JP2915109B2 - Optical wireless system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical wireless system for performing data transmission with terminal devices distributed and arranged at arbitrary positions.

(Technical Background) In data transmission, an optical wireless method is being used in addition to a conventional wired cable or wireless method. According to the optical wireless communication, it is possible to avoid troublesomeness due to troublesome wiring in a wired cable and mutual interference and noise in a wireless communication.

(Prior Art) Practical transmission systems include a wireless relay system shown in FIG. 9 (A) and an optical transmission system shown in FIG. 9 (B).

The radio relay system using radio waves shown in FIG.
The transmission wave from the mobile terminal 30 is received by the reception unit 32R of the relay device 31, retransmitted from the transmission unit 32T and received by the mobile terminal 33, and relaying covering a relatively wide area is possible.

However, in such a wireless relay system, the mobile terminal
If the relationship between the transmission frequency of the transmission device 30 and the retransmission frequency of the relay device 31 and the separation distance between the reception unit 32R and the transmission unit 32T of the relay device 31 are not appropriate, the transmission wave from the mobile terminal 30 and the retransmission In some cases, transmission waves interfere with each other, making relaying difficult. Therefore, the transmission wave (data) from the mobile terminal 30 is temporarily stored in the relay device 31 and retransmitted at a different time.

In the optical transmission system shown in FIG. 9B, a device having a pair of light transmitting and receiving units 34 and 35 having different wavelengths is opposed to each other, and performs bidirectional transmission and reception of data light between specific devices. Since the light transmitting and receiving units 34 and 35 have stronger directivity than radio waves, they can transmit a large amount of data without being affected by external noise.

(Problems to be Solved by the Invention) However, the above-described radio relay system using radio waves has relatively low directivity, so that relaying covering a wide area can be performed, but measures for avoiding mutual interference at the time of relaying are possible. Is required, and the scale of the relay device becomes large, and real-time relay becomes difficult.

Further, the above-described optical transmission system has a relatively strong directivity, so that it is suitable for transmission and reception between specific locations, but is not suitable for performing data transmission with terminals distributed and arranged at arbitrary locations in the area. Is not valid, and expands and contracts as
It was not possible to reduce the size and easily construct a transmission system of a desired scale.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides, for example, a centralized information processing apparatus P, as shown in FIG.
A plurality of concentrators / distributors 3 that perform data transmission / reception to / from the relay device 4 using optical wireless while transmitting data to / from the centralized information processing device P; One or more relay devices 4 for relaying and transmitting data using optical wireless, and one or more terminal devices 6 for transmitting data via the concentrator / distributor 3 and the relay device 4
An optical wireless system characterized in that a repeater 5 for synchronizing transmission data is interposed between the plurality of concentrators 3.

(Operation) According to the above-described configuration, if the signals are opposite in phase between the concentrators / distributors 3 (3A, 3B), the signals are canceled out, so that the optical signal is transmitted to the relay devices 4A, 4B. This is prevented by the repeater 5 from becoming impossible.

Embodiment An embodiment of the optical wireless system according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram in which an optical wireless system is constructed by an optical transmission / reception device.

As shown in FIG. 1, the optical wireless system 1 includes a control device 2,
Collector / Distributor 3 (Master Collector / Distributor 3A, Sub Collector / Distributor 3
B), repeater 4 (4A, 4B), repeater 5, terminal 6 (6Al
~ 6An, 6Bl ~ 6Bn), collection and distribution device 3, relay device
4. The terminal device 6 is an optical transmitting / receiving device.

This optical wireless system 1 is a system having expandability. That is, the basic system (a system including one control device 2, one master distribution device 3A, several relay devices 4Al to 4An, and a plurality of expandable terminal devices 6Al to 6An)
Extension system (a system consisting of one sub-collection / distribution device 3B, one repeater 5, several repeaters 4B1-4Bn, and a plurality of expandable terminal devices 6B1-6Bn) By doing so, it is possible to easily build an optical wireless system of a scale as needed.

Next, each device constituting each of the above-described systems will be described.

The control device 2 is connected to the centralized information processing device P by a data communication path,
It controls data transmission to and from 3A.

Collector / Distributor 3 (Master Collector / Distributor 3A, Sub Collector / Distributor 3
B) is a light receiving element (for example, a pin photodiode PPD)
This is an optical transmission / reception device having an optical wireless transmission / reception unit (transmission / reception unit 8 in FIG. 2) composed of a group and a light transmitting element (for example, a light emitting diode LED) group. These element groups are provided on the entire periphery of the collecting and distributing apparatus 3 so that transmission and reception of optical wireless can be performed uniformly in all directions.

Master collection and distribution device 3A is connected to control device 2 by connection line S, and exchanges data with control device 2.
That is, the light transmitting element group blinks according to the data from the control device 2 and is transmitted to the relay device 4, and the light from the relay device 4 is detected as an electric signal by the light receiving element group, and the data is transmitted to the control device 2. Sent to The master collection and distribution device 3A is connected to the sub collection and distribution device 3B via the repeater 5. The relationship between the master collection and distribution device 3A and the sub collection and distribution device 3B will be described later in detail.

The relay device 4 (relay devices 4A and 4B) is an optical transmitting / receiving device that relays between the concentrator / distributor 3 and the terminal device 6, and includes an optical wireless transmitting / receiving unit (first and second transmitting / receiving units) including a light receiving element group and a light transmitting element group. 2 includes a light transmitting / receiving unit 8). These element groups are also provided on the entire periphery of the relay apparatus 4 so that optical wireless transmission and reception can be performed uniformly in all directions.

The relay device 4 receives and receives an optical signal (modulated signal).
Is subjected to frequency conversion (for example, a carrier frequency [carrier frequency] is multiplied, as will be described later) to transmit and output light. The light received by the light receiving element group is detected as a weak electric signal (modulation signal), frequency-converted, and the light transmitting element group is turned on and off according to the frequency-converted signal, and is transmitted.

The terminal device 6 performs data transmission between the main device (the main device 25 in FIGS. 7 and 8) in which the terminal device 6 is installed and the relay device 4. The terminal device 6 also has an optical wireless transmission / reception unit (a transmission / reception substrate 19 in FIG. 6) including a light receiving element group and a light transmitting element group.

The collecting and distributing device 3 (3A, 3B) and the relay device 4 (4A, 4B) are incorporated in a ceiling or mounted at a relatively high position in a room. The terminal device 6 (6Al to 6An, 6Bl to 6Bn) is
5) Used by being incorporated in.

Next, the overall configuration of data collection and distribution will be described. The master collection and distribution device 3A performs data collection and distribution with the control device 2 via the connection line S, which is a data communication line, and displays a plurality of relay devices 4Al to 4An (only two relay devices 4A are displayed in FIG. ) Is performed via communication paths A and D, which are optical wireless communication paths. The relay device 4A is a terminal device 6 (6Al to 6A
n) Data collection and distribution between the communication paths B and C, which are optical wireless communication paths
Done through.

The communication paths A and B are downlinks, and data distribution is performed using the downlinks. The communication paths C and D are uplinks, and data is collected using the uplinks.

Distribution of data is performed by the centralized information processing device P → control device 2 →
Connection line S → Master concentrator 3A → Communication path A (optical wireless) →
Relay device 4A → communication path B (optical wireless) → terminal device 6 (6Al to 6
An) via the route.

Data collection is performed by the terminal device 6 (6Al to 6An) → communication channel C
(Optical wireless) → Relay device 4A → Communication path D (Optical wireless) → Master concentrator / distributor 3A → Connection line S → Control device 2 → Centralized information processing device P

The optical signal used for the communication path A is
This is obtained by supplying a modulated signal obtained by modulating a data signal from the master with a predetermined carrier to all of the light transmitting element groups of the master collection and distribution device 3A.

The optical signal used for the communication path B is received by at least one of the light receiving element groups of the repeater 4A, and the modulated signal obtained by frequency-converting the received modulated signal of the carrier frequency f1 into the carrier frequency f2 is transmitted to the repeater 4A. This is obtained by supplying all the elements to the element group. The carrier frequency f2 used here is, for example, f2 = n · f1 (n is an integer) and is obtained by multiplying the carrier frequency f1.

As an optical signal used for the communication path C, a modulated signal obtained by modulating a data signal output from the main device (25) with a predetermined carrier is supplied to a light transmitting element group provided in the terminal device 6. It is obtained by this. The carrier frequency used here is the same as that used for the communication path A described above.

The optical signal used for the communication path D is received by at least one of the light receiving element groups of the relay device 4A, and all the modulated signals obtained by frequency-converting the received carrier frequency modulation signal are supplied to the light transmitting element group of the relay device 4A. It is obtained by doing. The carrier frequency used here is the same as that used for the communication path B described above.

Thus, the communication paths A and B, which are downlinks,
The reason why the respective carrier frequency values f1 and f2 are not the same is that the optical signal transmitted by the relay device 4 is not received by itself and self-oscillation does not occur. During data distribution, the relay device 4A receives only the optical signal downlinked from the concentrator / distributor 3A, and the terminal device 6 receives only the optical signal downlinked from the relay device 4A.

Further, the reason why the carrier frequencies of the communication paths C and D, which are uplinks, are not the same is also the same. During data collection, the relay device 4 receives an optical signal to be uplinked from the terminal device 6. , Collection and distribution device 3A is a relay device
Receive the optical signal to be uplinked from 4A.

Note that the reason why the carrier frequency values f1 and f2 may be in a multiplying relationship is that they are relayed by optical radio, and radio waves in a multiplying relationship interfere with each other, whereas This is because the light signal does not interfere. Therefore, since the frequency can be converted by the multiplying circuit, the frequency converting circuit of the relay device can be easily configured.

As described above, the sub-collection / distribution device 3B is connected to the repeater 5
Is connected to the master collection / distribution device 3A. The connection line TA, which is an optical fiber, is connected between the master collection and distribution device 3A and the repeater 5, and the connection line TB, which is an optical fiber, is connected between the repeater 5 and the sub collection and distribution device 3B. Is sent and received.

The sub-collector / distributor 3B performs data collection / distribution with the master concentrator / distributor 3A via the code repeater 5 by optical signals via the connection lines TA and TB, and a plurality of repeaters 4Bl to 4Bn (in FIG. Data collection and distribution to and from the two relay devices 4B are performed via communication paths E and H, which are optical wireless communication paths.
The relay device 4B performs data collection and distribution between the terminal devices 6 (6B1 to 6Bn) via communication paths F and G, which are optical wireless communication paths.

The communication paths E and F are downlinks, and data distribution is performed using the downlinks. The communication paths G and H are uplinks, and data collection is performed using the uplinks.

Distribution of data is performed by the centralized information processing device P → control device 2 →
Connection line S → Master concentrator 3A → Connection line TA (optical cable) →
Repeater 5 → connection line TB (optical cable) → sub-collector / distributor 3B → communication path E (optical wireless) → repeater 4B → communication path F (optical wireless) →
This is performed via the path of the terminal device 6 (6B1 to 6Bn).

The data collection is performed by the terminal device 6 (6B1 to 6Bn) → communication path G (optical radio) → relay device 4B → communication path H (optical radio) →
Via the path of the sub concentrator / distributor 3B → connection line TB (optical cable) → repeater 5 → connection line TA (optical cable) → master concentrator / distributor 3A → connection line S → control device 2 → centralized information processing device P Done.

The optical signal for optical radio used for the communication path E is the same as that of the communication path A, and the optical signal for optical radio used for the communication path F is the same as that of the communication path B. The optical signal for optical wireless used in the communication path G is the same as that of the communication path C, and the optical signal for optical wireless used in the communication path H is the same as that of the communication path D.

The above-described repeater 5 operates the master concentrator / distributor 3A so that the phase of the optical signal distributed from the sub-concentrator / distributor 3B is the same as the phase of the optical signal distributed from the master concentrator / distributor 3A.
It adjusts the phase of the data signal (optical signal) supplied from the to the sub-collection / distribution device 3B. That is, since the master collection and distribution device 3A and the sub collection and distribution device 3B are separated,
The phase of the optical signal emitted from the sub-collection / distribution device 3B is relatively delayed with respect to the phase of the optical signal emitted from the master collection / distribution device 3A, and in the worst case, the two have an opposite phase relationship.

When this relationship is reached, both optical signals are canceled out,
This optical signal cannot be transmitted to the repeaters 4A and 4B. In order to prevent this, the repeater 5 adjusts the phase of the optical signal supplied from the master concentrator / distributor 3A via the connection line TA, amplifies it, and sends it to the sub-concentrator / distributor 3B via the connection line TB. By doing so, the phase of the optical signal emitted from the sub-concentration and distribution device 3B is made the same as the phase of the optical signal emitted from the master collection and distribution device 3A.

Next, the configurations of the light transmitting and receiving units of the collecting and distributing device and the relay device will be described in detail. The collecting and distributing device 3 (3A, 3B) and the relay device 4 (4A, 4B) are optical transmitting and receiving devices having light transmitting and receiving units of substantially the same shape. FIG. 2 is a sectional view of a base portion of the optical transceiver.

The base unit 7 of the optical transmitting / receiving device includes a light transmitting / receiving unit 8 in which a light transmitting / receiving substrate is housed, supporting parts 9A and 9B for supporting the light transmitting / receiving unit 8, a dust cover 10 covering the light transmitting / receiving unit 8, a signal processing unit (not shown) It is a disk-shaped device composed of a power supply unit and the like. The light transmitting / receiving unit 8 includes a light transmitting unit 12 opposed to the light shielding plate 11.
And a light receiving unit 13.

The light transmission unit 12 includes a plurality of light emitting diodes (LEDs)
The light transmitting unit 12 is integrally formed with the light shielding plate 11 and the light receiving unit 13 via the heat conductive sheet 15.

The light receiving unit 13 includes a plurality of pin photodiodes (PP
D) comprises a ring-shaped light receiving substrate 16 (see FIG. 4) and the like. Below the light receiving unit 13, a ring-shaped visible light cut filter 17 covering the pin photodiode is mounted.

Next, the light transmitting substrate 14 of the light transmitting unit 12 will be described in detail. FIG. 3 is a plan view for explaining the arrangement of light emitting diodes (LEDs) on the light transmitting substrate 14. FIG. The light transmitting board 14 is a printed board in which a hole through which a wiring material is inserted is formed in the center, and a plurality of light emitting diodes are arranged in a ring at a peripheral portion thereof so that light is emitted by a driver circuit (not shown). Have been.

The light emitting diodes are arranged at an angular interval smaller than a half-value angle (a light emitting angle at which the amount of emitted light is halved), and are configured so that the amounts of light emitted from light emitting diodes adjacent to each other are added. Accordingly, the overall directional characteristics (horizontal direction) emitted from the light transmitting substrate 14 are as shown by the solid line in the drawing.
As a whole, light is emitted over a wide range of 360 ° in the horizontal direction.

Next, the light receiving substrate 16 of the light receiving unit 13 will be described in detail. Fig. 4 shows the pin photodiode (PP
It is a bottom view explaining arrangement of D). The light receiving substrate 16 is a printed circuit board in which a hole through which a wiring material is inserted is formed in the center,
A plurality of pin photodiodes are annularly arranged on the periphery, and are connected to a signal processing circuit (not shown).

The pin photodiodes are arranged at intervals smaller than the half-value angle in the horizontal direction (the light receiving angle at which the amount of received light is halved).
The entire directional characteristic received by the light guide 16 is configured as shown by the solid line in the figure. Therefore, light can be received over a wide range of 360 ° without having a dead point (blind spot).

Light emitting diodes (LEDs) and pin photodiodes (PPDs) are partially arranged in a semicircular shape (180 degrees) or an arc shape instead of a 360-degree full circumference (see FIGS. 3 and 4). May be.

Next, the mounting relationship (angle) between the light emitting diode of the light transmitting substrate 14, the light receiving substrate 16, and the pin photodiode will be described.

As shown in FIGS. 2 to 4, the arrangement radius _RL of the light emitting diodes of the light transmitting substrate 14 (the light transmitting unit 12) is
Arrangement radius of pin photodiode of (light receiving unit 13)
Greater than R _P, and the light-receiving substrate 16 (light receiving unit 13) is disposed on the lower side of the light-sending substrate 14 (light-sending unit 12).

The light emitting diodes of the light transmitting substrate 14 are mounted such that the light transmitting direction (directivity) is substantially horizontal.
The pin photodiodes of the light receiving substrate 16 are mounted such that the light receiving direction (directivity) is directed obliquely downward from the horizontal direction.

Further, the light shielding plate 11 is a circular metal body interposed between the light transmitting unit 12 (the light emitting diode of the light transmitting substrate 14) and the light receiving unit 13 (the pin photodiode of the light receiving substrate 16). The outer periphery of the light-shielding plate 11 is an umbrella body 11A inclined obliquely downward from the horizontal direction.

The light shielding plate 11 allows the light emitting diode (LED) of the light transmitting unit 12 and the pin photodiode (P
Since the light from the light emitting diode is optically separated from the PD, the light from the light emitting diode does not reach the own pin photodiode and the pin photodiode is not saturated. That is, while the horizontal light emitting range emitted from the light transmitting unit 12 (light transmitting substrate 14) is omnidirectional as a whole by a plurality of light emitting diodes, the vertical light emitting range is individual light emitting range. The light-emitting unit 12 and the light-receiving unit 13 are integrated at different positions (heights) in the vertical direction with the light-shielding plate 11 interposed therebetween. The light emitting diode (LED) and the pin photodiode (PPD) of the light receiving unit 13 are optically separated. As a result, as in the above-described relay device 4, the received and input weak optical signal (modulated signal) is frequency-converted (multiplied by the carrier frequency), amplified, and transmitted.
Even in the case of output, the input and output do not combine and oscillate, and the relay operation is not disabled.

Further, the light-transmitting substrate 14 of the light-transmitting unit 12 and the light-receiving substrate 16 of the light-receiving unit 13 are also electrically (electromagnetically) shielded by the metallic light-shielding plate 11, so that the light-emitting diodes of the light-transmitting unit 12 The light receiving unit 13 does not malfunction due to unnecessary radiation.

In this way, the light transmitting unit 12 and the light receiving unit 13 can be arranged close to each other to integrate them, and the device can be downsized.

Further, a heat conductive sheet 15 (see FIG. 2) is mounted between the light shielding plate 11 and the light transmitting substrate 14 of the light transmitting unit 12, and the heat generated by the light emission of many light emitting diodes is → Light transmitting substrate 14 → Heat conductive sheet 15 → Light shield plate 11
And the heat is efficiently radiated from the metallic light-shielding plate 11.
Therefore, the output of the light emitting diode does not decrease or break down due to heat storage.

Next, the dust cover 10 and the visible light cut filter 17 will be described.

As shown in FIG. 2, an annular visible light cut filter
17 is a light receiving unit with a pin photodiode
It is a small one placed on the inner (circumferential) side to cover only 13. On the other hand, the frustoconical dust cover 10 is disposed on the outer (circumferential) side so as to cover the entire light transmitting and receiving unit 8 including the light transmitting unit 12, the light receiving unit 13, the visible light cut filter 17, and the like.

Further, as shown in FIG. 5, the dust cover 10 has a high light transmittance in a transmission wavelength band of optical wireless, and has a medium light transmittance in a visible light wavelength band outside the transmission wavelength band.
As described above, since the dust cover 10 has a medium light transmittance in the visible light wavelength band, the visible light is appropriately transmitted, and there is no visually strange feeling. On the other hand, visible light cut filter
Reference numeral 17 is a black color having a high light transmittance in the transmission wavelength band and blocking transmission in a visible light wavelength band outside the transmission wavelength band.

With the above configuration, harmful noise from fluorescent lamps and televisions is physically cut by the visible light cut filter 17 and is not input to the pin photodiode.
The light receiving unit 13 does not malfunction due to noise. Further, since the dust cover 10 is provided, no dust or the like enters the light transmitting / receiving unit 8 to cause a failure, and the dust cover 10 does not hinder the light transmission by the light transmitting unit 12.

Further, since the dust cover 10 is provided on the outer (peripheral) side of the visible light cut filter 17, the black visible light cut filter 17 itself is not directly seen, so that there is no strange feeling and the appearance is excellent.

Next, the structure of the terminal device 6 will be described. 6 (A) and 6 (B) are perspective views showing a terminal device.

In the figure, reference numeral 18 denotes an electric board of the terminal device 6, and 19 denotes a light transmitting / receiving board. The electric board 18 is a metallic shield case 21
Is housed inside. The light transmitting / receiving substrate 19 is a substrate provided with a plurality of light emitting diodes (LEDs) and one pin photodiode (PPD). The mounting surface of the light emitting diodes and the pin photodiode is exposed from one surface of the shield case 21. I have.

A plurality of wiring members 22 protrude from the light transmitting / receiving substrate 19 in parallel with the substrate surface, and the wiring members 22 are soldered to the printed hole groups (23 or 24) of the electric board 18 to transmit and receive light. The board 19 is configured to be electrically and mechanically connected to the electric board 18.

In the electric board 18 of the terminal device 6, a group of printed holes 23 arranged side by side substantially in parallel with the light transmitting / receiving
And a print hole group 24 arranged side by side so as to be inclined with respect to the opened light transmitting / receiving surface 20. Print hole group
23 and the printed hole group 24 are identical in terms of electric circuit.

Therefore, as shown in FIG. 6 (A), the wiring member 22 of the light transmitting / receiving substrate 19 is fixed to the printed hole group 24 by soldering, so that a vertical mounting type is obtained (first mounting position).
As shown in FIG. 7A, the terminal device 6 can be installed in the vertical direction beside the main device (for example, vending machine) 25. At this time, as shown in FIG. 8 (A), the light transmitting / receiving substrate 19 is installed in a vertical direction and is inclined upward, so that it is installed on another main device or incorporated in a ceiling. The relay device 4 at a higher position than the terminal device 6
The transmission and reception of light is effectively performed between the two.

Also, as shown in FIG. 6 (B), the wiring member 22 of the light transmitting / receiving substrate 19 is fixed to the printed hole group 23 by soldering, whereby a horizontal mounting type is obtained (second mounting position), and FIG. The terminal device 6 can be installed horizontally on the main device 25 as shown in FIG. At this time, FIG.
As shown in the figure, the light transmitting / receiving substrate 19 is installed in a horizontal direction and is inclined upward, and is installed on other main equipment or incorporated in the ceiling and is located at a position higher than the terminal device 6. Optical transmission / reception with a certain relay device 4 is effectively performed.

In this way, by fixing the light transmitting / receiving substrate 19 by soldering, the terminal device 6 can be either a vertical installation type or a horizontal installation type, so that there are few restrictions on the installation location and the installation position of the terminal device 6.

(Effects of the Invention) According to the optical wireless system according to the present invention, since the relay device relays the optical communication between the collecting and distributing device and the terminal device, the optical wireless system is distributed and arranged at an arbitrary place in a specific area. Data can be efficiently transmitted to and from a terminal device that has been used, and a terminal device or the like can be expanded or reduced according to the increase or decrease in the terminal device, so that a data transmission system of a desired scale can be easily constructed. When the distances between the concentrators are large, the optical signal emitted from one concentrator and the receiver is relatively delayed with respect to the phase of the optical signal emitted from the other concentrator. In the case where the signals have opposite phases between the distribution apparatuses, the signals are canceled out, so that an effect of preventing the optical signal from being transmitted to the relay apparatus can be prevented by the repeater.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of an optical wireless system according to the present invention, FIG. 2 is a cross-sectional view showing a base unit (transmitting / receiving unit) of a concentrator / distributor and a relay device constituting the optical wireless system, 3
FIG. 4 is a plan view showing a light emitting substrate of a light transmitting and receiving unit, FIG. 4 is a bottom view showing a light receiving substrate of the light transmitting and receiving unit, FIG. 5 is a diagram showing optical characteristics of a dust cover and a visible light cut filter, and FIG. 7A and 7B show a terminal device, FIGS. 7A and 7B show an example of installation of a terminal device, and FIGS. 8A and 8B show an example of installation of a terminal device. FIGS. 9 (A) and 9 (B) are views for explaining a conventional example. DESCRIPTION OF SYMBOLS 1 ... Optical wireless system, 2 ... Control device, 3 ... Concentrator / distributor, 3A ... Master concentrator / distributor, 3B ... Sub concentrator / distributor, 4 (4A, 4B) ... Relay device, 5 ... Repeater, 6 (6Al
~ 6An, 6Al ~ 6Bn) Terminal device 7, Base body 8,
Transmitter / receiver, 9A, 9B ... Support, 10 ... Dust cover, 11
… Shield plate, 12… Light transmitting unit, 13… Light receiving unit, 14… Light emitting substrate, 15… Thermal conductive sheet, 16… Light receiving substrate, 17… Visible light cut filter, 18… Electric substrate ,
19 ... Transmitter / receiver board, 20 ... Transmitter / receiver surface, 21 ... Shield case, 22 ... Wiring material, 23 ... Printed hole group, 24 ... Printed hole group, 25 ... Main device, P ... Concentrated Information processing equipment,
LED: Light emitting element (light emitting diode), PPD: Light receiving element (pin photodiode).

──────────────────────────────────────────────────続 き Continuing on the front page (72) Yoshiaki Yuzuki, Inventor 3--12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Japan (72) Inventor Tetsuro Fukazawa 3-12 Moriyacho, Kanagawa-ku, Yokohama, Kanagawa Address Japan Victor Company, Ltd. (72) Inventor Susumu Katayama 3-12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Japan Victor Company Ltd. (72) Inventor Akio Yoshikawa 1-26-5 Toranomon, Minato-ku, Tokyo Inside NTT Data Communication Co., Ltd. (72) Inventor Keishi Ushijima 1-26-5 Toranomon, Minato-ku, Tokyo NTT Data Communication Co., Ltd. (72) Invention Person Takaaki Takeda 1-26-5 Toranomon, Minato-ku, Tokyo NTT Data Communications Co., Ltd. (72) Inventor Ken Nomoto Torano, Minato-ku, Tokyo Examiner, NTT Data Communications Co., Ltd., 1-26-5 Shiro Wada (56) References JP-A-58-108839 (JP, A) JP-A-63-275231 (JP, A ) Hikaru Hei 2-82143 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) H04B 10/00-10/28

Claims (3)

(57) [Claims] A centralized information processing device, a plurality of centralized information distribution devices that perform data transmission with the centralized information processing device, and perform data collection and distribution with a relay device using optical wireless; And one or more relay devices for relaying and transmitting data to and from a terminal using optical wireless, and one or more terminal devices for transmitting data via the concentrator and the relay device; An optical wireless system characterized by interposing a repeater for synchronizing transmission data between a plurality of concentrators. 2. The collecting and distributing device and the relay device have a light transmitting and receiving unit in which a light emitting element and a light receiving element are arranged on an outer peripheral portion, and a height which is a ground level of the collecting and distributing device and the relay device. 2. The optical wireless system according to claim 1, wherein the terminal device arranged at a position has a transmitting / receiving board on which a light emitting element and a light receiving element are arranged and which is fixed at an angle. 3. A transmission / reception board of a terminal device, comprising: a first group of printed holes continuously provided in parallel with the housing surface; and a second group of printed holes continuously provided inclining on the housing surface. 3. The optical wireless system according to claim 2, wherein a light transmitting / receiving substrate is fixed to said first printed hole group or said second printed hole group.