AI Article Synopsis
- Standard 3D interpolation polynomials often result in numerical errors and lack sufficient node points for 3D solutions, prompting the introduction of a more reliable method for interpolating electromagnetic fields.
- This new method integrates Fourier analysis and Gaussian wavelet interpolation, offering precise and smooth results for multipole field functions and their derivatives, typically accurate up to the 5th derivative.
- The method enhances applications like particle tracing and assessing optical properties, and it is demonstrated through examples involving various magnetic and electrostatic lens configurations.
Article Abstract
Standard 3D interpolation polynomials often suffer from numerical errors of the calculated field and lack of node points in the 3D solution. We introduce a novel method for accurate and smooth interpolation of arbitrary electromagnetic fields in the vicinity of the optical axis valid up to 90% of the bore radius. Our method combines Fourier analysis and Gaussian wavelet interpolation and provides the axial multipole field functions and their derivatives analytically. The results are accurate and noiseless, usually up to the 5th derivative. This is very advantageous for further applications, such as accurate particle tracing, and evaluation of aberration coefficients and other optical properties. The proposed method also enables studying the strength and orientation of all multipole field components. To illustrate the capabilities of the proposed algorithm, we present three examples: a magnetic lens with a hole in the polepiece, a saturated magnetic lens with an elliptic polepiece, and an electrostatic 8-electrode multipole.
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| http://dx.doi.org/10.1016/j.ultramic.2018.03.023 | DOI Listing |
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