Impact of optical inhomogeneity in sintered interface between glasses on laser emission characteristics

This paper details an experimental study of the influence of the optical inhomogeneities produced during the sintering process in the interface on the spatial and energy parameters of neodymium laser emissions when the sintered boundary is located inside the cavity perpendicular to its optical axis. Three samples of phosphate glass 10x20x30 mm were prepared by sintering together two pieces at a viscosity of 10 to the 9th power -10 to the 8th power. Following the polishing of the outer surfaces of the samples, the deformation of the sintered surfaces were determined using a Mach-Zehnder interferometer. Photographs of the interference patterns from the interfaces clearly show various maximum deviations from the desired surface of between 0.32 mm and 1.6 mm, due to optical inhomogeneities. Two kinds of optical inhomogeneities can be produced in the interface during sintering: small-scale ones, related to the presence of dust particles, inclusions, etc., and large scale inhomogeneities, related to the plastic deformation of the glass being joined.