Lens Design and Testing

Abstract

Different types of superconducting rotationally symmetric lenses for which field distributions have been obtained are described in the literature. The axial field measurements were usually carried out with low-temperature Hall probes, magnetoresistance probes, or probe coils. In one case the field distribution in the whole lens was determined from a model in an electrolytic tank (Dietrich and Weyl, 1968). Yet the normal procedure for obtaining the field distribution is to calculate it with a computer program. For simple coils, the Biot-Savart method is appropriate. In the case of more complex boundary conditions, the Laplace equation has to be solved.