Patent ID: 7162894

Claim:
Method for loading a quartz glass object wit hydrogen in order to effect homogeneity of refractive index and increase laser resistance of said quartz glass object, and for maintaining a specified stress birefringence of said quartz glass object, said method comprising: determining values of a plurality of process parameters relating to a process for annealing said quartz glass object in an annealing furnace to hydrogen-load said quartz glass object, said process parameters comprising: change in hydrogen loading of said quartz glass object required to effect homogeneity of the refractive index of said quartz glass object, annealing furnace temperature at which said quartz glass object is to be hydrogen-loaded, annealing time of said quartz glass object in said annealing furnace, hydrogen concentration in said annealing furnace, and hydrogen pressure in said annealing furnace; and annealing said quartz glass object in said annealing furnace under values of said plurality of determined process parameters, which are adjusted during said annealing in order to maintain an appropriate overall set of conditions necessary for sufficiently homogenizing the distribution of the refractive index in the quartz glass object.