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:
Aug. 03, 2004
Filed:
Apr. 08, 2003
Hiroshi Anzai, Nihonmatsu, JP;
Hirokazu Yamamoto, Fujisawa, JP;
NOK Corporation, Tokyo, JP;
Abstract
In a housed state, a magnetic fluid is positioned in a groove and spaced from the outer circumference of a lens barrel , so that a fluorochemical surface modification film of the outer circumference of the lens barrel can be prevented from deteriorating at a position to confront the magnetic fluid in the housed state. Therefore, the deterioration of the fluorochemical surface modification film of the outer circumference of the lens barrel does not proceed earlier at a local region, so that the premature wetting of the outer circumference of the lens barrel with the magnetic fluid can be prevented to elongate the lifetime of a light shielding device