Microfabrication of diffractive optical element with continuous relief by focused ion beam
The diffractive optical element (DOES) with continuous relief and submicron feature size is very useful for optical fibre communication due to its perfect coupling. Microfabrication of the DOES by focused ion beam (FIB) technology is introduced in detail in this paper. Based on analyzing influencing factors such as ion dose, beam spot size, beam current and dwell time etc., controlling the process of continuous relief form is discussed. It is shown by testing results that the form of milled continuous relief is accurate enough for the application of fibre communication with its high diffraction efficiency.
continuous relief focused ion beam does