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, 2002
Filed:
May. 24, 1999
Baoliang Wang, Forest Grove, OR (US);
Theodore C. Oakberg, Forest, OR (US);
Paul Kadlec, Forest Grove, OR (US);
Hinds Instruments, Inc., Hillsboro, OR (US);
Abstract
A practical system and method for precisely measuring low-level birefrigence properties (retardance and fast axis orientation) of optical materials ( ). The system permits multiple measurements to be taken across the area of a sample to detect and graphically display ( ) variations in the birefrigence properties across the sample area. In a preferred embodiment, the system incorporates a photoelastic modulator ( ) for modulating polarized light that is then directed through a sample ( ). The beam (“Bi”) propagating from the sample is separated into two parts, with one part (“B ”) having a polarization direction different than the polarization direction of the other beam part (“B ”). These separate beam parts are then processed as distinct channels. Detection mechanisms ( ) associated with each channel detect the time varying light intensity corresponding to each of the two parts of the beam. The information is combined for calculating a precise measure of the retardance induced by the sample, as well as the sample's fast axis orientation.