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Planar polymer waveguides provide opportunities for small form factor distribution of laser light
for communication, energy transfer and triggering devices used in the field of optically initiated
arming, safing, fusing and firing. The two primary methods or classes of polymer waveguide
technology use photolithographic processes both mask and maskless techniques. A waveguide is
a device that controls the propagation of an electromagnetic wave so that the wave is forced to
follow a path defined by the physical structure of the guide. Fabrication takes the form of both a
ridge technology (ridge or trench formed by an embossing or etching method) and the second
fabrication technique and the subject of this paper is termed Diffusion Technology [1]. This
method includes the formation of a high refractive index waveguide by monomer diffusion into
the light-exposed guide forming region with no mechanical or chemical etching contact. An
essential process feature here is the photomask-defined light exposure of a mobile monomer
waveguide forming region in a polymer matrix that converts the monomer to a polymer. The
process of continued monomer diffusion into the surrounding guide imaged region increases the
density. The addition of other laminated monomer/polymer diffusing layers with the typical
three-plus layer configuration is completely photopolymerized after diffusion is complete. The
essential steps include a light induced imaging reaction, a total polymerization light fixing for the
entire film, and final cure, all using pre-coated dry materials without waveguide side wall
contact. Light and molecular diffusion determine the guide walls [1]. This paper will provide
testing results and information on the state of polymer waveguides, the methods of fabrication
and the general conditions that these waveguides can operate under. The use of polymer
waveguides for connectivity has sufficiently advanced, is practical and available for
consideration in near term application development with the field of arming, safing, fusing and
firing or laser/optically initiated ordnance.
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