Capacitance Adjustment Unit for Time-of-Flight Mass Spectrometer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Stray capacitance between electrodes in time-of-flight mass spectrometry devices causes voltage fluctuations, affecting measurement accuracy by altering flight times, which existing methods cannot completely eliminate.
Innovation Solution
An analytical device with a capacitance adjustment unit that adjusts capacitance between electrodes in the acceleration units and flight tube, using capacitors to stabilize voltages and reduce voltage fluctuations, thereby minimizing flight time shifts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If stray capacitance is reduced by directly connecting grounded capacitor and each electrode, then voltage fluctuation is reduced, but voltage fluctuation cannot be completely eliminated
Solution Approach 1:
The patent introduces a capacitance adjustment unit as an intermediary component between the pulse voltage application system and the electrodes. This unit actively compensates for stray capacitance effects by adjusting the capacitance between specific electrodes (such as between the first acceleration electrode and second acceleration electrode, or between first acceleration electrode and flight tube electrode). The capacitance adjustment unit acts as a mediator that counterbalances the unwanted stray capacitance, thereby stabilizing voltages more effectively than direct grounded capacitor connections alone.
Solution Approach 2:
The patent dynamically adjusts capacitance parameters between electrodes to compensate for stray capacitance effects. By changing the capacitance value (through variable capacitors or adjustable capacitor configurations) in response to detected voltage fluctuations or measurement conditions, the system optimizes voltage stability. This parameter adjustment allows the system to adapt to varying stray capacitance conditions and maintain precise flight time measurements.
2Speed
If pulse voltage is applied to accelerate ions, then ion acceleration is achieved, but voltage fluctuations occur due to stray capacitance between electrodes
Solution Approach 1:
The patent divides the acceleration system into multiple segmented components: first acceleration electrode, second acceleration electrode, and flight tube electrode, each with controlled capacitance relationships. The capacitance adjustment unit specifically manages capacitance between these segmented electrodes (e.g., between first and second acceleration electrodes, or between first acceleration electrode and flight tube electrode). This segmentation allows independent control and optimization of voltage stability for each electrode while maintaining ion acceleration functionality.
Solution Approach 2:
The capacitance adjustment unit serves as an intermediary that mediates between the pulse voltage application and the electrode system. It introduces controlled capacitance elements that counterbalance the stray capacitance between acceleration electrodes and the flight tube electrode, thereby stabilizing voltages during ion acceleration without compromising acceleration efficiency.
3Measurement precision
If capacitance between electrodes is adjusted, then voltage fluctuations are reduced, but device complexity increases
Solution Approach 1:
The capacitance adjustment unit is designed as a dedicated intermediary component that simplifies the overall system architecture by centralizing the capacitance management function. Rather than requiring complex distributed control across multiple electrodes, the capacitance adjustment unit consolidates the capacitance adjustment mechanism in one location, managing capacitance between key electrode pairs (first acceleration electrode and second acceleration electrode, or first acceleration electrode and flight tube electrode) through a unified control approach.
Solution Approach 2:
The system employs adjustable capacitance parameters that can be optimized for different measurement conditions. The capacitance adjustment unit allows dynamic modification of capacitance values to match specific experimental requirements, enabling the system to maintain high measurement precision across varying conditions without requiring a completely different configuration for each scenario.
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
The solution precisely adjusts capacitance to reduce voltage fluctuations, enhancing measurement accuracy and allowing for efficient detection of ions with various m/z ratios by stabilizing flight times.
Implementation Method 1
Stray capacitance is generated between a plurality of electrodes to which a pulse voltage or a constant voltage is applied to accelerate ions. Due to this stray capacitance, there is a problem that the pulse voltage applied to the electrodes causes voltage fluctuations of other electrodes
Implementation Method 2
ions are accelerated by an electric field generated by a pulse voltage and a constant voltage
Implementation Method 3
m/z (mass-to-charge ratio) of each ion is measured based on flight time that elapses before accelerated ions are detected by a detector
Data Source
AI summary
An analytical device includes: a first acceleration unit including a first acceleration electrode to which a pulse voltage for accelerating ions is applied; a flight tube; a second acceleration unit that is arranged between the first acceleration unit and the flight tube, and includes a second acceleration electrode to which a voltage for accelerating the ions is applied; an ion detector that detects the ions; and a capacitance adjustment unit that causes adjustment of a capacitance between at least one set of electrodes among a plurality of electrodes arranged in the first acceleration unit, the second acceleration unit, and a flight tube.