Optical lenses use materials like glass to converge light through refraction. On the other hand, electron lenses converge electron beams or ion beams using the effects of electromagnetic fields.
Electron lenses are classified into types such as electrostatic lenses and electromagnetic lenses. While optical lenses include both concave and convex lenses, electric and magnetic field lenses can only function as convex lenses. The basic structure of an electrostatic lens consists of a central electrode with a negative charge, flanked by upper and lower external electrodes with a positive charge. This configuration creates an equipotential surface that bulges out in the shape of a lens.
Since electrons move under uniform acceleration within an electric field in a direction perpendicular to the equipotential surface, their trajectory can be altered according to the shape of that surface.
Electron lenses are used in instruments like Scanning Electron Microscopes (SEMs) for analyzing samples. In a scanning electron microscope, an electron beam emitted from an electron gun in the microscope column is converged by an electron lens to scan the surface of the sample. Furthermore, the electron beam emitted from the sample is captured by a detector and output as an image.
Matsusada Precision offers high-voltage power supplies that can be used for electrostatic lens electrodes, constant-current power supplies suitable for magnetic field lenses, and high-voltage amplifiers capable of bipolar (positive and negative) output.
- Related Terms:
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- Electron Gun
- Electron Beam
- Ion Beam
- Electrode
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Matsusada Precision offers high-voltage power supplies that can be used for electrostatic lens electrodes, constant-current power supplies suitable for magnetic field lenses, and high-voltage amplifiers capable of bipolar (positive and negative) output.
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