Ion mobility spectrometer with non-radioactive ion source
AssigneeBruker Saxonia Analytik GmbH
InventorHans-Rüdiger Döring
Life of this patent
Estimating the term…
Abstract
An ion mobility spectrometer (IMS) is provided that has a non-radioactive electron source in an evacuated chamber that is separated from the reaction chamber of the IMS by an x-ray window. Electrons from the source impinge upon an x-ray anode, causing the emission of x-ray radiation toward the window. A current controller is provided by which currents in the electron-source chamber are monitored and controlled using a microprocessor circuit. If a maximum permissible residual gas pressure is exceeded, the electron source is automatically shut down and a gettering process is activated.
Claims18
An ion mobility spectrometer comprising:
- an evacuated electron-source chamber;
- a reaction chamber separated from the electron source chamber by a gas-tight x-ray window that is substantially impermeable to electrons generated by the electron source;
- a non-radioactive electron source and an x-ray anode located within the chamber such that electrons from the electron source impinge upon the anode to cause x-ray radiation to be generated toward the window;
- a current controller including a control circuit and a control electrode that is located between the electron source and the anode, the controller regulating anode current by monitoring the anode current with the control circuit and controlling the voltage on the control electrode in response thereto;
- and
- a getter located in the electron-source chamber, activation of the getter being electrically controlled by the control circuit.
An ion mobility spectrometer comprising:
- an evacuated electron-source chamber;
- a reaction chamber separated from the electron-source chamber by a gas-tight x-ray window that is substantially impermeable to electrons generated by the electron source;
- a non-radioactive electron source located within the chamber which is connected to the negative pole of an accelerating voltage source;
- an x-ray accelerating anode located within the chamber which is connected to the positive pole of the accelerating voltage source, the source and anode being such that electrons from the electron source impinge upon the anode and cause x-ray radiation to be emitted toward the window;
- a current controller including a control circuit and a control electrode that is located between the electron source and the anode, the controller regulating anode current by monitoring the anode current with the control circuit and controlling the voltage on the control electoron in response thereto;
- a monitoring circuit that monitors the anode current between the positive and negative pole during operation and a safety circuit that shuts down the electron source if a fault current between the anode and the control electrode exceeds a specified limit;
- and
- at least one getter pearl located in the electron-source chamber, the getter pearl having an activating heater that may be electrically controlled.
Dependencies are inferred from the claim text.