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. 17, 1987
Filed:
Jan. 29, 1986
Yoshinori Shimamura, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An exposure apparatus for exposing a first object to a radiation energy passed through a second object, having a pattern, thereby to transfer the pattern of the second object onto the first object, the exposure apparatus including a radiation energy source, at least one spare radiation energy source and an arrangement for substituting the first-mentioned radiation energy source by the second-mentioned, spare, radiation energy source when the service life of the first-mentioned radiation energy source becomes over or nearly over, wherein the spare radiation energy source is energized or actuated when the intensity of irradiation of the first-mentioned radiation energy source is decreased to a predetermined value and, at the same time or after elapse of a predetermined time, the first-mentioned radiation energy source is sustituted by the spare radiation energy source.