Patent ID: 6266141
Filing Date: 2001-07-24
Classification: G01J,G01M,G01N

Abstract:
A birefringence measuring apparatus comprising:a radiation optical system configured to radiate diffusion light onto a detection lens in a predetermined polarization state;a displacement medium configured to move and adjust a position of said radiation optical system in a direction of an optical axis with respect to said detection lens;a polarization element configured to change the polarization state of transmission light transmitted from said detection lens;a rotation angle detection medium configured to detect an angle of rotating said polarization element;an array-state light-receiving element configured to receive light transmitted through said polarization element;a focusing optical system configured to focus the light transmitted through said polarization element on said array-state light-receiving element; andan operational calculation medium configured to calculate birefringence of said detection lens based on the rotation angle detected by said rotation angle detecting medium and an output of the light focused on said array-state light-receiving element.