Since the replication process is a relative newcomer to optical component manufacture, it had to be adopted to existing call-outs of both commercial and military specifications. In the past most marketing activities by replication houses were directed at the technical staff of user companies. The resultant incorporation of replicated elements into the various optical systems tended to be functional and, for the most part, did not conflict with standard specifications. Now that thin film replication has become an accepted mode of fabrication, larger numbers of people with only a cursory understanding of the "replication process" are put into positions where they have to make decisions of its final use. This may conceivably lead to conflicts in specifications since a variety of substrate materials may be involved, requiring very specific heat treating and surface preparations. Unless the document issuing authority is very familiar with these processes, it should refrain from de-tailed work instructions. In most cases it is much more functional to only specify performance and en-vironmental requirements and leave it up to the component manufacturer to select his own process. This paper will attempt to clarify potential areas of conflict.
Harro W. D. Wahl,
"Specification Of Thin Film Replication", Proc. SPIE 0406, Optical Specifications: Components and Systems, (9 December 1983); doi: 10.1117/12.935673; https://doi.org/10.1117/12.935673