Novel technique for the determination of hydroxyl distributions in fused silica.
Bound OH- is one major unwanted absorbing impurity causing significant attenuation for certain wavelengths of laser radiation when propagating through fused silica. A wavelength tunable laser calorimeter (LCA) is used to detect dopants and other impurities in optical material. Also, a technique for photothermal absorption measurements is combined with the LCA set-up allowing for a lateral scan of the sample retaining an absolute calibration. Regarding inhomogeneities within the distribution of impurities the combination of both techniques provides a highly sensitive method to investigate in the lateral distribution of OH- content in fused silica.
Jensen
Lars O
LO
Laser Zentrum Hannover e.V., Department of Thin Film Technology, Hollerithallee 8, 30419 Hannover, Germany. l.jensen@lzh.de
Balasa
Istvan
I
Blaschke
Holger
H
Ristau
Detlev
D