Higher quality video formats such as 4K/8K have emerged. Since these video formats require high speed communication which cannot be done with commercial copper cables to transmit uncompressed live video without latency, optical communication has been expected as an ideal solution. However, conventional silica optical fibers are not suitable to be handled by consumers for such high-speed short-reach applications, because of their fragileness and difficulties in precision connections at low cost. We propose a novel optical interconnect using a graded-index plastic optical fiber (GI POF) with each end having a glass spherical collimator lens uniquely fabricated by low-cost ballpoint pen technologies. As one of promising applications of the interconnect, improved 8K endoscope camera and its CCU (Camera Control Unit) will be discussed for medical use. At an operation room in a hospital, surgeons need to handle the camera. Video cables are inserted, bended, removed, and exchanged frequently during the operation. Silica optical fibers are not flexible for such frequent handling application. To overcome the problems, optical modules, optoelectronic composite cables using GI POF, and the ballpoint-pen interconnect were developed. Using the system, 8K video from the endoscope camera was successfully transmitted at our verification experiments.