US Patent 7377130 Method for making globular bodies

The method of making globular or spherical bodies of optical quality includes filling receptacles (2) in a heat-resistant support (3) made of a porous material with glass gobs (1); conducting gas through the heat-resistant support so that a gas flow (4) passes through the support in a direction (14) opposite to a direction in which gravity acts; heating the heat-resistant support (3) to a temperature at which the glass gobs (1) have a viscosity of up to about 106 poise; maintaining the support (3) at this temperature for a predetermined time interval; and then cooling the support (3) to ambient temperature while continuing to provide the gas flow (4) through the support (3).