Patent ID: 6501877
Filing Date: 2002-12-31
Classification: G02B,H04J,H04Q

Abstract:
A wavelength router for receiving light having a first number, N, of spectral bands at an input port and directing subsets of the N spectral bands to respective ones of a second number, M, of output ports, the wavelength router comprising:a first cylindrical lens for collimating light emanating from the input port in a first transverse dimension; a second cylindrical lens for collimating the light in a second transverse dimension that is orthogonal to the first transverse dimension; a transmissive dispersive element for dispersing the light in the first transverse dimension in a particular sense; a third cylindrical lens for focusing the light in the first transverse dimension; a plurality of N tiltable mirrors in the focal plane of said third cylindrical lens, each intercepting a respective spectral band and directing that spectral band back toward said third cylindrical lens; and a plurality of actuators, each coupled to a respective tiltable mirror to effect selective tilting of the light path of the respective spectral band; wherein each spectral band is collimated in the first transverse dimension by said third cylindrical lens, dispersed in the first transverse dimension by said dispersive element in a sense opposite the particular sense, focused in the second transverse dimension by said second cylindrical lens and focused in the first transverse dimension by said first cylindrical lens, whereupon each spectral band is brought to a focus in both the first and second transverse dimensions at a respective position determined by the respective tiltable mirror.