Effect of polarization error on combining efficiency of coherent polarization beam

To further improve combining efficiency of polarized beam combination, effect of polarization error and systematical extensibility were analyzed byusing numerical simulation method. The influence of polarization error on combining efficiency of coherent polarization beams was calculated under three kinds of different expanded structures. The overall combining efficiency of 16 path beamswith Y structure decreases 0.33% when the transmittance of polarization beam combiner(PBC) and the reflectance of PBC are 96% and 99.5% respectively, the transmittance of the half wave-plate is 99.7% and polarization error is 0.03rad. The combining efficiency declines gradually with the increase of beam number.The combining efficiency of 128 beams with Y structure drops to 83%. The results show that, Y structure with the relative balance of light power has the highest combining efficiency, and has the least influence by the polarization error.This study determines the optimal combining scheme of the system and provides a reference for the efficiency analysis based on coherent polarization combination.