當電子束通過期光柵金屬結構時會激發Smith-Purcell輻射，而Smith-Purcell輻射可以經由很多外在條件而改變其輻射角度，而Smith-Purcell輻射與一般表面電漿不同，表面電漿只能存在於金屬表面上，Smith-Purcell輻射卻可以在空間中傳播，故我們將Smith-Purcell輻射應用在軍事用途、生物醫療等等領域 。
本研究論文使用模擬軟體Lumerical探討如何激發和調控Smith-Purcell輻射，透過改變電子束能量強度與光柵週期大小，能使輻射角度改變，再透過組合不同週期大小的光柵或將週期光柵更改為螺旋光柵結構，使Smith-Purcell輻射能有多個角度的輻射或者產生軌道角動量。

In this paper, a ring electron beam is used to excite the surface plasmon on the cylinder, and then the surface plasmon is converted into Smith-Purcell radiation by designing a periodic grating. By changing the period size and electron beam speed of the grating structure, Smith- Purcell radiation radiates out at the angle we want. Then change the periodic grating to a helical periodic grating, which can radiate the orbital angular momentum beam, and then radiate through Smith-Purcell to design the radiation at the angle we want.

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