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:
Jan. 29, 2002
Filed:
Apr. 21, 2000
Takanori Yamanashi, Kokubunji, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A wide-angle zoom lens system having a short optical total length not only at the wide-angle end but also at the telephoto end and a reduced telephoto ratio despite the fact that it has a high zoom ratio, with a view to achieving a reduction in size of cameras. The zoom lens system has a first lens unit G of positive refractive power, a second lens unit G of negative refractive power, a third lens unit G of positive refractive power, and a fourth lens unit G of negative refractive power. When the zoom lens system is zoomed from the wide-angle side to the telephoto side, each of the lens units moves toward the object side such that the space between the first lens unit G and the second lens unit G increases, whereas the space between the third lens unit G and the fourth lens unit G decreases. The zoom lens system satisfies a condition concerning the focal lengths of the first lens unit G and the fourth lens unit G , a condition concerning the amount of movement of the fourth lens unit G and a condition concerning the zoom ratio assigned to the fourth lens unit G