Mass Spectrometer Sampling Error Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Time-of-flight mass spectrometers face limitations in statistical accuracy and noise due to sampling errors introduced by analog-to-digital converters, which affect the precision and reliability of mass spectra obtained.
Innovation Solution
A mass spectrometer system employing multiple analog-to-digital converters that sample ion detector signals in parallel, with a controller compensating for sampling errors by ensuring corresponding samples from different scans are properly summed, thereby reducing offset and gain errors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple A/D converters are used to sample ion detector signals in parallel, then the sampling rate and productivity are improved, but sampling errors such as offset and gain errors are introduced
Solution Approach 1:
The patent divides the sampling task into multiple parallel A/D converters, each handling a portion of the ion detector signals. This segmentation enables higher overall sampling rates while managing the complexity of error compensation through systematic calibration of each individual converter
Solution Approach 2:
The patent applies parameter changes by introducing calibration factors for offset and gain that modify the output parameters of each A/D converter. These calibration parameters are determined through calibration procedures and applied to compensate for systematic errors, transforming the raw converter outputs into accurate measurements
2Measurement precision
If multiple mass scans are summed to achieve desired statistical accuracy, then the signal-to-noise ratio is improved, but the time required and loss of time increase
Solution Approach 1:
The patent implements continuous useful action by performing multiple mass scans and summing their results. This accumulation of data from consecutive scans continuously improves the signal-to-noise ratio and statistical accuracy, maintaining productive operation throughout the measurement process
3Reliability
If the mass scan is repeated multiple times to improve statistical accuracy, then the reliability is improved, but the productivity decreases
Solution Approach 1:
The patent segments the measurement process into multiple parallel scanning channels using multiple A/D converters. This allows simultaneous acquisition of multiple spectra that can be summed, improving reliability through data accumulation while maintaining higher overall productivity through parallel operation
Solution Approach 2:
The patent performs preliminary calibration of the A/D converters for offset and gain errors before actual measurements. This preliminary action ensures that subsequent repeated scans produce accurate results that can be reliably summed, improving both reliability and productivity by eliminating the need for extensive post-processing corrections
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances the statistical accuracy and signal-to-noise ratio of mass spectra by canceling out errors between converters, leading to a more reliable and precise mass spectrometry outcome.
Implementation Method 1
An ion detector converts ion impacts into electrons
Implementation Method 2
A/D converters configured to sample an analog signal from the ion detector at different times, the A/D converters introducing sampling errors
Implementation Method 3
the controller being programmed to compensate for the sampling errors by adjusting the timing of mass scans
Data Source
AI summary
A mass spectrometer system includes an ion detector, a plurality of analog-to-digital (A/D) converters, an adder, and a controller. The A/D converters are configured to sample an analog signal from the ion detector at different times, and the A/D converters introduce sampling errors to digital samples generated by the A/D converters. The adder is configured to sum the digital samples, and the summed digital samples define a mass spectrum. The controller is configured to compensate for the sampling errors introduced by the A/D converters.