Patent ID: 7132640
Filing Date: 2006-11-07
Classification: G01N

Abstract:
1. A method for detecting at least one anomaly on a target substrate having a substantially planar surface, comprising: a) providing an array of resonant photonic open-feed antenna elements spaced apart from one another and arranged in a plane substantially parallel to the surface of the target substrate; b) directing an incident energy beam of coherent light from an energy source toward the target substrate, the energy beam having an characteristic wavelength (λ), so that the energy beam is scattered by the anomaly and the array of antenna elements; c) re-radiating, by at least one of the antenna elements, energy scattered by the at least one anomaly on the target substrate; d) providing a holographic filter corresponding to energy scattered by the array of antenna elements when no anomaly is present on the target substrate; e) filtering the scattered and re-radiated energy using at least the holographic filter to produce a filtered result corresponding to the energy scattered by the at least one anomaly; and f) determining from the filtered result whether the at least one anomaly is present on the substrate.