Torcal-Milla Francisco Jose, Sanchez-Brea Luis Miguel, Salgado-Remacha Francisco Javier
Applied Optics Complutense Group, Optics Department, Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Ciudad Universitaria s.n., 28040 Madrid, Spain.
Appl Opt. 2009 Nov 10;48(32):6252-8. doi: 10.1364/AO.48.006252.
We analyze the near-field behavior of binary amplitude/phase diffraction gratings, which modulate at the same time the amplitude and phase of the incident light beam. As it is expected, the distance between two consecutive self-images of the grating depends only on the period of the grating and the wavelength of the illumination. However, the location of the self-images depends on the specific properties of the grating. In this work, we analyze the location of the self-images in terms of the Fourier coefficients of the grating, obtaining analytical expressions. This analysis can be useful in applications in which the position of the self-images must be at certain fixed distances from the grating. Finally, an experimental and numerical verification of the proposed theory is performed.
我们分析了二元振幅/相位衍射光栅的近场行为，该光栅同时调制入射光束的振幅和相位。正如预期的那样，光栅两个连续自成像之间的距离仅取决于光栅周期和照明波长。然而，自成像的位置取决于光栅的具体特性。在这项工作中，我们根据光栅的傅里叶系数分析自成像的位置，得到了解析表达式。这种分析在自成像位置必须与光栅保持特定固定距离的应用中可能会很有用。最后，对所提出的理论进行了实验和数值验证。
