Spatial light interference microscopy (SLIM)

Department of Electrical and Computer Engineering, Beckman Institute for Advanced Science & Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Optics Express (Impact Factor: 3.49). 01/2011; 19(2):1016-26. DOI: 10.1364/OE.19.001016
Source: PubMed


We present spatial light interference microscopy (SLIM) as a new optical microscopy technique, capable of measuring nanoscale structures and dynamics in live cells via interferometry. SLIM combines two classic ideas in light imaging: Zernike's phase contrast microscopy, which renders high contrast intensity images of transparent specimens, and Gabor's holography, where the phase information from the object is recorded. Thus, SLIM reveals the intrinsic contrast of cell structures and, in addition, renders quantitative optical path-length maps across the sample. The resulting topographic accuracy is comparable to that of atomic force microscopy, while the acquisition speed is 1,000 times higher. We illustrate the novel insight into cell dynamics via SLIM by experiments on primary cell cultures from the rat brain. SLIM is implemented as an add-on module to an existing phase contrast microscope, which may prove instrumental in impacting the light microscopy field at a large scale.

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    • "However, they present only off-axis reconstruction method in the results and the system's magnification is commanded principally for the physical dimensions. The flexibility of DHM offers the possibility of using it with another well established technique in order to develop a more robust measurement system [13] [14]. The Mirau Interferometer is normally used as an optical profiler when high magnifications are needed; this interferometer has some important features, such as spherical aberration compensation, easy difference optical path compensation, and insensitivity to external vibrations [15]. "
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    Full-text · Article · Mar 2013 · Optics and Lasers in Engineering
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