Patent search ap:("EDWARD A JOHNSON") AND inv:"CALLAHAN CHARLES J" Page 1

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发明授权
Lens mounting 失效
Title translation: 镜头安装

公开(公告)号：US2071331A

公开(公告)日：1937-02-23

申请号：US130535

申请日：1935-01-11

Applicant: EDWARD A JOHNSON

Inventor： CALLAHAN CHARLES J

IPC: G02C5/00 , G02C5/04

CPC classification number: G02C5/006 , G02C5/04

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