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Title:
【発明の名称】変倍ファインダー
Document Type and Number:
Japanese Patent JP3330660
Kind Code:
B2
Abstract:
A zoom finder has first to third lens groups sequentially arranged from an object side to an eye pupil side and performs a zooming operation by fixing the first and third lens groups and moving the second lens group. The first lens group is constructed by a positive single lens. The second lens group is constructed by a negative single lens. The third lens group has a positive combinational focal length and is constructed by a negative single lens arranged on the object side and a positive single lens arranged on the eye pupil side. A frame system of the zoom finder is formed by an eye pupil side lens face of the negative single lens of the third lens group and the positive single lens of the third lens group. Radii R1 and R2 of curvature of lens faces of the first lens group on the object and eye pupil sides satisfy the following condition.0.8

Inventors:
Shuyuki Iwata
Yoshiko Shimada
Application Number:
JP1531593A
Publication Date:
September 30, 2002
Filing Date:
February 02, 1993
Export Citation:
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Assignee:
株式会社リコー
International Classes:
G02B13/18; G02B15/14; G02B15/173; G02B25/00; G03B13/12; (IPC1-7): G02B15/14; G02B13/18; G02B25/00; G03B13/12
Domestic Patent References:
JP4163511A
JP1182817A
JP2116811A
JP566347A
JP6187122A
JP61160712A
JP625212A
Attorney, Agent or Firm:
Toru Kabayama (1 person outside)



 
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