JPH05327623A - Infrared ray transmission and reception system - Google Patents

Abstract

PURPOSE:To provide a infrared ray transmission reception system in which no beat interference takes place. CONSTITUTION:In the system in which a voice signal is sent from a transmission unit (microphone 10) to a relay unit in terms of an infrared ray signal and the relay unit applies the infrared ray signal to the reception unit (headphone 40), a light interrupt means (33d) is provided to one or both of a light receiving means 21 and a light emitting means 33 in the relay unit or the directivity of them is controlled to prevent the input of an infrared ray output from the light emitting means 33 to the light receiving means 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared transmission / reception system used for a microphone system, a headphone system and the like.

[0002]

2. Description of the Related Art A voice transmission / reception system using infrared rays is implemented as shown in FIGS. Figure 1
Reference numeral 5 (a) is for transmitting a microphone input voice by an infrared signal (a so-called cordless microphone system), and the microphone 10 has a sound collecting unit 11 and
A transmission modulation unit 12 that FM-modulates a carrier signal of 3.2 MHz or 3.7 MHz, for example, by a picked-up audio signal, and a light-emitting unit 13 that drives an LED (light-emitting diode) by the FM-modulated signal and outputs an infrared signal. It is provided.

On the other hand, the receiving device 20 for the microphone 10 is, for example, a light receiving portion 21 which receives an infrared signal by a light receiving element such as a photodiode and converts it into an electric signal, and a signal detected by the light receiving portion 21. To F
A reception demodulation unit 22 that demodulates M into an original audio signal and an output terminal 23 are provided. Then, by connecting the output terminal 23 of the receiving device 20 to, for example, a vocal amplifier or the like, a cordless microphone system using infrared rays is realized.

FIG. 15B shows, for example, a stereo or television audio output transmitted to headphones by an infrared signal (a so-called cordless headphone system). A transmitter 30 is provided with an input terminal 31, and a stereo or television is provided. A voice signal of a desired sound source such as John's voice output can be input. Then, a transmission modulator 32 for FM-modulating a carrier signal of, for example, 2.3 MHz and 2.8 MHz by an input audio signal is provided, and an LED (light emitting diode) is driven by the FM-modulated L and R stereo signals to generate infrared rays. A light emitting unit 33 that outputs a signal is provided.

On the other hand, in the headphone 40 receiving the infrared output from the transmitter 30, for example, a light receiving section 41 which receives an infrared signal by a light receiving element such as a photodiode and converts it into an electric signal, and a light receiving section 41 detects the infrared signal. A reception demodulation unit 42 that FM-demodulates / amplifies the generated signal into an original audio signal and a speaker output unit 43 are provided, and thereby a cordless headphone system using infrared rays is realized. Of course, a system in which a similar infrared light receiving means is provided in the speaker amplifier instead of the headphones is also possible.

Further, an infrared cordless transmission / reception system has been proposed in combination with the systems of FIGS. 15 (a) and 15 (b). That is, as shown in FIG. 16, the output terminal 23 of the receiving device 20 is connected to the input terminal 31 of the transmitting device 30, and for example, the receiving device 20 and the transmitting device are arranged such that the light receiving unit 21 and the light emitting unit 33 are arranged on the ceiling of the room. Distribute 30.

The directivity of the infrared output of the microphone 20 is set upward, so that the sound from the microphone 20 is received by the receiving device 20 as an infrared signal,
FM demodulated and supplied to the transmission device 30. Transmitter 3
From 0, the audio signal is FM-modulated and output as infrared rays. Then, the infrared signal is received by the headphone 40, demodulated, and output as voice. In this way, the voice of the speaker with the microphone 10 is transmitted to the listener wearing the headphones 40.

In this system, the infrared output of the microphone 10 is limited to the upper direction by relaying by the receiving device 20 and the transmitting device 30, so that the infrared output level does not need to be large. In addition, since it does not transmit directly to the headphones 40, even if there is an obstacle such as a teaching platform in the horizontal transmission / reception direction, there is no problem.
In addition, setting the output level and directivity of the transmitting device 30 or disposing a plurality of transmitting devices 30 has the advantage that voice can be transmitted to a wider range of listeners.

[0009]

However, as shown in FIG.
When implementing such a transmission / reception system, the infrared output from the transmission device 30 is transmitted to the headphones 4 as shown by the dotted line in the figure.
Not only 0, but also the receiving device 20 receives it, and if the modulation frequencies in the microphone system and the headphone system are close to each other, or if they are the same, there is a problem that a beat failure occurs. Yes, it hindered the implementation of this transmission / reception system.

[0010]

The present invention has been made in view of the above problems, and an audio signal from a sound source is sent from a transmission unit (for example, a microphone) to the relay unit as an infrared signal, and the relay unit transmits infrared light. In a system for supplying an audio signal to a receiving unit (for example, a headphone) by a signal, a beat failure is prevented, and a light receiving means and a light emitting means in a relay unit are installed in the same space where infrared components are not blocked. As a result, at least one of the light receiving means and the light emitting means is provided with a light shielding means for preventing infrared light output from the light emitting means from being received by the light receiving means. Alternatively, the light receiving means and the light emitting means in the relay unit are arranged in such a range and direction that one or both of the light receiving directivity of the light receiving means and the light emitting directivity of the light emitting means can prevent the infrared light output from the light emitting means to be received by the light receiving means. Make sure it is set.

[0011]

It is possible to substantially prevent the output of the light emitting means in the relay unit fixed in the room from being input to the light receiving means by the light shielding means such as a shield plate or the setting of the directivity. In particular, if the output of the light emitting means is input to the light receiving means for a weak infrared component, no beat is generated. Therefore, even if the output infrared component of the light emitting means is not perfect, the light receiving means of most of the components is received. If the input to the system is prevented, there is no problem in putting the system to practical use.

[0012]

FIG. 1 shows a first embodiment of the present invention, which is a transmission / reception system including a microphone 10, a headphone 40, and a relay unit 50 formed by connecting a receiver 20 and a transmitter 30. Is shown. The internal circuit blocks of the microphone 10, the headphone 40, the receiving device 20, and the transmitting device 30 are the same as those in FIG. Further, in FIG. 1, for the relay unit 50, only the light receiving portion 21 and the light emitting portion 33 are shown, but the signal detected by the light receiving portion 21 is the same as in FIG.
As described with reference to FIG. 16, after being converted into an audio signal by the reception demodulation unit 22, it is modulated again by the transmission modulation unit 32 via the connected output terminal 23 and input terminal 31, and output from the light emitting unit 33 as an infrared signal. It is something.

As can be seen from FIG. 1, the microphone 1
The voice of a speaker with 0 is F of 3.2MHz or 3.7MHz, for example.
The infrared signal S ₁ based on the M modulation signal is received and detected by the light receiving section 21 of the relay unit 50 and demodulated as an audio signal. Then, this voice signal is again FM-modulated with respect to a carrier signal of 2.3 MHz or 2.8 MHz, for example, and is output from the light emitting unit 33 as an infrared signal S ₂ . The infrared signal S ₂ is detected by the headphone 40 including the light receiving unit 41 as shown in FIG. 2, and then is demodulated into the original audio signal by the internal reception demodulation unit and output from the speaker 43. The voice of the speaker is transmitted to the 40 wearers.

The microphone 10 is constructed as shown in FIGS. 3 to 5, so that the output directivity of the infrared signal S ₁ is directed upward. As shown in FIG. 3, the microphone 10 includes a sound collecting mechanism 2 formed by using a diaphragm, a boil coil, a magnet, or the like.
And a substrate 3a for accommodating various circuit elements (not shown) constituting the transmission modulator 12 and the like, and a battery accommodating portion 3b for accommodating a battery (dry cell) BT. It comprises a unit 3 and an infrared transmission mechanism unit 4 in which, for example, three LED light emitting elements 4b for outputting an infrared signal are arranged. 3c and 3d
Is an electrode plate in the battery housing portion 3b, and B is a screw for joining each portion. A cushion belt 5 is attached around the sound collecting mechanism 2, and a rubber ring 6 is provided around the joint between the body 3 and the infrared transmitting mechanism 4. Reference numeral 7 denotes an operation switch for turning on / off the microphone 1.

The infrared transmission mechanism portion 4 formed under the main body portion 3 is shown in an exploded perspective view of the internal mechanism of FIG. 4 and a sectional view of FIG. The cover 4a serving as an outer casing is made of a material that can transmit at least infrared rays and is formed in a vertically long dome shape. Reference numeral 4c indicates a substrate on which the LED light emitting element 4b and a predetermined circuit element are mounted. The substrate 4c includes a damper 4d having elasticity and formed of, for example, an elastomer, and A
It is held in close contact with a holding ring 4e that is made of a BS resin and is colorless and transparent. The damper 4d and the pressing ring 4e are fixed in the cover 4a by screws B while holding the substrate 4c.

Further, as shown in FIG. 3, infrared rays from the LED light emitting element 4b mounted downward are
A gyro mirror mechanism 8 for reflecting in a predetermined direction is provided. The gyro mirror mechanism 8 includes a support ring 8a and a horizontal body 8b. The support ring 8a arranged below the pressing ring 4e is, for example, A
It is a colorless transparent body made of BS resin and has a ring portion 8a.
₁ and a U-shaped horizontal body supporting portion 8a ₂ provided below the ring portion 8a ₁ . The upper surface of the ring portion 8a ₁ is formed slide projection 8a _3, it is circumferentially on the sliding protrusions 8a ₄ is formed on the further circumferential surface. Further, the horizontal body supporting portion 8a ₂ has a shaft hole 8a ₅ for axially supporting the horizontal body 8b.
And a shaft projection 8a ₆ is formed at the lowermost portion of the U-shaped horizontal body supporting portion 8a ₂ .

As can be seen from FIG. 5, the support ring 8a contacts the bottom surface of the pressing ring 4e at the sliding projection 8a ₃ and also contacts the inner peripheral surface of the cover 4a at the sliding projection 8a ₄ , and further the shaft projection. 8a not fixed only by contacting loosely fitted and a shaft recess 4a ₂ provided on the inner surface at the bottom of the cover 4a at _6. Therefore, the microphone 1 is rotatable in the direction of rotation with respect to the central axis of the main body of the microphone 1 (direction of arrow K _{1 in} FIG. 4).

The horizontal body 8b is pivotally supported by the horizontal body supporting portion 8a ₂ of the support ring 8a. That is, the axial projections 8b ₁ is formed to be inserted into the shaft hole 8a _5, whereby the horizontal member 8b rotates in the direction of rotation with respect to the central axis of the shaft projections 8b ₁ (arrow K ₂ direction in FIG. 4) It is free. Further, the main body portion 8b ₂ of the horizontal body 8b is formed in a hemispherical shape,
The upper plane is the mirror portion 8b ₃ . Further, the lower portion of the hemispherical main body portion 8b ₂ is formed by a weight 8b ₄ .

In the infrared transmitting mechanism 4 thus constructed, for example, when the microphone 1 is in a vertical state as shown in FIG. 6A, the mirror portion 8b ₃ is perpendicular to the main body of the microphone 1. The light emitted from the LED light-emitting element 4b attached at an angle of about 10 ° below the substrate 4c at this time is reflected by the mirror portion 8b ₃ at a predetermined reflection angle, and the infrared transmission mechanism portion. Four
The light is emitted to the outside through the cover 4a.

From this state, no matter which direction the microphone 1 is tilted, the weight 8b ₄ causes the support ring 8a to rotate in the K ₁ direction by a predetermined angle, and the horizontal body 8
Since b rotates in the K ₂ direction by a predetermined angle, the mirror portion 8b ₃ is kept horizontal as shown in FIG. 6B. Also in this case LE
The light output from the D light emitting element 4b is reflected by the mirror portion 8b ₃ at a predetermined reflection angle, and the cover 4 of the infrared transmission mechanism portion 4 is reflected.
It is emitted to the outside through a.

Further, no matter which direction the microphone 1 is tilted by 90 °, the support ring 8a and the horizontal body 8b are similarly rotated by a predetermined angle by the action of the weight 8b ₄ , as shown in FIG. 6 (c). The mirror portion 8b ₃ is kept horizontal. In this case, light output from the LED light emitting element 4b is reflected by the mirror portion 8b ₃ at a predetermined reflection angle, or directly, and is emitted to the outside from the infrared transmitting mechanism 4 through the cover 4a.

For example, with the structure of the infrared transmitting mechanism 4 as described above, the infrared signal S ₁ from the microphone 10 is always output upward, and the voice signal from the microphone 10 is well detected by the light receiving portion 21 of the relay unit 50. It

The light receiving portion 21 of the relay unit 50 is constructed as shown in FIG. 7, for example. That is, a rotatable pedestal portion 21b is provided on a base 21a having a means for attaching to a ceiling or the like, and a parabolic mirror 21c is pivotally rotatable on the pedestal portion 21b. A photodiode 21d is mounted as a light receiving element on the central bottom of the parabolic mirror 21c. Reference numeral 21e indicates a dome-shaped cover that transmits infrared rays. In the light receiving section 21, infrared rays are efficiently collected by the photodiode 21d by the parabolic mirror 21c, and the directivity of infrared ray detection can be controlled by the swinging angle of the parabolic mirror 21c and the rotating position of the pedestal portion 21a.

On the other hand, the light emitting section 3 in the relay unit 50
3 is configured as shown in FIG. 8A, for example, a main body portion 33c in which a plurality of light emitting elements (LEDs) 33b are arranged is formed on a base portion 33a, and a rear surface and both side surfaces of the main body portion 33c. Is a material that does not transmit infrared rays
As a result, the output directivity of the infrared signal S ₂ from the light emitting portion 33 is within the range W as shown in FIG. 8B.
Limited to s. Note that 33e is a front cover formed of a material that transmits infrared rays.

In the transmission / reception system in which the light receiving portion 21 and the light emitting portion 31 are arranged on the ceiling as shown in FIG. 1, no beat failure occurs. That is, the light emitting portion 33 is provided with the shielding plate portion 33d, and the light emitting portion 33 is provided.
Since all d are arranged so that the shield plate portion 33d side faces the direction of the light receiving portion 21, the infrared signal S ₂ from the light emitting portion 33d is hardly received by the light receiving portion 21. Therefore, the infrared cordless transmission / reception system using the relay unit 50 can be satisfactorily implemented.

If a plurality of light receiving portions 21 are arranged as shown in FIG. 9, the infrared signal S ₁ from the microphone 20 can be satisfactorily transmitted to the relay unit 50 regardless of the position of the speaker in the room.
Can be transmitted to. However, in this case, the light emitting unit 33
For the light receiving section 21 which may fall within the range of the output directivity, the light receiving input directivity is set to Wj as shown in the figure by setting the rotation position of the pedestal 21b and the swing angle of the parabolic mirror 21c. It is necessary to set in the range of.

FIGS. 10 (a) and 10 (b) show an embodiment in which the arrangement is different. FIG. 10 (a) shows the state of the room seen from the wall direction, and FIG. 10 (b) shows the state seen from the ceiling side. .. This is a system in which the light receiving section 21 is attached to each of the four corners of the ceiling and the light emitting section 33 is attached to a desired position on the wall surface. In this case, since the light shielding plate portion 33d side of the light emitting portion 33 faces the ceiling side, the beat failure does not occur. Especially, this example is effective for a relatively small room.

FIG. 11 shows an embodiment in which the light emitting portion 33 is horizontally installed on the ceiling and the light receiving portion 21 is arranged at a position that is appropriately separated. Then, the light receiving input directivity of the light receiving unit 21 is set so as to be in the range Wj centered right below. In this case, it is not necessary to provide the light emitting portion 33 with a light shielding plate portion.

FIG. 12 shows an embodiment using a light receiving and emitting section 60 in which the light receiving section 21 and the light emitting section 33 are integrated. In this case,
The light receiving and emitting unit 60 may be attached to a desired position on the ceiling or the wall surface.

The light receiving and emitting section 60 is, for example, as shown in FIG.
The parabolic mirror 61 is located at a position slightly protruding from the base portion 65.
Is attached, and the light receiving element 62 is arranged at the center bottom thereof, and the light emitting element 63 is arranged on the base portion 65 on the back side of the parabolic mirror 61. Reference numeral 64 denotes a cover formed on the dome with a material that transmits infrared rays. In the case of the light receiving / emitting unit 60, the parabolic mirror 62 has a function as a shielding plate, so that the infrared signal S ₂ from the light emitting element 63 is not received by the light receiving element 62. Therefore, no beat failure occurs.

Further, the light receiving / emitting section 60 used in the system of FIG. 12 may be constructed as shown in the sectional views of FIGS. 14 (a) and 14 (b). That is, the parabolic mirror 61 is attached at a position slightly protruding from the base portion 65, the light receiving element 62 is arranged at the center bottom portion thereof, and the flange-shaped element loading portion 66 is provided around the parabolic mirror 61.
The light emitting element 63 is arranged on the element mounting portion 66. In this case, as can be clearly seen from FIG.
2 is located rearward with respect to the emission direction of the light emitting element 63, and is outside the output directivity range of the light emitting element 63. Therefore, the infrared signal S ₂ from the light emitting element 63 is received by the light receiving element 6
2 does not receive light, and no beat disturbance occurs.

Although various embodiments have been shown above, the light emitting portion 33 of the relay unit 50 can be controlled by providing a light shielding means on one or both of the light receiving portion 21 and the light emitting portion 33 or controlling the directivity. Infrared output of the receiver 2
It suffices that the system layout is configured so that it is not input or is difficult to be input to 1, and various other examples can be considered.

In the embodiment, the transmission / reception system having the relay unit 50 formed by connecting the receiving device 20 and the transmitting device 30 is shown. However, for example, the receiving device 20 and the transmitting device 30 are not connected, Even when the microphone system and the headphone system are separately used as shown in FIG. 15, by applying the present invention to the light receiving unit 21 and the light emitting unit 33, the microphone system and the headphone system are provided in the same space (same space). Room) can be used.

[0034]

As described above, the infrared transmission / reception system of the present invention is a system in which a voice signal is sent from the transmission unit to the relay unit as an infrared signal, and the relay unit again supplies the voice signal to the reception unit as an infrared signal. As the light receiving means and the light emitting means in the relay unit, one or both of the light receiving means and the light emitting means is provided with a light shielding means, or by controlling the directivity,
There is an effect that the infrared output from the light emitting means is prevented from being input to the light receiving means, and the occurrence of the beat trouble can be avoided. As a result, the infrared cordless transmission / reception system using the relay unit can be easily put into practical use.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an arrangement state of a first embodiment of an infrared transmission / reception system of the present invention.

FIG. 2 is a perspective view of a headphone used in the embodiment.

FIG. 3 is a structural diagram of a microphone used in an example.

FIG. 4 is an exploded perspective view of an infrared transmission mechanism portion of a microphone used in the embodiment.

FIG. 5 is a cross-sectional view of an infrared transmission mechanism portion of a microphone used in an example.

FIG. 6 is an operation explanatory diagram of an infrared transmission mechanism section of the microphone used in the embodiment.

FIG. 7 is a perspective view of a light receiving unit used in the embodiment.

8A and 8B are a perspective view and a directivity explanatory view of a light emitting unit used in an example.

FIG. 9 is an explanatory diagram of an arrangement state and a directivity state of the second embodiment.

FIG. 10 is an explanatory diagram of an arrangement state and a third embodiment.

FIG. 11 is an explanatory diagram of an arrangement state and a directivity state of the fourth embodiment.

FIG. 12 is an explanatory diagram of an arrangement state of a fifth embodiment.

FIG. 13 is a perspective view of a light emitting / receiving unit used in the fifth embodiment.

FIG. 14 is a perspective view and a cross-sectional view of another light receiving and emitting section used in the fifth embodiment.

FIG. 15 is a configuration diagram of a microphone system and a headphone system.

FIG. 16 is an explanatory diagram of an infrared transmission / reception system using a microphone system and a headphone system.

[Explanation of symbols]

 10 Microphone 20 Receiving device 21 Light receiving part 21c Parabolic mirror 21d Light receiving element 30 Transmitting device 33 Light emitting part 33b Light emitting element 33d Shielding plate part 40 Headphone 50 Relay unit 60 Light receiving and emitting part

Claims (2)

[Claims] 1. A transmission unit that outputs an input signal as an infrared signal, a light receiving unit that receives the infrared signal output from the transmission unit, a reception processing unit for the received signal, and an output of the reception processing unit. A relay unit having a transmission processing means capable of performing processing for transmitting, a light emitting means for outputting an output of the transmission processing means as an infrared signal, and an infrared signal output from the relay unit. In the infrared transmission / reception system, which comprises a receiving unit for performing demodulation and reproduction processing, the light receiving means and the light emitting means in the relay unit are installed in the same space where infrared components are not blocked, and the light receiving means is provided. And at least one of the light emitting means prevents the infrared light output from the light emitting means from being received by the light receiving means. Infrared transceiver system, wherein the order of the shading means. 2. A transmission unit that outputs an input signal as an infrared signal, a light receiving unit that receives the infrared signal output from the transmission unit, a reception processing unit for the received signal, and an output of the reception processing unit. A relay unit having a transmission processing means capable of performing processing for transmitting, a light emitting means for outputting an output of the transmission processing means as an infrared signal, and an infrared signal output from the relay unit. In the infrared transmission / reception system, which comprises a receiving unit for performing demodulation and reproduction processing, the light receiving means and the light emitting means in the relay unit are installed in the same space where infrared components are not blocked, and the light receiving means is provided. One or both of the light receiving directivity in the light emitting means and the light emitting directivity in the light emitting means are infrared rays from the light emitting means. Infrared transceiver system, wherein the force is set to a range and direction can be prevented from being received to the light receiving means.