Patent ID: 6928207
Filing Date: 2005-08-09
Classification: G02B

Abstract:
1. An apparatus for selectively blocking WDM channels comprising: a light modulator comprising an array of pixels, each pixel selectively operable to direct light into a first mode and a second mode, the first mode directing the light to an output and the second mode directing the light away from the output, wherein the light modulator comprises a grating light valve type device, and wherein the first mode comprises a reflection mode and the second mode comprises a diffraction mode; a diffraction grating operable to receive the WDM channels from an input and to disperse the WDM channels into a range of angles; a transform lens coupled to the diffraction grating and operable to transform the range of angles of the WDM channels into a range of spatially distinct positions along the array of pixels without overlap of two of the WDM channels on an individual pixel such that in operation the light modulator directs at least one of the WDM channels into the second mode while directing a remainder of the WDM channels into the first mode; a collimation lens coupling the input to the diffraction grating; and a mirror coupled to the diffraction grating such that in operation the diffraction grating disperses the WDM channels into the range of angles in a first pass of the diffraction grating and further such that in operation the mirror returns the WDM channels to the diffraction grating where the WDM channels are further dispersed by the diffraction grating in a second pass of the diffraction grating before the WDM channels reach the grating light valve type device, wherein the input comprises an optical fiber coupled to a circulator, and wherein the output comprises a reverse path from the grating light valve type device to the circulator via the transform lens, the diffraction grating, and the collimation lens.