濾波繞射元件之設計與應用

Abstract

繞射光學元件擁有一般傳統光學元件所無法達到的功能，不僅輕、薄、小和可大量製作外，一些特殊的功能更是它目前會這麼受重視的原因。 本論文即利用想繞射光學元件的特殊色散效果去設計濾波繞射元件，以期能達到窄波段濾波和聚焦的功能。本設計是利用相位恢復演算法來模擬四個波長的光波（1533nm,1541nm,1549nm和1557nm）平行入射濾波繞射元件後，將其中一個波長聚焦在軸上，其他光波則色散到聚焦區之外，以便我們取用此光波。 其中我們會在第二章說明此演算法和模擬流程，第三章提出設計的結果，在稍後幾章做製程討論和結論。

The diffractive optical elements (DOEs) are characterized not only by their small weight, small size and easy mass-production, but also their some special functions, which are hardly provided by conventional optical elements. In this thesis, by using the dispersion effect of the DOEs, four filters at wavelength 1533, 1541, 1549and 1557nm have been designed that have both the narrow-band filtering and focusing functions. In this design, a retrieval phase algorithm is used .As a plane wave containing the above four wavelengths is incident upon one of the filters, only the wave corresponding to the selective wavelength is focused on a small circular area centered at the axis and the other waves are dispersed this area. The algorithm and simulation process are described in chapter two and the simulation results are presented in chapter three. In the following chapters the fabrication process and the experiment measurements are discussed.