Experimental generation of tunable star-shape laser beam from Gaussian beam

Optical beam plays an important role in many optical systems, and beam construction has attracted much attention. In this paper, we proposed a new kind of tunable star-shape laser beam whose phase wavefront distribution is the sine function of azimuthal angle. And a simple method was also carried out to generate this kind of beam based on computer-generated holograms. Experimental results show that the transverse intensity pattern of the tunable star-shape laser beam changes very considerably on increasing beam parameter that contained in the sine function term of phase wavefront distribution. When beam parameter is smaller than 3, and the number of intensity peak equals beam parameter. When beam parameter is bigger than 4, transverse intensity pattern turns star shape, and its branch number equals beam parameter.