Optical system for deflecting image
AssigneeCanon Kabushiki Kaisha
InventorsNozomu Kitagishi, Shoichi Yamazaki
Life of this patent
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Abstract
An optical system for deflecting an image by decentering a portion of a photographic lens in a direction perpendicular to an optical axis, wherein the decentering aberrations produced by the decentering are reduced.
Claims16
An optical system for correcting image blurring comprising, from front to rear, a fixed lens unit stationary relative to a direction perpendicular to the optical axis, and a movable lens unit with means for moving said movable lens unit in a direction having a directional component transverse to the optical axis to stabilize an image, said movable lens unit including a plurality of lenses, and satisfying the following condition:
- 0.05<L.sub.2 /F <0.4
- where L.sub.2 is the length from a frontmost lens surface in said movable lens unit to a rearmost lens surface therein, and F is the focal length of the entire lens system.
A photographic optical system comprising a fixed lens unit stationary relative to a direction perpendicular to the optical axis, and a movable lens unit arranged on the image side of said fixed lens unit with means for moving said movable lens unit in a direction having a directional component transverse to the optical axis to deflect an image, said movable lens unit including a positive lens and a negative lens, and satisfying the following condition:
- .sub.p.nu..sub.d >75
- 0.525<.sub.p .theta..sub.g,F <0.545
- where .sub.p .theta..sub.d and .sub.p .theta..sub.g,F are the Abbe number and the partial dispersion ratio of said positive lens respectively, wherein a partial dispersion ration .theta..sub.g,F is defined by an equation:
- .theta..sub.g,f =(n.sub.g -n.sub.F)/(n.sub.F -n.sub.C) wherein n.sub.g, n.sub.F and n.sub.C are the refractive indices for the spectral g-line, F-line and C-line, respectively.
A photographic lens having an optical axis, comprising a movable lens unit and means for moving said movable lens unit in a direction having a directional component transverse to the optical axis to deflect an image, and light limiting means movable in a direction perpendicular to the optical axis in synchronism with movement of said movable lens unit and having a limiting portion for limiting light.
Dependencies are inferred from the claim text.