Drift Tube Voltage Driving Subsystem for Ion Mobility Detectors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Uncertainty in the timing of high voltage signals in ion mobility detectors affects the accuracy of ion time of flight measurements and subsequent ion composition determination.
Innovation Solution
The implementation of a drift tube voltage driving subsystem that includes a high voltage base module, a high voltage deck module, and an interconnect module, which generates and regulates high voltage signals with controlled rise and fall times, and uses photodiodes and PID controllers to ensure accurate and repeatable voltage transitions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high voltage is applied to the drift tube grid to generate a uniform electric field, then ion mobility detection is enabled, but timing uncertainty in voltage transitions affects measurement precision
Solution Approach 1:
The patent replaces traditional electronic voltage switching mechanisms with a photodiode-based optical control system. The voltage transitions are controlled by light pulses from LEDs that activate photodiodes, which then trigger the high voltage switches. This optical-mechanical substitution eliminates electrical interference and timing jitter associated with conventional electronic switching, providing more precise and repeatable voltage transitions for accurate time of flight measurements
Solution Approach 2:
The patent implements a feedback mechanism where the timing and intensity of LED light pulses are precisely controlled based on desired voltage transition requirements. The system monitors and adjusts the optical signals to ensure consistent voltage application timing, thereby improving the reliability of voltage transitions and consequently the precision of ion mobility measurements
2Adaptability or versatility
If voltage polarity is periodically reversed to accommodate both positive and negative ions, then detector versatility is improved, but voltage transition timing control becomes more complex
Solution Approach 1:
The patent employs a universal photodiode control mechanism that can drive high voltage transitions in both positive and negative polarities using the same optical control architecture. The LED-photodiode system serves multiple functions: it controls voltage polarity reversal, maintains timing precision, and adapts to different ion types without requiring separate control circuits. This multi-functionality simplifies the overall control system while maintaining versatility for detecting both positive and negative ions
Solution Approach 2:
The patent implements periodic reversal of voltage polarity through synchronized light pulse sequences that trigger photodiodes at regular intervals. This periodic optical signaling creates the necessary bipolar voltage transitions for accommodating different ion types. The regular timing of light pulses ensures consistent voltage switching behavior, making the complex polarity reversal process more manageable and predictable
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 achieves precise control over the drift tube voltage, reducing uncertainty in ion time of flight measurements and enhancing the accuracy of ion composition analysis.
Implementation Method 1
An embodiment may be directed to the use of a photodiode to apply the voltage to the drift tube grid 104
Data Source
AI summary
An apparatus for generating high voltage (HV) driving signals associated with an ion mobility detector comprises a ground-based HV base module and a HV deck module coupled by an interconnect module. The HV base module implements dual power supplies that together drive a drift tube voltage signal to the high-voltage-based deck module. Each of the power supplies is regulated by a combination open loop and closed loop controller. The HV deck module implements one or more grid modules that generate a bipolar voltage that floats on the drift tube voltage signal. Also included may be a pulse generator configured to generate at least one synchronizing timing pulse. Power supplies within the apparatus may be synchronized based on the synchronization timing pulse.