A novel design of bireflective symmetric beam splitting prism and parallel beam splitting prism

In the technology of laser modulation, it is very difficult to produce bireflective symmetric beam splitting prism and parallel beam splitting prism with large shear difference because of technical and material restrictions. In order to improve the symmetry and parallelism of output beams of a polarization prism, two design schemes are presented from the perspective of the structure of bireflective prism. One scheme is to change angle parameters φ and β,which can not only ensure the symmetry of the splitting beam angle, but also broaden the splitting angle. Also, according to requirements, appropriate symmetric splitting angle can be obtained by choosing different angle parameters. Another scheme is to change one flat face of the exit facet into two convex faces,therefore,big shear difference can be obtained and the shear of the prism can be designed according to the customer's requirements. As a result, the application scope of the bireflective prism will be widened greatly. The calculated result is well in agreement with experiments.