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:
Nov. 21, 2000
Filed:
May. 04, 1999
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A precision polishing apparatus has a first hermetically sealed chamber provided with polishing means, a third hermetically sealed chamber capable of communicating with the first hermetically sealed chamber through a second hermetically sealed chamber, first and second opening-closing means for alternately placing the first and the third hermetically sealed chamber in communication with the second hermetically sealed chamber, and atmosphere pressure control means for controlling the atmosphere pressure of the first and the second hermetically sealed chamber so that the atmosphere pressure of the first hermetically sealed chamber may become lower than the atmosphere pressure of the second hermetically sealed chamber when at least the first opening-closing means is opened.