OPTICAL FIBER TRANSMISSION DEVICE

摘要

PURPOSE:To transmit an analog signal with high quality and broad band at a long distance by a method wherein the outgoing beams from a laser diode are made parallel beams by means of a lens further selectively reflected by an optical element to feed them back to the laser diode making use of a single mode optical fiber arranged diagonally to an fiber optical axis. CONSTITUTION:The outgoing beams from one end of LD1 is made parallel by means of a collimating lens 2 while the beams only selected by an optical element 3 selectingly reflecting the outgoing beams from LD with specified wave length which is repeatedly reflected by LD1 to be optically fed back. On the other hand, the outgoing beams from the other end of LD1 are led by a fiber 4 which is a short fiber to take the outgoing beams from LD therein transmitting them to a fiber for transmission 5. These reflecting beams may be emitted out of the fiber without being transmitted in reverse direction by means of arranging fiber ends 101, 102 and 103 diagonally to the fiber optical axis.