Maurer Christian, Schwaighofer Andreas, Jesacher Alexander, Bernet Stefan, Ritsch-Marte Monika
Division for Biomedical Physics, Innsbruck Medical University, 6020 Innsbruck, Austria.
Appl Opt. 2008 Aug 1;47(22):3994-8. doi: 10.1364/ao.47.003994.
A method to remove undesired diffraction orders of computer-generated binary phase holograms is demonstrated. Normally, the reconstruction of binary Fourier holograms, made from just two phase levels, results in an undesired inverted image from the minus first diffraction order, which is superposed with the desired one. This can be avoided by reconstructing the hologram with a diffuse light field with a pseudorandom, but known, phase distribution, which is taken into account for the hologram computation. As a consequence, only the desired image is reconstructed, whereas all residual light is dispersed, propagating as a diffuse background wave. The method may be advantageous to employ ferroelectric spatial light modulators as holographic display devices, which can display only binary phase holograms, but which have the advantage of fast switching rates.
展示了一种去除计算机生成的二元相位全息图中不需要的衍射级次的方法。通常，由仅两个相位水平制成的二元傅里叶全息图的重建会导致来自负一级衍射级次的不需要的倒立图像，该图像与所需图像叠加。这可以通过用具有伪随机但已知相位分布的漫射光场重建全息图来避免，该相位分布在全息图计算中被考虑在内。结果，仅重建所需图像，而所有剩余光被散射，作为漫射背景波传播。该方法对于采用铁电空间光调制器作为全息显示装置可能是有利的，铁电空间光调制器只能显示二元相位全息图，但具有快速切换速率的优点。
