公开(公告)号：US4918929A

公开(公告)日：1990-04-24

申请号：US200224

申请日：1988-05-31

Applicant: John S. Chudy ,  M. John Kniffin ,  D. Yvonne McNeil

Inventor： John S. Chudy ,  M. John Kniffin ,  D. Yvonne McNeil

IPC: F17C3/08 ,  F25D19/00 ,  G01J5/06 ,  G01J5/28

CPC classification number: F17C3/085 ,  F25D19/006 ,  G01J5/061 ,  G01J2005/286

Abstract: Consolidation of active and passive detectors (26, 28, 34) on a single coldfinger (20) in a dewar (10) is made possible by interposing between the detectors (26, 28, 34) an electromagnetic interference shield (64, 68) which acts as a waveguide filter blocking any interfering frequencies. The waveguide is formed by a pair of spaced interleaved shields (64, 68), one of which (64) is associated with the dewar envelope and is externally grounded, and the other of which is associated with the coldfinger (20). Photons which penetrate through the waveguide (64, 68) are deflected to the outside of the dewar (10) by a flanged narcissus shield (40) surrounding the passive detector (34). Alignment of the detectors (26, 28, 34) and assembly of the dewar (10) is greatly facilitated by constructing the envelope in several generally cylindrical sections (14, 16, 18), the lowermost one of which (14) is shorter than the coldfinger (20); and by fusing the coldfinger (20) and lowermost envelope section (14) to a metal mounting base (12) prior to the final assembly of the dewar (10).

Abstract translation: 通过在检测器（26,28,34）之间插入电磁干扰屏蔽（64,68），能够将主动和被动检测器（26,28,34）合并在杜瓦瓶（10）中的单个冷指针（20）上， 其作为阻挡任何干扰频率的波导滤波器。 波导由一对间隔开的交错屏蔽（64,68）形成，其中一个（64）与杜瓦封套相关联，并且外部接地，另一个与冷指针（20）相关联。 穿过波导（64,68）的光子被围绕无源探测器（34）的带凸缘的水仙屏蔽（40）偏转到杜瓦瓶（10）的外部。 探测器（26,28,34）的对准和杜瓦瓶（10）的组装通过在几个大致圆柱形部分（14,16,18）中构造外壳而极大地促进，其中最下面的（14）短于 冷指甲（20）; 以及在所述杜瓦瓶（10）的最终组装之前将所述冷指针（20）和所述最低包络部分（14）熔合到金属安装基座（12）。