The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 2018
Filed:
Aug. 03, 2016
Neal Brock, Tucson, AZ (US);
Goldie Goldstein, Tucson, AZ (US);
Brad Kimbrough, Tucson, AZ (US);
Erik Novak, Tucson, AZ (US);
James Millerd, Tucson, AZ (US);
Neal Brock, Tucson, AZ (US);
Goldie Goldstein, Tucson, AZ (US);
Brad Kimbrough, Tucson, AZ (US);
Erik Novak, Tucson, AZ (US);
James Millerd, Tucson, AZ (US);
AD TECHNOLOGY CORPORATION, Tucson, AZ (US);
Abstract
A cycloidal diffraction waveplate is combined with a pixelated phase mask (PPM) sensor in a dynamic fringe-projection interferometer to obtain phase-shifted interferograms in a single snap-shot camera operation that provides the phase information required to measure test surfaces with micrometer precision. Such mode of operation enables a portable embodiment for use in environments subject to vibration. A shifting mechanism coupled to the cycloidal waveplate allows temporal out-of-phase measurements used to remove noise due to test-surface characteristics. Two or more pixels of each unit cell of the PPM are combined to create super-pixels where the sum of the phases of the pixels is a multiple of 180 degrees, so that fringes are eliminated to facilitate operator focusing. By assigning colors or cross-hatch patterns to different ranges of modulation measured at the detector, the areas of best focus within the field of view are identified quantitatively to ensure measurements under best-focus conditions.