Patent ID: 6819432
Filing Date: 2004-11-16
Classification: H04B

Abstract:
An optical apparatus for coherent detection of an input optical beam, the apparatus comprising:(a) a beam splitter for splitting the input optical beam into a first component and a second component, the optical beam having information content with a minimum signal frequency component; (b) an optical delay device arranged to receive the second component, the optical delay device imposing an intentional delay in the second component of the input optical beam; (c) an adaptive beam combiner coupled to receive (i) the second component with a delay imposed thereon by the optical delay device; and (ii) the first component from the beam splitter; the adaptive beam combiner having two exiting optical components having the same wavefronts and propagating directions as the first and second components and being in quadrature; and (d) a detector arrangement for receiving and detecting the first and second exiting components from the adaptive beam combiner.