Image: Adam Singer / Flickr (source) (CC BY-ND 2.0)
Plastic Optical Fiber in the Automotive Industry
The Need for Speed
The complexity of electronic systems in vehicles has increased significantly in the past several decades, providing drivers with an Internet-enabled driving experience, in addition to comprehensive vehicle monitoring and safety systems. To achieve near real-time responsiveness, the backbone for these features must be both robust and support high-speed data rates.
Advantages of POF
POF is the medium of choice for automotive networks primarily due to its versatility. With age and temperature variation, its light attenuation per unit length remains relatively constant, resulting in maximum optical performance over a long service life. It can withstand tighter bending radii than glass optical fiber, which allows it to be bundled into copper wiring harnesses. POF also performs consistently well in all of the high-temperature environments of a car, such as the engine bay and roof, which can reach 125°C.
D2B and MOST Standards
POF has been used by automakers since the late 1990s, where it was first introduced by DailmerChrysler in the S-Class luxury car. This network made use of its own cable/connector system and the D2B protocol. Shortly thereafter, the MOST standard was introduced, which improved upon D2B, and has since been adopted by all major automakers worldwide.
The MOST standard and organization was founded by German automakers DaimlerChrysler, BMW, Volkswagen, Audi, and Porsche, but the list of automakers that incorporate it includes Toyota, Honda, Ford, Land Rover, Opel, Saab, Jaguar, Nissan, Renault, Volkswagen, Aston Martin, GM, Porsche, Volvo, and Fiat. These automakers have teamed up with manufacturers of infotainment and telemetry systems, such as Alpine, Philips, Infineon, Bosch, Sony, Molex, Agilent, Kenwood, SHARP, Nokia, Motorola, Pioneer, Delco, and Bose.
POF as a Sensor
The versatility and unique light propagation properties of POF also lend it to sensor applications, where the fiber itself can be used as a sensor. In cars, POF sensors are used to detect hood deformation that occurs in an accident and trigger airbag deployment.