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. 09, 2017
Filed:
Aug. 18, 2014
National Tsing Hua University, Hsinchu, TW;
Wei-Chung Wang, Hsinchu, TW;
Chi-Hung Huang, Taichung, TW;
Po-Chi Sung, Hsinchu, TW;
Meng-Hsiu Li, Hsinchu, TW;
NATIONAL TSING HUA UNIVERSITY, Hsinchu, TW;
Abstract
A device for real-time thickness inspection is provided. An optical interferometric technique is used. Measurement requirements in rapid online thickness inspection can be satisfied. An object is measured in a non-contact and non-destructive way. For measuring, an optical spherical wavefront is radiated on the object in an oblique angle. The interference fringe pattern (IFP) thus imaged on a screen is directly related to the thickness distribution of the object. The phase difference on the same horizontal cross section in the IFP monotonically decreases from the light source side to the other side. Accordingly, phase unwrapping can be effectively performed without using phase shift. The present invention achieves rapid on-line thickness inspection through the optical path of interference without using optical lens groups and special optical elements. The present invention radiates a high-coherence point-expanded spherical-wavefront light beam in an oblique angle for an instantaneous and wide-area full-field thickness measurement.