US 7,622,713 B2 · Method and apparatus for normalizing performance of an electron source

Abstract

A method for operating a mass spectrometer includes determining a first performance characteristic while operating the mass spectrometer with a first electron emitter, storing first information relating to the first performance characteristic, determining a second performance characteristic while operating the mass spectrometer with a second electron emitter, storing second information relating to the second performance characteristic, and thereafter switching from operation using the first electron emitter to operation using the second electron emitter. The switching includes using the first and second information to normalize performance of the second electron emitter after the switching relative to performance of the first electron emitter before the switching.

Claims22

Dependent claims

A method for operating a mass spectrometer having first and second electron emitters, the method comprising:

determining a first performance characteristic while operating the mass spectrometer with the first electron emitter;
storing first information relating to the first performance characteristic;
determining a second performance characteristic while operating the mass spectrometer with the second electron emitter;
storing second information relating to the second performance characteristic;
and
thereafter switching from operation using the first electron emitter to operation using the second electron emitter, wherein the switching includes using the first and second information to normalize performance of the second electron emitter after the switching relative to performance of the first electron emitter before the switching.

3 more elements

An apparatus comprising a mass spectrometer that includes:

structure defining an ion volume;
first and second electron emitters that can each selectively supply electrons to the ion volume;
and
a controller configured to:
determine a first performance characteristic while operating the mass spectrometer with the first electron emitter;
store first information relating to the first performance characteristic;
determine a second performance characteristic while operating the mass spectrometer with the second electron emitter;
store second information relating to the second performance characteristic;
and
thereafter switch from operation using the first electron emitter to operation using the second electron emitter, including use of the first and second information to normalize performance of the second electron emitter after the switch relative to performance of the first electron emitter before the switch.

7 more elements

Dependencies are inferred from the claim text.

Method and apparatus for normalizing performance of an electron source

Life of this patent

Method and apparatus for normalizing performance of an electron source

Life of this patent

Abstract

Claims22