back to article Japanese boffins say they've created plastic optical fibres to reach places that might break glass

Boffins at Japan's Keio University reckon they've built viable optical fibers from plastics. Optical fibers are most often made of glass and are, as attested by the awesome data-schlepping capacity of undersea cables, freaking amazing. But while boffins have made optical fibers very resilient, they've not been able to address …

  1. IGotOut Silver badge


    Other than jumping on the "Connected Car" bandwagon that only Car manufacturers and governments seem to want, why on earth do you need fibre optics in a car?

    We've gotten pretty good at car electrics these days.

    1. John Sager

      Re: Why?

      I'm pretty sure the Saab 9-3 I used to have had optical fibres to the light cluster controllers at the back. One obvious solution is to have the 12V bussed around to local controllers for whatever and have optical fibres for the CAN bus to control everything. That makes the wiring loom much simpler as variants for different markets and models are a local controller change or even just a different software build.

      1. Def Silver badge

        Re: Why?

        Having been a fan of Project Binky for some years now I was amazed at how chaotic the wiring loom could get in a small car.

        1. bazza Silver badge

          Re: Why?

          And Binky counts as a somewhat minimal electrical installation in a car these days.

    2. Chris G Silver badge

      Re: Why?

      Also, using more plastic in an application such as vehicles that are relatively shortlived is another addition to the list of difficult or impossible to recycle materials that end up in the environment.

      The amount of non renewable materials and unnecessary electronics that goes into vehicles now is absurd.

      1. W.S.Gosset Silver badge

        Re: Why?

        Wait till they all go electric! Mmmm... batteries...

    3. Anonymous Coward
      Anonymous Coward

      Re: Why?

      POF is a big weight-saver compared to copper wire harnesses.

    4. Anonymous Coward
      Anonymous Coward

      Re: Why?

      In case of EMP.

      1. Anonymous Coward
        Anonymous Coward

        Re: Why?

        Not as daft as it sounds. Car engines themselves are a constant source of EMPs. All the electronics in a car need suppression and shielding all over the place. Replacing the signal wiring that acts as an antenna picking all this up with a fibre would help.

        However I do wonder how car light bulbs and windows work if glass can't be used in cars.

        1. Charles 9 Silver badge

          Re: Why?

          Light bulbs and car windows are both hardened to be shatter-resistant (typically, side window glass is tempered while windshield glass is laminated). IINM, shatter-resistance doesn't work well with glass fibers, so using optical plastics for a car's internal data bus sounds like a plausible idea.

          Also mentioned, using these in a modestly-sized data center also sounds nice. Could reduce costs, increase layout options, or both.

    5. elsergiovolador Silver badge

      Re: Why?

      why on earth do you need fibre optics in a car

      If it's a special fibre optic, that you can buy once in a full moon or it is serialised so it will only work with your car, then it means billions of potential profit for "authorised repair shops". If a mice take a bite of that fragile fibre, there goes your month's salary.

      1. Andy The Hat Silver badge

        Re: Why?

        Tut Tut Sir. When you hit the post you appear to have slightly scratched the fibre surface and it's producing reflections so the signal is being attenuated and the auto-gear knob warmer is set to maximum when a high bmi passenger sweats near the demist sensor for the heated rear screen. That'll be a complete rip out and fibre refit at £2000 please ...

        1. Anonymous Coward

          Re: Why?

          You obviously have never experienced this IRL. You couldn't sniff a replacement for that cost.

          My old (few mod cons) VW GTI was totaled by the insurance company after rodents chewed through the wiring harness. The cost to install a new copper harness was $10000 (about £7500) and it was cheaper for the insurance company to buy the car.

    6. SkippyBing

      Re: Why?

      I had an '07 plate BMW 3 series and that had a fibre optic loop connecting the elements of the entertainment system together. I'm not really sure what advantage that gave apart from making it not worth the hassle of fitting an after market system so the three previous owners hadn't ruined things with a ridiculous head unit.

    7. bombastic bob Silver badge

      Re: Why?

      as long as you have power available on copper, you can send data by fiber and it will most likely be a MUCH smaller cable, and apparently more resilient to age and even bending and vibration [using polymer], and the one thing that makes the most sense in a vehicle: LIGHTER WEIGHT (and probably lower cost).

      And copper can be expensive. So if fiber is cheaper, between the window and lock controls and the car computer [for example], with a bendy cable going into the doors from the car's frame, you need to be able to handle repeated bending, vibration, moisture, heat, cold, and other things that make wires go bad. And, probably , GLASS fiber optics. But maybe not polymer.

      And again, copper is expensive. And relatively heavy. So yeah.

  2. Schultz

    "Critically, the materials are said to have less requirement for forward error correction"

    I must be missing something here:

    (1) The material surely doesn't need forward error correction, but the data transmission might become more reliable with FEC.

    (2) The degradation of information as it is transmitted through a cable (fiber) is distance dependent: Errors accumulate as the path gets longer. Clearly the plastic fibers are meant for short distances, because the optical quality of plastics is usually inferior to that of high quality glass. So I would expect that for a comparable fiber lengths, the polymer fiber would accumulate more errors. Maybe they compared a meter-long polymer fiber to a km-long glass fiber? Or maybe something got lost in translation.

    1. Paul Kinsler

      Re: "Critically, the materials are said to have less requirement for forward error correction"

      I'm not sure how it would affect error correction in this case, but perhaps the types of errors are different; e.g. due to the different propagation or scattering properties in the different types of fibre. All errors are not necessarily the same.

      1. Spoobistle

        Re: "Critically, the materials are said to have less requirement for forward error correction"

        My rather non-technical understanding about transmission down fibres (and I think this applies to copper as well as optics) is that there are two distance related problems: (i) you lose intensity of the signal so eventually you can't pick it out of the noise; (ii) the signals "smear out" so that a set of nice rectangular pulses going in turns into rolling humps at the other end. These are related to absorption loss and dispersion respectively. My guess is that the Japanese have come up with a plastic fibre that's ok for one of these but not so good for the other, hence the short distance limitation. (It might well say which in the Keio U. announcement but I can't read Japanese!)

        1. Yet Another Anonymous coward Silver badge

          Re: "Critically, the materials are said to have less requirement for forward error correction"

          Which makes sense. If I'm running 1m long patch cables or wiring a machine why do I need to use the same ultra-fragile low-loss material you need for 5000km undersea links

  3. David Pearce


    I hope that this polymer does not go brittle after 5 years of temperature cycling. Modern cars are potentially very short lived.

    1. elsergiovolador Silver badge

      Re: Lifetime

      Probably the whole point - once the lease ends, you won't be tempted to buy the car and you will get a lease on a new one.

    2. Andy The Hat Silver badge

      Re: Lifetime

      It will be in a duct with a simple plug-in termination at each end so it can be blow/sucked through and replaced easily and quickly for a few quid.

      Do I see a cloud with a cuckoo preening before me ...?

      1. Anonymous Coward
        Anonymous Coward

        Re: Lifetime

        Riiiiight. Like the key-fobs still using 1990's radio technology are now only $3 a pop to replace...

        No, it's got "optical fiber" in the name, so it's mystical and magical to the wrench monkeys, and hence will cost a least 10 times what the same spec cable would cost from CDW or FONetworks.

  4. Kevin McMurtrie Silver badge

    Good for patch cables

    This would make for good patch cables, assuming fiber jacks ever become cheap enough to go mainstream.

    Another would be scientific instruments needing extreme noise or voltage isolation.

    I'm not so sure about automobile use. As others have said, the only advantage is reducing the need for EMP-safe signaling. That's not a big deal because every device still needs giant inductor-diode-resistor-capacitor power filters.

  5. jon90909

    But how cheap will it REALLY be?

    I would hope for cheap and easy termination in the field, even for the relatively untrained individual. Beyond that, if they could just stretch the tech to a few hundred meters, could this make cheap installs for FTTH a reality?

    1. Jon 37

      Re: But how cheap will it REALLY be?

      FTTH install cost has almost nothing to do with the cost of the fiber. The cost is in digging and installing the duct, and putting the fiber into it.

    2. Roland6 Silver badge

      Re: But how cheap will it REALLY be?

      Well the evidence from the 1980's when plastic fibre made its debut is that it is as good as glass over short distances, such as those found in the telco local loop and internal to office buildings. This combined with its easy to terminate properties (simply cut with a sharp knife) would seem to make it preferrable to glass. However, for some reason it hasn't taken off.

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