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Laser-Induced Damage in Optical Materials
value f, Pr(T
onset
= ϕ), for a sample of area A is determined by formulating the probabili-
ties of two events. Event 1 occurs when there are no sites on the optic that can damage at
uence levels below ϕ. Event 2 occurs when there is at least one site that fails at exactlyϕ.
Events 1 and 2 are independent events so the Pr(T
onset
= ϕ) can be written as
Pr Pr Pr ,TEvent More than zero fail at
onset
=
=
1 (7.37)
which becomes
Pr Pr Pr .TNosites fail belowMorethanzerofailat
onset
=
=
φφ φ (7.38)
e probability that there are exactly no sites that can fail at level ϕ = 0 is given using the
defect ...