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:
Oct. 16, 2012
Filed:
Sep. 17, 2009
Seung-yop Lee, Seoul, KR;
Kyoung Up Kim, Seoul, KR;
Jae Hyun Kim, Seoul, KR;
Kyuman Cho, Seoul, KR;
Young Kyu Park, Incheon, KR;
Seung-Yop Lee, Seoul, KR;
Kyoung Up Kim, Seoul, KR;
Jae Hyun Kim, Seoul, KR;
Kyuman Cho, Seoul, KR;
Young Kyu Park, Incheon, KR;
Abstract
Disclosed herein is an apparatus and method which is capable of accurately measuring surface status, such as a minute variation in height (the height difference), a protrusion, a depression, surface damage and/or surface roughness, at each point on the surface of the object to be measured in an optical manner. In particular, the present invention provides an optical surface measuring apparatus and method which is capable of accurately measuring the minute surface status of the object to be measured using both a signal from an interferometer and a Focus Error (FE) signal from a Position Sensitive Detector (PSD) in order to overcome the 2π-ambiguity of the conventional interferometers and the limitation of the Focus Error (FE) signal.