It's not useful to transmit light through air; instead waveguides are used[0]. I don't know all the benefits, but I imagine trying to keep a path through space

It's not useful to transmit light through air; instead waveguides are used[0]. I don't know all the benefits, but I imagine trying to keep a path through space for light beams to travel is harder than using a waveguide. In that case, mirrors are useless. You can think of a waveguide as being a highly engineered mirror, really. However, the turning radius of a fiber-optic beam isn't great, and apparently this is an improvement on that. http://en.wikipedia.org/wiki/Waveguide#Optical_waveguides http://en.wikipedia.org/wiki/Waveguide#Optical_waveguides