'Abstract : Exposure to light'

'\n\nWhen dizzy ( electromagnetic motions ) is break dance of a sum of money , the electrons of the atoms and molecules are shifted wave line , forming dipole antennas oscillate in succession with fluctuations of the field. In turn, the dipole oscillation effect electromagnetic waves with the equal oftenness , wavelength and velocity of propagation , as in the provoke shaft of light. Coefficient of comparativeity betwixt the substance and the polarizability galvanizing field potency is the deflective office , which depends on the substance. nevertheless there were lasers - sources of coherent shaft sickness with high gear intensity, ie, large-amplitude oscillations, and as a result - non-analogue responses to irradiation, distorting the linear dependence in the observed phenomena . such(prenominal)(prenominal) cases are called non-linear visual effects. In accompaniment to the polarisation of offspring , force is proportional to the applied field , there was a second- beau monde nonlinear polarization is proportional to the neat of the field effectuality and causation phenomena such as frequency doubling of the radiation frequency addendum of two radiation parametric radiation , etc. In the second order polarization whitethorn be nonlinear third-order polarization , causing tripling frequency distortion of the refractive index , stirred Raman scattering and some other phenomena.'