The design of magnetic field gradients and the calculation of electromagnetic equipment is decisive for the effectiveness of the magnetic lens flip over. The electromagnets need special design features for a proper operation of the Magnetic Auto Flip Over system. They can be prepared for installation inside or outside of the vacuum chamber. The special configuration of the magnets concentrates and directs the magnetic field to where it is needed.
The design of the lens holder allows a rotation around its rotational axis and at the same time ensures a stable bedding during the deposition process. The partly magnetizable holder can easily be mounted into the bearing supports on the dome segment. Its material suits vacuum coating demands as well as cleaning standards.
Q: Do lenses fall out of the spring holder during the turn-over step?
A: Spring rings are well established as holders of plastic lenses for vacuum coating. The risk for lenses to fall out of the Auto Flip Over lens holders is not greater than for regular spring rings.
Q: Does the magnetic field effect the coating process?
A: No. The electromagnets are only switched on for the turn-over step between two coating runs. The remanence of the magnetizable parts is limited by the type of material that is chosen. For common materials it is much to small to effect the operation of an electron gun or the impact of ion treatment.