| 摘要 |
PURPOSE:To execute an operation by using only one piece each of photoelectric converting element and optical fiber irrespective of the number of bits of a digital signal which is obtained in the end, by providing an optical branching means, an optical modulating element, and a P/S converting means, an optical modulating element, and a P/S converting means on a substrate. CONSTITUTION:Y-shaped optical waveguides 25-27, Mach-Zehnder type optical waveguides 21-24 being light intensity modulating elements, optical waveguides 41, 41a-44 and 44a for executing an optical parallel/serial (P/S) modulation, and Y-shaped optical waveguides 45-47 for condensing the light which has been brought to the P/S conversion are formed on a substrate 10 of a waveguide type optical A/D converting part. Light from a semiconductor laser 14 is made to multiplex equally to four lights by the Y-shaped optical waveguides 25-27, modulated by the Mach-Zehnder type optical waveguides 21-24, and thereafter, brought to the P/S conversion by the optical waveguides 41, 41a-44 and 44a, condensed by the Y-shaped type optical waveguides 45-47, and led into an optical fiber 16. |
