Misalignment-insensitive SNR with ballpoint-pen interconnect of GI POF

It is demonstrated that ballpoint-pen interconnect of graded-index plastic optical fibers (GI POFs) can allow for higher SNR for fiber-axis misalignment which cannot be tolerated for conventional butt-coupling of glass multimode fiber (MMF). In an MMF link with a vertical surface emitting laser, we evaluated coupling loss and relative intensity noise for ball-lens-coupled GI POFs which was developed with ballpoint-pen technology. The results show that the ball-lens coupling can significantly reduce coupling loss and transmission noise induced by fiber misalignment through expansion and collimation of output beam with ball lens. These properties of the ballpoint-pen interconnect can reduce required lanes using multilevel modulation scheme without additional noise-suppression components, paving the way for thinner 4K/8K interfaces for consumer applications.