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. 28, 1994
Filed:
Feb. 14, 1992
Masaru Takashima, Tokyo, JP;
Tatsuru Kanamori, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
The present invention relates to a compact zoom lens system having a long back focus and a zoom ratio of about 1.7, which comprises a first lens unit G1 having a positive focal length, a second lens unit G2 having a positive focal length and a third lens unit G3 having a negative focal length, said first, second and third lens units G1, G2 and G3 being all movable toward the object side during zooming from the wide angle to telephoto side such that the first and second lens units G1 and G2 are spaced away from each other, while the second and third lens units G2 and G3 are moved toward each other, and is characterized by conforming to the following conditional formula: