分析了双平行平板的分光特性,并提出了优化其分光特性的方法。平行放置的平行平板可将入射光束同时分为多个峰值功率密度不同的光束出射,应用电荷耦合器件(CCD)相机接收出射光斑,出射光斑的峰值功率密度差异(DMPF)要保证小。分析了平行平板板间距和光束入射角对出射光斑的峰值功率密度差异的影响,结果表明,合理选取板间距和入射角可使光斑的峰值功率密度差异减小。当平板膜特性和入射激光中心波长确定时,最优板间距与光束的瑞利长度呈递增关系,最优入射角保持稳定,相应条件下的光斑峰值功率密度差异随瑞利长度的变化有轻微浮动。 The spectroscopic properties of double parallel plates are analyzed and a method of optimizing their spectroscopic properties is proposed. The parallel plates placed in parallel can split the incident beam into several beams with different peak power densities simultaneously. CCD cameras can receive the emergent spot, and the peak power density difference (DMPF) of the emergent spot should be kept small. The influence of parallel plate spacing and beam incident angle on the difference of peak power density of exit spot is analyzed. The results show that the difference of peak power density of spot can be reduced by reasonably selecting the plate spacing and incident angle. When the characteristics of the flat film and the incident laser center wavelength are determined, the optimum plate spacing is in increasing relation with the Rayleigh length of the beam, and the optimal incident angle remains stable. The difference of the peak power density with the change of Rayleigh length under the corresponding conditions is slight float.