title: 3 x 3 single-mode star coupler made from 2 x 2 couplers.
abstract: An optical network made from two 3-dB and one 1.76-dB 2 x 2 single-mode couplers can perform as a 3 x 3 star coupler. One version is particularly suitable for polarization-preserving components and requires adjustment of the phase in one arm; it can also perform the three-point discrete Fourier transform by suitable adjustment of other phases. Experimental verification of the principle is presented.
authors.forename: M E
authors.initials: ME
authors.lastname: Marhic
authors.forename: Y L
authors.initials: YL
authors.lastname: Chang