INFLUENCE OF SELF-ABSORPTION OF 213 nm RADIATION ON LASER TREATMENT OF CORNEA
Abstract
The laser ablation efficiency of cornea at 213 nm radiation was investigated and optimized. It is shown that self-absorption of radiation at 213 nm in a thin cloud of ablated material takes place and strongly influences the ablation efficiency. Ablation products are being blown out in the lateral direction along the cornea surface, as a result of which the pulse fluence at the pit boundary Fbnd is more than the threshold fluence Fth. As a consequence, a pit radius rbnd is less than a laser beam radius rth corresponding to the threshold fluence Fth that should be taken into account in planning ablation surgery at 213 nm radiation.
About the Authors
S. A. Batishche
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk
Belarus
Belarus
S. V. Bushuk
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk
Belarus
Belarus
A. A. Kouzmouk
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk
Belarus
Belarus
A. V. Savitch
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk
Belarus
Belarus
H. A. Tatur
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk
Belarus
Belarus
G. Grabner
Paracelsus Medical University, University Eye Clinic, Salzburg
Austria
Austria
W. Kautek
University of Vienna, Department of Physical Chemistry, Vienna
Austria
Austria
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