The Light Transmission Nature of Glass
Transmission down optical fibers is generally in the near infra-red band of frequencies. In this range of frequencies the optical fiber exhibits the lowest signal attenuation. Figure 4 illustrates typical attenuation characteristics of glass that is used in fiber optics. Note that this curve does vary to some degree depending on the type of glass used for manufacture and the type and degree of impurities infused into it.
Figure 4. Typical
Attenuation Responses for a Fiber