In order to improve the near field uniformity of the "SG Ⅱ"laser beam, we haveproposed and designed a special beam,called flat-top centered dip beam.

Theory of surface thermal lens signal in optical coating with cw modulated top-hat beam excitation;

The spectral propagation equation of flat-topped beams propagating through atmospheric turbulence is derived by using the quadratic approximation of the Rytov s phase structure function.

The coherent combination of multi-Hermite-Gaussian beams is proposed to describe the flat-topped beams.

Propagation of flat-topped light beams passing through ABCD optical systems;

Making use of the new model of falt-topped light beams proposed by Li recently,the analytical expressions of the M~2-factor and the field distribution of flat-topped light beams passing through a paraxial ABCD optical system have been derived,respectively.

Gaining of hollow beam with high efficiency by LCD s phase modulation;

Each of hollow beams has its own particular physics character,this causes widely applied in the trapping particles,four-dimension manipulating,guiding cold atomic,and atomic funnel and so on.

In the paper,We put forward to a sort of hollow beam which is based on intracavity transformation.

At present,the propagation property of hollow laser beams in free space has thorough theoretical research,but the propagation property of hollow laser beams in atmosphere medium does not have material canvass yet.

Recently,the formation and application of the hollow laser beams have been more and more concerned along with the development of laser technology and the expand of its application area.