Precision Optics Manufacturing of Large Hemispherical Domes

There are currently three different approaches under consideration for construction of multi-layer hemispherical multi-mode domes: (1) The bonded shell method – in which an inner and an outer dome shell are fabricated out of either ALON or Spinel, and bonded together, using a transparent adhesive, with a metallic grid at the interface, (2) The alternate dielectric method- in which an outer shell is fabricated out of either ALON or spinel, a grid is applied to its inner surface, and then an alternate dielectric (i.e., glass) material is directly bonded to the outer shell to create the desired structure, and (3) The Co-fired ceramic method- in which the metal grid is applied to green ceramics, and fired in such a way as to create the multi-layer structure within the as fired blank. The Phase I effort will combine a trade study of the preferred assembly method with a study of deterministic finishing techniques to determine the optimized manufacturing path toward producing a 7-in hemispherical dome with ¼ wave transmitted wavefront uniformity over any 4-in aperture. The Phase II effort will then consist of optimizing the selected method with a feasibility demonstration for producing up to 250 domes per month.