Patent ID: 8156761

Claim:
A method for producing quartz glass from powder using a Verneuil method, said method comprising: providing a mixed powder comprising quartz powder and two or more types of dope elements in an amount of from 0.1 to 20% by mass in total, wherein the dope elements comprise a first element selected from the group consisting of N, C and F, and a second element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, lanthanides and actinides by mixing said quartz powder with said dope elements so as to form said mixed powder; producing a quartz glass ingot by sequentially heating, fusing and dropping the mixed powder; and wherein, during said producing of the quartz glass ingot, the mixed powder is heated such that a surface temperature of the quartz glass ingot reaches 1800° C. or more; and wherein the quartz powder has a hydroxyl group content in a range from 50 to 200 wtppm.