The present invention provides an apparatus comprising a passive optical
transmission fiber. The passive optical transmission fiber comprises a
passive glass fiber core, a glass optical inner cladding surrounding the
core and a glass optical outer cladding surrounding the inner cladding.
The inner cladding has a lower index of refraction than the passive glass
fiber core and the outer cladding has a lower index of refraction than
the inner cladding. The passive optical transmission fiber also comprises
a second optical segment coupled to the optical fiber. The second optical
segment is configured to dissipate light in the inner cladding.