A double-logarithmic map with the five basic interaction types is shown in Fig. 3.1 as found in several experiments. The ordinate expresses the applied power density or irradiance in W/cm2. The abscissa represents the exposure time in seconds. Two diagonals show constant energy fluences at 1 J/cm2 and 1000 J/cm2, respectively. According to this chart, the time scale can be roughly divided into five sections: continuous wave or exposure times > 1 s for photo chemical interactions, 1min down to 1μs for thermal interactions, 1 μs down to 1ns for photo ablation, and < 1ns for plasma-induced ablation and photo disruption. The difference between the latter two is attributed to different energy densities. They will be addressed separately in Sects. 3.4 and 3.5, since one of them is solely based on ionization, whereas the other is an associated but primarily mechanical effect.

Bio-Medical Engineering-Lecture Notes