An apparatus and method for generating a mode-scrambled optical signal. A
laser beam source directs an optical signal into a free end of a first
segment of multimode fiber comprising a graded-index (GI) fiber core at an
offset from the centerline of the core, generating an offset-launch
condition. The first segment of multimode fiber is operatively coupled
into a second segment of multimode fiber comprising a step-index (SI)
fiber core. As the offset-launched optical signal passes through the first
and second segments of multimode fiber, the optical signal is converted
into a mode-scrambled optical signal having a substantially-filled
numerical aperture.
