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:
Mar. 22, 2011
Filed:
Sep. 30, 2008
Tsuneo Terasawa, Tokyo, JP;
Toshihiko Tanaka, Tokyo, JP;
Tatsuya Aota, Hyogo, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
The mask blank inspection apparatus is constituted of a stage for mounting a reflective mask blank thereon, a light source for generating inspection light, a mirror serving as an illuminating optics, an imaging optical system, a beam splitter, two two-dimensional array sensors, signal storage units, an image processing unit, a main control unit for controlling operation of the whole apparatus, the first sensor being located at a position which is displaced by a predetermined distance from the focal plane of a first light beam, the second sensor being located at a position which is displaced by a predetermined distance from the focal plane of a second light beam along a opposite direction, whereby accurately and conveniently inspecting presence/absence and types of defects in reflective mask blank.