Patent ID: 9097683
Filing Date: 2015-08-04
Classification: C03B,C30B,G01N,G02F,H01S

Abstract:
1. An optical system for detecting contaminants and defects on a test surface, the optical system comprising: a laser system for producing a laser beam; optics directing the laser beam along a path onto the test surface, and producing an illuminated spot thereon; a detector detecting light; and an ellipsoidal mirrored surface, the mirrored surface and detector having an axis of symmetry about a line perpendicular to the test surface, the mirrored surface defining an input aperture positioned proximate to the test surface to receive scattered light therethrough from the surface and an exit aperture, the mirrored surface being substantially rotationally symmetric about the axis of symmetry, so that the mirrored surface reflects and focuses rotationally symmetrically about the axis of symmetry light that passes through the input aperture to the detector, the exit aperture being located opposite to the input aperture, wherein the laser system comprises: