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. 29, 2013
Filed:
Jun. 20, 2011
Johannes D. DE Veer, Menlo Park, CA (US);
Leonid Poslavsky, Belmont, CA (US);
Guorong V. Zhuang, Santa Clara, CA (US);
Shankar Krishnan, Santa Clara, CA (US);
Johannes D. de Veer, Menlo Park, CA (US);
Leonid Poslavsky, Belmont, CA (US);
Guorong V. Zhuang, Santa Clara, CA (US);
Shankar Krishnan, Santa Clara, CA (US);
KLA-Tencor Corporation, Milpitas, CA (US);
Abstract
A method to calibrate a polarizer in polarized optical system at any angle of incidence, by decoupling the calibration from a polarization effect of the system, by providing a calibration apparatus that includes a substrate having a polarizer disposed on a surface thereof, with an indicator on the substrate for indicating a polarization orientation of the polarizer, loading the calibration apparatus in the polarized optical system with the indicator in a desired position, determining an initial angle between the polarization orientation and a reference of the polarized optical system, acquiring spectra using the polarized optical system at a plurality of known angles between the polarization orientation and the reference of the polarized optical system, using the spectra to plot a curve indicating an angle of the polarizer in the polarized optical system, and when the angle of the polarizer is outside of a desired range, adjusting the angle of the polarizer, and repeating the steps of acquiring the spectra, and plotting a curve indicating the angle of the polarizer.