Biodegradable to nature… Optical fiber made of wood?

Finnish researchers have discovered a way to make functional fibers from wood. Fiber optic cables deserve to be called an unknown hero in the modern digital world. Unlike metal wires that carry electrical signals, these cables contain elongated threads made of glass or plastic that transmit light waves up to several kilometers and connect data centers to cities and even continents. The wavelength of light does not flow through electrons, but propagates through the optical fiber using a process called total reflection. Total reflection remains trapped inside while photons reflect off the inner wall of the transparent fiber and travel end to end.

Transmitting data with minimal error requires that these fibers are optically complete, and if made of wood, it appears to be the exact opposite. However, wood is not completely opaque, but depending on its thickness, moisture, and other additional substances, photons can pass through it.

The optical fiber cable developed by the research team at VTT Technology Research Center in Finland is made of wood cellulose, a structural material in which plants stand upright. In the manufacturing process, it is treated with a salt-based ionic solvent and then wrapped with an outer layer made of acetyl cellulose, which has a lower refractive index than the center. As a result, photons are reflected and caught inside, like fiber optic cables made of glass or plastic.

However, it will take a long time for this discovery to replace the traditional materials of fiber optic cables. Although its ability to transmit light wavelengths is lower than that of glass or plastic, it also shows unique properties useful for other uses as researchers improve performance. Since it is made of wood fibers, it can absorb water and affect its ability to transmit measurable light. For example, it could be used as a humidity sensor for structures made of wood and other materials that are not compatible with water. Since it is a material derived from nature, life may be a concern, but it is said that it can be used for a long time. Related information can be found here .