Optical transversal filter

Abstract

An optical transversal filter includes a processing system having a light source adapted to be modulated by an input electromagnetic signal and generate a plurality of collimated optical signals, a cascade of optical time delay units sequentially coupled to act upon the collimated optical signals passing from the light source to selectively differentially time delay respective ones of the optical signals, an optical trimmer device coupled to receive the differentially time delayed optical signals and to selectively attenuate respective ones of those signals, and a filter output assembly which receives and sums the optical signals from the trimmer device optically and converts the sum to a corresponding filtered electrical signal, or alternatively, converts the respective optical signals to electrical signals and electrically sums the signals. Each optical time delay unit includes a spatial light modulator having liquid crystal pixels disposed such that the polarization orientation of each respective optical signal is controlled by passing respective optical signals through respective ones of the pixels. Dependent on its polarization orientation, each optical signal passes through a delay assembly optically coupled to the respective spatial light modulator in the optical time delay unit on either a direct path or a delay path.

Dependencies are inferred from the claim text.