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:
Jun. 21, 2005
Filed:
Jul. 02, 2002
Masaaki Nakabayashi, Kanagawa, JP;
Masaaki Nakabayashi, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
The object of this invention is to provide a mold releasing method for a diffraction optical element, which enables stable mass production of a diffraction optical element free from deformation or damage due to mold release. In order to achieve this object, a mold releasing method for a diffraction optical element, of releasing from a mold a diffraction optical element formed by using the mold and having a convex lens function, includes the steps of pressing a central portion of the diffraction optical element toward the mold, and pushing a periphery of the diffraction optical element in a direction to separate from the mold, so that mold release progresses from the periphery toward the central portion of the diffraction optical element. The method also includes the step of adjusting the balance with a plurality of hydraulic cylinders without pressing the central portion, so that mold release progresses toward the center.