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. 13, 2017
Filed:
Dec. 10, 2014
Tamron Co., Ltd., Saitama-shi, Saitama, JP;
Takahiko Sakai, Saitama, JP;
TAMRON CO., LTD., Saitama-shi, JP;
Abstract
An inner focus lens includes sequentially from an object side, a first lens group having a positive refractive power; a second lens group having a negative refractive power; and a third lens group having a negative refractive power. The second lens group is moved along the optical axis, whereby focusing from a focus state for an object at infinity to a focus state for a minimum object distance is performed. The inner focus lens satisfies a conditional expression (1) −29.0≦f3/f≦−5.4, where f3 is a focal length of the third lens group at the focus state for an object at infinity and f is a focal length of the optical system overall at the focus state for an object at infinity.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile