Filament Lifetime Estimation via Low-Voltage Current Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Charged particle beam devices face challenges in estimating the lifetime of filaments due to complex and costly circuit configurations required for measuring high-voltage currents, and existing methods are inefficient for beginners.
Innovation Solution
A boosting circuit is used to supply voltage to the filament, allowing for the estimation of remaining filament life by measuring current on the low-voltage side, simplifying the circuit configuration and enabling accurate lifetime prediction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If floating measurement is used to measure filament current at high voltage, then lifetime estimation becomes possible, but circuit configuration becomes complicated and cost increases
Solution Approach 1:
The patent introduces a current transformer as an intermediary device to measure filament current. The current transformer couples the high-voltage filament circuit to the low-voltage measurement circuit, enabling current measurement without direct electrical connection. This mediator allows accurate current measurement for lifetime estimation while keeping the measurement circuit simple and isolated from high voltage.
2Measurement precision
If high voltage is applied to AD converter for voltage measurement, then measurement is possible, but resolution becomes insufficient
Solution Approach 1:
The patent transforms the voltage measurement problem into a current measurement problem by measuring current on the low-voltage side of the boosting circuit. Instead of directly measuring high voltage with insufficient resolution, the system measures current at low voltage where AD converters have adequate resolution, then calculates voltage from the current measurement and circuit parameters.
3Use of energy by moving object
If filament is used at high temperature for thermoelectron generation, then electron emission is achieved, but filament wear increases and lifetime decreases
Solution Approach 1:
The patent implements a feedback mechanism that continuously monitors filament current and calculates remaining lifetime based on current consumption patterns. The system provides real-time feedback about filament degradation to the user, enabling proactive replacement before catastrophic failure. This feedback loop allows optimization of filament usage and extends effective operational life through predictive maintenance.
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 approach allows for accurate estimation of filament lifetime with a cheap and simple circuit, reducing the risk of filament disconnection during observation and improving device efficiency.
Implementation Method 1
a boosting circuit which boosts a voltage to be supplied to a filament
Implementation Method 2
a voltage is applied to both ends of the filament and a thermoelectron generated at the time of heating of the filament is used
Implementation Method 3
a thermoelectron generated at the time of heating of the filament is used
Data Source
AI summary
An objective of the present invention is to provide a charged particle beam device capable of estimating a lifetime of a filament of a charged particle beam source with a cheap and simple circuit configuration. The charged particle beam device according to the present invention includes a boosting circuit that boosts a voltage to be supplied to a filament and estimates a remaining duration of the filament using a measured value of a current flowing on a low-voltage side of the boosting circuit (see FIG. 3).