Sub-diffraction-limit

Rust, M. J., Bates, M. and Zhuang, X. (2006). Sub-diffraction-limit imaging by stochastic optical reconstruction microscopy (STORM). Nat. Methods 3, 793-5. 

Further developments are also expected in imaging applications with faster imaging methods with higher spatial resolution becoming available (e.g. sub-diffraction-limited spatial resolution). Advanced non-linear techniques such as CARS and specialist methods such as ROA will broaden their respective application areas, as instruments become more compact and more systems become commercially available. 

Z. Liu et al., Par-field optical hyperlens magnifying sub-diffraction-limited objects. Science 315(5819), 1686 (2007)... 

M.J. Rust, M. Bates, X. Zhuang, Sub-diffraction-limit imaging by stochastic optical reconstruction microscopy (STORM). Nat. Meth. 3, 793-796 (2006) S.T. Hess, T.P.K. Girirajan, M.D. Mason, Ultra-high resolution imaging by fluorescence photoactivation localization microscopy. Biophys. J. 91(11), 4258-4272 (2006)... 

Sub-Diffraction-Limit Imaging with Stochastic Optical Reconstruction Microscopy... 

To demonstrate that STORM can indeed resolve nearby fluorescent molecules with sub-diffraction-limit resolution, we first engineered samples with known relative positions of the fluorescent labels - double-stranded DNA labeled with two Cy3-Cy5 pairs separated by a well-defined number (135) of base pairs, corresponding to an inter-CyS distance of 46 nm along the contour of DNA [4]. The DNA strands were immobilized in a flat configuration to a quartz slide through multiple biotin-streptavidin linkages. The two Cy5 dyes were turned on and off, repetitively, and the image sequence was analyzed to determine the positions of individual activated Cy5 dye. We then constructed... 

We have captured clear images of sub-diffraction-limited features of nanoscale objects using a microsphere nanoscope in either transmission or reflection mode. For example, 30 nm thick chrome-film diffraction... 

Fig. 5 Microsphere nanoscope in reflection mode images a commercial Blu-ray DVD disk. The 100 pm-thick transparent protection layer of the disk was peeled off before using the microsphere (size 4.7 pm). The sub-diffraction-limited 100 nm lines (a SEM image) are resolved by the microsphere superlens (b ON image). In a second example, reflectionmode imaging of a star structure made on a DVD disk thin film (c SEM image) is clearly discerned (d ON image)—including the complex shape of the star and its 90 nm-diameter corners.

Two-photon polymerization offers a unique combination of advantages. First, no topological constraints are present in the fabrication of a 3D microstructure. Second, sub-diffraction-limited resolution can be attained by employing laser intensities just... 

Fig. 18 Light intensity analysis for understanding the achievement of sub-diffraction-limit spatial resolution. Focal plane light intensity (dashed line) and the square of light intensity (solid line) distribution are associated with single-photon and two-photon excitation, respectively. Their derivative distribution is also shown. The inset is the diffraction pattern at the focal plane...

Fig. 19 Photopolymerization quenching by oxygen molecules under two mechanisms triplet state quenching (T-quenching) and radical quenching (R-quenching). The latter is the major factor that works in the sub-diffraction-limit fabrication...

Fig. 20 Achievement of sub-diffraction-limit voxels, a SEM image of voxels formed under different exposure durations, and b an exposure time-dependent lateral spatial resolution. The right-lower inset represents the dependence in half-logarithm coordinates. For different curves, the laser pulse energies are 163 pj (filled squares), 137 pj (filled circles), 111 pJ (filled triangles) and 70 pJ (up-side-down filled triangles), respectively...

Fig. 21 Different view-angle SEM images of a micro-bull sculpture that was two-photon photopolymerized with sub-diffraction-limit accuracy. The 10-/im long and 7-/rm high bull is believed the smallest animal sculpture that was ever fabricated...

With the sub-diffraction-limit fabrication accuracy, it is possible to fabricate devices of nanoscale size or with nano-features. Figure 21 is the SEM image of a micro-bull sculpture, which consists of smooth and rough surfaces, curvatures and sharp horns. It is good proof of the feasibihty of creat-... 

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