Advancing the Manufacturing of High Precision Optics by Replication in Different Substrate Materials

Three new replication techniques will be developed to reduce the costs of manufacturing precision diffractive gratings and optics, binary optics, microoptics and computer generated holograms. These replication techniques will show their advantages especially when they are non-central symmetric (e.g. aspherics), their aperture areas are not circular (e.g. square or hexagonal), and/or they are in an array format with precise center-to-center spacings. The first technique can be applied to replicate infrared as well as visible precision optics on environmentally durable substrates. It requires first generating a gray level mask with only one writing step by controlling the electron dosage spatially . Then, using this gray level mask, it requires for each copy only one iteration of exposing the analog photoresist and transferring the analog photoresist pattern into the substrate by chemically assisted ion beam etching (CAIBE). Since multiple substrates can be etched simultaneously, the CAIBE is a batch process and the etching cost for each copy is reduced. Moreover, since the same gray level mask can be used over and over again for making many copies, the cost of generating the gray level mask will be spread over the number of copies. The second replication technique starts with using the first technique just described to produce a master on a special metal/alloy material to be specified by Honeywell/Donnelly Optics. Given the new master they will then produce many precision replicas of plastic optics by injection molding. The third replication technique starts with a master on glass, replicas are made from liquid photopolymer by molding. Both the second and third replication techniques are applicable only to visible precision optics. Our technical objectives for Phase I will be evaluation of the feasibility of these replication techniques. The overall effort will be divided as follows: 60% to the first replication techinique, 15% to the second and 25% to the third. Anticipated Military Benefits/Potential Commercial Applications of the Research or Developments: By developing new replication techniques the cost of manufacturing small precision optics will be lowered, thus eliminating the majo