Abstract
We have conducted a feasibility study of a parallel moduling scheme based on a collimating guide using planar microlenses. This optical subsystem consists of a stacked planar optical circuit and a micro-optical bench (MOB) for alignment. We measured the coupling loss of microlens collimation and determined that single-mode fiber-to-fiber coupling of approximately 2 dB is possible. We also investigated the optical crosstalk of the collimating optical system using planar microlenses (PMLs), and the crosstalk of less than -70 dB was achieved. As an initial subsystem experiment using vertical cavity surface emitting lasers (VCSELs), we fabricated a VCSEL array (λ=850 nm, Ith=1.8 mA at room temperature, CW) and bonded it on a Si MOB.