Close-up changeover device of zoom lens

Abstract

Abstract PURPOSE: To obtain a close-up, with the second lens stopped, by drawing back the third lens only, by providing a U-shaped guide hole in a fixed barrel, and providing guide holes for second and thired lenses and a V-shaped guide hole for turning in a rotating lens barrel. CONSTITUTION: A U-shaped guide hole 5 is provided in a fixed barrel, and second lens guide holes 6, 7, third lens guide holes 8, 9, and a V-shaped guide hole 10 are provided in a rotating lens barrel 4. A stepped protuberance 11 of an operation barrel 1 is inserted into the guide hole 10 through the guide hole 5. In this setup, therefore, when the operation barrel 1 is drawn back to the limit for close-up, the second lens 12 fitted in an extended part 7 of the guide hole 6 does not move, and only the third lens 13 fitted in an extended part 9 of the guide hole 8 retreats, so that close-up may be obtained without requiring attachment lens 3. In addition, only by turning the operation barrel 1 right and left, variable magnification and close-up can be changed over. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Nobuo Iwaoka

Bibliographic Details