Ultrabroadband monolithically-fused 1/spl times/4 fiber-optic couplers

Summary form only given. Wavelength-division multiplexing (WDM) fiber-optic networks, including 1.3 and 1.55 /spl mu/m operations, demand 1/spl times/N couplers of low cost, small size and low excess loss for various system applications. A new monolithical fabrication method has been developed to efficiently produce broadband 1/spl times/N couplers, including 1/spl times/4 and 1/spl times/8 devices. The new 1/spl times/4 monolithically fused coupler consists of five identical fibers colinearly arranged in a plane.