At the back focal plane of the objective, the blue wavelengths from each slit interfere constructively to produce the blue area of the diffracted image of each spectrum or order; similarly for the red and green areas (Figure 4(a)).

• 在物镜的后焦面，从各个窄缝发出的蓝色波长光产生增强干涉而产生各级的衍射图像的蓝色区域，红色波长和绿色波长也一样(图4(a))。