A surface casted thinly polymer (PVAC for experiment) on Au layer deposited on a PET film was overlaid to a reflection surface of a germanium prism at an incident angle of 22°. Absorbance of reflection spectra by P polarized radiatioa from these configuration was 2.5 times more than one of reflection-absorption spectra at an incident angle of 80°. Gains of absorbance by overlaying metal surfaces to the reflection surface of the germanium prism decreased at large incident angles, when coarse surfaces of metals were applied. It was due to an air layer between the metal surface and the reflection surface of the germanium prism, whose thickness exceed a penetration depth of the electromagnetic field from the refrection surface. Spectra of the PVAC film on the reflection surface of the prism by the S poralized radiation suggested how thick the air layer was in comparison with the penetration depth.
A TEA CO2 laser beam (500 mj, 100 ns) has been focused on metal samples under various pressures of surrounding gas. A luminous plasma with a hemispherical shape of about 3 cm radius is produced at the pressure of 1 Torr, while the gas breakdown takes place predominantly at pressures of above 10 Torr. The plasma has thin shell structure. The displacement of the front of the shell is proportional to the two-fifths power of time. The luminous plasma is found to be excited by the blast wave produced by the atoms gushed from the sample.