Acrylic-based Y-branch plastic optical fiber attenuator

A low cost acrylic-based Y-branch plastic optical fiber (POF) attenuator has been developed. The device is based on a simple Y-branch structure and composed of three segments: an input POF waveguide, a middle variable hollow waveguide taper and output POF waveguides. Non-sequential ray tracing model has been performed on the device showing the device working as simple two-port attenuator. The device mold insert has been fabricated using a desktop engraver machine with a U-groove opening of 1 mm which allows 1 mm core size POF fibers to be slotted into the mold insert. The attenuation of the device can be adjusted by a simple waveguide taper spacing controlled by the spacing of the input POF fiber in the hollow region. The device has a channel uniformity of 0.3 dB, coupling ratio of 53:47 and excess loss of 3.7 dB. Device attenuation ranges from 6.9 dB to 9.4 dB has been obtained for a waveguide taper spacing of 0 to 6 mm.