| 摘要 |
PURPOSE:To transmit analog signals without being affected with the change in the attenuation of transmission lines, by using the modulation system changing the wavelength of transmitted light. CONSTITUTION:A transmitter 1 which is provided with a plurality light sources (LEDs or the like) 2a, 2b having different wavelengths lambda1, lambda2 and in which the ratio of output light of the light sources 2a, 2b depends on an electric signal Vi to be inputted, is provided. Further, the transmitter 1 takes the electric signal Vi as the input and outputs a light having a wavelength determined with the signal Vi. The output light is led to a receiver 5 through an optical fiber 3. The receiver 5 has photodiodes 4a, 4b having different spectral characteristics and outputs a voltage Vo or a current corresponding to an equivalent wavelength depending on the output ratio of the outputs of the light sources or the wavelength of the light of the transmitter 1. |
