Wavelength selective switching element

Abstract

The invention relates to a device and a method for switching optical wavelength channels. Said optical wavelength channels are introduced into at least one access waveguide provided on a first side of a first multi-mode waveguide (,). Subsequently, the wavelength channels are transmitted through said multi-mode waveguide (,) and projected on at least two connection waveguides provided on the opposite side. Subsequently, the optical wavelength channels are transmitted through the connection waveguides. For each wavelength selective cross-connection structure (,) the phase is changed for a reflecting wavelength of two phase control elements (C,, C,, D,, D,, E,, E,, F,, F,) arranged in a first and a second connection waveguide on a first side of said wavelength selective cross-connection structure (,), simultaneously as at a second side of said wavelength selective cross-connection structure (,) said reflecting wavelength phase remains relatively unchanged. For each wavelength selective cross-connection structure (,) the phase is changed for transmitting wavelengths once in a first and a second direction per wavelength selective cross-connection structure (,). The phase difference between the optical signal in each access waveguide provided on the first side of the second multi-mode waveguide (,) determines where the optical signal is focused on the opposite side.