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Calculates the axial and the height chromatisms of a thin lens as functions of the constringence, the focal length, the object height and the object position. The chromatism is calculated in a spectral range between 486.13 nm (blue hydrogen line) and 656.27 nm (red hydrogen line).
Also, the focal length fi is considered at 587.56 nm (yellow helium line). Therefore, the parameters xi and yi are calculated at this wavelength.