JPH0583197A - Digital audio equipment - Google Patents

Abstract

PURPOSE:To continue miniaturization by using one transmission to interconnect an operating section and a control section and superimposing a 2-way transmission signal onto a signal on a transmission line. CONSTITUTION:In a digital audio equipment in which a digital signal is sent in a direction through a transmission line between an operating section 1 and a control section 2 and 1st and 2nd control signals are sent in 2-way through other transmission line, the operating section 1 and the control section 2 are interconnected by an optical transmission line 5, and a half mirror 14 (24) is arranged to an end of the optical transmission line 5 connecting respectively to the operating section 1 (control section 2), and the half mirrors 14, 24 are used to transmit or reflect a reception optical signal and a transmission optical signal respectively thereby separating or combining the signals, and a 1st optical signal corresponding to the digital signal and 2nd and 3rd optical signals corresponding to the 1st and 2nd control signals are sent through the optical transmission line 5 in time division.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital audio device in which an operating section and a control section are connected by a transmission line, and in particular, the transmission line is composed of one optical transmission line, The present invention relates to a digital audio device for time-divisionally transmitting various signals transmitted to and received from a control unit to the optical transmission line, and for turning on / off a signal output according to a usage state of the optical transmission line, for example, a CD. (Compact disc) Suitable for use in a changer device.

[0002]

2. Description of the Related Art Conventionally, a CD changer device, which is a typical one of the above-mentioned digital audio devices, has one optical cable and one cable between a CD changer which is an operating part and an audio controller which is a control part. Optical cable corresponding to the digital audio signal transmitted from the CD changer side to the audio controller side,
The wire cable has a first control signal transmitted from the audio controller side to the CD changer side,
The second control signal transmitted from the CD changer side to the audio controller side is transmitted.

FIG. 3 is a block diagram showing the outline of the configuration of the conventional CD changer device.

In FIG. 3, 1 is a CD changer and 2 is a CD changer.
Is an audio controller, 3 is an optical cable, 4 is a wire cable, 11 is a data processor, 12 is a transmitter, 13 is a system controller, 21 is a receiver, and 22 is a digital signal processor (DS).
P) and 23 are system controllers.

The CD changer 1 is composed of a data processor 11, a transmitter 12 and a system controller 13. The audio controller 2 is composed of a receiver 21, a digital signal processor 22 and a system controller 23. An optical cable 3 is connected between the transmitter 12 and the receiver 21, and a wire cable 4 is connected between the two system controllers 13 and 23.
Are combined.

The operation of the CD changer device is as follows.

First, on the audio controller 2 side, the system controller 23 causes the CD changer 1 to operate in response to a request from the digital signal processor 22.
, A first control signal including instruction contents such as CD play, CD place top, CD conversion, specific CD designation, and cueing is generated, and the first control signal is transmitted through the wire cable 4. Send to CD changer 1.

At this time, in the CD changer 1, when the system controller 13 receives the first control signal, the system controller 13 supplies a control command signal corresponding to the instruction content to the data processor 11, and the data processor 11 Then, the control corresponding to the instruction content is performed. As a result, when the CD is played according to the instruction, the data processor 11 generates a digital audio signal and a second control signal including information indicating the operating state of the CD player and time information. , The digital audio signal is supplied to the transmitter 12, and the second control signal is supplied to the system controller 13. Then transmitter 12
First, the received digital audio signal is applied to a modulator to modulate a carrier wave, then the modulated carrier wave signal obtained here is converted into an optical signal, and this optical signal is passed through the optical cable 3 to the audio controller 2 Send to.
Further, the system controller 13 sends the received second control signal to the audio controller 2 through the wire cable 4.

On the audio controller 2 side again, when the receiver 21 receives the optical signal, the receiver 21 first performs optical-electrical conversion of the optical signal to convert it into a modulated carrier signal, and then The modulated carrier wave signal is added to a demodulator and demodulated to reproduce the original digital audio signal, and then the reproduced digital audio signal is supplied to the digital signal processor 22. The digital signal processor 22 controls an audio signal by this digital audio signal. In addition, the digital data is
It is transmitted to the control unit 23 via the optical fiber 25 for transmission optical signal, and then the control unit 2
3 is transmitted to the second slave unit 21 via the optical fiber 26 for the received optical signal, and the system controller 23 receives the second control signal, the first control signal is transmitted in response to the second control signal. Adjust control signals,
It also controls the operation of the digital signal processor 22.

[0010]

In the conventional CD changer device, the digital audio signal is transmitted through the optical cable 3 in the form of an optical signal, and the first and second control signals are transmitted through the wire cable 4 in the form of an electrical signal. Since two signals of different signal formats, such as transmission, are transmitted through separate transmission lines, they are suitable for different transmission systems on both the CD changer 1 side and the audio controller 2 side. Since it is necessary to provide the two signal coupling portions described above, the structure of the CD changer device becomes complicated, and the device becomes large in size, so that there is a problem that it cannot be manufactured at low cost.

Further, in the conventional CD changer apparatus, since the optical signal corresponding to the digital audio signal generated by the CD changer 1 is turned on / off on the audio controller 2 side, the optical signal is turned on / off. Switch to perform audio controller 2
If the optical signal is not used and the switch is held in the ON state, the phase locked loop (PLL) in the digital signal processor 22 will have a large jitter and the reproduction will be increased. There was also a problem that the sound quality of the received signal deteriorates.

The present invention eliminates these problems, and a first object of the present invention is to provide a single transmission line for coupling between the actuating section and the control section, and to both the transmission lines. It is an object of the present invention to provide a digital audio device that carries a signal that is transmitted bidirectionally.

A second object of the present invention is to have one transmission line connecting between the operating section and the control section, and to transmit the transmission signal on the operating section side in accordance with the usage state of the transmission line. It is an object of the present invention to provide a digital audio device that performs on / off control.

[0014]

In order to achieve the first object, the present invention transmits a digital signal in one direction between a working section and a control section through one transmission line, and
In a digital audio device for bidirectionally transmitting first and second control signals via another transmission line, one optical transmission line is coupled between the operating unit and the control unit to control the operating unit and the control unit. A half mirror is arranged at an end of each of the optical transmission lines of each section, and the received optical signal and the transmitted optical signal are respectively transmitted or reflected by these half mirrors to separate or combine them, and the digital A first optical signal corresponding to a signal and second and third optical signals corresponding to the first and second control signals are time-divisionally transmitted to the optical transmission line, respectively. ..

Further, in order to achieve the second object,
The present invention relates to a digital audio device for transmitting a digital signal between an operating unit and a control unit via a transmission line, wherein one optical transmission path is connected between the operating unit and the control unit, The part disposes a half mirror at the end of the optical transmission line, and separates the transmitted optical signal and the reflected optical signal by transmitting or reflecting the transmitted optical signal and the reflected optical signal, respectively, and the reflected optical signal. The second means for stopping the transmission of the transmission optical signal is provided only when the above is obtained.

[0016]

First, according to the first means, in the actuating section, the digital signal obtained by the operation of the device is modulated and then converted into the first optical signal. The first optical signal passes through the first half mirror, is supplied to one optical transmission line, and is transmitted to the control unit side via this optical transmission line. At the same time, the second control signal obtained by the operation of the device is also modulated and then converted into the third optical signal. This third optical signal also passes through the first half mirror and is supplied to the optical transmission line, and is transmitted to the control unit side via the optical transmission line. Then, the first optical signal and the third optical signal are not transmitted at the same time, that is, the first optical signal and the third optical signal are transmitted in a time division manner.

When the second optical signal transmitted from the control unit side to the operating unit side is received through the optical transmission line in the operating unit, the second optical signal is transmitted to the first optical signal. It is reflected by the half mirror to separate from the first and third optical signals. The second optical signal obtained here is photoelectrically converted into a first control signal, which controls the operation of the device. Also in this case, the first to third optical signals are not transmitted at the same time, that is, the first, second and third optical signals are transmitted in a time division manner.

Next, in the control section, the first and third optical signals transmitted from the actuating section side through the optical transmission path are transmitted through the second half mirror and input. Among them, the first optical signal is opto-electrically converted and then demodulated to be reproduced as an original digital signal. Similarly, the third optical signal is opto-electrically converted and then demodulated. And the second control signal is reproduced.

The control unit also converts the first control signal obtained for controlling the operation of the actuating unit into a second optical signal. The second optical signal is reflected by the second half mirror, is supplied to the optical transmission line, and is transmitted to the actuation unit side via the optical transmission line.

As described above, in the first means,
The operating unit and the control unit are coupled by one optical transmission line, and each optical signal of the optical transmission line is time-divisionally transmitted, and half mirrors are provided in both the operating unit and the control unit. Since the transmission / reception signals are separated and combined by means of, the overall configuration of the digital audio device is considerably simplified.

Next, according to the second means, the digital signal obtained by the operation of the device is converted into the transmission optical signal by the optical-electrical conversion in the operating section, and the transmission optical signal is transmitted through the half mirror. It is transmitted and supplied to one optical transmission line.

At this time, the half mirror receives the reflected light from the coupling portion of the operating portion and the optical transmission line and the reflected light transmitted through the optical transmission line, and reflects the reflected light by the half mirror. To separate it from the transmitted optical signal. Next, the reflected light is photoelectrically converted, and then analog-digital converted and supplied to the system controller. When the system controller receives the digitally converted signal, it stops the generation of the digital signal from the device.

As described above, in the second means,
Since the generation of the digital signal from the device is automatically stopped when the reflected light is large, that is, when the optical transmission line is not formed between the operating unit and the control unit, it is conventionally necessary. It is not necessary to provide a switch for turning on / off the optical signal, and it is possible to prevent deterioration of sound quality due to forgetting to turn off the switch.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of a CD changer device according to the present invention.

In FIG. 1, 5 is an optical cable which constitutes one optical transmission line, 14 is a first half mirror, 15 is a pin photodiode which constitutes an opto-electric conversion element, and 24
Is a second half mirror, 25 is a light emitting diode (LED) that constitutes an electro-optical conversion element, and the same components as those shown in FIG. 4 are denoted by the same reference numerals.

Then, the CD that hits the end of the optical cable 5
In the changer 1 and the audio controller 2,
The first and second half mirrors 14 and 24 are respectively arranged, the photoelectric conversion element 15 is arranged on the optical path of the reflected light of the first half mirror 14, and the reflected light of the second half mirror 24 is arranged. An electro-optical conversion element 25 is arranged on the optical path of the. The output of the opto-electric conversion element 15 is connected to the system controller 13, and the electro-optic conversion element 2 is connected.
The input of 5 is connected to the system controller 23.

The CD changer device operates as follows.

First, on the audio controller 2 side, the system controller 23 causes the CD changer 1 to play a CD, a CD place top, and a C by a request from the digital signal processor 22.
A first control signal including instruction contents such as D conversion, designation of a specific CD, and cueing is generated and supplied to the electro-optical conversion element 25. Then, the electro-optical conversion element 25 converts the first control signal into a second optical signal. Furthermore, this second
Is reflected by the second half mirror 24 by about 90 degrees and then supplied to the optical cable 5, where C is transmitted on the optical cable 5.
It is transmitted to the D changer 1.

Next, in the CD changer 1, the second optical signal transmitted on the optical cable 5 is transferred to the first optical signal.
When received by the half mirror 14 of, the second optical signal is reflected by the first half mirror 14 by about 90 degrees,
It is supplied to the photoelectric conversion element 15. Then, the opto-electric conversion element 15 converts this second optical signal into a first control signal and supplies it to the system controller 13. At this time, the system controller 13 supplies the control instruction signal corresponding to the instruction content of the first control signal to the data processor 11, and the data processor 11 performs the control corresponding to the instruction content. As a result, CD
When the performance is performed, the digital audio generated by the data processor 11 is supplied to the transmitter 12, and the C generated by the system controller 13 is generated.
A second control signal including information indicating the operating state of the D player and time information is also supplied to the transmitter 12. Here, the transmitter 12 adds the first received digital audio signal and the second control signal to a modulator to modulate a carrier wave, respectively, and then uses the two modulated carrier wave signals obtained here to obtain a second modulated carrier wave signal. 1st and 3rd optical signals, respectively, and these 1st and 3rd optical signals are converted into 1st and 3rd optical signals.
It sends it toward the half mirror 14 of. At this time, the first
The third and third optical signals are supplied to the optical cable 5 after passing through the first half mirror 14, and are transmitted to the audio controller 2 on the optical cable 5.

Subsequently, on the audio controller 2 side, when the second half mirror 24 receives the first and third optical signals transmitted on the optical cable 5, the first and third optical signals are received. Is transmitted to the second half mirror 24 and supplied to the receiver 21. Next, the receiver 21 first photoelectrically-electrically converts the first and third optical signals into two modulated carrier signals, and then demodulates the two modulated carrier signals. In addition to the demodulation, the original digital audio signal and the second control signal are reproduced. Then, the reproduced digital audio signal is supplied to the digital signal processor 22 and used there for controlling the audio signal, and the reproduced second control signal is supplied to the system controller 23 where the first digital signal is reproduced. It is used for adjusting the control signal of (1) and controlling the operation of the digital signal processor 22.

In this case, when transmitting the above-mentioned first to third optical signals, the system controller 23 or the two system controllers 13 and 23 control the optical cables 5 for the first, second and third optical signals. The transmission time of each optical signal is adjusted so that the first to third optical signals are not transmitted at the same time, that is, these first to third optical signals are transmitted in a time-division manner. It is assigned.

FIG. 2 is a signal configuration diagram showing an example of allocation of transmission times of the first, second and third optical signals on the optical cable 5.

In FIG. 2, the first optical signal corresponding to the digital audio signal transmitted from the CD changer 1 side to the audio controller 2 side is assigned from time t0 to time t1, and the subsequent time t1 to t2.
The second optical signal corresponding to the first control signal transmitted from the audio controller 2 side to the CD changer 1 side is allocated during the period up to, and the CD changer 1 side during the next time t2 to t3. Is assigned a third optical signal corresponding to the second control signal transmitted from the audio controller 2 to the audio controller 2 side, and subsequent time t3 to t4
Until then, it is assigned so that no optical signal is transmitted. After this, the same as the above-mentioned allocation, the time t
The first optical signal corresponding to the digital audio signal is from 4 to t5, and the first optical signal is from time t5 to t6.
The second optical signal corresponding to the control signal of
Up to 7, the third optical signal corresponding to the second control signal is assigned.

As described above, according to this embodiment, one optical transmission line (optical cable) 5 is coupled between the CD changer 1 which is the operating unit and the audio controller 2 which is the control unit, and The optical transmission line (optical cable) 5
Since the half mirrors 14 and 24 are used for coupling and separating the bidirectional optical signals for time-division transmission, the configuration of the signal transmission system is simplified, and the overall configuration of the CD changer device is correspondingly simplified.

In this embodiment, the optical cable 5 is used for coupling between the CD changer 1 and the audio controller 2, but the distance between the CD changer 1 and the audio controller 2 is relatively short and they are If there is no obstacle to the optical signal between the optical cable 5 and the CD changer 1
The optical signal may be directly transmitted between the audio controller 2 and the audio controller 2.

Next, FIG. 3 is a block diagram showing the second embodiment of the CD changer device according to the present invention.
In particular, only the structure of the CD changer 1 is shown.

In FIG. 3, 12a is an optical transmitter, 16 is a light emitting diode (LED), 17 is an optical filter, 18 ₁ and 18 ₂ are amplifiers, 19 is an analog-digital (A-D) converter, and others. The same components as those shown in the first embodiment are designated by the same reference numerals.

In this embodiment, an optical transmitter 12a is used instead of the transmitter 12 of the first embodiment.
And an amplifier 18 ₁ is connected to the signal transmission path of the digital audio signal, and the optical transmitter 12a
Between the amplifier 18 ₂ and the system controller 13
It is connected to the -D converter 19. Further, the optical transmitter 12a includes a half mirror 14, a light emitting diode 16, a pin photodiode 15, and an optical filter 17.

The CD changer device of this embodiment operates as described below.

When the CD performance is performed in the data processor 11, the digital audio signal obtained thereby is transmitted through the amplifier 18 ₁ to the optical transmitter 12.
is supplied to a. The optical transmitter 12a applies the digital audio signal to a modulator (not shown) to modulate a carrier wave, and then converts the modulated carrier wave signal obtained here into a transmission light signal by a light emitting diode 16 and then transmits the signal. The optical signal is supplied to the optical cable (fiber) 5 via the half mirror 14.

At this time, the optical cable 5, the optical transmitter 12a and / or the audio controller 2
When the coupling with the optical transmitter (not shown) (not shown) is disconnected or the coupling is incomplete, the transmitted optical signal is reflected at the incomplete coupling portion, The obtained reflected wave is re-input to the optical transmitter 12a. Then, after being reflected by the half mirror 14, the reflected wave is supplied to the pin photodiode 15 via the optical filter 17, and is converted into an electric signal there. Then, this electric signal is supplied to the A-D converter 19 through an amplifier 18 _2, where it is converted into a digital signal, the system controller 1
3 is supplied. Upon receiving this digital signal, the system controller 13 controls the data processor 11 so that the digital audio signal is not output from the data processor 11.

In the above case, when the optical cable 5 and the optical transmitter 12a are completely coupled and the reflected wave disappears, the digital signal supplied to the system controller 13 also disappears. It is controlled so that the digital audio signal is output from 11.

According to this embodiment, the reflected wave transmitted through the optical cable 5 or the reflected wave reflected at the end of the optical cable 5 on the CD changer 1 side is separated by the half mirror 14, and the separated reflected wave is optically reflected. After passing through the filter 17, it is detected by the pin photodiode 15, the analog signal obtained thereby is converted into a digital signal and taken into the system controller 13, and the output of the data processor 11 is turned on and off by its control output. Therefore, it is not necessary to provide a switch for turning on / off the digital audio signal on the audio controller 2 side. Moreover, since the digital audio signal is effectively transmitted from the CD changer 1 side to the audio controller 2 side only when the optical cable 5 is connected,
The influence on the PLL provided in the audio controller 2 is reduced, and the deterioration of the sound quality of the reproduced signal can be prevented.

Although the above description of each embodiment has been made by exemplifying the CD changer device as the digital audio device, the digital audio device according to the present invention is not limited to the CD changer device and other similar devices. Of the above, for example, a digital audio tape recorder (DAT) device. Also, as the digital signal transmitted from the operating unit to the control unit, a CD-ROM signal can be used in addition to the digital audio signal described in each of the above-described embodiments.

[0046]

According to the first aspect of the invention, the operating section (CD changer) 1 and the control section (audio controller) 2 are connected by one optical transmission line (optical cable) 5, and Each optical signal transmitted through the optical transmission line 5 is time-division transmitted, and the operating unit 1 and the control unit 2
Since the bidirectional optical signals are separated and combined by the half mirrors 14 and 24 on both sides, the configuration of the signal transmission system is remarkably simplified, which considerably simplifies the overall configuration of the digital audio device and also reduces the size. And the digital audio device can be manufactured at low cost.

According to the second aspect of the invention, the reflected wave transmitted through the optical transmission line (optical cable) 5 or the reflection reflected at the end of the optical transmission line 5 on the side of the operating portion (CD changer) 1 The wave is separated by the half mirror 14, and the separated reflected wave is converted into an optical-electrical conversion element (pin photodiode).
Since the analog signal obtained by the detection by 15 is converted into a digital signal and taken into the system controller 13, the output of the data processor 11 is turned on and off by its control output. ) There is no need to provide a switch for turning on / off the digital audio signal on the second side. Further, since the digital audio signal is effectively transmitted from the operating unit 1 side to the control unit 2 side only when the optical transmission line 5 is connected, the PLL provided in the control unit 2
It is possible to prevent the sound quality of the reproduced signal from being deteriorated.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of a CD changer device according to the present invention.

FIG. 2 is a signal configuration diagram showing an example of allocation of transmission times of first, second, and third optical signals on an optical cable.

FIG. 3 is a block diagram showing a second embodiment of the CD changer device according to the present invention.

FIG. 4 is a block diagram showing an example of a conventional CD changer device.

[Explanation of symbols]

1 CD Changer 2 Audio Controller 5 Optical Cable 11 Data Processor 12 Transmitter 12a Optical Transmitter 13, 23 System Controller 14, 24 Half Mirror 15 Optical-Electrical Conversion Element 16, 25 Electrical-Optical Conversion Element 17 Optical Filter 18 ₁ , 18 ₂ Amplifier 19 Analog-digital (A-D) converter 21 Receiver 22 Digital signal processor (DSP)

Claims (3)

[Claims] 1. A digital signal is unidirectionally transmitted between an operating unit and a control unit via one transmission line, and bidirectional transmission of first and second control signals is performed via another transmission line. In the digital audio device, a single optical transmission line is coupled between the operating unit and the control unit, and half mirrors are arranged at the ends of the optical transmission lines of the operating unit and the control unit, respectively. Of the first optical signal corresponding to the digital signal, and the first and second optical signals corresponding to the digital signal by separating or combining the received optical signal and the transmitted optical signal by transmitting or reflecting respectively. A digital audio apparatus, wherein second and third optical signals corresponding to a control signal are time-divisionally transmitted to the optical transmission line, respectively. 2. A digital audio apparatus for transmitting a digital signal between a working section and a control section through a transmission line, wherein one optical transmission line is coupled between the working section and the control section, The actuating unit arranges a half mirror at the end of the optical transmission line, and transmits or reflects the transmitted light signal and the reflected light signal by the half mirror to separate them, and A digital audio device, characterized in that the transmission of the transmission optical signal is stopped only when a signal is obtained. 3. The digital audio device according to claim 1, wherein the digital audio device is a CD changer device, the operating unit is a CD changer, and the control unit is an audio controller.