in that the restraint on the piezoelectric element 111 due to the increase in rigidity is strengthened and the vibration displacement amount is attenuated. In addition, the elastic member 112 of the present embodiment preferably has a longitudinal elastic modulus, which is an index indicating the rigidity of the material, of 1 GPa or more and 500 GPa or less. As described above, when the rigidity of the elastic member 112 is excessively low or excessively high, there is a problem that characteristics and reliability are impaired as a mechanical vibrator.

  Hereinafter, the operation principle of the parametric speaker 110 of the present embodiment will be described. The parametric speaker 110 according to the present embodiment radiates ultrasonic waves subjected to AM (Amplitude Modulation) modulation, DSB (Double Sideband modulation) modulation, SSB (Single-Sideband modulation) modulation, and FM (Frequency Modulation) modulation into the air. However, sound reproduction is performed on the principle that audible sound appears due to nonlinear characteristics when ultrasonic waves propagate in the air.

  Non-linearity includes a phenomenon in which the flow changes from laminar flow to turbulent flow when the Reynolds number indicated by the ratio between the inertial action and viscous action of the flow increases. That is, since the sound wave is slightly disturbed in the fluid, the sound wave propagates nonlinearly.

  However, the amplitude of the sound wave in the low frequency band is nonlinear, but the amplitude difference is very small, and is usually handled as a phenomenon of linear theory. On the other hand, nonlinearity can be easily observed with ultrasonic waves, and when radiated into the air, harmonics accompanying the nonlinearity are remarkably generated.

  In summary, sound waves are a dense state where molecular groups are mixed in the air, and if it takes time for the air molecules to recover rather than compress, the air that cannot be recovered after compression is continuously propagated air. This is the principle that an audible sound is generated by colliding with a molecule and generating a shock wave.

  In the configuration as described above, for example, as shown in FIG. 5, the mobile phone 100 according to the present embodiment has a head side surface during a normal call by a user CU not equipped with the user element 210 (step S <b> 1 -Y). The utterance of the user CU is input through the microphone 141 at the lower end, and the utterance of the other user (not shown) is output from the electrodynamic speaker 160 at the upper end (step S10).

  However, when the mobile phone 100 according to the present embodiment detects the user element 210 equipped by the user CU by electromagnetic coupling of RFID or the like (step S2-Y), not only the general usage method as described above ( In step S3-N), for example, in a parametric mode using the parametric speaker 110 (step S4-Y), it is also used for a hands-free call or music viewing.

  In such a case, for example, as shown in FIG. 1, the mobile phone 100 is arranged at a predetermined distance in front of the head of the user CU. In such a state, for example, the user CU inputs a start of hands-free call or music viewing by a predetermined operation or the like.

  Then, the directivity control unit 130 acquires a predetermined attribute of the user CU from the detection result of the user element 210 (step S5). As described above, such user attributes include an age group, sex, music preference, and the like, and may be recorded in the user element 210 or registered in the directivity control unit 130.

  Furthermore, the directivity control unit 130 specifies the direction and distance of the user CU from the detection result of the user element 210 (step S6). Next, the directivity control unit 130 acquires audio content such as music corresponding to the user attribute acquired as described above (step S7).

  Then, such directivity control unit 130 causes the parametric speaker 110 to output audio content and controls the output direction of the highly directional audio of the parametric speaker 110 to the detection position of the user element 210 (step S8).

  In the mobile phone 100 according to the present embodiment, since the sound of the parametric speaker 110 as described above has high directivity, it is possible to provide audio content with sufficient volume to the user CU without causing noise in the surroundings.

  In particular, in the mobile phone 100 of the present embodiment, the user element 210 continues to detect the position of the user CU in real time, and the output direction of the highly directional sound of the parametric speaker 110 is adjusted in real time. For this reason, even if the position of the user CU fluctuates during music viewing or the like, it is possible to accurately provide highly directional sound to the user CU.

  Moreover, the cellular phone 100 according to the present embodiment automatically switches and controls the audio content output from the detection result of the user element 210 as described above. For this reason, even if the user CU does not perform a special sorting operation or the like, it is possible to fully enjoy the audio content that the user CU likes.

  Furthermore, the mobile phone 100 according to the present embodiment is equipped with the parametric speaker 110 used in the parametric mode, separately from the electrodynamic speaker 160 used for normal calls as described above.

  For this reason, a normal call can be executed without any problem by the electrodynamic speaker 160, and highly directional audio content can be provided to the user CU separated from the user CU by a predetermined distance in the parametric mode.

  The present invention is not limited to the present embodiment, and various modifications are allowed without departing from the scope of the present invention. For example, in the above embodiment, the mobile phone 100 switches and controls the audio content to be output corresponding to the detection result of the user element 210.

  However, such a mobile phone 100 may control the frequency characteristics of the output sound of the parametric speaker 110 in accordance with the detection result of the user element 210. For example, since it becomes difficult to hear high frequencies when the elderly person is generally aged, the output sound is shifted to a low frequency and the volume is increased.

  Such an increase in volume can also be realized by changing the frequency characteristics. As described above, since the frequency characteristics that are easy to hear differ depending on the age of the user CU, the frequency characteristics may be changed depending on the age of the user CU.

  Further, the mobile phone 100 may control the output speed of the output sound of the parametric speaker 110 in accordance with the detection result of the user element 210. For example, since the listening speed of voice generally decreases as the elderly gets older, the playback speed of voice content is reduced in such a case.

  Further, in the above embodiment, the user sensor 120 detects the user element 210 and specifies the direction and distance of the user CU, and the directivity control unit 130 performs parametric measurement on the position of the user CU specified by the direction and distance. The control of the sound output direction of the speaker 110 is exemplified.

  However, the user sensor 120 detects the user element 210 and specifies only the direction of the user CU, and the directivity control unit 130 controls the sound output direction of the parametric speaker 110 in the direction of the specified user sensor 120. May be.

  Further, in the above embodiment, as a speaker unit capable of controlling the output direction of highly directional sound, a plurality of piezoelectric vibrators 113 each having a plurality of piezoelectric elements 111 individually supported by a plurality of elastic members 112 are arranged in a matrix. The parametric speaker 110 is illustrated.

  However, it is also possible to implement a speaker unit (not shown) in which one piezoelectric vibrator 113 is supported so as to be swingable in two axial directions such as up, down, left and right, and moved in each direction by a solenoid.

  In the above embodiment, the piezoelectric vibrator 113 has a structure in which the piezoelectric element 111 is supported by the elastic member 112. However, the piezoelectric vibrator may have a laminated structure in which a plurality of ceramic layers and electrode layers are alternately formed.

  Needless to say, the above-described plurality of embodiments and the plurality of modifications can be combined within a range in which the contents do not conflict with each other. In the above-described embodiment, the structure of each part has been specifically described. However, the structure and the like can be variously changed within a range that satisfies the present invention.

DESCRIPTION OF SYMBOLS 100 Mobile phone 101 Main body housing 102 Display unit 103 Keyboard unit 110 Parametric speaker 111 Piezoelectric element 112 Elastic member 113 Piezoelectric vibrator 114 Frame 120 User sensor 121 Amplifying circuit 130 Directivity control part 141 Microphone 160 Electrodynamic type speaker 210 User element 1000 Sound System CU user

Claims (10)

User elements that are individually equipped for each user,
A speaker unit for outputting sound;
A user sensor that detects the user element and personally authenticates the user;
Voice control means for controlling the output voice of the speaker unit corresponding to the user who has been personally authenticated;
An acoustic system. A content acquisition unit for acquiring audio content output from the speaker unit;
The sound system according to claim 1, wherein the sound control unit performs switching control of the sound content to be output.   The acoustic system according to claim 1, wherein the sound control unit controls a frequency characteristic of an output sound of the speaker unit.   The acoustic system according to any one of claims 1 to 3, wherein the sound control unit controls an output speed of an output sound of the speaker unit. The speaker unit is capable of controlling the output direction of highly directional audio,
The user sensor detects the user element and identifies at least a direction of the user;
The sound system according to any one of claims 1 to 4, wherein the sound control unit controls a sound output direction of the speaker unit in a direction of the specified user sensor. The user sensor detects the user element to identify the direction and distance of the user,
The sound system according to any one of claims 1 to 5, wherein the sound control unit controls a sound output direction of the speaker unit to a position of the user specified by a direction and a distance.   The sound according to any one of claims 1 to 6, wherein the speaker unit includes a parametric speaker in which a plurality of piezoelectric vibrators each supporting a plurality of piezoelectric elements with a plurality of elastic members are arranged in a matrix. system.   The acoustic system according to any one of claims 1 to 7, wherein the piezoelectric vibrator has a laminated structure in which a plurality of ceramic layers and electrode layers are alternately formed.   The acoustic system according to any one of claims 1 to 8, wherein the piezoelectric vibrator oscillates an ultrasonically modulated ultrasonic wave. A user sensor for detecting a user element individually provided for each user and personally authenticating the user;
A speaker unit for outputting sound;
Voice control means for controlling the output voice of the speaker unit corresponding to the user who has been personally authenticated;
Audio equipment.

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