Sanchez-Brea Luis Miguel, Saez-Landete Jose, Alonso Jose, Bernabeu Eusebio
Department of Optics, Applied Optics Complutense Group, Facultad de Ciencias Físicas, Universidad Complutense de Madrid Ciudad Universitaria s.n., Madrid, Spain.
Appl Opt. 2008 Apr 1;47(10):1470-7. doi: 10.1364/ao.47.001470.
The Talbot effect is a well studied phenomenon by which grating pseudoimages appear at certain periodic distances when monochromatic light is used. Recently, numerical simulations have shown a new phenomenon; when a polychromatic light beam is used in a double grating system, the intensity of the pseudoimages presents a transverse-profile that remains unaffected over a wide range of propagation distances. This effect can be used to increase the tolerances of gratings based optical devices, such as displacement measurement systems, interferometers, and spectrometers. The pseudoimages formation with a polychromatic and finite extension light source is analytically and experimentally demonstrated. Relatively simple analytical expressions for the intensity and the contrast allow us to predict when pseudoimages present a constant contrast and when they disappear. Furthermore, we experimentally obtain the pseudoimages using the proposed configuration, corroborating the theoretical predictions.
塔尔博特效应是一种经过充分研究的现象，当使用单色光时，在特定的周期性距离处会出现光栅伪像。最近，数值模拟显示了一种新现象；当在双光栅系统中使用多色光束时，伪像的强度呈现出一种横向分布，在很宽的传播距离范围内保持不变。这种效应可用于提高基于光栅的光学器件（如位移测量系统、干涉仪和光谱仪）的容差。通过分析和实验证明了多色有限扩展光源下伪像的形成。强度和对比度的相对简单的解析表达式使我们能够预测伪像何时呈现恒定对比度以及何时消失。此外，我们使用所提出的配置通过实验获得了伪像，证实了理论预测。
