Ion Mirror Wedge Field for TOF MS Time-Front Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multi-reflecting time-of-flight mass spectrometers and electrostatic ion traps face challenges in maintaining isochronicity and mass resolving power due to minor ion mirror misalignments, which cause tilting of ion packets' time fronts, leading to reduced performance and accuracy, especially when dealing with wide ion packets.
Innovation Solution
The implementation of an ion mirror with a wedge-shaped electric field region having equipotential field lines that diverge or converge along the Z-direction, allowing for tilting of the ion packet's time front to compensate for misalignments and maintain isochronicity, while minimizing changes to the mean ion trajectory.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional parallel ion mirrors are used, then the structure is simple and manufacturing is easier, but ion packet time front tilting occurs due to misalignments reducing mass resolving power
Solution Approach 1:
The patent changes the geometric parameters of the ion mirror electrodes from parallel to wedge-shaped, creating a controlled electric field gradient that compensates for time front tilting caused by misalignments. This parameter change allows the system to maintain high mass resolving power even with lower precision electrode alignment.
Solution Approach 2:
The patent converts the harmful effect of electrode misalignments (which cause time front tilting) into a beneficial effect by using the same misalignments to create a wedge-shaped electric field that actively compensates for and corrects the time front tilting, thereby maintaining or improving mass resolving power.
2Measurement precision
If wedge-shaped electric field region is implemented, then ion packet time front tilting is compensated improving mass resolving power, but device structure becomes more complex
Solution Approach 1:
The patent applies local quality by creating a wedge-shaped electric field region specifically in the ion reflecting area of the ion mirror, while the rest of the structure remains relatively simple. This localized modification provides the necessary time front compensation without requiring complete structural redesign.
Solution Approach 2:
The patent implements adjustable voltage supplies that allow dynamic control of the wedge-shaped electric field strength and configuration, enabling the system to adapt to different operating conditions and misalignment levels, thereby optimizing mass resolving power across various scenarios.
3Measurement precision
If higher precision electrode alignment is required, then mass resolving power is maintained, but manufacturing cost and difficulty increase
Solution Approach 1:
The patent changes the electric field configuration parameter from uniform (parallel mirrors) to gradient-based (wedge-shaped), which fundamentally alters how the system responds to alignment variations. This parameter change makes the system less sensitive to manufacturing precision requirements while maintaining high mass resolving power.
Solution Approach 2:
The patent converts the previously harmful effect of alignment imprecision into a beneficial feature by designing the wedge-shaped electric field to exploit and compensate for typical alignment variations, thereby reducing the need for high-precision manufacturing while maintaining or improving performance.
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 solution provides a strong amplifying effect on the tilting of ion packet time fronts, improving the mass resolving power and isochronicity of the spectrometers, allowing for higher resolution and reduced ion losses, even with lower precision in electrode alignment.
Implementation Method 1
a plurality of electrodes and at least one voltage supply connected thereto that are configured to generate an electric field region that reflects ions in a first dimension (X-dimension)
Implementation Method 2
at least part of the electric field region through which ions travel in use has equipotential field lines that diverge or converge as a function of position along a second, orthogonal dimension (Z-direction)
Data Source
AI summary
Improved ion mirrors 30 (FIG. 3) are proposed for multi-reflecting TOF MS and electrostatic traps. Minor and controlled variation by means of arranging a localized wedge field structure 35 at the ion retarding region was found to produce major tilt of ion packets time fronts 39. Combining wedge reflecting fields with compensated deflectors is proposed for electrically controlled compensation of local and global misalignments, for improved ion injection and for reversing ion motion in the drift direction. Fine ion optical properties of methods and embodiments are verified in ion optical simulations.