Patent ID: 6571031
Filing Date: 2003-05-27
Classification: G02B,H04J

Abstract:
A device for demultiplexing a wavelength multiplexed optical signal comprising at least a first and a second optical wavelength channel centered around respective predetermined wavelengths (&lgr;1, &lgr;2), said device comprisingan MMI coupler, at least of the size 2Ã—2, for inputting the wavelength multiplexed optical signal at an input and for splitting the multiplexed signal into components and imaging these at several ports, Michelson waveguides for receiving and transporting the components imaged at the ports of the MMI coupler, reflecting means for reflecting the components received and transported in the Michelson waveguides back to the ports of the MMI coupler, wherein the MMI coupler is arranged for inputting the reflected components, the respective lengths of the Michelson waveguides are adapted so that said MMI coupler combines the components in such a manner that the first and the second optical wavelength channels are imaged substantially at different outputs of the MMI coupler, and the lengths Lk of the respective Michelson waveguides are adapted according to Lk=L0+(kw/2N) where L0 is a given arbitrarily chosen length, k is an index of the respective waveguide, N is the number of Michelson waveguides in the demultiplexer and w=&lgr;2/(&Dgr;&lgr;ng), in which expression &lgr; is the center wavelength of the incoming wavelength multiplexed optical signal, &Dgr;&lgr; is the wavelength distance between the first and the second optical wavelength channel and ng is the group refractive index of the Michelson waveguides.