| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress reduction in S/N ratio of an optical signal transmission system by reducing noise resulting from a speckle pattern. <P>SOLUTION: An electric signal is converted to an optical signal by a laser diode LD 16. A high-birefringence waveguide 18 is connected just after the LD 16. The waveguide 18 is formed of a pigtail type high birefringence plastic optical fiber POF 20. The coherence of the optical signal is reduced by birefringence of the POF 20 to reduce speckle noise. In the inexpensive optical signal transmission system 10 including the LD16 and a multi-mode optical fiber 12, the speckle noise can be reduced to suppress the reduction in S/N ratio. <P>COPYRIGHT: (C)2010,JPO&INPIT |
