Conclusions about Plastic Optical Fiber technology

Plastic Optical Fiber technology has many advantages for the reduction of electromagnetic radiation generated by computer networks, but the technology hasn't been designed for this purpose exactly. As for many other products and systems, we have to use it in a certain way, selecting only some parts, in order to have some real benefits for what concern electromagnetic radiation removal. The Plastic Optical Fiber cable is the only part that is totally free of EM fields or radiation. All the electronic devices needed to use the POF cable emit more or less EMR. They could have been designed to minimize these emissions but they haven't, or the results are not good enough. By the way, we know that making electronic circuits that don't have any electromagnetic emissions is very difficult, almost impossible. Anyway, these systems work well as wired communication systems, so we have to find what we can get from this technology for the aim of having no electromagnetic radiation in the workplace.

Currently there are three types of devices that can connect a generic computer to a POF cable:

  1. a) the external POF media converter with RJ45 interface
  2. b) the external POF media converter with USB interface
  3. c) the internal POF LAN card for computers with PCI extension slots

Of these three the only device with acceptably low electromagnetic footprint is the internal POF LAN card, also called PCI POF NIC (Network Interface Card).

Both the external POF media converters have a lot of electromagnetic emissions coming from the circuit board, which is not shielded since it is just inside a plastic enclosure, and from the cables, either Cat5 or USB, and, for the RJ45 one, also from the external power adapter and its wire. The cables of the external media converter are difficult to control, as any other cable attached to a computer. They can easily pass EM noise to the cables of the computer peripherals like monitor, mouse, keyboard, microphone, headphones and speakers. Even if the POF converter cable is very short there is always the converter circuit board that emits a lot.

As usual these problems are simply ignored by the big industries and by the regulatory institutions, who just check that the devices do not cause interference to other similar devices up to a certain distance.

These devices may have passed all the EMC ( Electromagnetic Compatibility ) tests but they are not safe for what concerns human health. People who works many hours every day with computers cannot be subject to the electromagnetic radiation that spills out of these little devices. One thing is checking that the device doesn't harm people during a few minutes of exposure, another thing is to be sure that the device is safe even for people who are exposed to it continuously for hours and hours every day.

The conclusion is that Plastic Optical Fiber links are useful for having a very low EMR computer workplace but only if the computer is provided with a POF LAN card that is enclosed in the computer case.

For the other parts of the LAN we can use external POF media converters because the devices are supposed to be in a separate room, far from desks and workstations, and if for some reasons the devices have to be near a workstation then we can, and we need to, enclose them inside a suitable shielding.

Acknowledgements

We would like to thank again the companies that have provided us with free samples of POF electronic devices and cables.

The Homefibre company from Austria has provided us with a DIY kit for POF networks consisting in: two external POF media converters with RJ45 interface and their power adapters, two already made short Cat5 patches, 30 m of POF cable of the 2 x 2.2 mm type, and a special cutter. Homefibre not only distributes these products to European customers but also does research and development of new ways to install POF networks in homes. They propose POF sockets that can be installed into walls to have easy access to a POF based home network.

The MG-Future company from Germany provided us with an external POF media converter with USB interface. This company distributes fiber optic products and also Plastic Optical Fiber products mainly to industry and telecommunication companies.

For the POF PCI network card we didn't receive any free sample so we had to purchase the cards from a reseller in Europe. It seems that the PCI POF cards are currently manufactured by one company only, which is FiberRoad, from Hong Kong.

We have seen a few other manufacturers or large distributors of POF related components. People from USA or Australia should turn to distributors in their country for obvious reasons of shipping costs and customs duties.

Related projects

Our next project about Plastic Optical Fiber is an assembly of an ADSL modem router with 4 RJ45 ports and as many POF media converters, with internal power supply, AC filter, ADSL splitter filter, all enclosed in a good shielding box to protect us from the EM radiation that comes from the ADSL modem and wires. We call this an ADSL POF box . The first prototype has been built and used successfully and now we are building a second prototype. If you are interested in this project contact us .

Related pages

Plastic Optical Fiber overview
Distributors of Plastic Optical Fiber products
Plastic Optical Fiber page list