JP3795870B2 - Optical space transmission system, optical information transmitter, optical information receiver, and optical space transmission control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical space transmission system, an optical information transmission device, an optical information reception device, and an optical space transmission control method for performing optical space transmission of information using LED light, and more particularly to LED illumination (light emitting device) in an optical space. It relates to technology shared for transmission.
[0002]
[Prior art]
As an optical space transmission device for transmitting information to free space using light, devices using infrared rays and devices using visible light of LEDs have been proposed (see Patent Documents 1 and 2).
[0003]
All of these use illumination as an optical space transmission device. For example, Patent Document 1 discloses an optical space transmission device that incorporates an infrared light emitting element in a fluorescent tube installed on a ceiling and transmits information by infrared rays. Patent Document 2 discloses an optical space transmission device that transmits information using LEDs.
[0004]
This type of optical space transmission device has a feature that a plurality of reception devices can simultaneously receive information because information can be transmitted in a range where light from a light source can reach. Further, since the light from the light emitting source is used as a carrier wave, it is not necessary to separately provide a carrier signal for information transmission, and an antenna is not required, so that the entire apparatus can be reduced in size and cost.
[0005]
[Patent Document 1]
JP-A-6-37720
[Patent Document 2]
JP 2002-290335 A
[0006]
[Problems to be solved by the invention]
However, the conventional optical space transmission device only transmits information unilaterally from the light source, and cannot transmit information corresponding to the characteristics of the receiving device that receives the information from the light source. For this reason, when a plurality of receiving devices exist within the range where the light from the light emitting source reaches, there is a risk that some receiving devices may not be able to receive information normally.
[0007]
The present invention has been made in view of such a point, and the object thereof is an optical space transmission system, an optical information transmission device, and an optical information transmission device capable of performing highly reliable optical space transmission in accordance with the characteristics of each receiving device. An optical information receiving apparatus and an optical space transmission control method are provided.
[0008]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides an optical space transmission system including a light emitting device that emits LED light and a receiving device that receives the LED light. A light emitting means for emitting LED light; and a control information communication means for transmitting and receiving the light reception control information of the LED light with a transmission path different from the LED light, and the receiving apparatus is configured to emit the light emission. Light receiving means for receiving the LED light emitted by the means, and control information communication means for transmitting and receiving the light reception control information through the separate transmission path.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an optical space transmission system, an optical information transmission device, an optical information reception device, and an optical space transmission control method according to the present invention will be specifically described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of an embodiment of an optical space transmission system according to the present invention. The space optical transmission system of FIG. 1 includes a transmission device 1 that transmits information using LED illumination light, an LED light-emitting device 2 with a control function that transmits information on LED illumination light, and information by LED illumination light. And a receiving device 3 that receives the transmission.
[0010]
The LED light emitting device 2 is a light source for illumination, and also has a function of transmitting information by modulating a power waveform supplied to the light source for illumination. The LED light-emitting device 2 includes a light-emitting source 4 that emits LED illumination light, a control unit 5 that optically modulates information transmitted from the transmission device 1, and an infrared communication unit 6 that transmits and receives control information by infrared rays to and from the reception device 3. Have.
[0011]
According to one aspect of the present invention, the working unit having at least two degrees of freedom and contacting the work target, the first operation unit that can be grasped by the operator, and the two-degree-of-freedom direction of the working unit A second operation unit for controlling the operation of each of the second operation units, each of which is capable of controlling the operation of the working unit in at least one direction of the two degrees of freedom. There is provided a medical manipulator having first and second switches for performing an operation with a finger of a hand held by a person.
[0012]
Here, the control information is, for example, light reception control information of the receiving device 3 (for example, information such as luminance, illuminance, and direction of received LED illumination light). Device information of the receiving device 3 may be transmitted as control information.
[0013]
More specifically, the control unit 5 has an internal configuration as shown in FIG. 2, and includes a modulator 7 that supplies a power waveform modulated in accordance with information transmitted from the transmission device 1 to the light emission source 4, and the transmission device 1. And a device list 8 in which information of the receiver 3 capable of receiving LED illumination light is registered, a switch 9 for turning on / off the power supplied from the commercial power supply PW, a control of the modulator 7 and the switch 9, and a device list 8 CPU 10 for performing registration and deletion.
[0014]
For the device list 8, registration, reference, deletion, and other necessary operations are performed at the start of communication, during communication, and at the end of communication. The device list does not necessarily exist in the control unit 5 of the LED light emitting device 2. For example, the device list is communicated with the receiving device 3 in the transmitting device 1 that can communicate with infrared rays, or from the transmitting device 1 or the LED light emitting device 2. It may exist on the network as a possible controller alone.
[0015]
The receiving device 3 includes a light receiving unit 11 that receives the LED illumination light transmitted from the LED light emitting device 2, a demodulator 12 that demodulates the received LED illumination light and restores the original information, and the LED light emitting device 2. On the other hand, it has the infrared communication part 13 which transmits / receives control information by infrared rays.
[0016]
Infrared rays may be transmitted from the receiving device 3 to the LED light emitting device 2 only in one direction, or may be transmitted and received bidirectionally between the receiving device 3 and the LED light emitting device 2. When transmission / reception can be performed in both directions, the reception device 3 can receive a response signal, a notification signal, and the like from the LED light-emitting device 2 using infrared rays.
[0017]
When transmitting control information by infrared rays, infrared rays modulated by the control information are also transmitted. The modulation method is not particularly limited. For example, an intensity modulation direct detection method using an NRZ code is used.
[0018]
The device list 8 in the LED light emitting device 2 registers information on LED lighting (LED light emitting device), information on the receiving device 3 that receives LED illumination light, and information on the transmitting device 1. The information registered in the device list 8 is referred to by the CPU 10 at the start of communication with the receiving device 3, during communication, and at the end of communication.
[0019]
The device list 8 is not necessarily provided in the LED light emitting device 2, and may be provided, for example, in the transmission device 1 or on a network (not shown) connected to the transmission device 1 or the LED light emitting device 2. It may be provided.
[0020]
FIG. 3 is a diagram showing an example of information registered in the device list 8. As illustrated, in the device list 8, (1) a list related to the LED lighting (LED light emitting device) 2, (2) a list related to the receiving device 3, and (3) a list related to the transmitting device 1 are registered.
[0021]
(1) The LED lighting (LED light emitting device) list is more specifically an ID for identifying individual LED lighting (LED light emitting device), and an ID for identifying the transmitting device 1 that has transmitted the information included in the LED lighting light. The channel number used for optical space transmission and the last communication time are included. Note that these are not essential information, and at least some of the information may be changed as necessary.
[0022]
(2) The list relating to the receiving device 3 includes an ID for identifying the receiving device 3, an ID for identifying the received LED illumination (LED light emitting device), and various information relating to the receiving device 3 (device identification information such as a printer, manufacturing) Device number such as a number, compatible software, light receiving sensitivity, etc.) and information for identifying fixed registration / temporary registration (temporary registration is deleted from the device list 8 when communication is not performed for a certain period of time. On the other hand, the fixed registration is not deleted from the device list 8 regardless of whether communication is performed or not.For example, a device such as a printer that does not move so much may be fixedly registered by default) and the corresponding LED emission It includes an ID for identifying the device 2, encryption information (the presence or absence of encryption, a key for encryption and other parameters), and the last communication time.
[0023]
(3) The list relating to the transmission device 1 includes an ID for identifying the transmission device 1, the type of the reception device 3 that is a transmission partner, the amount of information to be transmitted, an outline of transmission contents, and instruction information for LED illumination light ( For example, “Send information with a red LED” or “Let the illuminance be less than or equal to XX lux”), encryption information (whether encryption is used, encryption key or other parameters), And the time when the information was last communicated.
[0024]
The network based on the optical space transmission system of FIG. 1 may be connected to other networks (for example, home appliance network such as Echonet, AV network, and LAN) to increase the scale of the network.
[0025]
When the network based on the optical space transmission system in FIG. 1 is connected to a home appliance network or the like, the LED light-emitting device 2 and the receiving device 3 are not only on / off indicating the use state as illumination as the LED illumination light status display, It is desirable to display an indicator (for example, during information transmission / reception) indicating a usage state as a communication device on the display unit. Thereby, the following unexpected situations can be avoided.
[0026]
That is, in an optical space transmission system using LED illumination light alone, when the switch of the LED light emitting device 2 is physically turned off, the communication path is cut off even during information transmission / reception, and transmission / reception is interrupted. However, when the LED light-emitting device 2 is connected to the home appliance network and the LED illumination light is controlled from the home appliance network control device, the power cannot be turned off when the status display of the LED light-emitting device 2 is “information transmitting / receiving”. Can be set. In this way, it is possible to avoid interruption of transmission / reception caused by accidentally turning off the power of the LED light emitting device 2.
[0027]
A processing procedure for controlling the power supply of the LED light emitting device 2 is represented by a flowchart as shown in FIG. This flowchart is performed by the CPU 10 in the LED light emitting device 2, for example.
[0028]
First, when a power-off command for the LED light emitting device 2 is received (step S1), it is determined whether information is currently being transmitted to the receiving device 3 (step S2). If information is being transmitted, a response indicating that the LED light emitting device 2 cannot be turned off is returned (step S3). In this step S3, for example, a display device (not shown) of the LED light emitting device 2 displays that the LED light emitting device 2 cannot be turned off. On the other hand, if the information is not being transmitted, the power source of the LED light emitting device 2 is turned off (step S4). In this case, the emission of the LED illumination light is stopped.
[0029]
Next, a communication control procedure of the transmission device 1, the LED light emitting device 2, and the reception device 3 will be described in detail. The communication control procedure includes a communication link establishment procedure and an established communication link cancellation procedure, and a plurality of methods can be considered for both procedures. Hereinafter, it demonstrates in order.
[0030]
(First communication link establishment procedure)
FIG. 5 is a sequence diagram of the first communication link establishment procedure. The transmitting device 1 registers its own device in the device list 8 of the LED light emitting device 2 before transmitting information to the receiving device 3 (step S11). Next, the transmitting device 1 polls the LED light emitting device 2 at a predetermined default frequency (calling to the receiving device 3) in order to search whether there is a receiving device 3 that receives information. Alternatively, broadcast communication is performed for an unspecified number of receiving devices 3 (step S12).
[0031]
Items notified to the receiving device 3 at the time of polling are items described in the transmitting device 1 of the device list 8, for example. The polling is not necessarily performed by the LED illumination light, but may be performed by a downlink for control by infrared rays.
[0032]
In response to this polling, when a certain receiving device 3 requests registration of the LED light emitting device 2 to the device list 8 by infrared rays (step S13), the LED light emitting device 2 is based on the control information transmitted from the receiving device 3. Whether registration is possible or not is determined, and if registered, an acknowledge signal is transmitted to the receiver 3 by LED illumination light or infrared rays (step S14).
[0033]
Thereafter, the transmitting device 1 transmits information to the LED light emitting device 2, and the LED light emitting device 2 transmits the LED illumination light modulated by this information to the receiving device 3 (step S15).
[0034]
(Second communication link establishment procedure)
The first communication link establishment procedure is performed at an arbitrary timing (for example, when the transmission device 1 is registered and the transmission is started), whereas the LED light emitting device 2 is connected to the reception device 3. During the information transmission, the receiving device 3 may be periodically polled for the receiving device 3 newly entering the receivable range. This is the second communication link establishment procedure, and its sequence diagram is as shown in FIG.
[0035]
In the sequence diagram of FIG. 6, when there are a plurality of receiving devices 3 a and 3 b, the receiving device 3 a is already receiving information, so polling is ignored, and only the receiving device 3 b responds to the polling of the LED light emitting device 2. An example in which registration is performed in the device list 8 of the LED light emitting device 2 is shown. (Step S24).
[0036]
In this case as well, polling may be performed using an infrared downlink instead of LED illumination light.
[0037]
(Third communication link establishment procedure)
In the third communication link establishment procedure, the LED light emitting device 2 starts polling and registers the receiving device 3 in advance even if there is no transmitting device 1 that desires to transmit information.
[0038]
FIG. 7 is a sequence diagram of a third communication link establishment procedure. First, the LED light emitting device 2 starts polling (step S31), and when the receiving device 3 that desires to receive requests registration to the device list 8 via infrared rays (step S32), it checks whether registration is possible and registers it. An acknowledge signal is transmitted to the receiving device 3 that has acknowledged (step S33).
[0039]
Thereafter, the transmission device 1 requests registration of the LED light-emitting device 2 to the device list 8, and when the registration is completed (step S34), the LED light-emitting device 2 informs the reception device 3 that the transmission device 1 has been registered. Notification is made (step S35). When the receiving device 3 responds to this notification (step S36), the LED light emitting device 2 modulates the LED light with the information transmitted by the transmitting device 1 and performs optical space transmission to the transmitting device 1 (step S37). .
[0040]
As an example of the third communication link establishment procedure, the LED light emitting device 2 may perform polling when the LED power is turned on and the LED illumination light is turned on.
[0041]
(Fourth communication link establishment procedure)
The fourth communication link establishment procedure notifies the LED light emitting device 2 of various information to be registered in the device list 8 by the receiving device 3 at an arbitrary timing without waiting for polling of the LED light emitting device 2 and the transmitting device 1. )
[0042]
FIG. 8 is a sequence diagram of the fourth communication link establishment procedure. First, the transmission device 1 requests registration of the LED light emitting device 2 to the device list 8 (step S41). The receiving device 3 also requests registration of the LED light emitting device 2 in the device list 8 (step S42). In response to this registration request, the LED light-emitting device 2 receives various information (information transmitted at the time of polling and basic information other than information transmitted to the unspecified majority by the default frequency) from the LED light-emitting device 2. (Same as above) is transmitted to the receiving device 3 (step S43).
[0043]
The receiving device 3 that has received the information from the LED light emitting device 2 transmits an acknowledge signal to the LED light emitting device 2 (step S44), and a communication link is established between the receiving device 3 and the LED light emitting device 2. .
[0044]
Thereafter, LED illumination light modulated by the information from the transmission device 1 is emitted from the LED light emitting device 2, and optical space transmission to the reception device 3 is performed (step S45).
[0045]
(Fifth communication link establishment procedure)
In the fifth communication link establishment procedure, the reception device 3 makes a registration request to the device list 8 of the LED light-emitting device 2 with the time when the LED light-emitting device 2 starts emitting the LED illumination light as a trigger.
[0046]
In this case, the receiving device 3 includes an optical sensor that detects light emission of the LED illumination light. FIG. 9 is a sequence diagram of the fifth communication link establishment procedure. When the LED light emitting device 2 starts light emission of LED illumination light (step S51) and the reception device 3 detects light emission of LED illumination light by an optical sensor or the like, the reception device 3 registers in the device list 8 of the LED light emission device 2. A request is made (step S52).
[0047]
Note that if the light sensor of the receiving device 3 is in the power-off state, the light emission of the LED illumination light cannot be detected, and therefore it is necessary to always turn on the light sensor.
[0048]
Next, the LED light emitting device 2 sends a response (acknowledge) to the effect that the reception device 3 has been registered to the reception device 3 (step S53).
[0049]
Thereafter, when the transmitting device 1 makes a registration request to the LED light emitting device 2 (step S54), the LED light emitting device notifies the receiving device 3 that the transmitting device 1 has been registered (step S55). When the receiving device 3 returns an acknowledge signal in response to this notification (step S56), the LED light emitting device 2 emits the LED illumination light modulated by the information from the transmitting device 1, and the light space to the receiving device 3 is reached. Transmission is performed (step S57).
[0050]
Note that a light source that emits LED illumination light modulated by information from the transmission device 1 and a light source that simply emits LED illumination light for illumination purposes may be installed on the ceiling surface of the room. . For this reason, when the receiving device 3 does not receive a response or registration notification from the LED light emitting device 2 within a predetermined time, the receiving device 3 determines that the LED illumination light applied to the LED 3 is not for information transmission. You may judge that.
[0051]
Next, a procedure for releasing a communication link once established will be described. A plurality of methods can be considered for the procedure for releasing the communication link. Hereinafter, these procedures will be described in order.
[0052]
(First communication link release procedure)
In the first communication link release procedure, the reception device 3 notifies the release of the communication link at an arbitrary timing.
[0053]
FIG. 10 is a sequence diagram of the first communication link release procedure. While the transmitting device 1 is transmitting information modulated into LED illumination light to the receiving device 3 via the LED light emitting device 2, or after the transfer is completed (step S61), the receiving device 3 emits LED light via infrared rays. When the registration cancellation is notified to the device 2 (step S62), the LED light emitting device 2 deletes the information regarding the receiving device 3 from the device list 8 to release the communication link, and responds to that effect to the LED light emitting device 2 (step S62). S63).
[0054]
(Second communication link release procedure)
In the second communication link cancellation procedure, the reception device 3 requests the LED light-emitting device 2 to delete the registration when the information transmission by the LED illumination light is not continuously performed for a predetermined period. In this case, the receiving device 3 includes an optical sensor that detects light emission / extinction of the LED illumination light.
[0055]
FIG. 11 is a sequence diagram of the second communication link release procedure. After the light emission of the LED illumination light whose information is modulated is finished (step S71), when the information transmission by the LED illumination light is not performed even after a predetermined period (step S72), the receiving device 3 transmits the information to the LED light emitting device 2. In response to the request, registration deletion from the device list 8 is requested (step S73). When the LED light-emitting device 2 deletes the registration from the device list 8 and cancels the communication link, the LED light-emitting device 2 notifies the receiving device 3 to that effect (step S74).
[0056]
As described above, if the receiving device 3 notifies the LED light emitting device 1 of the release of the communication link when the spatial light transmission by the LED illumination light is not performed for a certain period of time, the receiving device 3 When LED illumination light from another LED light emitting device can be received, a communication link can be established with the LED light emitting device.
[0057]
In steps S <b> 72 and S <b> 73 described above, the receiving device 3 may request registration deletion from the device list 8 when the emission of the LED illumination light stops without waiting for a predetermined period.
[0058]
(Third communication link release procedure)
In the third communication link release procedure, the LED light emitting device 2 periodically polls the receiving device 3 while the LED illumination light is emitted, and the receiving device 3 always responds to the polling. When there is no response from the receiving device 3, the LED light emitting device 2 deletes the registration of the receiving device 3.
[0059]
FIG. 12 is a sequence diagram of the third communication link release procedure. The LED light emitting device 2 emits LED illumination light including the modulation information transmitted by the transmission device 1 (step S81), and periodically polls the reception device 3 (step S82). This polling may be performed using LED illumination light or infrared rays.
[0060]
When the receiving device 3 responds to polling (step S83), the registration to the device list 8 is maintained, and for the receiving device 3 that has not made a response, it is determined that the receiving device 3 is not in a communicable state. And deleted from the device list 8.
[0061]
As another procedure for releasing the communication link, for example, a method in which the transmission device 1 or the LED light emitting device 2 notifies the release of the communication link at an arbitrary timing is also conceivable.
[0062]
(Authentication / Security)
When establishing the communication link described above, consideration for authentication and security is indispensable.
[0063]
FIG. 13 is a flowchart showing an example of an authentication / security procedure performed when the optical space transmission system of FIG. 1 establishes a communication link. First, the LED light emitting device 2 receives various information (light reception control information) related to the receiving device 3 transmitted by the receiving device 3 via infrared rays (step S91). Part or all of the received information is registered in the device list 8.
[0064]
Next, the LED light emitting device 2 compares various information regarding the receiving device 3 with preset conditions, and determines whether or not the communication link may be established (step S92). The determination criteria are, for example, only when the communication link is established only when the receiving device 3 is a printer, only when the communication link is established only with the receiving device 3 of a specific product number of a specific manufacturer, or when the light receiving sensitivity is more than a certain level. A standard for establishing a communication link.
[0065]
If it is determined that the communication link may be established, the LED light emitting device 2 determines the communication conditions such as the channel used and the presence / absence of encryption, and sets the communication link (step S93).
[0066]
When the communication link is set, the LED light emitting device 2 notifies the receiving device 3 of the ID of the LED illumination light, the communication condition, and the like (step S94). On the other hand, when it is not determined that the communication link may be established, the receiving apparatus 3 is notified that the communication link is not set (step S95).
[0067]
(Mapping between devices)
The range in which the LED illumination light can reach is a range where optical space transmission is possible, and the registration request should come only from the receiving device 3 within the communicable range. However, in the present embodiment, infrared communication is used for a registration request or the like, and in some cases, an infrared communication device located in a range where LED illumination light does not reach may make a registration request.
[0068]
In order to cope with such a situation, it is desirable to reduce the directivity of infrared communication so that infrared communication is possible only within the range where the LED illumination light can reach.
[0069]
In addition, a camera attached to the light source 4 that emits LED illumination light is used to photograph the receiver 3 within the light receiving range, and information obtained from the photographed image (for example, a barcode on a label attached to the receiver 3) The serial number, the shape and size of the receiving device 3) and the registration information transmitted from the receiving device 3 are checked to determine whether the receiving device 3 is correctly positioned within the light receiving range of the LED illumination light. May be.
[0070]
Alternatively, when the receiving device 3 is provided with a light sensor and a polling signal is received from the LED light emitting device 2, the light sensor first checks whether or not the device is within the light receiving range, and enters the registration procedure if confirmed. If it is not confirmed, it is possible to perform a procedure not to enter the registration procedure.
[0071]
(Communication procedure when multiple LED lights are present)
A device list 8 of a certain LED light-emitting device 2 so that a device such as a printer in an office rarely moves a location can receive only a predetermined LED illumination light even if it can communicate with a plurality of LED illumination lights. A fixed registration may be made. In such a case, the receiving device 3 that desires fixed registration may notify that a fixed registration is requested when requesting registration to the device list 8.
[0072]
On the other hand, communication devices that are easy to carry around, such as PCs and mobile phones, and are often used in mobile environments, use LED illumination light that they receive according to a preset communication LED illumination light selection procedure. Can be selected. As a method for selecting the LED illumination light, for example, the following (1) to (5) are conceivable.
[0073]
(1) Select the LED illumination light that has been polled first (including polling performed by the transmission device 1 via the LED light-emitting device 2).
(2) Select one of a plurality of LED illumination lights at random.
(3) Select the LED illumination light that has responded to the registration request message sent randomly by infrared without specifying the recipient.
(4) Select LED illumination light that meets the criteria for LED illumination light indicators specified in advance (regardless of the content of transmission information) such as color, brightness, and illuminance of the LED illumination light.
(5) The LED illumination light is selected based on the result of exchanging information with the individual LED light emitting devices 2 that emit the LED illumination light through infrared rays.
Alternatively, when a plurality of LED illumination lights and one or more receiving devices 3 can communicate with each other, the LED illumination has good communication conditions such as high brightness and illuminance, or low traffic and difficulty in blocking light. It is desirable to select light. On the other hand, when a plurality of LED illumination lights and one or more communication devices are not connected to each other, needless to say, the receiver 3 that can communicate is limited by the selected LED illumination light.
[0074]
(Data format of information transmitted by the transmission device 1 or the reception device 3)
When an image or character including red is displayed while receiving red LED illumination light, the reddish image or character becomes difficult to visually recognize. In addition, it is better to see business documents under bright white light. Or, when listening to healing music, it is better to reduce the brightness slightly.
[0075]
Taking this into consideration, the transmitter 1 that intends to transmit information using LED illumination light registers its own device in the device list 8 prior to information transmission for the LED illumination light used for transmission. When setting the parameters of light parameters such as the color and brightness of the LED illumination light, the time when the setting is valid (if it is after registration, it may be before or after sending information) It is also possible to specify the transmission channel to be used (for effective information when viewed under red illumination, the frequency band to be modulated, that is, the transmission channel is limited to red, etc.).
[0076]
Further, the transmission device 1 transmits parameter values such as the color and intensity of the LED illumination light and the time for enabling the setting to the LED light-emitting device 2 (if the transmission time is after registration, before transmitting information) However, it may be performed at the time of information transmission or after information transmission). Alternatively, the transmission apparatus 1 designates a transmission channel to be used in optical space transmission (for example, when the display is viewed under red illumination light, effective information is to limit the frequency band to be modulated, that is, the transmission channel to red, etc.) )
[0077]
In addition, the transmitting device 1 transmits the information itself for performing the optical space transmission by adding a parameter for specifying the LED illumination light and a field for specifying the transmission channel, not at the time of registration in the device list 8. The LED light emitting device 2 to be relayed may refer to this field and set as indicated.
[0078]
The data format of the registration request packet to the device list 8 transmitted from the transmitting device 1 to the LED light emitting device 2 is, for example, as shown in FIG. As illustrated, the registration request packet includes a destination, a transmission source, a packet type = registration, an ID of the transmission device 1, a type and size of the reception device 3, a registration information content, an LED illumination light luminance, an LED illumination light color, and the like. Consists of.
[0079]
On the other hand, FIG. 15 is a diagram showing a data format of a data packet transmitted from the transmission device 1 to the LED light emitting device 2. As shown in the figure, the data packet includes a destination, a transmission source, a packet type = data, a brightness of LED illumination light, a color of LED illumination light, a data body, and the like.
[0080]
As a result, when the receiving device 3 has a function of outputting information downloaded by LED illumination light (screen display, audio output, etc.), the physical information is received when a person receives (views, listens, etc.) the output of information contents. This makes it possible to select a color or light intensity that is highly effective mentally and psychologically.
[0081]
(Specific Embodiment of the Present Invention)
One implementation is an LED illumination light stand. Various information can be downloaded cordlessly if a PC or the like is placed within the irradiation range of the LED illumination light emitted from the stand. Moreover, since the transmission range of information coincides with the irradiation range of the LED illumination light, it is possible to grasp at a glance which range the information can be transmitted. Therefore, it is easier for the user to understand than infrared rays in which light cannot be seen.
[0082]
In addition, if this type of LED lighting stand is installed next to exhibits such as exhibitions, you can download explanations about the exhibits using an information terminal such as a mobile phone or PDA while viewing the exhibits. Visitors can easily obtain detailed information about exhibits.
[0083]
As another realization form, it is conceivable to incorporate the light emitting source 4 of the present embodiment in a lighting device for a ceiling in a room or a specific area. In this case, information required by a person in the room or the specific area can be provided in combination with a human sensor provided at the entrance of the room or the specific area.
[0084]
More specifically, for example, when a visitor brings a mobile phone with a built-in receiving device 3 close to the entrance of a party venue, the LED light emitting device 2 emits LED illumination light, and the LED illumination light is emitted. Possible triggers include polling and registration, and distributing lottery numbers to visitors' mobile phones. Alternatively, when a participant arrives at the entrance of the conference room, LED illumination light is automatically emitted, and this is used as a trigger between the receiving device 3 (for example, PC) possessed by the participant and the LED light emitting device 2. It is conceivable to establish a communication link and distribute the materials of the meeting for the day to the receiving device 3.
[0085]
In the above case, the trigger for establishing the communication link is when the human sensor (having the receiving device 3) senses that it has entered a predetermined area with the human sensor. The processing procedure of the optical space transmission system in this case is represented by a sequence diagram as shown in FIG.
[0086]
First, when the LED light emitting device 2 emits LED illumination light (step S101), the light emission of the LED illumination light is notified to the transmission device 1 (step S102). The receiving device 3 receives the LED illumination light (step S103) and detects that the LED illumination light is emitted.
[0087]
Next, each of the transmission device 1 and the reception device 3 requests registration from the LED light-emitting device 2 (steps S104 and S105). Alternatively, the LED light emitting device 2 may be requested to register in response to polling performed immediately after the LED illumination light is emitted. When the registration operation is completed, the reception device 3 notifies the reception device 3 of the completion of registration (step S106). When the reception device 3 responds to the notification (step S107), the transmission device 1 emits an LED. Information is transmitted to the receiving device 3 via the device 2 (step S108).
[0088]
As another embodiment of the present invention, information can be broadcast simultaneously in a range where LED illumination light can reach in a place where a large number of information devices such as offices exist. As a result, for example, software updates and version upgrades of all information devices can be performed simultaneously.
[0089]
As described above, in this embodiment, the LED light emitting device 2 not only performs the spatial light transmission by the LED illumination light to the receiving device 3 only in one direction, but the receiving device 3 transmits the infrared light to the LED light emitting device 2. Since the control information can be transmitted by the LED light emitting device 2, the LED light emitting device 2 can determine in advance whether or not the LED illumination light should be transmitted, and the LED lighting considering the characteristics and intentions of the receiving device 3 Light can be transmitted. Thereby, stable information transmission can be performed and security can be improved.
[0090]
In the above-described embodiment, an example in which control information is transmitted and received between the receiving device 3 and the LED light emitting device 2 by infrared rays separately from the LED illumination light has been described. However, a communication medium other than infrared rays (for example, radio waves or wired communication) Etc.) may be used to send and receive control information.
[0091]
【The invention's effect】
As described above in detail, according to the present invention, since the receiving device and the LED light emitting device communicate light reception control information through a transmission path different from the LED illumination light, the characteristics on the receiving device side are taken into consideration. Optical space transmission can be performed, and the reliability and security performance of optical space transmission can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing the overall configuration of an embodiment of an optical space transmission system according to the present invention.
FIG. 2 is a block diagram showing an internal configuration of a control unit.
FIG. 3 is a diagram showing an example of information registered in a device list.
FIG. 4 is a flowchart showing a processing procedure for performing power supply control of the LED light emitting device.
FIG. 5 is a sequence diagram of a first communication link establishment procedure.
FIG. 6 is a sequence diagram of a second communication link establishment procedure.
FIG. 7 is a sequence diagram of a third communication link establishment procedure.
FIG. 8 is a sequence diagram of a fourth communication link establishment procedure.
FIG. 9 is a sequence diagram of a fifth communication link establishment procedure.
FIG. 10 is a sequence diagram of a first communication link release procedure.
FIG. 11 is a sequence diagram of a second communication link release procedure.
FIG. 12 is a sequence diagram of a third communication link release procedure.
13 is a flowchart showing an example of an authentication / security procedure performed when the optical space transmission system of FIG. 1 establishes a communication link.
FIG. 14 is a diagram showing a data format of a registration request packet for a device list transmitted from the transmitting device to the LED light emitting device.
FIG. 15 is a view showing a data format of a data packet to a device list transmitted from the transmitting device to the LED light emitting device.
FIG. 16 is a flowchart showing an example of a specific implementation form of an optical space transmission system.
[Explanation of symbols]
1 Transmitter
2 LED light emitting device
3 Receiver
4 Light source
5 Control unit
6,13 Infrared communication part
9 switch
10 CPU
11 Light receiver
12 Demodulator

Claims (14)

In an optical space transmission system comprising a light emitting device that emits LED light and a receiving device that receives the LED light,
The light emitting device
An illumination light source that emits LED light that can change at least one of brightness, illuminance, and direction ;
Power waveform supplied to the illumination light source, a modulatable light emission control means in response to the transmission information,
Control information communication means for transmitting and receiving the light reception control information of the LED light exchanged with the receiving device in a transmission path different from the LED light,
The receiving device is:
A light receiving means for receiving LED light emitted from the illumination light source ;
Control information communication means for transmitting and receiving the light reception control information in the another transmission path ,
The light emission control means includes
A switch for switching whether to supply a power supply voltage to the illumination light source;
Information transmission determination means for determining whether or not information is being transmitted using the illumination light source when the switch off command is received;
An optical space transmission system comprising: a switch control unit that permits the switch to be turned off only when the information transmission determination unit determines that information is not being transmitted.   2. The optical space transmission system according to claim 1, further comprising registration means for registering the light reception control information received by the control information communication means.   3. The optical space transmission system according to claim 1, wherein the light reception control information includes at least one information of luminance, illuminance, and direction of the LED light received by the light receiving unit. Comprising a transmitter for modulating the LED light and transmitting information to be transmitted;
The optical space transmission system according to any one of claims 1 to 3, wherein the light-emitting device includes a light modulation unit that generates LED light modulated by information transmitted from the transmission device.   5. The optical space transmission system according to claim 4, wherein the illumination light source emits LED light modulated in response to a search response request in order to search for the communicable receiving device. The control information communication means of the receiving device that wishes to receive information from the transmitting device transmits the light reception control information in response to the LED light modulated by the search response request,
The illumination light source transmits LED light modulated with information instructed from the transmission device to the reception device after the control information communication means receives the light reception control information from the reception device. The optical space transmission system according to claim 5.   The illumination light source receives the light reception control information from the reception device without making a search response request to the reception device, and then converts the LED light modulated with the information instructed from the transmission device to the LED light. The optical space transmission system according to claim 4, wherein the optical space transmission system is transmitted to a receiving device.   The said receiving apparatus and the said transmission apparatus perform the process for establishing a communication link with the said light-emitting device by the opportunity that the said light source for illumination started emission of LED light. The described optical space transmission system.   9. The illumination light source emits LED light only to the receiving device that satisfies a predetermined light receiving condition based on the light receiving control information transmitted from the receiving device. An optical space transmission system according to any one of the above.   The optical space transmission system according to any one of claims 1 to 9, wherein the receiving device disconnects a communication link with the light emitting device when detecting the light emission stop of the light source for illumination.   The optical space transmission system according to any one of claims 4 to 10, wherein the receiving device has display means for visually displaying that information from the transmitting device has been received.   The optical transmission system according to claim 1, wherein the transmission path is a path for transmitting the light reception control information by infrared rays. An illumination light source that emits LED light that can change at least one of brightness, illuminance, and direction ;
Light emission control means capable of modulating a power waveform supplied to the illumination light source according to information to be transmitted;
Control information communication means for transmitting and receiving the light reception control information of the LED light exchanged with the receiving device that receives the LED light in a transmission path different from the LED light ,
The light emission control means includes
A switch for switching whether to supply a power supply voltage to the illumination light source;
Information transmission determination means for determining whether or not information is being transmitted using the illumination light source when the switch off command is received;
An optical information transmission apparatus comprising: a switch control unit that permits the switch to be turned off only when the information transmission determination unit determines that information is not being transmitted. In a light space transmission control method for performing light space transmission between a light emitting device that emits LED light and a receiving device that receives the LED light,
The light emitting device
LED light that can change at least one of brightness, illuminance, and direction is emitted from the illumination light source,
The power waveform supplied to the illumination light source is modulated by the light emission control means according to the information to be transmitted,
Send and receive the light reception control information of the LED light exchanged with the receiving device in a transmission path different from the LED light,
The receiving device is:
Receives LED light emitted by the illumination light source ,
Sending and receiving the light reception control information in the another transmission path ,
The light emission control means includes
Whether to supply a power supply voltage to the illumination light source connected to the power line is switched by a switch,
When receiving an off command of the switch, it is determined whether information is being transmitted using the illumination light source,
An optical space transmission control method characterized by permitting the switch to be turned off only when it is determined that information is not being transmitted.

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