An attempt to solve the heat diffusion equation of the laser heating p
roblem is made by suggesting a solution which satisfies the physical a
nd mathematical requirements of the problem. This was done by consider
ing a constant laser irradiance for the cases of constant and temperat
ure-dependent optical absorbance of the slab front surface. For both c
ases, expressions for the temperature profile in the slab material, it
s front and rear surface temperatures, the thermal penetration depth a
nd the time required to initiate damage (melting) are obtained for int
ervals less or greater than the transit time. As an illustrative examp
le, computations are carried out on an Al-slab.