Ablated laser feature shape reproduction control

Abstract

This invention concerns a process useful for increasing the accuracy of the shape of a laser ablated feature formed on a substrate, especially where the substrate is a polymeric article. The process includes irradiating the polymeric article with laser light that has passed through a retardation plate selected from stationary adjustable plates, rotating plates or spinning plates, preferable in multiples of quarter-waves or half-waves. This invention also concerns a laser apparatus useful for making ablated features in a substrate having a radiation source; a mask positioned between the radiation source and a substrate to be irradiated, and a retardation plate which is stationary and adjustable, rotating or spinning plates.

Dependencies are inferred from the claim text.