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:
Aug. 15, 2017
Filed:
May. 03, 2016
Mitutoyo Corporation, Kanagawa-ken, JP;
Robert Kamil Bryll, Bothell, WA (US);
Mitutoyo Corporation, Kanagawa-ken, JP;
Abstract
A variable focal length (VFL) lens system is utilized to determine surface Z-height measurements of imaged surfaces. A controller of the system is configured to control a VFL lens (e.g., a tunable acoustic gradient index of refraction lens) to periodically modulate its optical power and thereby periodically modulate a focus position at a first operating frequency, wherein the periodically modulated VFL lens optical power defines a first periodic modulation phase. A phase timing signal is synchronized with a periodic signal in the controller that has the first operating frequency and that has a second periodic modulation phase that has a phase offset relative to the first periodic modulation phase. A phase offset compensating portion is configured to perform a phase offset compensating process that provides Z-height measurements, wherein at least one of Z-height errors or Z-height variations that are related to a phase offset contribution are at least partially eliminated.