METHOD FOR PRODUCING A SIO2 BLANK

摘要

According to a known method for producing a SiO2 blank, SiO2 particles are formed in a plurality of deposition burners arranged in series, a burner flame being associated to each burner, and said particles are then deposited on a deposition surface of a carrier rotating about its longitudinal axis. The series of deposition burners moves back and forth according to a pre-determined displacement sequence along the blank being formed, and between inflection points at which the displacement direction is reversed. The burner flame forms a projection surface in a projection on a plane parallel to its main propagation direction, the lateral boundary lines of said projection surface forming an opening angle with the mean propagation direction. In order to provide a simple method for producing a porous blank, based on the above, and by which means a homogeneous quartz glass body is obtained, the opening angle ( alpha ) is set to a value of between 3 DEG and 15 DEG and the distance (D) between the deposition burner (2) and the deposition surface (10) is set between 170 mm and 240 mm.