讨论了斜入射对薄膜的光学特性的影响，提出了呈椭球旋转面的彩色冷反光镜膜层的均匀分布不同于平行平面薄膜的均匀分布，在同一圆周方向上的膜层分布应均匀等厚，而从镜底到到镜口的轴向方向膜层应逐渐加厚。计算结果表明，膜层逐渐加厚，可以使各部位反射光的中心波长相同，同时也满足各部位的高反射带带宽近似相等 The influence of oblique incidence on the optical properties of the film is discussed. The uniform distribution of the color cold mirror film with ellipsoidal rotating surface is different from that of the parallel plane film. The film distribution in the same circumferential direction should be uniform Thick, and from the mirror to the mirror to the axial direction of the film should be gradually thickening. The calculation results show that the thickening of the film gradually increases the central wavelength of the reflected light of each part and also meets the approximately equal bandwidth of the high reflection band of each part