The Rayleigh-Debye approximation in light scattering theory is extended to larger values of phase parameter. The first step in our theory is to assume that the amplitude of electric field of incident light inside the scatterer has spherical symmetry for spherical particles. The amplitude function is determined empirically from the analysis of scattering patterns computed from the Mie theory. The parameters of the function are particle size, relative refractive index of scatterer and wavelength of incident light. This function is incorporated in the original Rayleigh-Debye theory. From the numerical calculation of scattering patterns, the present approximation is verified to be valid in the range of phase parameter 2ka(nr-1)≤2π.
The properties of a solid thin film dye laser operating by radiative energy transfer have been studied experimentally. The laser devices with the active core and clad containing an acceptor dye and a donor dye, respectively, were prepared on a glass substrate. Under N2 laser pumping, efficient thin film dye laser operation occurred through radiative transfer for several donor-acceptor dye pairs without noticeable degadation. These thin film energy transfer dye lasers enable one to use them as compact laser sources.
The discontact ratio in sliding friction is markedly influenced by kinetic factors; mass distribution, elasticity, applied load, sliding velocity, etc. Friction, which is one of the factors, is known to be very much dependent on the surface characteristics of materials. For-this reason, the discontact ratio should be de-pendent to a marked degree on the character-istics of the sliding materials. To confirm the above supposition, the dis-contact ratio was measured under same sliding conditions for two different sets of materials. The results have shown that the sliding characteristic of materials has a marked in-fluence on discontact ratio. The better the sliding contact, the smaller the discontact ratio.