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:
Apr. 19, 2022
Filed:
Mar. 04, 2020
Ricoh Company, Ltd., Tokyo, JP;
Takahiro Nakayama, Kanagawa, JP;
Tomoya Koga, Tokyo, JP;
RICOH COMPANY, LTD., Tokyo, JP;
Abstract
A zoom lens satisfies Conditional Expression (1) as follows:−20<<1,  (1)Twt is a moving amount of the second lens group during zooming from the short focal-length end to the long focal-length end, a moving amount to the object side being indicated by a positive sign, a moving amount to an image side being indicated by a negative sign, andTwm is a moving amount of the second lens group during zooming from the short focal-length end to an intermediate focal length, a moving amount to the image side being indicated by a negative sign,the intermediate focal length being expressed by fm=(fw·ft), where fw is a focal length of a whole system at the short focal-length end, and ft is a focal length of the whole system at the long focal-length end.