摘要 |
Provided is a burner for manufacturing a porous glass base material, the burner having: a glass raw material gas ejection port; a burnable gas ejection port provided around and centered on the glass raw material gas ejection port; and one or more sequences of small diameter auxiliary gas ejection ports provided inside the burnable gas ejection port, to be coaxial with respect to the glass raw material gas ejection port, where in each of the sequences, the small diameter auxiliary gas ejection ports have the same focal length as each other, and have a concave portion at an end surface thereof.
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