Hollow Optical Waveguide Coupler for Portable Access Card System Application

Abstract

A new application of an asymmetric hollow optical waveguide coupler is presented. The asymmetrically-design hollow waveguide coupler provides a unique series of output power which successively is used as an optical code in a portable access card system. The output power are arranged in a way that it will represent a unique optical code. The waveguide design combines two major structures which are asymmetric Y-junction splitter and linear taper. The use of a basic lx2 asymmetric waveguide coupler design together with a cascaded design technique allow more complex and higher level hollow waveguide coupler to be constructed. The code combination generated by the waveguide coupler theoretically provides the access card system with millions of possible code combination as the number of output ports increases. The code combination of the waveguide coupler is derived using combinatory number theory where the combination is dependable on the number of output ports.