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Edge shadow projection method for measuring the brightness of electron guns
Cheolsu Han1, Inho Sul2, Boklae Cho2
1Korea Basic Science Institute, Daejeon 34133, South Korea.
The Review of Scientific Instruments
|March 3, 2017
Summary
Researchers developed a new system to measure electron gun brightness without electron lenses. This system accurately determines angular current density and virtual source size for improved electron gun performance evaluation.
Area of Science:
- Physics
- Electron Optics
- Instrumentation
Background:
- Electron gun performance is critical for various applications.
- Accurate measurement of electron gun brightness is essential for optimizing performance.
- Existing methods may involve complex setups or approximations.
Purpose of the Study:
- To develop and validate a simplified system for measuring electron gun brightness.
- To accurately determine angular current density and virtual source area.
- To compare measured brightness values with established data.
Main Methods:
- Constructed a measurement system comprising movable apertures, a Faraday cup, and a phosphor screen.
- Utilized a Faraday cup to measure angular current density.
- Employed aperture shade displacement and edge blurring analysis (with a CCD camera) to determine virtual source position and size.
Main Results:
- Successfully measured the brightness of a tungsten filament electron gun.
- Obtained brightness values that were compared to previously reported data.
- Demonstrated the system's capability to evaluate electron gun performance.
Conclusions:
- The developed system provides a viable method for electron gun brightness measurement without electron lenses.
- The system allows for accurate determination of key parameters influencing electron gun performance.
- This approach can aid in the optimization and characterization of electron guns.
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