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:
Jan. 07, 1997
Filed:
Jan. 19, 1995
Toshihiko Tsuji, Utsunomiya, JP;
Michio Kohno, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A surface state inspecting system includes a scanning optical system for scanning a surface to be inspected, with first light and simultaneously for scanning a diffraction grating with second light, wherein the first light and the second light have mutually different wavelengths and mutually different polarization directions, a light receiving optical system for receiving scattered light produced sidewardly from the surface and diffraction light produced sidewardly from the diffraction grating, and for superposing the received lights one upon another, and a photoelectric converting device for converting light from the light receiving optical system into an electric signal, wherein the scanning optical system and the light receiving optical system provide an optical system which is telecentric with respect to the surface to be inspected.