However, in the limit of the spatial extent of the optical wave being much less than the width of the crystal, the dark soliton can affect the other one whereas the bright soliton cannot.

• 当入射光束的空间展宽尺寸远小于晶体尺寸时，孤子对中的暗孤子可以影响到另一个孤子，明孤子则不能。