Abstract

There are are variety of things which the designer can do to help the fabricator of his designs if he is familiar with the fabrication processes available. We will give some examples. The designer can let the shop know that the overall thickness of a cemented doublet may be critical to performance, but the thickness of the individual components could be off the nominal by quite a bit and still perform if selected in pairs to meet the overall thickness. Lenses with nearly the same curvature on both sides may end up assembled backwards. Sometimes the designer can adjust the design to make the element fully symmetric to avoid the problem. Often whole lens assemblies can be designed to be symmetric such as the classical Double Gauss objective. This cuts in half the types of components to be tooled and fabricated. The designer can often add some thickness to a lens to reduce its flexibility so that the surface figure can be better maintained during fabrication. When cemented doublets must have tight wedge requirements, the designer can allow the components a relaxed tolerance if one lens is intentionally smaller in diameter than the other. This allows the smaller lens to be moved until it compensates the errors of the wedge in the larger lens.

© 1990 Optical Society of America