Fluence equation
F=Foe-ad , F = fluence at depth d, Fo = fluence at surface, a = linear absorption coefficient
- for d = 0 (surface), F=Fo, the threshold fluence (Fth)
ln F = ln Fo + -ad, where ln Fo is the y-intercept and -a is the slope
Eth = Fth x a , energy threshold required for ablation