Significantly robust data transmission by ballpoint-pen interconnect for graded-index plastic optical fiber

We have developed a novel optical interconnect for graded-index plastic optical fibers based on the use of ballpoint-pen connectors, where ball lenses are precisely mounted on fiber end faces by a simple and low-cost ballpoint-pen production technology. This report demonstrates that the ballpoint-pen interconnect allows us for significantly robust data transmission with sufficient misalignment tolerance and mating durability for consumer applications, where very short optical fibers are frequently connected and disconnected to the consumer electronics in a manner similar to metal cables. In the ballpoint-pen interconnect, power penalties are barely affected even by misalignments with a lateral offset of 50 μm or a connector separation of 1.0 mm, allowing for optical fiber connections without the requirements of precise alignment or high manufacturing accuracy. Moreover, it is suggested that modal noises due to dusts and scratches on fiber end-faces are generated for conventional butt-coupling based on physical contact in applications that require frequent connection and disconnection of optical fibers. This modal noise generation can be prevented using nonphysical contacts with the ballpoint-pen connectors. We achieve high-speed data transmission that is barely influenced by 2500 mating cycles. These results suggest that the ballpoint-pen interconnect allows us for consumer-friendly optical fiber connections without the requirement of any cleanings in a manner similar to electrical interconnect.