Multi-Reflection Mass Spectrometer Mirror Configuration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multi-reflection mass spectrometers face limitations in extending ion flight path length due to beam divergence and space charge effects, which restricts the number of reflections and mass resolution, particularly in designs with constant mirror distances and complex alignment requirements.
Innovation Solution
The use of non-parallel ion-optical mirrors with varying distances and inclinations along the drift direction, combined with compensation electrodes, allows for a longer flight path and improved focusing, enabling adjustable reflection cycles and reduced space charge interactions without additional lenses or diaphragms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If parallel opposing mirrors with constant distance are used, then the construction is simple, but beam divergence increases and mass resolution is limited
Solution Approach 1:
The patent applies asymmetry by using non-parallel mirrors with varying distances between them along the drift direction. The first mirror has a first distance to the second mirror at a first position, and a second distance at a second position, creating an asymmetric configuration that focuses ion beams and reduces divergence while maintaining construction feasibility
Solution Approach 2:
The patent implements dynamics by making the mirror configuration adjustable. The distance between mirrors can be varied along the drift direction, and the system can accommodate different injection angles to change the number of reflections. This dynamic adjustment allows optimization of both beam focusing and mass resolution without requiring complete redesign
2Measurement precision
If the number of reflections is increased to extend flight path, then mass resolution improves, but beam divergence causes ion loss and sensitivity decreases
Solution Approach 1:
The patent applies local quality by creating different spatial zones within the mirror system. The varying mirror distances create regions with different focusing properties along the drift direction, allowing ions to be focused at specific locations while maintaining extended flight paths. This local variation in mirror configuration prevents beam divergence-induced ion loss
Solution Approach 2:
The patent implements feedback through the geometric configuration of the non-parallel mirrors. The varying distances between mirrors create a self-focusing effect where ions that diverge are naturally refocused by the changing mirror geometry, providing automatic correction without additional control mechanisms
3Length of stationary object
If multiple lenses and diaphragms are added to control beam divergence, then flight path can be extended, but device complexity increases
Solution Approach 1:
The patent extracts the beam focusing function from separate optical components (lenses and diaphragms) and integrates it directly into the mirror configuration itself. The non-parallel mirror arrangement inherently provides focusing capability, eliminating the need for additional focusing lenses and reducing device complexity
Solution Approach 2:
The patent applies multi-functionality by making the mirrors serve multiple purposes: they both reflect ions to extend the flight path and simultaneously focus the ion beams through their non-parallel configuration. This eliminates the need for separate focusing components and reduces the overall number of parts in the system
4Measurement precision
If mirrors are inclined to control beam divergence, then focusing improves, but alignment precision requirements increase
Solution Approach 1:
The patent applies segmentation by dividing the mirror system into discrete sections with specific inclination angles. The first and second mirrors can be independently positioned and angled, allowing for modular assembly and adjustment. This segmentation makes the alignment process more manageable and reduces the cumulative error that would occur in a continuously varying configuration
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 configuration enhances mass resolution and extends the flight path length while maintaining simplicity in construction and reducing time-of-flight aberrations, allowing for more precise ion detection and analysis.
Implementation Method 1
ions follow a zigzag flight path, reflecting between the mirrors
Implementation Method 2
the mirrors are not a constant distance from each other in the X direction along at least a portion of their lengths in the drift direction
Implementation Method 3
combined with compensation electrodes, allows for a longer flight path and improved focusing, enabling adjustable reflection cycles and reduced space charge interactions
Implementation Method 4
high mass resolution time-of-flight mass spectrometry
Data Source
AI summary
A multi-reflection mass spectrometer comprising two ion-optical mirrors, each mirror elongated generally along a drift direction (Y), each mirror opposing the other in an X direction and having a space therebetween, the X direction being orthogonal to Y; the mass spectrometer further comprising one or more compensation electrodes each electrode being located in or adjacent the space extending between the opposing mirrors; the compensation electrodes being configured and electrically biased in use so as to produce, in at least a portion of the space extending between the mirrors, an electrical potential offset which: (i) varies as a function of the distance along the drift length, and/or; (ii) has a different extent in the X direction as a function of the distance along the drift length. In a preferred embodiment the period of ion oscillation between the mirrors is not substantially constant along the whole of the drift length.