straw hat

The bumblebee sizzed right under his straw hat.

大黄他草底下丝丝作声。

The light intensity distribution exhibits straw hat shape on a certain conditions, in other word to say, the central light intensity is less than acroteric light intensity.

一定条件下，截面上光强布会呈现中心光强小于周围光强“草”布。