Abstract: In accordance with the invention a planar waveguide device is fabricated by providing a substrate with an undercladding, depositing a particulate layer of core glass on the undercladding, consolidating the particulate layer by low temperature viscous sintering, patterning the consolidated layer to form an optical waveguide and applying an overcladding. The glass layers can be deposited quickly and economically by slurry dipping, centrifuging or electrophoresis. In a preferred embodiment the substrate is silicon, and the core glass is sodium-boro-silicate.

Abstract: Incidence of breakage in optical fiber drawn from sol-gel produced preforms is reduced by treatment of the still-porous glass by use of a chlorine-containing, oxygen-free gas mixture. Improved satisfaction of proof-rest requirements to at least 100 kpsi is assured by size reduction of unassimilated discrete particles in the fiber.

Abstract: Optical fiber drawn from preforms including sol-gel-derived glass is found to contain small refractory particles of the order of a micron in size. These particles initiate fiber breaks with the result that fiber may not meet proof-test tensile strength requirements. An effective separation method relies upon density and/or size difference from suspended sol particles for separation in the ungelled sol. A preferred separation procedure is centrifugation.