The property of the laser beam through a light pipe is necessary to be considered when the light source changes to laser light. A simulation model is presented to investigate the property of a 532nm laser source after a 71-layer dielectric filmed hollow light pipe structure in ZEMAX software. The results of the simulation model are experimentally verified using a polarimeter. The experimental results show that the multilayer dielectric film light pipe can increase reflectivity and diversify the linearly polarized laser light to the different polarization shapes and orientations. The depolarization characteristics of the light pipe can be applied to modulate the degree of polarization of the laser light.