And when you shine a light through one of these gratings, the diffraction lines are much more intense and easier to measure.

当你通过其中一个光栅照射光线时，衍射线会更加强烈并且更容易测量。

So, if you know the distance between the slits, then you can measure the diffraction lines to get some information about the light source.

因此，如果您知道狭缝之间的距离，那么您可以测量衍射线以获取有关光源的一些信息。