For a TbFeCo quadrilayer illuminated by laser beam, absorption of the laser
power within different layers was considered by analysizing the rate of ab
sorption of energy per unit volume. With the help of implicit method, the p
rofile of temperature of the multilayer was given and the diffusion of heat
was studied. The effect of laser power, laser duration and the convection
loss at the front surface upon the thermal characteristics of the multilaye
r was investigated. This thermal analysis procedure provided a good example
for the thermal investigation within other optical disk systems.