Hi MANG2004, ;nl JD#
#@nPB.
I am curious about your calculation, too. Plus, the definition of σ refers to 1/e^2 width not the FWHM. Even your calculation/defintion is correct. I have a doubt that it will work when the specualr incident ray angle is not normal......... A}! A*z<9
8K^#$,.."
For thsoe who knows it better, please have some input. I am rather curious, too!! Thanks!!