Patent ID: 8033142

Claim:
A method for fabricating a Photonic Crystal Fiber preform, comprising the steps of: inserting at least one holding matrix into an overcladding tube having an inner surface, the holding matrix having a solid structure and comprising a plurality of openings spaced apart from one another; inserting a plurality of elongated structural elements into the spaced apart openings in the holding matrix that has been inserted into the overcladding tube, each elongated structural element having an outer surface and being arranged in at least substantially two-dimensionally periodic structure, the outer surfaces and inner surface defining an interior space limited at a first end of the overcladding tube by a closure; holding the structural elements longitudinally substantially-parallel to the overcladding tube, utilizing the holding matrix; supplying overcladding grain into the interior space, the holding matrix being made from the same material as the overcladding grain; limiting the interior space at a second end of the overcladding tube by an adjoiner, wherein the plurality of structural elements, the overcladding tube, the closure, the overcladding grain, and the adjoiner form an unprocessed preform; generating a reduced pressure within the interior space; and heating at least the bottom portion of the unprocessed preform at sufficiently high temperature to melt the grain for obtaining a processed preform.