JP2022133021A - Conference support system - Google Patents

Abstract

To provide an indication as to how to amplify and reproduce in a conference support system to properly communicate to speakers and conference participants.SOLUTION: A conference support system 1 for collecting voices of conference participants, reproducing the collected voices with speakers, and emitting the voices to the conference participants, thereby supporting the conference, includes a microphone 30 for converting input audio signals into electric signals, a filter (high-pass filter 42) for passing only electric signals corresponding to components of a predetermined frequency or higher out of the electric signals converted by the microphone 30, an amplifier 50 for amplifying the electrical signals passing through the filter (high-pass filter 42), a speaker 60 for reproducing the electrical signals amplified by the amplifier 50, and a paraboloid which is formed at a part of the ceiling and reflects voices reproduced by the speaker 60.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a conference support system that prevents a conversation in a meeting space or the like from being overheard by other nearby workers and reducing the productivity of the other workers.

In recent workplaces, a space for meetings, meetings, etc. (meeting space) may be arranged close to a space where an individual works (office space).

In addition, with the aim of inducing collaboration, the installation of open work spaces and the introduction of free desks are being promoted, where it is easy for workers to come close to each other and have conversations. Here, an open work space is a large desk that can seat several people, and is a space where each worker can freely use and work.

For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2010-4962) discloses a furniture system mainly composed of a free address type large desk that can be used by a plurality of workers facing each other.

In addition, in order to facilitate the transition from individual work to conversations and meetings, workplaces where various spaces are mixed are often planned.

However, in a workplace where various spaces are mixed, there is a problem that the productivity of other workers is reduced when conversations in meeting spaces and open work spaces can be heard by other workers nearby. there were.

Therefore, in the application of Patent Document 2 (Japanese Patent Application No. 2020-86764), the inventor collects the utterances of the conference participants, reproduces the collected utterances with a speaker, and presents them to the conference participants. In a conference support system for supporting a conference, a parabolic surface formed on a part of the ceiling is provided, and a configuration is proposed in which the sound reproduced by the speakers is reflected by the parabolic surface. In addition, in the same application, since there is a loop such as microphone → amplifier → speaker (→ parabolic ceiling surface) → microphone, and howling suppression measures are necessary, the second embodiment of the same application suppresses howling by the electroacoustic device. I proposed how to do it.
Japanese Unexamined Patent Application Publication No. 2010-4962 Japanese Patent Application No. 2020-86764

However, the above application does not specifically specify the frequency characteristics of the speaker or the like used to reproduce the sound. There was a problem that it was not described whether it was good or not.

In addition, although the same application proposed measures to suppress howling, at present, even if howling is suppressed by the above electroacoustic device, the effect is insufficient, and the amplification factor of the sound reproduced from the speaker cannot be increased. , there is a problem that the volume of conversation voices transmitted to speakers and conference participants is insufficient.

The present invention is intended to solve the above-described problems, and the conference support system according to the present invention collects the sounds of conference participants, reproduces the collected sounds with speakers, A conference support system that supports a conference by emitting sound, comprising: a microphone that converts an input audio signal into an electrical signal; an amplifier that amplifies the electrical signal that has passed through the filter; a speaker that reproduces the electrical signal amplified by the amplifier; and a part of the ceiling that reflects the sound reproduced by the speaker. and a paraboloid defined by

Further, the conference support system according to the present invention is a conference support system that collects sounds of conference participants, reproduces the collected sounds with a speaker, and emits sounds to the conference participants to support the conference, A microphone that converts an input audio signal into an electrical signal, an amplifier that amplifies the electrical signal converted by the microphone, and only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals amplified by the amplifier. and a paraboloid formed on a part of the ceiling that reflects the sound reproduced by the tweeter.

Further, the conference support system according to the present invention is a conference support system that collects sounds of conference participants, reproduces the collected sounds with a speaker, and emits sounds to the conference participants to support the conference, A microphone that converts an input audio signal into an electrical signal, a filter that passes only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals converted by the microphone, and an electrical signal that has passed through the filter An amplifier for amplification, a tweeter for reproducing only an electric signal corresponding to a component of a predetermined frequency or higher among the electric signals amplified by the amplifier, and a part of the ceiling that reflects the sound reproduced by the tweeter. and a paraboloid.

Also, the conference support system according to the present invention is characterized in that the predetermined frequency of the component corresponding to the electrical signal passed by the filter is 1 kHz or higher.

Also, the conference support system according to the present invention is characterized in that the predetermined frequency of the component corresponding to the electric signal reproduced by the tweeter is 1 kHz or higher.

Also, the conference support system according to the present invention is characterized in that a sound insulating plate is arranged below the speaker.

Since the conference support system according to the present invention has a filter that passes only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals converted by the microphone, such a conference support system according to the present invention can be used. The system can provide an indication of how the sound captured by the microphone can be amplified and reproduced to adequately convey it to speakers and conference participants.

Further, according to the conference support system according to the present invention, it is possible to increase the amplification factor of the sound reproduced from the speaker by the filter as described above, and to sufficiently increase the volume of the conversation sound transmitted to the speaker and the conference participants. can be raised.

Further, since the conference support system according to the present invention has a tweeter that reproduces only the electric signal corresponding to the component of a predetermined frequency or higher among the electric signals amplified by the amplifier, the conference support system according to the present invention has such a tweeter. According to the conference support system, it is possible to provide an indication as to how the sound recorded by the microphone should be amplified and reproduced so as to be properly transmitted to the speaker and conference participants.

Further, according to the conference support system according to the present invention, it is possible to increase the amplification factor of the voice reproduced from the tweeter as described above, and to sufficiently increase the volume of the conversation voice transmitted to the speaker and the conference participants. can be done.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the outline|summary of the meeting support system 1 which concerns on embodiment of this invention. 3 is a block diagram of the audio processing unit 40 of the conference support system 1 according to the embodiment of the invention; FIG. 4 is a diagram for explaining the geometric arrangement of speakers 60 and the ceiling in the conference support system 1; FIG. FIG. 10 is a diagram for explaining reflected sound from the parabolic ceiling part 17 of the conference support system 1; It is a block diagram of the conference support system 1 according to the second embodiment of the present invention. It is a block diagram of the meeting support system 1 which concerns on 3rd Embodiment of this invention. FIG. 12 is a block diagram of a voice processing unit 40 of the conference support system 1 according to the fourth embodiment of the present invention; It is a figure explaining the outline|summary of the meeting support system 1 which concerns on 5th Embodiment of this invention. It is a figure explaining the case where the reflector R is put in the sound emission range of sound. It is a figure explaining the outline|summary of the meeting support system 1 which concerns on 6th Embodiment of this invention. FIG. 7 is a diagram for explaining differences in propagation paths based on the height of the focal point F and the height of the sound insulating plate 70; 4 is a schematic diagram of a sound propagation path when the upper surface of the sound insulating plate 70 is flat and parallel to the floor surface 20. FIG. FIG. 10 is a diagram illustrating a problem caused by a small speaker 60 that is aligned with the focal point F; It is a figure explaining the effect of the meeting support system 1 which concerns on 6th Embodiment of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. The conference support system 1 according to the present invention is assumed to be applied to, for example, a free-address large desk where work is performed, or a meeting space provided in a place close to an open work space. It is.

In addition, it is assumed that office workers will work in the above-mentioned free address type large desks and open work spaces, and meetings will be held in meeting spaces, and conference participants will speak.

In this specification, "worker" is defined as a person who engages in paperwork and computer input work as desk work and basically does not speak, and is a conference participant who participates in a meeting and speaks in a meeting space. distinguish.

In the conference support system 1 according to the present invention, the contents of conversations by participants in the meeting space are not audible as much as possible to other workers in the large desks and open work spaces nearby, and appropriate The purpose is to emit a sound that is natural. In order to realize this, the conference support system 1 according to the present invention collects the voices of (the speakers in) the conference participants, reproduces the collected sounds with speakers, and emits the sounds to the conference participants. to support the conference.

By the way, speech is composed of vowels and consonants. The former mainly consists of low-frequency components, and the latter mainly consists of high-frequency components. In hearing, it is known that low-frequency components mask high-frequency components, and this masking also works when perceiving speech. Such masking is one of the causes of poor hearing of speech.

In the conference support system 1 according to the present invention, when the speaker's collected sound is played back to the conference participants by the speaker, attention is paid to such voice and auditory characteristics. By specifying the frequency of the sound to be played, we are trying to solve the problem by suppressing the deterioration of the clarity of the reproduced sound.

FIG. 1 is a diagram illustrating an overview of a conference support system 1 according to an embodiment of the present invention. A situation is shown in which two participants are holding a conference at a desk 25 placed on the floor surface 20 . In the vicinity of this desk 25, it is assumed that workers are working at the above-mentioned free address type large desks or open work spaces (none of which is shown).

A microphone 30 is installed on the desk 25, and the microphone 30 collects the voices of conference participants. The microphone 30 converts an audio signal into an electric signal when the audio signal is input.

An electrical signal converted by the microphone 30 is input to the audio processing section 40 . The audio processing unit 40 converts the electric signal into an appropriate signal for reproduction by the speaker 60 . FIG. 2 is a block diagram of the audio processing section 40 of the conference support system 1 according to the embodiment of the present invention. The audio processing unit 40 in FIG. 2 is one example, and various other aspects can be adopted. In the audio processing unit 40 shown in FIG. 2, the volume adjustment unit 41 adjusts the level of the electrical signal, and the amplifier 50 amplifies the electrical signal.

In FIG. 2, the electrical signal converted by the microphone 30 is input to the high-pass filter 42 in the audio processing section 40 . The high-pass filter 42 is a filter that passes only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals output from the microphone 30 . The predetermined frequency of the component corresponding to the electrical signal passed by the high-pass filter 42 is preferably 1 kHz.

Most Japanese syllables are composed of consonants and vowels, each of which has different frequency characteristics. In Japanese conversation, consonants are said to play an important role in conveying speech clearly. Therefore, in this embodiment, the high-pass filter 42 cuts the low-frequency components that make up the vowels, and emphasizes the consonants that are made up of the high-frequency components, thereby improving the ability to hear speech.

The present invention basically amplifies the component of 1 kHz or more (reproduction frequency band) among conversational sounds recorded by the microphone 30 and reproduces it from the speaker 60 installed at the focal point of the parabolic ceiling portion 17.

That is, in the present invention, by adopting a system that amplifies and reproduces the sound mainly in the reproduction frequency band, only the frequency band containing many consonant components is emphasized to reproduce the voice.

A consonant has a main component in a higher frequency band (1 kHz to 6 kHz) than a vowel, and the frequency band containing the main component of a consonant is 1 kHz to 6 kHz. Therefore, in the conference support system 1 according to the present invention, the reproduction frequency band may be 1 kHz or more and 6 kHz or less. In this case, instead of the high-pass filter 42, a band-pass filter having a pass band of 1 kHz to 6 kHz can be used.

However, in the conference support system 1 according to the present invention, the reproduction frequency band is basically set to 1 kHz or higher, and more preferably includes a band of 6 kHz or higher. This is because consonant components are also included in the frequency band above 6 kHz, although they are weaker than in the band from 1 kHz to 6 kHz. Even if the energy of a consonant is very small, it affects the intelligibility of a conversation. Therefore, it is more preferable to include 6 kHz or more in the reproduction frequency band, even though it does not contain major components.

Now, the output from the high-pass filter 42 is input to the volume adjustment section 41 . The volume adjustment unit 41 adjusts the volume of sound reproduced by the speaker 60 . This volume adjustment unit 41 may be performed automatically or manually. In the latter case, it is preferable that the input knob for volume adjustment, the input slider, and the like be appropriately provided on the desk 25 .

The electric signal amplified by the amplifier 50 of the audio processing unit 40 is input to the speaker 60, and the speaker 60 reproduces sound. The speaker 60 is installed so that the directional direction is upward, and the sound is radiated from the speaker 60 toward the ceiling 10 .

The ceiling 10 has a general ceiling portion 15 having a horizontal surface, and a parabolic ceiling portion 17 having a concave parabolic surface formed in a part of the general ceiling portion 15 . The conference support system 1 according to the present invention is laid out so that the parabolic ceiling portion 17 is arranged on the desk 25 . Moreover, it is preferable that the width of the parabolic ceiling portion 17 is such that at least the conference participants seated around the desk 25 are included in the plan view.

In this embodiment, the parabolic ceiling portion 17 is provided as a part of the ceiling 10, but the configuration corresponding to the parabolic ceiling portion 17 is provided independently of the ceiling 10. You may do so. For example, the ceiling 10 may be provided with a parasol-like structure corresponding to the parabolic ceiling 17 that is independent of the general ceiling 15 of the ceiling 10 .

The parabolic ceiling portion 17 as described above reflects the sound reproduced by the speaker 60 vertically downward. In the conference support system 1 according to the present invention, by devising the ceiling structure, sound can be emitted in a limited range (meeting space where the desk 25 is arranged) even if a general speaker is used. FIG. 3 is a diagram for explaining the geometric arrangement of the speakers 60 and the ceiling in the conference support system 1, and is a schematic diagram showing a cross section of the ceiling 10 and the floor 20 of the building.

The ceiling 10 is composed of a general ceiling portion 15 that is parallel to a general floor surface 20 and a parabolic ceiling portion 17 that is formed in a portion of the ceiling 10 . Here, the x-axis is the horizontal direction, the y-axis is the vertical direction, and coordinates (x, y) are defined with the arrangement position F of the speaker 60 (not shown in FIG. 3) as the origin.

At the coordinates defined above, the parabolic ceiling 17 is configured to overlap the surface of a body of revolution rotated about the y-axis by y=-x ² /4L+L. At this time, the origin (0, 0) of the xy coordinates coincides with the focal point of the parabolic ceiling portion 17 .

Also, if the directional range of the speaker 60 (not shown in FIG. 1) is φ, it is preferable that the cone of φ is within the parabolic ceiling portion 17 .

As the reproduced sound emitting means in the conference support system 1 according to the present invention, the paraboloidal ceiling portion 17 having a shape forming a part of the parabolic surface as described above and the parabolic ceiling portion 17 having a directivity direction below the paraboloidal ceiling portion 17 are provided. It is composed of a speaker 60 installed upward. Also, the speaker 60 is installed so as to be positioned at the focal point F of the paraboloid of the ceiling 10 .

In the above relationship, when the speaker 60 is arranged at F, as shown in FIG. 4, the sound reflected by the parabolic ceiling portion 17 travels vertically downward in the direction of the floor surface 20 .

In the conference support system 1 according to the present invention, the range in which the ceiling surface forms the parabolic surface is the range where the sound emitted from the speaker 60 is incident, that is, the range that can cover the directional range of the speaker 60. preferable.

The sound radiated from the speaker 60 installed at the focal point F of the paraboloid forming the paraboloid ceiling 17 enters the paraboloid ceiling 17 forming a part of the paraboloid, and then reaches the conference participants. reflects vertically downward toward the desks 25 seated around it. In the conference support system 1 according to the present invention, the sound radiated from the speaker can be contained within the desired sound emission range without using an expensive speaker system such as a parametric speaker or a flat panel speaker. Thus, the conference support system 1 according to the present invention can be realized at low cost using general speakers.

Note that the mechanism itself for supporting voice transmission by the parabolic ceiling portion 17 and the speaker 60 has already been proposed by the inventors in Japanese Patent Application No. 2017-160105 (see Japanese Unexamined Patent Application Publication No. 2019-39166). This proposal had the effect of providing sound information by BGM and announcements only in a limited range in art galleries, museums, and the like.

On the other hand, in the conference support system 1 according to the present invention, the participants of the conference listen to their own voices reproduced by the speakers 60 and reflected by the parabolic ceiling portion 17, thereby objectively judging their own voice volume. can be considered to be possible. Therefore, conference participants come to control and suppress their own voice volume by themselves. As a result, the conference support system 1 can suppress conversations at a volume that is audible to workers who are close to the meeting space. Such an effect cannot necessarily be easily derived from the previous proposal.

Now, if the parabolic ceiling portion 17 is wider than the main directivity range of the speaker 60, the reproduced sound from the speaker 60 is emitted only directly below the parabolic ceiling portion 17 without propagating to the surroundings.

In this way, if the directivity range of the parabolic ceiling part 17 and the speaker 60 is appropriately set so as to cover the meeting space, the sound recorded by the microphone 30 will be transmitted to the meeting participants who are having a conversation in the meeting space. is reliably transmitted only to

A feature of voice transmission support by the conference support system 1 according to the present invention is that the speaker's own conversation voice is amplified and transmitted not only to the other party of the conversation but also to the speaker himself/herself.

By using the conference support system 1 according to the present invention, the speaker can hear his/her own voice loudly and feel that his/her own voice is surely transmitted to the other party of the conversation. can be expected to adjust to In this way, if the volume of the speaker's voice is suppressed, the conversational voice that propagates from the meeting space to the surroundings is reduced, reducing the work efficiency of other nearby workers and reducing the degree of interference with other conversations. be able to.

In this way, it is possible to reliably transmit the voice to the conference participants who are conversing only in the meeting space covered by the parabolic ceiling portion 17, and to guide the speaker in the direction of suppressing the volume of the conversation. can. As a result, it is possible to reduce the decrease in work efficiency of other nearby workers and the degree of interference with other conversations.

Preferably, the microphone 30 used in the conference support system 1 according to the present invention is installed on the desk 25 . However, it is also possible to use a pin microphone worn by each of the conference participants who are having a conversation.

According to the conference support system 1 according to the present invention configured as described above, the conversation in the meeting space can be heard by other workers in the vicinity without taking measures such as enclosing the meeting space with partitions. , it is possible to suppress the decrease in the productivity of the other worker.

Since the conference support system 1 according to the present invention has the high-pass filter 42 that passes only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals converted by the microphone 30, such According to the conference support system 1 according to the present invention, it is possible to provide an index as to how the sound recorded by the microphone 30 should be amplified and reproduced so that it can be properly transmitted to the speaker and conference participants. Become.

Further, according to the conference support system 1 according to the present invention, by providing the high-pass filter 42 as described above, it becomes possible to increase the amplification factor of the sound reproduced from the speaker 60, and the sound is transmitted to the speaker and the conference participants. You can raise the volume of the conversation voice to be sufficiently high.

Conversely, since the reproduction based on the reproduction frequency band makes the conversation sound clearer, the effect that the sound can be appropriately transmitted to the conference participants can be obtained without increasing the amplification factor of the reproduced sound. Obtainable. That is, even if the amplification factor is such that howling does not occur, it is possible to appropriately transmit the voice to the conference participants.

Further, according to the conference support system 1 according to the present invention, when the howling frequency is outside the reproduction frequency band, it is possible to sufficiently increase the amplification factor, thereby improving the voice transmission to the conference participants. can be improved.

Further, according to the conference support system 1 according to the present invention, the range covered by the paraboloid on the ceiling is limited, and the voice is reliably transmitted only to the participants of the conference, while suppressing the conversation volume of the speaker. It can be guided in the direction to do.

As a result, it becomes possible to reduce the conversational voice that propagates to adjacent spaces. In addition, as a result, it is possible to reduce the degree of deterioration in the work efficiency of other workers working in the adjacent space, reduce the degree of interference with other conversations held in the adjacent space, and reduce the noise of the entire workplace. The effect of being able to reduce is obtained.

In addition, according to the conference support system 1 of the present invention, when having a highly confidential conversation in a meeting space, it is possible to prevent the content of the conversation from leaking out to the surroundings.

In addition, in the conference support system 1 according to the present invention, if a microphone installed on a desk is used, a wearable device such as an intercom is unnecessary, and the above effect can be obtained without impairing convenience. Wearing an intercom or the like impairs convenience, and it may lead to a decrease in the efficiency of meetings due to discomfort for workers other than those who are accustomed to it.

Further, in the conference support system 1 according to the present invention, a general speaker can be used as the speaker installed at the focal point, and the above effect can be realized at low cost. Parametric speakers and flat panel speakers exist as speaker systems having narrow directional characteristics in order to reproduce speech sounds in a limited range, but there are problems in price and sound quality.

Further, the conference support system 1 according to the present invention is effective not only when actually having a face-to-face conversation, but also when having a conversation with a remote party such as a web conference.

Next, another embodiment of the present invention will be described. In the previous embodiment, the high-pass filter 42 passes only electrical signals corresponding to components of a predetermined frequency or higher out of the electrical signals output from the microphone 30 and reproduces them from the speaker 60. On the other hand, in the second embodiment, by replacing the speaker 60 with a tweeter 67 without using such a filter, components above a predetermined frequency are reproduced. Other configurations are similar to those of the first embodiment. FIG. 5 is a block diagram of such a conference support system 1 according to the second embodiment of the present invention. As in the previous embodiment, also in the second embodiment, the sound reproduced by the tweeter 67 is reflected by the parabolic ceiling section 17 formed in a part of the ceiling.

In this specification, the tweeter 67 is defined as a speaker that reproduces sound components of 1 kHz or more and does not reproduce sound components of less than 1 kHz. That is, the frequency of the sound component corresponding to the electric signal reproduced by the tweeter 67 of FIG. 5 is 1 kHz or higher, and the electric signal corresponding to the sound of a frequency lower than that is not reproduced.

In the conference support system 1 according to the second embodiment, the volume adjustment unit 41 adjusts the level of the electric signal of the conversation voice recorded by the microphone 30, and the amplifier 50 amplifies the electric signal. Of the conversational voice, basically only components of 1 kHz or more (reproduction frequency band) are reproduced by the tweeter 67 installed at the focal point of the parabolic ceiling portion 17 . That is, in the second embodiment, the tweeter 67 amplifies and reproduces the sound mainly in the reproduction frequency band, thereby emphasizing only the frequency band containing many consonant components and reproducing the sound. According to such a second embodiment, it is possible to enjoy the same effects as those of the previous embodiment.

Next, another embodiment of the present invention will be described. FIG. 6 is a block diagram of the conference support system 1 according to the third embodiment of the invention. In the conference support system 1 according to the third embodiment,
The audio processing unit 40 employs a high-pass filter 42 that passes only electrical signals corresponding to sound components of 1 kHz or higher. After passing through the high-pass filter 42 , the electrical signal level is adjusted by the volume control section 41 , and the electrical signal is amplified by the amplifier 50 . The electric signal amplified by the amplifier 50 is input to a tweeter 67 that reproduces sound components of 1 kHz or higher.

As described above, in the conference support system 1 according to the third embodiment, both the high-pass filter 42 and the tweeter 67 are used, and the same effects as those of the previous embodiment can be obtained by such an embodiment. .

Next, another embodiment of the present invention will be described. In the embodiments described so far, a high-pass filter and a tweeter are used to reproduce only electrical signals corresponding to sound components of a predetermined frequency or higher (preferably 1 kHz or higher). On the other hand, in the fourth embodiment, if necessary, the sound below a predetermined frequency is cut and the component of 1 kHz or more (reproduction frequency band) is reflected by the parabolic ceiling part 17, so that the participants can participate in the conference. It is structured so that people can listen to it. FIG. 7 is a block diagram of the audio processor 40 of the conference support system 1 according to the fourth embodiment of the invention.

In FIG. 7, the electrical signal converted by the microphone 30 is input to the high-pass filter 42, and the high-pass filter 42 filters out only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals output from the microphone 30. let it pass. The electrical signal converted by the microphone 30 is also input to the low-pass filter 43, and the low-pass filter 43 passes only electrical signals corresponding to components below a predetermined frequency among the electrical signals output from the microphone 30.

A variable gain amplifier 44 is provided on the line on which the high-pass filter 42 is provided, and is set so that a gain greater than at least 1 is obtained. On the other hand, an opening/closing switch 45 is arranged on the line where the low-pass filter 43 is provided, and this opening/closing switch 45 is provided near the desk 25 which can be operated by the participants of the conference. Also, the gain of the variable gain amplifier 44 is configured to be changeable by an adjustment section (not shown). It is preferable that the adjustment section is also provided near the desk 25 and configured so that the conference participants can operate and adjust it.

The line output from the high-pass filter 42 and the line output from the low-pass filter 43 are added and input to the volume adjustment section 41 . The volume adjuster 41 adjusts the level of the electric signal, and the amplifier 50 amplifies the electric signal. The electric signal amplified by the amplifier 50 is input to the speaker 60, and sound is reproduced from the speaker 60 toward the parabolic ceiling portion 17 as in the embodiments described so far.

An opening/closing switch 45 is provided on the line on the low-pass filter 43 side, but even if the opening/closing switch 45 on the line on the low-pass filter 43 side is closed, the variable gain amplifier 44 is not connected to the line on the high-pass filter 42 side. Therefore, the level of the electrical signal that is added to the volume control section 41 and is input to the volume control section 41 is higher in the line on the side of the high-pass filter 42 . Therefore, in the sound components reproduced by the speaker 60, components of a predetermined frequency or higher (for example, 1 kHz or higher) are emphasized. As a result, in the conference support system 1 according to the fourth embodiment as well, since the sound is reproduced in which the frequency band basically containing many consonant components is emphasized, the sound can be easily heard.

On the other hand, in order to further improve the audibility of the conference participants, the open/close switch 45 can be opened to completely cut off sound components below a predetermined frequency. When the open/close switch 45 for the line on the low-pass filter 43 side is opened, the electrical signal input to the volume control unit 41 is only output from the line on the high-pass filter 42 side. Thus, according to the conference support system 1 according to the fourth embodiment, it is possible to obtain the same effects as those of the previous embodiment.

Next, another embodiment of the present invention will be described. In the embodiments described so far, since the microphone 30 exists in the sound emission range (presentation range) of the speaker 60 and the parabolic ceiling portion 17, sound input to the microphone 30→amplification by the amplifier 50→speaker Howling is expected to occur due to a loop of playback from 60→input of sound to microphone 30. FIG. Therefore, in the fifth embodiment, a configuration for suppressing such howling is adopted.

FIG. 8 is a diagram for explaining the outline of the conference support system 1 according to the fifth embodiment of the present invention. The conference support system 1 according to the fifth embodiment can be arbitrarily combined with any of the first to fourth embodiments described above.

In FIG. 8, as a configuration for suppressing howling, a sound insulating plate 70 provided below the speaker 60, a cover body 80 provided above the microphone 30, and a truncated cone or truncated quadrangular pyramid for placing the microphone 30 are provided. Four configurations of the microphone stand 27 formed and the sound absorbing material 90 laid on the desk 25 are shown.

In the present embodiment, each configuration may be used alone or may be used in arbitrary combination for howling suppression.

The sound insulating plate 70 is provided to prevent the sound reflected by the parabolic ceiling portion 17 from being collected again by the microphone 30 . It is preferable that the arrangement relationship is such that the sound insulating plate 70 and the microphone 30 overlap each other in plan view.

In addition, by providing the cover body 80 above the microphone 30, the microphone 30 is prevented from collecting sound from above the microphone 30, so that the sound mainly from the conference participants is collected.

The shape of the microphone base 27 on which the microphone 30 is placed is a truncated cone or a truncated quadrangular pyramid. is suppressed from picking up sound from the lower side.

Also, the sound absorbing material 90 laid on the desk 25 absorbs sound incident from above, thereby suppressing the sound reflected by the desk 25 from being picked up by the microphone 30 from below.

In the configuration as described above, among conversational voices recorded by the microphone 30, components of 1 kHz or higher (reproduction frequency band) are basically amplified and reproduced from the speaker 60 installed at the focal point of the parabolic ceiling portion 17. . Furthermore, in the conference support system 1 according to the fifth embodiment, each physical howling suppression measure as described above is taken, and even when the howling frequency is within the reproduction frequency band, the sound insulation plate Since the diffraction effect by 70 or the sound absorbing effect by the cover body 80 and the sound absorbing material 90 is high, the amplification factor can be sufficiently increased, and the hearing of the sound can be improved. Moreover, according to the fifth embodiment, the same effects as those of the previous embodiment can be obtained.

Next, a sixth embodiment of the present invention will be described. The conference support system 1 according to the sixth embodiment can be used in arbitrary combination with any of the first to fourth embodiments described above.

In the conference support system 1 according to the present invention, the sound radiated from the speaker 60 installed upward at the focal point F of the parabolic ceiling portion 17 is reflected vertically downward by the parabolic ceiling portion 17, It is characterized in that sound is emitted only within the range covered by the surface ceiling portion 17 .

In the conference support system 1 according to the present invention, as shown in FIG. 9, a reflector R is placed in the range where sound is emitted (the area below the parabolic ceiling 17 in plan view). In this case, the sound reflected by the parabolic ceiling portion 17 is reflected or scattered by these reflectors R, and the sound propagates outside the range covered by the parabolic ceiling portion 17 where the sound is originally intended to be emitted. There is a problem that Here, in FIG. 9, the configuration of the microphone 30 and the like is omitted from illustration. Examples of the reflector R include displays, personal computers, bookshelves, and desk lights.

As for the desk 25, since the top surface of the desk 25 is generally flat and parallel to the floor surface 20, the sound reflected on the top surface of the top plate after being reflected by the paraboloid ceiling portion 17 is reflected in the direction of the paraboloid ceiling portion 17. , and the sound is not propagated outside the desired sound emission range, so it is not considered as a reflector R here.

In order to solve the above problems, in the conference support system 1 according to the sixth embodiment, the sound insulation plate 70 is arranged flush with the horizontal plane including the uppermost end of the configuration including the housing 61 of the speaker 60. I am trying to FIG. 10 is a diagram for explaining the outline of the conference support system 1 according to the sixth embodiment of the present invention.

The speaker 60 is composed of a magnet coil portion 62 that serves as a vibration source, and a cone portion 65 that substantially serves as a vibrating portion as a sound source by being vibrated by this vibration source. moreover,
However, the horizontal plane including the top end of the cone portion 65 and the upper surface of the sound insulating plate 70 are laid out so as to be flush with each other. The reason for such a layout will be described later.

In general, the speaker 60 itself is not used alone, but is used while being housed in a housing 61 such as an enclosure. The top surface of the sound insulating plate 70 is laid out so as to be flush with the horizontal plane including the top end of the housing 61 . The reason for such a layout will be described later.

Note that the housing 61 does not include a metal mesh or the like installed in front of the cone portion 65 of the speaker 60 in order to protect the cone portion 65 . This is because such a protective material such as a metal mesh can be regarded as acoustically transparent. Further, the housing 61 does not include minute protrusions such as screws and screws.

The installation range of the sound insulating plate 70 is set so that it overlaps with or exceeds the reflecting object R in terms of the positional relationship in plan view, and the reflecting object R is included in the range of the sound insulating plate 70. - 特許庁However, in a plan view, the range of the sound insulating plate 70 is narrower than that of the parabolic ceiling portion 17, and the range does not overlap with the conference participants to whom the sound is to be emitted.

The material and structure of the sound insulation plate 70 should have a certain level of sound insulation performance (for example, a sound transmission loss of 10 dB or more is desirable) with respect to the frequency component of the sound to be emitted. In the embodiment shown in FIG. 10, the shape of the sound insulating plate 70 is circular in plan view, but the planar shape of the sound insulating plate 70 is not particularly limited to this, and the sound insulating plate 70 is square in plan view. , polygonal, irregular, etc.

The cross-sectional shape of the sound insulating plate 70 is such that at least the upper surface thereof is flat and parallel to the floor surface 20 . However, in this case, the general ceiling part 15 is parallel to the floor surface 20, and the parabolic ceiling part 17 is installed so that the sound emitted from the speaker 60 is reflected perpendicularly to the floor surface 20. It is based on the premise that

In the conference support system 1 according to the sixth embodiment, the layout is such that the sound insulating plate 70 is flush with the horizontal plane including the uppermost end of the configuration including the housing 61 of the speaker 60. This layout is as follows. for some reason.

11A and 11B are diagrams for explaining differences in propagation paths based on the height of the focal point F and the height of the sound insulating plate 70. FIG. FIG. 11B is a schematic diagram of the sound propagation path when the upper surface of the sound insulating plate 70 is installed at the same height as the focal point.

As shown in FIG. 11A, when the upper surface of the sound insulating plate 70 is installed below the speaker 60, that is, the focal point F, the sound that goes downward from the speaker is reflected on the upper surface of the sound insulating plate 70, and then the parabolic surface is formed. Incident on the ceiling part 17 . At this time, the direction of incidence coincides with the direction of incidence of sound radiated from the virtual image F' of the focal point, which is positioned symmetrically with respect to the upper surface of the sound insulating plate 70 as the plane of symmetry. For this reason, the reflection direction of the sound incident on the parabolic ceiling portion 17 is not vertically downward with respect to the floor surface 20, and the sound is reflected outside the range covered by the parabolic ceiling portion 17 where the sound is desired to be emitted. propagate.

On the other hand, as shown in FIG. 11B, if the upper surface of the sound insulating plate 70 is at the same height as the uppermost end of the housing 61 in which the speaker 60 is housed, the virtual image of the focal point is at the same position as the real image (original focal point). , so this problem does not occur. For this reason, in the conference support system 1 according to the sixth embodiment, the upper surface side of the sound insulating plate 70 is installed at the same height as the uppermost end of the housing 61 of the speaker 60 . It should be noted that this installation substantially corresponds to disposing the sound insulating plate 70 whose upper surface is flush with the horizontal surface including the uppermost end of the housing 61 in which the speaker 60 is housed. .

The reason why the upper surface of the sound insulating plate 70 is flat and parallel to the floor surface 20 (that is, the horizontal surface) in the conference support system 1 according to the sixth embodiment is as follows. FIG. 12 is a schematic diagram of a sound propagation path when the upper surface of the sound insulating plate 70 is flat and parallel to the floor surface 20. As shown in FIG.

Sound (1) radiated from the speaker 60 installed at the focal point F is incident on the parabolic ceiling portion 17 and then reflected vertically downward (2). The sound reflected vertically downward from the parabolic ceiling portion 17 is incident on the upper surface of the sound insulating plate 70. At this time, if the upper surface of the sound insulating plate 70 is flat and parallel to the floor surface, the sound insulating plate 70 The sound incident on the upper surface is reflected vertically upward (3), and then reflected again from the parabolic ceiling portion 17 toward the focal point F (4).

After that, reflection is repeated in the order of focal point F of speaker 60→parabolic ceiling portion 17→top surface of sound insulating plate 70→parabolic ceiling portion 17→focal point F of speaker 60→ . . . The sound never propagates outside the desired sound emission range covered by . For this reason, the upper surface of the sound insulating plate 70 is flat and parallel to the floor surface 20 .

Next, a speaker 60 that can be used in the conference support system 1 according to the sixth embodiment of the present invention will be described. According to the technology proposed by the present invention, it is required to install the speaker 60 at the focal point F of the parabolic ceiling portion 17, and in order to install the speaker 60 at the focal point accurately, it is desirable that the speaker 60 is small. However, in general, a small speaker 60 has a wide directional range in a wide frequency band, and as shown in FIG. However, there is a problem that the sound propagates directly to the outside of the range in which the sound is originally desired to be emitted.

By installing the sound insulation plate 70 according to the conference support system 1 according to the sixth embodiment, as shown in FIG. It is also possible to obtain the effect of reducing the wraparound of sound. As a result, it is possible to more reliably emit sound limited to the range covered by the parabolic ceiling portion 17 .

If the sound insulating plate 70 as in the sixth embodiment is used, there is no need to custom-manufacture a speaker in which a small speaker unit is attached to a large housing in order to obtain the above effects. The above effects can be obtained by constructing a system using small speakers that are generally available on the market.

In the configuration as described above, among conversational voices recorded by the microphone 30, components of 1 kHz or higher (reproduction frequency band) are basically amplified and reproduced from the speaker 60 installed at the focal point of the parabolic ceiling portion 17. . Furthermore, according to the conference support system 1 according to the sixth embodiment configured as described above, the sound reflected by the parabolic ceiling portion 17 propagates to the area below the sound insulating plate 70 in plan view. can be prevented. As a result, it is possible to prevent the sound from propagating beyond the range where the sound is originally desired to be emitted by being reflected or scattered by the reflector R such as the display located under the parabolic ceiling.

Further, in the conference support system 1 according to the sixth embodiment, even when the howling frequency is within the reproduction frequency band, the diffraction effect of the sound insulation plate 70 is high in the high frequency range, so the amplification factor can be sufficiently increased. It is possible to improve speech comprehension.

Moreover, according to the fifth embodiment, the same effects as those of the previous embodiment can be obtained.

As described above, according to the conference support system according to the present invention, it is possible to provide an index as to how the voice recorded by the microphone should be amplified and reproduced so that it can be properly transmitted to the speaker and the conference participants. Become.

Further, according to the conference support system of the present invention, it is possible to increase the amplification factor of the sound reproduced from the speaker, and to sufficiently increase the volume of the conversational sound transmitted to the speaker and the conference participants.

Further, according to the present invention, since it is possible to prevent the sound from propagating beyond the range in which the sound is desired to be emitted, as an effect of this, sound information such as BGM and announcements is limited to the range covered by the parabolic ceiling portion 17. It is possible to more reliably provide

Further, according to the present invention, the range covered by the parabolic ceiling portion 17 is limited, and the voice is reliably transmitted only to the conference participants who are having a conversation, while suppressing the volume of the conversation voice of the speaker. , thereby more reliably reducing conversational sound propagating to adjacent spaces. As a result, it reduces the degree of deterioration in the work efficiency of other workers working in the adjacent space, reduces the degree of interference with other conversations held in the adjacent space, and reduces the noise of the entire workplace. The effect of being able to do so can be obtained more reliably.

Moreover, according to the present invention, when a conversation with high confidentiality is held in a meeting space, it is possible to make it more difficult to leak the content of the conversation to the surroundings.

Reference Signs List 1 Conference support system 10 Ceiling 15 General ceiling 17 Parabolic ceiling 20 Floor 25 Desk 27 Microphone stand 30 Microphone 40 Audio processing unit 41 Adjustment unit 42 High pass filter 43 Low pass filter 44 Variable gain amplifier 45 Open/close switch 50 Amplifier 60 Speaker 61 Housing 62 Magnet coil portion 65 Cone portion 67 Tweeter 70 Sound insulating plate 80 Cover body 90 Sound absorbing material R Reflective object

Claims (6)

In a conference support system that collects the voices of conference participants, reproduces the collected sounds with speakers, and emits the sounds to the conference participants to support the conference,
a microphone that converts an input audio signal into an electrical signal;
a filter that passes only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals converted by the microphone;
an amplifier that amplifies the electrical signal that has passed through the filter;
a speaker that reproduces the electrical signal amplified by the amplifier;
and a paraboloid formed on a part of a ceiling that reflects sound reproduced by the speaker. In a conference support system that collects the voices of conference participants, reproduces the collected sounds with speakers, and emits the sounds to the conference participants to support the conference,
a microphone that converts an input audio signal into an electrical signal;
an amplifier that amplifies the electrical signal converted by the microphone;
a tweeter that reproduces only an electrical signal corresponding to a component of a predetermined frequency or higher among the electrical signals amplified by the amplifier;
and a paraboloid formed on a part of a ceiling that reflects sound reproduced by the tweeter. In a conference support system that collects the voices of conference participants, reproduces the collected sounds with speakers, and emits the sounds to the conference participants to support the conference,
a microphone that converts an input audio signal into an electrical signal;
a filter that passes only electrical signals corresponding to components of a predetermined frequency or higher among the electrical signals converted by the microphone;
an amplifier that amplifies the electrical signal that has passed through the filter;
a tweeter that reproduces only an electrical signal corresponding to a component of a predetermined frequency or higher among the electrical signals amplified by the amplifier;
and a paraboloid formed on a part of a ceiling that reflects sound reproduced by the tweeter. 4. The conference support system according to claim 1, wherein the predetermined frequency of the component corresponding to the electrical signal passed by the filter is 1 kHz or higher. 4. The conference support system according to claim 2, wherein the predetermined frequency of the component corresponding to the electric signal reproduced by the tweeter is 1 kHz or higher. 6. The conference support system according to any one of claims 1 to 5, wherein a sound insulating plate is arranged below the speaker.

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