Scientech S200 Vector - Manual (Page 22)

front to back. Because the absorber (glass) is a poor conductor of heat, the same laser power density will
produce a much higher surface temperature than it would produce on the surface absorber. Furthermore, the
glass will confine the heat laterally while the surface absorber does not. The maximum power density for the
volume absorber is nearly one tenth that of the surface absorber.
If a repetitively pulsed laser is supplying a steady power input the situation is even more complicated.
Superimposed upon the average linear temperature drop is the pulse by pulse instantaneous temperature
rise. If we ask how these various parameters of the laser input can vary we obtain a family of curves for the
same glass absorber. (See Figures 5 and 6). For ACX2501 multiply the Power Density and the Energy
Density by 8.
Figure 5
Figure 6
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The variation of absorptance with wavelength is depicted in Figure 7. The parameter "a" is the depth of
penetration 1/e reduction in laser intensity.