POF - Plastic Optical Fiber (also Polymer Optical Fiber): An optical fiber made from a polymer or plastic.
Plastic light guides have a surprisingly long history. Soon after its invention in 1928, the transparent plastic polymethyl methacrylate (PMMA) began replacing quartz in a variety of applications, including bent rods used as dental illuminators. Early developers of fiber-optics tested transparent plastics as well as glass in the 1950s, and plastic was used as a cladding on some of the first clad optical fibers.
For many applications, plastic had important advantages over glass. Plastic is lightweight, inexpensive, and flexible rather than brittle. Thin sheets of clear plastic, like thin sheets of window glass, seem quite transparent. But reducing the attenuation of plastic proved far more difficult than improving the clarity of glass, and plastic was left in the dust when the first low-loss silica fibers were demonstrated in 1970s.
Developers of plastic fibers turned to other light-guiding applications where fiber loss was less important than in telecommunications. By the early 1970s, bundles of plastic fibers were being used in decorative lamps, with the fiber ends splayed out to sparkle with light at their ends. Fiber-optic pioneer Will Hicks strung plastic fibers through a plastic Christmas tree, which he hoped to sell for holiday decoration until it failed an impromptu fire test at a New York trade show. Despite such reverses, plastic fiber-optic decorations live on.
POF communications also survives in short-distance applications where the low cost and ease of termination of plastic fibers offsets their high attenuation. One example is the Media Oriented System Transport (MOST) network for automobiles, which red LED transmitters to transmit signals through up to 10 meters of POF linking electronic systems in cars. Auto mechanics don't need an expensive fusion splicer to connect the large-core step-index fibers. Japanese researchers have developed graded-index POFs with bandwidths high enough to transmit 4.4 gigahertz up to 50 m at 670 to 680 nm, which developers hope could lead to applications in home networking.
Plastic optical fiber does have plenty of competition for the acronym POF, including polymer optical fiber and another optical term, "plane of focus." Acronymfinder.com lists 34 possible definitions ranging from the journal Physics of Fluids and the Pakistan Ordnance Factory to the dating site "Plenty of Fish" and "pontificating old fart". But plastic fiber fans can take heart -- the site ranks Plastic Optical Fiber ranks as the most-used definition of POF.
Modern decorative fiber-optic lamp, courtesy of Keck Observatory.