Steiger Ruth, Bernet Stefan, Ritsch-Marte Monika
Division for Biomedical Physics, Innsbruck Medical University, Müllerstr. 44, A-6020 Innsbruck, Austria.
Opt Express. 2012 Jul 2;20(14):15377-84. doi: 10.1364/OE.20.015377.
In various microscopy applications spatial light modulators (SLMs) are used as programmable Fourier filters to realize different optical contrast enhancement methods. It is often advantageous to use the SLM in off-axis configuration, where the filtered image wave is sent into the first diffraction order of a blazed grating superposed to the phase mask on the SLM. Because of dispersion this approach is, however, typically limited to spectrally narrowband illumination. Here we suggest a method involving a grating for pre-compensation, which allows one to use spectrally broadband (even thermal) light in SLM-based Fourier filtering. The proposed approach is demonstrated by multicolor imaging of amplitude and phase objects, such as a resolution target, onion epidermal cells and human epithelial cheek cells.
在各种显微镜应用中，空间光调制器（SLM）被用作可编程傅里叶滤波器，以实现不同的光学对比度增强方法。将SLM用于离轴配置通常具有优势，在这种配置中，滤波后的图像波被发送到与SLM上的相位掩模叠加的闪耀光栅的一级衍射级中。然而，由于色散，这种方法通常限于光谱窄带照明。在此，我们提出一种涉及用于预补偿的光栅的方法，该方法允许在基于SLM的傅里叶滤波中使用光谱宽带（甚至热）光。通过对振幅和相位物体（如分辨率靶标、洋葱表皮细胞和人类上皮颊细胞）进行多色成像，验证了所提出的方法。
