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of the glass melting process. Unlike the foams formed on the free surface of the molten glass that possess a structure of multiple layers of spherical or polyhedral bubbles separated by the liquid lamella, the batch foam is a collection of often non-overlapping individual gas bubbles that only partially emerge from the batch Fig. 1~a!. Hence, a thin hemispherical shell placed on top of the opaque surface as shown in Fig. 1~b! can be considered as a fairly good simplified representation of the batch foam. Due to signifi-cant structural differences, the radiative transfer models developed for conventional glass foams @2,3 # cannot be used for the batch foams, and thus prediction of the apparent radiative characteristics of batch foams is the subject of this paper. In addition to glass manufacturing, understanding of the local radiant heating of a semitransparent hemispherical shell is needed for optimization of the novel process for fabrication of hollow perforated beads for acoustic and thermal insulation @4#. In this process, the gas is injected from a small orifice into the molten droplet placed on the substrate to form a bubble surrounded by the thin lamella of the liquid material, which is then solidified by rapid cooling through the substrate to form a solid hemispherical bead. The parameters ~e.g., the shell thickness and structure! and ing. These properties are critically important to optical, spectroscopic studies of the foam morphology ~i.e., phase func-tion! and mechanisms of the foam rapture due to the local ther-mally induced instabilities and stress ~i.e., volumetric heating rate!. To further elucidate the results, the comparison is made of the total apparent transmittance of the hemispherical shell to that for a plane parallel layer of the same semitransparent materia