Right Angle TOF Detector with Magnetic Converter

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Time-of-flight mass spectrometers face limitations in detector dynamic range and lifetime due to saturation issues with existing detectors, which restrict their ability to handle high ion fluxes and maintain accurate signal detection over time.

Innovation Solution

A time-of-flight detector design featuring a right-angle magnetic converter, a fast organic scintillator, and a sealed photomultiplier tube (PMT) without an MCP stage, utilizing a deposited metal mesh to enhance electron collection and photon emission, and spatial focusing to minimize time distortions and aberrations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If dual microchannel plate (MCP) detectors are used to achieve sub-nanosecond detection speeds at 1E+6 gain, then detection speed is improved, but the detector saturates at ion fluxes above 1E+6 ion/sec/cm2 and lifetime is limited to approximately 1 Coulomb

Engineering Contradiction:

Improvedetection speedVSAvoiddetector lifetime

Core Design Contradiction:

SpeedVSDuration of action of stationary object

Solution Approach 1:

The patent removes the MCP stage entirely from the detector design, extracting the problematic electron amplification component that limited lifetime. Instead, it uses a magnetic converter coupled directly to a photomultiplier tube, achieving both fast detection and extended lifetime by eliminating the saturation-prone MCP amplification stage.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the mechanical/electronic MCP amplification system with a magnetic field-based electron collection system. The magnetic converter uses magnetic fields to guide and focus electrons onto the photomultiplier tube, substituting the solid-state MCP mechanism with a field-based approach that avoids saturation and extends operational lifetime.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If MCP electron amplification is used to detect individual ions, then detection sensitivity is improved, but the scintillator degrades faster by depleting the thin metal coating and destroying the scintillator surface

Engineering Contradiction:

Improvedetection sensitivityVSAvoidscintillator lifetime

Core Design Contradiction:

Measurement precisionVSDuration of action of stationary object

Solution Approach 1:

The patent extracts and removes the MCP amplification stage that causes scintillator degradation. By eliminating the high-gain MCP electron multiplication process, the intense electron bombardment that depletes metal coatings and destroys scintillator surfaces is avoided, thereby extending scintillator lifetime while maintaining detection capability through the magnetic converter-photomultiplier system.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces a magnetic converter as an intermediary between the ion beam and the photomultiplier tube. This intermediary uses magnetic fields to convert ion impacts into electron signals without requiring the destructive high-gain MCP amplification process, protecting the scintillator from degradation while maintaining detection sensitivity.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Volume of moving object

If a right-angled detector configuration is used to save space in multi-reflecting TOF mass spectrometers, then device compactness is improved, but time distortions and aberrations increase

Engineering Contradiction:

Improvedetector volumeVSAvoidtime measurement accuracy

Core Design Contradiction:

Volume of moving objectVSMeasurement precision

Solution Approach 1:

The patent employs curved or spherical magnetic field geometries in the magnetic converter to focus electrons and compensate for the time distortions introduced by the right-angled configuration. The curved magnetic field lines help equalize electron flight paths and reduce aberrations, maintaining time measurement accuracy despite the compact right-angled arrangement.

Inventive Principle:

Principle #14Spheroidality (Curvature)

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 significantly extends the detector's dynamic range and lifetime, enabling efficient detection of individual ions with improved immunity to noise and convenient mounting, while minimizing the appearance of slow fluorescence signals.

Implementation Method 1

at least one magnet bends electron trajectories towards the side window with a magnetic field strength in an electron propagation region between 10 and 1000 Gauss

Methodology Applied

Scientific EffectMagnetic field: Magnetic Field

Implementation Method 2

High energy electrons emit photons from the scintillator

Methodology Applied

Scientific EffectScintillation: Scintillation

Implementation Method 3

Photons are detected by a PMT

Methodology Applied

Scientific EffectPhotoelectric effect: Photoelectric Effect

Data Source

PatentUS10770280B2Right angle time-of-flight detector with an extended life time

Publication Date: 2020.09.08 LECO CORP

AI summary

There is proposed a right angle time-of-flight detector comprising a conductive converter for emitting and accelerating secondary electrons, a magnetic field formed by at least one magnet for deflecting the secondary electrons at a right angle and a sealed photo-multiplier. The detector is expected to provide an extended resource and dynamic range and may be fit into tight assemblies, such as MR-TOF MS.