MANUFACTURING METHOD OF DOPED QUARTZ GLASS

• Main Authors: STEFFEN ZWARG, MALTE SCHWERIN, TROMMER MARTIN
• Format: Patent
• Language: English; Japanese
• Published: 08.02.2016
• Subjects: CHEMISTRY; GLASS; MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES; METALLURGY; MINERAL OR SLAG WOOL

PROBLEM TO BE SOLVED: To provide a manufacturing method of doped quartz glass as an optical component.SOLUTION: A manufacturing method of doped quartz glass includes: a) a step of preparing a soot body having average density in the range of 18 to 30% to the specific gravity of quartz glass; b) a step of forming a fluorinated intermediate product (A) while processing the soot body by gas containing fluorine-containing compound in a process chamber, and increasing average density of the intermediate product (A) by up to 30% with respect to the average density of the soot body in step a); c) a step of forming a fluorinated intermediate product (B) while heating the fluorinated intermediate product (A) to temperature in the range of 950 to 1,150°C, and in which average density of the fluorinated intermediate product (B) is up to 80% with respect to the specific gravity of quartz glass, preferably up to 60%; and d) a step of vitrifying the fluorinated intermediate product (B) in the process chamber, and in which internal pressure of the process chamber is lower than external pressure of the process chamber while the doped quartz glass is being formed.SELECTED DRAWING: None 【課題】光学部品としてのドープ石英ガラスの製造方法の提供。【解決手段】ａ）石英ガラスの比重に対して１８〜３０％の範囲の平均密度を有するスート体を準備するステップ、ｂ）前記スート体を、プロセスチャンバーにてフッ素含有化合物を含むガスで処理しつつ、フッ素化中間産物（Ａ）を形成させ、中間産物（Ａ）の平均密度が、ステップａ）のスート体の平均密度に対して最大３０％増加するステップ、ｃ）フッ素化中間産物（Ａ）を９５０〜１，１５０℃の範囲の温度に加熱しつつ、フッ素化中間産物（Ｂ）を形成させ、フッ素化中間産物（Ｂ）の平均密度が、石英ガラスの比重の最大８０％、好ましくは最大６０％であるステップ、及びｄ）プロセスチャンバーにて前記フッ素化中間産物（Ｂ）をガラス化させ、前記ドープ石英ガラスを形成している間、前記プロセスチャンバーの内部圧力が、前記プロセスチャンバーの外部圧力よりも低いステップを含む。【選択図】なし