Wave transmission lines and networks – Coupling networks – Electromechanical filter
Patent
1993-08-02
1995-01-17
Gensler, Paul
Wave transmission lines and networks
Coupling networks
Electromechanical filter
310344, H03H 917
Patent
active
053829298
ABSTRACT:
A monolithic crystal filter includes a crystal plate sealed airtight in a vessel. The vessel consists of a metal lid and a main body. The crystal plate is supported a predetermined distance from an insulating substrate. An input electrode and an output electrode are affixed to one surface of the crystal plate. A common electrode is affixed to the other surface of the crystal plate. The insulating substrate has a shield electrode thereon facing the input electrode and output electrode. The shield electrode is grounded to the metal lid of the vessel. An optimal distance between the shield electrode and the input electrode and the output electrode is disclosed for obtaining the best stopband attenuation level. An aluminum electrode island between the crystal plate and an electrode terminal develops an oxide coating which permits relaxation of stress and strain between the electrode island and its associated input and output electrodes to the resulting appropriate bonding strength therebetween. This maintains good frequency/temperature stability of the monolithic crystal filter. Adhesive is applied to one side of the electrode island, overlapping both the electrode island and the crystal plate, to maintain a low value of stress at one side and to maintain proper electric conductivity and raise the shock resistance at the other side.
REFERENCES:
patent: 4511821 (1985-04-01), Nakamura et al.
Inao Kiyohisa
Kumagai Masaki
Mizuki Koji
Seki Takeo
Gensler Paul
Gluck Peter J.
Kohli Vineet
NDK, Nihon Dempa Kogyo Company, Ltd.
LandOfFree
Monolithic crystal filter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Monolithic crystal filter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Monolithic crystal filter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-749655