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The thesis mainly discusses how to increase the optical
coupling efficiency between a laser array and a single-mode
fiber array, and to explore their packaging technology for
fiber communication. We fabricated a hemispherical microlens on
the fiber end to couple light from the laser. The coupling
efficiency was measured more than 40%. The lensed fiber was
made by first tapering a bare fiber through chemical etching,
and then by forming a microlens at the tapered end through
carbon dioxide laser heating. Such a fabrication process can
potentially allow mass production. In addition, we simulated
and measured the return loss of lensed fibers for different
radii. Typical values of return loss were measured of 14.4dB
for free end fiber. Fibers were precisely clamped between two
identical silicon V-groove to comprise an array before forming
microlens. The spacing of two adjacent fibers was of 250μm,
identical to that of two neighboring lasers. The silicon V-
groove was fabricated by KOH wet etching. A coupling efficiency
of 20% was achieved between a laser array and a fiber array. To
package a laser and a lensed fiber, we firstly fixed the fiber
in a copper-plating tube, and assembled the laser and the fiber
on the same substrate using solders of different melting
points. Due to the possible effects of shrinkage and
misalignment , a coupling efficiency of 20% was achieved. In
addition, we made some proto-type high-speed microwave driving
circuits for the laser.
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