PURPOSE: To obtain a small-sized optical multiplexer and demultiplexer by dividing one 1/2-pitch rod lens into four parts for the demultiplexing to four different wavelengths.
CONSTITUTION: The 1/2-pitch rod lens is divided into four parts 6aW6d axially and at right angles to the axis. Light with wavelength λ1 of light beams with wavelengths λ1Wλ4 from an input fiber 1 passes through a filter 3a and is reflected by a filter 3b, so the light is focused on an end surface of an output fiber 2a and outputted. The light beams of λ2 and λ3 are reflected by and transmitted through filters 3a and 3b similarly, and they are focused at end surface positions of fibers 2b and 2c and outputted. Consequently, demultiplexing into three waves is carried out.
IMOTO KATSUYUKI
SASAKI SHINYA
