Photosensitivity in optical fiber waveguides: from discovery to commercialization

The photosensitivity of germanium-doped-core optical fibers was discovered more than twenty years ago. The discovery provided a means for photoimprinting gratings in the core of optical fibers, and eventually photosensitivity became an important technology for fiber-optic communications. The paper recounts briefly the story of the photosensitivity of optical fiber waveguides and the significant developments that occurred on the journey from its discovery to its commercialization as is often the case with many inventions, the discovery was serendipitous. Furthermore, several technical and nontechnical developments were necessary before the discovery could be exploited commercially. In the case of photosensitivity, the time span from discovery to commercialization was relatively long-about 15 years.