| 摘要 |
<P>PROBLEM TO BE SOLVED: To inexpensively constitute each optical transmitting/receiving device and to mitigate assembly precision concerning a single core two-way optical transmission system with asymmetrical transmission speed. <P>SOLUTION: The respective optical transmitting/receiving devices 10, 20 include light emitters 11, 21, light receivers 12, 22, beam splitters 13, 23, and lenses 14, 24, and are connected with a single core optical fiber cable 30. A light emitting diode is used for the light emitting element 21a of the light emitter 21 which generates transmission light for transmitting data at lower speed in the optical transmitting/receiving device 20. A photodiode with lower response speed is used for the light receiving element 12a of the light receiver 12 in the optical transmitting/receiving device 10 which receives the transmission light. The light emitting diode is more inexpensive compared with a laser diode to be operated at higher speed and the photodiode is inexpensive when the response speed is lower. When a light receiving signal is a narrow band, the light receiving element 12a with a large light receiving surface is adopted, so that precision concerning an attachment position is mitigated. <P>COPYRIGHT: (C)2007,JPO&INPIT |
