Abstract: Techniques for performing optical proximity correction on a layout design or portion thereof are provided with various implementations of the invention. With various implementations of the invention, movement and simulation of selected edge fragments is disabled during the optical proximity correction process. The operations of the optical proximity correction process, such as for example simulation and displacement of edge segments, is then performed for the edge fragments that remain enabled. With further implementations of the invention, a simulation site is defined for ones of the edge fragments. The operations of the optical proximity correction process, such as for example simulation and displacement of edge segments, is performed for each simulation site. Additionally, during the optical proximity correction process, the simulations sites may be moved and or removed individually based on various conditions.

Abstract: The present invention relates to a method for finding design weakness and potential field failure of a PCB assembly which includes components, comprising the steps of: (a) creating a model of the PCB assembly by which natural frequencies and mode shapes of the PCB assembly can be determined; (b) performing a natural frequencies simulation for determining natural frequencies and mode shapes of the PCB assembly; and (c) analyzing said determined natural frequencies and mode shapes and identifying local dominant oscillations of components, components identified as having a local dominant oscillation in at least one of said determined mode shapes are identified as components having a relatively high potential of field failure.