ALEXANDRIA, Va., June 25 -- United States Patent no. 12,339,235, issued on June 24, was assigned to Onto Innovation Inc. (Wilmington, Mass.).
"Simultaneous back and/or front and/or bulk defect detection" was invented by Felix Moellmann (Zurich), Mark Varner (Snoqualmie, Wash.) and Andrew Phillip Frazier (Snoqualmie, Wash.).
According to the abstract* released by the U.S. Patent & Trademark Office: "An inspection system for inspecting multiple surfaces of a substrate includes at least one illuminator that produces light at a first wavelength that is incident on the substrate at a first angle (e.g., normal) and light at a second wavelength directed that is obliquely incident on the substrate. An adjustment system adjusts the oblique angle. ...