JP2665007B2 - Super directional speaker system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a super directional speaker applied to a broadcasting facility such as an exhibition hall or an entertainment facility.

[Prior art] Japanese Patent Laid-Open No. 60-1985 describes a parametric speaker.
A mechanism for reducing ultrasonic waves is proposed in 167597, etc., but a technique that uses ultrasonic waves emitted from a parametric speaker together with sound and uses reflected waves of ultrasonic waves from an object or human is proposed. It has not been.
FIG. 7 shows a configuration of a conventional parametric speaker. The sound of a sound source 30 is amplified by an amplifier 31 and is emitted as superdirective speakers 32 and 34. Reflector 33 from viewer 19
Remains unprocessed at all.

[Problems to be solved by the invention]

As described above, there is no technique using an ultrasonic wave which is generated together with the audible frequency and cannot be eliminated in the parametric speaker. Whether a viewer or the like exists in the audible range in front of the super-directional speaker is identified by detecting a reflected wave of the ultrasonic wave from the viewer or the like, and the super-directional speaker is determined according to the presence or absence of the viewer. If you can change the action (for example, sound source switching and operation), you can listen to the sound from the speaker at a volume that is easy for the viewer to hear, or play the necessary information only when the viewer is present , Etc. can be switched, but development of such technology has been desired so far. The present invention has been made to solve such a problem.

[Means for solving the problem]

In order to solve such a problem, the present invention disposes an ultrasonic receiver (sensor) around a surface on which a sounding body of a super-directional speaker is installed, and generates an ultrasonic wave emitted from the super-directional speaker. Of the sound containing the sound, the signal of the ultrasonic wave reflected from an object such as a viewer in front is received, and the control device for processing the received signal and controlling the sound source of the component of the super-directional speaker is provided. It is a speaker with additional functions.

That is, the present invention provides a super-directional speaker system comprising a super-directional speaker using a parametric array and a circuit for amplitude-modulating or amplifying an input signal from a sound source and outputting an output signal. Device that receives ultrasonic waves that are transmitted together with sound from directional speakers and that are reflected from viewers in front of the super-directional speakers, and controls the switching of sound sources by processing the received ultrasonic signals And a super directional speaker system comprising:

[Action]

The sound emitted from the super directional speaker includes sound waves in the ultrasonic wave (about 40 KHz) region in addition to sound in the audible range (up to about 20 KHz), and the sound pressure level in the frequency range of the ultrasonic wave region is lower than that in the audible range. Are known to have comparable levels.
Since the sound emitted from the super-directional speaker necessarily includes the ultrasonic wave, it is possible to use the ultrasonic wave while the sound is being emitted.

According to the present invention, the ultrasonic wave is reflected when a viewer is present in front of the super-directional speaker, is received by the ultrasonic receiver in front of the speaker, and detects a signal of a certain level.
By judging that the viewer is in front of the speaker, the sound source can be switched so that appropriate information is played.

〔Example〕

FIG. 1 is a front view of a super-directional speaker system according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. In both figures, the super-directional speaker 1 is constituted by a set of sounding bodies 2 and is supported by a support 3 and a support 4. The supporting bracket 3 is provided around the super-directional speaker 1, and an appropriate number of ultrasonic receivers 5 (4 in the embodiment of FIG. 1).
Pcs) are installed. The sounding body 2 is attached to the control board 6 of the super-directional speaker 1, and reproduces and emits an audio signal transmitted from an audio signal line 8 via an audio signal connector 7. The superdirective (strong directivity) sound signal emitted from the sounding body 2 includes sound in an ultrasonic range (for example, 40 KHz) other than human audible range sound, and is directed toward the front of the superdirective speaker 1. It is transmitted at the same time as the audible sound. The ultrasonic wave receiver 5 receives a part of the transmitted reflected wave of the ultrasonic wave, and transmits it to the ultrasonic signal processor 10 (shown in FIG. 3) via the reception signal line 9.

The ultrasonic signal processor 10 converts the received signal level and transmits a received ultrasonic signal to the controller 11. Third
FIG. 1 is a block diagram showing the configuration of the present embodiment, which is a device configuration necessary for driving superdirective speaker 1. Sound source (A) 12 and sound source (B) 13 using cassette tape, etc.
The audio signal generated from the input signal switching unit 14 is changed by the switching signal 17 by the controller 11 using a microcomputer.
The sound signal of one of the sound sources is changed by the signal modulation circuit
The signal is modulated by 15, amplified by the power amplifier 16, and emitted from the super-directional speaker 1 via the audio signal line 8.

In FIG. 4, the sound signal including the ultrasonic waves 18 emitted from the super-directional speaker 1 is transmitted with strong directivity toward the front of the sounding body 2 by the action of the sounding body 2. When a viewer 19 is present in front of the super-directional speaker 1, only the reflected ultrasonic wave 20 of the audio signal including the ultrasonic wave 18 reflected by the viewer 19 is an ultrasonic wave splitter. It is received by the device 5 and processed by the control unit 23. Here, 21 is an amplifier section of the super-directional speaker, and 22 is a sound source section.

FIG. 5 is a waveform diagram of a signal received by the ultrasonic receiver 5 and transmitted to the controller 11. The vertical axis of the received signal of the reflected wave 20 processed by the ultrasonic signal processor 10 and transmitted to the controller 11 is shown in FIG. FIG. 5 is a diagram showing a reception signal level and time on the horizontal axis. Audience
In the period (TA) when the signal 19 does not exist in front of the front of the super-directional speaker 1 and in the period (TB), the received signal level is large in the latter case. Received signal level threshold (Pm
in) is a received signal level of an arbitrary value used for determining whether or not the reflected wave 20 from the viewer 19 exists.

FIG. 6 is a flowchart of the processing performed by the controller 11 for the microcomputer. In the step, sound source (A)
12 is switched by an input signal switch 14 and used as an input sound source of the signal modulation circuit 15 to be sounded by the super-directive speaker 1. In the step, a threshold value (Pm) detected at an arbitrary time interval (Δt)
in) Initialize the number of occurrences (n) of the received signal level above. In the step, the ultrasonic reception signal (p), that is, the reception signal level of the reflected wave 20 sent from the ultrasonic signal processor 10 is input, and in the step, it is compared with a threshold value (Pmin). If it is, the number of occurrences (n) of the received signal level is counted up in the step, and if the comparison result is false, the process returns to the step. In the next step, the minimum number of occurrences of the received signal level (n min) is set to an arbitrary value, and is compared with (n). If the determination result is false, the process returns to the step after waiting for an arbitrary time interval (Δt) in the step. If the determination result is true, the input signal switch 14 is operated to switch from the sound source (A) 12 to the sound source (B) 13 in a step, and the sound source (B) 13 is sounded from the superdirective speaker 1.

In the same manner as in the step (1), the ultrasonic receiving signal (P) is input again, and the signal is compared with the threshold value (Pmin) in the step. If the comparison result is true, the process returns to the step. Waiting for Δt time at the step and returning to the viewer
When the sound source 19 exists only for a short time such as crossing the front of the super-directional speaker 1 or the like, the sound source (A) 12 is prevented from being switched to the sound source (B) 13 in a stepwise manner (△ t × For example, the background music (BGM) of the sound source (A) 12 is stepped only while the viewer 19 is in front of the front of the super directional speaker 1 for more than n min) time.
Is switched to, for example, the input of a specific guide broadcast of the sound source (B) 13 so that the necessary information of the viewer 19 is transmitted to the super directional speaker 1.
Be able to pronounce more.

As described above, the presence or absence of the viewer 19 is detected, and the sound emitted from the super-directional speaker 1 is automatically switched and broadcast.

Examples of the use of the super-directional speaker system of the present invention are as follows: (1) In a guide broadcast at a department store, a station or an exhibition hall, etc., usually only signals of BGM or ultrasonic waves (about 40 KHz) are used. It can be used for a system that switches to event guidance by catching viewers, and (2) catching the presence of a blind person in blind person guidance and switching to broadcasting of advance guidance in the same way as (1) above There are such systems.

〔The invention's effect〕

According to the superdirective speaker system of the present invention described above, the ultrasonic wave generated simultaneously with the sound in the audible range by the superdirective speaker is used as a signal generation source, and the apparatus is used without an ultrasonic generation circuit. Utilizing the strong directivity characteristics of the super-directional speaker and determining the presence or absence of a viewer in front of the super-directional speaker using ultrasonic waves, the super-directional speaker can be configured according to the presence or absence of the viewer. Is automatically switched, and a broadcast according to the situation can be selected.

[Brief description of the drawings]

FIG. 1 is a front view of a super directional speaker system according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line II-II in FIG.
FIG. 4 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention.
FIG. 5 is an explanatory diagram showing the operation of the embodiment of the present invention. FIG. 5 is a signal waveform diagram showing an example of a reception signal of the ultrasonic wave receiver according to the present embodiment. FIG. 7 is a flowchart showing the operation of the conventional super-directional speaker system. 1 ... super-directional speaker, 2 ... sounding body, 5 ... ultrasonic receiver, 10 ... ultrasonic signal processor, 11 ... controller, 12 ... sound source (A), 13 ... sound source (B), 14 …… Input signal switch, 15
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Reflected wave, 21... Amplifier section, 22... Sound source section, 23... Control section.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-123389 (JP, A) JP-A-60-150399 (JP, A) JP-A-60-167597 (JP, A) JP-A Sho 57- 208482 (JP, A) JP-A-57-108776 (JP, A) JP-A-64-54176 (JP, U)

Claims (1)

(57) [Claims] 1. A super-directional speaker system comprising a super-directional speaker using a parametric array and a circuit for amplitude-modulating or amplifying an input signal from a sound source and outputting an output signal. A receiving device that receives ultrasonic waves transmitted from a speaker together with sound reflected from a viewer or the like in front of a super-directional speaker, and controls switching of a sound source by processing a signal of the received ultrasonic waves. A super directional speaker system comprising a device.