JP4338387B2 - Visible light receiver and visible light communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to various signals that be transmitted by modulating the visible light in the visible light receiver and a visible light communication device.
[0002]
[Prior art]
Conventionally, invisible infrared light is used when performing wireless communication using light as a communication medium. The reason for this is that the transmission efficiency of infrared light transmitting devices and receiving devices is higher than that of visible light, and that using visible light is visually uncomfortable or obstructive to humans. . On the other hand, when visible light is used, since the receivable area can be visually recognized by a person, it is excellent in convenience, entertainment, and the like depending on the application. For example, when it is considered that two or more PCs (personal computers) are provided with light transmitters / receivers and face each other for communication, visible light is easier for users to place each PC.
[0003]
As a conventional example that enables the above arrangement, there is one disclosed in Patent Document 1, for example. In Patent Literature 1, a visible light LED that displays the status of an electronic device, an infrared LED that emits transmission light, and an optical guide that combines the emitted light of each of the visible light LED and the infrared LED are used. Both visible light and infrared light are output from one opening of the device.
[0004]
[Patent Document 1]
JP-A-10-303463 (summary, FIG. 1)
[0005]
[Problems to be solved by the invention]
However, in the above conventional example, the emitted light of the visible light LED and the infrared LED is combined, so that there is a problem that the configuration is complicated. It is also desirable for the user to be able to visually recognize each reception area when a plurality of different signal lights are transmitted to different areas in a partially overlapping manner .
[0006]
Therefore, in view of the above problems, the present invention allows a user to visually recognize each reception area with a simple configuration when transmitting a plurality of different signal lights to different areas in a partially overlapping manner. and to provide a can Ru the visible light receiver and a visible light communication device.
[0008]
[Means for Solving the Problems]
According to the present invention, the visible multiple visible light respectively in and different colors at different wavelengths of the plurality of signal intensity modulation to, and optical signals such that a portion of the receiving area is superimposed is transmitted, In the superimposition portion, a color different from the color of each visible light before being superimposed is visually recognizable, and a visible light receiving device that receives the optical signal,
When the visible light receiving device is arranged in at least two or more overlapping portions of visible light in the reception area, the visible light receiving device receives two or more superimposed visible lights at a ratio proportional to the reception intensity of each visible light. There is provided a visible light receiving device provided with visible light receiving means for demodulating the mixed modulated signal based on the intensity of the mixed modulated signal .
[0009]
Further, according to the present invention, an optical signal is transmitted such that each of a plurality of signals has a wavelength that is different from each other and a plurality of different colors of visible light is intensity- modulated and can be visually observed, and a part of the reception area is superimposed. In the superimposed portion, a plurality of visible light transmitting means that enables visually recognizing a color different from the color of each visible light before being superimposed,
In at least two superimposed portions of the visible light in the receiving area, based on said intensity of the superimposed two or more receiving the visible light, the modulated signal mixed at a ratio proportional to the reception intensity of each of the visible light Visible light receiving means for demodulating the mixed modulation signal;
A visible light communication device is provided.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a visible light communication device according to the present invention, FIG. 2 is an explanatory diagram showing a reception area of the visible light communication device of FIG. 1, and FIG. 3 is a diagram of the visible light communication device of FIG. It is a block diagram which shows a system configuration.
[0011]
FIG. 1 shows a karaoke apparatus as an example, and the R, G, and B visible light transmitters 1R, 1G, and 1B of the three primary colors are installed on the ceiling of the stage so as to project on the stage. The projected shapes of the visible light transmitters 1R, 1G, and 1B are shapes for explaining color reproduction by the additive color method as shown in FIG. 2, for example, and are configured to partially overlap. On the stage, receiving cards 2a and 2b for receiving the transmitted light of the visible light transmitting units 1R, 1G and 1B are placed so as to be arbitrarily movable, and headphones 3a and 3b are connected to the receiving cards 2a and 2b, respectively. The Note that it is more convenient for the user if the receiving cards 2a and 2b are integrated with a microphone (not shown).
[0012]
From the visible light transmitters 1R, 1G, and 1B, for example, as shown in FIG. 2, optical signals obtained by modulating the R, G, and B visible lights with the audio signals of the piano, vocal, and guitar channels are transmitted. The Therefore, in the R-only area projected on the stage, only the optical signal obtained by modulating the R visible light with the piano audio signal is received. In the G-only area, the G visible light is received with the vocal audio signal. Only the modulated optical signal is received, and in the B-only area, only the optical signal obtained by modulating the visible light of B with the audio signal of the guitar is received.
[0013]
Further, in the Y (yellow) area where R and G are superimposed, a vocal with a piano is received, and in the C (cyan) area where G and B are superimposed, a vocal with a guitar is received, and B and R are superimposed. In the M (magenta) area, a piano / guitar ensemble (karaoke) is received. For this reason, in the Y, M, and C reception areas, two channels are received. In the W (white) area where all of R, G, and B are superimposed, all three channels, that is, vocals with piano / guitar are received.
[0014]
Next, the system configuration of the karaoke apparatus will be described with reference to FIG. First, on the transmission side shown in FIG. 3A, each of the R, G, and B visible light transmitters 1R, 1G, and 1B includes a plurality of red LEDs so that a sufficiently large area can be projected on the stage. It consists of a red LED array 10R, a green LED array 10G, and a blue LED array 10B in which green LEDs and blue LEDs are arranged. A power source is commonly supplied from the universal power supply 11 to the red LED array 10R, the green LED array 10G, and the blue LED array 10B. Have been supplied. Also, each of the audio signals of the above three channels is AM-modulated by the AM modulators 12R, 12G, and 12B, and the common local oscillation frequency signal from the local oscillator (local oscillator) 13 is modulated. The red LED array 10R, the green LED array 10G, and the blue LED array 10B are supplied.
[0015]
Therefore, the red LED array 10R, the green LED array 10G, and the blue LED array 10B transmit optical signals whose intensity is modulated by the audio signals of the three channels. For this reason, in the Y, M, C, and W areas where the colors are superimposed on the stage, the signals are received at a level that is proportional to the R, G, and B received intensities.
[0016]
In the receiving card 2 shown in FIG. 3B, the optical signal is received by the PD 21 and mixed by the O / E converter (O / E) 22 at a ratio proportional to the R, G, B optical reception intensity. Received as a modulated signal. Since each of the mixed AM modulated signals is a signal modulated by a common local oscillator at the time of modulation, a synchronization relationship is ensured and mixed. Therefore, the mixed AM modulation signal is then converted into an audio signal by the AM demodulator 23. The converted audio signal is mixed at a ratio proportional to the intensity of each AM modulation signal. Next, the mixed audio signal is amplified by a headphone (AMP) amplifier 24 and applied to the headphones 3.
[0017]
In the above embodiment, an audio signal is used as a signal form to be transmitted by visible light, and a karaoke apparatus is taken as an example of a system configuration. However, the present invention is not limited to an audio signal and a karaoke apparatus, and content data, etc. Since it can be applied to all signal forms, it can also be applied to, for example, game machines and PC-to-PC communications.
[0018]
【The invention's effect】
According to the present invention described above, since the to transmit visibly modulates and different colors of visible light at each at different wavelengths of the plurality of signals, some of a plurality of different signal lights When transmitting to separate areas in an overlapping manner, each reception area can be visually recognized by the user with a simple configuration.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment of a visible light communication apparatus according to the present invention.
FIG. 2 is an explanatory diagram showing a reception area of the visible light communication device of FIG. 1;
3 is a block diagram illustrating a system configuration of the visible light communication apparatus in FIG. 1;
[Explanation of symbols]
1R, 1G, 1B Visible light transmitter 2a, 2b Reception card 3a, 3b Headphone 10R Red LED array 10G Green LED array 10B Blue LED array 11 Universal power supply 12R, 12G, 12B AM modulator 13 Local oscillator (local oscillator)
21 PD
22 O / E converter (O / E)
23 AM demodulator 24 Headphone (AMP) amplifier

Claims (3)

Optical signals are transmitted so that each of a plurality of signals has a different wavelength and a plurality of different colors of visible light can be viewed by intensity modulation, and a part of the reception area is superimposed. Is a visible light receiving device that receives the optical signal in a manner in which a color different from the color of each visible light before being received can be visually recognized,
When the visible light receiving device is arranged in at least two or more overlapping portions of visible light in the reception area, the visible light receiving device receives two or more superimposed visible lights at a ratio proportional to the reception intensity of each visible light. A visible light receiving device comprising visible light receiving means for demodulating the mixed modulated signal based on the intensity of the mixed modulated signal . Each of the plurality of signals transmits an optical signal so that a plurality of visible lights having different wavelengths and different colors are intensity- modulated to be visible, and a part of the reception area is superimposed. A plurality of visible light transmitting means for visually recognizing a color different from the color of each visible light before
In at least two superimposed portions of the visible light in the receiving area, based on said intensity of the superimposed two or more receiving the visible light, the modulated signal mixed at a ratio proportional to the reception intensity of each of the visible light Visible light receiving means for demodulating the mixed modulation signal;
Visible light communication device provided. The visible light transmitting means includes
A local oscillator that oscillates at a predetermined local oscillation frequency;
A plurality of modulation means for intensity- modulating a plurality of oscillation signals of a common local oscillation frequency respectively supplied from the local oscillator, with each channel of a plurality of channels of audio signals;
Visible light emitting means for converting each signal intensity- modulated by each of the plurality of modulating means into visible light having a different wavelength and transmitting the visible light so that a part of two or more receiving areas overlap each other. And
The visible light receiving means includes
Photoelectric conversion means for receiving and photoelectrically converting two or more superimposed visible lights when positioned in the overlapping portion of each visible light in the reception area;
It demodulates the signal obtained is converted by the photoelectric conversion means, based-out sound intensity of the superimposed two or more modulated signals each channel are mixed at a ratio proportional to the reception intensity of the visible light The visible light communication apparatus according to claim 2, further comprising means for reproducing a voice signal.

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