Nonparaxial propagation of Gaussian beams on the angle to the axis of the anisotropic crystal

In this article propagation of laser beams in anisotropic crystals at an angle to a crystal axis also is analytically and numerically investigated. For an uniaxial crystal with use of a method of a stationary phase the analytical expressions showing dependence of astigmatic distortion from polarisation of the falling bunch are received. Also it is shown that a laser beam propagating at an angle to a crystal axis undergoes the birefringence effect which can disappear in accordance with of a plane of an inclination of a beam and a plane of linear polarisation. For Gaussian beams the expression connecting parametres of a beam and a crystal at which there is visual division of ordinary and extraordinary beams is received.