-
公开(公告)号：US1981652A
公开(公告)日：1934-11-20
申请号：US53357731
申请日：1931-04-28
Applicant: BELL TELEPHONE LABOR INC
Inventor： LONG GEORGE E
IPC: H01J19/00
CPC classification number: H01J19/00 , H01J2893/0023
Search Results
1
records
(took 0.011 seconds)
筛选
AND
AND
过滤
NOT
NOT
Scan to Join
