Mass measurement system for mass spectrometers

Claim 1

In a system for determining mass of an ion in a scanning mass spectrometer by determining time of occurrence of a centroid of an output peak signal due to said ion with respect to time of occurrence of termination of said peak signal, the combination comprising: a. first integrating means for integrating said peak signal to obtain a first integral signal; b. second integrating means for integrating said first integral signal to obtain a second integral signal; c. dividing means for dividing said second integral signal by said first integral signal to provide a time signal proportional to the time of occurrence of said centroid relative to said time of occurrence of said termination of said peak signal. d. threshold detecting means for obtaining a termination signal indicating said termination of said peak signal; and, e. subtracting means for subtracting the value of said time signal from the value of said termination signal to obtain a signal having a value representative of said time of occurrance of said centroid.

Claim 15

A system for determining occurrence time of a time/amplitude centroid of a pulse signal having an amplitude above a threshold amplitude for a period of time comprising: a. first integrating means for integrating said pulse signal while its amplitude exceeds said threshold amplitude to provide a first integral signal; b. second integrating means for integrating said first integral signal while said amplitude of said waveform exceeds said threshold amplitude to provide a second integral signal; c. dividing means actuated after the amplitude of said pulse signal decreases to a value less than said threshold amplitude for dividing said second integral signal by said first integral signal to provide a signal representative of a period of time; and, d. subtracting means for subtracting said signal representative of a period of time from a signal representative of the time at which integration ceased due to amplitude of said waveform falling below said threshold amplitude to provide an output signal representative of the time of occurrence of the centroid.

Claim 16

A system for determining occurrence time of a time/amplitude centroid of a pulse signal having an amplitude above a threshold amplitude for a period of time comprising: a. first integrating means for integrating said pulse signal while its amplitude exceeds said threshold amplitude to provide a first integral signal; b. second integrating means for integrating said first integral signal while said amplitude of said waveform exceeds said threshold amplitude to provide a second integral signal; c. dividing means actuated after the amplitude of said pulse signal decreases to a value less than said threshold amplitude for dividing said second integral signal by said first integral signal to provide a signal representative of a period of time; and, d. subtracting means for subtracting said signal representative of a period of time from a signal representative of the time at which integration ceased due to amplitude of said waveform falling below said threshold amplitude to provide an output signal representative of the time of occurrence of the centroid.

Claim 33

A method of determining the time of occurrence of a time/amplitude centroid of a pulse signal having an amplitude above a threshold amplitude for a period Of time comprising the steps of: a. integrating said pulse signal while its amplitude exceeds said threshold amplitude to provide a first integral signal; b. integrating said first integral signal while the amplitude of the pulse signal exceeds said threshold amplitude to provide a second integral; c. dividing said second integral signal by said first integral signal after the amplitude of said pulse signal falls below said threshold amplitude to provide a signal representative of a period of time; and, d. subtracting said time representative signal from a signal representative of the time at which integration ceased due to amplitude of said pulse signal falling below said threshold amplitude to provide an output signal representative of the time of occurrence of the centroid.

Claim 34

A method of determining the time of occurrence of a time/amplitude centroid of a pulse signal having an amplitude above a threshold amplitude for a period Of time comprising the steps of: a. integrating said pulse signal while its amplitude exceeds said threshold amplitude to provide a first integral signal; b. integrating said first integral signal while the amplitude of the pulse signal exceeds said threshold amplitude to provide a second integral; c. dividing said second integral signal by said first integral signal after the amplitude of said pulse signal falls below said threshold amplitude to provide a signal representative of a period of time; and, d. subtracting said time representative signal from a signal representative of the time at which integration ceased due to amplitude of said pulse signal falling below said threshold amplitude to provide an output signal representative of the time of occurrence of the centroid.

Claim 35

A method of peak matching with a mass spectrometer comprising the steps of: a. establishing a field with an analyzer of the mass spectrometer; b. adjusting the level of the analyzer field such that ions of a first mass number are directed substantially toward an ion collector; c. scanning the level of the analyzer field over a range necessary to cause the waveform of a first output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; d. integrating said output signal during the scanning of the analyzer field to provide a first integral signal; e. integrating said first integral signal during the scanning of the analyzer field to provide a second integral signal; f. dividing said second integral signal by said first integral signal to provide a signal having a value representative of the elapsed time between the time of occurrence of a centroid of said first ion collector output signal and the termination of the scanning; g. adjusting the level of the analyzer field such that ions of a second mass number are directed substantially toward the ion collector; h. scanning the level of the analyzer field over a range necessary to cause the waveform of a second output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; i. integrating said second output signal during the second scanning of the analyzer field to provide a third integral signal; j. integrating said third integral signal during the second scanning of the analyzer field to provide a fourth integral signal; k. dividing said fourth integral signal by said third integral signal to provide another signal having a value representative of the elapsed time between the time of occurrence of a centroid of said second ion collector output signal and the termination of the second scanning; and, l. subtracting the value of one of said elapsed time representative signals from the value of the other elapsed time representative signal to provide a comparison signal representative of the relative positions of the signal peaks.

Claim 36

A method of peak matching with a mass spectrometer comprising the steps of: a. establishing a field with an analyzer of the mass spectrometer; b. adjusting the level of the analyzer field such that ions of a first mass number are directed substantially toward an ion collector; c. scanning the level of the analyzer field over a range necessary to cause the waveform of a first output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; d. integrating said output signal during the scanning of the analyzer field to provide a first integral signal; e. integrating said first integral signal during the scanning of the analyzer field to provide a second integral signal; f. dividing said second integral signal by said first integral signal to provide a signal having a value representative of the elapsed time between the time of occurrence of a centroid of said first ion collector output signal and the termination of the scanning; g. adjusting the level of the analyzer field such that ions of a second mass number are directed substantially toward the ion collector; h. scanning the level of the analyzer field over a range necessary to cause the waveform of a second output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; i. integrating said second output signal during the second scanning of the analyzer field to provide a third integral signal; j. integrating said third integral signal during the second scanning of the analyzer field to provide a fourth integral signal; k. dividing said fourth integral signal by said third integral signal to provide another signal having a value representative of the elapsed time between the time of occurrence of a centroid of said second ion collector output signal and the termination of the second scanning; and, l. subtracting the value of one of said elapsed time representative signals from the value of the other elapsed time representative signal to provide a comparison signal representative of the relative positions of the signal peaks.

Claim 39

A method of peak matching with a mass spectrometer comprising the steps of: a. establishing a field with an analyzer of the mass spectrometer; b. adjusting the level of the analyzer field such that ions of a first mass number are directed substantially toward an ion collector; c. scanning the level of the analyzer field over a range necessary to cause the waveform of a first output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; d. integrating said output signal during the scanning of the analyzer field to provide a first integral signal; e. integrating said first integral signal during the scanning of the analyzer field to provide a second integral signal; f. dividing said second integral signal by said first integral signal to provide a signal having a value representative of the elapsed time between the time of occurrence of a centroid of said first ion collector output signal and the termination of the scanning; g. adjusting the level of the analyzer field such that ions of a second mass number are directed substantially toward the ion collector; h. scanning the level of the analyzer field over a range necessary to cause the waveform of a second output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; i. integrating said second output signal during the second scanning of the analyzer field to provide a third integral signal; j. integrating said third integral signal during the second scanning of the analyzer field to provide a fourth integral signal; k. dividing said fourth integral signal by said third integral signal to provide another signal having a value representative of the elapsed time between the time of occurrence of a centroid of said second ion collector output signal and the termination of the second scanning; l. subtracting the value of one of said elapsed time representative signals from the value of the other elapsed time representative signal to provide a comparison signal representative of the relative positions of the signal peaks; m. changing the level of the analyzer field to a different value which also causes the ions of the first mass number to be directed substantially toward the ion collector; and, n. repeating the steps of c) through f) and h) through l) until the value of the comparison signal equals substantially zero.

Claim 40

A method of peak matching with a mass spectrometer comprising the steps of: a. establishing a field with an analyzer of the mass spectrometer; b. adjusting the level of the analyzer field such that ions of a first mass number are directed substantially toward an ion collector; c. scanning the level of the analyzer field over a range necessary to cause the waveform of a first output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; d. integrating said output signal during the scanning of the analyzer field to provide a first integral signal; e. integrating said first integral signal during the scanning of the analyzer field to provide a second integral signal; f. dividing said second integral signal by said first integral signal to provide a signal having a value representative of the elapsed time between the time of occurrence of a centroid of said first ion collector output signal and the termination of the scanning; g. adjusting the level of the analyzer field such that ions of a second mass number are directed substantially toward the ion collector; h. scanning the level of the analyzer field over a range necessary to cause the waveform of a second output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; i. integrating said second output signal during the second scanning of the analyzer field to provide a third integral signal; j. integrating said third integral signal during the second scanning of the analyzer field to provide a fourth integral signal; k. dividing said fourth integral signal by said third integral signal to provide another signal having a value representative of the elapsed time between the time of occurrence of a centroid of said second ion collector output signal and the termination of the second scanning; l. subtracting the value of one of said elapsed time representative signals from the value of the other elapsed time representative signal to provide a comparison signal representative of the relative positions of the signal peaks; m. changing the level of the analyzer field to a different value which also causes the ions of the first mass number to be directed substantially toward the ion collector; and, n. repeating the steps of c) through f) and h) through l) until the value of the comparison signal equals substantially zero.

Claim 42

A method of peak matching with a mass spectrometer comprising the steps of: a. establishing a magnetic field with a magnetic analyzer of the mass spectrometer; b. adjusting the level of the magnetic field such that ions of a first mass number are directed substantially toward an ion collector; c. scanning the magnetic field over a range necessary to cause the waveform of a first output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; d. integrating said output signal during the scanning of the magnetic field to provide a first integral signal; e. integrating said first integral signal during the scanning of the magnetic field to provide a second integral signal; f. dividing said second integral signal by said first integral signal to provide a signal having a value representative of the elapsed time betweEn the time of occurrence of a centroid of said first ion collector output signal and the termination of the scanning; g. adjusting the level of the magnetic field such that ions of a second mass number are directed substantially toward the ion collector; h. scanning the magnetic field over a range necessary to cause the waveform of a second output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; i. integrating said second output signal during the second scanning of the analyzer field to provide a third integral signal; j. integrating said third integral signal during the second scanning of the analyzer field to provide a fourth integral signal; k. dividing said fourth integral signal by said third integral signal to provide another signal having a value representative of the elapsed time between the time of occurrence of a centroid of said second ion collector output signal and the termination of the second scanning; and, l. subtracting the value of one of said elapsed time representative signals from the value of the other elapsed time representative signal to provide a comparison signal representative of the relative positions of the signal peaks.

Claim 43

A method of peak matching with a mass spectrometer comprising the steps of: a. establishing a magnetic field with a magnetic analyzer of the mass spectrometer; b. adjusting the level of the magnetic field such that ions of a first mass number are directed substantially toward an ion collector; c. scanning the magnetic field over a range necessary to cause the waveform of a first output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; d. integrating said output signal during the scanning of the magnetic field to provide a first integral signal; e. integrating said first integral signal during the scanning of the magnetic field to provide a second integral signal; f. dividing said second integral signal by said first integral signal to provide a signal having a value representative of the elapsed time betweEn the time of occurrence of a centroid of said first ion collector output signal and the termination of the scanning; g. adjusting the level of the magnetic field such that ions of a second mass number are directed substantially toward the ion collector; h. scanning the magnetic field over a range necessary to cause the waveform of a second output signal developed by the ion collector resulting from the ions striking the collector to take the form of a signal which increases in value for a given interval of time and decreases in value for a given interval of time to thereby define a peak amplitude; i. integrating said second output signal during the second scanning of the analyzer field to provide a third integral signal; j. integrating said third integral signal during the second scanning of the analyzer field to provide a fourth integral signal; k. dividing said fourth integral signal by said third integral signal to provide another signal having a value representative of the elapsed time between the time of occurrence of a centroid of said second ion collector output signal and the termination of the second scanning; and, l. subtracting the value of one of said elapsed time representative signals from the value of the other elapsed time representative signal to provide a comparison signal representative of the relative positions of the signal peaks.