PURPOSE: To carry out the two-way optical communication via the optical energy and with the base band analog transmission system of more than S/N 30dB by using the nonreflective 3dB branch/couple device, the nonreflective light source and the nonreflective light receiver each connected each other via the nonreflective connector.
CONSTITUTION: In nonreflective 3dB branch/couple device 7, part of the two pieces of the fiber is made flat each with part of the core exposed, four fiber terminals are formed through the coupling at the flattened area, and a slope featuring an angle larger than the threshold angle of the fiber is secured at the end face of each fiber terminal. Nonreflective light source 8 is connected to device 7 with the slanted luminous surface corresponding to the end face slope of fiber terminal 11 of device 7; nonreflective receiver 9 is connected with the tilted receiver surface according to the end face slope of fiber terminal 14 of device 7; and nonreflective connector 10 is connected with the tilted connection surfaces of other fiber terminal according to the end face slope of fiber terminal 15 of device 7 respectively. Thus, the two-way optical communication is ensured via the optical energy and with the base band analog transmission system of more than S/N 30dB.
SERIZAWA AKIYUKI
TANAKA TSUTOMU
TSUJIMOTO YOSHINOBU
