JP2619135B2 - Pulse optical power supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a pulsed light feeding device for transmitting pulsed light from a signal processing device to a terminal device for feeding and data transmission.

(Prior Art) FIG. 9 is a configuration diagram of such a pulsed light feeding device. The signal processing device A is provided with a power supply 1, and the semiconductor laser 2 is connected to the power supply 1. On the other hand, the terminal device B includes the photodiode 3 and is connected to the primary coil of the transformer 4. An electronic device 5 is connected to a secondary coil of the transformer 4. The transformer 4 also has a function of impedance matching between the photodiode 3 and the electronic device 5. An optical fiber 6 is arranged between the semiconductor laser 2 and the photodiode 3.

With such a configuration, the semiconductor laser 2 emits pulsed laser light by a pulse voltage supplied from the power supply 1. This pulsed laser light is emitted for a predetermined period at a period C as shown in FIG. It should be noted that the hatched portion in FIG. 7 indicates a period during which pulsed laser light is output. This pulse laser light is transmitted through the optical fiber 6 and received by the photodiode 3. The photodiode 3 photoelectrically converts the received pulse laser light to obtain a voltage signal. The transformer 4 boosts this voltage signal and supplies it to the electronic device 5. That is, power is supplied to the electronic device 5.

On the other hand, when data communication is performed from the signal processing device A to the terminal device B, the signal processing device A stops supplying power by the pulse laser beam and performs data communication in the period Q as shown in FIG. This data communication transmits data by the NRZ method.

However, when the power supply by the pulse laser light is stopped and data communication is performed, a sufficient amount of light is not transmitted because the supply of the pulse laser light is intermittent, and the power supplied to the terminal device B gradually decreases. . For this reason, the electronic device 5 does not operate sufficiently. To solve this problem, it is sufficient to supply a sufficient amount of light to the terminal device B in advance, but the life of the semiconductor laser 2 is proportional to the second to fourth power of the light emission energy. The service life becomes extremely short. Therefore, the data communication needs to be performed within a period in which the operable level voltage _VQ is supplied to the electronic device 5. Therefore, the efficiency of data communication is low.

(Problems to be Solved by the Invention) As described above, the power supplied to the terminal device during the data communication period decreases, and the efficiency of data communication deteriorates.

Therefore, an object of the present invention is to provide a pulsed light power supply device capable of reliably supplying power even during data communication and improving data communication efficiency.

[Configuration of the Invention] (Means for Solving the Problems) According to the present invention, power is supplied from a signal processing device to a terminal device by sending and receiving pulse light between the signal processing device and the terminal device, and data is transmitted and received. At least the signal processing device is a pulse light power supply device that achieves the above object by providing pulse light transmitting means for obtaining pulse light by performing phase modulation with each code having a different high-level period.

(Operation) With the provision of such means, at least the pulse light transmitting means of the signal processing device transmits pulse light phase-modulated in accordance with each code having a different high-level period within a predetermined period to the terminal device.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram of a pulsed light feeding device. A terminal device 20 is connected to the signal processing device 10 via an optical fiber 30 for transmitting light energy and an optical fiber 31 for transmitting a signal.

The signal processing device 10 includes a signal processing unit 11.
The signal processing unit 11 has a function of transmitting a pulse signal that goes high every predetermined period and performing data communication using a bi-phase code phase shift modulation method. This bi-phase code changes from high level to low level within the period S as shown in FIG.
Is set to "1", and a signal E which changes from low level to high level within the same period S and has a mark ratio of 50% is set to "0". Accordingly, the signal processing unit 10 combines the signals R and E and sends out data consisting of "1" and "0".

The signal processing unit 10 includes a control drive circuit via an adder 12.
13 is connected. This control drive circuit 13 is a signal processing unit
It has a function of driving the semiconductor laser 14 in response to data from 10. The pulse laser light output from the semiconductor laser 14 is disposed so as to enter the optical fiber 30. A part of the pulse laser light output from the semiconductor laser 14 is incident on the photodiode 15 for automatic light quantity control. An electric signal corresponding to the amount of received light output from the photodiode 15 is input to the adder 12 through the amplifier circuit 16.

Further, a separation / demodulation circuit 18 having a photodiode 17 is connected to the signal processing unit 11. The photodiode 17 is disposed at the output end of the optical fiber 31, and this optical fiber 31
Has the function of receiving an optical pulse signal that transmits the signal and converting it into an electric signal. The separation / demodulation circuit 17 has a function of separating an electric signal obtained by photoelectric conversion of the photodiode 18 by a signal component.

On the other hand, the terminal device 20 has a function of processing the detection data of the physical quantity detected by the detector 21 according to the data sent from the signal processing device 10. Specifically, it has the following configuration. A photodiode 23 is connected to a primary coil of the transformer 22. This photodiode
Reference numeral 23 is disposed at the output end of the optical fiber 30 and converts the pulse laser light transmitted through the optical fiber 30 into an electric signal. A comparator 25 is connected to a secondary coil of the transformer 22 via a rectifier circuit 24. The comparator 25 has a function of, when the voltage level appearing on the secondary coil of the transformer 22 is higher than a predetermined level, supplying the voltage to the circuits constituting the terminal device 20, such as the control circuit 26. A signal demodulation circuit 27 is connected to the secondary coil of the transformer 22. The signal demodulation circuit 27 has a function of demodulating an electric signal appearing on the secondary coil of the transformer 22 into data consisting of “1” and “0” and sending the data to the control circuit 26. The control circuit 26 is connected to the signal processing unit 28 and the modulation circuit 29 and has a function of controlling the operation of the signal processing unit 28 and the modulation circuit 29. The signal processing section 28 detects the detector 21 according to the received data.
Has a function of processing detection data from The modulation circuit 29 controls the data processed by the signal processing unit 28
It has a function of operating the semiconductor laser 32 by modulating this data into an optical pulse signal in response to the command of 26.

Next, the operation of the apparatus configured as described above will be described.

First, the operation when data communication is stopped will be described. The signal processing unit 10 outputs data that repeats a high level and a low level in a cycle S. In this case, the mark rate of this data is 50%. This data is sent to the control drive circuit 13 through the adder 12. The control drive circuit 13 drives the semiconductor laser 14 upon receiving the data. As a result, the semiconductor laser 14 repeats the output of the pulse laser light at a period S as shown in FIG. This pulse laser light enters the optical fiber 30 and is transmitted to the terminal device 20. At this time, a part of the pulsed laser light output from the semiconductor laser 14 is received by the photodiode 15, and this photodiode 15
Outputs an electric signal corresponding to the amount of received light. This electric signal is fed back to the adder 12 through the amplifier circuit 16.
Thereby, the control drive circuit 13 controls the laser output intensity of the semiconductor laser 14 to be constant.

The pulse laser light transmitted through the optical fiber 30 is used as a terminal device.
The light is received by the 20 photodiodes 23 and converted into voltage signals. This voltage signal is boosted by the transformer 22 and sent to the comparator 25 through the rectifier circuit 24. If the voltage level appearing on the secondary coil of the transformer 22 is higher than a predetermined level, the comparator 25 supplies the voltage to each circuit constituting the terminal device 20, such as the control circuit 26.

In this state, the signal processing unit 28 collects detection data from the detector 21 and the like.

 Next, an operation during data communication will be described.

The signal processing device 11 has a reference numeral "1" shown in FIG. 2 and FIG.
Data communication is performed by a bi-phase code shift keying scheme using “0”. For example, when transmitting the data “010...”, The signal processing unit 10 outputs a low level, a high level in the first cycle S, a high level in the next cycle S, a low level, a low level in the next cycle S, a high level, and so on. Send a signal consisting of
This signal is sent to the control drive circuit 13 through the adder 12, so that the semiconductor laser 14 outputs pulse laser light at the timing shown in FIG. This pulsed laser light is transmitted to the terminal device 20 through the optical fiber 30 in the same manner as described above. The pulse laser light is received by the photodiode 23, converted into a voltage signal, boosted by the transformer 22, and sent to the comparator 25 through the rectifier circuit 24. This comparator 25
If the voltage level appearing on the secondary coil of the transformer 22 is higher than a predetermined level, the voltage is adjusted to a terminal device such as the control circuit 26.
20 are supplied to each circuit.

The voltage appearing on the secondary coil of the transformer 22 is sent to the signal demodulation circuit 27. This signal demodulation circuit 27
The electric signal appearing on the secondary side coil is demodulated into data consisting of "010 ..." and sent to the control circuit 26. The control circuit 26 receives the data from the signal demodulation circuit 27, determines the content thereof, and issues a command according to the data content. For example, the control circuit 26 sequentially passes each detection data collected by the signal processing unit 28 to the modulation circuit 29. The modulation circuit 29 operates the semiconductor laser 32 according to each detection data. This allows
The pulsed laser light output from the semiconductor laser 32 is transmitted through the optical fiber 31 to the photodiode of the signal processing device 10.
Light is received at 17. The photodiode 17 sends an electric signal corresponding to the amount of received light to the separation / demodulation circuit 18. The separation / demodulation circuit 18 separates the electric signal from the photodiode 18 into signal components and sends the signal to the signal processing unit 11. The signal processing unit 11 receives a signal and executes a predetermined process.

Thus, in the above-described embodiment, the signal processing device 10
, The pulse light phase-modulated according to the different bi-phase codes of the high-level period within the predetermined period S is transmitted.
Even when data communication is performed, power can be supplied to the terminal device 20 during the data communication, and constant power can be reliably supplied without reducing the power. Therefore, power supply to the terminal device 20 and data communication can be performed simultaneously, and data communication can be performed continuously. Further, it is not necessary to separately provide an optical fiber or the like.

Note that the present invention is not limited to the above-described embodiment, and may be modified without departing from the scope of the invention. For example,
The signal demodulation means in the terminal device 20 may be constituted by a photodiode 40 and an optical signal demodulation circuit 41 as shown in FIG. The photodiode 40 is arranged to receive a part of the optical pulse signal transmitted through the optical fiber 30. In this case, light transmission from the optical fiber 30 to the photodiode 40 branches a part of the optical pulse signal by an optical splitter such as a star coupler or a beam splitter.
The optical signal demodulation circuit 41 has a function of receiving an electric signal from the photodiode 40, demodulating the signal into “1” and “0” signals, and sending the signal to the control circuit 26.

Also, in order to prevent the frequency spectrum from being spread due to the contents of the communication data, the same reference numerals are used as shown in FIG.
It may be transmitted repeatedly. That is, the signal processing unit 11 transmits, for example, the data “0101...”, Converts it to “00110011. This allows
The spread of frequency components due to data is reduced.

Further, a plurality of terminal devices 20 may be connected to the signal processing device 10. In this case, an optical splitter 42 such as a beam splitter is connected to the output end of the optical fiber 30, as shown in FIG.

Further, the code used for the data communication is not limited to the bi-phase code, and codes “1” and “0” may be formed such that the high-level periods are different in the cycle S as shown in FIG.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to provide a pulsed light power supply device capable of reliably supplying power even during data communication and improving the efficiency of data communication.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 4 are diagrams for explaining an embodiment of a pulsed light feeding device according to the present invention, wherein FIG. 1 is a block diagram, FIG. 2 and FIG. FIG. 4 is a waveform diagram of a biphase code, FIG. 4 is a diagram for explaining the operation of data communication, FIGS. 5 to 7 are diagrams for explaining another embodiment, and FIG. FIGS. 9 and 10 are views for explaining the prior art. 10 ... Signal processing device, 11 ... Signal processing unit, 12 ... Adder, 13 ... Control drive circuit, 14 ... Semiconductor laser, 15 ...
Photodiode, 16… Amplifier circuit, 17… Photodiode, 18… Separation / demodulation circuit, 20… Terminal device, 21…
Detector, 22 Transformer, 23 Photodiode, 24
…… Rectifier circuit, 25 …… Comparison circuit, 26 …… Control circuit, 27…
... signal demodulation circuit, 28 ... signal processing unit, 29 ... modulation circuit,
30,31 ... optical fiber, 32 ... photodiode.

Claims (1)

(57) [Claims] 1. A pulse light power supply device for supplying power from said signal processing device to said terminal device and transmitting and receiving data by transmitting and receiving pulse light between the signal processing device and the terminal device, wherein at least the signal A pulse light feeding device, characterized in that the processing device includes pulse light transmitting means for obtaining the pulse light by performing phase modulation with each code having a different high-level period.