SYSTEMATIC DESIGN OF NOVEL WIDE-ANGLE LOW-LOSS SYMMETRICAL Y-JUNCTIONWAVE-GUIDES

To construct a low-loss and wide-branching-angle symmetric Y-junction waveguide, a novel structure is proposed, The structure consists of a pair of microprisms for precompensation and a microprism for phase-fro nt acceleration. The structure of the Y-junction and the associated re fractive indexes of microprisms are systematically derived, The simula ted results using the fast Fourier transformation beam propagation met hod (FFT-BPM) demonstrate the performances of the proposed structure, The normalized transmitted power is more than 95 % even though the bra nching angle is up to 20 degrees.