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. 20, 2001
Filed:
Mar. 31, 2000
Nikon Corporation, Tokyo, JP;
Abstract
A method is provided for evaluating a transmittance of an optical member for ultraviolet use, which is an object of measurement. The method includes the steps of cleaning the object of measurement, measuring a transmittance of the object of measurement within a predetermined time period from completion of the cleaning during which a rate of decrease in the transmittance of the object of measurement remains substantially constant, and correcting the transmittance measured in the step of measuring to a transmittance at an evaluation time arbitrarily selected within the predetermined time period in accordance with the constant rate of decrease in the transmittance and a time at which the transmittance is measured.