| 摘要 |
PURPOSE:To simplify the constitution of the device by assigning a prescribed frequency to a level of transmitted data and using a prescribed frequency for a driving frequency of lighting fluorescent light in response to the level of the transmitted data to transmit the transmitted data in the form of light. CONSTITUTION:A data signal (a) transmitted from a transmission signal generator T is received by a modulator M, the signal is subjected to frequency keying (FSK) modulation to generate a fluorescent light driving signal (b). The driving signal (b) drives a fluorescent F, the light from the fluorescent light F is received by a receiver R to demodulate the transmission data. Prescribed frequencies f0, f1 are assigned in advance to a level (0 or 1) of the data transmitted to the modulator M and the fluorescent light F is driven in response to the frequency. Then the receiver R is constituted by a pin photodiode P, an amplifier A, a band pass filter FT and a waveform shaping circuit S to simplify the constitution of the entire data transmission system. |
