Abstract: This invention resides in an apparatus and related method for rapidly curing thin film sol-gel coatings, particularly such coatings adhered to low melting temperature plastic substrates, whether rigid or flexible, without deforming the substrate. The curing is achieved using IR heating lamps and dry or humid hot gas flow. This curing densities the sol-gel coating and provides desired optical and mechanical properties. The use of IR lamps and hot-gas nozzles, either singularly or in combination, produces a rapid cure by effectively heating the thin film coating layer. In this manner, a sufficiently high temperature can be attained in the film layer, to densify the sol-gel coating, but for a sufficiently short time duration to avoid melting or otherwise deforming the substrate. The sol-gel coatings can be cured two to three orders of magnitude faster than with conventional oven curing, leading to significant cost reductions and manufacturing efficiency.

Abstract: This invention resides in an apparatus and related method for rapidly curing thin film sol-gel coatings, particularly such coatings adhered to low melting temperature plastic substrates, whether rigid or flexible, without deforming the substrate. The curing is achieved using IR heating lamps and dry or humid hot gas flow. This curing densities the sol-gel coating and provides desired optical and mechanical properties. The use of IR lamps and hot-gas nozzles, either singularly or in combination, produces a rapid cure by effectively heating the thin film coating layer. In this manner, a sufficiently high temperature can be attained in the film layer, to densify the sol-gel coating, but for a sufficiently short time duration to avoid melting or otherwise deforming the substrate. The sol-gel coatings can be cured two to three orders of magnitude faster than with conventional oven curing, leading to significant cost reductions and manufacturing efficiency.

Abstract: Low attenuation, low dispersion of optical waveguides are provided by a process initiating with axial deposition of a high velocity core soot stream impinging on a target at a high angle of incidence relative to the axis of rotation of the target. A core cylinder is built up axially by relative movement between the soot stream and target during deposition, the movement being non-constant in order to maintain a substantially constant diameter with a constant deposition rate. A cladding layer is then built up by deposition of soot radially on the core. Subsequent drying and sintering provides a vitreous preform which may be drawn directly into optical waveguides. Alternatively, the sintered product may be drawn down to smaller rods, which then are covered with further deposited soot cladding to a desired final thickness, and after further drying and sintering may be drawn to optical waveguides.