A team of Japanese scientists working at Keio University have managed to develop a solution for “error-free” plastic (polymer) optical fibre cables, which can solve some of the cost, delay and heat generation problems that have tended to restrict their use. Data speeds of 53Gbps (Gigabits per second) were achieved.
Firstly, there’s nothing particularly new about creating fibre optic cables out of plastic, although glass (silica) fibre tends to do a better job. But the reason why you might want a plastic fibre is because such cables can be cheaper to manufacture, are easier to use (no special training require) and are more durable than glass, particularly with respect to bending and stretching.
As a result of all this you tend to find that plastic fibres, which can’t achieve the same sort of speeds as glass fibre, often end up being used for lower speed, short-distance style setups (e.g. they’re handy for use inside a home or office). Take note that “lower speed” is a relative term, since we’re still talking about multi-gigabit territory.
However, the researchers found they could improve polymer based optical fibre cables by “actively utilizing the mode coupling caused by light scattering in the cable“, which resulted in much faster and largely “error-free” data speeds (i.e. 53Gbps via the Four-level Pulse Amplitude Modulation [PAM4] method, which is said to be the “next-generation standard for data centre communication“).
The full press release for all this is written in Japanese and, sadly, online translators tend to struggle with scientific terminology, thus we’re hesitant to go into more depth for fear of reflecting mistakes from that translation. The key takeaway from all this is that faster fibre optic cables, based on plastic, now look much more plausible.
Statement from the Research Team (Translated)
“With the advent of the AI and IoT era, large-capacity and high-quality data communication is required for servers and computer devices, but it is becoming difficult to transmit data without error as the speed of signals increases. Many current communication systems use error correction functions such as FEC (Forward Error Correction) and waveform shaping circuits to correct erroneous data that occurs during transmission, but this signal processing consumes the communication system. Increasing power and communication delays have become a major problem.
The error-free POF developed [by this team] eliminates the need for error correction functions and waveform shaping circuits in the above communication systems, and can solve the problems of heat generation, delay, and cost of communication systems at once. This result not only saves power in data centers, but also paves the way for large-capacity real-time communication in automobiles, medical care, robotics, etc., and error-free POF will become a core technology in the next-generation information industry.”
As above, this remains an inherently short-range technology, which restricts its use to devices and environments (robots, homes, data centres etc.) where only shorter cables are required (often up to 100 metres). Further details of the results from this research will be announced at the International Conference on Plastic Optical Fibers (POF2021), which is due to be held in November 2021.
Brilliant! Toslink updated for its 40th
Hopefully this can drive even more innovation and maybe in the longer term some environmental benefits. Although one thing I couldn’t find was any reference to projected signal degradation over time vs glass fibres, in other words does the polymer itself degrade faster than glass? (I used Deepl for the translation which generally does a much better job than google)
A winner for the aviation and automotive industries ?
Firstly fibre is already as cheap as chips. Cheaper than copper, and terminating plastic is no easier. Second modern fibre is really rather robust, with bend radius of millimetres. Waste of time innovation IMHO.
This was meant for commercial uses, needless to say companies aren’t looking to compare prices with copper when buying fibre.
A glass vs plastic cost comparison is more suitable.