Focusing device of zoom lens

Abstract

Abstract PURPOSE:To improve the precision of setting greatly by setting the movement amount of a focusing lens group on the basis of the defocusing amount of a subject image and the magnification and focal length of a variable magnification lens group at this time. CONSTITUTION:This is a focusing device which adjusts the focus of a zoom lens Z by detecting the defocusing amount DELTAP of the subject image and zoom information N on the zoom lens Z, and the magnification (m) and focal length fe of the variable magnification lens group E are preset corresponding to the zoom information N. Then, the movement amount DELTAx of the focusing lens group A is set on the basis of the defocusing amount DELTAP, the magnification (m) and focal length fe of the variable magnification lens group E.

Inventors

• 👤 Eiji Kikko
• 👤 英治 橘高
• 👤 Mineo Kubota
• 👤 窪田　峰夫

Bibliographic Details