05093680 is referenced by 32 patents and cites 26 patents.

An image magnification control device for a camera. Control focal length required to maintain an image magnification constant is computed based upon defocus information detected by analyzing a light that passes through a photographic lens. In case a focal length of the photographic lens moves out of a range wherein the set image magnification can be obtained, various options, such as a shutter-release lock operation, can be executed depending upon the chosen design of the camera.

Title
Image magnification control device for a camera
Application Number
7/410880
Publication Number
5093680
Application Date
September 22, 1989
Publication Date
March 3, 1992
Inventor
Masahiro Kawasaki
Saitama
JP
Shigeo Toji
Tokyo
JP
Noboru Suzuki
Tokyo
JP
Agent
Sandler Greenblum Bernstein
Assignee
Asahi Kogaku Kogyo Kabushiki Kaisha
JP
IPC
G03B 13/00
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