Microwave cavity resonator for continuous spectroscopic gas analysis

US5949237A · kind A · utility

Assignee

• Forschungszentrum Karlsruhe GmbH · DE

Inventors

• Lutz-Michael Berger · Dresden, DE
• Franz Koniger · Bischwiller, FR
• Hans-Dieter Metzger · Karlsruhe, DE
• Gerhard Schmitt · Bensheim, DE

Key dates

• Filing date: Jul 15, 1998
• Grant date: Sep 7, 1999
• Expiry date: Jul 15, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N22/00
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

In a microwave resonator for continuous spectroscopic gas analysis with a microwave cavity having dimensions depending on the operating frequency and a setting for a low quality Q of its base mode and microwave reflectors disposed at its opposite ends and including a round hollow conductor part and a co-axial conductor part separated by a pressure-tight dielectric window, an internal conductor part is axially movably supported in the coaxial conductor part by the microwave reflector at one end of the co-axial conductor part, the other reflector being axially movable for tuning the resonator to a maximal absorption frequency and a by-pass line extends past the co-axial conductor part in the area of the dielectric window and has a short branch connected to the co-axial conductor part and including a restrictor for supplying only a relatively small flow of gas from the bypass line to the conductor part of the microwave resonator.