An efficient tapered optical fiber bundle along with the method of manufacturing
is presented. The tapered fiber bundle is fully fused to an induced shape with
no interstitial space between fibers. To minimize fiber deformation and hence the
tapered bundle's loss, the individual fibers are minimally deformed by positioning
them in a fixture with predetermined geometry prior to fusion. The bundle could
be optionally reshaped after fusion. The tapered bundle could then be used in its
original form as a star coupler, or it could be cleaved and coupled to a multimode
fiber, a multi-clad fiber, a cladding-pumped fiber, or an optical system to form
an optical device. The resulting optical device has improved efficiency and lower
loss compared with prior art devices.