专利检索 ap:("RANK PRECISION IND LTD") AND inv:"BARR JOHN DENZIL" 第 1 页

1.

发明授权
Control devices for optical objectives of variable equivalent focal length 失效
标题翻译：用于可变等效焦点长度的光学目标的控制装置

公开(公告)号：US3558217A

公开(公告)日：1971-01-26

申请号：US3558217D

申请日：1968-06-26

申请人： RANK PRECISION IND LTD

发明人： BARR JOHN DENZIL , PLUMMER DEXTER ROBERT

IPC分类号： G02B7/08 , G02B7/10 , G02B15/14 , G02B27/40 , G03B17/14 , G05D3/14 , G02B15/00

CPC分类号： G05D3/1409 , G02B7/08 , G02B7/10 , G02B15/14 , G02B27/40 , G03B17/14 , G05D3/14

摘要： CONTROL DEVICE FOR ZOOM OBJECTIVES HAVING FOCUSSING CONTROLS, SAID DEVICE COMPRISING A MECHANICAL OR HYDRAULIC VARIABLE RATIO TRANSMISSION, AND MECHANICAL MEANS THROUGH WHICH THE RATIO OF SAID TRANSMISSION IS VARIED BY MOVEMENT OIF THE ZOOM CONTROL ELEMENT TO MAINTAIN THE APPARENT SENSITIVITY OF THE FOCUSSING CONTROL WITHIN PREDETERMINED LIMITS.