CO2 laser fusion splicing is a technique for joining optical components, offering precise, non-contact material processing. Due to the high absorption of glasses at 10.6 mu m wavelength, this approach enables controlled localized heating and is well suited for materials that are difficult to process using conventional splicing methods, such as arc or filaments. As photonic circuits, integrated optics, and nonlinear optical materials continue to advance, the demand for splicing dissimilar materials has increased substantially. Such materials often exhibit mismatched physical properties such as thermal expansion coefficients, melting temperatures, and optical properties, requiring specific procedural changes that depend on the materials, fibers and component sizes.