The fibers which relax the spectral requirements for optical sources and allow flexible wavelength division multiplying are known as __________

Optoelectronics and Optical Communication 

The fibers which relax the spectral requirements for optical sources and allow flexible wavelength division multiplying are known as __________

a) Dispersion-flattened single mode fiber 
b) Dispersion-enhanced single mode fiber 
c) Dispersion-compressed single mode fiber 
d) Dispersion-standardized single mode fiber

Answer : - Dispersion-flattened single mode fiber

The dispersion-flattened single mode fibers (DFFS) are obtained by fabricating multilayer index profiles with increased waveguide dispersion. This is tailored to provide overall dispersion say 2psnm -1 km -1 over the wavelength range 1.3 to 1.6μm.