JP2018142878A - Voice transmission method, sound wave generator and voice transmission apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a voice transmission method enabling a speaker to know how a listener hears the speaker's voice even when the voice is uttered toward the listener as a sound wave with directivity.SOLUTION: The voice transmission method, capable of making a listener H2 listen to a voice uttered by a speaker H1, converts the voice uttered by the speaker into an electric signal and generates a sound wave as an audible sound corresponding to the converted electric signal toward the head of the listener through sound wave generators 11, 16 generating a sound wave with directivity. Moreover, the voice transmission method notifies the speaker of a state of the sound wave reaching the head of the listener through notification devices 12, 16.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sound transmission method that allows a listener to hear a voice uttered by a speaker, and a sound wave generation device and a sound transmission device that are directly used to implement the sound transmission method.

  Conventionally, in a sound wave generator that generates a sound wave as an audible sound, for example, as shown in Patent Document 1, an ultrasonic wave having directivity generated by a vibration unit such as an ultrasonic vibrator is used as an audible sound. A technique for generating a sound wave of a specific direction in a specific direction has been proposed.

Japanese Patent Laid-Open No. 11-24620

  Such a sound wave generator is not limited to the generation of sound waves according to store information and various advertisements as described in Patent Document 1, but may be applied to a window service for a visitor whose hearing has deteriorated. For example, if the volume of the person in charge at the window (ie, the speaker) is increased and heard as a sound wave having the above-mentioned directivity for a listener who has visited the window, the volume of the voice is increased. Only the voice of the contact person can be heard by other visitors.

  However, when a sound wave having directivity as described above is generated only for the listener, there arises a problem that the speaker does not know how his / her voice is heard by the listener. The present invention has been made in view of these problems, and how a speaker's voice is heard by the listener even when the speaker's voice is generated as a directional sound wave toward the listener. It was made for the purpose of providing a voice transmission method that the speaker can know. Another object of the present invention is to provide a sound wave generator and a sound transmission device that are directly used for carrying out the sound transmission method.

  The voice transmission method of the present invention is a voice transmission method for listening to a listener (H2) a voice uttered by a speaker (H1), wherein the voice uttered by the speaker is converted into an electrical signal, and the converted A sound wave as an audible sound according to an electric signal is generated toward a head of the listener via a sound wave generator that generates a sound wave having directivity, and the state of the sound wave reaching the head of the listener is The speaker is notified through the notification device (12, 16, 73, 75A).

  As described above, in the present invention, the voice uttered by the speaker (that is, the voice of the speaker) is converted into an electrical signal and then converted into an audible sound having directivity through the sound wave generator. Generated toward the head. For this reason, only the listener can hear the voice corresponding to the sound wave generated by the sound wave generator, and only the live voice of the speaker can be heard by others around the listener. Further, the speaker can know how the voice of the speaker is heard by the listener by notifying the state of the sound wave that reaches the head of the listener via the notification device.

  Note that in such a sound transmission method using the sound wave generator, it is desirable to prohibit the generation of sound waves by the sound wave generator by turning off the power when the method is not necessary. In that case, sound waves can be generated from the sound wave generator only when necessary, such as when the listener's hearing is reduced. However, when the sound wave generator generates sound waves having directivity using ultrasonic waves, annoying noise is generated as an audible sound at the start of energization.

  Therefore, it is desirable that the sound wave generator directly used for carrying out the sound transmission method includes the following sound wave generators (11, 12) and a voltage controller (16). The sound wave generation unit is configured to generate sound waves as audible sound having directivity by vibrating the vibration unit (111) that vibrates in response to voltage application to generate ultrasonic waves. The voltage control unit is configured to suppress generation of noise as an audible sound at the start of energization of the vibration unit by controlling a voltage applied to the vibration unit.

  According to such a configuration, at the start of energization to the vibration unit (that is, when the sound wave generator is started up), the voltage control unit controls the voltage applied to the vibration unit, so that noise as audible sound is generated. Can be suppressed.

  In addition, the code | symbol in the parenthesis described in this column and a claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this invention is shown. It is not limited.

It is a schematic diagram showing the structure of the window as an audio | voice transmission apparatus of 1st Embodiment. It is an external view which represents typically the structure of the speaker provided in the window. It is a rear view which represents typically the detailed structure of the speaker. It is a side view which represents typically the detailed structure of the speaker. It is explanatory drawing which represents typically the structure of the ultrasonic element in the speaker. It is a block diagram which represents typically the structure of the control system of the speaker. It is a graph showing the relationship between time and noise in the speaker. It is a schematic diagram showing the structure of the window as a sound transmission apparatus of 2nd Embodiment. It is a schematic diagram showing the structure of the window as an audio | voice transmission apparatus of 3rd Embodiment. It is explanatory drawing showing arrangement | positioning of the reflecting plate in the audio | voice transmission apparatus. It is a circuit diagram showing the structure of the indicator in the audio | voice transmission apparatus. It is a schematic diagram showing the structure of the window as an audio | voice transmission apparatus of 4th Embodiment. It is explanatory drawing showing arrangement | positioning of the microphone in the audio | voice transmission apparatus.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[1. First Embodiment]
[1-1. Overall configuration of window]
A window 1 shown in FIG. 1 is an indoor space provided with a floor 2 and a ceiling 3. On the floor 2, a desk 4 is placed, and a chair 5 for a speaker H1 to sit and a chair 6 for a listener H2 to sit are opposed to each other with the desk 4 interposed therebetween. In addition, this window 1 may be a consultation window for a government office, a bank, a travel agency, or the like, or may be another window. In the window 1, a soundproof wall 7 is provided at least behind the speaker H1 and the chair 5. The soundproof wall 7 may be provided behind the listener H2, a general wall that is not a soundproof wall may be provided behind the listener H2, and the back of the listener H2 may be opened outdoors. .

  In the window 1, ultrasonic speakers 11 and 12 are provided on the ceiling 3 in order to cope with the case where the hearing of the listener H2 is reduced. Although the configurations of the ultrasonic speakers 11 and 12 will be described in detail later, both are configured to generate sound waves as audible sounds to which directivity is imparted by using ultrasonic waves. The range in which the audible sound generated from the ultrasonic speaker 11 reaches is set so as to encompass almost the entire head of the listener H2 sitting on the chair 6, as indicated by a broken line in FIG. In addition, the range in which the audible sound generated from the ultrasonic speaker 12 reaches is set so as to cover almost the entire head of the speaker H1 sitting on the chair 5.

  It is preferable that the distance D1 from the ultrasonic speaker 12 to the head of the speaker H1 and the distance D2 from the ultrasonic speaker 11 to the head of the listener H2 are both 1.5 m or more. The ultrasonic speaker 11 may be provided with a cylindrical guide plate 13 (that is, a hood) as illustrated in FIG. 2 in order to improve the directivity of the sound wave as an audible sound. Similarly, a cylindrical guide plate 14 may be provided on the ultrasonic speaker 12. Further, the guide plates 13 and 14 may have a conical shape (that is, a cone shape) or other shapes. Further, the guide plates 13 and 14 may be omitted.

  Returning to FIG. 1, on the desk 4, a microphone 15 for converting the voice uttered by the speaker H <b> 1 into an electrical signal is arranged. From the ultrasonic speakers 11, 12, sound waves corresponding to the electric signals converted by the microphone 15 are generated. That is, the window 1 can be heard directly by the speaker H1 from the voice of the listener H2, but the voice of the voice of the speaker H1 cannot be heard from the listener H2 via the microphone 15 and the ultrasonic speaker 11, and the listener H2. It is configured to cope with the case that cannot be heard.

  In addition, a control circuit 16 that controls electric signals from the microphone 15 to the ultrasonic speakers 11 and 12 is provided on the speaker H1 side on the lower surface of the top plate of the desk 4. Further, on the upper surface of the floor 2 below the desk 4, a switch 17 that can be operated by the speaker H1 with a foot or the like is provided. The switch 17 is a main switch that switches whether power can be supplied to the entire electrical system according to the configuration from the microphone 15 to the ultrasonic speakers 11 and 12 (that is, whether the power is on / off). Further, on the upper surface of the floor 2 including the lower sides of the chairs 5 and 6, sound absorbing materials 18 and 19 for absorbing the sound waves that have passed around the head of the speaker H1 or the listener H2 are laid.

[1-2. Detailed configuration of the speaker]
Next, a detailed configuration of the ultrasonic speakers 11 and 12 will be described. In addition, since the ultrasonic speakers 11 and 12 are configured in substantially the same manner, the ultrasonic speaker 11 will be described below as an example. As shown in FIG. 3, the ultrasonic speaker 11 has a configuration as an ultrasonic element array in which a plurality of ultrasonic elements (that is, ultrasonic transducer elements) 11A are arranged in a planar shape. Hereinafter, the surface on which the ultrasonic elements 11A are arranged in a plane is referred to as an array surface.

  Each ultrasonic element 11A generates a sound wave from the back side (that is, one side of the array surface) with respect to the paper surface of FIG. 3, and the front side of the paper surface of FIG. That is, the electrode 11B is disposed so as to protrude from the other side of the array surface. The electrode 11B is a so-called pin for applying a voltage to each of the ultrasonic elements 11A. In the example of FIG. 3, each ultrasonic element 11 </ b> A has an outer shape configured in a cylindrical shape, is arranged so that the axis of the cylinder is orthogonal to the array surface, and for each ultrasonic element 11 </ b> A A maximum of six ultrasonic elements 11A are provided in close contact with the periphery thereof. In addition, the method of arrange | positioning the ultrasonic element 11A so that the other ultrasonic element 11A may contact the circumference | surroundings of each ultrasonic element 11A is not limited to this. For example, the ultrasonic elements 11A may be arranged so as to be adjacent vertically and horizontally, or may be arranged by other methods.

  In addition, each ultrasonic element 11A is arranged such that each electrode 11B forms a column for each polarity with the electrode 11B of the other ultrasonic element 11A. Each column of the electrodes 11B is provided with a conductor 11C for energizing the electrodes 11B in the column. That is, the electrodes 11B of each ultrasonic element 11A are + and − fastened together by the conductor 11C. For this reason, each conductor 11C is arrange | positioned in parallel. A voltage is applied to each conductor 11C from the control circuit 16 via the electric wire 22.

  Further, as schematically shown in FIG. 4 as viewed from the side in FIG. 3, each conductor 11C has a short side (that is, a plate width direction) in the protruding direction of the electrode 11B, and is formed on the array surface. It is comprised by the rectangular-plate-shaped metal plate which has a long side in the direction along. For this reason, each conductor 11C exhibits a shape like a heat sink fin of a heat sink as a whole. Therefore, in the ultrasonic speaker 11 in the present embodiment, as shown in FIG. 3, the fan 24 that is rotationally driven by the motor 23 is arranged so that the blowing direction is along the long side direction of each conductor 11C. Here, it is desirable that the plate width direction of each conductor 11C be perpendicular to the array surface, but it is not necessarily limited to the vertical in the strict sense. Also good.

  Further, the ultrasonic element 11A has a configuration in which a piezoelectric layer 112 is laminated on a membrane 111, as schematically shown in FIG. The membrane 111 may be a metal thin plate, a ceramic thin plate such as silica or zirconia, a thin plate formed by laminating them, or another thin plate. The piezoelectric layer 112 may be made of piezoelectric ceramics or may be made of other piezoelectric materials.

  When an AC power supply 120 is connected to the piezoelectric layer 112, for example, an AC voltage is applied, whereby the piezoelectric layer 112 repeatedly expands and contracts along the surface of the membrane 111. As a result, vibration is generated in the membrane 111. When a frequency signal corresponding to ultrasonic waves is applied as a voltage to the piezoelectric layer 112, the ultrasonic element 11A generates ultrasonic waves.

  In addition, as shown in Patent Document 1, a parabolic reflector or the like may be provided in the array constituted by the ultrasonic elements 11A as necessary, and the reflected waves may be used. Needless to say.

  Next, as shown in FIG. 6, the control circuit 16 includes an ultrasonic modulation unit 16A and an ultrasonic drive amplifier 16B. A frequency signal corresponding to an audible sound is input from the sound source 30 such as the microphone 15 to the ultrasonic modulator 16A. Note that the sound source 30 is not limited to the microphone 15 and may be one that inputs a frequency signal of a sound recorded in advance on a recording medium, such as a music media player.

  The ultrasonic modulation unit 16A is a circuit that modulates a frequency signal corresponding to an audible sound input from the sound source 30 into a frequency signal corresponding to an ultrasonic wave. For example, the ultrasonic modulation unit 16A may correspond to an audible sound with a change in amplitude of a voltage oscillated at a frequency corresponding to the ultrasonic wave, or may be modulated by other methods.

  The ultrasonic drive amplifier 16B drives the ultrasonic speakers 11 and 12 based on the ultrasonic signal modulated by the ultrasonic modulation unit 16A. That is, the ultrasonic drive amplifier 16 </ b> B controls the voltage applied to the ultrasonic speakers 11 and 12 to generate ultrasonic waves obtained by modulating the frequency signal from the ultrasonic speakers 11 and 12.

  The control circuit 16 includes a fan 16D driven by a motor 16C, and the ultrasonic modulation unit 16A and the ultrasonic drive amplifier 16B are cooled by the wind generated by the fan 16D.

  Here, when a voltage is applied to the ultrasonic speaker 11 in order to generate ultrasonic waves, normally, at the time of start-up (that is, at the start of energization), a large noise (that is, possible) as shown by a broken line L1 in FIG. Noise). This is because the temperature of the membrane 111 is low at the time of start-up, and the temperature does not rise uniformly, so that the sound wave generated by each ultrasonic element 11A varies from element to element and reaches an audible sound until reaching 40 KHz. Presumed to occur. On the other hand, after time T when it can be considered that the temperature of the membrane 111 has risen above the predetermined temperature, the noise becomes small.

  Therefore, the control circuit 16 in the present embodiment lowers the applied voltage to the ultrasonic speakers 11 and 12 before time T when the temperature of the membrane 111 can be considered to be lower than the predetermined temperature, compared to after time T. It is configured using a timer or the like. Such a configuration may be achieved by hardware circuit design in the control circuit 16, or may be achieved by software processing by providing the microcomputer with the CPU, ROM, and RAM. Good.

  Further, the control circuit 16 includes a power lamp (not shown), and is configured to blink the power lamp when starting up before the time T and to turn on (that is, turn on) the power lamp when steady after the time T. ing.

[1-3. effect]
According to the first embodiment described in detail above, the following effects can be obtained.
(1A) In the window 1, the volume of the voice of the person in charge at the window (ie, the speaker H1) is increased to the head of the listener H2 who has visited, and the sound wave having the directivity as described above is heard. Can. In that case, only the listener can hear the voice whose volume has been increased, and the other visitors can hear only the voice of the person in charge of the window. When using a well-known audio information transmission device facing the listener H2 in front of the eyes, it will be known to the surroundings that the hearing of the listener H2 has deteriorated. A sound wave having directivity is generated pinpoint from the ultrasonic speaker 11 provided at a position away from the listener H2. For this reason, it is difficult for the surroundings to understand that the hearing of the listener H2 is reduced.

  Moreover, since the ultrasonic speakers 11 and 12 are provided on the ceiling 3 and generate sound waves obliquely downward from a position 1.5 m or more away from the speakers H1 and H2, the hearing of the listener H2 is not lowered. However, the window 1 can be used without a sense of incongruity. In addition, the direction in which the ultrasonic speakers 11 and 12 generate sound waves may be directly below, and in this case, the same effect is produced.

  (1B) Further, a sound wave similar to the sound wave generated from the ultrasonic speaker 11 toward the listener H2 is generated from the ultrasonic speaker 12 to the pinpoint toward the speaker H1. For this reason, the speaker H1 can know how his / her voice is heard by the listener H2. Therefore, the speaker H1 can confirm whether the listener H2 can hear his / her voice, and can perform smooth communication. Further, even when the switch 17 is in an off state and the sound of a sufficient volume is not transmitted to the listener H2, the speaker H1 can notice early. For this reason, since common understanding arises between the speaker H1 and the listener H2, smooth communication can be implemented. In addition, when directivity and a noise canceller function are given to the microphone 15, smoother communication may be performed.

  (1C) In this embodiment, whether or not sound waves can be generated by the ultrasonic speakers 11 and 12 can be switched according to an operation on the switch 17 disposed at a position that can be operated by the speaker H1. For this reason, when the hearing of the listener H2 is not deteriorated and it is not necessary to use the ultrasonic speakers 11 and 12, the power can be turned off to save power consumption. When the switch 17 can individually switch on / off the power of the ultrasonic speakers 11 and 12, the speaker H1 can confirm that his / her voice is heard by the listener H2, and then the ultrasonic wave The power of the speaker 12 may be turned off.

  (1D) In the present embodiment, when the membrane 111 such as the ultrasonic element 11A is considered to be less than a predetermined temperature, the voltage applied to the ultrasonic speakers 11 and 12 is lower than that in the steady state. For this reason, as shown by a solid line L2 in FIG. 7, it is possible to suppress the generation of noise (ie, beat) as an audible sound at the time of startup.

  (1E) In addition, in this embodiment, the power lamp blinks at the time of start-up when the applied voltage to the ultrasonic element 11A is suppressed, and the power lamp is lit at the normal time when the normal voltage is applied. For this reason, the speaker H1 can know that the sound wave is not transmitted at a sufficient volume from the ultrasonic speaker 11 toward the listener H2 when the power lamp is blinking.

  (1F) Moreover, in this embodiment, since the ultrasonic element 11A is cooled via the fan 24, the temperature rise of the ultrasonic element 11A can be suppressed. In this embodiment, since the ultrasonic drive amplifier 16B is cooled via the fan 16D, the temperature increase of the ultrasonic drive amplifier 16B can be suppressed. That is, generally, when a sound wave generator that generates ultrasonic waves is used continuously for a long time, there is a problem that both the amplifier and the speaker generate heat at a high temperature. On the other hand, in this embodiment, the temperature rise of the ultrasonic drive amplifier 16B and the ultrasonic speakers 11 and 12 as a part of the control unit (that is, the control circuit 16) can be satisfactorily suppressed.

  (1G) In particular, the ultrasonic speaker 11 as a sound wave generator has a configuration as an ultrasonic element array in which a plurality of ultrasonic elements 11A are arranged in a plane, and is supersonic from one side of the array surface. Each of the sound wave elements 11A generates a sound wave, and each of the ultrasonic wave elements 11A protrudes from the other side of the array surface. In addition, the plurality of conductors 11C for energizing each of the electrodes 11B are arranged in parallel to each other along the blowing direction by the motor 23 and the fan 24 as a blower, and in the plate width direction in the direction intersecting the array surface Each is configured in a plate shape having For this reason, each conductor 11C can efficiently radiate the heat generated in the ultrasonic element 11A via the electrode 11B, like the heat radiation fin of the heat sink. As described above, such an effect also occurs in the ultrasonic speaker 12.

  (1H) The window 1 is provided at least in part of the reach of the sound wave that has passed around the heads of the speaker H1 and the listener H2, and includes a soundproof wall 7 and sound absorbing materials 18 and 19 that absorb the sound wave. And more. For this reason, the sound wave that hits the body of the listener H2 or the chair 6 is reflected to the speaker H1 side, but the sound wave that hits the sound absorbing materials 18 and 19 and the sound barrier 7 is absorbed and does not reach other than the speaker H1. . For this reason, it is further difficult to understand that the hearing of the listener H2 is reduced.

  In addition, the voice guidance device such as the window 1 is relatively unattractive when used outdoors, but when used indoors, as a result of reflection of sound waves radiated by walls due to the characteristics of ultrasonic waves, the speaker H1 and the listener H2 There is a risk that even people who do not want to hear their conversations will be told. On the other hand, in this embodiment, it is possible to satisfactorily prevent a conversation between the speaker H1 and the listener H2 from being heard by a third party, and a conversation with high confidentiality can be performed between the parties concerned. .

[1-4. Correspondence with Claimed Elements]
In the embodiment, the ultrasonic speakers 11 and 12 correspond to the sound wave generator, the ultrasonic speaker 12 and the control circuit 16 correspond to the notification device, and the ultrasonic speaker 11 and the control circuit 16 correspond to the sound wave generator. To do. Further, the membrane 111 and the piezoelectric layer 112 correspond to a vibration part, and the control circuit 16 corresponds to a voltage control part. Further, the motor 16C and the fan 16D, and the motor 23 and the fan 24 correspond to a blower. The sound barrier 7 and the sound absorbing materials 18 and 19 correspond to the sound absorbing material.

[2. Second Embodiment]
[2-1. Difference from the first embodiment]
Since the basic configuration of the second embodiment is the same as that of the first embodiment, the description of the common configuration will be omitted, and the description will focus on the differences. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  In the first embodiment described above, the on / off of the power source of the ultrasonic speakers 11 and 12 and the like is switched by the switch 17, but the window 51 of the second embodiment, as shown in FIG. The difference is that a pressure sensor 61 for switching between the two is provided on the chair 6. That is, in this embodiment, even if the switch 17 is turned on, the power of the ultrasonic speakers 11 and 12 and the like is turned on when the pressure sensor 61 detects that the listener H2 is sitting on the chair 6. Thus, the control circuit 16 is configured. Conversely, when the pressure sensor 61 detects that the listener H2 is not sitting on the chair 6, the control circuit 16 is configured so that the power of the ultrasonic speakers 11, 12 and the like is turned off.

[2-2. effect]
According to the second embodiment described in detail above, the following effects are obtained in addition to the effects (1A) to (1H) of the first embodiment described above.

  (2A) In this embodiment, it is possible to prevent the ultrasonic speakers 11, 12 and the like from being kept on even though the listener H2 is not sitting on the chair 6, and to further reduce power consumption. You can save well. In the second embodiment, the pressure sensor 61 corresponds to a detection unit, and the control circuit 16 corresponds to a prohibition control unit.

[3. Third Embodiment]
[3-1. Difference from the first embodiment]
Since the basic configuration of the third embodiment is the same as that of the first embodiment, the description of the common configuration will be omitted, and the description will focus on the differences. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is referred to.

  In the first embodiment described above, the ultrasonic speaker 12 notifies the speaker H1 of the state of the sound wave that reaches the head of the listener H2. However, as shown in FIG. The difference is that the sonic speaker 12 is omitted and a reflector 73 and an indicator 75 are provided instead.

  The indicator 75 has a columnar configuration standing on the desk 4, and a plurality of lamps 75A are provided on the side surface. In the example of FIG. 9, five lamps 75A are provided, but any number of lamps 75A may be provided as long as it is two or more. The colors of the lamps 75A may be different or the same.

  In addition, a reflector 73 is provided on the headrest 6 </ b> A provided on the upper portion of the backrest of the chair 6. As shown in FIG. 10, the reflector 73 is attached to the headrest 6 </ b> A so as to be disposed on both the left and right sides of the head of the listener H <b> 2 sitting on the chair 6. Further, as indicated by an arrow A in FIG. 9, the reflection plate 73 is disposed so as to reflect the sound wave that has arrived from the ultrasonic speaker 11 toward the lower part of the indicator 75.

  A microphone 75 </ b> B shown in FIG. 11 is provided below the indicator 75. A control circuit 75C is provided inside the indicator 75, and the control circuit 75C changes the lighting state of the lamp 75A according to the volume of the sound wave input to the microphone 75B.

[3-2. effect]
According to the third embodiment described in detail above, in addition to the effects (1A) and (1C) to (1H) of the first embodiment described above, the following effects can be obtained.

  (3A) In the present embodiment, the speaker H1 can check how loud his / her voice is heard by the listener H2 by referring to the lighting state of the lamp 75A of the indicator 75. For this reason, the effect similar to the effect (1B) of 1st Embodiment is acquired.

  (3B) Further, in the present embodiment, the volume of the sound wave that has actually reached the head of the listener H2 is obtained via the reflectors 73 arranged on both sides of the head of the listener H2, and the volume is obtained by the speaker. H1 can be notified. For this reason, when the speaker H2 does not hear the voice of the speaker H1, the speaker H1 can also grasp whether the axis of the sound is slightly shifted. In the present embodiment, the reflector 73 and the microphone 75B correspond to the volume acquisition unit.

[4. Fourth Embodiment]
[4-1. Difference from the third embodiment]
Since the basic configuration of the fourth embodiment is the same as that of the third embodiment, the description of the common configuration will be omitted, and differences will be mainly described. In addition, the same code | symbol as 3rd Embodiment shows the same structure, Comprising: Prior description is referred.

  In the third embodiment described above, the reflectors 73 are provided on the left and right sides of the head of the listener H2 in the headrest 6A of the chair 6, but the window 81 of the third embodiment is as shown in FIGS. The difference is that the microphone 83 is provided instead of the reflector 73 and the ultrasonic speaker 12 is provided as in the first embodiment. In the examples of FIGS. 12 and 13, three microphones 83 are provided on the left and right sides of the head of the listener H2, but one or two microphones may be provided, or four or more may be provided. . However, when a plurality of microphones 83 are provided above and below, the microphones 83 corresponding to the seating height of the listener H2 can be used. The ultrasonic speaker 11 is most easily heard by the listener H2 provided immediately above the listener H2. However, when the ultrasonic speaker 11 is provided obliquely above the listener H2 as in the present embodiment, a microphone corresponding to the sitting height is provided. Preferably 83 is used.

  In the present embodiment, the control circuit 75C provided in the indicator 75 changes the lighting state of the lamp 75A according to the volume of the sound wave input to the microphone 83, instead of using the microphone 75B described above.

[4-2. effect]
According to the fourth embodiment described in detail above, the effects (1A) to (1H) of the first embodiment and the effects (3A) and (3B) of the third embodiment are obtained.

  (4A) Further, unlike the third embodiment, since the reflection of sound waves is not used, it is possible to suppress the voice of the speaker H1 from being echoed unnecessarily. In the present embodiment, the microphone 83 corresponds to the volume acquisition unit.

[5. Other Embodiments]
As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to the above-mentioned embodiment, It can implement in various deformation | transformation.

  (5A) In each of the above embodiments, the applied voltage to the ultrasonic speakers 11 and 12 is lowered before the time T at which the temperature of the membrane 111 can be considered to have risen above a predetermined temperature, but the ultrasonic speaker while reducing noise. The method of energizing 11 and 12 is not limited to this. For example, before the time T, the polarity of the voltage applied to the piezoelectric layer 112 may be maintained in a certain direction. Even when such energization is performed, the temperature of the membrane 111 rises in response to the energization while maintaining the slid state. Prior to time T, the polarity of the voltage applied to the piezoelectric layer 112 may be changed at a high speed that the membrane 111 cannot follow.

  (5B) In each of the above embodiments, the ultrasonic element 11A is configured by laminating the piezoelectric layer 112 on the membrane 111. However, the present invention is not limited to this. For example, an ultrasonic element of a type that energizes the electromagnetic coil to vibrate the membrane may be used. Even in that case, energization may be performed before the time T by the method shown in the above embodiments or the method shown in (5A). In particular, when the voltage polarity is maintained in a certain direction, the temperature of the ultrasonic element can be increased more favorably by using the coil like a nichrome wire, and the time T may be advanced.

  (5C) In each of the above embodiments, the energization period as shown in (5A) and (5B) is set before time T. However, the present invention is not limited to this. For example, the temperature of the membrane 111 may be measured directly until reaching a predetermined temperature, or the time T may be changed according to the outside air temperature.

  (5D) In each of the above embodiments, the power of the ultrasonic speakers 11 and 12 and the like is turned on / off according to the operation of the switch 17 or the state of the pressure sensor 61, but the present invention is not limited to this. For example, the on / off may be controlled according to the presence or absence of an input sound to the microphone 15. In that case, the power consumption can be saved even better.

  (5E) In the third embodiment, the volume of the sound wave reflected by the reflecting plate 73 is measured via the microphone 75B, but the present invention is not limited to this. For example, the reflection plate 73 may be disposed so as to reflect the sound wave generated from the ultrasonic speaker 11 toward the head of the speaker H1. In this case, the speaker H1 can directly hear the voice of the speaker H1 himself listening to the listener H2, and can better know the state of the sound wave reaching the head of the listener H2.

  (5F) In 3rd Embodiment and 4th Embodiment, although the reflecting plate 73 or the microphone 83 was fixed to the headrest 6A, it is not limited to this. For example, the elevation angle of the reflector 73 or the microphone 83 may change according to the seating height of the listener H2. Further, the reflection plate 73 or the microphone 83 may be provided at the upper end of the backrest or the like. In that case, the above-described configuration can be applied even when the chair 6 does not have the headrest 6A.

  (5G) In each of the embodiments described above, the switch 17 is disposed at the foot of the speaker H1 and the control circuit 16 is disposed on the lower surface of the desk 4, but this is not a limitation. For example, the switch 17 may be arranged in the hand of the speaker H1. Further, the control circuit 16 can be arranged at an arbitrary position, and may be arranged at a position away from the speaker H1. However, maintenance or the like may be easier if the control circuit 16 is arranged near the speaker H1.

  (5H) In each of the above embodiments, the present invention is applied to the window where the chairs 5 and 6 are arranged with the desk 4 interposed therebetween, but the present invention is not limited to this. For example, the speaker H1 may be away from the listener H2, such as the second floor. In addition, the sound transmission method, the sound wave generation device, and the sound transmission device of the present invention may be used outdoors, and the floor 2, the ceiling 3, the soundproof wall 7, the sound absorbing materials 18, 19 and the desk in each of the above embodiments. 4 or at least one or more of the chairs 5 and 6 may be omitted.

  (5I) A plurality of functions of one constituent element in the embodiment may be realized by a plurality of constituent elements, or a single function of one constituent element may be realized by a plurality of constituent elements. . Further, a plurality of functions possessed by a plurality of constituent elements may be realized by one constituent element, or one function realized by a plurality of constituent elements may be realized by one constituent element. Moreover, you may abbreviate | omit a part of structure of the said embodiment. In addition, at least a part of the configuration of the embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified only by the wording described in the claim are embodiment of this invention.

  (3H) Non-transitional actual recording medium such as a system having the audio transmission device as a constituent element, a program for causing a computer to function as the audio transmission device, a semiconductor memory in which the program is recorded, in addition to the audio transmission device The present invention can also be realized in various forms.

DESCRIPTION OF SYMBOLS 1,51,71,81 ... Window 5,6 ... Chair 6A ... Headrest 7 ... Sound barrier 11, 12 ... Ultrasonic speaker 11A ... Ultrasonic element 11B ... Electrode 11C ... Conductor 15, 75B, 83 ... Microphone 16, 75C ... Control circuit 16A ... Ultrasonic modulator 16B ... Ultrasonic drive amplifier 16C, 23 ... Motor 16D, 24 ... Fan 17 ... Switch 18, 19 ... Sound absorbing material 61 ... Pressure sensor 73 ... Reflector 75 ... Indicator 75A ... Lamp 111 ... Membrane 112 ... piezoelectric layer H1 ... speaker H2 ... listener

Claims (17)

A voice transmission method for listening to the listener (H2) the voice uttered by the speaker (H1),
Converting the voice uttered by the speaker into an electrical signal;
A sound wave as an audible sound corresponding to the converted electrical signal is generated toward the head of the listener via a sound wave generator (11, 16) that generates a directional sound wave,
A voice transmission method for notifying the speaker of the state of the sound wave that reaches the head of the listener via a notification device (12, 16, 73, 75A).   The voice transmission method according to claim 1, wherein the voice transmission method switches whether or not sound waves can be generated by the sound wave generator according to an operation on a switch (17) arranged at a position operable by the speaker. . A sound wave generator (11, 12) configured to generate a sound wave as an audible sound having directivity by vibrating a vibration part (111, 112) that vibrates in response to voltage application to generate an ultrasonic wave. )When,
A voltage control unit (16) configured to suppress the generation of noise as an audible sound at the start of energization to the vibrating unit by controlling the voltage applied to the vibrating unit;
A sound wave generator comprising: The sound wave generator according to claim 3,
The voltage control unit is configured to apply a lower voltage to the vibrating unit when the temperature of the vibrating unit can be considered to be lower than a predetermined temperature, compared to when the temperature can be considered to be equal to or higher than the predetermined temperature. Sound wave generator. The sound wave generator according to claim 3,
When the temperature of the vibration unit can be regarded as being lower than a predetermined temperature, the voltage control unit is a sound wave generator configured to maintain the polarity of the voltage applied to the vibration unit in a certain direction. The sound wave generator according to claim 3,
When the temperature of the vibration part can be regarded as being lower than a predetermined temperature, the voltage control part is configured to change the polarity of the voltage applied to the vibration part at a high speed that the vibration part cannot follow. Sound wave generator. It is a sound wave generator of any one of Claims 3-6,
The sound wave generator further provided with the air blower (16C, 16D, 23, 24) comprised so that the said sound wave generation part or the said voltage control part might be cooled. The sound wave generator according to claim 7,
The sound wave generation unit (11) has a configuration as an ultrasonic element array in which a plurality of ultrasonic elements (11A) are arranged in a plane, and each of the ultrasonic elements from one side of the surface. An acoustic wave is generated, and each of the ultrasonic elements protrudes an electrode (11B) for applying the voltage from the other side of the surface,
A plurality of conductors (11C) for energizing each of the electrodes are arranged in parallel to each other along the blowing direction by the blower, and in a plate shape having a plate width direction in a direction intersecting the surface, respectively. Configured sound wave generator. A voice transmission device (1, 51, 71, 81) for listening to the listener (H2) the voice uttered by the speaker (H1),
A microphone (15) configured to convert speech uttered by the speaker into an electrical signal;
A sound wave generator (11, 16) configured to generate a sound wave as an audible sound according to the converted electrical signal as a directional sound wave toward the head of the listener;
A notification device (12, 16, 73, 75A) configured to notify the speaker of the state of the sound wave that reaches the head of the listener;
An audio transmission device comprising: The voice transmission device according to claim 9,
An audio transmission device further comprising a sound absorbing material (7, 18, 19) that is provided in at least a part of the reach of the sound wave that has passed around the head and absorbs the sound wave. The voice transmission device (1) according to claim 9 or 10,
The notification device (12, 16) is a voice transmission device configured to generate a sound wave similar to the sound wave generated by the sound wave generation device toward the head of the speaker as a sound wave having directivity. The voice transmission device (71, 81) according to claim 9 or 10,
A volume acquisition unit (73, 75B, 83) configured to acquire the volume of the sound wave reaching the head;
In addition,
The notification device (75A) is a voice transmission device configured to notify the speaker of the volume acquired by the volume acquisition unit. A voice transmission device (71) according to claim 12,
A chair (6) with a backrest configured to allow the listener to sit down;
In addition,
The volume acquisition unit
A reflector (73) provided on the upper part of the back of the chair;
A microphone (75B) configured to acquire sound waves reflected by the reflector;
An audio transmission device comprising: An audio transmission device (81) according to claim 12,
A chair (6) with a backrest configured to allow the listener to sit down;
In addition,
The volume acquisition unit
A microphone (83) provided at the top of the chair back and configured to acquire sound waves;
Provided voice transmission device. The voice transmission device (71) according to claim 9 or 10,
A chair (6) with a backrest configured to allow the listener to sit down;
In addition,
The notification device includes a reflector (73) provided on an upper part of a backrest of the chair and configured to reflect sound waves generated from the sound wave generator toward the speaker.
Provided voice transmission device. The voice transmission device (51) according to any one of claims 9 to 15,
A chair (6) configured to seat said listener;
A detection unit (61) configured to detect whether the listener is sitting in the chair;
When the detection unit detects that the listener is sitting, the sound generation device permits generation of sound waves, and when the detection unit detects that the listener is not sitting, generation of the sound waves. A prohibition control unit (16) configured to prohibit
An audio transmission device further comprising: The voice transmission device (1, 51, 71, 81) according to any one of claims 9 to 15,
A switch (17) arranged at a position operable by the speaker and configured to switch whether or not to generate sound waves by the sound wave generator;
An audio transmission device further provided.

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